Magnetic Resonance Imaging Evaluation of Common Spinal Intramedullary Tumours: Ependymoma and Astrocytoma

This cross-sectional study was carried out in the Department of Radiology and Imaging, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh, from January 2015 to June 2016 in collaboration with Department of Neurosurgery and Department of Pathology of same hospital, to assess MRI findings of common IMSCTs and to find out the validity of MRI in the diagnosis of spinal ependymoma and astrocytoma, thereby differentiating these two common intramedullary entities. For this purpose, 40 patients aged from 15 to 60 years, who were diagnosed or suspected cases of having intramedullary spinal cord tumours were enrolled. These patients underwent preoperative MRI for evaluation of the spinal cord tumours during the study period in department of Radiology and Imaging. Also, patients were diagnosed by MRI as having IMSCTs incidentally was included. All of them were followed by histopathological examination of the same lesions after surgery. Among these 40 patients after exclusion for valid reason 28 cases were included as study population. MR images were obtained on a 1.5 Tesla (Avanto Magnatom, Siemens) unit with a spine surface coil. MRI findings were compared with histopathology after surgery keeping histopathology as gold standard. Out of 28 clinically and MRI diagnosed IMSCTs cases, 19 cases of ependymoma, 8 cases of astrocytoma and one diagnosed as hemangioblastoma by MRI. The mean age was 34.11±9.55 years, ranging from 15 to 56 years for ependymoma, 26.88±8.08 years ranging from 16 to 44 years for astrocytoma. Highest incidence (47.4%) was in between 31 to 40 years for ependymoma, 50.0% were in between 21-30 for Astrocytoma. On MRI majority 12(63.2%) of the cord ependymomas and majority 5(62.5%) of astrocytomas were in cervical region. While considering axial location ependymomas are mostly 17(89.5%) central and astrocytomas 5(62.5%) are eccentric in location. It was observed that out of 19 cases of ependymoma more than half 10(52.6%) had elongated shape, 12(63.1%) had well defined margin. Associated syringohydromyelia was present in 16(84.2%) cases. On T1WI 11(57.9%) and 8(42.1%) cases were iso and hypo respectively. On T2WI 14(73.7%) cases were hyper intense. After Gd-DTPA in most cases, 13(68.4%) cases showed diffuse enhancement. Noticeable and sizeable solid component observed among 13(68.4%) of the cases. Hemorrhage with cap sign was found in more than one third 7(36.8%) cases. Out of 8 cases of astrocytomas 4(50.0%) had lobulated shape, ill-defined margin 5(62.5%). T1WI: Iso 5(62.5%), hypo 3(37.5%), T2WI: hyper 5(62.5%), After Gd-DTPA: focal and heterogenous enhancement 3(37.5%) and rim enhancement 4(50.0%). Component: mixed 4(50.0%), cystic 3(37.5%) and solid 1(12.5%). Hemorrhage without cap sign 2(25.0%), associated syringohydromyelia 1(12.5%). In the case of evaluation of intramedullary ependymoma sensitivity of MRI in the present series is 94.44%, specificity 80.0%, Positive predictive value (PPV) 89.5%, Negative predictive value (NPV) 88.9% and accuracy 89.28%. In case of MRI evaluation of intramedullary astrocytoma sensitivity of MRI in the present study is 85.71%, specificity 90.47%, PPV 75%, NPV 95% and accuracy 89.2%. Thus present study shows MRI is a sensitive and effective noninvasive imaging modality in diagnosing common intramedullary spinal cord tumours.

First account of microplastics in pelagic sporting dolphinfish from the eastern Mexican coast of Baja California Sur

This study is a baseline data on the presence of MPs from the gastro-intestinal tracts (GITs) in Coryphaena hippurus Linnaeus, from eastern Baja California Sur, México. 878 MPs items (in %) of fibers (29%), fragments (68%) and films (1.3%) were detected from 51 GITs of Coryphaena hippurus. Transparent, white, blue and black were the prevalent colours. Morphological features observed through SEM analysis, the presence of heavily weathered MPs is due to the mechanical, microbiological and chemical weathering process. PP (29%), Nylon (29%), PS (17%), PE (11%), PET (6%) and HDPE (8%) presence indicates their source from regional anthropogenic stress. Trophic level transition is enforced by polymer derivative, permitting the sinking behavior of MPs and increased ingestion probability. Fishes were classified as slim despite their higher feeding capabilities and ingested MPs indicates a relationship with environmental contaminants. Current study emphasizes the health risk linked to biological aspects of MPs ingestion.

Identification of suitable zones and sites for rainwater harvesting using GIS and multicriteria decision analysis

Identifying suitable zones for surface water storage and groundwater recharge is needed to enhance irrigation water availability. This study was undertaken to map rainwater harvesting (RWH) potential zones using geospatial tools and analytic hierarchy process (AHP). The suitable locations for RWH were also mapped using the Boolean logic concept. The surface runoff is a vital factor to demarcate the appropriate zones for RWH. The curve number approach was used to estimate the surface runoff potential. The runoff coefficient (RC) map was generated based on rainfall and surface runoff depth. Weights have been allocated to selected themes of RC, drainage density, and slope. The themes were integrated using geographic information system (GIS) and AHP to demarcate the suitable zones for RWH. The derived RWH potential map was categorized into zones like "very good," "good," "moderate," "poor," and "very poor" with an aerial extent of 14.3%, 24.7%, 28.3%, 20.2%, and 12.6%, respectively. The area suitable for farm ponds was found to be about 9% (408 km²), 13% (329 km²), and 4% (244 km²) in Mirzapur, Chandauli, and Sonbhadra districts, respectively. Furthermore, 22, 15, and 21 locations were found suitable for check dams in Mirzapur, Chandauli, and Sonbhadra districts, respectively. At a large scale, effective planning of water management strategies based on multicriteria decision analysis and GIS offers increased availability of surface and groundwater resources and may help for enhancing the agricultural land use options. The higher resolution maps may be further utilized to plan RWH strategies at village level.

Diagnostic Accuracy of Magnetic Resonance Imaging in Evaluation of Anterior Cruciate Ligament Tear

The anterior cruciate ligament (ACL) is the most generally injured one of the major knee ligaments. These injuries plague both athletes and non-athletes. This cross-sectional and comprehensive study was conducted in the Department of Radiology and Imaging collaborating with Department of Orthopedics of Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh, completed from January 2014 to December 2015. The study evaluated the role of MRI in the diagnosis of anterior cruciate ligament injury of knee joint, keeping Arthroscopy as standard, compared the MRI and arthroscopic findings to determine accuracy, sensitivity and predictivity of MRI in the diagnosis of ACL injury in knee joint. For this purpose, a total of 50 patients having clinical suspicion of ACL injury in knee joint were enrolled in this study to perform MRI and Arthroscopy. MRI was done in all these patients. Clinically suspected but MRI diagnosed as no ACL injury, patients who were not willing to undergo arthroscopy examination and patient who were not fit for arthroscopy were excluded from the study. More than half (52.0%) of the patients were in 3rd decade and male to female ratio was 3.5:1. Less than one fourth (24.0%) of the patients were service holder. Forty two percent patients had duration of suffering for 2 weeks. Most 49(98.2%) patients had history of trauma, 45(90.0%) had pain in Knee joint, 24(48.0%) had difficulty in walking, 19(38.0%) had swelling in Knee joint and 13(26.0%) had restricted range of motion. Anterior drawer test was 37(74.0%) and Lachman test 16(32.0%). Loss of normal contour of ACL was found in 50.0%. Signal change of ACL in PD and T2W1 was found 42(84.0%) patients, and thickened ACL in 33(66.0%) patients. In MRI diagnosis tear was present in 80.0% of the patients. ACL tear diagnosed by MRI among the patients, 20(40.0%) had partial tear and 20(40.0%) had complete tear. In arthroscopy diagnosis 38(76.0%) had tear present. ACL tear diagnosed by arthroscopy of the patients 15(30.0%) had partial tear and 23(46.0%) had complete tear. Majority 20(40.0%) patients had medial meniscus injury, 15(30.0%) had lateral meniscus injury, 11(22.0%) had PCL injury, 4(8.0%) had lateral co-lateral ligament injury and 2(4.0%) had medial co-lateral ligament injury. In MRI diagnosis of anterior cruciate ligament tear, 37 cases were true positive, three cases false positive, one case false negative and nine cases was true negative. The validity of MRI diagnosis evaluation for anterior cruciate ligament tear was 97.4% sensitivity, 75.0% specificity, 92.0% accuracy, 92.5% positive predictive values and 90.0% negative predictive values.

Measurement of Bone Mineral Density in the Transfusion Dependent Thalassemic Patients

Low bone mineral density represents as a major cause of morbidity in thalassemic patient. The mechanism depends upon several factors. Transfusion dependent iron over load cause decrease secretion of growth hormone, insulin, thyroid hormone, parathyroid hormone, sex hormone and vitamin D from different endocrine organs which ultimately causes impairment of adequate bone mass achievement. Other causes of low bone mass are iron chelating agent and bony expansion due to increase erythropoiesis. To find out the frequency of low bone mineral density in thalassemia patients who are transfusion dependent. This study was designed as a cross sectional observational study, which was analyzed in the Department of Haematology, Bangabandhu Sheikh Mujib Medical University, Dhaka and National Institution of Nuclear Medicine and Allied Sciences (NINMAS), Bangladesh Atomic Energy Commission (BAEC) from September 2017 to August 2018. It had been performed over total 72 (Age ≥06 years to ≤40 years) thalassaemic patients who are transfusion dependent. Presence of bone diseases was detected by Bone mineral density (BMD). Seventy-two (72) patients with transfusion dependent thalassaemia, aged 6 to 39 years were enrolled. Mean age of patients was 20.9±7.2 years. Among them, 57(79.2%) patients were detected as a normal bone mineral density and fifteen (20.8%) patients were detected as a low bone mineral density in the left femoral neck. In transfusion dependent thalassaemic patient, Low bone mass was significantly associated with low BMI, total number of blood transfusion and serum ferritin level remarkably. This survey has established a new path for early detection of low bone mass and helped in prevention of bone loss and its sequel by starting early treatment in these groups of patients.

Occurrence, distribution and provenance of micro plastics: A large scale quantitative analysis of beach sediments from southeastern coast of South Africa

Microplastics (MPs) existence, identification and source were investigated by studying a total of 2539 particles in 349 sediment samples from nine different tourist beaches [(Sodwana & Richard Bays; Ballito, Mtunzini, Tugela, Zinkwazi, Ballito (north & south) and Durban north & south)] of southeastern coast of South Africa. They are more abundant in the beaches of the Durban city, followed by the Sodwana & Richards Bays, Ballito and Mtunzini. The black particles prevailed over the blue, white, pink, brown, red and green MPs. Supremacy of MPs in the Durban city is mainly due to the longshore coastal Agulhas current in the South eastern side of African coast aiding the degradation of primary plastics coming both from continent and sea. SEM images provided the evidences of weathering/degrading process through grooves, cracks, deep fissures, sharp edges and layered degradation showing signs of oxidation due to long term exposure in the coastal environment. EDS results suggested presence of elements (i.e. C, -O, Si, Al, Fe, Ca, Mg, Na, K, S, Ti, Cu and Zn introduced during the production of plastics as additives. FTIR spectral matches identified from all samples infer polypropylene (PP) (62%), rayon (RY) (17.2%), polycarbonate (PC) (29.8%), nylon (NY) (18.92%), polyester (PES) (31.2%), polyacrylonitrile (PAN) (11.21%) and polystyrene (PS) as well as low (28.9%) & high (36.1%) polyethylene terephthalate (PET). Higher abundance of MPs in the beaches of South Africa in comparison with studies around the world emphasizes the need of dispersal monitoring and use of plastic materials/polymers.

Elemental composition of aquaculture fish from West Bengal, India: nutrition versus food safety

Aquaculture production continues to grow in West Bengal, where on average people consume 8.2 kg capita^-1 of fish each year, and an extensive mosaic of aquaculture ponds has developed along the River Hugli as clay pits are repurposed. The adjacent brickworks and industry (especially tanneries) are a source of environmental pollution, with potential for bioaccumulation of potentially harmful elements (PHEs) in fish farmed in these ponds. Fish from aquaculture present an opportunity to meet food sufficiency in West Bengal; however, an investigation to assess their effectiveness for micronutrient supply balanced against food safety is required. Five ponds close to industrial brick manufacture (urban) and three from rural areas were assessed for the degree of pollution within their pond sediments and waters. Fish were also sampled from each location including a subset from the market in Kolkata to determine the concentrations of PHEs in their fish muscle tissue. Dietary intake and PHE loading were calculated for four fish species to evaluate their nutrient content with respect to recommended daily intakes for adults, e.g. calcium (Ca), potassium (K), magnesium (Mg), iron (Fe), zinc (Zn) and selenium (Se), and to establish whether the provisional maximum tolerable intakes (PMTIs) are exceeded for PHEs, e.g. aluminium (Al), arsenic (As), mercury (Hg), chromium (Cr), tin (Sn), copper (Cu) and lead (Pb). Preliminary results suggest that aquaculture is making an important contribution to nutrition, with fish being a good source of Se. However, in contrast to small wild-caught fish, aquaculture fish in the present study were poor sources of Fe, Ca and Zn. The fish also made substantial contributions (> 10%) to the PMTI of Hg and As. Therefore, there is an urgent need for ongoing monitoring and an expanded sampling programme, as well as research into approaches which might improve the nutritional quality of the farmed fish.

Adaptive co-management model for the East Kolkata wetlands: A sustainable solution to manage the rapid ecological transformation of a peri-urban landscape

Human-induced land use changes like agriculture and urban development occur commonly at the cost of natural wetlands, which require immediate attention and sustained efforts from urban planners and concerned governments. In view of the East Kolkata Wetlands (EKW), India, this paper has examined the trend, causes, extent and impacts of landscape transformation during the last few decades. Hence we aim to present a review of several studies in and around EKW and suggests a sustainable model for EKW. This 'Ramsar site of International Importance' is one of the world's largest wastewater-fed aquaculture systems where the city sewage is recycled for pisciculture and agriculture, and acts as flood resistance for the city of Kolkata. Rapid encroachment in the EKW due to unplanned development has caused various environmental, social and economic impacts. The key ecological impacts found in the study included loss of faunal and floral diversity, eco-toxicological impacts, etc. In terms of biodiversity loss, while the number of bird species in the EKW decreased from 248 in 1960s to 72 in 2005, about 59% fish species are near threats, vulnerable and endangered. Reported persistent organic pollutants (POPs) around the EKW region were found to pose deleterious impact on environment and ambient biota. Several studies have evidenced that the open burning of solid waste in the dumping ground of Dhapa is a potential source of polychlorinated biphenyls (PCBs) and polychlorinated dibenzo dioxin/furans (PCDD/Fs). Further the ecological transformation of the EKW focussing on policy development and regulatory compliance issues has been studied in this paper. The aspects of encroachment and wetland shrinkage triggered by economic drivers like urban sprawl have been analyzed. The paper presents adaptive co-management as the future roadmap for action to curb further degradation of the wetlands, and adopt an integrated approach of environmental, political, physical, economic and institutional aspects. It is envisaged that the adaptive co-management model will contribute to long-term sustainable sustenance of this precious ecosystem.

Comprehensive study on metal contents and their ecological risks in beach sediments of KwaZulu-Natal province, South Africa

Sediment metal concentrations were assessed in five different beach regions (n = 183) of KwaZulu-Natal (KZN) province in South Africa. Metal distribution revealed that Cr, Cu, Mo, Cd, Zn, Hg and As exceed the background upper continental crust values suggesting their anthropogenic origin (mining, agricultural and industrial) apart from natural geological inputs (gold placer deposits and heavy minerals). Various geochemical indices (Geoaccumulation index, Enrichment factor and Degree of contamination) confirmed that the sediment samples are extremely contaminated with Cr, Cd and Hg. Further, Hg and Cd were main contributors (60-90%) to the ecological threat in sediments. Hazard index estimated a high hazard potential of Hg in near future. Finally, present study together with our previous results portray the status of KZN coast with special significance to Hg contamination/enrichment. Thus, future researches are recommended to investigate the environmental and human health implications of mercury exposure in this coastal province.

Impact of conventional retting of jute (Corchorus spp.) on the environmental quality of water: a case study

Production of quality jute fibre primarily depends on the retting process of jute. However, the quality of retting water is of great concern because of the scarcity of available water bodies for retting. A study conducted on physico-chemical and microbiological changes in retting water (pre- and post-retting) from four intensively jute-growing districts namely Nadia, North 24 Parganas, Hooghly and South Dinajpur of West Bengal, India, during jute retting. The post-retting water samples recorded lower pH (6.22 to 7.08) and higher EC (electrical conductivity) (0.509 to 0.850 ds/m) compared with pre-retting water samples (pH 6.63 to 7.44; EC 0.197 to 0.330 ds/m) collected from all the four districts under study. The biological oxygen demand (BOD) and chemical oxygen demand (COD) increased several folds in the post-retting water samples indicating very high microbial growth and activities and depleted oxygen level compared with pre-retting water. The Ca + Mg (calcium + magnesium) content in pre-retting water was high (24.15 to 36.60 ppm) which raised further (61.30 to 103.67 ppm) in post-retting water, while the bicarbonate content also increased and ranged between 2.72 and 6.81 me/l in post-retting water compared with its status in pre-retting water (1.30 to 3.15 me/l). The post-retting water was found to be a rich source of nutrients like nitrogen (N), phosphorus (P), iron (Fe), manganese (Mn), zinc (Zn) and copper (Cu) which increased substantially because of jute retting as compared with their status in pre-retting water. The population of pectinolytic, xylanolytic, cellulolytic and ligninolytic bacterial cfu (colony forming unit) increased by 1.5 times in post-retting water as compared with pre-retting water, because these specific bacterial population were involved in the degradation of pectin, xylan, cellulose and lignin during retting of jute. Thus, post-retting water can be judiciously used as a potent source of primary, secondary and micronutrients for succeeding crops besides having higher BOD and COD as a result of higher microbial growth related to jute retting.

Red Cell Alloantibodies in Thalassaemia Patients Who Received Ten or More Units of Transfusion

Thalassaemia patients are the highest consumers of blood. Recurrent exposure to allogenic red cell antigen puts this population at increased risk of alloimmunization. This causes delayed hemolytic transfusion reactions. So transfusion requirement increases. But no data regarding alloimmunization was available in Bangladesh. Aim of this study was to estimate the prevalence of alloimmunization and to find out the potential factors associated with its development. This analytical cross sectional study was done by enrolling 97 patients, received at least 10 units transfusions, through convenient sampling. Indirect and direct antiglobulin tests were done to detect immunization by spin tube technique keeping an autocontrol and carried out in the Department of Haematology & Department of Transfusion Medicine, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh from March 2016 to March 2017. Polyclonal anti-AHG reagent was used. A total 21 patients developed alloimmunization (21.6%) and 4 patients (4.1%) developed autoimmunization. Age, gender, splenectomy and number of transfusion are shown significant risk factors for alloimmunization. Data from this study demonstrate that the RBC alloimmunization is significantly high in our country. So, pretransfusion antibody screening needs to be initiated in order to ensure safe transfusion and RBC phenotyping should be started before starting first transfusion to prevent alloimmunization.

In vivo cell-mediated immune, hemagglutination inhibition response, hematological and biochemical values in native vs. exotic chicken breeds

Birds (364) of both sexes, 11-wk-old, belonging to 2 native (Brown Nicobari and Ghagus) breeds and 1 exotic breed (Dahlem Red) were evaluated for cell-mediated immune response (CMI) by phytohemagglutinin-P (PHA-P), hemagglutination inhibition (HI) assay against Newcastle disease virus (NDV) antigen (LaSota stock virus), flow cytometric analysis of CD8+ cytotoxic T lymphocytes (CTLs), and hematology and biochemical assays. The cutaneous basophil hypersensitivity response PHA-P% increase in wattle thickness (mm) was highest in Ghagus (431.14 ± 22.56) which differed significantly with that of Brown Nicobari (269.1 ± 22.66) and Dahlem Red (218.42 ± 22.30). Sex-wise observation showed that females are having significantly higher response than males. Hemagglutination inhibition test was performed to determine the serum antibodies against Newcastle disease (ND) virus. Brown Nicobari showed highest HI antibody titer than Ghagus and Dahlem Red to similar vaccination program after booster NDV dose. Flow cytometry assay revealed significantly higher CTLs proliferation in Brown Nicobari than Ghagus and Dahlem Red. Moreover, CTLs were found to be higher in control group than the treatment group. Other hematological parameters (103/μL) significant difference was found in white blood cell count between Dahlem Red (38.41 ± 1.03) with that of Brown Nicobari (35.28 ± 1.04) and Ghagus (34.57 ± 1.04) in treatment groups. Same trend was observed in the Lymphocyte treatment group. However, in Granulocyte treatment group, Brown Nicobari (11.04 ± 0.35) was found to be significantly different from Dahlem Red (8.68 ± 0.34) and Ghagus (9.27 ± 0.35). Correlations between body weight at 11 wk of age and CMI, HI, cytotoxic T cell were -0.093, 0.047, and -0.036, respectively. Egg weight was found to be positively correlated with that of chick weight. Serum biochemical values showed that Dahlem Red was having significantly higher creatinine levels compared to Ghagus. Triglycerides level was also significantly higher in Ghagus compared to Dahlem Red. No significant breed effect was observed for alkaline phosphate, aspartate transaminase, and alanine transaminase. Cholesterol and total serum protein levels were significantly higher in Dahlem Red compared to Brown Nicobari.

Mercury levels in human population from a mining district in Western Colombia

A biomonitoring study was carried out to examine the adverse impacts of total mercury in the blood (HgB), urine (HgU) and human scalp hair (HgH) on the residents of a mining district in Colombia. Representative biological samples (scalp hair, urine and blood) were collected from volunteered participants (n=63) to estimate the exposure levels of THg using a Direct mercury analyzer. The geometric mean of THg concentrations in the hair, urine and blood of males were 15.98μg/g, 23.89μg/L and 11.29μg/L respectively, whereas the females presented values of 8.55μg/g, 5.37μg/L and 8.80μg/L. Chronic urinary Hg (HgU) levels observed in male workers (32.53μg/L) are attributed to their long termed exposures to inorganic and metallic mercury from gold panning activities. On an average, the levels of THg are increasing from blood (10.05μg/L) to hair (12.27μg/g) to urine (14.63μg/L). Significant positive correlation was found between hair and blood urinary levels in both male and female individuals. Thus the present biomonitoring investigation to evaluate the Hg levels and associated health issues would positively form a framework for further developmental plans and policies in building an ecofriendly ecosystem.

Spectroscopic identification of individual fluorophores using photoluminescence excitation spectra

The identity of a fluorophore can be ambiguous if other fluorophores or nonspecific fluorescent impurities have overlapping emission spectra. The presence of overlapping spectra makes it difficult to differentiate fluorescent species using discrete detection channels and unmixing of spectra. The unique absorption and emission signatures of fluorophores provide an opportunity for spectroscopic identification. However, absorption spectroscopy may be affected by scattering, whereas fluorescence emission spectroscopy suffers from signal loss by gratings or other dispersive optics. Photoluminescence excitation spectra, where excitation is varied and emission is detected at a fixed wavelength, allows hyperspectral imaging with a single emission filter for high signal-to-background ratio without any moving optics on the emission side. We report a high throughput method for measuring the photoluminescence excitation spectra of individual fluorophores using a tunable supercontinuum laser and prism-type total internal reflection fluorescence microscope. We used the system to measure and sort the photoluminescence excitation spectra of individual Alexa dyes, fluorescent nanodiamonds (FNDs), and fluorescent polystyrene beads. We used a Gaussian mixture model with maximum likelihood estimation to objectively separate the spectra. Finally, we spectroscopically identified different species of fluorescent nanodiamonds with overlapping spectra and characterized the heterogeneity of fluorescent nanodiamonds of varying size.

High resolution melting curve analysis targeting the HBB gene mutational hot-spot offers a reliable screening approach for all common as well as most of the rare beta-globin gene mutations in Bangladesh

BACKGROUND

Bangladesh lies in the global thalassemia belt, which has a defined mutational hot-spot in the beta-globin gene. The high carrier frequencies of beta-thalassemia trait and hemoglobin E-trait in Bangladesh necessitate a reliable DNA-based carrier screening approach that could supplement the use of hematological and electrophoretic indices to overcome the barriers of carrier screening. With this view in mind, the study aimed to establish a high resolution melting (HRM) curve-based rapid and reliable mutation screening method targeting the mutational hot-spot of South Asian and Southeast Asian countries that encompasses exon-1 (c.1 - c.92), intron-1 (c.92 + 1 - c.92 + 130) and a portion of exon-2 (c.93 - c.217) of the HBB gene which harbors more than 95% of mutant alleles responsible for beta-thalassemia in Bangladesh.

RESULTS

Our HRM approach could successfully differentiate ten beta-globin gene mutations, namely c.79G > A, c.92 + 5G > C, c.126_129delCTTT, c.27_28insG, c.46delT, c.47G > A, c.92G > C, c.92 + 130G > C, c.126delC and c.135delC in heterozygous states from the wild type alleles, implying the significance of the approach for carrier screening as the first three of these mutations account for ~85% of total mutant alleles in Bangladesh. Moreover, different combinations of compound heterozygous mutations were found to generate melt curves that were distinct from the wild type alleles and from one another. Based on the findings, sixteen reference samples were run in parallel to 41 unknown specimens to perform direct genotyping of the beta-thalassemia specimens using HRM. The HRM-based genotyping of the unknown specimens showed 100% consistency with the sequencing result.

CONCLUSIONS

Targeting the mutational hot-spot, the HRM approach could be successfully applied for screening of beta-thalassemia carriers in Bangladesh as well as in other countries of South Asia and Southeast Asia. The approach could be a useful supplement of hematological and electrophortic indices in order to avoid false positive and false negative results.

Impingement of marine organisms in a tropical atomic power plant cooling water system

A one-year impingement monitoring was conducted at Madras Atomic Power Station (MAPS), Kalpakkam, southeastern coast of India and identified a total of 67 species of marine organisms in the cooling water system. Estimates of total annual impingement contributed about 1.47×10⁶ individuals and 142.5t of biomass. Jellyfish contributed about 6.8×10⁵ individuals and 135.6t of biomass. Crabs, shrimps and fish were the most vulnerable organisms contributing about 4.29×10⁵ individuals, 1.39×10⁵ individuals and 2.16×10⁵ individuals respectively. Commercially important species namely Trichiurus lepturus, Sardinella longiceps and Portunus pelagicus were found to be impinged 1.88% and 0.29% by number and weight of the total biomass respectively. Out of ~327 fish species recorded at Kalpakkam, only about 9.4% of species were impinged at MAPS. Multispecies impingement at MAPS poses the problem of finding the best mitigation options for tropical conditions.

Detection of Ovarian Tumor by Color Doppler Ultrasonography and CA-125

Ovarian cancer is the most frequent cause of death from all gynaecological malignancies because of its insidious onset, vague symptoms and late presentation. This cross-sectional study was carried out on purposively selected 43 patients with suspected ovarian tumor in the Department of Radiology and Imaging in collaboration with the Department of Gynaecology and Obstetrics and Department of Pathology, Mymensingh Medical College Hospital, Bangladesh from January 2015 to December 2016 to assess the diagnostic performance of color Doppler ultrasonography and CA-125 in a combination described as Novel Index in detection of ovarian tumor. Highest number of patients of ovarian tumor 10(23.26%) were in age group 35 to 44 years and 45 to 54 years with a mean of 37.72±15.65 years with a range of 8-70 years. Histopathology findings revealed 19(44.18%) benign tumors and 24(55.82%) malignant tumors. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of Resistance Index (RI) in diagnosis of ovarian tumor were 91.67%, 89.47%, 91.67%, 89.47% and 90.69% respectively. Sensitivity, specificity, PPV, NPV and accuracy of serum CA-125 were 83.33%, 89.47%, 90.90%, 80.95% and 86.04% respectively. Sensitivity, specificity, PPV, NPV and accuracy of Novel index were 95.83%, 89.47%, 92.00%, 94.44% and 93.02% respectively. Novel index showed better diagnostic performance. Based on the current study it is concluded that the combination of color Doppler ultrasonography and serum CA-125 can be useful for diagnosis of ovarian tumor.

Estimation of microscope drift using fluorescent nanodiamonds as fiducial markers

Fiducial markers are used to correct the microscope drift and should be photostable, be usable at multiple wavelengths and be compatible for multimodal imaging. Fiducial markers such as beads, gold nanoparticles, microfabricated patterns and organic fluorophores lack one or more of these criteria. Moreover, the localization accuracy and drift correction can be degraded by other fluorophores, instrument noise and artefacts due to image processing and tracking algorithms. Estimating mechanical drift by assuming Gaussian distributed noise is not suitable under these circumstances. Here we present a method that uses fluorescent nanodiamonds as fiducial markers and uses an improved maximum likelihood algorithm to estimate the drift with both accuracy and precision within the range 1.55-5.75 nm.

Source, distribution and ecotoxicological assessment of multielements in superficial sediments of a tropical turbid estuarine environment: A multivariate approach

The work examined the distribution, possible sources and ecotoxicological assessment of 51 trace elements covering 13 sampling stations in surface sediments of coastal regions of Sundarban mangrove wetland and adjacent Hugli river estuary. The element concentrations exhibited an increasing trend towards downstream of the estuary (except lanthanides) with maximum enrichment for 22 elements at Gangadharpur (Sundarban region). According to Sediment Quality Guidelines (SQGs), the concentrations of Cu, As, Cr and Cd exceeded the Effects-Range-Low values, while Ni at certain stations exceeded the Effects-Range-Medium suggesting adverse effects on the sediment-dwelling organisms. The geoaccumulation index revealed that the stations were unpolluted to moderately polluted. Risk Index (357.61) and Enrichment factor (11.42) depicted that Nimtala station (upstream) was at high ecological risk zone. The result of PCA endorsed that organic carbon and clay fraction play crucial role in accumulating the elements in sediments. This pilot study contributes to a better understanding of the geochemistry of this complex deltaic ecosystem.

Modification of Monolignol Biosynthetic Pathway in Jute: Different Gene, Different Consequence

Lignin, a cross-linked macromolecule of hydrophobic aromatic structure, provides additional rigidity to a plant cell wall. Although it is an integral part of the plant cell, presence of lignin considerably reduces the quality of the fiber of fiber-yielding plants. Decreasing lignin in such plants holds significant commercial and environmental potential. This study aimed at reducing the lignin content in jute-a fiber crop, by introducing hpRNA-based vectors for downregulation of two monolignoid biosynthetic genes- cinnamate 4-hydroxylase (C4H) and caffeic acid O-methyltransferase (COMT). Transgenic generations, analyzed through Southern, RT-PCR and northern assays showed downregulation of the selected genes. Transgenic lines exhibited reduced level of gene expression with ~ 16-25% reduction in acid insoluble lignin for the whole stem and ~13-14% reduction in fiber lignin content compared to the control lines. Among the two transgenic plant types one exhibited an increase in cellulose content and concomitant improvement of glucose release. Composition of the lignin building blocks was found to alter and this alteration resulted in a pattern, different from other plants where the same genes were manipulated. It is expected that successful COMT-hpRNA and C4H-hpRNA transgenesis in jute will have far-reaching commercial implications leading to product diversification and value addition.

Microplastics in tourist beaches of Huatulco Bay, Pacific coast of southern Mexico

The presence and impacts of plastic marine debris (PMD) have been documented in the oceans worldwide, and they deserve special attention. This study is the first to report the presence of microplastics in tourist beaches located in Huatulco Bay, southern Mexico. A total of 70 beach sediment samples (for 2 distinct seasons) were collected from Huatulco Bay in April 2013 and December 2014. The samples were subsequently extracted by scanning electron microscopy (SEM) to identify the fibrous microplastics (diameter<5mm). The maximum number of fibrous materials was found in April 2013 and December 2014 in the Rincón Sabroso beach (48/30g sediment) and the Cuatunalco beach (69/30g sediment), respectively. Overall, a high amount of microplastics is present in the Conejos, Tangolunda, Santa Cruz, and San Agustin beaches. The microplastics are mainly derived from tourism-based activities and effluents discharged from the hotels and restaurants located along the beaches.

Correlation between Umbilical Cord Diameter and Cross Sectional Area with Gestational Age and Foetal Anthropometric Parameters

The objective of the study was to find out correlation between umbilical cord diameter, cross sectional area with gestational age and foetal anthropometric parameters. This cross sectional study was conducted among healthy women between the 24(th) and 40(th) completed weeks of a normal pregnancy in the Department of Radiology & Imaging, Mymensingh Medical College Hospital, Mymensingh during the study period, from July 2009 to June 2011. A total of 230 consecutive normal pregnancy patients were included in the study. The diameter & cross-sectional area of the umbilical cord were measured on a plane adjacent to the junction of the umbilical cord and the fetal abdomen, in cross-section, with maximum magnification of the image. The cord was manually circled, and it's cross sectional areas was automatically calculated by the ultrasonograph. The mean±SD age was 24.3±4.7 years with range from 19 to 36 years. The mean gestational age was 32.1±4.5 weeks and more than a half (56.4%) of the pregnant women were nulliparas. A positive significant (p<0.001) correlation were found between umbilical cord diameter with bi-parietal diameter (r=0.548); head circumference (r=0.411); abdominal circumference (r=0.444); femur length (r=0.366) and gestational age gestation age (r=0.643). Similarly, a significant (p<0.001) positive week correlation were found between umbilical cross sectional area with bi-parietal diameter (r=0.3303); head circumference (r=0.3202); abdominal circumference (r=0.2651); femur length (r=0.3307) and gestation age (r=0.4051). A positive significant better correlation was found with umbilical cord diameter than cross sectional area with foetal anthropometric parameters.

Does Education Have Any Influence on Symptom Score of IBS Patients: A Randomized Controlled Study

Despite much research, the pathophysiology of IBS remains poorly understood. So it is very difficult to treat. There is no standard treatment for IBS. Because IBS symptoms can be elicited or exacerbated by diet and stress, this suggests that patient education regarding his or her illness might be beneficial to patients in managing their symptoms. This study was done to see the short term effects of outpatient education in relation to change of symptom score in IBS patients. This is a prospective randomized comparative study. In this study a total of 80 patients were included. Forty patients were given only pharmacological management with Mebevarine hydrochloride 135mg thrice daily half an hour before meal and Amitryptline 10mg at night for six months and another forty were given education in addition to the same pharmacological treatment. In both the study group [medical management only versus medical management with education] changes of symptoms and quality of life of patients of IBS were assessed by using previously used, specially designed symptoms scoring system and a validated IBS-QOL instrument. There was no significant difference in severity of symptoms between only drug treatment group (118.973) and education plus drug treatment group (119.57) before treatment. The difference of improvement between the education group and without education group was not statistically significant (P>0.05), though the subsidence of pain in both the group before and after treatment was statistically significant (P<0.01).

Estimation of Thyroid Hormone in Early Pregnancy and it's Clinical Correlation

This descriptive cross sectional study was done for the estimation of thyroid hormone in early pregnancy and it's clinical correlation. It was conducted at the Antenatal Clinic of Mymensingh Medical College Hospital, Mymensingh from December 2010 to November 2011. Total 185 cases in early pregnancy were taken purposively and randomly. Among the pregnant women, age ranged from 18-42 years with the Mean±SD age 25.77±4.96 years, the gestational weeks ranged 6±1 to 13±1weeks having Mean±SD 9.06± 2.49 weeks. The gravida ranged from primi to 8th gravida Mean±SD 1.89±1.10. Haemoglobin level ranged from 9.0 to 13.2gm/dl; Mean±SD 10.90±0.99gm/dl. Mean±SD of serum FT4 was 17.77±7.25 and Mean±SD of TSH was 3.95±2.94mIU/L. In present study, 5.40% (n=10) of the respondents had hypothyroidism and 0.54% (n=1) showed hyperthyroidism. The present study showed that, the incidence of hypothyroidism had relatively increased then the reference ranges but not statistically significant. But hyperthyroidism was within the reference range. This study showed slightly higher percentage of hypothyroidism in both ≤30 (4.52%) and ≥30 (10%) years of age groups especially a bit higher percentage in the elderly group. In present study, hypothyroidism was common among women of lower income group. Present study showed a higher percentage of stillbirth &miscarriage among study population. This study showed a relatively higher prevalence of abnormal thyroid function (especially hypothyroidism) in the study population and suggests the routine screening of thyroid hormone in early pregnancy in addition to routine antenatal care.

Small Bowel Perforation during Suprapubic Trocar Cystotomy: A Case Report

A 35 years old man presented with retention of urine secondary to meatal stenosis with bulbar urethral stricture. He had a distended, palpable, tender urinary bladder. Urethral catheterization and dilatation was tried but failed. A trocar cystostomy was performed under local anaesthesia, which led to the injury to the small bowel when least expected. This is a rare but well recognized complication of small bowel injury following blind trocar suprapubic cystostomy when it was least expected and as such had a significant bearing on its management. We discuss its subsequent management and possible mechanism underlying this unexpected and unfortunate complication in the given circumstances.

Impact of silver nanoparticles on benthic prokaryotes in heavy metal-contaminated estuarine sediments in a tropical environment

Little knowledge is available about the potential impact of commercial silver nanoparticles (Ag-NPs) on estuarine microbial communities. The Hugli river estuary, India, is susceptible to heavy metals pollution through boat traffic, and there is the potential for Ag-NP exposure via effluent discharged from ongoing municipal and industrial activities located in close proximity. This study investigated the effects of commercial Ag-NPs on native microbial communities in estuarine sediments collected from five stations, using terminal restriction fragment length polymorphism (T-RFLP) technique. An increase in the number of bacteria in consortium in sediments was observed following exposure to Ag-NPs. In general microbial communities may be resistant in estuarine systems to the antimicrobial effects of commercial Ag-NPs, but key microorganisms, such as Pelobacter propionicus, disappeared following exposure to Ag-NPs. In conclusion, the T-RFLP analysis indicated that Ag-NPs have the potential to shape estuarine sediment bacterial community structure.

Bioaccumulation of metals in fish species from water and sediments in macrotidal Ennore creek, Chennai, SE coast of India: A metropolitan city effect

Accumulation of trace metals (Fe, Mn, Cr, Cu, Ni, Co, Pb, Zn, Cd) were investigated in water, sediment (n=20) along with six fish of diverse feeding guilds (Sillago sihama, Liza parsia, Etroplus suratensis, Oreochromis mossambicus, Arius parkii and Gerres oyena) from the Ennore creek, northern part of Chennai metropolitan megacity, southeast coast of India. Dissolved trace metals (DTMs) in surface water samples and total trace metals (TTMs) in surface sediments (top 0-10cm) indicate that concentration pattern of metals was higher in the discharge point of the river/channels entering the main creek. The maximum mean values of DTMs exhibited the following decreasing order (expressed in µg/L): Fe (1698)>Mn (24)>Zn (14.50)>Pb (13.89)>Ni (6.73)>Cu (3.53)>Co (3.04)>Cr (2.01) whereas the trend is somewhat different in sediments (µgg(-1)): Fe (4300)>Mn (640)>Cr (383)>Zn (155)>Cu (102)>Ni (35)>Pb (32)>Cd (0.51) are mainly due to the industrial complexes right on the banks of the river/channels. Species-specific heterogeneous patterns of tissue metal loads were apparent and the overall metal enrichment exhibited the following decreasing order (expressed in µgg(-1)): Cu (7.33)>Fe (6.53)>Zn (4.91)>Cr (1.67)>Pb (1.33)>Ni (0.44)>Mn (0.43)>Co (0.36)>Cd (0.11). This indicates that metals are absorbed onto the different organs, which is also endorsed by the calculated values of bioaccumulation factor (BAFs) (avg. muscle 117, gill 126, liver 123, intestine 118) in fishes. The high calculated biota sediment accumulation factor (BSAF) (0.437) for the species Arius parkii is considered to be a potential bioindicator in this region. The enrichment of trace metals is also supported by the association of metals in water, sediments and different body organs (muscle, gill, liver, intestine) of fish samples. Comparative studies with other coastal regions indicate considerable enrichment of DTMs & TTMs in sediments as well as in various organs of fish samples. Holistic spatial, temporal monitoring and comprehensive regional strategies are required to prevent health risks and ensure nutritional safety conditions.

A chemical status predictor. A methodology based on World-Wide sediment samples

As a consequence of the limited resources of underdeveloped countries and the limited interest of the developed ones, the assessment of the chemical quality of entire water bodies around the world is a utopia in the near future. The methodology described here may serve as a first approach for the fast identification of water bodies that do not meet the good chemical status demanded by the European Water Framework Directive (WFD). It also allows estimating the natural background (or reference values of concentration) of the areas under study using a simple criterion. The starting point is the calculation the World-Wide Natural Background Levels (WWNBLs) and World-Wide Threshold Values (WWTVs), two indexes that depend on the concentration of seven elements present in sediments. These elements, As, Cd, Cr, Cu, Ni, Pb and Zn, have been selected taking into account the recommendations of the UNEP (United Nations Environment Programme) and USEPA (United States Environmental Protection Agency), that describe them as elements of concern with respect to environmental toxicity. The methodology has been exemplified in a case study that includes 134 sediment samples collected in 11 transitional water bodies from 7 different countries and 4 different continents. Six of the water bodies considered met the good chemical status demanded by the WFD. The rest of them exceeded the reference WWTVs, at least for one of the elements. The estuaries of the Nerbioi-Ibaizabal (Basque Country) and Cavado (Portugal), the sea inlet of Río San Pedro (Spain), the Sepetiba Bay (Brazil) and the Yucateco lagoon (Mexico) belong to that group.

YnfA , a SMR family efflux pump is abundant in Escherichia coli isolates from urinary infection

A quantitative study was undertaken to determine the expression level of different efflux pumps in multi-drug-resistant (MDR) Escherichia coli isolates from urinary infection. We have determined the presence of different efflux pumps and measured the expression level of tolC, mdfA, norE and ynfA genes among 48 isolates by quantitative real-time PCR. The expression level of tolC and ynfA was constantly high and observed among 75-80% of isolates, whereas mdfA and norE were expressed occasionally. Our findings suggest that ynfA, a new SMR efflux pump gene family member increases the antibiotics' resistance in E. coli.

PA1 An internal audit into the adequacy of pain assessment in a hospice setting

BACKGROUND

Pain is the most common presenting symptom of patients referred to palliative services. The effective management of pain is therefore paramount to any palliative service. The SOCRATES mnemonic is a pain assessment framework that is widely used by healthcare professionals to help them to remember to ask about key questions concerning a patient's pain. The eight elements of this framework are Site, Onset, Character, Radiation, Associated Factors, Timing, Exacerbating and Relieving Factors and Severity.

AIM

To assess whether 100% of patients admitted to the hospice in a three month period with pain as a symptom were fully assessed using all elements of the SOCRATES mnemonic. Furthermore to ensure whether these patients were written up for regular and breakthrough analgesia medication.

METHODS

New admissions from February to April were identified using SystmOne™ and their records searched for mention of pain as a symptom and a score assigned according to the number of elements of SOCRATES used. The medications section on SystmOne™ was checked for the prescription of analgesia.

RESULTS

The results revealed that 0% of patients were fully assessed using all elements of the SOCRATES mnemonic and 66.7% of patients were partially assessed. The mean average of SOCRATES elements used when assessing pain was 3.3. Regular and breakthrough analgesia were prescribed for 100% of patients who complained of pain.

CONCLUSION

This hospice meets standards for prescribing analgesia, however significantly falls below standards on the assessment of pain using all elements of the SOCRATES mnemonic.

Facile and green synthesis of CdSe quantum dots in protein matrix: tuning of morphology and optical properties

Herein, we have demonstrated a facile and green approach for the synthesis of Cadmium selenide (CdSe) quantum dots (QDs). The process was mediated by bovine serum albumin (BSA) and it was found that BSA plays the dual role of reducing agent as well as a stabilizing agent. The QDs exhibited sharp excitonic absorption features at ~500 nm and subsequently showed reasonably good photoluminescence (PL) at room temperature. The PL is seen to be strongly dependent on the concentration of the precursors and hence, the luminescence of these QDs could be conveniently tuned across the visible spectrum simply by varying molar ratio of the precursors. It can be envisaged from the fact that a red-shift of about 100 nm in the PL peak position was observed when the molar ratio of the precursors ([Cd2+]:[Se2-], in mM) was varied from 10:5 to 10:40. Subsequently, the charge carrier relaxation dynamics associated with the different molar ratio of precursors has been investigated and very interesting information regarding the energy level structures of these QDs were revealed. Most importantly, in conjunction with the optical tuning, the nanomorphology of these nanoparticles was found to vary with the change in molar ratios of Se and Cd precursors. This aspect can provide a new direction of controlling the shape of CdSe nanoparticles. The possible mechanism of the formation as well as for the shape variation of these nanoparticles with the molar ratios of precursors has been proposed, taking into account the role of amino acid residues (present in BSA). Moreover, the QDs were water soluble and possessed fairly good colloidal stability therefore, can have potential applications in catalysis and bio-labeling. On the whole, the present methodology of protein assisted synthesis is relatively new especially for semiconducting nanomaterials and may provide some unique and interesting aspects to control and fine tune the morphology vis-à-vis, their optical properties.

Macro-anatomical variation of the olfactory apparatus in some Indian teleosts with special reference to their ecological habitat

The anatomy of the peripheral olfactory apparatus (i.e. olfactory lamellae, olfactorychambers, accessory nasal sacs, olfactory nerve tracts, olfactory bulbs and brain) of some teleosts, viz. Pseudapocryptes lanceolatus (Bloch and Schneider, 1801) - an air breathing mudskipper, Lepidocephalichthys guntea (Hamilton, 1822) - a freshwater scavenger fish and Mastacembelus armatus (Lacepède, 1800) - a freshwater potamodromous fish, has been studied in relation to their specific ecological habitat. Live, adult, sex-independent fish species were collected from the local markets of West Bengal, India, and acclimatised with the laboratory conditions (for 72 h at 32°C). The specimens were anaesthetised by MS-222 (dose: 100-200 mg/L). Olfactory apparatuses were dissected out and fixed inaqueous Bouin's solution. The macro- and microstructures (using haematoxylin and eosin) of the olfactory apparatuses were examined under binocular light microscope (LM) and trinocular LM (Primo Star; Carl Zeiss Microscpy, GmbH, Germany) respectively. P. lanceolatus possesses unilamellar olfactory apparatus at therounded snout, whereas L. guntea shows small rosette with 18 to 24 lamellae oneither side of the elliptical snout. Elongated olfactory rosette (number of lamellae ranges from 60 to 76) is present at the pointed snout of M. armatus. Morpho-anatomical variation in snout structure of the respective species is an indicative of divergence in ecological habitat, but variation in olfactory apparatus is significant for species-specific differentiation. Pseudostratified olfactory neuroepithelial components (i.e. sensory receptor cell, supporting cell and basal cell) show striking similarities amongst these species. Therefore comparative anatomical changes of the snout and olfactory apparatus are not only representing ecological habitat based on interspecific variation, but may also indicate the phylogenetic relation amongst said species.

Influence of body mass index on low back pain

Low back pain (LBP) is a common problem affecting 70% of the population in the developed countries and prevalence is also increasing in the developing countries. We conducted a clinic based cross-sectional study in the city of Dhaka and Chittagong during the period of January 2009 to December 2011. Participants (n=357) were interviewed and examined through a structured questionnaire after a non purposive sampling to explore the influence of body mass index (BMI) on LBP. BMI was assessed by the equation weight (Kg)/hight² (m²) and LBP was assessed by modified visual analogue scale. Association between LBP and BMI was tested by Chi-square test. Among 357 patients the incidence of LBP was common in the age group between 40-59 years and it was 172(48.17%) followed by 60-79, 20-39 and ≥80 years group with 21.29%, 17.65% and 12.89% respectively. Female presented more with LBP, i.e. 196(54.91%) than the male 161(45.09%). The more study population was found to have BMI within normal range, i.e. 167(46.78%). This was followed by overweight group which amounted 137(38.37%) while the obese group was the least, i.e. 53(14.85%). Maximum study population presented with severe LBP which amounted 140(39.22%) while others presented with moderate and mild LBP and amounting 118(33.05%) and 99(27.73%) respectively. Among the normal BMI group most patient presented with mild pain (n=82) followed by moderate (n=55) and severe (n=30) pain. Participants with overweight presents with severe pain mostly (n=58) but obese participants presented with severe low back pain (n=25). Statistically the association of LBP with BMI was found to be highly significant (p<0.0001). In this study, 137(46.78%) participants of normal BMI presented with LBP but majorities (n=82) presented with mild LBP and overweight and obese participants mostly presented with severe LBP. On the basis of these findings, careful evaluation of risk factors and deliberate assessment of the therapeutic as well as preventive measure for the management of patient of LBP is highly recommended.

Neutron diffraction evidence for kinetic arrest of first order magneto-structural phase transitions in some functional magnetic materials

Neutron diffraction measurements, performed in the presence of an external magnetic field, have been used to show structural evidence for the kinetic arrest of the first order phase transition from (i) the high temperature austenite phase to the low temperature martensite phase in the magnetic shape memory alloy Ni37Co11Mn42.5Sn9.5, (ii) the higher temperature ferromagnetic phase to the lower temperature antiferromagnetic phase in the half-doped charge ordered compound La0.5Ca0.5MnO3 and (iii) the formation of glass-like arrested states in both compounds. The cooling and heating under unequal fields protocol has been used to establish phase coexistence of metastable and equilibrium states, and also to demonstrate the devitrification of the arrested metastable states in the neutron diffraction patterns. We also explore the field–temperature dependent kinetic arrest line TK(H), through the transformation of the arrested phase to the equilibrium phase. This transformation has been observed isothermally in reducing H, as also on warming in constant H. TK is seen to increase as H increases in both cases, consistent with the low-T equilibrium phase having lower magnetization.

Metal concentrations in sediments from tourist beaches of Miri City, Sarawak, Malaysia (Borneo Island)

Forty-three sediment samples were collected from the beaches of Miri City, Sarawak, Malaysia to identify the enrichment of partially leached trace metals (PLTMs) from six different tourist beaches. The samples were analyzed for PLTMs Fe, Mn, Cr, Co, Cu, Ni, Pb, Sr and Zn. The concentration pattern suggest that the southern side of the study area is enriched with Fe (1821-6097 μg g(-1)), Mn (11.57-90.22 μg g(-1)), Cr (51.50-311 μg g(-1)), Ni (18-51 μg g(-1)), Pb (8.81-84.05 μg g(-1)), Sr (25.95-140.49 μg g(-1)) and Zn (12.46-35.04 μg g(-1)). Compared to the eco-toxicological values, Cr>Effects range low (ERL), Lowest effect level (LEL), Severe effect level (SEL); Cu>Unpolluted sediments, ERL, LEL; Pb>Unpolluted sediments and Ni>ERL and LEL. Comparative results with other regions indicate that Co, Cr, Cu, Ni and Zn are higher, indicating an external input rather than natural process.

Sea urchin like shaped cdse nanoparticles grown in aqueous solutions via electron beam irradiation

Cadmium selenide (CdSe) nanoparticles have been grown from an aqueous solutions containing equimolar ammoniated cadmium sulphate and sodium selenosulphate as precursors in presence of citric acid as a capping agent, via electron beam irradiation. The radiolytic processes occurring in the medium result in the formation of CdSe nanoparticles through the reactions mediated by hydrated electrons (e(aq)-). The dynamics of the formation of these nanoparticles was investigated by pulse radiolysis studies. The size of the primary nanoparticles as estimated from the absorption spectra recorded immediately was less than 3 nm. These nanoparticles exhibited strong excitonic absorption pattern and broad photoluminescence at room temperature, which has been attributed to the presence of surface states/defects. This has been confirmed by Raman spectral studies, where CdSe nanoparticles exhibited characteristic surface phonon modes at around 250 cm(-1). The photoluminescence lifetime decay measurements further supported the existence of surface defects on the as-grown CdSe nanoparticles. These nanoparticles were found to exist in the agglomerated form of sea urchin like shapes of uniform size of about 500 nm as revealed from TEM and SEM images. These sea urchin like shaped CdSe nanoparticles grown in this route were found to be very stable under the ambient conditions. We infer that citric acid influences the growth as well as stability of these nanoparticles. It is expected that these nanomaterials could find potential applications in the field of sensors, catalysis and photovoltaics.

Chromium (VI) induced acute toxicity and genotoxicity in freshwater stinging catfish, Heteropneustes fossilis

Acute toxicity and genotoxicity of Chromium(VI) as K2Cr2O7 were evaluated in freshwater stinging catfish, Heteropneustes fossilis. Fish showed behavioral alterations after K2Cr2O7 exposure and 96h-LC50 was 35.724mg/L in semi-static bioassay. Fish were exposed to three sub-lethal concentrations (concentration I=1/4th of 96h-LC50, concentration II=1/10th of 96h-LC50 and concentration III=environmental concentration of Cr reported in the river Buriganga). Blood, liver and gill samples were collected after 48h, 96h and 192h. Micronucleus (MN) assay was conducted in blood erythrocytes and DNA damage was evaluated by comet assay in whole blood, gill and liver tissues. Cr(VI) significantly (p<0.05) induced MN frequency and tail DNA (percent) which increased in a concentration depended manner in all types of tissues. Frequency of MN and tail DNA (percent) increased after 48 and 96h of exposure which decreased after 192h of exposure. The liver was the most sensitive to chromium (VI) exposure among the tissues with highest tail DNA (33.70±0.68 percent) at 9.0mg/L after 96h. This study found MN and comet assays in combination as an adequate approach for ecotoxicological monitoring and Cr(VI) as potential genotoxic agent.

Arsenic speciation in polychaetes (Annelida) and sediments from the intertidal mudflat of Sundarban mangrove wetland, India

This paper documents the concentration of total arsenic and individual arsenic species in four soft-bottom benthic polychaetes (Perenereis cultifera, Ganganereis sootai, Lumbrinereis notocirrata and Dendronereis arborifera) along with host sediments from Sundarban mangrove wetland, India. An additional six sites were considered exclusively for surface sediments for this purpose. Polychaetes were collected along with the host sediments and measured for their total arsenic content using inductively coupled plasma mass spectrometry. Arsenic concentrations in polychaete body tissues varied greatly, suggesting species-specific characteristics and inherent peculiarities in arsenic metabolism. Arsenic was generally present in polychaetes as arsenate (As(V) ranges from 0.16 to 0.50 mg kg(-1)) or arsenite (As(III) ranges from 0.10 to 0.41 mg kg(-1)) (30-53 % as inorganic As) and dimethylarsinic acid (DMA(V) <1-25 %). Arsenobetaine (AB < 16 %), and PO(4)-arsenoriboside (8-48 %) were also detected as minor constituents, whilst monomethylarsonic acid (MA(V)) was not detected in any of the polychaetes. The highest total As (14.7 mg kg(-1) dry wt) was observed in the polychaete D. arborifera collected from the vicinity of a sewage outfall in which the majority of As was present as an uncharacterised compound (10.3 mg kg(-1) dry wt) eluted prior to AB. Host sediments ranged from 2.5 to 10.4 mg kg(-1) of total As. This work supports the importance of speciation analysis of As, because of the ubiquitous occurrence of this metalloid in the environment, and its variable toxicity depending on chemical form. It is also the first work to report the composition of As species in polychaetes from the Indian Sundarban wetlands.

Larval abundance and its relation to macrofouling settlement pattern in the coastal waters of Kalpakkam, southeastern part of India

The present work revealed that salinity, water temperature, and food availability were the most crucial factors affecting the abundance of larvae and their settlement as macrofouling community in the coastal waters of Kalpakkam. Quantitative as well as qualitative results showed that late post-monsoon (April-May) and pre-monsoon (June-September) periods were found to be suitable periods for larval growth, development, and survival to adult stages for most of the organisms. Clustering of physico-chemical and biological (including larval and adult availability) data yielded two major clusters; one formed by northeast (NE) monsoon months (October-January) and the other by post-monsoon/summer (February-May) months, whereas; pre-monsoon months (June-September) were distributed between these two clusters. Among all the major macrofouler groups, only bivalves established a successful relationship between its larval abundance and adult settlement. Principal component analysis indicated good associations of bivalve larvae with polychaete larvae and adult bivalves with adult barnacles. However, biotic relation between ascidians and bryozoans was observed both in the larval as well as adult community.

Oxidation reactions of thymol: a pulse radiolysis and theoretical study

The reactions of (•)OH and O(•-), with thymol, a monoterpene phenol and an antioxidant, were studied by pulse radiolysis technique and DFT calculations at B3LYP/6-31+G(d,p) level of theory. Thymol was found to efficiently scavenge OH radicals (k = 8.1 × 10(9) dm(3) mol(-1) s(-1)) to produce reducing adduct radicals, with an absorption maximum at 330 nm and oxidizing phenoxyl radicals, with absorption maxima at 390 and 410 nm. A major part of these adduct radicals was found to undergo water elimination, leading to phenoxyl radicals, and the process was catalyzed by OH(-) (or Na(2)HPO(4)). The rate of reaction of O(•-) with thymol was found to be comparatively low (k = 1.1 × 10(9) dm(3) mol(-1) s(-1)), producing H abstracted species of thymol as well as phenoxyl radicals. Further, these phenoxyl radicals of thymol were found to be repaired by ascorbate (k = 2.1 × 10(8) dm(3) mol(-1) s(-1)). To support the interpretation of the experimental results, DFT calculations were carried out. The transients (both adducts and H abstracted species) have been optimized in gas phase at B3LYP/6-31+G(d,p) level of calculation. The relative energy values and thermodynamic stability suggests that the ortho adduct (C6_OH adduct) to be most stable in the reaction of thymol with OH radicals, which favors the water elimination. However, theoretical calculations showed that C4 atom in thymol (para position) can also be the reaction center as it is the main contributor of HOMO. The absorption maxima (λ(max)) calculated from time-dependent density functional theory (TDDFT) for these transient species were close to those obtained experimentally. Finally, the redox potential value of thymol(•)/thymol couple (0.98 V vs NHE) obtained by cyclic voltammetry is less than those of physiologically important oxidants, which reveals the antioxidant capacity of thymol, by scavenging these oxidants. The repair of the phenoxyl radicals of thymol with ascorbate together with the redox potential value makes it a potent antioxidant with minimum pro-oxidant effects.

A simple method of DNA isolation from jute (Corchorus olitorius) seed suitable for PCR-based detection of the pathogen Macrophomina phaseolina (Tassi) Goid

A simple method was developed for isolating DNA from jute seed, which contains high amounts of mucilage and secondary metabolites, and a PCR protocol was standardized for detecting the seedborne pathogen Macrophomina phaseolina. The cetyl trimethyl ammonium bromide method was modified with increased salt concentration and a simple sodium acetate treatment to extract genomic as well as fungal DNA directly from infected jute seed. The Miniprep was evaluated along with five other methods of DNA isolation in terms of yield and quality of DNA and number of PCR positive samples. The Miniprep consistently recovered high amounts of DNA with good spectral qualities at A260/A280. The DNA isolated from jute seed was found suitable for PCR amplification. Macrophomina phaseolina could be detected by PCR from artificially inoculated as well as naturally infected jute seeds. The limit of PCR-based detection of M. phaseolina in jute seed was determined to be 0·62 × 10(-7) CFU g(-1) seed.

A primary spinal hydatid cyst

Hydatid disease occurs in humans as a result of faeco-oral contamination. Spinal hydatid cyst is a rare entity and a serious form of hydatid disease affecting less than 1% of the total cases of hydatid disease. Neural compression is common in vertebral hydatidosis where prognosis is always considered as very poor. Difficulty in management due to recurrence of this rare entity makes it a challenging disease to eradicate entirely. Efficacy of use of anthelminthic even after complete surgical removal is yet to be established. We are reporting diagnosis and management of a case of primary extradural and paraspinal hydatid cyst (HC) in an otherwise healthy patient who did not show any other evidence of systemic hydatid disease. The diagnosis was recognized preoperatively by magnetic resonance imaging (MRI) and confirmed postoperatively by histopathology. Surgical removal of the cysts/lesions was followed by anti-helminthic medication and recovery was satisfactory until the patient had recurrence after one year. The patient underwent surgery for the second time and was given anti-helminthic again for a longer period and was recurrence free for the next one year.

Development of high-voltage pulse-slicer unit with variable pulse duration for pulse radiolysis system

A high-voltage pulse-slicer unit with variable pulse duration has been developed and integrated with a 7 MeV linear electron accelerator (LINAC) for pulse radiolysis investigation. The pulse-slicer unit provides switching voltage from 1 kV to 10 kV with rise time better than 5 ns. Two MOSFET based 10 kV switches were configured in differential mode to get variable duration pulses. The high-voltage pulse has been applied to the deflecting plates of the LINAC for slicing of electron beam of 2 μs duration. The duration of the electron beam has been varied from 30 ns to 2 μs with the optimized pulse amplitude of 7 kV to get corresponding radiation doses from 6 Gy to 167 Gy.

Metal concentrations in water and sediments from tourist beaches of Acapulco, Mexico

A survey on the metal concentrations (As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sr, V, Zn) in beach water and sediments is reported from the tourist destination of Acapulco city on the Pacific coast of Mexico. The concentration of dissolved trace metals (DTMs) in beach water and acid leachable trace metals (ALTMs) in sediments indicated that they are anthropogenic in nature due to the increased tourist activities in the crowded beach locations. The statistical analysis indicates Fe and Mn play a major role as metal scavengers in both the medium (water and sediment) and the higher value of other metals is site specific in the study area, indicating that they are transported from the local area. Comparison results suggest that the beach water quality has deteriorated more than the sediments and special care needs to be taken to restore the beach quality.

Trace metal bioaccumulation by soft-bottom polychaetes (Annelida) of Sundarban Mangrove Wetland, India and their potential use as contamination indicator

Bioaccumulation of trace metals in four soft-bottom polychaetes along with the host sediments was recorded from the intertidal regions of Indian Sundarban mangrove wetland. The enrichment of Mn (maximum 730 mg kg⁻¹) and Zn (maximum 320 mg kg⁻¹) was recorded for all the polychaetes followed by Cr, Cu, As, Co, Ni and Pb, showing sharp variations between the species. However, concentrations of Sn and Hg were very low with small variations between the species. An overall high bioconcentration factor (BCF) was recorded in the capitellid worm Mastobranchus indicus. The results of the investigation indicate the possibility of developing a standard test protocol for bioaccumulation by polychaetous annelids.

Quantification and source identification of polycyclic aromatic hydrocarbons in core sediments from Sundarban mangrove wetland, India

The distribution and potential sources of 16 polycyclic aromatic hydrocarbons (PAHs) in sediment cores (<63 microm particle size) of the Sundarban mangrove wetland, northeastern coast of Bay of Bengal (India), were investigated by gas chromatography coupled to mass spectrometry. The total concentrations of 16 PAHs ( summation operator(16)PAHs) ranged from 132 to 2938 ng/g, with a mean of 634 ng/g, and the sum of 10 out of 16 priority PAHs ( summation operator(10)PAH) varied from 123 to 2441 ng/g, with a mean of 555 ng/g, and the 5 carcinogenic PAHs (benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, indeno[1,2,3-cd]pyrene, and dibenz[a,h]anthracene) accounted for 68-73% of the priority PAHs. Maximum concentrations of the sediment core were obtained at subsoil depth of 12-16 cm. The prevalence of four to six aromatic ring PAHs and cross-plots of specific isomer ratios such as phenanthrene/anthracene, fluoranthene/pyrene, and methylphenanthrenes/phenanthrene suggested the predominance of wood and coal combustion sources, the atmospheric deposition, and surface runoff to be the major transport pathways. A good correlation existed between the benzo[a]pyrene level and the total PAH concentrations, making this compound a potential molecular marker for PAH pollution. Total TEQ (S) (carc) values calculated for samples varied from 6.95 ng/g TEQ (S) (carc) to 119 ng/g TEQ (S) (carc) , with an average of 59 ng/g dry weight TEQ (S) (carc) . The baseline data can be used for regular monitoring, considering the industrial and agricultural growth around this coastal environment.

Seasonal variation in physicochemical properties of coastal waters of Kalpakkam, east coast of India with special emphasis on nutrients

A study pertaining to the seasonal variation in physicochemical properties of the coastal waters was carried out at Kalpakkam coast for a period of 1 year (February 2006 to January 2007). It revealed that the coastal water was significantly influenced by freshwater input during North East (NE) monsoon and post-monsoon periods. Concentration of all the nutrients and dissolved oxygen (DO) was relatively high during the NE monsoon, whereas, salinity and chlorophyll-a (chl-a) were at their minimum level during this period. Phytoplankton production peak was observed in summer during which a typical marine condition prevailed. The present observed values of nitrate, phosphate, silicate, and turbidity are significantly high (five to ten times) compared to that of the pre-Tsunami period from this coast. Relatively low DO and chl-a concentration was noticed during the post-Tsunami period. A notable feature of this study is that though nutrient concentration in the coastal waters during post-Tsunami period has increased significantly, turbidity, the most single dominating factor, was found to adversely affect the phytoplankton production during post-Tsunami period as reflected by relatively low chl-a concentration. Thus, the post-Tsunami period may result in a change in coastal biodiversity pattern concomitant with change in coastal water quality.

Acid leachable trace metals in sediment cores from Sunderban Mangrove Wetland, India: an approach towards regular monitoring

The paper presents the first document to identify the enrichment pattern of acid leachable trace metals (ALTMs) such as Fe, Mn, Cr, Cu, Ni, Pb, Cd, Co, Mo, Ag, As and Ba and their relationship with sediment quality parameters (pH, organic carbon, carbonates and texture) in core sediments (<63 microm particle size) from Indian Sunderban mangrove wetland, formed at the estuarine phase of the river Hugli (Ganges). Textural analysis reveals an overall predominance of mud. The results indicate that the change in pH values causes coagulation and precipitation of ALTMs. Fe and Mn have fairly close distribution patterns of enrichment in surface layers which might be ascribed to early diagnetic processes. The most prominent feature of ALTMs is the enrichment of Fe, Mn, Cr, Cu, Ni, Pb, and Ba in the surface-subsurface layers in the sediment cores, which is mainly attributed to the intense industrial and agricultural activities as well as drainage of untreated domestic sewage to this coastal region. The ALTMs also indicate their association with organic carbon and Fe-Mn oxyhydroxides. The enrichment is well--supported by the correlation, grouping and clustering of ALTMs in statistical analyses. Anthropogenic Factor values indicated ALTMs enrichment for all trace metals due to intense anthropogenic activities. Overall higher values of ALTMs in sediments in comparison to other Indian coastal regions indicate that they are mainly due to the uncontrolled anthropogenic activities in this mangrove estuarine complex. Statistical analyses suggest that five ALTMs (Cu, Pb, As, Mo, Ba) are attached to the organic particles and the clustering of elements separately also indicates that they are from external source. The result of the present study suggests the need for a regular monitoring program which will help to improve the quality of this potential wetland.