Powder Bed Thermal Diffusivity Using Laser Flash Three Layer Analysis

The thermal diffusivity of powder bed plays a crucial role in laser powder bed fusion (LPBF) additive manufacturing. The mechanical properties of the parts built by LPBF are immensely influenced by the thermal properties of the powder bed. This study aims to measure the thermal diffusivity of metallic powder, nickel-based super alloy Inconel718 (IN718), in LPBF using laser flash three-layered analysis in a DLF1600 instrument, which incorporates a special powder cell to encapsulate the powdered sample. Measurements were performed at different temperatures. The thermal diffusivity of several reference samples was measured for the purpose of validating the test results, and it was compared to published data for identical measures. It was observed that experimental results for powder samples were smaller than the actual thermal diffusivity of the sample. R software analysis was used to analyze test data in order to obtain powder thermal diffusivity values that were close to the actual values.

Powder Spreading Mechanism in Laser Powder Bed Fusion Additive Manufacturing: Experiments and Computational Approach Using Discrete Element Method

Laser powder bed fusion (LPBF) additive manufacturing (AM) has been adopted by various industries as a novel manufacturing technology. Powder spreading is a crucial part of the LPBF AM process that defines the quality of the fabricated objects. In this study, the impacts of various input parameters on the spread of powder density and particle distribution during the powder spreading process are investigated using the DEM (discrete element method) simulation tool. The DEM simulations extend over several powder layers and are used to analyze the powder particle packing density variation in different layers and at different points along the longitudinal spreading direction. Additionally, this research covers experimental measurements of the density of the powder packing and the powder particle size distribution on the construction plate.

Study on Body Mass Index, Serum Total Cholesterol and Serum Triglycerides in Adult Male Hypertensive Patients

Hypertension or elevated blood pressure is a serious medical condition that significantly increases the risks of heart, brain, kidney and other diseases. An estimated 1.28 billion adults aged 30-79 years worldwide have hypertension, most (two-thirds) living in low- and middle-income countries. An estimated 46.0% of adults with hypertension are unaware that they have the condition. In Bangladesh, 21.3 million of the adult population has hypertension and that is 21.0% of total population. About half of them (48.7%) with hypertension are diagnosed and 34.9% are under treatment. One of the global targets for non communicable diseases is to reduce the prevalence of hypertension by 33.0% between 2010 and 2030. This study was done to evaluate the effects of hypertension and to find out the major complications occurring due to hypertension. This analytical type of cross sectional study was carried out in the Department of Physiology, Mymensingh Medical College, Mymensingh, Bangladesh from January 2021 to December 2021. A total number of 120 male subjects, age ranged from 20-59 years was included in this study. Among them, sixty (60) hypertensive subjects were taken as study group (Group II) and sixty (60) ages matched normotensive adult male subjects were taken as control group (Group I). The results were calculated and analyzed by using Statistical package for social science (SPSS). Anthropometric measurements such as height and weight were taken in meter and kilogram respectively. Systolic and diastolic blood pressure were measured by Aneroid Sphygmomanometer (ALPK2, Japan), laboratory analysis of fasting serum total cholesterol by CHOD-POD method, fasting serum triglycerides by GPO-POD method. In this study we found that in study group Mean±SD of body mass index (29.36±2.60, p<0.001), fasting serum total cholesterol (232.05±11.18, p<0.001) and fasting serum triglycerides (180.67±19.44, p<0.001) which were significantly increased with comparison to control group. It's concluded from this study we recommended that routine estimation of these parameters is important for prevention of complication related to hypertension for leading a healthy life.

Demonstration of microbiological status of fresh fruits and determining the efficiency of different decontaminating agents against the isolated bacteria

Consumption of fresh fruits increases along with the promotion of healthier lifestyles. However, many foodborne illnesses have been reported due to the consumption of contaminated fruits. Fresh produces are subjected to various treatments for minimizing these outbreaks. The present study demonstrates the role of various simple household methods including water washing and some other common chemical treatments for the removal of bacterial load. By performing the spread plate technique, total heterotrophic bacteria, Escherichia coli, Staphylococcus spp., Salmonella spp. and Listeria spp. were determined in 60 samples of 6 categories including Apple (Malus domestica); Grape (Vitis vinifera); Guava (Psidium guajava); Strawberry (Fragaria ananassa); Indian jujube (Ziziphus mauritiana); Malabar plum (Syzygium cumini) before and after washing with tap water, hot water, 100 mg/L sodium hypochlorite (NaOCl), 50 mg/L calcium lactate, 4% acetic acid and 2 mL/L CleanAva for 20 mins at room temperature. All the tested solutions were found to be effective and reduced bacterial loads in fruits compared to the unwashed fruits samples (P<0.01). Treatment with NaOCl, calcium lactate, acetic acid and CleanAva was the more effective washing technique rather than hot water wash. Two to three log of the bacterial load was reduced when samples were subjected to treatment with chemical decontaminating agents. The efficiency of washing depends on the purity of water, and the types and concentration of the disinfectant solutions. An appropriate washing technique needs to implicate to diminish bacterial load and the risk of foodborne infections caused by fruits.

Forest yield prediction under different climate change scenarios using data intelligent models in Pakistan

This study aimed to develop and evaluate data driven models for prediction of forest yield under different climate change scenarios in the Gallies forest division of district Abbottabad, Pakistan. The Random Forest (RF) and Kernel Ridge Regression (KRR) models were developed and evaluated using yield data of two species (Blue pine and Silver fir) as an objective variable and climate data (temperature, humidity, rainfall and wind speed) as predictive variables. Prediction accuracy of both the models were assessed by means of root mean squared error (RMSE), mean absolute error (MAE), correlation coefficient (r), relative root mean squared error (RRMSE), Legates-McCabe's (LM), Willmott's index (WI) and Nash-Sutcliffe (NSE) metrics. Overall, the RF model outperformed the KRR model due to its higher accuracy in forecasting of forest yield. The study strongly recommends that RF model should be applied in other regions of the country for prediction of forest growth and yield, which may help in the management and future planning of forest productivity in Pakistan.

Detection of microorganisms with antibacterial activities from different industrial wastes and GC-MS analysis of crude microbial extract

Many soil microorganisms' i.e., bacteria and fungi produce secondary metabolites called antibiotics. These are used for the treatment of some of the bacterial, fungal and protozoal diseases of humans. There is a need for isolation of a broad spectrum of antibiotics from microorganisms due to the emergence of antibiotic resistance. In the present study two antibiotic producing bacteria Klebsiella pneumoniae and Bacillus cereus were isolated from pharmaceutical and poultry feed industry of Hattar, Haripur Pakistan. Total 10 waste samples were collected from different industries (Marble, Ghee, Soap, Mineral, Steel, Poultry Feed, Pharmaceutical, Qarshi, Cosmetic and Glass). Thirty-three bacterial strains were isolated from industrial wastes of these ten different industries. Fourteen out of thirty-three bacterial strains exhibited antimicrobial activities against at least one of the test microbes considered in this study including Escherchia coli, Staphylococcus aureus and Salmonella typhi. The bacteria were isolated by standard serial dilution spread plate technique. Morphological characterization of the isolates was done by Gram staining. Nine bacterial isolates out of fourteen were initially identified as B. cereus and five as K. pneumoniae through biochemical characterization. The antibacterial activities were tested by well diffusion method. Maximum number of antibiotic producing bacteria were isolated from pharmaceutical and poultry feed industry based on the results of primary screening, the most potential isolates S9, S19, S20, S22 and S23 were selected for secondary screening. The maximum activity against E. coli and S. aureus was recorded by bacterial isolate S19 i.e zones of inhibition of 6.5mm and 9mm while S20 showed 7.5mm and 6mm zones respectively. Molecular identification was carried out on the basis of 16S rRNA sequence analysis. Finally, the isolates were identified as B. cereus accession number LC538271and K. pneumoniae accession number MT078679. Analysis of bacterial extract S20 through GC-MS indicated the presence of 8 compounds of diverse nature and structure. Present study suggests that wastes of pharmaceutical and poultry feed industry may have antibiotic producing bacteria. These bacteria could be utilized for the production of antibiotics. B. cereus and K. pneumoniae isolated from wastes of poultry feed and pharmaceutical industries have the potential to produce antibiotics and could be used to control the microbial growth.

Genetic similarities and phylogenetic analysis of Muntjac (Muntiacus spp.) by comparing the nucleotide sequence of 16S rRNA and cytochrome B genome

This study aimed to identify the phylogenetic similarities among the muntjac (Muntiacus spp.). The phylogenetic similarities among seven major muntjac species were studied by comparing the nucleotide sequence of 16s rRNA and cytochrome b genome. Nucleotide sequences, retrieved from NCBI databases were aligned by using DNASTAR software. A phylogenetic tree was created for the selected species of muntjac by using the maximum likelihood method on MEGA7 software. The results of nucleotide sequences (16s rRNA) showed phylogenetic similarities between, the M. truongsonensis and M. rooseveltorum had the highest (99.2%) while the lowest similarities (96.8%) found between M. crinifrons and M. putaoensi. While the results of nucleotide sequences (Cty b) showed the highest similarity (100%) between M. muntjak and M. truongsonensis and the lowest s (91.5%) among M. putaoensis and M. crinifrons. The phylogenetic tree of muntjac species (16s rRNA gene) shows the main two clusters, the one including M. putaoensis, M. truongsonensis, M. rooseveltorum, and M. muntjak, and the second one including M. crinifrons and M. vuquangensis. The M. reevesi exists separately in the phylogenetic tree. The phylogenetic tree of muntjac species using cytochrome b genes shows that the M. muntjak and M. truongsonensis are clustered in the same group.

The Siberian pine growth dynamics in Altai Mountains, China

Climatic factors play an essential role in the growth of tree ring width. In this study, we aimed to evaluate the correlation between climatic variables and tree-ring growth characteristics of Pinus sibirica in Altai mountains, northwestern China. This study being is first of its kind on climate growth analysis of Pinus sibirica in northwestern China. The study showed great potential to understand the species growing under the specific climatic conditions. Total of 70 tree cores collected from three sites in the sampling area, out of which 63 tree cores considered for this study. The effect of climatic variables which was studied include precipitation, temperature and PDSI. Our results showed that Tree Ring Width chronology has a significantly positive correlation with the late winter (March) temperature and significant negative correlation with the July temperatures. A significant correlation was observed with the late summer precipitation whereas no significant relation found with the Palmer Drought Severity Index. These significant correlations with temperature and precipitation suggested that this tree species had the potential for the reconstruction of the past climate in the area.

Comparison of different diagnostic modalities for isolation of Mycobacterium Tuberculosis among suspected tuberculous lymphadenitis patients

Tuberculosis is a communicable disease with high morbidity and mortality rates in developing countries. The study's primary objective is to compare conventional methods such as acid-fast bacillus (AFB) culture and microscopy with rapid diagnostic methods. The secondary objective is to compare histopathological and microbiological findings in suspected patients with tubercular lymphadenitis. A total of 111 samples (August 2018 to September 2019) of lymph nodes were processed for AFB microscopy, AFB cultures, drug-susceptibility testing (DST), histopathology, and Xpert Mycobacterium Tuberculosis (MTB)/resistance to Rifampin (RIF) assays. Out of 111 lymph node samples, 6 (5.4%) were positive for AFB smear microscopy, 84 (75.6%) were positive for AFB culture, 80 (70.7%) were positive on Gene Xpert, and 102 (91.8%) were indicative of tuberculosis for histopathology studies. Mycobacteria growth indicator tube (MGIT) culture positivity was 84 (75.6%) higher than solid Lowenstein-Jensen (LJ) culture 74 (66.6%). Positive cultures underwent phenotypic DST. Two cases were Multidrug-resistant (MDR) on DST, while three cases were Rifampicin resistant on Gene Xpert. The sensitivity of Genexpert was (62%) against the conventional AFB culture method. The poor performance of conventional lymphadenitis diagnostic methods requires early and accurate diagnostic methodology. Xpert MTB/RIF test can help in the treatment of multidrug-resistant TB cases. Nonetheless, rapid and conventional methods should be used for complete isolation of Mycobacterium tuberculosis.

Payment for ecosystem services (PES): a holistic tool for sustainable forest management-a case study from Pakistan

Economic valuation of ecosystem services is a new concept in forest management. Economic valuation provides basis for payment for ecosystem services (PES). Therefore, objective of this study was to evaluate eco-tourism and carbon stock services of the Maindam valley, District Swat, Pakistan. For the carbon stock calculation, a sample size of 155 plots of 0.1 hectare (Ha) was taken using preliminary survey at 95% confidence interval and 10% allowable error. The data for tourism services was collected from owners of all the hotels, 100 tourists and key informants of the area at 10% sampling intensity on pretested questionnaire for twenty years period (1997-2017). Results showed that Miandam valley has carbon stock worth US$ 16,306,000 while the value of eco-tourism was US$ 1,578,458 on annual basis. The results also showed that trend of tourism has drastically declined after the 9/11 incident for foreigners and locals and the situation was further deteriorated during the era of Talibanization or militancy from 2008-2011. This study recommends implementation of PES strategy at the rate of 5%, thus a total of US$ 78,922 can be earned from eco-tourism and carbon crediting in the study area annually, which could play important role in sustainable forest management.

Major threats and habitat use status of Demoiselle crane (Anthropoides virgo), in district Bannu, Pakistan

Cranes are the large and attractive Creatures of nature with long necks, legs, and life-span. Adults of both sexes are the same with similar color patterns. Demoiselle cranes spend most of their lifespan on dry grasses. They are also found around the stream, rivers, shallow lakes, natural wetlands, and depressions. To evaluate the current status of habitat use and major threats a study was conducted in tehsil Domel district Bannu. Line transect method and water quality tests (temperature, PH, contamination of E-coli bacteria) were used. To determine the major threats questionnaire method was used. The whole data was analyzed by using SPSS 21 version. Based on the distribution four study sites were selected and four water samples from each study site were taken. Most sites were moderate to highly degraded except Kashoo and kurram river mixing point which was low degraded with livestock grazing and human activities. Water quality tests showed PH ranges from 7-9, temperature 6.5-8.5, and contamination of E-coli in all samples. The social survey revealed that hunting, habitat degradation, and pollution as major threats. Effective long-term conservation and management in the study area are needed to focus on the protection of disturbance-free habitat.

Identification and crop damage assessment of indian crested porcupine (Hystrix indica) in selected zones of Abbottabad, Pakistan

Indian crested porcupine is the largest rodent pest that damages a wide variety of crops, vegetables, and tree species which ultimately causes huge economic loss in Pakistan, which is an agricultural country. It prefers to live in hilly terrain but common in temperate and tropical forests, shrublands, and grasslands. This study focused on the identification and assessment of crops damaged along with the main precautionary measures used by the local farmers. The data was collected from twenty-four villages of two union councils i.e. Chamhad and Slahad of district Abbottabad. Two types of data (primary and secondary) were collected from the study area. Primary data was collected for identification and estimation calculation of total crop damaged through direct field observation by taking random quadrates in each village of the study area. The damage in the crop was assessed by randomly selecting a quadrate of 1x1 m2 for the wheat, pearl millet, and Sorghum fields. While 4x4 m2 quadrates were taken for maize and vegetables. At least three quadrate samples were taken from each field including one quadrate taken from the center of the field area. In union council Chamhad, damage to maize (11.31%) and wheat (0.73%) by the Indian crested porcupine while in union council Salhad, damage of maize (6.95%) and wheat (1.6%) was observed. In the entire study area, overall damage to maize crop (8.01%) and wheat (0.88%) was calculated. Based on information obtained from the farmers, the Indian porcupine inflicted damage to potato, tomato, cauliflower, chili pepper, turnip, radish, pea, and onion, etc. Secondary data obtained through a questionnaire survey to explore the human porcupine conflict and precautionary measures used by the farmers and landowners. Open and close-ended questionnaires (159) highlighted the presence of Indian crested porcupine in the study area and 96% of the respondents have seen porcupine directly. Many types of precautionary measures were used by the farmers such as fencing, night stay, night firing, and dogs to decrease the crop damage, respondents (63.91%) use guns for hunting. however, due to the largely agricultural area and nocturnal behavior of Indian crested porcupine majority of the respondents (51.57%) did not use any precautionary measure. Biological control of Indian porcupine is recommended in the study area. Farmers should be encouraged and provide incentives and killing through current should be banned while proper hunting license should be issued to overcome overhunting. Scientific studies are required to control the reproduction of porcupine specifically in the more damaged areas.

Seasonal distribution and habitat use preference of Barking deer (Muntiacus vaginalis) in Murree-Kotli Sattian-Kahuta National Park, Punjab Pakistan

Microhabitat factors associated with the habitat of barking deer (Muntiacus vaginalis) were examined and compared between summer and winter seasons. Habitat characteristics and preferred habitat were measured by locating direct and indirect signs. To quantify the habitat utilization of barking deer, each selected study site was sampled for floral diversity from 2015 to 2017. Quadrats were deployed along transect lines to determine seasonal distribution. Barking deer were not evenly distributed across vegetation types in the study area; they occurred more often in the broad-leaved forest than in Chir pine forest, at an elevational range of 550-850 m, in thick vegetation on steep slopes. The most preferred habitat included trees and shrubs with 30% and 69% cover, respectively. Barking deer avoided thicker tree cover, possibly as it hinders movement and escape from predators. No significant difference (χ2 = 6.37, df = 3, p = 0.19) in seasonal vegetation cover was recorded.

An ethno-botanical study of indigenous medicinal plants and their usage in rural valleys of Swabi and Hazara region of Pakistan

An ethnobotanical study was conducted to document indigenous medicinal plants and their usage from knowledgeable and elderly persons in Razzar and Gadoon valley of Swabi and Allai and Tanawal valley of Hazara region of Pakistan during 2016-2019. Several systematic field visits and questionnaire surveys were carried out in selected sites of the study area to gather relevant information from the local community. Rapid assessment method was adopted for data collection by interviewing the local people having enough knowledge of medicinal plants use for treatment of different ailments. UV (UV) formula was applied to calculate the relative importance of medicinal plant species in each site of the study area. In the present study, 221 medicinal plants belonging to 105 families have been reported through 580 respondents (385 males, 138 females and 57 local health healer) from the Swabi and Hazara region. The main sources of herbal medicines were leaves (21%) followed by fruits (21%), seeds (17%), whole plants (14%), roots (9%), bark (9%), flowers (7%) and gum (2%). Mentha spicata L. and Berberis lycium Royle were reported with highest UV (UV) i.e. 0.92 and 0.68 in Razzar tehsil and Gadoon valley of Swabi, whereas Mentha longifolia L and Geranium wallichianum D were reported with highest UV i.e. (0.65) and (0.88) in Allai and Tanawal valley of Hazara region, respectively. It was concluded that Swabi and Hazara region is rich in medicinal plants species and associated traditional knowledge. Moreover, ethno-medicines have played significant role in the indigenous healthcare system of the study area. However, uprooting the entire plant for ethno-medicine is a big threat to conservation of medicinal plants diversity in the study area.

Euphlyctis Cyanophlyctis Schneider, 1799 (Amphibia: Dicroglossidae) in district Lower Dir, Pakistan

Euphlyctis cyanophlyctis (the skittering frog) is one of the most widespread species in Pakistan. Present study was aimed to know the presence of Euphlyctis cyanophlyctis in urban and rural areas of Lower Dir, the North-western Pakistan. A total of 33 frogs were collected, including 15 from rural and 18 from urban areas. The frogs were caught by hands covered with gloves instead of using nets. The collection was managed from August to October 2016 and from April to May 2018. Morphometric analysis, coloration as well as photographs of the frogs have been provided in detail. Skittering frogs were seen frequent in swampy areas near the water bodies. These frogs were mostly seen after sunset.

Distribution of commensal rodents in rain-fed and irrigated areas of Swat district, Khyber Pakhtunkhwa, Pakistan

Distribution pattern and relative abundance of the agricultural rodent pests of rain-fed and irrigated areas of district Swat Khyber Pakhtunkhwa, Pakistan were recorded from April 2011 to November 2013 using wire mesh live traps. A total of 350 rodents (269 Rattus rattus and 81 Mus musculus) were captured under 2268 trap nights (trap success: 0.15). Regression of daily captures on cumulative captures revealed an estimate of 350 rodents from all the sampled structures with an average of 21.8 rodents per crop field. House rats (R. rattus; 76.8% of captures) were numerically dominant in almost all types of agricultural fields, and were significantly different from the mice (Mus musculus; 23.1% of captures). Both species were found together in some fields. The sex ratio revealed that males outnumbered the females in both of the reported species.

Comparative study of immunochromatographic assay (IgM) and widal test for early diagnosis of typhoid fever

Typhoid fever is a severe systemic infection endemic in many developing countries, including Bangladesh. Present study evaluated immunochromatographic test (ICT) and Widal test in the early diagnosis of typhoid fever cases. The study was carried out in the department of Microbiology, Mymensingh Medical College, Mymensingh between July, 2010 and June, 2011, including 200 individuals of different age and sex. Of them, 150 were clinically suspected cases of typhoid fever and 50 age-sex matched controls. Among 150 blood samples from the suspected cases 106(70.7%) were positive for IgM of Salmonella typhi by ICT and 67(44.7%) were positive by Widal test. Whereas, among the 50 controls 4(8%) were positive by ICT and 6(12%) were positive by Widal test. The sensitivity, specificity, positive and negative predictive value of the ICT was found as 83.3%, 92.00%, 91.9% and 83.6% respectively. On the other hand corresponding values for Widal test were of 44.4%, 88%, 80% and 59.5% respectively. Thus, The ICT (IgM) is better alternative to Widal test for early and accurate diagnosis of typhoid fever. The ICT (IgM) is rapid, easy to perform, applicable for field use and highly sensitive and specific for detection of antibodies in patients with typhoid fever.

Enteropathogens associated with acute diarrhea in a tertiary hospital of Bangladesh

Acute diarrheal diseases are great concern throughout the world, as they are responsible for considerable morbidity and mortality, especially in developing countries. The present study was carried out during the period from January' 2011 to December' 2011 in the Department of Microbiology, Mymensingh Medical College. A total of 300 stool specimens were examined by standard laboratory methods for identification of enteropathogens. Rotavirus was detected by Polyacrylamide Gel electrophoresis (PAGE). Different diarrheagenic E. coli (DEC) were detected by Multiplex PCR following standard methods. Of the 300 stool specimens examined, Enteropathpgens were detected in 160(53.5%) cases. Rota virus was detected in 82(27.5%) cases, followed by DEC in 54(18%), Shigella spp. in 8(2.4%), Salmonella spp. in 5(1.6%), Entameoba histolytica in 4(1.5%) and Giardia lamblia in 3(1.0%) cases. Among the DEC, the Enterotoxigenic E. coli (ETEC) was most prevalent (72%, 39/54). The present study revealed a high prevalence of rotavirus and DEC as the predominant causes of diarrhea in this region.

Personalizing Stem Cell Research and Therapy: The Arduous Road Ahead or Missed Opportunity?

The euphoria of stem cell therapy has diminished, allowing scientists, clinicians and the general public to seriously re-examine how and what types of stem cells would effectively repair damaged tissue, prevent further tissue damage and/or replace lost cells. Importantly, there is a growing recognition that there are substantial person-to-person differences in the outcome of stem cell therapy. Even though the small molecule pharmaceuticals have long remained a primary focus of the personalized medicine research, individualized or targeted use of stem cells to suit a particular individual could help forecast potential failures of the therapy or identify, early on, the individuals who might benefit from stem cell interventions. This would however demand collaboration among several specialties such as pharmacology, immunology, genomics and transplantation medicine. Such transdisciplinary work could also inform how best to achieve efficient and predictable stem cell migration to sites of tissue damage, thereby facilitating tissue repair. This paper discusses the possibility of polarizing immune responses to rationalize and individualize therapy with stem cell interventions, since generalized "one-size-fits-all" therapy is difficult to achieve in the face of the diverse complexities posed by stem cell biology. We also present the challenges to stem cell delivery in the context of the host related factors. Although we focus on the mesenchymal stem cells in this paper, the overarching rationale can be extrapolated to other types of stem cells as well. Hence, the broader purpose of this paper is to initiate a dialogue within the personalized medicine community by expanding the scope of inquiry in the field from pharmaceuticals to stem cells and related cell-based health interventions.