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BackgroundThere is growing interest and investment in electronic immunization registries (EIRs) in low- and middle-income countries. EIRs provide ready access to patient- and aggregate-level service delivery data that can be used to improve patient care, identify spatiotemporal trends in vaccination coverage and dropout, inform resource allocation and program operations, and target quality improvement measures. The Government of Tanzania introduced the Tanzania Immunization Registry (TImR) in 2017, and the system has since been rolled out in 3736 facilities in 15 regions. ObjectiveThe aims of this study are to conceptualize the additional ways in which EIRs can add value to immunization programs (beyond measuring vaccine coverage) and assess the potential value-add using EIR data from Tanzania as a case study. MethodsThis study comprised 2 sequential phases. First, a comprehensive list of ways EIRs can potentially add value to immunization programs was developed through stakeholder interviews. Second, the added value was evaluated using descriptive and regression analyses of TImR data for a prioritized subset of program needs. ResultsThe analysis areas prioritized through stakeholder interviews were population movement, missed opportunities for vaccination (MOVs), continuum of care, and continuous quality improvement. The included TImR data comprised 958,870 visits for 559,542 patients from 2359 health facilities. Our analyses revealed that few patients sought care outside their assigned facility (44,733/810,568, 5.52% of applicable visits); however, this varied by region; facility urbanicity, type, ownership, patient volume, and duration of TImR system use; density of facilities in the immediate area; and patient age. Analyses further showed that MOVs were highest among children aged

The flow of potassium ions through cell membranes plays a crucial role in facilitating various cell processes such as hormone secretion, epithelial function, maintenance of electrochemical gradients, and electrical impulse formation. Potassium ion inhibitors are considered promising alternatives in treating cancer, muscle weakness, renal dysfunction, endocrine disorders, impaired cellular function, and cardiac arrhythmia. Thus, it becomes essential to identify and understand potassium ion inhibitors in order to regulate the ion flow across ion channels. In this study, we created a meta-model, POSSUM, for the identification of potassium ion inhibitors. Two distinct datasets were used for training, testing, and evaluation of the meta-model. We employed seven feature descriptors and five distinctive classifiers to construct 35 baseline models. We used the mean Gini index score to select the optimal base models and classifiers. The POSSUM method was trained on the optimal probabilistic feature vectors. The proposed optimal model, POSSUM, outperforms the baseline models and the existing methods on both datasets. We anticipate POSSUM will be a very useful tool and will be essential in the process of finding and screening possible potassium ion inhibitors., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

We hereby report the development of a novel electrochemical method to degrade perfluorooctanoic acid (C 7 F 15 COOH, PFOA). At the center of the approach are bimetallic Pd-Ru nano-catalyst materials called IMPACT: Innovative (nano)Materials and Processes for Advanced Catalytic Technologies. IMPACT uses flavonoid-sequestered Pd-Ru, allowing the development of specialized electrodes with tunable properties to sequentially degrade PFOA in wastewater samples into a sustainable byproduct via an indirect electrochemical method. Electron transfers at RuO x H y species stabilize the Pd component of the nano-catalysts, enabling the degradation process via PFOA deprotonation, chain shortening, decarboxylation, hydrolysis, fluoride elimination, and CF 2 flake-off mechanism. IMPACT enabled the observation of redox peaks at -0.26 V and 0.56 V for the first time, with accompanying reduction peaks at -0.5V and 0.29 V, respectively. These redox peaks, which correlated with the concentrations of PFOA (20, 50, 100, 200, and 400. mg L -1 ), were verified and confirmed using electrochemical simulations. Control experiments did not show degradation of PFOA in the absence of Pd-Ru nano-catalyst. The degradation in wastewater was obtained within 3 h with an efficiency of 98.5%. The electrochemical degradation products of PFOA were identified using High-resolution desalting paper spray mass spectrometry (DPS-MS) and collision-induced dissociation (CID) analysis. The results yielded C 2 F 5 COOH, C 3 F 7 COOH, and C 6 F 13 OH with dissociation losses of CF 2 O or CO 2 . IMPACT introduces a novel nano-catalyst with high efficiency and a reliable capability that defluorinates strong C-F bonds that are components of recalcitrant organics in myriad environmental matrices., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Advances in attosecond spectroscopy have enabled tracing and controlling the electron motion dynamics in matter, although they have yielded insufficient information about the electron dynamic in the space domain. Hence, ultrafast electron and x-ray imaging tools have been developed to image the ultrafast dynamics of matter in real time and space. The cutting-edge temporal resolution of these imaging tools is on the order of a few tens to a hundred femtoseconds, limiting imaging to the atomic dynamics and leaving electron motion imaging out of reach. Here, we obtained the attosecond temporal resolution in the transmission electron microscope, which we coined "attomicroscopy." We demonstrated this resolution by the attosecond diffraction measurements of the field-driven electron dynamics in graphene. This attosecond imaging tool would provide more insights into electron motion and directly connect it to the structural dynamics of matter in real-time and space domains, opening the door for long-anticipated real-life attosecond science applications in quantum physics, chemistry, and biology.

High-affinity ligand peptides for ion channels are essential for controlling the flow of ions across the plasma membrane. These peptides are now being investigated as possible therapeutic possibilities for a variety of illnesses, including cancer and cardiovascular disease. So, the identification and interpretation of ligand peptide inhibitors to control ion flow across cells become pivotal for exploration. In this work, we developed an ensemble-based model, NaII-Pred, for the identification of sodium ion inhibitors. The ensemble model was trained, tested, and evaluated on three different datasets. The NaII-Pred method employs six different descriptors and a hybrid feature set in conjunction with five conventional machine learning classifiers to create 35 baseline models. Through an ensemble approach, the top five baseline models trained on the hybrid feature set were integrated to yield the final predictive model, NaII-Pred. Our proposed model, NaII-Pred, outperforms the baseline models and the current predictors on both datasets. We believe NaII-Pred will play a critical role in screening and identifying potential sodium ion inhibitors and will be an invaluable tool., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

In proper skin healing, inflammation will stop once the harmful microbes are removed. However, an excess and prolongation of inflammation can result in delayed healing. Thus, interventions that can limit the amount of inflammation can help promote wound healing. The use of olive oil in wound therapy has been of great interest. Herein, we will review studies that investigated the use of olive oil on diabetic foot ulcers, pressure ulcers, perineal ulcers, and chronic ulcers.

This study aims to comprehensively assess the presence of aflatoxins, pervasive fungal toxins, and heavy metals (lead, chromium, cadmium) in the local feed of fish and shrimp. Forty-eight samples of the fish and shrimp feed were collected from the Dhaka and Sathkhira districts of Bangladesh respectively. Aflatoxins (B1, B2, G1, G2) were analyzed by high-performance liquid chromatography (HPLC) with fluorescence detector, and atomic absorption spectrophotometry (AAS) was used for the heavy metal detection after sample digestion. The standard analytical methods of the Association of Official Analytical Chemists were followed for analyzing the proximate composition of the feed samples. The findings revealed the high toxic concentration of total aflatoxins particularly in fish feed (196.25 μg/kg). Concurrently, varying concentrations of heavy metals, including lead (Pb) and chromium (Cr), were detected, with the highest levels found in shrimp feed at 3.324 and 174.6 mg/kg, respectively. In comparison, highest contamination of cadmium (Cd) was found in fish feed at 0.398 mg/kg. The outcomes are growing concerns regarding the quality of locally sourced feed and emphasizing the need for prompt corrective actions. Otherwise, neglecting this concern may lead to the possibility of both fish and, ultimately, humans who consume them being vulnerable to the absorption and accumulation of these assessed toxic compounds., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

A study of the dead layer thickness and quenching factor of a plastic scintillator for use in ultracold neutron (UCN) experiments is described. Alpha spectroscopy was used to determine the thickness of a thin surface dead layer to be 630 ± 110 nm. The relative light outputs from the decay of 241Am and Compton scattering of electrons were used to extract Birks' law coefficient, yielding a kB value of 0.087 ± 0.003 mm/MeV, consistent with some previous reports for other polystyrene-based scintillators. The results from these measurements are incorporated into the simulation to show that an energy threshold of (∼9 keV) can be achieved for the UCNProBe experiment. This low threshold enables high beta particle detection efficiency and the indirect measurement of UCN. The ability to make the scintillator deuterated, accompanied by its relatively thin dead layer, gives rise to unique applications in a wide range of UCN experiments, where it can be used to trap UCN and detect charged particles in situ., (© 2024 Author(s). Published under an exclusive license by AIP Publishing.)

Traditional PFAS analysis by mass spectrometry (MS) is time-consuming, as laborious sample preparation (e.g., extraction and desalting) is necessary. Herein, we report fast detection of PFAS by paper spray (PS)-based MS techniques, which employs a triangular-shaped filter paper for sample loading and ionization (≤ 3 min per sample). In this study, PS-MS was first used for direct PFAS analysis of drinking water, tap water, and wastewater. Interestingly, food package paper materials can be directly cut and examined with PS-MS for possible PFAS contamination. For samples containing salt matrices which would suppress PFAS ion signal, desalting paper spray mass spectrometry (DPS-MS), was shown to be capable of rapidly desalting, ionizing and detecting PFAS species such as per-fluorooctanoic acid (PFOA) and per-fluorosulphonic acid (PFOS). The retention of PFAS on paper substrate while salts being washed away by water is likely due to hydrophilic interaction between the PFAS polar head (e.g., carboxylic acid, sulfonic acid) with the polar filter paper cellulose surface. The DPS-MS method is highly sensitive (limits of detection:1.2-4.5 ppt) and can be applicable for directly analyzing soil extract and soil samples. These results suggest the high potential of PS-MS and the related DPS-MS technique in real-world environmental analysis of PFAS., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Numerous putative glycosyltransferases (GTs) have been identified using bioinformatic approaches. However, demonstrating the activity of these GTs remains a challenge. Here, we describe the development of a rapid in vitro GT-array screening platform for activity of GTs. GT-arrays are generated by cell-free in vitro protein synthesis and binding using microplates precoated with a N-terminal Halo- or a C-terminal GST-tagged GT-encoding plasmid DNA and a capture antibody. These arrays are then used for screening of transferase activities and the reactions are monitored by a luminescence GLO assay. The products formed by these reactions can be analyzed directly from the microplates by mass spectrometry. Using this platform, a total of 280 assays were performed to screen 22 putative fucosyltransferases (FUTs) from family GT37 (seven from Arabidopsis and 15 from rice) for activity toward five acceptors: non-fucosylated tamarind xyloglucan (TXyG), arabinotriose (Ara 3 ), non-fucosylated rhamnogalacturonan I (RG-I), and RG-II from the mur1-1 Arabidopsis mutant, and the celery RG-II monomer lacking Arap and MeFuc of chain B and l-Gal of chain A. Our screen showed that AtFUT2, AtFUT5, and AtFUT10 have activity toward RG-I, while AtFUT8 was active on RG-II. Five rice OsFUTs have XyG-FUT activity and four rice OsFUTs have activity toward Ara 3 . None of the putative OsFUTs were active on the RG-I and RG-II. However, promiscuity toward acceptors was observed for several FUTs. These findings extend our knowledge of cell wall polysaccharide fucosylation in plants. We believe that in vitro GT-array platform provides a valuable tool for cell wall biochemistry and other research fields., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

The escalating global incidence of cancer poses significant health challenges, underscoring the need for innovative and more efficacious treatments. Cancer immunotherapy, a promising approach leveraging the body's immune system against cancer, emerges as a compelling solution. Consequently, the identification and characterization of tumor T-cell antigens (TTCAs) have become pivotal for exploration. In this manuscript, we introduce TTCA-IF, an integrative machine learning-based framework designed for TTCAs identification. TTCA-IF employs ten feature encoding types in conjunction with five conventional machine learning classifiers. To establish a robust foundation, these classifiers are trained, resulting in the creation of 150 baseline models. The outputs from these baseline models are then fed back into the five classifiers, generating their respective meta-models. Through an ensemble approach, the five meta-models are seamlessly integrated to yield the final predictive model, the TTCA-IF model. Our proposed model, TTCA-IF, surpasses both baseline models and existing predictors in performance. In a comparative analysis involving nine novel peptide sequences, TTCA-IF demonstrated exceptional accuracy by correctly identifying 8 out of 9 peptides as TTCAs. As a tool for screening and pinpointing potential TTCAs, we anticipate TTCA-IF to be invaluable in advancing cancer immunotherapy., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper, (Copyright © 2024. Published by Elsevier B.V.)

Background: The most commonly used therapy currently for inflammatory and autoimmune diseases is nonspecific anti-inflammatory drugs, which have various hazardous side effects. Recently, some anti-inflammatory peptides (AIPs) have been found to be a substitute therapy for inflammatory diseases like rheumatoid arthritis and Alzheimer's. Therefore, the identification of these AIPs is an emerging topic that is equally important., Methods: In this work, we have proposed an identification model for AIPs using a voting classifier. We used eight different feature descriptors and five conventional machine-learning classifiers. The eight feature encodings were concatenated to get a hybrid feature set. The five baseline models trained on the hybrid feature set were integrated via a voting classifier. Finally, a feature selection algorithm was used to select the optimal feature set for the construction of our final model, named IF-AIP., Results: We tested the proposed model on two independent datasets. On independent data 1, the IF-AIP model shows an improvement of 3%-5.6% in terms of accuracies and 6.7%-10.8% in terms of MCC compared to the existing methods. On the independent dataset 2, our model IF-AIP shows an overall improvement of 2.9%-5.7% in terms of accuracy and 8.3%-8.6% in terms of MCC score compared to the existing methods. A comparative performance analysis was conducted between the proposed model and existing methods using a set of 24 novel peptide sequences. Notably, the IF-AIP method exhibited exceptional accuracy, correctly identifying all 24 peptides as AIPs. The source code, pre-trained models, and all datasets are made available at https://github.com/Mir-Saima/IF-AIP., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

The cytokine interleukin-4 (IL-4) plays an important role in our immune system. IL-4 leads the way in the differentiation of naïve T-helper 0 cells (Th0) to T-helper 2 cells (Th2). The Th2 responses are characterized by the release of IL-4. CD4+ T cells produce the cytokine IL-4 in response to exogenous parasites. IL-4 has a critical role in the growth of CD8+ cells, inflammation, and responses of T-cells. We propose an ensemble model for the prediction of IL-4 inducing peptides. Four feature encodings were extracted to build an efficient predictor: pseudo-amino acid composition, amphiphilic pseudo-amino acid composition, quasi-sequence-order, and Shannon entropy. We developed an ensemble learning model fusion of random forest, extreme gradient boost, light gradient boosting machine, and extra tree classifier in the first layer, and a Gaussian process classifier as a meta classifier in the second layer. The outcome of the benchmarking testing dataset, with a Matthews correlation coefficient of 0.793, showed that the meta-model (Meta-IL4) outperformed individual classifiers. The highest accuracy achieved by the Meta-IL4 model is 90.70%. These findings suggest that peptides that induce IL-4 can be predicted with reasonable accuracy. These models could aid in the development of peptides that trigger the appropriate Th2 response., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Inc.)

Background: Retinitis Pigmentosa (RP) is a clinically and genetically progressive retinal dystrophy associated with severe visual impairments and sometimes blindness, the most common syndromic form of which is Usher syndrome (USH). This study aimed to further increase understanding of the spectrum of RP in the Khyber Pakhtunkhwa region of Pakistan., Methodology: Four consanguineous families of Pashtun ethnic group were investigated which were referred by the local collaborating ophthalmologists. In total 42 individuals in four families were recruited and investigated using whole exome and dideoxy sequencing. Among them, 20 were affected individuals including 6 in both family 1 and 2, 5 in family 3 and 3 in family 4., Result: Pathogenic gene variants were identified in all four families, including two in cone dystrophy and RP genes in the same family (PDE6C; c.480delG, p.Asn161ThrfsTer33 and TULP1; c.238 C > T, p.Gln80Ter) with double-homozygous individuals presenting with more severe disease. Other pathogenic variants were identified in MERTK (c.2194C > T, p.Arg732Ter), RHO (c.448G > A, p.Glu150Lys) associated with non-syndromic RP, and MYO7A (c.487G > A, p.Gly163Arg) associated with USH. In addition, the reported variants were of clinical significance as the PDE6C variant was detected novel, whereas TULP1, MERTK, and MYO7A variants were detected rare and first time found segregating with retinal dystrophies in Pakistani consanguineous families., Conclusions: This study increases knowledge of the genetic basis of retinal dystrophies in families from Pakistan providing information important for genetic testing and diagnostic provision particularly from the Khyber Pakhtunkhwa region., (© 2023. The Author(s).)

After the COVID-19 pandemic, there was an increasing demand for remote learning and an expansion in the substitution of traditional practical sessions with lab-based virtual tools. This study aimed to assess the effectiveness of virtual labs in practicing biochemical experiments and to examine the student's feedback regarding this tool. Virtual and traditional labs training were compared in teaching qualitative analysis of proteins and carbohydrates experiments for first-year medical students. Students' achievements were assessed, and their satisfaction regarding virtual labs was estimated using a questionnaire. A total of 633 students were enrolled in the study. There was a significant increase in the average scores of students performing the virtual lab of protein analysis compared with those trained in a real lab and those who watched videos explaining the experiment (p < 0.001). The opposite was noticed in the qualitative analysis of carbohydrates with significantly high grades of students trained conventionally compared with those who practiced with virtual labs (p < 0.001). Students' feedback rates on the virtual labs were high (>70% satisfaction rate). Most students believed virtual labs were supported with a clear explanation, yet they thought it did not give a realistic experience. Students accepted virtual labs, but they still prefer using them as preparatory to classic labs. In conclusion, virtual labs can offer good laboratory practice in the Medical Biochemistry course. Their impact on students' learning might be increased if selected cautiously and implemented properly in the curriculum., (© 2023 International Union of Biochemistry and Molecular Biology.)

Modern electronics are founded on switching the electrical signal by radio frequency electromagnetic fields on the nanosecond time scale, limiting the information processing to the gigahertz speed. Recently, optical switches have been demonstrated using terahertz and ultrafast laser pulses to control the electrical signal and enhance the switching speed to the picosecond and a few hundred femtoseconds time scale. Here, we exploit the reflectivity modulation of the fused silica dielectric system in a strong light field to demonstrate the optical switching (ON/OFF) with attosecond time resolution. Moreover, we present the capability of controlling the optical switching signal with complex synthesized fields of ultrashort laser pulses for data binary encoding. This work paves the way for establishing optical switches and light-based electronics with petahertz speeds, several orders of magnitude faster than the current semiconductor-based electronics, opening a new realm in information technology, optical communications, and photonic processor technologies.

In human pose estimation methods based on graph convolutional architectures, the human skeleton is usually modeled as an undirected graph whose nodes are body joints and edges are connections between neighboring joints. However, most of these methods tend to focus on learning relationships between body joints of the skeleton using first-order neighbors, ignoring higher-order neighbors and hence limiting their ability to exploit relationships between distant joints. In this paper, we introduce a higher-order regular splitting graph network (RS-Net) for 2D-to-3D human pose estimation using matrix splitting in conjunction with weight and adjacency modulation. The core idea is to capture long-range dependencies between body joints using multi-hop neighborhoods and also to learn different modulation vectors for different body joints as well as a modulation matrix added to the adjacency matrix associated to the skeleton. This learnable modulation matrix helps adjust the graph structure by adding extra graph edges in an effort to learn additional connections between body joints. Instead of using a shared weight matrix for all neighboring body joints, the proposed RS-Net model applies weight unsharing before aggregating the feature vectors associated to the joints in order to capture the different relations between them. Experiments and ablations studies performed on two benchmark datasets demonstrate the effectiveness of our model, achieving superior performance over recent state-of-the-art methods for 3D human pose estimation.

Background: Tobacco tax increase is considered as one of the most effective means to reduce tobacco consumption and its consequences. An increase in taxes, which results in an increase in the price of tobacco products, reduces consumption. Historically, a number of studies estimated the responsiveness of quantity demanded to a change in price-the price elasticity of demand-of tobacco products in Bangladesh. However, the government's stronger commitment to reducing tobacco use, rising standard of living, rapidly changing cultural norms due to globalisation, and the substantial fall in tobacco use seen in GATS 2017 necessitate an updated measure of price elasticity of tobacco use, which will allow for more accurate answers to questions of tobacco tax policy in the country. This study endeavours to fill this gap in the literature on demand for tobacco products in Bangladesh., Objective: To estimate the price elasticity of demand for tobacco products, namely cigarettes, biris and smokeless tobacco (SLT) products with the 2016 household income and expenditure survey data in Bangladesh., Methods: We used the Deaton model (1997) to estimate the price elasticities of demand for tobacco products using the Household Income and Expenditure Survey (HIES) 2016 dataset of the Bangladesh Bureau of Statistics. The HIES 2016 surveyed 46 076 households spread over 2304 primary sampling units across the country. We have calculated own price elasticities of demand for tobacco products by expenditure groups and by regions (rural and urban)., Results: The estimates of own-price elasticity of demand for cigarette, biri and SLT products are -1.03, -1.34 and -0.30, respectively. The results show that rural households are more responsive to changes in the prices of cigarettes than urban households. Households with low expenditure are found to be more responsive to changes in the price of cigarettes than the households with high expenditure. This suggests that increases in cigarette prices at the lower end would effectively reduce cigarette consumption among the people having low expenditure and improve health equity., Conclusions: Our results suggest that the demand for smoking tobacco products is responsive to price changes. Therefore, substantial increase in the prices of tobacco products through taxation will result in significant reduction in tobacco use, particularly among the low expenditure households, while increasing government revenue., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. No commercial re-use. See rights and permissions. Published by BMJ.)

The advancement in the attosecond field and the generation of XUV attosecond pulses has enabled the study of electron dynamics in the solid-state by high harmonic generation spectroscopy. Here, we introduce new all-optical attosecond metrology to study the light-field induced electron dynamics in dielectric systems. This new methodology is based on the phase transition of a dielectric material due to its interaction with a strong light field. Hence, the charge carriers undergo an inter- and intraband transition, causing a modification in the electronic structure, dielectric constant, and optical properties of the dielectric system. Consequently, the dielectric material experiences an adiabatic semi-metal phase transition due to the strong polarizability. Therefore, the reflectivity of the dielectric system changes, following the shape of the pump field. Accordingly, the time-resolved reflectivity change measurement provides direct access to the phase transition and the related electronic dynamics of the system in real-time. In the reported experiment, a strong light field (pump pulse) induces the phase transition and modifies the fused silica sample's reflectivity, which is probed by another weak light field (probe pulse). The reflected probe beam spectrum is acquired as a function of the time delay between the pump and probe pulses. This measurement shows that the real-time phase transition dynamic (and reflectivity change) follows the pump field shape. Moreover, the reflectivity measurements have been recorded at different pump field strengths performed under the same conditions. The reflectivity trace shows a retardation phase delay at a higher driver field strength. The delay response-retrieved from the recorded reflectivity traces-is in the order of a few hundred attoseconds. In addition, the results show that the delay response monotonically increases as the trigger field escalates. Furthermore, the reflectivity measurements have been acquired for another dielectric system (CaF 2 ). The electronic delay response shows the same linear behavior increase as that of the SiO 2 system. This work establishes a universal new attosecond metrology for measuring the electron dynamics and delay response in different materials.

A teacher plays a pivotal role in grooming a society and paves way for its social and economic developments. Teaching is a dynamic role and demands continuous adaptation. A teacher adopts teaching techniques suitable for a certain discipline and a situation. A thorough, detailed, and impartial observation of a teacher is a desideratum for adaptation of an effective teaching methodology and it is a laborious exercise. An automatic strategy for analyzing a teacher's teaching methodology in a classroom environment is suggested in this work. The proposed strategy recognizes a teacher's actions in videos while he is delivering lectures. In this study, 3D CNN and Conv2DLSTM with time-distributed layers are used for experimentation. A range of actions are recognized for a complete classroom session during experimentation and the reported results are considered effective for analysis of a teacher's teaching technique., Competing Interests: The authors have declared that no competing interests exist.

Internet of Vehicles (IoV) is an application of the Internet of Things (IoT) network that connects smart vehicles to the internet, and vehicles with each other. With the emergence of IoV technology, customers have placed great attention on smart vehicles. However, the rapid growth of IoV has also caused many security and privacy challenges that can lead to fatal accidents. To reduce smart vehicle accidents and detect malicious attacks in vehicular networks, several researchers have presented machine learning (ML)-based models for intrusion detection in IoT networks. However, a proficient and real-time faster algorithm is needed to detect malicious attacks in IoV. This article proposes a hybrid deep learning (DL) model for cyber attack detection in IoV. The proposed model is based on long short-term memory (LSTM) and gated recurrent unit (GRU). The performance of the proposed model is analyzed by using two datasets-a combined DDoS dataset that contains CIC DoS, CI-CIDS 2017, and CSE-CIC-IDS 2018, and a car-hacking dataset. The experimental results demonstrate that the proposed algorithm achieves higher attack detection accuracy of 99.5% and 99.9% for DDoS and car hacks, respectively. The other performance scores, precision, recall, and F1-score, also verify the superior performance of the proposed framework.

Background: Many primary care patients receive both medical and chiropractic care; however, interprofessional relations between physicians and chiropractors are often suboptimal which may adversely affect care of shared patients. We surveyed Canadian family physicians in 2010 to explore their attitudes towards chiropractic and re-administered the same survey a decade later to explore for changes in attitudes., Methods: A 50-item survey administered to a random sample of Canadian family physicians in 2010, and again in 2019, that inquired about demographic variables, knowledge and use of chiropractic. Imbedded in our survey was a 20-item chiropractic attitude questionnaire (CAQ); scores could range from 0 to 80 with higher scores indicating more positive attitudes toward chiropractic. We constructed a multivariable regression model to explore factors associated with CAQ scores., Results: Among eligible physicians, 251 of 685 in 2010 (37% response rate) and 162 of 2429 in 2019 (7% response rate) provided a completed survey. Approximately half of respondents (48%) endorsed a positive impression of chiropractic, 27% were uncertain, and 25% held negative views. Most respondents (72%) referred at least some patients for chiropractic care, mainly due to patient request or lack of response to medical care. Most physicians believed that chiropractors provide effective therapy for some musculoskeletal complaints (84%) and disagreed that chiropractic care was beneficial for non-musculoskeletal conditions (77%). The majority agreed that chiropractic care was a useful supplement to conventional care (65%) but most respondents (59%) also indicated that practice diversity among chiropractors presented a barrier to interprofessional collaboration. In our adjusted regression model, attitudes towards chiropractic showed trivial improvement from 2010 to 2019 (0.31 points on the 80-point CAQ; 95%CI 0.001 to 0.62). More negative attitudes were associated with older age (- 1.55 points for each 10-year increment from age 28; 95%CI - 2.67 to - 0.44), belief that adverse events are common with chiropractic care (- 1.41 points; 95% CI - 2.59 to - 0.23) and reported use of the research literature (- 6.04 points; 95% CI - 8.47 to - 3.61) or medical school (- 5.03 points; 95% CI  - 7.89 to - 2.18) as sources of knowledge on chiropractic. More positive attitudes were associated with endorsing a relationship with a specific chiropractor (5.24 points; 95% CI 2.85 to 7.64), family and friends (4.06 points; 95% CI 1.53 to 6.60), or personal treatment experience (4.63 points; 95% CI 2.14 to 7.11) as sources of information regarding chiropractic., Conclusions: Although generally positive, Canadian family physicians' attitudes towards chiropractic are diverse, and most physicians felt that practice diversity among chiropractors was a barrier to interprofessional collaboration., (© 2021. The Author(s).)

Background: Adolescence is the last opportunity to reverse any growth faltering accumulated from fetal life through childhood and it is considered a crucial period to optimize human development. In Bangladesh, a growing double burden of underweight and obesity in adolescents is recognized, yet limited data exists on how, when, and where to intervene. This study assesses the dynamics of growth among adolescent girls in Bangladesh, providing insight about critical junctures where faltering occurs and where immediate interventions are warranted., Methods: We pooled data from Bangladesh's Food Security and Nutrition Surveillance Project collected between 2011 and 2014 to document the age dynamics of weight and linear growth. 20,572 adolescent girls were measured for height and 19,345 for weight. We constructed growth curves for height, weight, stunting, and underweight. We also stratified growth dynamics by wealth quintile to assess socioeconomic inequities in adolescent trajectories., Results: Height-for-age z-score (HAZ) in Bangladeshi girls deteriorates throughout adolescence and especially during the early years. Mean HAZ decreases by 0.20 standard deviations (sd) per year in early adolescence (10-14 years) vs 0.06 sd/year during late adolescence (15-19 years), while stunting increases by 16 percentage points (pp) vs 6.7 pp, respectively. Conversely, BMI-for-age z-score (BAZ) increases by 0.13 sd/year in early adolescence vs 0.02 sd/year in late adolescence, and underweight decreases by 12.8 pp vs 3.2 pp. Adolescent girls in all socioeconomic groups show a similar pattern of HAZ and BAZ dynamics, but the curve for the richest quintile stays above that of the poorest across all ages., Conclusions: Trends and levels of stunting and underweight among adolescent girls in Bangladesh are worrisome, suggesting substantial linear growth faltering in early adolescence, with improving weight-for-age occurring only as linear growth slows and stops. Given the rising burden of non-communicable diseases (NCDs) in Bangladesh and emerging evidence of the link between stunting and later chronic diseases, greater attention to adolescent growth and development is needed. Our findings suggest that, to address stunting, interventions in early adolescence would have the greatest benefits. School-based interventions could be a way to target this population., Competing Interests: This project received funding from a commercial source, The World Bank Group Bangladesh, to analyze existing surveillance data collected by the BRAC James P. Grant School of Public Health as part of a large project supported by the European Union. This does not alter our adherence to PLOS ONE policies on sharing data and materials.

Introduction: Quality improvement (QI) is a growing field of inquiry in healthcare, but the reporting quality of QI studies in neonatology remains unclear. We conducted a systematic survey of the literature to assess the reporting quality of QI studies and factors associated with reporting quality., Methods: We searched Medline for publications of QI studies from 2016 to 16 April 2020. Pairs of reviewers independently screened citations and assessed reporting quality using a 31-item modified Standards for Quality Improvement Reporting Excellence, 2nd edition (SQUIRE 2.0) checklist. We reported the number (percentage) of studies that reported each item and their corresponding 95% CIs. We used Poisson regression to explore factors associated with reporting quality, namely, journal endorsement of SQUIRE 2.0, declaration of funding sources, year of publication and number of authors. The results were reported as incidence rate ratio (IRR) and 95% CI., Results: Of 1921 citations, 336 were eligible; among them, we randomly selected 100 articles to assess reporting quality. The mean (standard deviation) number of SQUIRE 2.0 items adhered to was 22.0 (4.5). Percentage of articles reporting each item varied from 26% to 100%. Journal endorsement of SQUIRE 2.0 (IRR=1.11, 95% CI 1.02 to 1.21, p=0.015), declaration of funding sources and increasing number of authors were significantly associated with better reporting., Conclusions: Reporting quality of QI studies in neonatology is inadequate. Endorsing the SQUIRE 2.0 guideline is a step that journals can implement to enhance the completeness of reporting., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

A design for a radio frequency (RF) neutron spin flipper obtained from magneto-static and neutron spin transport simulations is presented. The RF flipper constructed from this design provides a flipping probability of 0.999 or better for a beam size 6 cm wide and 15 cm high and a wavelength band between 0.4 and 0.6 nm. Three permanent magnet guide field sections with air gaps provide a linear field gradient along the beam propagation direction over a large cross-sectional area. An RF oscillator based on coupling the resonant coil of a Hartley oscillator to the excitation coil was developed, which provides a higher current and, thereby, a larger RF amplitude, as compared to a conventional RF power amplifier. Two opaque He3 neutron spin filters were employed to measure the flipping probability of the flipper with very high precision. A spatially uniform flipping probability of 0.9995(2) or higher was measured over the large cross-sectional area neutron guide. This RF neutron spin flipper will be employed in a polychromatic beam reflectometer at the National Institute of Standards and Technology Center for Neutron Research. This design can be applied to other polarized neutron instruments or applications requiring a very high continuous flipping probability of the neutron spin for a large cross-sectional area beam.

Quartz Tuning Fork (QTF) based sensors are used for Scanning Probe Microscopes (SPM), in particular for near-field scanning optical microscopy. Highly sharp Tungsten (W) tips with larger cone angles and less tip diameter are critical for SPM instead of platinum and iridium (Pt/Ir) tips due to their high-quality factor, conductivity, mechanical stability, durability and production at low cost. Tungsten is chosen for its ease of electrochemical etching, yielding high-aspect ratio, sharp tips with tens of nanometer end diameters, while using simple etching circuits and basic electrolyte chemistry. Moreover, the resolution of the SPM images is observed to be associated with the cone angle of the SPM tip, therefore Atomic-Resolution Imaging is obtained with greater cone angles. Here, the goal is to chemically etch W to the smallest possible tip apex diameters. Tips with greater cone angles are produced by the custom etching procedures, which have proved superior in producing high quality tips. Though various methods are developed for the electrochemical etching of W wire, with a range of applications from scanning tunneling microscopy (SPM) to electron sources of scanning electron microscopes, but the basic chemical etching methods need to be optimized for reproducibility, controlling cone angle and tip sharpness that causes problems for the end users. In this research work, comprehensive experiments are carried out for the production of tips from 0.4 mm tungsten wire by three different electrochemical etching techniques, that is, Alternating Current (AC) etching, Meniscus etching and Direct Current (DC) etching. Consequently, sharp and high cone angle tips are obtained with required properties where the results of the W etching are analyzed, with optical microscope, and then with field emission scanning electron microscopy (FE-SEM). Similarly, effects of varying applied voltages and concentration of NaOH solution with comparison among the produced tips are investigated by measuring their cone angle and tip diameter. Moreover, oxidation and impurities, that is, removal of contamination and etching parameters are also studied in this research work. A method has been tested to minimize the oxidation on the surface and the tips were characterized with scanning electron microscope (SEM).

Background: Nonalcoholic fatty liver disease (NAFLD) and type-2 diabetes mellitus (T2DM) have an intricate bidirectional relationship. Individuals with T2DM, not only have a higher prevalence of non-alcoholic steatosis, but also carry a higher risk of progression to nonalcoholic steatohepatitis. Experts still differ in their recommendations of screening for NAFLD among patients with T2DM., Aim: To study the prevalence of NAFLD and advanced fibrosis among our patient population with T2DM., Methods: During the study period (November 2018 to January 2020), 59 adult patients with T2DM and 26 non-diabetic control group individuals were recruited prospectively. Patients with known significant liver disease and alcohol use were excluded. Demographic data and lab parameters were recorded. Liver elastography was performed in all patients., Results: In the study group comprised of patients with T2DM and normal alanine aminotransferase levels (mean 17.8 ± 7 U/L), 81% had hepatic steatosis as diagnosed by elastography. Advanced hepatic fibrosis (stage F3 or F4) was present in 12% of patients with T2DM as compared to none in the control group. Patients with T2DM also had higher number of individuals with grade 3 steatosis [45.8% vs 11.5%, ( P < 0.00001) and metabolic syndrome (84.7% vs 11.5%, P < 0.00001)]., Conclusion: A significant number of patients with T2DM, despite having normal transaminase levels, have NAFLD, grade 3 steatosis and advanced hepatic fibrosis as measured by liver elastography., Competing Interests: Conflict-of-interest statement: All authors report no conflicts of interest., (©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.)

In this paper, we report studies of the Fermi potential and loss per bounce of ultracold neutrons (UCNs) on a deuterated scintillator (Eljen-299-02D). These UCN properties of the scintillator enable its use in a wide variety of applications in fundamental neutron research.

An important consideration when designing a magnetostatic cavity for various applications is to maximize the ratio of the volume of field homogeneity to the overall size of the cavity. We report a design of a magnetically shielded solenoid that significantly improves the transverse field gradient averaged over a volume of 1000 cm 3 by placing compensation coils around the holes in the mu-metal end caps rather than the conventional design in which the compensation coils are placed on the main solenoid. Our application is polarized 3 He-based neutron spin filters, and our goal was to minimize the volume-averaged transverse field gradient, thereby the gradient induced relaxation time, over a 3 He cell. For solenoids with end cap holes of different sizes, additional improvements in the field gradient were accomplished by introducing non-identical compensation coils centered around the non-identical holes in the end caps. The improved designs have yielded an overall factor of 7 decrease in the gradient in the solenoid, hence a factor of 50 increase in the gradient induced relaxation time of the 3 He polarization. The results from both simulation and experiments for the development of several such solenoids are presented. Whereas our focus is on the development of magnetically shielded solenoids for 3 He neutron spin filters, the approach can be applied for other applications demanding a high level of field homogeneity over a large volume.

K + -dependent Na + /Ca 2+ -exchangers (NCKX) are a relatively recently described five-member gene family of transporters which play a quantitatively significant role in neuronal Ca 2+ transport. In this review we highlight the important individual contributions these transporters make to cellular Ca 2+ homeostasis and neuronal function. Notably, different members of the family make distinct, non-redundant, contributions to critical behavioural pathways. In particular, NCKX proteins regulate the kinetics, termination and adaptation of Ca 2+ signals in sensory transduction neurons in the olfactory and visual systems. Similar contributions to shaping the spatial and temporal features of Ca 2+ signals in neurons at other key brain locations have important consequences for the circuitry influencing control of satiety, for experience-dependent motor learning and spatial working memory retention, as well as in the protection of neurons in the face of toxic stimuli. NCKX proteins are also key contributors to a variety of events in other tissues. The connection between NCKX isoform function and human phenotype and disease is an emerging area, and we anticipate that future research will reveal rich new details in the coming years., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The first complete mitochondrial genome sequence of Ailia coila from Bangladesh was determined by the bioinformatic assembly of the next generation sequencing (NGS) reads. The constructed circular mitogenome for A. coila was 16,565 bp in length which harbored the canonical 13 protein-coding genes, 22 tRNAs, 2 rRNAs. Two non-coding regions, control region, D-loop (927 bp), and origin of light strand replication, O L (30 bp) were also well conserved in the mitogenome. Among the currently reported mitochondrial genomes in the order Siluriformes, A. coila was most closely related to Eutropiichthys vacha (AB919123) with 85.63% sequence identity., Competing Interests: The authors report that they have no conflicts of interest. The authors alone are responsible for the content and writing of the paper., (© 2019 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.)

Fall induced damages are serious incidences for aged as well as young persons. A real-time automatic and accurate fall detection system can play a vital role in timely medication care which will ultimately help to decrease the damages and complications. In this paper, we propose a fast and more accurate real-time system which can detect people falling in videos captured by surveillance cameras. Novel temporal and spatial variance-based features are proposed which comprise the discriminatory motion, geometric orientation and location of the person. These features are used along with ensemble learning strategy of boosting with J48 and Adaboost classifiers. Experiments have been conducted on publicly available standard datasets including Multiple Cameras Fall ( with 2 classes and 3 classes ) and UR Fall Detection achieving percentage accuracies of 99.2, 99.25 and 99.0, respectively. Comparisons with nine state-of-the-art methods demonstrate the effectiveness of the proposed approach on both datasets.

We describe an apparatus used to measure the electron-antineutrino angular correlation coefficient in free neutron decay. The apparatus employs a novel measurement technique in which the angular correlation is converted into a proton time-of-flight asymmetry that is counted directly, avoiding the need for proton spectroscopy. Details of the method, apparatus, detectors, data acquisition, and data reduction scheme are presented, along with a discussion of the important systematic effects.

We report the first result for the electron-antineutrino angular correlation (a coefficient) in free neutron β decay from the aCORN experiment. aCORN uses a novel method in which the a coefficient is proportional to an asymmetry in proton time of flight for events where the β electron and recoil proton are detected in delayed coincidence. Data are presented from a 15 month run at the NIST Center for Neutron Research. We obtained a=-0.1090±0.0030(stat)±0.0028(sys), the most precise measurement of the neutron a coefficient reported to date.

In real time and space, four-dimensional electron microscopy (4D EM) has enabled observation of transient structures and morphologies of inorganic and organic materials. We have extended 4D EM to include liquid cells without the time resolution being limited by the response of the detector. Our approach permits the imaging of the motion and morphological dynamics of a single, same particle on nanometer and ultrashort time scales. As a first application, we studied the rotational dynamics of gold nanoparticles in aqueous solution. A full transition from the conventional diffusive rotation to superdiffusive rotation and further to a ballistic rotation was observed with increasing asymmetry of the nanoparticle morphology. We explored the underlying physics both experimentally and theoretically according to the morphological asymmetry of the nanoparticles., (Copyright © 2017, American Association for the Advancement of Science.)

Backscatter of electrons from a beta spectrometer, with incomplete energy deposition, can lead to undesirable effects in many types of experiments. We present and discuss the design and operation of a backscatter-suppressed beta spectrometer that was developed as part of a program to measure the electronantineutrino correlation coefficient in neutron beta decay (aCORN). An array of backscatter veto detectors surrounds a plastic scintillator beta energy detector. The spectrometer contains an axial magnetic field gradient, so electrons are efficiently admitted but have a low probability for escaping back through the entrance after backscattering. The design, construction, calibration, and performance of the spectrometer are discussed.

We report on design, production and implementation of a highly dispersive broadband dielectric multilayer mirror covering near ultraviolet range from 290 nm to 350 nm. The described mirrors, having 92% spectrally averaged reflectance in the ultraviolet range and ∼ 85 fs of group delay difference, that allow compression to ∼ 7 fs, provide a strong foundation for generation of few-fs pulses in the near ultraviolet.

The time it takes a bound electron to respond to the electromagnetic force of light sets a fundamental speed limit on the dynamic control of matter and electromagnetic signal processing. Time-integrated measurements of the nonlinear refractive index of matter indicate that the nonlinear response of bound electrons to optical fields is not instantaneous; however, a complete spectral characterization of the nonlinear susceptibility tensors--which is essential to deduce the temporal response of a medium to arbitrary driving forces using spectral measurements--has not yet been achieved. With the establishment of attosecond chronoscopy, the impulsive response of positive-energy electrons to electromagnetic fields has been explored through ionization of atoms and solids by an extreme-ultraviolet attosecond pulse or by strong near-infrared fields. However, none of the attosecond studies carried out so far have provided direct access to the nonlinear response of bound electrons. Here we demonstrate that intense optical attosecond pulses synthesized in the visible and nearby spectral ranges allow sub-femtosecond control and metrology of bound-electron dynamics. Vacuum ultraviolet spectra emanating from krypton atoms, exposed to intense waveform-controlled optical attosecond pulses, reveal a finite nonlinear response time of bound electrons of up to 115 attoseconds, which is sensitive to and controllable by the super-octave optical field. Our study could enable new spectroscopies of bound electrons in atomic, molecular or lattice potentials of solids, as well as light-based electronics operating on sub-femtosecond timescales and at petahertz rates.

Ultrafast electron microscopy (UEM) is a pivotal tool for imaging of nanoscale structural dynamics with subparticle resolution on the time scale of atomic motion. Photon-induced near-field electron microscopy (PINEM), a key UEM technique, involves the detection of electrons that have gained energy from a femtosecond optical pulse via photon-electron coupling on nanostructures. PINEM has been applied in various fields of study, from materials science to biological imaging, exploiting the unique spatial, energy, and temporal characteristics of the PINEM electrons gained by interaction with a "single" light pulse. The further potential of photon-gated PINEM electrons in probing ultrafast dynamics of matter and the optical gating of electrons by invoking a "second" optical pulse has previously been proposed and examined theoretically in our group. Here, we experimentally demonstrate this photon-gating technique, and, through diffraction, visualize the phase transition dynamics in vanadium dioxide nanoparticles. With optical gating of PINEM electrons, imaging temporal resolution was improved by a factor of 3 or better, being limited only by the optical pulse widths. This work enables the combination of the high spatial resolution of electron microscopy and the ultrafast temporal response of the optical pulses, which provides a promising approach to attain the resolution of few femtoseconds and attoseconds in UEM.

Extreme ultraviolet (EUV) high-harmonic radiation emerging from laser-driven atoms, molecules or plasmas underlies powerful attosecond spectroscopy techniques and provides insight into fundamental structural and dynamic properties of matter. The advancement of these spectroscopy techniques to study strong-field electron dynamics in condensed matter calls for the generation and manipulation of EUV radiation in bulk solids, but this capability has remained beyond the reach of optical sciences. Recent experiments and theoretical predictions paved the way to strong-field physics in solids by demonstrating the generation and optical control of deep ultraviolet radiation in bulk semiconductors, driven by femtosecond mid-infrared fields or the coherent up-conversion of terahertz fields to multi-octave spectra in the mid-infrared and optical frequencies. Here we demonstrate that thin films of SiO2 exposed to intense, few-cycle to sub-cycle pulses give rise to wideband coherent EUV radiation extending in energy to about 40 electronvolts. Our study indicates the association of the emitted EUV radiation with intraband currents of multi-petahertz frequency, induced in the lowest conduction band of SiO2. To demonstrate the applicability of high-harmonic spectroscopy to solids, we exploit the EUV spectra to gain access to fine details of the energy dispersion profile of the conduction band that are as yet inaccessible by photoemission spectroscopy in wide-bandgap dielectrics. In addition, we use the EUV spectra to trace the attosecond control of the intraband electron motion induced by synthesized optical transients. Our work advances lightwave electronics in condensed matter into the realm of multi-petahertz frequencies and their attosecond control, and marks the advent of solid-state EUV photonics.

Butyrylcholinesterase (BChE) exists mainly at neuromuscular junctions and plays an important role in the hydrolyzing mechanism of neurotransmitter acetylcholine. A variety of compounds have been produced in order to inhibit the function of BChE. We here investigate the specific interactions between BChE and some ligands (Kx) with large binding affinity to BChE, using ligand-docking, classical molecular mechanics and ab initio fragment molecular orbital (FMO) methods. The binding energies between BChE and Kx evaluated by the FMO method have a correlation with the 50% inhibition concentration obtained by the previous experiments. In addition, the FMO calculations highlight that Asp70, Trp82 and Tyr128 residues of BChE contribute significantly to the binding between BChE and Kx. Based on the results, we propose some novel ligands and elucidate that one of the proposed ligands can bind strongly to BChE. The present results are useful for developing potent inhibitors to BChE., (Copyright © 2014 Elsevier Inc. All rights reserved.)

The tyrosinase is a bifunctional, copper-containing enzyme widely distributed in the phylogenetic tree. This enzyme is involved in the production of melanin and some other pigments in humans, animals and plants, including skin pigmentations in mammals, and browning process in plants and vegetables. Therefore, enzyme inhibitors has been under the attention of the scientist community, due to its broad applications in food, cosmetic, agricultural and medicinal fields, to avoid the undesirable effects of abnormal melanin overproduction. However, the research of novel chemical with antityrosinase activity demands the use of more efficient tools to speed up the tyrosinase inhibitors discovery process. This chapter is focused in the different components of a predictive modeling workflow for the identification and prioritization of potential new compounds with activity against the tyrosinase enzyme. In this case, two structure chemical libraries Spectrum Collection and Drugbank are used in this attempt to combine different virtual screening data mining techniques, in a sequential manner helping to avoid the usually expensive and time consuming traditional methods. Some of the sequential steps summarize here comprise the use of drug-likeness filters, similarity searching, classification and potency QSAR multiclassifier systems, modeling molecular interactions systems, and similarity/diversity analysis. Finally, the methodologies showed here provide a rational workflow for virtual screening hit analysis and selection as a promissory drug discovery strategy for use in target identification phase.

Current evidence suggests that endogenous dopamine may act as a neurotoxin following its oxidation to an oquinone and reaction with cellular thiols, which are neutoxic, which may occur spontaneously or via reaction with tyrosinase or some other enzymes. Tyrosinase (E.C. 1.14.18.1) with two cupper ions coordinated by three histidines is a bifunctional enzyme that catalyses both the hydroxylation of tyrosine to L-DOPA and the consequent oxidation of the resulting catechol-containing species to an o-quinone. Therefore, tyrosinase may play a role in neuromelanin formation in the brain and could be central to dopamine neurotoxicity by contributing to the neurodegeneration associated with Parkinson's disease. In the present study, inhibitory effect of ascorbic acid against tyrosinase has been investigated and it has shown a remarkable inhibitory effect in in vitro assays. Then, the in silico-based experiments established through molecular docking calculations and scoring, docking search algorithm, and data plotting indicated that ascorbic acid is strong inhibitor of tyrosinase by interacting with four amino acid units (histidine 263, serine 282, phenylalanine 264, and valin 283) in the active site of the enzyme. The compound also had two long distant hydrogen bindings with Cu1 and Cu2 with distances of 3.57 and 3.41 A, respectively, through its O5 atom.