Structural and Functional Insight of Helicobacter pylori Translation Initiation Factor IF1 (HpIF1) in Protein Biosynthesis and Rational Design of New Antimicrobial Candidates

Helicobacter pylori (H. pylori) is a Gram-negative bacterium that colonizes the human gastric mucosa and is associated with peptic ulcer disease and gastric cancer. Bacterial protein synthesis is a fundamental metabolic process occurring in all bacteria and is a validated target of antibiotics; however, the precise structural mechanism of H. pylori protein biosynthesis remains unknown. Protein synthesis contains four stages, and translational initiation is the most important and highly regulated critical step, involving three initiation factors (IF1, IF2, IF3) and other key components. IF1 plays a vital role in regulating this step by binding to the 30S ribosomal subunit cooperatively with other initial components. However, H. pylori’s IF1 structure is unknown. Using a computational model, this study investigated the interaction between H. pylori initiation factor IF1 and the 30S ribosomal subunit. Hp-IF1 was subcloned into pET24b vector for constructing recombinant DNA plasmid- pET24b-Hp-IF1 DNA plasmid. The recombinant DNA plasmid was used to express the Hp-IF1 protein by the E. coli expression system. The proteins were purified by column chromatography, which were used for NMR structural analysis. The Hp-IF1 protein structure was predicted and used for building the complex model binding with the 30S subunit. We elucidated the structure of the IF1-bound 30S complex, revealing the importance of a short α-helix in IF1 for ribosomal binding and function. A peptide derived from this α-helix Hp-IF1 was designed and tested by MIC assay showing broad-spectrum activity against Gram-negative and positive bacteria, including H. pylori. The peptide shows a low cytotoxicity effect against human embryonic kidney (HEK-293) cells. These results suggest Hp-IF1 peptide as a potential compound for the development of new antimicrobial agents

Numerical Study of Owls’ Leading-Edge Serrations

The silent flight ability of owls is often attributed to their unique wing morphology and its interaction with their wingbeat kinematics. Among these distinctive morphological features, leading-edge serrations stand out – these are rigid, miniature, hook-like patterns located at the leading edge of the primary feathers of their wings. It had been hypothesized that these leading-edge serrations serve as a passive flow control mechanism, influencing the aerodynamic performance and potentially affecting the boundary layer development over the wing, subsequently influencing wake flow dynamics. Despite being the subject of research spanning multiple decades, a consensus regarding the aerodynamic mechanisms underpinning owls’ leading-edge serrations remains elusive. While the literature extensively explores the aerodynamic and aeroacoustic properties of serrated wing geometries, the predominant focus had been on owl-like serrations, including sawtooth patterns, wavy configurations, cylindrical shapes, and slitted variations. This emphasis has often overshadowed the authentic geometry of owl wing serrations, which are notably shorter than the wing\u27s chord and oriented at an angle relative to the freestream airflow. In order to shed light on the flow dynamics associated with owls\u27 leading-edge serrations, this study delves into numerically simulating the flow field surrounding an owl wing, meticulously replicating the serrated leading-edge geometry, at an intermediate chord-based Reynolds number (40000). A direct numerical simulation (DNS) approach is employed to simulate the fluid flow problem, where the Navier-Stokes equations for incompressible flow are solved on a Cartesian grid with sufficient resolution to resolve all the relevant flow scales, while the wing is represented using an immersed boundary method. Two wing planforms are considered for numerical analysis: one featuring leading-edge serrations and another without them. The findings suggest that the serrations improve suction surface flow by promoting sustained flow reattachment via streamwise vorticity generation at the shear layer, prompting weaker reverse flow, and thus augmenting stall resistance. However, aerodynamic performance is negatively impacted due to the shear layer passing through the serration array which results in altered surface pressure distribution over the upper surface. It is also found that serration increases turbulence level in the downstream flow. Turbulent momentum transfer near the trailing edge is significantly increased due to the presence of serrations upstream the flow which also influences the mechanisms associated with separation vortex formation and its subsequent development over the upper surface of the wing. Turbulent budget analysis at the leading-edge shear layer demonstrates that serration reduces turbulence production in the immediate vicinity; however, the reduction effect does not persist further downstream when the shear layer rolls up, and eventually merges with a large separation vortex. In the wake of the serrated wing, integral scale was found to be larger than the smooth wing which implies that serrations at the leading-edge does not promote scale reduction at the wake

Numerical Study of Owls\u27 Leading-edge Serrations

Owls\u27 silent flight is commonly attributed to their special wing morphology combined with wingbeat kinematics. One of these special morphological features is known as the leading-edge serrations: rigid miniature hook-like patterns found at the primaries of the wings\u27 leading-edge. It has been hypothesized that leading-edge serrations function as a passive flow control mechanism, impacting the aerodynamic performance. To elucidate the flow physics associated with owls\u27 leading-edge serrations, we investigate the flow-field characteristic around a barn owl wing with serrated leading-edge geometry positioned at 20° angle of attack for a Reynolds number of 40 000. We use direct numerical simulations, where the incompressible Navier–Stokes equations are solved on a Cartesian grid with sufficient resolution to resolve all the relevant flow scales, while the wing is represented using an immersed boundary method. We have simulated two wing planforms: with serrations and without. Our findings suggest that the serrations improve suction surface flow by promoting sustained flow reattachment via streamwise vorticity generation at the shear layer, prompting weaker reverse flow, thus augmenting stall resistance. Aerodynamic performance is negatively impacted due to the shear layer passing through the serration array, which results in altered surface pressure distribution over the upper surface. In addition, we found that serrations increase turbulence level in the downstream flow. Turbulent momentum transfer near the trailing edge increased due to the presence of serrations upstream the flow, which also influences the mechanisms associated with separation vortex formation and its subsequent development over the upper surface of the wing. This article was published as Open Access through the CCU Libraries Open Access Publishing Fund. The article was first published in Physics of Fluids: https://doi.org/10.1063/5.017414

PithaNet: A transfer learning-based approach for traditional pitha classification

Pitha, pithe, or peetha are all Bangla words referring to a native and traditional food of Bangladesh as well as some areas of India, especially the parts of India where Bangla is the primary language. Numerous types of pithas exist in the culture and heritage of the Bengali and Bangladeshi people. Pithas are traditionally prepared and offered on important occasions in Bangladesh, such as welcoming a bride grooms, or bride, entertaining guests, or planning a special gathering of family, relatives, or friends. The traditional pitha celebration and pitha culture are no longer widely practiced in modern civilization. Consequently, the younger generation is unfamiliar with our traditional pitha culture. In this study, an effective pitha image classification system is introduced. convolutional neural network (CNN) pre-trained models EfficientNetB6, ResNet50, and VGG16 are used to classify the images of pitha. The dataset of traditional popular pithas is collected from different parts of Bangladesh. In this experiment, EfficientNetB6 and ResNet50 show nearly 90% accuracy. The best classification result was obtained using VGG16 with 92% accuracy. The main motive of this study is to revive the Bengali pitha tradition among young people and people worldwide, which will encourage many other researchers to pursue research in this domain

The role of parafacial neurons in the control of breathing during exercise

Neuronal cell groups residing within the retrotrapezoid nucleus (RTN) and C1 area of the rostral ventrolateral medulla oblongata contribute to the maintenance of resting respiratory activity and arterial blood pressure, and play an important role in the development of cardiorespiratory responses to metabolic challenges (such as hypercapnia and hypoxia). In rats, acute silencing of neurons within the parafacial region which includes the RTN and the rostral aspect of the C1 circuit (pFRTN/C1), transduced to express HM4D (Gi-coupled) receptors, was found to dramatically reduce exercise capacity (by 60%), determined by an intensity controlled treadmill running test. In a model of simulated exercise (electrical stimulation of the sciatic or femoral nerve in urethane anaesthetised spontaneously breathing rats) silencing of the pFRTN/C1 neurons had no effect on cardiovascular changes, but significantly reduced the respiratory response during steady state exercise. These results identify a neuronal cell group in the lower brainstem which is critically important for the development of the respiratory response to exercise and, determines exercise capacity

Grey-Taguchi Approach to Optimize Fused Deposition Modeling Process in Terms of Mechanical Properties and Dimensional Accuracy

Fused Deposition Modeling (FDM) is a process that allows for the rapid production of functional parts through the deposition of fused material layers in a sequential manner. FDM has flexibility and the potential to create complicated parts. This study aims to optimize the FDM process parameters in terms of tensile strength, flexural strength, and longitudinal shrinkage using the Grey-Taguchi approach. The input parameters chosen to study the effects on dimension and mechanical properties are layer thickness, the raster angle, fill density, the number of contours, printing temperature, and printing speed. The Taguchi L27 orthogonal array is used as the statistical design of experiment (DOE) technique to assess how the FDM process behaves with the change in process input parameters selected. The ANOVA test was used to assess the contribution and implications of each response factor of the FDM process on the FDM process. Additionally, the optimization of multiple characteristics is done by Grey relational analysis. Optimal parameter settings that minimize longitudinal shrinkage and maximize tensile and flexural strengths concurrently are 0.2 mm of layer thickness, 90-degree raster angle, fill density of 30, 16 numbers of contours, 230℃ printing temperature, and a printing speed of 60 mm/s

Collaborative lexicon development for Bangla

Includes bibliographical references (page 7).This paper addresses the issue of building a Bangla lexicon with a collaborative effort through stand alone application and web based interface. The words in the lexicon will be annotated with a combination of tags addressing Parts-of-speech, syntactic, semantic and other grammatical features. Bangla words have been classified into several different parts – of – speech categories including various major word groups and subgroups. This paper aims to provide an integrated user – friendly software interface to the user to annotate a large existing Bangla word set and proposes a mechanism to collaboratively integrate linguists and other interested people into the lexicon build up process. The effort will be a significant progress towards development of a properly annotated lexicon. The outcome of the effort will significantly help in the processes of Morphological Analysis, Automatic grammar Extraction and machine translation for Bangla.Dewan Shahriar Hossain PavelAsif Iqbal SarkarFaisal Muhammad ShahMumit Kha

SURVIVAL ASSESSMENT OF PATHOGENIC BACTERIA WITH ANTIBIOTIC RESISTANCE TRAITS FROM FRESH SUMMER ROYAL GRAPE : IN VITRO MICROBIAL CHALLENGE TEST

Table grape act as a popular and mouthwatering fruit supplement over the world. Unhygienic handling of these fruits can possess a diverse threat to public health safety. Moreover, the fruit juice can serve as a nutrient for bacterial growth as well if kept in an unsanitary condition. For this purpose, five imported grape samples (Red Globe, Perlette, Calmeria, Princess and Summer Royal) were tested to assess the presence of pathogenic bacteria and drug-resistant pattern of the isolates. The total bacterial count (TBC) and total fungal count (TFC) showed the presence large amount of bacterial (ranged from 4.4 x 10(4) to 8.1 x 10(7)) and fungal population on the grapes samples, especially on the skin part of the fruits. Several pathogenic isolates, Escherichia coli, Staphylococcus spp., and Pseudomonas spp. were isolated from tested grape samples. However, the presence of Salmonella spp., Shigella spp., Vibrio spp. and Klebsiella spp. were not found from any of the samples. The concerning part of the present study was drug-resistant bacterial strains isolated from supplied Fresh Summer Royal Grape. The most of the isolated bacterial spp. were resistant to all most all of the commonly used antibiotics such as ampicillin (10 mu g), trimethoprim/sulfamethoxazole (25 mu g), tetracycline (30 mu g), ceftriaxone (30 mu g), imipenem (10 mu g), chloramphenicol (30 mu g), azithromycin (15 mu g), novobiocin (30 mu g), vancomycin (30 mu g), penicillin G (10 mu g), ciprofloxacin (5 mu g), neomycin (30 mu g), levofloxacin (5 mu g), kanamycin (30 mu g) and cefiximycin (5 mu g). No grape samples showed any kind of antimicrobial activity against both pathogenic and non-pathogenic bacteria. The survival pattern of inoculated bacterial samples in the grape sample showed a slight decrease in growth in the course of time.Peer reviewe

Application of Numerical Method in Assessing the Variations in Pile Group Efficiency under Different Circumstances

Rapid urbanization creates a demand to expand the cities where using pile foundation became a recurrent practice. To ensure sustainability of projects pile load tests are important but may not be always feasible in terms of costing, on-site constrains etc. In this circumstance numerical analysis is a good alternate to estimate precise pile load capacity rather than conventional conservative approaches. This research illustrates the pile group efficiency fluctuation due to pile diameter, spacing, pile number and orientation in prescribed sandy soils. Using the conventional method the individual pile capacities are calculated for a constant depth with variable diameters and soil profiles. For simulating the piles, geometric models of sandy soils with sufficient boundaries are generated in PLAXIS 3D FOUNDATION software where the parameters of pile and soil components are considered as per predetermined values from reliable references. The analysis results have thoroughly been scrutinized by plotting several graphs at different aspects. The outcomes indicate that the conventional pile spacing i.e. 2.5D to 3.5D has an insignificant effect on pile group efficiency, irrespective to pile diameter and soil type. It also exhibits that the increment of pile number significantly decreases pile group efficiency for diameters of 600mm, 800mm, 1000mm and 1200mm in sandy soils. With a few exceptions as the diameter of the pile increases, the group efficiency decreases. The arrangement of piles in group has minor impact on pile group efficiency which enhances onsite flexibility. It is expected that these outcomes will facilitate the practicing engineers for efficient solutions

Multidrug Resistance in Cancer: Understanding Molecular Mechanisms, Immunoprevention and Therapeutic Approaches

Cancer is one of the leading causes of death worldwide. Several treatments are available for cancer treatment, but many treatment methods are ineffective against multidrug-resistant cancer. Multidrug resistance (MDR) represents a major obstacle to effective therapeutic interventions against cancer. This review describes the known MDR mechanisms in cancer cells and discusses ongoing laboratory approaches and novel therapeutic strategies that aim to inhibit, circumvent, or reverse MDR development in various cancer types. In this review, we discuss both intrinsic and acquired drug resistance, in addition to highlighting hypoxia- and autophagy-mediated drug resistance mechanisms. Several factors, including individual genetic differences, such as mutations, altered epigenetics, enhanced drug efflux, cell death inhibition, and various other molecular and cellular mechanisms, are responsible for the development of resistance against anticancer agents. Drug resistance can also depend on cellular autophagic and hypoxic status. The expression of drug-resistant genes and the regulatory mechanisms that determine drug resistance are also discussed. Methods to circumvent MDR, including immunoprevention, the use of microparticles and nanomedicine might result in better strategies for fighting cancer