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Purpose: Local muskmelon germplasm is being lost because of genetic erosion caused by the replacement of hybrid varieties, lack of conservation climate change, etc. Particularly, the foremost requisites of the industry for muskmelon is a genetic diversity assessment of landraces for identification and trait improvement. Therefore, this study was conducted to estimate the genetic diversity of muskmelon germplasm Research Method: Forty-two muskmelon (Cucumis melo L.) germplasm was collected from different geographical territories of Bangladesh and was studied to identify the morphological diversity among the germplasm using an augmented design. Thirty-four (34) agro-morphological characters were recorded, of which twenty-eight (28) were scored as qualitative characters and six (6) were measured as quantitative characters. Findings: In qualitative characters, variations in morphometrics were found such as the fruit’s shape, and different color patterns of fruit skin and flesh, etc. A maximum coefficient of variation of 73.5 % was estimated in fruit weight. Principal Component Analysis (PCA) of different quantitative traits was used to distinguish muskmelon germplasm. The cumulative percentage of variance reached 75.7% by the first two PCA components. Germplasm RC-186, IAH-194, IAH-207, AHM-15, IAH-197, IAH-345, AC-422, and RAI-239, were divergent from others concerning traits such as early maturity, fruit length, width, and weight. Clustering of accessions by D²statistic resulted in five clusters and cluster III was found to be the largest containing twenty-two (22) accessions. Value: This research work will be helpful for the further development of the muskmelon variety and the improvement of specific characters. [ABSTRACT FROM AUTHOR]

TiO2 is the most important and remarkable material in photocatalytic applications. In the present work, pure and doped TiO2 nanoparticles were fabricated by the sol‐gel synthesis route. The impact of the metal and nonmetal dopants on the performance of the photocatalysts was examined systematically. X‐ray diffraction (XRD) analysis affirmed the existence of anatase and rutile phases in the fabricated nanoparticles. The diffuse reflectance spectroscopy (DRS) analysis confirmed that all doped TiO2 nanoparticles have a lower bandgap than undoped TiO2, and (N, Cu, Ag)‐doped TiO2 nanoparticles having the lowest bandgap (2.38 eV), demonstrating that metal‐metal‐nonmetal multidoping improves TiO2′s sensitivity towards visible light. In comparison to pure and other doped TiO2 nanoparticles, methylene blue (MB) photodegrades at a faster rate (rate constant of 0.04878 min−1) with the highest photocatalytic activity (99.61 % MB degradation) on the surface of (N, Cu, Ag)‐doped TiO2. The photocatalytic activities of TiO2 nanoparticles have been improved by multidoping in the following sequence: TiO2

OBJECTIVE: Standard phytochemical investigations were performed to identify the secondary metabolites in the methanol extract of Chaetocarpus castanocarpus bark (MECC) and investigate the neuropharmacological potential of MECC in Swiss albino mice. MATERIALS AND METHODS: Swiss albino mice were used in the forced swimming test (FST) and tail suspension test (TST) to evaluate the antidepressant effect of MECC. Also, the hole board test (HBT) and elevated plus maze (EPM) were conducted to examine anxiolytic activities. In contrast, the open field test (OFT) and hole cross test (HCT) were employed to evaluate sleeping disorders. RESULTS: Alkaloids, glycosides, flavonoids, terpenoids, coumarins, and tannins are only a few secondary metabolites identified in MECC by qualitative and quantitative phytochemical investigations. The oral administration of MECC considerably shortened the immobility duration during FST and TST. Encouraging dose-dependent anxiolytic effects were also observed in all relevant experiments compared to the control. Additionally, during the OFT and HCT assessment, a noteworthy decline in the locomotor activities of the experimental animals was observed. CONCLUSIONS: The results of this investigation suggest that the Chaetocarpus castanocarpus bark is a possible source of therapeutic candidates for treating neurological disorders. [ABSTRACT FROM AUTHOR]

Maize is being promoted as a new Rabi season crop for the coastal zone in Bangladesh, but the spread of fall armyworm (Spodoptera frugiperda) is an emergent threat that needs to be managed. The prevalence of fall armyworm was surveyed in Patuakhali (Kalapara upazila), Barguna (Amtali upazila) and Khulna (Dacope and Batiaghata upazila) districts in coastal Bangladesh using a structured questionnaire and supplemented by a survey of farmer's awareness of this pest and their current management responses. Adult populations were monitored using pheromone traps and larval populations were counted by sampling maize plants from production fields during October 2019 to April 2020. Of the 120 maize growers, 74% had >10 years farming experience but most were illiterate. They mainly cultivated hybrid maize varieties Miracle, NK 40 and BARI hybrid maize 16. All the respondents opined that different stages of maize plants were infested by fall armyworm from seedling stage. The infestation level of fall armyworm increased during February to March and they sprayed chemical insecticides 2-3 times for the management of this pest. Most of the farmers got pest management information from a pesticide retailer. The number of captured moths in pheromone traps gradually increased from December to March at each coastal district. Larvae of S. frugiperda was first observed on the 1st week of January when temperature was low and reached a peak during the 3rd week of March. Increases in maximum temperature and minimum temperature had positive associations with incidence of larvae whereas increasing relative humidity and rainfall exhibited a negative association. In conclusion, maize growers are familiar with S. frugiperda and they used chemical insecticides for the management of this pest. S. frugiperda control measures need to target the period from January and February. [ABSTRACT FROM AUTHOR]

Appropriate parental selection is the breeder's main concern to exploit the highest genetic diversity and generate superior genotypes for subsequent breeding programs. Hence, the presented investigation proceeded to evaluate 353 breeding lines of rice at three breeding zones (Rajshahi, Cumilla, and Gazipur) in Bangladesh in replicated yield trials during the Boro season of 2018-2019 to identify the best genotypes and utilize them as parental materials. Data recorded on 12 yield-related traits helped to determine the best breeding lines with higher predicted breeding values. The first five principal components (PC1, PC2, PC3, PC4, and PC5) represented more than 70% (75.1%) contribution to the variability of the data. Three hundred fifty-three rice genotypes incurred distribution into five clusters over three environments. Clusters I, II, III, IV, and V comprised 66, 51, 83, 79, and 74 genotypes, respectively. Based on estimated breeding values (EBVs), IR107971-B-B RGA-B RGA-202 showed the highest value (0.395), followed by IR 108000-B-B-B-B-13 (0.329), IR 103309-B-B RGA-B RGA-194 (0.321), IR 107982-B-41-1-2-1 (0.291), IRRI 174 (0.264), and IR 107976-B-B RGA-B RGA-254 (0.234). The lowest EBV (0.022) appeared in IR103309-B-B RGA-B RGA-204 among the top 20 genotypes. Both IR 103309-B-B RGA-B RGA-194 (0.321) and IR 107982-B-41-1-2-1 (0.291) could benefit as parents for further breeding programs having higher EBVs and higher genetic diversity. [ABSTRACT FROM AUTHOR]

We explore a model of armchair graphene nanoribbons tuned by functionalizing the edge states. Edge modifications are modeled by changing the electronic energy of the edge states in specific periodic patterns. The model can be considered to mimic a controlled doping process with different elements. The band structure, density of states, conductance, and local density of states are calculated, using the tight binding approach, Green's function methodology, and the Landauer formula. The results show interesting behaviors, which are considerably different from the properties of the perfect nanoribbons. The hybridization of conducting bands with non-conducting bands, which appear perfectly flat in the perfect ribbon, opens up and modifies gaps in conductance near the Fermi level. One particular pattern of edge functionalization causes a strong, symmetric, and systematic band gap change about the Fermi level, modifying the electronic characteristics in the energy dispersion, density of states, local density of states, and conductance. Key words: armchair GNRs, band gap, metallicity, band structure, conductance, local density of states. Nous explorons un modele de nanoruban de graphene de type armchair en fonctionnalisant les etats de bord. Ces modifications du bord sont modelisees en changeant l'energie electronique des etats de bord selon des patrons periodiques specifiques. Le modele peut etre vu comme representant un processus de dopage controle avec differents elements. Nous calculons la structure de bande, la densite d'etats, la conductance et la densite locale d'etats, en utilisant une approche liaisons fortes, la methodologie des fonctions de Green et la formule de Landauer. Les resultats montrent des comportements interessants qui sont considerablement differents des proprietes des nanorubans parfaits. L'hybridation des bandes de conduction avec celles non conductrices, qui apparait parfaitement plate dans le ruban parfait, s'ouvre ici et modifie les bandes interdites de conductance pres du niveau de Fermi. Un patron particulier de fonctionnalisation du bord cause un fort, symetrique et systematique changement de la bande interdite au voisinage du niveau de Fermi, modifiant les caracteristiques electroniques touchant la dispersion en energie, la densite d'etats, la densite locale d'etats et la conductance. [Traduit par la Redaction] Mots-cles: nanoruban de graphene de type armchair, bande interdite, metallicite, structure de bande, conductance. PACS Nos.: 72.80.Vp, 73.22.Pr., 1. Introduction Graphene nanoribbons (GNRs) are strips of graphene with infinite length and finite widths. Based on the edge structures, these are known as zigzag and armchair GNRs (AGNRs), and [...]

Theoretical investigation of the scattering of electrons and positrons from the plasma etching gas trifluoroiodomethane (CF 3 I) is presented in the present work. The investigation is carried out by taking into account the screening correction arising from a semiclassical analysis of atomic geometrical overlapping of the scattering cross-sections calculated in the independent atom approximation. The scattering system e ± -CF 3 I is studied through the calculations of the observable quantities, namely, absolute differential, Sherman function, total elastic and inelastic, momentum transfer, viscosity, ionization and total cross sections over the energy range 1 eV–1 MeV. Energy dependency of the differential cross section and Sherman function are also picturized in this work. A comparative study is carried out between scattering observables for electron impact with those for positron impact to get a better understanding of the interaction and dynamics of the collision process. The corresponding scattering quantities of the constituent atoms are calculated employing a complex optical model potential by solving the Dirac relativistic wave equations in the framework of partial wave analysis. The comparison of our results with the available experimental and theoretical data shows a reasonable agreement. [ABSTRACT FROM AUTHOR]

The present work reports the theoretical investigation of the scattering of electrons and positrons by the ethane (C 2 H 6 ) molecule over the energy range 1 eV–1 MeV. The investigation was carried out by taking into account the screening correction arising from a semiclassical analysis of the atomic geometrical overlapping of the scattering observables calculated in the independent atom approximation. The study is presented through the calculations of a broad spectrum of observable quantities, namely differential, integrated elastic, momentum transfer, viscosity, inelastic, grand total, and total ionization cross-sections and the Sherman functions. A comparative study was carried out between scattering observables for electron impact with those for positron impact to exhibit the similarity and dissimilarity arising out of the difference of the collisions of impinging projectiles with the target. Partial-wave decomposition of the scattering states within the Dirac relativistic framework employing a free-atom complex optical model potential was used to calculate the corresponding observable quantities of the constituent atoms. The results, calculated using our recipe, were compared with the experimental and theoretical works available in the literature. The Sherman function for a e ± – C 2 H 6 scattering system is presented for the first time in the literature. The addition of the screening correction to the independent atom approximation method was found to substantially reduce the scattering cross-sections, particularly at forward angles for lower incident energies. [ABSTRACT FROM AUTHOR]

This article presents a theoretical investigation of the differential, integrated, elastic, inelastic, total, momentum-transfer, and viscosity cross-sections, along with the total ionization cross-section, for elastically scattered electrons and positrons from a carbon dioxide (CO 2 ) molecule in the incident energy range of 1 eV ≤ E i ≤ 1 MeV. In addition, for the first time, we report the spin polarization of e ± − CO 2 scattering systems. The independent atom model (IAM) with screening correction (IAMS) using a complex optical potential was employed to solve the Dirac relativistic equation in partial-wave analysis. The comparison of our results with the available experimental data and other theoretical predictions shows a reasonable agreement in the intermediate- and high-energy regions. [ABSTRACT FROM AUTHOR]

Background: Soybean is an important source of food, protein and oil and hence more research is essential to increase its yield under different agro-ecological conditions, including stress. In this regard, four popular soybean varieties viz. Shohag, BDS-4, BAU-S/64 and BARI Soybean-5 were irradiated using Co60 gamma rays to create genetic variation for earliness, higher seed yield and other desirable agronomic traits. Methods: The experiments were conducted at Bangladesh Institute of Nuclear Agriculture (BINA) Headquarters farm, Mymensingh during 2006-2009 and 28 elite mutant lines were selected for evaluation. The mutant line, SBM-22 derived from mother variety BARI Soybean-5 irradiated with 300Gy of gamma rays was found to be superior compared to other mutants. Considering the superior performance of mutant SBM-22 including 28 mutants and mother check variety BARI Soybean-5, were evaluated through different trials. The evaluation trials were conducted at different agro-ecological zones of the country during Rabi season (January to April) of 2010-2018. Result: Significant variations were observed both in individual location and over locations for all traits. Reactions to major diseases and insect-pests infestation were also studied. Due to better performance of the mutant SBM-22, Bangladesh Institute of Nuclear Agriculture (BINA) applied to the National Seed Board (NSB) of Bangladesh for registration as an important soybean variety "Binasoybean-6". Consequently, the NSB of Bangladesh registered SBM-22 as an improved soybean variety in 2019 as Binasoybean-6 for commercial cultivation. [ABSTRACT FROM AUTHOR]

The study was aimed to evaluate the effect of different levels of carrot with ginger on the quality attributes of chicken nuggets. For this purpose, chicken meat samples were divided into four treatment groups viz. T0 (Control), T1 (1% ginger and 4% carrot), T2 (1% ginger and 8% carrot) and T3 (1% ginger and 12% carrot). Days of intervals were 0, 15, 30 and 45th days. Samples were preserved at -20° C for 45 days. An ANOVA of a 4×4 factorial experiment in completely randomized design having three replications per treatment was used for analyses of data. Sensory, proximate, physicochemical, biochemical and microbiological analyses were determined. Color, flavor, juiciness, tenderness and overall acceptability increased significantly (p<0.05) among the different treatment groups but decreased at different days of intervals. Dry matter (DM) content decreased significantly (p<0.05) with different treatment levels and increased with days of intervals. Crude protein (CP), Ether extract (EE) and ash content of all treatments were decreased significantly (p<0.05) among different treatment groups. Free fatty acids (FFAs), peroxide value (POV) and thiobarbituric acid reactive substances (TBARS) values were decreased significantly (p<0.05) with different treatment levels and increased with days of intervals. Total viable count (TVC), total coliform count (TCC) and total yeast mold count (TYMC) decreased significantly (p<0.05) at different treatments. On the basis of sensory, physicochemical, biochemical and microbial properties indicate that T3 was the best among treatment groups. Hence, 12% carrots with 1% ginger extracts may be recommended for formulation of value added chicken nuggets as enriched dietary fiber and natural antioxidant. [ABSTRACT FROM AUTHOR]

Bangladesh is one of the most vulnerable to climate change due to its geographic position and socio-economic context. The newly emerged land in the river channel is called char. The northern region especially Lalmonirhat, Kurigram, Gaibandha is most vulnerable. The study was carried out based on a questionnaire interview, focus group discussion, and secondary data sources from Bangladesh Meteorological Department (BMD). Climatic factors such as temperature (seasonal Tmax and Tmini, daily average Tmax and Tmini), rainfall, sunshine, relative humidity, solar radiation intensity, sea level pressure and wind speed, etc. were detailed (how much change between before 2000s'and after the 2000s') studied in these areas. These are the main drivers that influence the vulnerability dimensions resulting in livelihood strategies and access to food, water, agricultural practices, income and overall livelihood, and leads to a vicious cycle of poverty. The study helps to understand the impacts of climate change, and natural disaster-related threats in the northern char area. Also suggested that if providing necessary institutional and organizational supports for strengthening the livelihood capitals, assets, and strategy to combat or mitigate impacts of climate change aspects in Bangladesh. [ABSTRACT FROM AUTHOR]

COVID-19 is one of themost highly infectious diseases ever emerged and caused by newly discovered severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It has already led the entire world to health and economic crisis. It has invaded the whole universe all most every way. The present study demonstrates with a nine mutually exclusive compartmental model on transmission dynamics of this pandemic disease (COVID-19), with special focus on the transmissibility of symptomatic and asymptomatic infection from susceptible individuals. Herein, the compartmental model has been investigated with mathematical analysis and computer simulations in order to understand the dynamics of COVID-19 transmission. Initially, mathematical analysis of the model has been carried out in broadly by illustrating some well-known methods including exactness, equilibrium and stability analysis in terms of basic reproduction number. We investigate the sensitivity of the model with respect to the variation of the parameters' values. Furthermore, computer simulations are performed to illustrate the results. Our analysis reveals that the death rate from coronavirus disease increases as the infection rate increases, whereas infection rate extensively decreases with the increase of quarantined individuals. The quarantined individuals also lead to increase the concentration of recovered individuals. However, the infection rate of COVID-19 increases more surprisingly as the rate of asymptomatic individuals increases than that of the symptomatic individuals. Moreover, the infection rate decreases significantly due to increase of self-immunity rate. [ABSTRACT FROM AUTHOR]

Mass-balanced models were constructed for pre and post fishing ban period to compare the possible impacts of the introduction of the fishing closure management practice on the reservoir resources through estimating the trophic status and energy flow. The decreased biomass of high value fishes (Carps, Sheatfishes, Tilapia, Anabas testudineus and Knife fishes) despite the implementation of fishing closure pinpoints the excessive fishing pressure on these target species. However, the increased biomass of minnows and clupeids may pose a serious threat to reservoir stability and sustainability altering the trophic structure. Mixed trophic impact indicates that functional groups at the lower trophic level had positive effect on most of the groups. The ratio of primary production/respiration was 13.154 and 1.969 during pre-ban and post-ban season respectively. The relative overhead increased (22.48%) while ascendancy was found to be lower (-0.43%) during the post-ban period. The reservoir was more vulnerable to disruptions before the implementation of fishing ban. Some ecosystem attributes such as TPP/TB, TB/TST, TPP/TR, TPP - TR reveal that the Kaptai reservoir gained higher resilience, stability, maturity and complexity in food web after discontinuing the unlimited fishing access but it still requires attention to overcome the stresses associated with human activities. [ABSTRACT FROM AUTHOR]

In response to intramammary infection (IMI), blood-derived leukocytes are transferred into milk, which can be measured as an increase of somatic cell count (SCC). Additionally, pathogen-dependent IgG increases in milk following infection. The IgG transfer into milk is associated with the opening of the blood-milk barrier, which is much more pronounced during gram-negative than gram-positive IMI. Thus, milk IgG concentration may help to predict the pathogen type causing IMI. Likewise, lactate dehydrogenase (LDH) and serum albumin (SA) cross the blood-milk barrier with IgG if its integrity is reduced. Because exact IgG analysis is complicated and difficult to automate, LDH activity and SA concentration aid as markers to predict the IgG transfer into milk in automatic milking systems (AMS). This study was conducted to test the hypothesis that LDH and SA in milk correlate with the IgG transfer, and in combination with SCC these factors allow the differentiation between gram-positive and gram-negative IMI or even more precisely the infection-causing pathogen. Further, the expression of these parameters in foremilk before (BME) and after (AME) milk ejection was tested. In the AMS, quarter milk samples (n = 686) from 48 Holstein-Friesian cows were collected manually BME and AME, followed by an aseptic sample for bacteriological culture. Mixed models were used to (1) predict the concentration of IgG transmitted from blood into milk based on LDH and SA; (2) use principal component analysis to evaluate joint patterns of SCC (cells/mL), IgG (mg/mL), LDH (U/L), and SA (mg/mL) and use the principal component scores to compare gram-positive, gram-negative, and control IMI types and BME versus AME samples; and (3) predict gram-positive and gram-negative IMI by inclusion of combined SCC-LDH and SCC-SA as predictors in the model. Overall, the SA and LDH had similar ability to predict IgG transmission from blood into milk. Comparing the areas under the curve (AUC) of the receiver operator characteristic curves, the SCC-LDH versus SCC-SA had lower gram-positive (AUC = 0.984 vs. 0.986) but similar gram-negative (AUC = 0.995 vs. 0.998) IMI prediction ability. The SCC, IgG, LDH, and SA were greater in gram-negative than in gram-positive IMI (BME and AME) in early lactation. All measured factors had higher values in milk samples taken BME than AME. In conclusion, LDH and SA could be used as replacement markers to indicate the presence of IgG transfer from blood into milk; in combination with SCC, both SA and LDH are suitable for differentiating IMI type, and BME is better for mastitis detection in AMS. [ABSTRACT FROM AUTHOR]

A theoretical examination of electron conductance in a quantum structure having an infinite strength rectangular potential barrier, is presented. The structure comprises a quantum wire linked to a stub and a constriction. Resonance and antiresonance peaks on conductance plateaus were produced by multiple reflection of the electron waves from the stub and scatterer.The potential barrier was scanned across the width of the stub to investigated electron conductance through the stub-constriction structure.

In this research, the ability of the leaf extract of Justicia adhatoda is observed as a unique reducing agent for bioconversion of copper ions to copper oxide nanoparticles (CuO NPs). CuO NPs have significant antibacterial activity and nontoxicity toward humans. The formation of nanoparticles is confirmed by the color change of the solution from light blue to brown because of the trouble of surface plasmon resonance (SPR). The optical study showed an SPR peak at 280 nm. The interaction of CuO NPs excipients with the biomolecules is studied using x-ray diffraction and particle size is also calculated. Field emission scanning electron microscopy has been applied to recognize the size, shape, and morphology of nanoparticles, which is incorporated in cotton. Fourier transform infrared spectroscopy showed that the reduction of CuO NPs was due to the biomolecules present in the leaf extract, which acted as reducing, in addition to capping, agents. The synthesized CuO NPs-coated cotton were tested for antibacterial activity to both gram-positive and gram-negative bacterial strains, which are applicable for the fabrication of an antibacterial cotton textile. [ABSTRACT FROM AUTHOR]

We utilize the modified Riemann–Liouville derivative sense to develop careful arrangements of time-fractional simplified modified Camassa–Holm (MCH) equations and generalized (3 + 1)-dimensional time-fractional Camassa–Holm–Kadomtsev–Petviashvili (gCH-KP) through the potential double G ′ / G , 1 / G -expansion method (DEM). The mentioned equations describe the role of dispersion in the formation of patterns in liquid drops ensued in plasma physics, optical fibers, fluid flow, fission and fusion phenomena, acoustics, control theory, viscoelasticity, and so on. A generalized fractional complex transformation is appropriately used to change this equation to an ordinary differential equation; thus, many precise logical arrangements are acquired with all the freer parameters. At the point when these free parameters are taken as specific values, the traveling wave solutions are transformed into solitary wave solutions expressed by the hyperbolic, the trigonometric, and the rational functions. The physical significance of the obtained solutions for the definite values of the associated parameters is analyzed graphically with 2D, 3D, and contour format. Scores of solitary wave solutions are obtained such as kink type, periodic wave, singular kink, dark solitons, bright-dark solitons, and some other solitary wave solutions. It is clear to scrutinize that the suggested scheme is a reliable, competent, and straightforward mathematical tool to discover closed form traveling wave solutions. [ABSTRACT FROM AUTHOR]