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In this paper, a new metamaterial absorber (MMA) is presented that exhibits resonances at 3.5 GHz and 13 GHz having peak absorption of 92.7% and 99.99% respectively. The MMA consists of an FR4 substrate with three interconnected circular rings and disk-shaped metallic layers at the top and full copper at the back. The overall dimension is 0.14λ0 × 0.14λ0, where λ0 is calculated at 3.5 GHz. The design is optimized through numerical simulation performed in CST microwave studio. The MMA shows polarization angle and incident angle insensitivity up to 60° for both transverse electric and transverse magnetic waves. The equivalent circuit is modeled and verified through simulation in Advanced Design Software (ADS). It exhibits an almost zero polarization conversion ratio with a maximum value of 0.002 at 13 GHz. The prototype of the MMA is developed and the measured result shows good similarity with the simulation. Due to polarization and incident angle intensity, and good absorption, this compact MMA can be applied in wireless communication systems including wave shielding from 5G signals, and microwave sensing. [ABSTRACT FROM AUTHOR]

Aqueous solution containing different concentration (0.5, 0.6 and 1.0%) (w/v) of Polyvinyl pyrrolodon-Iodine (PVP-I) complex, a well-known antiseptic; is prepared and the stability and homogeneity of these solution is assessed as per the ICH Guidelines and International Harmonized Protocol respectively. The solutions were found to be sufficiently homogeneous and stable for a year at 25 °C (60%RH). Measurement uncertainty of the prepared PVP-I solutions were estimated by identifying possible sources of uncertainty using Ishikawa diagram and preparing uncertainty budget based on scope of calibration laboratory. The stable and homogenized PVP-I solution is to be used in a clinical trial for the application on oro and nasopharynx against novel SARS-CoV-2 Virus. [ABSTRACT FROM AUTHOR]

In this paper, a new metamaterial absorber (MMA) is presented that exhibits peak absorptions at 3.26 GHz, 11.6 GHz, and 17.13 GHz within S, X, and Ku bands. The unit cell of the proposed MMA is constructed on an FR4 substrate having an electrical dimension of 0.144λ × 0.144λ, where wavelength, λ is calculated at the lowest absorption frequency. The unique structural design of the unit cell consists of two concentric copper rings with which dumbbell-shaped structures are attached. The rotating symmetrical structural design of this MMA provides around 93.8%, 96.47%, and 99.95% peak absorptance in the mentioned frequencies, which is invariable with the change of incident angle as well as polarization angle. The metamaterial properties of the proposed absorber are studied along with the surface current analysis. The MMA shows single negative behaviour and it also exhibits high-quality factors (Q factor) of 21.73, 41.42, and 51.90 at maximum absorptance frequencies. The MMA is analysed by it's equivalent circuit to understand the resonance phenomenon, which is verified through simulation in Advanced Design Systems (ADS) software. The testing is done on the developed prototype of the proposed MMA. Measurement results are in close proximity to the simulation results. Due to its high Q factor, high EMR, and insensitivity to polarization and angle of incidence, it can be utilized as a part of miniaturized microwave device. In addition, the proposed MMA can exhibit high sensing performance and flexibility to differentiate different oils in S, X, and Ku bands. [ABSTRACT FROM AUTHOR]

Purpose: Inflammation is thought to play a key role in malignant disease and may play a significant part in the expression of cancer-related symptoms. Cannabidiol (CBD) is a bioactive compound in cannabis and is reported to have significant anti-inflammatory properties. Method: Serial C-reactive protein (CRP) levels were measured in all participants recruited to a randomised controlled trial of CBD versus placebo in patients with symptoms related to advanced cancer. A panel of inflammatory cytokines was measured over time in a subset of these patients. Results: There was no difference between the two arms in the trajectory of CRP or cytokine levels from baseline to day 28. Conclusion: We were unable to demonstrate an anti-inflammatory effect of CBD in cancer patients. Trial registration: ANZCTR 26180001220257, registered 20/07/2018. [ABSTRACT FROM AUTHOR]

In this article, a unique metamaterial (MTM) structure is presented that exhibits four resonances of transmission coefficient (S21) that fall into S, X, and Ku bands. The MTM design is initiated on a Rogers (RT5880) substrate with an electrical dimension of 0.088 λ × 0.088 λ (λ is calculated at 3.424 GHz). The resonating patch contains four quartiles connected by a central metallic strip. The placement of each quartile is such that the whole resonator is mirror symmetric about the vertical axis. Two H-shaped modifiers connect two quartiles of each vertical half of the resonator. These H-shaped modifiers form the resonance cavity in its vicinity, and thus help significantly to orient the overall resonances of the proposed MTM at 3.424 GHz, 10 GHz, 14.816 GHz, and 16.848 GHz. The resonance phenomena are examined through equivalent circuit modeling and verified in Advanced Design Software (ADS). Metamaterial properties of the proposed MTM are extracted and it exhibits negative permittivity, permeability, and refractive index. The prototype of the MTM is fabricated and measurement is taken. The measured S21 shows a close similarity with the simulated result. Moreover, effective medium ratio (EMR) is calculated for the proposed MTM and a high EMR of 10.95 is obtained that expresses its compactness. This compact MTM with negative permittivity, permittivity, and refractive index can be important component for improving the performance of the miniaturized devices for multi-band wireless communication systems. [ABSTRACT FROM AUTHOR]

The surface subsidence in the Krishna Godavari (KG) basin in India has increased with the discovery of crude oil and natural gas reserves since 1983. With private players coming up to bag the exploration and refining contracts, there must be timely monitoring of the surface subsidence of the region so that remedial measures for the resettlement of the populations can be taken promptly. Regular monitoring is necessary since the region is fertile and any seawater ingress results in the loss of valuable cultivable land. Multi-temporal SAR Interferometry (MTInSAR) technique has been applied successfully all over the world for the study and regular monitoring of land surface subsidence scenarios. This study utilizes data from Sentinel-1 C-band SAR sensor for MTInSAR-based surface subsidence and RADAR Vegetation Index (RVI)-based vegetation loss for the same season estimation between 2017 and 2022 for the KG basin region. It is inferred from the study that the region has shown surface subsidence of 80 mm/year between April 2020 and June 2022. This study uses support vector regressor (SVR) to predict the loss in forest cover in terms of RVI using MTInSAR-based surface subsidence, VH, and VV backscatter as parameters. It is observed that the SVR gave R2-statistics of 0.89 and 0.873 in the training and testing phases with a mean absolute error (MAE) and root mean squared error (RMSE) of 0.08 and 0.02, respectively. It is also observed that the region showed a loss of 3.21 km2 of cultivable land between 2020 and 2022. [ABSTRACT FROM AUTHOR]

Real-time Action Recognition (ActRgn) of assembly workers can timely assist manufacturers in correcting human mistakes and improving task performance. Yet, recognizing worker actions in assembly reliably is challenging because such actions are complex and fine-grained, and workers are heterogeneous. This paper proposes to create an individualized system of Convolutional Neural Networks (CNNs) for action recognition using human skeletal data. The system comprises six 1-channel CNN classifiers that each is built with one unique posture-related feature vector extracted from the time series skeletal data. Then, the six classifiers are adapted to any new worker through transfer learning and iterative boosting. After that, an individualized fusion method named Weighted Average of Selected Classifiers (WASC) integrates the adapted classifiers as an ActRgn system that outperforms its constituent classifiers. An algorithm of stream data analysis further differentiates the actions for assembly from the background and corrects misclassifications based on the temporal relationship of the actions in assembly. Compared to the CNN classifier directly built with the skeletal data, the proposed system improves the accuracy of action recognition by 28%, reaching 94% accuracy on the tested group of new workers. The study also builds a foundation for immediate extensions for adapting the ActRgn system to current workers performing new tasks and, then, to new workers performing new tasks. [ABSTRACT FROM AUTHOR]

The concentrations of eleven heavy metals (Pb, Cd, Cr, Fe, Mn, Zn, Cu, Ni, Co, As, and Ag) were assessed in both groundwater and seawater collected from the ship-breaking industrial area of Bangladesh using an atomic absorption spectrometer. The investigation aimed to estimate the water quality and pollution level employing several indices, and its associated health risks for the first time in that area. This study found that Cd, Cr, Fe, Pb, Mn, and Ni were higher in both groundwater and seawater compared with WHO standards. Based on the WQI (water quality index) and EWQI (entropy water quality index) classifications, the quality of most of the groundwater is extremely poor or unsuitable for drinking purposes. Furthermore, the HPI (heavy metal pollution index), HEI (heavy metal evaluation index), and CD (degree of contamination) values of most groundwater and all seawater samples exhibit a higher degree of pollution. In addition, the results of NI (Nemerow pollution index) come to an end that both groundwater and seawater in the study area are mostly polluted by Fe, Mn, Pb, Cr, and Cd. Although the HI (hazard quotient index) values of almost all studied heavy metals in both cases of adults and children are within the safe limit, the HI value of Cr for an adult is near the threshold limit and the maximum HI value of Cr for children exceeds this limit. The carcinogenic risk reveals that Cr, Pb, As, and Cd produce detrimental effects on local people through the direct ingestion of groundwater. The pollution source is identified using principal component analysis and a Pearson correlation matrix as being primarily anthropogenic and attributed to intensive ship-breaking activities or other industries in the area. [ABSTRACT FROM AUTHOR]

In this article, a symmetric split ring resonator (SRR) based metamaterial (MTM) is presented that exhibits three resonances of transmission coefficient (S21) covering S, C, and X-bands with epsilon negative (ENG) and near zero index properties. The proposed MTM is designed on an FR4 substrate with the copper resonator at one side formed with two square rings and one circular split ring. The two square rings are coupled together around the split gap of the outer ring, whereas two split semicircles are also coupled together near the split gaps. Thus, gap coupled symmetric SRR is formed, which helps to obtain resonances at 2.78 GHz, 7.7 GHz and 10.16 GHz with desired properties of the MTM unit cell. The MTM unit cell's symmetric nature helps reduce the mutual coupling effect among the array elements. Thus, different array of unit cells provides a similar response to the unit cell compared with numerical simulation performed in CST microwave studio and validated by measurement. The equivalent circuit is modelled for the proposed MTM unit cell in Advanced Design System (ADS) software, and circuit validation is accomplished by comparing S21 obtained in ADS with the same of CST. The effective medium ratio (EMR) of 10.7 indicates the compactness of the proposed MTM. A test antenna is designed to observe the effect of the MTM over it. Numerical analysis shows that the proposed MTM have an impact on the antenna when it is used as the superstrate and helps to increase the gain of the antenna by 95% with increased directivity. Thus, compact size, high EMR, negative permittivity, near zero permeability and refractive index makes this MTM suitable for S, C and X band applications, especially for antenna gain with directivity enhancement. [ABSTRACT FROM AUTHOR]

Long-distance, high latency teleoperation tasks are difficult, highly stressful for teleoperators, and prone to over-corrections, which can lead to loss of control. At higher latencies, or when teleoperating at higher vehicle speed, the situation becomes progressively worse. To explore potential solutions, this research work investigates two 2D visual feedback-based assistive interfaces (sliding-only and sliding-and-zooming windows) that apply simple but effective video transformations to enhance teleoperation. A teleoperation simulator that can replicate teleoperation scenarios affected by high and adjustable latency has been developed to explore the effectiveness of the proposed assistive interfaces. Three image comparison metrics have been used to fine-tune and optimise the proposed interfaces. An operator survey was conducted to evaluate and compare performance with and without the assistance. The survey has shown that a 900ms latency increases task completion time by up to 205% for an on-road and 147% for an off-road driving track. Further, the overcorrection-induced oscillations increase by up to 718% with this level of latency. The survey has shown the sliding-only video transformation reduces the task completion time by up to 25.53%, and the sliding-and-zooming transformation reduces the task completion time by up to 21.82%. The sliding-only interface reduces the oscillation count by up to 66.28%, and the sliding-and-zooming interface reduces it by up to 75.58%. The qualitative feedback from the participants also shows that both types of assistive interfaces offer better visual situational awareness, comfort, and controllability, and significantly reduce the impact of latency and intermittency on the teleoperation task. [ABSTRACT FROM AUTHOR]

Polyethene is a global environmental threat, whereas jute (Corchorus spp.) fiber is biodegradable, eco-friendly and can be used as a substitute for polyethene. Jute is a short-day plant and cultivated in March to July in Indian subcontinent for bast fiber production. This season-bound cultivation nature hampers continuous supply of bast fiber in the industry. In addition, its long cultivation period creates difficulties to accommodate other high-value crops. To address these issues, a short life span (early flowering) jute genotype is extremely felt in jute growing areas of the world. But, unfortunately such variety has not been developed yet through both conventional and biotechnological approach. Accordingly, we adopted chemical mutagenesis by establishing LD50 (Lethal Dose) of EMS (Ethyl Methane Sulfonate) at 150 mM with 4h' incubation for Capsularis jute seed. A novel mutant was found named—Komola, which showed a shorter lifespan than its ancestor by flowering at 70 days instead of 120 days. In addition, the mutant's stem and petiole was coppery-red instead of green. Molecular analysis revealed four SNPs in PMIR1 (Plastid Movement Impaired 1 Related 1) and two clade deletions in ELF3 (Early Flowering 3) genes from stable M4 generation. Histochemical and biochemical analyses explained this genotype's lower content of lignin. This mutant could be used as future breeding material for the development of year-round cultivable jute genotype along with offer up accommodation of other high-value agricultural crops in cropping pattern with a good source of year-round supply of bast fiber to the industry. [ABSTRACT FROM AUTHOR]

The variations in vegetation coverage (defined as the area with Normalised Difference Vegetation Index (NDVI) > 0.2) and atmospheric patterns occurring during various vegetation seasons in the Kabul River Basin (KRB) in Afghanistan during 2001–2019 were analyzed. The analysis was done based on the NDVI, land surface temperature (LST), precipitation images from the remote sensing data, and geopotential height and temperature at 500 hPa from the retrospective datasets. The results revealed that the vegetation dynamics in KRB are impacted by both precipitation and LST. In the winter season, the LST has a more substantial role in shaping the vegetation dynamics than precipitation, while it is on contrary during the summer season. Cluster analysis showed that the four atmospheric patterns (e.g., Sub-Tropical High Pressure (STHP), Western European ridge-the Eastern Mediterranean and the Black Sea trough, Caspian Sea ridge (CSR), and the Mediterranean Sea trough-Central to Eastern Iran trough) can be identified and connected with the periods with the highest and the lowest vegetation coverage (VC) anomalies in the study area. The CSR and the Mediterranean Sea trough-the Central to Eastern Iran trough are the patterns responsible for the most positive VC anomalies. At the same time, the STHP and Western Europe ridge-the Eastern Mediterranean and the Black Sea trough are responsible for the most negative VC anomalies. As the atmospheric patterns have a significant role in shaping the vegetation status, a quick alert system to prevent agricultural areas from water or temperature stresses can be developed based on observations of them. [ABSTRACT FROM AUTHOR]

This article presents a novel metamaterial (MTM) with a mirror symmetric resonator that exhibits multiple resonances of transmission coefficient covering the L, S, C, and X bands. The resonating patch is constructed on a low-loss Rogers (RT5880) substrate with a dimension of 20 × 20 × 1.575 mm3. It consists of four equal quartiles with each quartile made with interconnected split-ring resonators; the quartiles are in mirror symmetry with each other. The proposed MTM exhibits resonances at 1.98 GHz, 3.67 GHz, 4.74 GHz, 8.38 GHz, and 10.8 GHz, and electromagnetic characterization is performed through studies of permittivity, permeability, refractive index, and impedances. Power analysis is also performed, and the effect of polarized incident waves is studied. An electromagnetic characterization study reveals that the proposed MTM shows negative permittivity with near-zero permeability and refractive index. It also reveals very little power consumption in the vicinity of the resonances. The dielectric-based frequency tuning is studied by using different dielectric layers over the patch that provides good frequency tuning; this method provides flexibility for adjusting the resonance frequencies in accordance with the application demand. The measured result of the proposed unit cell with the dielectric layer is extracted using a vector network analyzer, and the results exhibit good similarity with the simulated ones. The above-mentioned properties, along with a good effective medium ratio (EMR) of 7.57 indicate that this MTM is suitable for frequency selective applications in microwave devices such as antenna performance improvement and sensing. [ABSTRACT FROM AUTHOR]

This paper addresses the assessment of the relation of land-use dynamics and climate change based on the relationship of land surface temperature (LST), normalised difference vegetation index (NDVI) and normalised difference built up index (NDBI) using Landsat 4, 5 TM and 8 OLI/TIRS between 1989 and 2019. In situ condition was assessed using ground observations for validating satellite-derived temperature. LST was derived using NDVI-based emissivity method which uses non-linear split-window algorithm. To establish relationship among LST, NDBI and NDVI pixel-based approach was adopted. Increase in LST was observed with an increase of impervious surface and decrease of greenery. A strong positive correlation coefficient of 0.573 (P value = 0.01) was observed between LST and NDBI for the period 1989–2019 along with a strong negative correlation between LST and NDVI (r = −0.431, P value = 0.01). The correlation of NDBI–NDVI was also moderately negative (correlation coefficient = −0.284, P value = 0.01). A section of Greater Dhaka has been identified because it showed the highest rise in LST, air temperature and impervious surface and highest decrease in vegetation and rainfall. The trend of urban increase shows that in future, areas which share their boundary with Dhaka city will experience rapid urbanisation. Those areas are also expected to experience high air and surface temperature as well. [ABSTRACT FROM AUTHOR]

This study has investigated the impact of inverse G-like shape resonators that exhibited epsilon negative (ENG) and near-zero refractive index (NZI) properties for multi-band wireless communications applications. The electrical measurement of structure is 0.118λ × 0.118λ × 0.021 λ, which is calculated at 3.94 GHz. FR-4 is used as a substrate layer, and the resonator is designed on it. This structure is manifested in the ENG and NZI characteristics within the frequency range of 3.8–4.17, 7.68–8.54, 10.67–11.36 GHz, and 4.07–4.15 and 8.29–8.37 GHz, respectively. This study also manifests the polarization insensitivity nature of 0°–90°, and the incident angle is investigated up to 60° for both TE and TM modes. The proposed structure achieves triple resonance at 3.94 GHz, 8.08 GHz, and 11.17 GHz, respectively, included in the S, C, and X frequency bands. The CST Microwave Studio 2019 software is conducted to design, develop, perform analysis, investigate electromagnetic properties, and extract effective medium parameters. The Advanced Design Software (ADS) is used to model the equivalent circuit of the unit cell. The simulated, measured, and ADS results verified the scattering parameter performance. The EMR value of the structure is 8.47, indicating the structure's compactness. The compact design with simplicity, ENG, and NZI properties make the proposed structure significant for microwave application, mainly to enhance the antenna bandwidth and gain filter design. ENG and NZI properties the operation frequency stability and efficiency for low earth orbit nanosatellite communications. [ABSTRACT FROM AUTHOR]

Wastewater management and its environment-friendly applications seem to be very complicated associated with chemical effects due to their dynamic characteristics for developing countries. Most of the world's agencies or countries have been treated wastewater using chemical coagulants which have contributed to other environmental complications. Considering the impacts of chemical coagulation, this study is novel research to identify alternative components that would be applied as a natural coagulant. The present study was conducted using two different regional clays as coagulants which were collected from Portugal and Bangladesh's Patuakhali coastal area. The clay coagulant applications were applied to investigate the removal efficiency of physical properties (turbidity), chemical properties (pH and COD), and heavy metals (Cr, Cd, Ni, and Pb) from wastewater. Comparatively, the highest removal efficiency was examined by the coastal clay of Patuakhali. This soil is also easily available in the local context and can be economically viable. [ABSTRACT FROM AUTHOR]

In this paper, a tuned metamaterial (MTM) consisting of a symmetric split ring resonator is presented that exhibits epsilon negative (ENG), near zero permeability and refractive index properties for multiband microwave applications. The proposed metamaterial is constituted on a Rogers (RT-5880) substrate with 1.57 mm thickness and the electrical dimension of 0.14λ × 0.14λ, where wavelength, λ is calculated at 4.2 GHz. The symmetric resonating patch is subdivided into four equal and similar quartiles with two interconnecting split rings in each quartile. The quartiles are connected at the center of the substrate with a square metal strip with which four tuning metal strips are attached. These tuning metal strips are acted as spacers between four quartiles of the resonator patch. Numerical simulation of the proposed design is executed in CST microwave studio. The proposed MTM provides four resonances of transmission coefficient (S21) at 4.20 GHz, 10.14 GHz, 13.15 GHz, and 17.1 GHz covering C, X and Ku bands with negative permittivity, near zero permeability and refractive index. The calculated effective medium ratio (EMR) is 7.14 at 4.2 GHz indicates its compactness. The resonance frequencies are selective in nature which can be easily tuned by varying the length of the tuning metal stubs. The equivalent circuit of the proposed MTM is modelled in Advanced Design Software (ADS) that exhibits a similar S21 compared with CST simulation. Surface current, electric and magnetic fields are analyzed to explain the frequency tuning property and other performances of the MTM. Compact size, ENG with near zero permeability and refractive index along with frequency selectivity through tuning provides flexibility for frequency selective applications of this MTM in wireless communications. [ABSTRACT FROM AUTHOR]

In this paper, a meander-lines-based epsilon negative (ENG) metamaterial (MTM) with a high effective medium ratio (EMR) and near-zero refractive index (NZI) is designed and investigated for multiband microwave applications. The metamaterial unit cell is a modification of the conventional square split-ring resonator in which the meander line concept is utilized. The meander line helps to increase the electrical length of the rings and provides strong multiple resonances within a small dimension. The unit cell of proposed MTM is initiated on a low-cost FR4 substrate of 1.5 mm thick and electrical dimension of 0.06λ × 0.06λ, where wavelength, λ is calculated at the lowest resonance frequency (2.48 GHz). The MTM provides four major resonances of transmission coefficient (S21) at 2.48, 4.28, 9.36, and 13.7 GHz covering S, C, X, and Ku bands. It shows negative permittivity, near-zero permeability, and near-zero refractive index in the vicinity of these resonances. The equivalent circuit is designed and modeled in Advanced Design System (ADS) software. The simulated S21 of the MTM unit cell is compared with the measured one and both show close similarity. The array performance of the MTM is also evaluated by using 2 × 2, 4 × 4, and 8 × 8 arrays that show close resemblance with the unit cell. The MTM offers a high effective medium ratio (EMR) of 15.1, indicating the design's compactness. The frequency hopping characteristics of the proposed MTM is investigated by open and short-circuited the three outer rings split gaps by using three switches. Eight different combinations of the switching states provide eight different sets of multiband resonances within 2–18 GHz; those give the flexibility of using the proposed MTM operating in various frequency bands. For its small dimension, NZI, high EMR, and frequency hopping characteristics through switching, this metamaterial can be utilized for multiband microwave applications, especially to enhance the gain of multiband antennas. [ABSTRACT FROM AUTHOR]

An inductively tuned modified split-ring resonator-based metamaterial (MTM) is presented in this article that provides multiple resonances covering S, C, X, and Ku-bands. The MTM is designed on an FR-4 substrate with a thickness of 1.5 mm and an electrical dimension of 0.063λ × 0.063λ where wavelength, λ is calculated at 2.38 GHz. The resonator part is a combination of three squared copper rings and one circular ring in which all the square rings are modified shaped, and the inner two rings are interconnected. The resonance frequency is tuned by adding inductive metal strips in parallel two vertical splits of the outer ring that causes a significant shift of resonances towards the lower frequencies and a highly effective medium ratio (EMR) of 15.75. Numerical simulation software CST microwave studio is used for the simulation and performance analysis of the proposed unit cell. The MTM unit cell exhibits six resonances of transmission coefficient (S21) at 2.38, 4.24, 5.98, 9.55, 12.1, and 14.34 GHz covering S, C, X, and Ku-bands with epsilon negative (ENG), near-zero permeability, and near-zero refractive index (NZI). The simulated result is validated by experiment with good agreement between them. The performance of the array of the unit cells is also investigated in both simulation and measurement. The equivalent circuit modeling has been accomplished using Advanced Design Software (ADS) that shows a similar S21 response compared to CST simulation. Noteworthy to mention that with the copper backplane, the same unit cell provides multiband absorption properties with four major absorption peaks of 99.6%, 95.7%, 99.9%, 92.7% with quality factors(Q-factor) of 28.4, 34.4, 23, and 32 at 3.98, 5.5, 11.73 and 13.47 GHz, respectively which can be applied for sensing and detecting purposes. The application of an array of the unit cells is investigated using it as a superstrate of an antenna that provides a 73% (average) increase of antenna gain. Due to its simple design, compact dimension with high EMR, ENG property with near-zero permeability, this multiband NZI metamaterial can be used for microwave applications, especially for multiband antenna gain enhancement. [ABSTRACT FROM AUTHOR]

Connecting climate-induced yield anomalies to the key climatic variables (KCVs) and large-scale atmospheric circulation index (LACI) is crucial to developing a strategic policy for food security in developing countries including Bangladesh. However, the effects of the KCVs and LACI on rice yield are still less explored in Bangladesh. This study aims to investigate daily climatic datasets from 18 sites and five LACIs during 1980–2017 to explore climate-induced yield anomalies to the KCVs and LACIs in different sub-zones of Bangladesh using the decoupling model and ensemble empirical mode decomposition (EEMD). We demarcated four sub-zones (northern, southwestern, south-central, and western) with different climate-induced yield index (CIYI) of winter Boro rice oscillations by employing principal component analysis. The CIYI time series in the northern zone was dominated by a 2–4-year oscillation, whereas the CIYI in the western zone demonstrated a prominent 6.5-year oscillation. Among the four sub-zones, south-central and northern zones had the most notable CIYI-KCV and CIYI-LACI associations, while the potential evapotranspiration (PET) in March and multivariate ENSO indices (MEI) in January were identified as the best yield prediction indicator. Wavelet coherence analysis indicated significant in-phase and out-phase coherences between KCVs and CIYI fluctuations at different time-frequency bands in these sub-zones. The random forest model also confirmed the MEI as the key driver influencing the rice yield fluctuation in Bangladesh. The isotopic signature of rainwater also demonstrated that the temperature variation is the main driver for event-based precipitation change in the south-central rice-growing zone. These outcomes can provide a scientific basis to take adaptive measures to mitigate the reduction in rice yield in western and northern Bangladesh for associated decision-makers and practitioners. [ABSTRACT FROM AUTHOR]

Profenofos is an endocrine-disrupting chemical that can enter into the aquatic ecosystem either through surface runoff or through percolation of a toxicant from the soil. In order to clarify the effect of profenofos on the developmental stages of zebrafish, the embryos were treated with serial dilutions of profenofos (0%, 10%, 25%, and 50% of LC50). Embryos were treated with profenofos for 7 days or until hatching. The toxic endpoints assessed include hatching time, survival, malformation, and heartbeats of the embryos. In a 96-h test on zebrafish embryos, the LC50 of profenofos was 0.057 mg/L. Profenofos considerably lowered survival, increased abnormalities at different ontogenetic stages, and developed malformations of different organs in a concentration-dependent fashion. The identified developmental malformations were fluid accumulation, impaired jaw, short tail, ruptured pectoral and caudal fin, curved body, thin yolk sac tube, and deformed heart. The way of looping arrangement of the heart at the early stage of embryos was significantly influenced by the higher concentration of profenofos. Heartbeat is also reduced significantly in a concentration-dependent fashion. The results show that the zebrafish are susceptible to profenofos even at lower concentrations in the initial stage. Therefore, when used in agricultural areas adjacent to the aquatic environment, endocrine-disrupting chemicals should be used in an appropriate manner. [ABSTRACT FROM AUTHOR]

This paper represents a penta band square enclosed star-shaped modified split ring resonator (SRR) based single negative meta-atom absorber (MAA) for multi-band microwave regime applications. FR-4 low-cost material has been used as a substrate to make the MAA unit cell with 0.101λ0 × 0.101λ0 of electrical size, where λ0 is the wavelength calculated at the lower resonance frequency of 3.80 GHz. There are two outer square split ring and one inner star ring shape resonator of 0.035 mm thickness of copper placed on the one side, and another side of the substrate has full copper to construct the desired unit cell. The MAA unit cell provides five absorption peaks of 97.87%, 93.65%, 92.66%, 99.95%, and 99.86% at the frequencies of 3.80, 5.65, 8.45, 10.82, and 15.92 GHz, respectively, which covers S-, C-, X-, and Ku- bands. The properties of MAA have been investigated and analyzed in the E-, H-fields and surface current. The EMR and highest Q factor of the designed MAA is 9.87 and 30.41, respectively, and it shows a single negative (SNG) property. Different types of parametric analysis have been done to show the better performance of absorption. Advanced Designed System (ADS) software has been used for equivalent circuit to verify the simulated S11 result obtained from the CST-2019 software. Experimental outcomes of the MAA unit cell have a good deal with the simulated result and measured result of the 24 × 20 array of unit cells also shown. Since the unit cell provides superior EMR, excellent Q-factor, and highest absorption so the recommended MAA can be effectively used as a penta band absorber in microwave applications, like notch filtering, sensing, reducing the unintended noise generated with the copper component of the satellite and radar antennas. [ABSTRACT FROM AUTHOR]

Background: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the etiologic agent of coronavirus disease 2019 (COVID-19), is rapidly acquiring new mutations. Analysis of these mutations is necessary for gaining knowledge regarding different aspects of therapeutic development. Previously, we have reported a Sanger method-based genome sequence of a viral isolate named SARS-CoV-2 NIB-1, circulating in Bangladesh. The genome has four novel non-synonymous mutations in V121D, V843F, A889V, and G1691C positions. Results: Using different computational tools, we have found V121D substitution has the potential to destabilize the non-structural protein-1 (NSP-1). NSP-1 inactivates the type-1 interferon-induced antiviral system. Hence, this mutant could be a basis of attenuated vaccines against SARS-CoV-2. V843F, A889V, and G1691C are all located in nonstructural protein-3 (NSP-3). G1691C can decrease the flexibility of the protein. V843F and A889V might change the binding pattern and efficacy of SARS-CoV-2 papain-like protease (PLPro) inhibitor GRL0617. V843F substitution in PLPro was the most prevalent mutation in the clinical samples. This mutation showed a reduced affinity for interferon-stimulated gene-15 protein (ISG-15) and might have an impact on innate immunity and viral spread. However, V843F+A889V double mutant exhibited the same binding affinity as wild type PLPro. A possible reason behind this phenomenon can be that V843F is a conserved residue of PLPro which damaged the protease structure, but A889V, a less conserved residue, presumably neutralized that damage. Conclusions: Mutants of NSP-1 could provide attenuated vaccines against coronavirus. Also, these mutations of PLPro might be targeted to develop better anti-SARS therapeutics. We hope our study will help to get better insides during the development of attenuated vaccine and PLPro inhibitors. [ABSTRACT FROM AUTHOR]

The Kapadak River basin in SW Bangladesh lies on late Holocene-Recent alluvium of the Ganges deltaic plain in the north and Ganges estuarine plain in the south. The anion and cation trends in the analyzed shallow-tube well and river water are C l − > H C O 3 − > N O 3 − > S O 4 2 − and Na+>K+>Ca2+>Mg2+ respectively. The groundwater of the area is of sodium-calcium cation facies and chloride-bicarbonate to carbonate- sulfate anion facies. The river water is of sodium-potassium cation facies and chloride-bicarbonate—sulphate to chloride —sulphate-bicarbonate anion facies. The shallow tube well is contaminated with arsenic which exceeds the WHO recommended value for drinking water (10 µg/l). The shallow water contains salinity above the standard which is unsuitable for drinking as well as for agricultural activities. The concentration of arsenic, sodium, calcium, potassium, chlorine, bicarbonate, percentage of salinity and specific electrical conductance decreases with increasing depth. The shallow tube well water of the study area is very saline exceeding the permissible limit and requires treatment. The deep tube-well water contains lower amount of arsenic and sodium, lower percentage of salinity and specific electrical conductance in comparison to shallow tube-well water. As a result, the deep tube-well water is free from arsenic toxicity and has low to high salinity hazard, but is also hard that exceeds the tolerable limit of hardness of groundwater for drinking, public health and agricultural purposes and requires softening. The Kapadak river water is highly concentrated with sodium, potassium, magnesium, calcium, chloride, bicarbonate, and specific electrical conductance which cause the deterioration of river water quality for agricultural purposes. According to the values of TDS, EC, boron concentration, Na%, and SAR, the shallow tube-well water as well as river water is of poor quality and unsafe for irrigation purposes, while the deep tube-well water is poorly safe for drinking and irrigation purposes. As a whole in the study area groundwater quality degrades from north to south as southern part is inundated regularly by saline estuarine water. The chemical weathering of rock-forming minerals influences the groundwater quality. Entrapped saline water in the aquifers during the Holocene time is the main source of salinity in this area with minor contribution from dissolution of halides and saline estuarine water in the Kapadak river due to tidal inundation. [ABSTRACT FROM AUTHOR]

To investigate the hydrogeochemical characteristics of groundwater 23 shallow, 30 intermediate and 38 deep wells samples were collected from Sylhet district of Bangladesh, and analyzed for temperature, pH, Eh, EC, DO, DOC, Na+, K+, Ca2+, Mg2+, Cl−, SO42−, NO3−, HCO3−, SiO2−, Fe, Mn and As. Besides, 12 surface water samples from Surma and Kushiyara Rivers were also collected and analyzed to understand the influence into aquifers. Results revealed that, most of the groundwater samples are acidic in nature, and Na–HCO3 is the dominant groundwater type. The mean value of temperature, EC, Na+, K+, Ca2+, Mg2+, Cl−, NO3− and SO42− were found within the range of permissible limits, while most of the samples exceeds the allowable limits of Fe, Mn and As concentrations. However, relatively higher concentration of Fe and Mn were found in deep water samples and reverse trend was found in case of As. The mean concentrations of As in shallow, intermediate and deep wells were 39.3, 25.3 and 21.4 µg/L respectively, which varied from 0.03 to 148 µg/L. From spatial distribution, it was found that Fe, Mn and As concentrations are high but patchy in northern, north-western, and south-western part of Sylhet region. The most influential geochemical process in study area were identified as silicate weathering, characterized by active cation exchange process and carbonate weathering, which thereby can enhance the elemental concentrations in groundwater. Pearson's correlation matrix, principal component analysis and cluster analysis were also employed to evaluate the controlling factors, and it was found that, both natural and anthropogenic sources were influencing the groundwater chemistry of the aquifers. However, surface water has no significant role to contaminate the aquifers, rather geogenic factors affecting the trace elemental contamination. Thus it is expected that, outcomes of this study will provide useful insights for future groundwater monitoring and management of the study area. [ABSTRACT FROM AUTHOR]

Physalis alkekengi var. francheti is an indigenous herb well known for its anti-inflammatory, sedative, antipyretic, and expectorant properties. However, the information regarding the impacts of P. alkekengi fruits (PAF) in modulation of oxidative stress and learning memory are still unknown. This study therefore evaluated the antioxidant properties of ethyl acetate (EA) fraction of PAF and its impacts on learning and memory. The antioxidant activities of PAF were evaluated in LPS-induced BV2 microglial cells. The potent EA fraction then investigated and confirmed for its involvement of HO-1 pathway using hemin (HO-1 inducer) and ZnPP (HO-1 inhibitor) through Western blotting, DCFH-DA, and/or Griess assay. The involvements of PI3K/Akt, MEK, and p38 MAPK also investigated. Furthermore, we applied EA fraction to the animals at 100 and 200 mg/kg doses to check if the extract could improve scopolamine-induced memory deficits in passive avoidance and elevated plus maze tests. Our results demonstrated that the fractions from PAF significantly inhibited the generation of intracellular reactive oxygen species (ROS) induced by LPS in concentration-dependent manners. In comparison to other fractions, the EA fraction exhibited potent effect in suppressing intracellular ROS generation. Besides, EA fraction also induced the expression of HO-1 in time- and concentration-dependent manners. ZnPP significantly reversed the suppressive effect of EA fraction on LPS-induced ROS generation and NO production, which confirm the involvement of HO-1 signaling in EA-fraction-mediated antioxidant activities. Consistently, blocking of PI3K/Akt, MEK, and p38 MAPK pathways by PAF-EA suppressed the production of intracellular ROS, indicating their potential participation. In addition, one of the major constituents of EA fraction, luteolin-7-O-β-D-glucoside, also demonstrated HO-1-dependent antioxidant effects in BV2 cells. Further, the EA fraction significantly (p < 0.05) improves scopolamine-induced memory deficits in mice. Taken together, our findings highlight the antioxidant effects of EA fraction of PAF which may be beneficial in treatment of different neurodegenerative diseases associated with free radicals. [ABSTRACT FROM AUTHOR]

Cell-penetrating peptides (CPPs) can translocate across the plasma membrane of living eukaryotic cells and enter the cytosol without significantly affecting cell viability. Consequently, CPPs have been used for the intracellular delivery of biological cargo such as proteins and oligonucleotides. However, the mechanisms underlying the translocation of CPPs across the plasma membrane remain unclear. In this mini-review, we summarize the experimental results regarding the entry of CPPs into lipid bilayer vesicles obtained using three methods: the large unilamellar vesicle (LUV) suspension method, the giant unilamellar vesicle (GUV) suspension method, and the single GUV method. The advantages and disadvantages of these methods are also discussed. Experimental results to date clearly indicate that CPPs can translocate across lipid bilayers and enter the vesicle lumen. Three models for the mechanisms and pathways by which CPPs translocate across lipid bilayers are described: (A) through pores induced by CPPs, (B) through transient prepores, and (C) via formation of inverted micelles. Both the pathway of translocation and the efficiency of entry of CPPs depend on the lipid composition of the bilayer and the type of CPP. We also describe the interaction of CPPs with bacterial cells. Some CPPs have strong antimicrobial activities. There are two modes of action of CPPs on bacterial cells: CPPs can induce damage to the plasma membrane and thus increase permeability, or CPPs enter the cytosol of bacterial cells without damaging the plasma membrane. The information currently available on the elementary processes by which CPPs enter lipid bilayer vesicles and bacterial cells is valuable for elucidating the mechanisms of entry of CPPs into the cytosol of various eukaryotic cells. [ABSTRACT FROM AUTHOR]

The present research deals with the geochemical characteristics of the Holocene sediments from Alamdanga area, Chuadanga district, Bangladesh. Main goals of the study are to delineate source rock characteristics, degree of chemical weathering and sorting processes and behavior of redox conditions during deposition of the sediments. Geochemical characteristics of the sediments show comparatively a wide variation in accordance with stratigraphy in their major element contents (e.g. SiO 69.46-82.13, AlO 2.28-8.88 in wt%), reflecting the distinctive provenance and in part an unstable period in terms of tectonic activity. Geochemical classification of the sediments shows mostly sub-arkose with few sub-litharenites. Some major and trace elements display comprehensible correlation with AlO confirming their possible hydraulic fractionation. The chemical index of alteration (CIA*), W* index, index of compositional variability (ICV), plagioclase index of alteration (PIA*) values and the ratio of SiO/AlO, suggest low degrees of chemical weathering in the source areas as well as immature to moderately mature the sediments. The sediments suggest semi-arid climatic trends within oxic deltaic depositional conditions during the Holocene, at 3-12 ka. Whole rock geochemistry and discrimination diagrams demonstrate the continental signature derivatives, which might have been derived from the felsic to intermediate igneous rocks (granitic plutonic rocks) as well as from quartzose sedimentary/metamorphic provenance. These typical sources are present in a vast region of the Himalayan belt and catchment areas of Ganges. The tectonic setting of the sediments demarcates typically passive margin with slightly continental arc system. [ABSTRACT FROM AUTHOR]

The Dupi Tila Formation is composed of yellow to light brown medium to very fine moderately hard to loose sandstone, siltstone, silty clay, mudstone and shale with some conglomerates with clasts of petrified wood. The lithofacies of matrix supported conglomerate, trough cross bedded conglomerate, massive sandstone, trough cross bedded sandstone, planar cross bedded sandstone, ripple cross laminated sandstone-siltstone, flaser laminated sandstone-shale, lenticular laminated sandstone-siltstone-shale, parallel laminated sandstone-siltstone, wavy laminated shale, parallel laminated blue shale, and mudstone are delineated within this formation. Based on the grain size, sedimentary structures, water depth and genesis of individual facies, facies are grouped into three types of facies associations like (i) coarse-grained conglomerate facies association in relation to tractive current deposits of alluvial fan set up at the base of litho-succession (FAC), (ii) medium to fine-grained sandstone-siltstone-mudstone facies association or facies association in relation to strong tide (FAT) characterizing the middle part of litho-succession, (iii) very fine-grained sandstone-siltstone-mudstone facies association in relation to less frequent weak tide or heterolithic facies association (FAHL) characterizing upper part of litho-succession and shallow marine facies association (FASM) composing the uppermost litho-succession. Presence of gluconite indicates that the depositional environment was shallow to deep marine. The dominant paleoflow direction during the deposition of Dupi Tila Formation was toward southeast to southwestern direction. The rivers were of braided type at the piedmont alluvial depositional set up at the lower part, which later changed to estuarine-tidal flat type environmental set up in the middle part to upper part and paleo-environment was shallow marine in the uppermost part. [ABSTRACT FROM AUTHOR]

Lassa virus (LASV) is responsible for an acute viral hemorrhagic fever known as Lassa fever. Sequence analyses of LASV proteome identified the most immunogenic protein that led to predict both T-cell and B-cell epitopes and further target and binding site depiction could allow novel drug findings for drug discovery field against this virus. To induce both humoral and cell-mediated immunity peptide sequence SSNLYKGVY, conserved region 41–49 amino acids were found as the most potential B-cell and T-cell epitopes, respectively. The peptide sequence might intermingle with 17 HLA-I and 16 HLA-II molecules, also cover 49.15–96.82% population coverage within the common people of different countries where Lassa virus is endemic. To ensure the binding affinity to both HLA-I and HLA-II molecules were employed in docking simulation with suggested epitope sequence. Further the predicted 3D structure of the most immunogenic protein was analyzed to reveal out the binding site for the drug design against Lassa Virus. Herein, sequence analyses of proteome identified the most immunogenic protein that led to predict both T-cell and B-cell epitopes and further target and binding site depiction could allow novel drug findings for drug discovery field against this virus. [ABSTRACT FROM AUTHOR]

To examine the rain-fed Aman rice yield fluctuation due to climatic anomalies overtimes in Bangladesh, we used climate-induced yield index (CIYI), ensemble empirical mode decomposition (EEMD), step-wise multiple regression, isotopic signature, wavelet transform coherence (WTC) and random forest (RF) model. In this work, daily multiple source climatic data which were collected between 1980 and 2017, from 18 weather stations and five atmospheric circulation indices were used for this purpose. The key findings were as follows; by employing principal component analysis (PCA), six temporal variability modes were identified as six corresponding sub-regions with various Aman rice CIYI fluctuations. The Aman rice CIYI in different sub-regions represented a noteworthy 3–4-year quasi-oscillation using the EEMD. The key climate variables (KCVs) including the potential evapotranspiration and cloud cover in September, the minimum temperature in August, and precipitation in July, August, and October were the best rice yield prediction signals in these sub-regions. The results suggest that Aman rice yield could likely decline by 33.59%, and 3.37% in the southwestern and southeastern regions, respectively, if KCV increased by 1 °C or 1%. The RF model suggests that the Indian Ocean Dipole (IOD) significantly influenced the rice yield. Isotopic signatures were employed to confirm the fluctuation and anti-amount effect during the Aman rice-growing period in Bangladesh. The results obtained in this study could be used as a guideline for sustainable mitigation and adaptation measures in managing agro-meteorological hazards in Bangladesh. [ABSTRACT FROM AUTHOR]