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We report direct measurements of the magnetic field screening at the limits of the Meissner phase for two superconducting niobium (Nb) samples. The samples are processed with two different surface treatments that have been developed for superconducting radio-frequency (SRF) cavity applications—a "baseline" treatment and an oxygen-doping ("O-doping") treatment. The measurements show: (1) that the screening length is significantly longer in the "O-doping" sample compared to the "baseline" sample; (2) that the screening length near the limits of the Meissner phase increases with applied field; (3) the evolution of the screening profile as the material transitions from the Meissner phase to the mixed phase; and (4) a demonstration of the absence of any screening profile for the highest applied field, indicative of the full flux entering the sample. Measurements are performed utilizing the β -detected nuclear magnetic resonance (β -NMR) technique that allows depth resolved studies of the local magnetic field within the first 100 nm of the surface. The study takes advantage of the β -SRF beamline, a new facility at TRIUMF, Canada, where field levels up to 200 mT are available parallel to the sample surface to replicate radio frequency fields near the Meissner breakdown limits of Nb. [ABSTRACT FROM AUTHOR]

Dengue fever is an intense feverish virus related disease dispatched with the nibble of Aedes mosquitoes carrying one of the four serotypes, which are symbolized as DEN-1, DEN-2, DEN-3, DEN-4. Almost fifty two percent people of our planet is at risk due to the dengue fever. Particularly, people of the tropical and subtropical countries as like Bangladesh, India, Pakistan, Nepal, Bhutan, Malaysia, etc. are in very risky position due to this fever. In Bangladesh, dengue fever happens nationally and has been endemic for more than two decades. Therefore, for realizing the dynamical conduct of this fever a perfect scientific model of disease transmission plays a noteworthy role and help us to prevent this disease effectively. From this context, in this article a novel six compartmental ASIR dengue transmission model have been established by using conformable fractional order derivatives. In the proposed model, the dynamics of human and mosquito populations have been constructed with six compartments. Here, the analytical stability of equilibria has been shown by disease free and endemic equilibrium points. Furthermore, a sensitivity analysis of the proposed model has been executed to evaluate the comparative rank of the model parameters for dengue transmission. The data of infected human population has been accumulated from different health institutions of Bangladesh which have been used to compute the infection rate of dengue cases in Bangladesh. Finally, a numerical simulation has been constructed for studying the dynamical behavior of dengue transmission with the help of Conformable fractional differential transformation technique. [ABSTRACT FROM AUTHOR]

Mapping potential changes in bioclimatic characteristics are critical for planning mitigation goals and climate change adaptation. Assessment of such changes is particularly important for Southeast Asia (SEA) — home to global largest ecological diversity. Twenty-three global climate models (GCMs) of Coupled Model Intercomparison Project Phase 6 (CMIP6) were used in this study to evaluate changes in 11 thermal bioclimatic indicators over SEA for two shared socioeconomic pathways (SSPs), 2–4.5 and 5–8.5. Spatial changes in the ensemble mean, 5th, and 95th percentile of each indicator for near (2020–2059) and far (2060–2099) periods were examined in order to understand temporal changes and associated uncertainty. The results indicated large spatial heterogeneity and temporal variability in projected changes of bioclimatic indicators. A higher change was projected for mainland SEA in the far future and less in maritime region during the near future. At the same time, uncertainty in the projected bioclimatic indices was higher for mainland than maritime SEA. Analysis of mean multi-model ensemble revealed a change in mean temperature ranged from − 0.71 to 3.23 °C in near and from 0.00 to 4.07 °C in far futures. The diurnal temperature range was projected to reduce over most of SEA (ranging from − 1.1 to − 2.0 °C), while isothermality is likely to decrease from − 1.1 to − 4.6%. A decrease in isothermality along with narrowing of seasonality indicated a possible shift in climate, particularly in the north of mainland SEA. Maximum temperature in the warmest month/quarter was projected to increase a little more than the coldest month/quarter and the mean temperature in the driest month to increase more than the wettest month. This would cause an increase in the annual temperature range in the future. [ABSTRACT FROM AUTHOR]

Casein microparticles obtained from casein micelles by volume exclusion of added pectin and subsequent film drying remain stable in the acidic and neutral pH range, but swell strongly in the basic range. Calcium significantly impacts on the stability and water-binding behavior of phosphorylated caseins and the aggregates and gels formed from them. For a future effective and controlled use as a carrier for bioactive substances, e.g. via the gastrointestinal tract, we therefore investigated how the addition of the calcium chelating agent citrate affects the swelling and stability of the microparticles. Citrate concentrations of 2 mM and above cause a stronger swelling of the microparticles at pH 8, while above 4 mM the second characteristic swelling step starts earlier and thus can also be investigated within the observation time of 120 min. All swelling kinetics can be simulated using seven parameters of a dynamic model, which reproduces the individual swelling steps via volume inflows and outflows into a reservoir. While the rate coefficient for swelling step 1 increases linearly with citrate concentration, no such dependence could be found for swelling step 2. The more citrate is used, the faster the microparticles decompose in turbidity experiments after the addition of sodium dodecyl sulfate, which can be related to a weakening of the hydrophobic interactions. [ABSTRACT FROM AUTHOR]

The freshwater climbing perch, Anabas testudineus, is an economically and nutritionally valuable food fish. This study explores the various reproductive contents (size at sexual maturity, reproductive period and fecundity) of A. testudineus in the Gajner Beel concerning the eco-climatic variabilities and suggests sustainable management policies. A total of 709 individuals were randomly collected from January to December 2019 among 371 females that were sorted out for this study. Total length (TL) ranged from 7.50 to 16.40 cm. Based on the maximum length (Lmax), TL vs. gonadosomatic index (GSI), TL-standard length (SL) regression and logistic model, the size at sexual maturity (Lm) was 10.00 cm, 10.40 cm, 11.00 cm and 11.50 cm, respectively. The spawning season was May to August and peaked in June–July. The Fulton's condition (KF) was suggested as the best condition factor (p < 0.0001), and relative weight (WR) showed no significant difference from 100 for females (p = 0.143). Fecundity was ranged from 9459 to 35,915. A significant relationship was observed between GSI and temperature (p = 0.0016), dissolved oxygen (DO) (p < 0.0001), pH (p < 0.0001), alkalinity (p < 0.001) and climatic parameters (air temperature, p < 0.001 and rainfall, p < 0.001). The data series of 48 years (1971–2019) revealed that the rise of average air temperature by 0.029 °C and the reduction of rainfall by 2.96 mm per year might shift the spawning season of A. testudineus 15–20 later. Therefore, this study will be helpful for the sustainable management and conservation of the wild stocks of A. testudineus in the Gajner Beel and adjoining ecosystems. [ABSTRACT FROM AUTHOR]

A high-resolution (1 km × 1 km) monthly gridded rainfall data product during 1901–2018, named Bangladesh Gridded Rainfall (BDGR), was developed in this study. In-situ rainfall observations retrieved from a number of sources, including national organizations and undigitized data from the colonial era, were used. Leave-one-out cross-validation was used to assess product's ability to capture spatial and temporal variability. The results revealed spatial variability of the percentage bias (PBIAS) in the range of −2 to 2%, normalized root mean square error (NRMSE) <20%, and correlation coefficient (R2) >0.88 at most of the locations. The temporal variability in mean PBIAS for 1901–2018 was in the range of −4.5 to 4.3%, NRMSE between 9 and 19% and R2 in the range of 0.87 to 0.95. The BDGR also showed its capability in replicating temporal patterns and trends of observed rainfall with greater accuracy. The product can provide reliable insights regarding various hydrometeorological issues, including historical floods, droughts, and groundwater recharge for a well-recognized global climate hotspot, Bangladesh. Measurement(s) water-based rainfall Technology Type(s) weather station [ABSTRACT FROM AUTHOR]

Due to the dramatic increase of spectrum demand, efficient usage of the limited spectrum resources has become a crucial issue for the next-generation wireless networks. Auction-based spectrum trading, utilization and pricing have many promising features and have proven to be a fair and consistent way of secondary spectrum trading and management. In this paper, we present a mathematical approach to the future spectrum market where multiple buyers (secondary network operator) compete to gain spectrum resources through a number of auctions from multiple sellers (primary network operator, PNO). Through static and dynamic auctions, the secondary network operators borrow underutilized licensed spectrum resources from primary operators either through predefined contracts or through instantaneous contracts. Our main focus is on the optimal choice of the secondary operator, contiguous spectrum resource to maintain the quality and utilization history based fair allocation of the spectrum resources through auctions controlled by the third party spectrum regulators (SR), which has not been addressed previously. We first develop a matching problem to identify the most suitable auctions for secondary operators. A price-based optimal number of auctions and a utility-based ranking of the optimal auctions to be bid by the secondary operators are proposed, where the secondary operator maximizes the net utility surplus (NUS). The win or lose, pricing and allocation of spectrum resources are determined by a proposed Vickery-type mechanism. Finally, we provide simulation results to evaluate the performance of the proposed auction mechanism. [ABSTRACT FROM AUTHOR]

Herbicide resistance in weeds necessitates the continued monitoring of herbicide resistance evolution in weed species. This study investigated the level of paraquat resistance in two species of Conyza including Conyza sumatrensis (Retz.) E. Walker (tall fleabane) and Conyza bonariensis (L.) Cronquist (flaxleaf fleabane). Twenty-two biotypes of C. bonariensis and three biotypes of C. sumatrensis were screened for paraquat resistance evaluation. All tested biotypes of C. bonariensis were susceptible to paraquat at the recommended rate of 500 g a.i./ha. Whole plant dose–response assays showed that the two biotypes (TF-COLEA and TF-NANDI) of C. sumatrensis are resistant to the herbicide paraquat, with a ED50 more than fourfold that of the susceptible biotype (TF-TALWD). The two resistant biotypes also showed a hormetic growth increase at two lower doses (62.5 and 125 g a.i./ha) of paraquat, resulting in 31% and 17% higher biomass production at 62.5 g a.i./ha of paraquat, and 19% and 11% at 125 g a.i./ha of paraquat for the resistant biotypes TF-NANDI and TF-COLEA, respectively, than those of the untreated control. The two resistant biotypes at the two lower doses of paraquat generated 33% to 65% higher numbers of seed buds/plant in TF-COLEA and 40% to 68% in TF-NANDI compared to the untreated control. Such stimulatory responses to lower rates of paraquat can enhance the competitiveness of these resistant plants against neighboring weed and crop plants, potentially increasing the seedbank size of resistant biotypes. [ABSTRACT FROM AUTHOR]

Understanding the fate of heterogenous herbicide resistant weed populations in response to management practices can help towards overcoming the resistance issues. We selected one pair of susceptible (S) and resistant (R) phenotypes (2B21-R vs 2B21-S and 2B37-R vs 2B37-S) separately from two glyphosate resistant heterogeneous populations (2B21 and 2B37) of Echinochloa colona and their fate and adaptive plasticity were evaluated after glyphosate application. Our study revealed the glyphosate concentration required to cause a 50% plant mortality (LD50) was 1187, 200, 3064, and 192 g a. e. ha−1 for the four phenotypes 2B21-R, 2B21-S, 2B37-R, and 2B37-S respectively. Both S phenotypes accumulated more biomass than the R phenotypes at the lower application rates (34 and 67.5 g a. e. ha−1) of glyphosate. However, the R phenotypes generally produced more biomass at rates of glyphosate higher than 100 g a. e. ha−1 throughout the growth period. Plants from the R phenotypes of 2B21 and 2B37 generated 32% and 38% fewer spikesplant−1 than their respective S counterparts in the absence of glyphosate respectively. The spike and seed numbersplant-1 significantly higher in R than S phenotypes at increased rates of glyphosate and these relationships were significant. Our research suggests that glyphosate-resistant E. colona plants will be less fit than susceptible plants (from the same population) in the absence of glyphosate. But in the presence of glyphosate, the R plants may eventually dominate in the field. The use of glyphosate is widespread in field, would favour the selection towards resistant individuals. [ABSTRACT FROM AUTHOR]

Accurate representation of precipitation over time and space is vital for hydro-climatic studies. Appropriate selection of gridded precipitation data (GPD) is important for regions where long-term in situ records are unavailable and gauging stations are sparse. This study was an attempt to identify the best GPD for the data-poor Amu Darya River basin, a major source of freshwater in Central Asia. The performance of seven GPDs and 55 precipitation gauge locations was assessed. A novel algorithm, based on the integration of a compromise programming index (CPI) and a global performance index (GPI) as part of a multi-criteria group decision-making (MCGDM) method, was employed to evaluate the performance of the GPDs. The CPI and GPI were estimated using six statistical indices representing the degree of similarity between in situ and GPD properties. The results indicated a great degree of variability and inconsistency in the performance of the different GPDs. The CPI ranked the Climate Prediction Center (CPC) precipitation as the best product for 20 out of 55 stations analysed, followed by the Princeton University Global Meteorological Forcing (PGF) and Climate Hazards Group Infrared Precipitation with Station (CHIRPS). Conversely, GPI ranked the CPC product the best product for 25 of the stations, followed by PGF and CHRIPS. Integration of CPI and GPI ranking through MCGDM revealed that the CPC was the best precipitation product for the Amu River basin. The performance of PGF was also closely aligned with that of CPC. [ABSTRACT FROM AUTHOR]

The effect of milk pH before heating on casein–whey protein interactions and ultimate gel properties of the free-fat yoghurt was investigated. Reconstituted skim milk at different pH values (6.4, 6.8 and 7.2) was heated at 80 °C for 30 min. The type of protein and size of casein micelle in milk were determined. The storage modulus (G′), loss tangent (tan δ), flow behaviour as well as microstructure, firmness and water holding capacity of the yoghurt samples were measured. Heating milk at pH 7.2 formed mostly soluble protein complexes whereas at pH 6.4 micelle bound complexes was dominant. However, heating milk at pH 6.8 resulted in a relatively compact protein network due to a balanced contribution from both soluble protein/κ-casein complexes and whey protein-casein micelle associated complexes. Yoghurt prepared with milk heated at pH 6.8 showed significantly higher G′ values, shorter gelation times, higher water holding capacity, firmness and more compact protein network compared to those at pH 6.4, 7.2 and unheated milk. The obtained results demonstrated that milk pH adjustment before heating could be an important factor governing uniform quality yoghurt production. [ABSTRACT FROM AUTHOR]

Obesity is a global health concern because of its increasing trend both in developed and developing countries. A limited number of studies have evaluated the association of liver enzymes with both general and abdominal obesity in the general population; data for the Bangladeshi population are not available yet. This study aimed to assess the relationship of serum liver enzymes activity with both general and abdominal obesity in Bangladeshi adults. In total, 540 blood samples were obtained from the participants (388 males and 152 females) and analyzed for serum levels of ALT, AST, GGT, and ALP using standard methods. General obesity was defined as body mass index (BMI) ≥ 27.5 kg/m2 and abdominal obesity was defined as waist circumference (WC) ≥ 90 cm in males and ≥ 80 cm in females. The relationship between liver enzymes and obesity was evaluated by multivariate logistic regression models. Overall, 58% of participants in the general obesity group and 55% of the participants in the abdominal obesity group had at least one or more elevated levels of liver enzymes. The prevalence of elevated liver enzymes was significantly higher in the obesity group compared to the normal BMI and WC groups (p < 0.05 for all cases). The mean level of serum ALT, AST and GGT were significantly higher in the obesity group than the normal BMI group (p < 0.05). In the WC groups, mean AST and GGT were significantly higher in the obesity group compared to the normal group (p < 0.05). In regression analysis, serum levels of ALT showed an independent and significant association with general obesity, whereas, serum GGT showed a significant association with both general and abdominal obesity. In conclusion, a high prevalence of elevated liver enzymes was observed among participants included in the present study. Of the four enzymes, serum GGT was independently associated with both general and abdominal obesity. Further studies are required to understand the complex relationship between liver enzymes and obesity in the general population. [ABSTRACT FROM AUTHOR]

In this paper, we introduce and study a modified multi-step Noor iterative procedure with errors for two Lipschitz strictly hemicontractive-type mappings in arbitrary Banach spaces and constitute its convergence and stability. The obtained results in this paper generalize and extend the corresponding result of Hussain et al. (Fixed Point Theory Appl. 2012:160, 2012) and some analogous results of several authors in the literature. Finally, a numerical example is included to illustrate our analytical results and to display the efficiency of our proposed novel iterative procedure with errors. [ABSTRACT FROM AUTHOR]

Fresh-cut lettuce is a very well-known salad for today's routines because it obliges minimal preparation to minimize the loss of health beneficial vitamins, minerals, antioxidants and other phytochemicals. It is a prodigious challenge to serve its consumers fresh. Quality of freshly processed lettuce under high CO2 modified atmosphere packaging (MAP) has been investigated as a realistic alternative technique for its preservation. Storage under high CO2 atmospheric treatments exhibited a significant impact in microbial development, electrolyte leakage, volatile metabolites and sensory quality of fresh-cut iceberg lettuce. This storage condition (MAP 1: 5 kPa O2 and 20 kPa CO2 balanced by N2 at 7 °C for 6 days) inhibited the growth of mesophilic bacteria and yeasts; delayed the enzymatic browning (cut-edges and intact surface) of fresh-cut iceberg lettuce and overall visual quality was also in acceptance limit. The development of off-odors was perceived in high CO2 MAP as a consequence of volatiles (ethanol and acetaldehyde) accumulation which was persisted at an inexcusable level during 6 days of storage periods. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is a progressive neurodegenerative disorder, and the most predominant cause of dementia in the elderly. Traditionally Anisomeles indica (L.) Kuntze has widely been used as tonic to brain. Our aim is to investigate the cholinesterase inhibitory activities, and antioxidant properties of the plant extracts in the treatment of AD. The crude methanol extract was prepared by cold extraction method and four fractions namely petroleum ether, chloroform, ethyl acetate, and water fraction were assessed for acetylcholinesterase and butyrylcholinesterase inhibitory activity by the Ellman method, and their antioxidant properties were assessed by several assays including reducing power, scavenging of DPPH and hydroxyl radicals together with quantitative analyses of endogenous substances. Among the tested samples, ethyl acetate extract was found to demonstrate the highest inhibitory activity significantly against both acetylcholinesterase and butyrylcholinesterase enzymes with IC50 values of 176.02 and 143.78 mg/ml, respectively. Similarly, ethyl acetate extract exhibited the highest radical scavenging ability appeared to be comparable to the reference standard catechin used in this study. The IC50 values of the extract against DPPH and hydroxyl radical scavenging activity were 12.67 and 18.61 mg/ml respectively. Quantitative analyses displayed higher contents of phenolics and flavonoids (79.55 and 347.19 mg gallic acid equivalent/g dried extract respectively) in the ethyl acetate fraction. The results revealed that the ethyl acetate extract, possibly due to its phenolic compounds, exerts potential antioxidant and cholinesterase inhibitory activities which may be useful in the treatment of AD. [ABSTRACT FROM AUTHOR]

Crop allelopathy provides a viable alternative in managing resistant weed populations. A successful demonstration of an allelopathic interaction is needed to be separated from resource competition. A reliable laboratory screening technique can test this chemical interaction between a donor and a receiver species. However, the standardization of any screening tactic for a new species is really challenging. In this study we optimized the simple root exudates bioassay, Equal Compartment Agar Method (ECAM), for canola through basic features including sowing patterns, density, and distance between canola and annual ryegrass. We established that all of the above features have major roles on canola seedling interference ability (allelopathy + competition). Due to the combined effect of allelopathy and competition, the zigzag canola sowing pattern enhanced the inhibitory effects of canola seedlings more than other sowing patterns, i.e. circular, parallel, and cone. The sowing distance of canola played a major role on root growth of annual ryegrass in that the nearer the receiver annual ryegrass plants to the donor canola seedlings, the greater were the toxic effects. Canola sowing distance at 1, 2, and 3 cm inhibited the root growth of ryegrass by 50, 46, and 36%, respectively. Results also showed that root growth of ryegrass decreased with increased canola densities (0-40 seedlings/beaker). Furthermore, the added carbon experiment showed that the inhibitory effects of canola were diluted by added carbon in agar growth medium, indicating canola root exudates acted directly on the root growth of annual ryegrass. This study suggests parameters such as canola sowing pattern, density, and sowing distance between canola and test weed species need to be considered for designing canola allelopathy bioassay through ECAM under laboratory conditions. [ABSTRACT FROM AUTHOR]

In this paper, we consider a Markov renewal process (MRP) to model tropical cyclones occurred in Bangladesh during 1877-2009. The model takes into account both the occurrence history and some physical constraints to capture the main physical characteristics of the storm surge process. We assume that the sequence of cyclones constitutes a Markov chain, and sojourn times follow a Weibull distribution. The parameters of the Weibull MRP jointly with transition probabilities are estimated using the maximum likelihood method. The model shows a good fit with the real events, and probabilities of occurrence of different types of cyclones are calculated for various lengths of time interval using the model. Stationary probabilities and mean recurrence times are also calculated. A brief comparison with a Poisson model and a marked Poisson model has also been demonstrated. [ABSTRACT FROM AUTHOR]

MYH14 ( MYH7b) is the most recently identified sarcomeric myosin heavy chain gene ( MYH) from the human genome. Recent observations have revealed that MYH, a torafugu orthologue of MYH14, is one of the major components of the MYH repertoire expressed in torafugu embryos and adults, suggesting its pivotal role in fish muscle formation. We have examined the expression pattern of MYH14 in zebrafish, a model organism for the study of vertebrate development. In situ hybridization studies revealed that zebrafish MYH14 was expressed in the most myotomal region containing fast muscle fibers in the embryonic stage and in superficial slow muscle fibers in the adult stage. Weak signals of MYH14 transcripts were also detected in intermediate muscle fibers located between superficial slow and inner fast muscle fibers in the adult. Reverse transcription-PCR studies showed that MYH14 was not only expressed in skeletal muscles but also in cardiac muscles. These expression patterns are in a marked contrast to that of torafugu MYH, which is solely expressed in slow and cardiac muscle fibers in both the embryonic and adult stages. Our results imply species-specific functions of MYH14 in fish muscle formation. [ABSTRACT FROM AUTHOR]

The main aim of this paper is to derive a solution to the capacity problem faced by many perinatal networks in the United Kingdom. We propose a queueing model to determine the number of cots at all care units for any desired overflow and rejection probability in a neonatal unit. The model formulation is developed, being motivated by overflow models in telecommunication systems. Exact expressions for the overflow and rejection probabilities are derived. The model is then applied to a neonatal unit of a perinatal network in the UK. [ABSTRACT FROM AUTHOR]

The anadromous Hilsa shad (Tenualosa ilisha) live in the Bay of Bengal and migrate to the estuaries and freshwater rivers for spawning and nursing of the juveniles. This has led to two pertinent questions: (i) do all Hilsa shad that migrate from marine to freshwater rivers come from the same population? and (ii) is there any relationship between adults and juveniles of a particular habitat? To address these questions, NextRAD sequencing was applied to genotype 31,276 single nucleotide polymorphism (SNP) loci for 180 individuals collected from six strategic locations of riverine, estuarine and marine habitats. FST OutFLANK approach identified 14,815 SNP loci as putatively neutral and 79 SNP loci as putatively adaptive. We observed that divergent local adaptations in differing environmental habitats have divided Hilsa shad into three genetically structured ecotypes: turbid freshwater (Western Riverine), clear freshwater (Eastern Riverine) and brackish-saline (Southern Estuarine-Marine). Our results also revealed that genes involved in neuronal activity may have facilitated the juveniles' Hilsa shad in returning to their respective natal rivers for spawning. This study emphasized the application of fundamental population genomics information in strategizing conservation and management of anadromous fish such as Hilsa shad that intersect diverse ecotypes during their life-history stages. [ABSTRACT FROM AUTHOR]