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Formation of the acrosome during spermiogenesis is an essential process for creating fertilization-competent sperm. Of the numerous aspects required for acrosome biogenesis, adherence of the acrosomal outer membrane to the nuclear surface is mediated by the subacrosomal perinuclear theca. However, the cellular dynamics and congruent functions pertaining to these acrosomal anchoring factors are not well understood despite many of them being implicated as potential causes for human male infertility. Actin-like 7A (ACTL7A) is one such factor for which deleterious polymorphisms have recently been shown to cause human male infertility. It is thought that acrosomal attachment is coordinated by cytoskeletal associations between the acrosome and nucleus via the acroplaxome. To further illuminate the mechanistic underpinnings of ACTL7A for essential acrosome associations, in this study, we investigated its dynamic localization in the developing germline, molecular associations with other cytoskeletal components, and the cellular consequences of ablation. Our intracellular localization data show ACTL7A to be dynamically present within the nucleus and subacrosomal space and later associated with postacrosomal regions of developing spermatids. Through the generation of an Actl7a knock-out mouse model, we consistently observed disruption of acrosomal biogenesis with abnormal migration of the acrosomal granule and peeling acrosomes during spermatid elongation. Significantly, we found a complete loss of subacrosomal filamentous actin (F-actin) structures in knock-out spermatids suggesting a regulatory role for subacrosomal F-actin. Considering our reported data together with existing literature, we propose a mechanistic model explaining the essential role of ACTL7A for acroplaxome-associated F-actin, acrosomal attachment integrity, and male fertility.

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The rise in environmental pollutant levels in recent years is mostly attributable to anthropogenic activities such as industrial, agricultural and other activities. Additionally, these activities may produce excessive levels of dangerous toxicants such as heavy metals, organic pollutants including pesticide and herbicide chemicals, and sewage discharges from residential and commercial sources. With a focus on environmentally friendly, sustainable technology, new technologies such as combined process of nanotechnology and bioremediation are urgently needed to accelerate the cost-effective remediation process to alleviate toxic contaminants than the conventional remediation methods. Numerous studies have shown that nanoparticles possess special qualities including improved catalysis and adsorption as well as increased reactivity. Currently, microorganisms and their extracts are being used as promising, environmentally friendly catalysts for engineered nanomaterial. In the long term, this combination of both technologies called nano-bioremediation may significantly alter the field of environmental remediation since it is more intelligent, safe, environmentally friendly, economical and green. This review provides an overview of soil and water remediation techniques as well as the use of nano-bioremediation, which is made from various living organisms. Additionally, current developments related to the mechanism, model and kinetic studies for remediation of agricultural contaminants have been discussed.

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Peanut shell biomass was selected and utilized to produce biochar through pyrolysis under N2 atmosphere at 923 K. After studying various effects of experimental parameters and by statistical modeling and optimization by RSM using Box-Benken design, optimized conditions of pH 2.0 ± 0.1, temperature 303 K, and adsorbent dose used of 2.5 g L-1 were obtained giving almost 99.99% removal for Cr(VI) from the solution. FESEM, FTIR, XRD, XPS, EDX, elemental mapping, and pHzpc were used for the evaluation of the surface characteristics of peanut shell biochar (PSB). Studies revealed C-O, C-H, CO, and O-H functional groups' presence with the help of FTIR, majorly in control of adsorption mechanism and the EDX confirmed the presence of Cr(VI) onto peanut shell biochar (PSB). Further adsorption mechanism for Cr(VI) adsorption followed the pseudo-second-order rate with adsorption capacity of 29.38 mg g-1 given by the Langmuir isotherm. The thermodynamic study confirmed the exothermic and spontaneous nature of the process for Cr(VI) adsorption onto PSB. The adsorption mechanism showed electrostatic attraction, reduction, and complexation mainly responsible for Cr(VI) adsorption by PSB. Thus, PSB effectively removes Cr(VI) is confirmed by the present study.

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A study aims to determine comparative pathology of induced anchylostomiasis was conducted in murine model. L3 larvae of Ancylostoma caninum were given at the rate of 200 larvae per rat orally and 1000 per rat through per cutaneous route in both healthy and diabetic groups as per the design of the experiment. Blood samples were collected on day 15, 30 and 45 for haemato-biochemical investigations. Decrease in Hb, PCV, TEC was observed in all groups as compared to healthy control. Leukocytosis with neutrophilia and eosinophilia was also recorded. An increase in glucose, cholesterol, ALT and AST was recorded in diabetic groups as compared to their counterparts. BUN and creatinine was elevated in all infected group. Similarly total protein and albumin gradually declines (after initial increase) in all the groups. Most of the parameters remain unaffected in group V as compared to control. It was concluded that the pathology of induced anchylostomiasis in murine model is more sever in diabetic group as evident by the significantly altered haemato-biochemical parameters when compare to their counterparts. This may be due to damage caused by non treated diabetes to different body system in addition to the anchylostomiasis.

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OBJECTIVE: Low fat duck meat sausages were prepared by replacing the fat in the formulations with soy protein isolate (SPI) and inulin to find the best formulation having superior shelflife without affecting its quality attributes. METHODS: Four sausage mix formulations were prepared viz.control (0% SPI and inulin), T1 (2.5% inulin), T2 (2.5% SPI), and T3 (2.5% SPI+2.5% inulin) replacing duck fat as per the recipe. Five batches of duck meat sausages of each formulation were prepared, and the final products were evaluated for physico-chemical, organoleptic, and microbiological qualities. RESULTS: The % moisture and crude protein content of the sausages revealed an increasing trend (p<0.01) from control to the treated formulations, while the % total ash contents were found to be non-significant (p>0.05). On the contrary, the per cent ether extract decreased significantly (p<0.01) from the control to the treated groups. In terms of calorie value, control samples exhibited the highest values with a significant (p<0.01) regression from control to treated formulation, respectively. The colour profile study (L, a*, b*) of the formulations were found to be non-significant. Texture profile study in terms of springiness, cohesiveness, chewiness, and resilience revealed no significant difference in all the treatment groups except the hardness scores, which revealed a significantly (p<0.01) increasing trend from control to the treated formulations. The total viable count showed a significant decrease in the treated groups. However, there was a significant increase in the bacterial load during the storage till day 15th. The total viable psychrophilic bacterial count showed a significant (p<0.01) increase in bacterial load from day 5th to 15th day of storage. Colititre counts were negative for all the formulations until the 15th day of storage. CONCLUSION: The present study results may conclude that duck meat sausages could be prepared satisfactorily by replacing duck fat with SPI and inulin at the rate of 2.5% of each with superior quality attributes.

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Background Primary teeth emergence is an important milestone in children and timing of emergence varies among populations. Objective To determine the emergence time and sequence of primary teeth in a sample of Nepalese children visiting Dhulikhel Hospital. Method A descriptive cross-sectional study was conducted in children of 5 months to 4 years visiting Dhulikhel Hospital. The emergence of incisal tip to incisal margin for incisors and canines, cusp tip to occlusal margin of molars visible were recorded along with age in months and gender. Descriptive statistics was done to calculate the mean age of emergence of each tooth with standard deviation. Unpaired t-test was used to assess the difference between the mean age of emergence of teeth between right and left sides and between boys and girls. Result The first teeth to emerge was mandibular central incisor at the age of 9.37 ± 1.42 months and the last one was maxillary second molar at the age of 32.91 ± 6.39 months. There was no significant difference in the mean emergence time between the maxillary and mandibular jaws, between right and left sides of jaws and between boys and girls except for primary maxillary right central incisor and mandibular right second molar which was found to be emerged early in girls. Conclusion The emergence time and sequence of primary teeth observed in the present study can be used as a baseline data for the children of Kavre district.

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Background Early childhood caries (ECC) in preschool children debilitate their quality of life affecting oral function, appearance and social well-being. A tool for measuring oral health-related quality of life for preschoolers may help in making clinical decisions and assist policy makers in planning and management of health programs in the country. Objective To translate oral health-related early childhood quality of life (OH-ECQoL) tool into Nepali language and test its validity and reliability. Method OH-ECQoL was translated into Nepali language by two Nepalese professional translators which was back translated by professional English translator. This was sent to three independent advisors to see the appropriateness of translation. Pilot testing was done in 20 parents and questionnaire was finalized after needed corrections. Final version was introduced to the 118 parents of children aged 24- 71 months. Caries status was recorded for all children participating in the study. Concurrent, construct, discriminant validity and internal consistency reliability, test -retest reliability were evaluated. Result OH-ECQoL scores and perception of parents for general and oral health of their children was significant (at 0.01 level). There was significant difference in OH-ECQoL scores between no ECC and severe ECC groups and moderate and severe ECC groups (at 0.05 level). There was also a significant correlation between child impact section and family impact section (at 0.01 level). Cronbach's alpha was 0.891 demonstrating good internal consistency. Intra class coefficient was 0.963 suggesting excellent testretest reliability. Ninety-one (77.1%) children had severe ECC and 40(33.9%) parents were from upper middle class. Conclusion The Nepali version of OH-ECQoL is a valid and reliable tool for assessing the oral health-related early childhood quality of life in children of Nepal.

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The N-methyl-d-aspartate receptors (NMDARs) are ionotropic ligand gated channels that are highly permeable to calcium ions. In insects, NMDARs are associated with glutamatergic neurotransmission governing diverse physiological and biological processes like vitellogenesis and ovarian development. Therefore, NMDAR may act as attractive target for insect pest control. In present study, we performed structural and functional characterization of NMDARs in Bemisia tabaci, a highly invasive crop pest and potent virus vector. We identified that NMDAR consists of three subunits each encoded by single gene in whiteflies which are highly conserved among different insect orders. Expression analysis suggests that subunit 1 (BtNR1) and subunit 2 (BtNR2) are the main functional units. External supplementation of NMDAR ligand or BtNRs silencing was lethal to insects, which suggested that NMDAR function is highly balanced in whiteflies.

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Myeloid sarcomas (MS) are a rare manifestation of myeloid malignancies and can often be misdiagnosed, leading to a delay in treatment. The objective of this clinical case is to highlight the challenges of the clinical presentation and to emphasize the importance of this manifestation ensuring timely diagnosis and therapy. Here, we present a 43-year-old man who was diagnosed with acute myeloblastic leukemia (AML) after being evaluated for unintentional weight loss, subcutaneous nodules, thrombocytopenia, and anemia. The patient underwent chemotherapy with complete remission and presented 4 months later with dysphagia and cranial nerve palsies. Appropriate imaging and biopsy led to a diagnosis of myeloid sarcoma, and a decision was made to begin reinduction chemotherapy for AML achieving a second complete remission although his neurological deficits did not improve. Our case illustrates the protean presentation of myeloid sarcomas; clinicians should have a high suspicion for MS and remain vigilant when unexplained signs and symptoms arise in the background of a myeloid malignancy although challenges still remain when presentation is de novo. Advancements in understanding the pathophysiology of MS have been performed but remain not completely understood. High clinical suspicion, appropriate imaging, biopsy techniques, and expertise are paramount for timely diagnosis and treatment.

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The thermo-chemical characterization (proximate and ultimate analyses and higher heating value) of banana trunk biomass waste has been carried out. The thermo-gravimetric and differential scanning calorimetric (DSC) investigations have been made at heating rates of 10, 15, 20 and 25 °C/min. The TGA data have been used to carry out kinetic analysis and evaluate the kinetic and thermodynamic parameters using iso-conversional models. The values of activation energy increase with conversion (α) irrespective of the iso-conversional model used. The average values of activation energies (Eα) are found to be 386.21, 355.43, 385.77, 355.01, 379.67, and 292.78 kJ/mol for Flynn-Wall-Ozawa (FWO), Starink, Kissinger-Akahira-Sunose (KAS), Tang, Vyzovkin and Vyzovkin AIC model, respectively. The average values of change in enthalpy, Gibbs free energy, and entropy have been calculated. The reaction mechanisms of pyrolysis have been predicted using Criado's method.

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The thermal degradation of paper mill waste (PMW) has been investigated in presence and absence of Montmorillonite clay in the temperature range of ambient to 1000 °C and at the heating rates of 20 °C/min, 25 °C/min and 30 °C/min. Proximate and ultimate analyses and evaluation of calorific value (HHV) of PMW have been carried out using standard protocols. The thermo-gravimetric analysis (TGA) and differential thermogravimetric (DTG) data obtained under both situations have been used to evaluate the kinetic and thermodynamic parameters and elucidate the reaction mechanism. The clay has also been characterized using TGA/DTG analysis, Fourier Transform Infra-Red (FTIR) spectroscopic analysis and X-ray diffraction (XRD), Energy dispersive spectroscopy (EDS), and scanning electron microscopic (SEM) techniques. The activation energy, pre-exponential factor and thermodynamic parameters have been evaluated using the model-free iso-conversional method of Flynn-Wall-Ozawa (FWO) and Vyazovkin and the distributed activation energy model (DAEM). The Montmorillonite clay has influenced the degradation process appreciably through its catalytic action.

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The Performance of rolling element bearings has a significant influence on reliability and safety in the various engineering fields. While heading toward the condition evaluation of rolling element bearings, the higher dimensionality of feature space became a crucial concern. Thus, to have a check on the hurdles, this paper proposes a novel approach of bearing condition assessment utilizing Local mean decomposition (LMD) and spectral clustering (SC). Spectral Clustering (SC) is an influential tool, which heals the curse of dimensionality and facilitates the model by imparting a systematized structure. SC focuses more on connectivity rather than geometrical vicinity; moreover, the provision of a similarity matrix makes SC more reliable and increases its performance. To enrich the efficiency of SC, a novel decision criterion, PI (Parting Index) aiming the optimal number of clusters based on a new similarity indicator and disorder indicator coined as Synergic Association Index (SAI) and Separation Index (SI) respectively, has been proposed. The work aims to achieve better performance degradation assessment (PDA) by the application of the new SC-PI approach with the following steps; the first step is the decomposition of vibration signal into product functions (PFs) utilizing LMD; the second step involves the extraction of proper fault features; third, the extracted features are classified with the SC-PI method; finally the feature or attribute vectors are endowed to trained model and confidence value (CV) is calculated. The proposed method is validated on two datasets of different fault types. The results so obtained indicates that the SC-PI method easily differentiates the various stages when compared to different assessment techniques i.e. time-domain features, self-organizing map (SOM), k-medoids and Gaussian mixture model (GMM).

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Somatic embryogenesis receptor kinases (SERKs) play a significant role in morphogenesis, stress/defense and signal transduction. In the present study, we have identified two SERK and 11 SERK-like (SERL) genes in Phalaenopsis equestris, two SERK and 11 SERL genes in Dendrobium catenatum, and one SERK and eight SERL genes in Apostasia shenzhenica genome. Characterization of the SERK proteins revealed the presence of a signal peptide, a leucine zipper, five leucine-rich repeats (LRRs), a serine proline proline (SPP) motif, a transmembrane region, a kinase domain, and a C-terminus. Most of the SERK/SERL proteins were characterized with similar physicochemical properties. The presence of transmembrane region predicted their membranous localization. Tertiary structure prediction of all the five identified SERK proteins had sequence identity with BAK1 protein of Arabidopsis thaliana. Generally, all the SERK/SERL genes shared similar gene architecture and intron phasing. Gene ontology analysis indicated the role of SERKs in receptor and ATP binding, signal transduction, and protein phosphorylation. Phylogenetic analysis revealed the clustering of SERKs and SERLs in distinct clades. Expression of SERKs in reproductive tissues like floral bud, floral stalk, whole flower and pollen was reported to be higher than their expression in vegetative tissues with an exception of PeSERK1 and DcSERK1 which showed higher expression in leaves and roots, respectively. Likewise, a higher expression of AsSERK1 was observed in tubers. However, lower expression of SERLs was observed in majority of tissues studied irrespective of their vegetative or reproductive origin. This work paves way for future studies involving functional characterization of SERK/SERLs and their potential role in embryogenesis/organogenesis as an aid to regeneration and multiplication of endangered orchids.

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Pyrolysis of sugarcane (Saccharum officinarum L) leaves (SCL) has been investigated using DTA/TGA and DSC techniques. Proximate and ultimate analyses and calorific value measurement have been carried out using standard protocols. The sugar cane leaves contain 44% cellulose, 22% hemicellulose and 17% lignin. The pyrolysis have been carried out at six heating rates varying from 5 to 40 °C/min. Analysis of the pyrolysis results has been carried using iso-conversional model free methods as well as multiple linear regression method. For the fractional conversion range of 0.05-0.95, the average apparent activation energy values evaluated from iso-conversional methods have ranged from 214.9 to 239.6 kJ/mol where as in the case of multiple linear regression analysis it has ranged from 25.06 to 57.23 kJ/mol. The multi-step reaction mechanism has been investigated using the Criado method. The results of this study are useful for the design of large scale biomass thermal conversion process.

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Macrophages are first-line responders against microbes. The success of Mycobacterium tuberculosis (Mtb) rests upon its ability to convert these antimicrobial cells into a permissive cellular niche. This is a remarkable accomplishment, as the antimicrobial arsenal of macrophages is extensive. Normally bacteria are delivered to an acidic, degradative lysosome through one of several trafficking pathways, including LC3-associated phagocytosis (LAP) and autophagy. Once phagocytozed, the bacilli are subjected to reactive oxygen and nitrogen species, and they induce the expression of proinflammatory cytokines, which serve to augment host responses. However, Mtb hijacks these host defense mechanisms, manipulating host cellular trafficking, innate immune responses, and cell death pathways to its benefit. The complex series of measures and countermeasures between host and pathogen ultimately determines the outcome of infection. In this review, we focus on the diverse effectors that Mtb uses in its multipronged effort to subvert the innate immune responses of macrophages. We highlight recent advances in understanding the molecular interface of the Mtb-macrophage interaction.

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Background Integrated curriculum enhances students' learning and the retention of knowledge. At Patan Academy of Health Sciences, integrated organ system based curriculum is used with Problem Based Learning as the principle teaching learning method to foster students' learning. In addition, other approaches of integration were under taken such as integrated assessment; logical arrangement teaching learning methods (lectures and practicals); joint effort of faculty in curriculum planning and delivery; conducive environment to foster hidden curriculum. This study describes the perception of faculty and students on integration characteristics of Basic Science curriculum. Objective To measure the integration characteristics of Basic Science Curriculum. Method Tool was developed to measure integration characteristics of Basic Science Curriculum and ensure whether such planned integration has been achieved. Mixed method was used to measure the perception of the integration characteristics i) quantitatively by questionnaire survey to faculty and students ii) qualitatively by in-depth interview of students. Result Both faculty and students perceived that all the blocks in Basic Science was well integrated in the quantitative questionnaire survey. But, in the in-depth interview, students perceived integration of curriculum in organ system blocks were better integrated compared to Principle of Human Biology blocks where fundamentals of basic science disciplines were delivered. Students reflected that Problem Based Learning not only integrated Basic Science disciplines but also with clinical sciences and the social context. But, students perceived that Community Health Sciences curriculum was not so well integrated with Basic Science subjects. Conclusion Overall, this study showed that planned integration in Basic Science curriculum was successfully executed during curriculum implementation.

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Growths of Lyngbya limnetica and Oscillatoria obscura were investigated at varying pH, light intensity, temperature, and trace element concentration with a view to optimize these parameters for obtaining the maximum carbohydrate content. The maximum growth for both strains was obtained at pH 9.0 and temperature 20 ± 3 °C using a light intensity of 68.0 µmol m-2 s-1 with continuous shaking. Growth under the nitrogen starvation condition affected the carbohydrate content more compared to the phosphorus starvation, and maximum concentrations were found as 0.660 and 0.621 g/g of dry biomass for L. limnetica and O. obscura, respectively. Under the optimized nitrogen-rich conditions, the specific growth rates for the two strains were found to be 0.187 and 0.215 day-1, respectively. The two-stage growth studies under nitrogen-rich (stage I) followed by nitrogen starvation (stage II) conditions were performed, and maximum biomass and carbohydrate productivity were found as 0.088 and 0.423 g L-1 day-1 for L. limnetica. This is the first ever attempt to evaluate and optimize various parameters affecting the growth of cyanobacterial biomass of L. limnetica and O. obscura as well as their carbohydrate contents.

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BACKGROUND: Patan Academy of Health Sciences (PAHS) aims to produce physicians who would be able and willing to serve in the rural areas. Recognizing the critical importance of student selection strategy, among others, in achieving the program goals, it has adopted an innovative scheme for selecting medical students. This paper describes PAHS medical student selection scheme that favors enrollment of deserving applicants from rural and disadvantaged groups so as to help improve distribution of physicians in rural Nepal. METHODS: A student admission committee comprising a group of medical educators finalized a three-step student selection scheme linked with scholarships after reviewing relevant literatures and consultative meetings with experts within and outside Nepal. The committee did local validation of Personal Quality Assessment (PQA) that tested cognitive ability and personality traits, Admission OSPE (Objective Structured Performance Examination) that assessed non-cognitive attributes of applicants. It also provided preferential credits to applicants' socio-economic characteristics to favor the enrollment of deserving applicants from rural and disadvantaged groups through Social Inclusion Matrix (SIM). Three different categories of scholarship schemes namely Partial, Collaborative and Full were devised with Partial providing 50% and other two categories each providing 100% coverage of tuition fee. RESULTS: PAHS student selection scheme succeeded in enrolling more than half of its students from rural areas of Nepal, including about 10% of the students from that of the most backward region of the country. About one third of students were female and about the same were from public and community school. Sixty percent of students receive different categories of scholarships. CONCLUSIONS: Limited findings indicate the success of the selection scheme in enrolling high proportion of applicants from rural and disadvantageous groups and enable them to pursue study by providing scholarships.

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The main objective of this study was to evaluate the performance of wood charcoal as biofilter media under transient and high loading condition. Biofiltration of xylene was investigated for 150days in a laboratory scale unit packed with wood charcoal and inoculated with mixed microbial culture at the xylene loading rates ranged from 12 to 553gm-3h-1. The kinetic analysis of the xylene revealed absence of substrate inhibition and possibility of achieving higher elimination under optimum condition. The pH, temperature, pressure drop and CO2 production rate were regularly monitored during the experiments. Throughout experimental period, the removal efficiency (RE) was found to be in the range of 65-98.7% and the maximum elimination capacity (EC) was 405.7gm-3h-1. Molecular characterization results show Bacillus sp. as dominating microbial group in the biofilm.

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Background Earlychildhood caries (ECC) is a multifactorial disease. Maternal factors and family income has major influence on the caries status of children. Objective To assess the relationship of maternal factors and family income with early childhood caries among children attending Pediatric Dentistry department of Dhulikhel Hospital. Method A cross sectional study was conducted among 239 children of age 3 to 6 years attending Pediatric Dentistry department of Dhulikhel Hospital, Kavre, Nepal. Age of child, mother's occupational status,educational level and family income were recorded. Oral examination of child was done to record decayed, missing, filled teeth (dmft). Descriptive analysis was done to observe the caries experience. Chi - square test was used to assess the relationship of caries experience with occupational status, education of mother and family income. Result The mean decayed, missing, filled teeth of the children was7.04±4.10. There was no significant relationship of early childhood caries with occupational status of mother (p=0.675), education of mother (p=0.140) and family income (p=0.158). Conclusion There was no relationship of maternal factors and family income with early childhood caries when surveyed among the children visiting Pediatric Dentistry department of Dhulikhel hospital.

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