Development of Z-scheme bimetallic tungstate-supported nitrogen deficient g-C3N4 heterojunction for the treatment of refractory pharmaceutical pollutants

The binary BMT/ND-GCN-based heterostructure photocatalyst for pharmaceutical industry wastewater treatment.

An artificial synaptic transistor using an α-In2Se3 van der Waals ferroelectric channel for pattern recognition

Despite being widely investigated for their memristive behavior, ferroelectrics are barely studied as channel materials in field-effect transistor (FET) configurations. In this work, we use multilayer α-In₂Se₃ to realize a ferroelectric channel semiconductor FET, i.e., FeS-FET, whose gate-triggered and polarization-induced resistive switching is then exploited to mimic an artificial synapse. The FeS-FET exhibits key signatures of a synapse such as excitatory and inhibitory postsynaptic current, potentiation/depression, and paired pulsed facilitation. Multiple stable conductance states obtained by tuning the device are then used as synaptic weights to demonstrate pattern recognition by invoking a hidden layer perceptron model. Detailed artificial neural network (ANN) simulations are performed on binary scale MNIST data digits, invoking 784 input (28 × 28 pixels) and 10 output neurons which are used in the training of 42 000 MNIST data digits. By updating the synaptic weights with conductance weight values on 18 000 digits, we achieved a successful recognition rate of 93% on the testing data. Introduction of 0.10 variance of noise pixels results in an accuracy of more than 70% showing the strong fault-tolerant nature of the conductance states. These synaptic functionalities, learning rules, and device to system-level simulation results based on α-In₂Se₃ could facilitate the development of more complex neuromorphic hardware systems based on FeS-FETs.

Despite being widely investigated for their memristive behavior, ferroelectrics are barely studied as channel materials in field-effect transistor (FET) configurations.

Sunlight-assisted degradation of textile pollutants and phytotoxicity evaluation using mesoporous ZnO/g-C3N4 catalyst

Accessibility of adequate safe and fresh water for human consumption is one of the most significant issues throughout the world and extensive research is being undertaken to resolve it. Nanotechnology is now an outstanding medium for water treatment and remediation from microorganisms and organic dyes, as compared to conventional treatment methods. For this task graphitic carbon nitride (g-C3N4) is a potential nanomaterial for environmental remediation, but its photogenerated charge carrier recombination rate restricts its use in practical applications. Hence, in the current study, we used a simple one-step calcination method to synthesize various ratios of ZnO/g-C3N4 binary nanocomposites. The band gap of g-C3N4 is 2.70 eV, but it is shifted to 2.60 eV by the 0.75 : 1 ZnO/g-C3N4 binary nanocomposite. Moreover, phase structure, morphology, thermal stability, oxidation state, elemental analysis, and surface area were evaluated using XRD, SEM, TEM, TGA, XPS, and BET analysis. The optimal ZnO loading content was determined and the mechanism of enhanced photocatalytic activity was studied in detail. The photocatalytic efficiency of the best catalyst was employed for the degradation of textile effluent followed by phytotoxicity evaluation using methylene blue (MB), and rhodamine B (RhB) as a model substrate was tested. Furthermore, the textile effluent treatment analysis discovered that the 75 mg concentration of 0.75 : 1 ZnO/g-C3N4 catalyst degraded up to 80% within 120 min and significantly reduced the concentrations of different physico-chemical parameters of textile effluents. These treated effluents have no phytotoxic effects on fenugreek plants, according to a pot study. It was found that the mesoporous 0.75 : 1 ZnO/g-C3N4 catalyst can be used as an effective and low-cost technique for the degradation of azo dyes in textile wastewaters.

Electrical transport and gas sensing characteristics of dielectrophoretically aligned MBE grown catalyst free InAs nanowires

In this report, the precise alignment of catalyst free InAs nanowires (NWs) on pre-patterned Au microelectrodes by dielectrophoresis (DEP) technique for gas sensing applications is presented. The catalyst free InAs NWs have been grown on Si (111) substrate by molecular beam epitaxy (MBE) technique. The effect of dispersing solvents, electrode geometries and gaps, magnitude, frequency and duration of applied voltage etc, has been studied for aligning the InAs NWs by DEP technique. Current-voltage (I-V) measurements on the aligned NWs show linear behavior at room temperature (300 K), which changes to nonlinear at lower temperatures and higher voltages. The nonlinearity at lower temperatures and higher voltages is well explained by a space charge limited current contribution, which further gives a quantitative estimation of free charge carriers and trap density. The DEP aligned NWs exhibit good sensing response upon exposure to 10 ppm NO₂ gas.

Tuning the band gap of hybrid lead free defect perovskite nano crystals for solar cell applications

In recent reports, combinations of lead free organic inorganic halide perovskites have shown significant advances in solar cell devices.

Simulation of an Armoured Vehicle for Blast Loading

Occupant safety in an armoured vehicle is of paramount importance. Most serious threat to armoured vehicles comes in the form of explosion of buried charge or an improvised explosive device. The use of numerical methods in the validation process of light armoured vehicles reduces the number of prototypes required and decreases the design time. This paper elucidates the process by which one such validation using numerical methods was done. The process of finite element method used for simulation of blast is a prominent method of numerical method of simulation. The finite element model (FEM) process starts with discretisation. By discretisation or meshing, Shell (Quad/Tria) and solid (Tetra/Hexa) elements are generated. The FEM thus created is provided with relevant material model / properties and loading and boundary conditions. The loading conditions are adopted from STANAG 4569 Level II standards. Local deformation, global displacement, stresses and time history of displacement of particular areas of interest are obtained as results. Comparison results include the effect of with and without thermal softening under blast. Based on the results and comparison, suggestions regarding re-engineering the vehicle are presented.

Microstructural and Compositional Characterisation of Electronic Materials

<p class="p1"> </p><p class="p2"><span class="s1"> </span>Microstructural and compositional characterisation of electronic materials in support of the development of GaAs, GaN, and GaSb based multilayer device structures is described. Electron microscopy techniques employing nanometer and sub-nanometer scale imaging capability of structure and chemistry have been widely used to characterise various aspects of electronic and optoelectronic device structures such as InGaAs quantum dots, InGaAs pseudomorphic (pHEMT), and metamorphic (mHEMT) layers and the ohmic metallisation of GaAs and GaN high electron mobility transistors, nichrome thin film resistors, GaN heteroepitaxy on sapphire and silicon substrates, as well as InAs and GaN nanowires. They also established convergent beam electron diffraction techniques for determination of lattice distortions in III-V compound semiconductors, EBSD for crystalline misorientation studies of GaN epilayers and high-angle annular dark field techniques coupled with digital image analysis for the mapping of composition and strain in the nanometric layered structures. Also, <em>in-situ </em>SEM experiments were performed on ohmic metallisation of pHEMT device structures. The established electron microscopy expertise for electronic materials with demonstrated examples is presented.</p>

Tailoring the magnetic and magnetoelectric properties of rare earth orthoferrites for room temperature applications

The M(T) curve shows negative magnetization value for samples containing Er ions. The dielectric constant value does not show any anomaly around the magnetic transition temperature. The temperature at which maximum MDE effect observed corresponds to dielectric loss maxima.

Worldwide Reported Use of IV Tissue Plasminogen Activator for Acute Ischemic Stroke

Background and Purpose

Intravenous tissue plasminogen activator is the most effective treatment for acute ischemic stroke, and its use may therefore serve as an indicator of the available level of acute stroke care. The greatest burden of stroke is in low- and middle-income countries, but the extent to which intravenous tissue plasminogen activator is used in these countries is unreported.

Summary of Review

A systematic review was performed searching each country name AND ‘stroke’ OR ‘tissue plasminogen activator’ OR ‘thrombolysis’ using PubMed, Embase, Global Health, African Index Medicus, and abstracts published in the International Journal of Stroke (Jan. 1, 1996–Oct. 1, 2012). The reported use of intravenous tissue plasminogen activator was then analyzed according to country-level income status, total expenditure on health per capita, and mortality and disability-adjusted life years due to stroke. There were 118 780 citations reviewed. Of 214 countries and independent territories, 64 (30%) reported use of intravenous tissue plasminogen activator for acute ischemic stroke in the medical literature: 3% (1/36) low-income, 19% (10/54) lower-middle-income, 33% (18/54) upper-middle-income, and 50% (35/70) high-income-countries (test for trend, P < 0·001). When considering country-level determinants of reported intravenous tissue plasminogen activator use for acute ischemic stroke, total healthcare expenditure per capita (odds ratio 3·3 per 1000 international dollar increase, 95% confidence interval 1·4–9·9, P = 0·02) and reported mortality rate from cerebrovascular disease (odds ratio 1·02, 95% confidence interval 0·99–1·06, P = 0·02) were significant, but reported disability-adjusted life years from cerebrovascular diseases and gross national income per capita were not ( P > 0·05). Of the 10 countries with the highest disability-adjusted life years due to stroke, only one reported intravenous tissue plasminogen activator use.

Conclusions

By reported use, intravenous tissue plasminogen activator for acute ischemic stroke is available to some patients in approximately one-third of countries. Access to advanced acute stroke care is most limited where the greatest burden of cerebrovascular disease is reported.

Susac syndrome: clinical characteristics and treatment in 29 new cases

BACKGROUND AND PURPOSE

  There are few clinical studies on the attempted treatments and outcomes in patients with Susac syndrome (SS) (retinocochleocerebral vasculopathy).

METHODS

  A retrospective review was performed of all patients presenting with SS at the Mayo Clinic in Rochester, Minnesota, USA (1 January 1998-1 October 2011).

RESULTS

  There were 29 cases of SS (24 women, mean age at presentation, 35 years; range, 19-65; full triad of brain, eye, and ear involvement, n = 16; mean follow-up time, 29 months). Thirty CSF analyses were performed in 27 cases (mean protein 130 mg/dl, range 35-268; mean cell count 14, range 1-86). MRI of the brain showed corpus callosal involvement (79%), T2-weighted hyperintensities (93%), and gadolinium enhancement (50%). Average lowest modified Rankin Scale score was 2.5 (median 2, range 0-5). Most patients (93%) received immunosuppressive treatment, with a mean time to treatment of 2 months following symptomatic onset. Treatments included intravenous methylprednisolone or dexamethasone (n = 23), oral corticosteroids (n = 24), plasma exchange (PLEX) (n = 9), intravenous immunoglobulin (IVIg) (n = 15), cyclophosphamide (n = 6), mycophenolate mofetil (n = 5), azathioprine (n = 2), and rituximab (n = 1). Most patients also received an antiplatelet agent (n = 21). Improvement or stabilization was noted in eight of 11 cases treated with IVIg in the acute period (three experienced at least partial deterioration) and eight of nine cases of PLEX treatment (one lost to follow up).

CONCLUSIONS

  Susac syndrome may be severe, disabling, and protracted in some patients. PLEX may be an adjunct or alternative therapy for patients who do not experience symptomatic improvement following steroid treatment.

Progressive multifocal leukoencephalopathy in transplant recipients

OBJECTIVE

Transplant recipients are at risk of developing progressive multifocal leukoencephalopathy (PML), a rare demyelinating disorder caused by oligodendrocyte destruction by JC virus.

METHODS

Reports of PML following transplantation were found using PubMed Entrez (1958-July 2010). A multicenter, retrospective cohort study also identified all cases of PML among transplant recipients diagnosed at Mayo Clinic, Johns Hopkins University, Washington University, and Amsterdam Academic Medical Center. At 1 institution, the incidence of posttransplantation PML was calculated.

RESULTS

A total of 69 cases (44 solid organ, 25 bone marrow) of posttransplantation PML were found including 15 from the 4 medical centers and another 54 from the literature. The median time to development of first symptoms of PML following transplantation was longer in solid organ vs bone marrow recipients (27 vs 11 months, p = 0.0005, range of <1 to >240). Median survival following symptom onset was 6.4 months in solid organ vs 19.5 months in bone marrow recipients (p = 0.068). Case fatality was 84% (95% confidence interval [CI], 70.3-92.4%) and survival beyond 1 year was 55.7% (95% CI, 41.2-67.2%). The incidence of PML among heart and/or lung transplant recipients at 1 institution was 1.24 per 1,000 posttransplantation person-years (95% CI, 0.25-3.61). No clear association was found with any 1 immunosuppressant agent. No treatment provided demonstrable therapeutic benefit.

INTERPRETATION

The risk of PML exists throughout the posttransplantation period. Bone marrow recipients survive longer than solid organ recipients but may have a lower median time to first symptoms of PML. Posttransplantation PML has a higher case fatality and may have a higher incidence than reported in human immunodeficiency virus (HIV) patients on highly-active antiretroviral therapy (HAART) or multiple sclerosis patients treated with natalizumab.

Cervicomedullary injury after pneumococcal meningitis with brain edema

OBJECTIVES

To demonstrate a rare but potential mechanism of quadriplegia in a patient with fulminant pneumococcal meningitis complicated by severe intracranial hypertension.

DESIGN

Case report.

SETTING

Intensive care unit.

PATIENT

A 21-year-old man who presented with 3 days of headache, combativeness, and fever.

INTERVENTION

Antibiotics and steroids were initiated after lumbar puncture yielded purulent cerebrospinal fluid and streptococcus pneumoniae.

RESULTS

The patient's course was complicated by severe cerebral edema necessitating intracranial pressure monitoring and intracranial pressure-targeted therapy. Within 5 days he developed quadriplegia and areflexia. Brain and cervical spine magnetic resonance imaging revealed patchy areas of T2 signal hyperintensity with associated gadolinium enhancement in the superior cervical spinal cord, cerebellar tonsils, and medulla.

CONCLUSIONS

Quadriplegia secondary to tonsillar herniation in fulminant meningitis is rare but should be considered in patients with acute quadriparesis after treatment of increased intracranial pressure. Magnetic resonance imaging signal changes and gadolinium enhancement may be demonstrated. Significant improvement of cord symptoms can be expected.

Enamel defects and salivary methylmalonate in methylmalonic acidemia

INTRODUCTION AND OBJECTIVE

To characterize enamel defects in patients with methylmalonic acidemia (MMA) and cobalamin (cbl) metabolic disorders and to examine salivary methylmalonate levels in MMA.

SUBJECTS AND METHODS

Teeth from patients (n = 32) were evaluated for enamel defects and compared with age- and gender-matched controls (n = 55). Complementation class (mut, cblA, cblB and cblC) and serum methylmalonate levels were examined. Primary teeth from two patients were examined by light and scanning electron microscopy and salivary methylmalonate levels from two patients were analyzed.

RESULTS

Enamel defects were significantly more prevalent per tooth in the affected group than the control group, across complementation types (P < 0.0001). The mut MMA subgroup had a significantly higher prevalence per individual of severe enamel defects than controls (P = 0.021), and those with enamel defects exhibited higher serum methylmalonate levels than those without (P = 0.017). Salivary methylmalonate levels were extremely elevated and were significantly higher than controls (P = 0.002). Primary teeth were free of enamel defects except for two cblC patients who exhibited severe enamel hypoplasia. One primary tooth from a cblC patient manifested markedly altered crystal microstructure.

CONCLUSION

Enamel anomalies represent a phenotypic manifestation of MMA and cbl metabolic disorders. These findings suggest an association between enamel developmental pathology and disordered metabolism.

Approach to a person recently diagnosed with diabetes

The physician who sees a newly diagnosed patient with diabetes can adequately fulfill his professional responsibilities by following a systematic approach to clinical diagnosis, investigations, appropriate treatment planning and involvement of the patient in is or her treatment through self-management education. Correct steps taken in the crucial initial period set the pace for optimum future management of this chronic disease.

Raman and AFM studies of swift heavy ion irradiated InGaAs/GaAs heterostructures

The effect of swift heavy ion (SHI) irradiation on InGaAs/GaAs heterostructures is studied using Raman spectroscopy and atomic force microscopy (AFM). The structures consist of molecular beam epitaxy (MBE) grown InGaAs layers on GaAs(001), having layer thicknesses of 12, 36, 60 and 96 nm. After irradiation, the GaAs type longitudinal optical (LO) mode blue shifted to higher frequency in thin samples and red shifted towards lower frequency in thick samples. These results are discussed invoking the penetration depth of the probe radiation (λ = 514.5 nm) in InGaAs. Deconvoluting the Raman spectra of thin samples indicates a compressive strain developed in the substrate, close to the interface upon irradiation. This modification and diffusion of indium across the interface results in an increase of strain and reduction of the defect densities in the InGaAs layer. The variations in FWHM of the Raman modes are discussed in detail. The surface morphology of these heterostructures has been studied by AFM before and after SHI irradiation. These studies, combined with Raman results, help to identify different relaxation regimes.

Sevoflurane for trans-sternal thymectomy in myasthenia gravis

Myasthenic gravis (MG) is an autoimmune disease associated with acetylcholine receptor deficiency. Patients with MG exhibit increased sensitivity to non-depolarising muscle relaxants. In an attempt to avoid neuromuscular blockers, we used sevoflurane in two myasthenic patients undergoing trans-sternal thymectomy. Inhalation of 8% sevoflurane in oxygen using vital capacity technique produced rapid, pleasant and smooth induction and provided good tracheal intubating conditions. In both patients anaesthesia was maintained with 1.5-2% end-tidal concentration of sevoflurane and nitrous oxide in oxygen without adjunctive neuromuscular blocking agents. There were minimal changes in cardiovascular variables and recovery was faster. It is suggested that sevoflurane may be the main anaesthetic for both induction and maintenance in myasthenic patients undergoing trans-sternal thymectomy.

Growth hormone therapy

Growth hormone therapy with rhGH (recombinant human growth hormone) has been recommended for treatment of GH deficient short stature in children, repeated hypoglycemias in infancy and early childhood due to GH deficiency, short stature accompanying chronic renal failure prior to renal transplantation and Turner's syndrome. It is now increasingly recommended to adults with GH deficiency following pituitary tumour surgery or irradiation or idiopathic hypopituitarism. There are other indications for its use where evidence for protein catabolism is very strong such as burns injury. The end points of GH therapy in children include achievement of desirable adult height or a growth rate velocity of < 2.5 cm/year. In adults GH deficiency, GH therapy is intended for improvement of general well being, body composition and metabolic markers of GH function.

Temple Ecology and Cognitive Development: A Report from South India

The impact of growing up in the vicinity of Hindu temples on cognitive development was studied in the southern part of India. Enrolled in Grades 1 and 4, the participating children (N-281) were drawn from three kinds of ecology, i.e., families intimately associated with temple, families that are religious but not so intimately associated with temple, and families in non-temple areas, using a cross-sectional design. NCERT School Readiness Scale and Das-Naglieri Cognitive Assessment System were used to assess their cognitive development. Children associated with temples emerged to be more cognitively competent than other two groups of children on both points of schooling. Sex differences and their interaction with ecology were not significant for most of the measures. Results point to the role of temple institutions in shaping development of children byproviding rich and variegated ecology.

Drug induced endocrine problems

Drug induced effects on the various endocrine and metabolic processes constitute a very common differential diagnostic possibility in investigating endocrine disorders. Knowledge of drug-effect is of paramount importance to avoid unnecessary and expensive investigations and treatment. Since most of the effects are type A effects and hence predictable, reduction of dose or modification of therapy is sufficient to reverse the adverse effects.

A preliminary standard for 'suradarulepa churna'- an ayurvedic preparation

SURADARU LEPA CHURNA'-A Compound drug formulation in Ayurvedic system of medicine was analysed. The proximate chemical analysis, the microscopic method of identifying their ingredients, flourescese study and thin layer chromatographic studies of the drug have been reported in this paper.

Nagakesara - a comparative pharmacognosy

Dried floral buds of Mesua ferrea Linn, dried fruits of Dillenia pentagyna Roxb and dried fruiting inflorescence of Cinnamomum wightii Meissn are used as Nagakesara in different regions of India. This elaborate study presents to the pharmacognosy of these three different drugs of Nagakesara.

STANDARDISATION OF "HAB - E - BUKHAR" (Unani Medicine)

'HAB-E-BUKHAR' - a compound drug formulation in Unani System of medicine has been analysed. The microscopic method of identification of few of its ingredients (Sath-e-gulu, Thabasheer); Quantitative analysis of Quinine sulphate, other physio-chemical contents and the T.L.C. of the drug have also been reported here.

Standardisation of dikamali

The gum Kidamali is an important oleoresin drug in the Indian System of Medicine. The market sample of Madras Crude drug trade has been identified as the gums of Gardenia gummifera Linn. f. of Rubiaceae. The morphology, microscopical structure of the source material, the fluorescence analysis and the chemical studies including thin layer chromatography of the drug are reported.

Kattu sirakam - its pharmacognosy

Kattusirakam or Vanajira is an important fruit drug in Siddha and Ayurveda systems of Medicine. The market sample of Madras has been identified in our laboratory as the fruits, commonly known as seeds of Centratherum anthelminticum (Willd) Kuntz. (Syn. Veronia anthelmintica Willd) of the family Compositate. The morphology, anatomy, fluorescence analysis and chemical characters of the drug are dealt with here.

A preliminary standard for nilaavarai curnam - a siddha preparation

Nilavarai Curnam, a compound drug formulation in Siddha System of Medicine was analysed. The Microscopic methods of identifying their ingredients, Chemical analysis, Fluorescence, and Thin Layer Chromatographic studies of the drug have been reported here.

Miskitaramashia

Miskitaramashia is a special single drug in Unani system of medicine and it has been identified as Lallemantia royleana (Wall) Benth. Of the family Labiacae. Its pharmacognostical characters hava also been reported here.

The pharmacognosy of nattu atividayam - the corms of cryptocoryne spiralis fisch

The pharmacognosy of Nattu Attivdayam the corms of Cryptocoryne spiralis Fisch - its macroscopical, microscopical and chemical studies - is reported.