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1.
Mymensingh Med J ; 33(3): 656-663, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38944703

ABSTRACT

Chronic obstructive pulmonary disease (COPD) is a preventable and treatable disease of airflow limitation that is not fully reversible. COPD affects the lungs and produces significant systemic consequences. In Bangladesh, the prevalence of COPD after 40 years of age is 21.24% and the general population is 4.3%. COPD leads to a sedentary life, which reduces the functional status of the individual. Functional status assessment is vital for appropriate therapy and rehabilitation programs in COPD patients. A Sit-to-stand test (STST) has been proposed as a better alternative to 6MWT, but a Squat-to-stand test (SqTST) to test their ability to stand from the squatting position will be more appropriate in rural patients. This study was conducted using a cross-sectional observational design from July 2020 and September 2021 in the Department of Respiratory Medicine at the National Institute of Diseases of the Chest and Hospital, Bangladesh. Sixty (60) diagnosed cases of COPD patients were enrolled in this study. Severities of airflow obstruction according to GOLD were categorized on the basis of post-bronchodilator FEV1 by spirometry. SqTST was performed on all patients, and functional status was recorded. All data were collected using a preformed questionnaire. Statistical analyses of the findings were carried out using SPSS version 23.0. In this study, the majority of 21(35.0%) patients had very severe COPD, and almost half (48.3%) of the patients had abnormal SqTST. A significant relation was found between the severity of COPD with SqTST (p=0.001). Based on the receiver-operator characteristic (ROC) curve, SqTST had an area under curve 0.901. SqTST had 82.1% sensitivity, 85.7% specificity, 83.3% accuracy, 91.4% positive predictive value, and 72.0% negative predictive value to find severe COPD cases in stable COPD patients. ROC was constructed using SqTST, which gave a cut-off value <7.0, with 82.1% sensitivity and 85.7% specificity for predicting severe COPD. From this study, it may be concluded that SqTST is a clinically useful tool to assess the functional status of stable COPD patients.


Subject(s)
Pulmonary Disease, Chronic Obstructive , Humans , Pulmonary Disease, Chronic Obstructive/physiopathology , Pulmonary Disease, Chronic Obstructive/diagnosis , Male , Cross-Sectional Studies , Female , Middle Aged , Bangladesh/epidemiology , Aged , Exercise Test/methods , Respiratory Function Tests/methods , ROC Curve
2.
Mymensingh Med J ; 33(3): 805-809, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38944725

ABSTRACT

Stroke is one of the most common neurological disorder and third most common cause of death in the world. Low vitamin D concentrations have been shown to predict risk of cardiovascular disease and all-cause of mortality. The aim of this study was to estimate serum vitamin D level in acute ischemic stroke patients. This comparative cross-sectional type of study was conducted in the Department of Neurology and Department of Medicine at Mymensingh Medical College and Hospital, Bangladesh from November 2017 to June 2019 with a total number of 100 study subjects. Total fifty patients with acute ischemic stroke were enrolled in Group A and another fifty age and sex matched volunteer subjects were enrolled in Group B with no prior history of stroke or transient ischemic attacks. Serum vitamin D levels, fasting plasma glucose and lipid profile were assessed in both groups and compared with each other. P value <0.05 was considered as significant in the study. Mean fasting blood sugar, serum fasting total cholesterol (TC), serum fasting triglycerides, serum fasting Low density lipoprotein (LDL) were significantly higher in Group A than Group B (p<0.05). Serum vitamin D level in Group A was 25.28±8.47ng/ml and in Group B was 30.90±5.80, (p=0.001). Insufficient vitamin D level was found in 52.0% of ischemic stroke patients and in 30% of healthy controls (p=0.0002). Vitamin D deficiency was found in 20.0% ischemic stroke patients and 10.0% in healthy controls. This study demonstrates a positive association between low serum vitamin D level and acute ischemic stroke. Further studies are required to determine whether vitamin D supplementation could improve functional outcome in patients with ischemic stroke.


Subject(s)
Ischemic Stroke , Vitamin D Deficiency , Vitamin D , Humans , Male , Female , Vitamin D/blood , Ischemic Stroke/blood , Ischemic Stroke/epidemiology , Cross-Sectional Studies , Middle Aged , Vitamin D Deficiency/blood , Vitamin D Deficiency/complications , Vitamin D Deficiency/epidemiology , Bangladesh/epidemiology , Aged , Adult , Case-Control Studies , Blood Glucose/analysis
3.
Chem Asian J ; : e202300926, 2024 May 09.
Article in English | MEDLINE | ID: mdl-38721713

ABSTRACT

The transition of the global energy market towards an environment-friendly, sustainable society requires a profound transformation from fossil fuel to zero carbon emission fuel. To cope with this goal production of renewable energy is accelerating worldwide. Hydrogen is a clean energy carrier, due to its clean combustion and abundance. Nonetheless, its storage is a critical challenge to its success. Hydrogen must be stored long after being produced and transported to a storage site. Physical hydrogen storage (PHS) is vital among hydrogen storage modes, and its shortcoming needs to overcome for its successful and economic benefits. This review intends to discuss the techniques and applications of physical hydrogen storage in the state of compressed gas, liquefied hydrogen gas, and cold/cryo compressed gas concerning their working principle, chemical and physical properties, influencing factors for physical hydrogen storage, and transportation, economics, and global outlook. In addition, insights of several probable PHS systems are highlighted. The outcomes of this review envisioned that the PHS still necessitates technological advancements despite having remarkable success. The limitation opens the door to further research, which would be helpful for efficient and long-term physical hydrogen storage.

4.
Molecules ; 29(7)2024 Mar 31.
Article in English | MEDLINE | ID: mdl-38611848

ABSTRACT

Sugar industries generate substantial quantities of waste biomass after the extraction of sugar water from sugarcane stems, while biomass-derived porous carbon has currently received huge research attention for its sustainable application in energy storage systems. Hence, we have investigated waste sugarcane bagasse (WSB) as a cheap and potential source of porous carbon for supercapacitors. The electrochemical capacitive performance of WSB-derived carbon was further enhanced through hybridization with silicon dioxide (SiO2) as a cost-effective pseudocapacitance material. Porous WSB-C/SiO2 nanocomposites were prepared via the in situ pyrolysis of tetraethyl orthosilicate (TEOS)-modified WSB biomass. The morphological analysis confirms the pyrolytic growth of SiO2 nanospheres on WSB-C. The electrochemical performance of WSB-C/SiO2 nanocomposites was optimized by varying the SiO2 content, using two different electrolytes. The capacitance of activated WSB-C was remarkably enhanced upon hybridization with SiO2, while the nanocomposite electrode demonstrated superior specific capacitance in 6 M KOH electrolyte compared to neutral Na2SO4 electrolyte. A maximum specific capacitance of 362.3 F/g at 0.25 A/g was achieved for the WSB-C/SiO2 105 nanocomposite. The capacitance retention was slightly lower in nanocomposite electrodes (91.7-86.9%) than in pure WSB-C (97.4%) but still satisfactory. A symmetric WSB-C/SiO2 105//WSB-C/SiO2 105 supercapacitor was fabricated and achieved an energy density of 50.3 Wh kg-1 at a power density of 250 W kg-1, which is substantially higher than the WSB-C//WSB-C supercapacitor (22.1 Wh kg-1).

5.
J Family Med Prim Care ; 13(1): 278-284, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38482273

ABSTRACT

Introduction: Schizophrenia is a severe mental disorder affecting millions worldwide. Family caregivers play a vital role in patient treatment and recovery, but their responsibilities can be physically and emotionally exhausting. There is limited research on caregiver burden in Bangladesh, prompting this study to identify factors associated with the burden among caregivers of schizophrenic patients. Methods: This cross-sectional study collected data from 175 caregivers from January to December 2020 in Dhaka, Bangladesh. A semi-structured questionnaire and a validated Bangla version of the Zarit Burden Interview (ZBI) scale were used to assess the burden of primary caregivers and associated factors in caring for patients with schizophrenia. Results: Participants' mean age was 34.02 ± 10.45 years, with 26.9% in the 34-41 age group. 49.1% were housewives, with most earning 5000 to 15000 taka monthly. Spouses accounted for 28.6% of caregivers. Most patients had an illness duration of less than five years (66.3%). Mean ZBI score was 49.49 ± 12.06, indicating moderate to severe burden. Factors significantly associated with caregiver burden included age, gender, occupation, income, marital status, house condition, relationship with patients, illness stage, and duration. Conclusion: This study highlights the burden experienced by caregivers of schizophrenic patients in Bangladesh and identifies factors associated with the burden. It recommends community interventions and psychosocial provisions to address this issue and inform targeted interventions to reduce caregiver burden. These findings provide insights for a comprehensive plan to manage such cases in the future.

7.
Med Biol Eng Comput ; 62(5): 1549-1567, 2024 May.
Article in English | MEDLINE | ID: mdl-38308669

ABSTRACT

Radiofrequency ablation is a nominally invasive technique to eradicate cancerous or non-cancerous cells by heating. However, it is still hampered to acquire a successful cell destruction process due to inappropriate RF intensities that will not entirely obliterate tumorous tissues, causing in treatment failure. In this study, we are acquainted with a nanoassisted RF ablation procedure of cardiac tumor to provide better outcomes for long-term survival rate without any recurrences. A three-dimensional thermo-electric energy model is employed to investigate nanothermal field and ablation efficiency into the left atrium tumor. The cell death model is adopted to quantify the degree of tissue injury while injecting the Fe3O4 nanoparticles concentrations up to 20% into the target tissue. The results reveal that when nanothermal field extents as a function of tissue depth (10 mm) from the electrode tip, the increasing thermal rates were approximately 0.54362%, 3.17039%, and 7.27397% for the particle concentration levels of 7%, 10%, and 15% compared with no-particle case. In the 7% Fe3O4 nanoparticles, 100% fractional damage index is achieved after ablation time of 18 s whereas tissue annihilation approach proceeds longer to complete for no-particle case. The outcomes indicate that injecting nanoparticles may lessen ablation time in surgeries and prevent damage to adjacent healthy tissue.


Subject(s)
Catheter Ablation , Heart Neoplasms , Radiofrequency Ablation , Humans , Computer Simulation , Catheter Ablation/methods , Heart Atria/surgery
8.
Mymensingh Med J ; 33(1): 9-15, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38163767

ABSTRACT

Magnesium (Mg) has important effects on vascular system and deficiency of this cation is thought to be a risk factor for cerebrovascular atherosclerosis and complications. The study was planned to find out the association of serum magnesium level with severity of neurological disability in patient with acute ischemic stroke. This cross-sectional descriptive study was conducted in the department of Neurology and Medicine at Mymensingh Medical College & Hospital, Mymensingh from June, 2018 to October, 2019. Patients with acute ischemic stroke were evaluated following informed written consent. Diagnosis was confirmed by neuroimaging of brain. Moreover, serum magnesium assay was done for each patient. Data were collected by interview, clinical examination and laboratory investigations of patients using a case record form and analysis was carried out by using the SPSS 22.0 (IBM Inc., Armonk, NY, USA). Mean age of acute ischemic stroke patients was 63.94±13.93 years with male predominance (58.30%). Majority of the respondents (70.2%) had NIH Stroke Scale (NIHSS) score 5-15 (moderate stroke), 13.1% had score 1-5 (minor stroke), 13.1% had score15-20 (Moderate to severe stroke) and 3.6% had score 21-42 (severe stroke). Mean serum magnesium level was 1.83±0.283mg/dl. Hypomagnesaemia was present in 28(33.3%) patients and it was related with higher NIHSS scoring (p<0.05). Multiple regression showed that among the risk factors, serum magnesium level was independently associated with severity of neurological disability of the acute ischemic stroke (p<0.001). In this study, the correlation coefficient between serum magnesium level and NIHSS score was found as r= - 0.667 which showed negative relationship between serum magnesium and NIHSS score. Lower serum magnesium level is associated with the severity of neurological disability of acute ischemic stroke patient. Further case-control studies are required to validate this finding.


Subject(s)
Brain Ischemia , Ischemic Stroke , Stroke , Humans , Male , Middle Aged , Aged , Female , Brain Ischemia/complications , Magnesium , Cross-Sectional Studies
9.
Lifetime Data Anal ; 30(1): 181-212, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37659991

ABSTRACT

To achieve the goal of providing the best possible care to each individual under their care, physicians need to customize treatments for individuals with the same health state, especially when treating diseases that can progress further and require additional treatments, such as cancer. Making decisions at multiple stages as a disease progresses can be formalized as a dynamic treatment regime (DTR). Most of the existing optimization approaches for estimating dynamic treatment regimes including the popular method of Q-learning were developed in a frequentist context. Recently, a general Bayesian machine learning framework that facilitates using Bayesian regression modeling to optimize DTRs has been proposed. In this article, we adapt this approach to censored outcomes using Bayesian additive regression trees (BART) for each stage under the accelerated failure time modeling framework, along with simulation studies and a real data example that compare the proposed approach with Q-learning. We also develop an R wrapper function that utilizes a standard BART survival model to optimize DTRs for censored outcomes. The wrapper function can easily be extended to accommodate any type of Bayesian machine learning model.


Subject(s)
Decision Making , Humans , Bayes Theorem , Computer Simulation , Precision Medicine , Survival Analysis , Transplantation, Homologous , Hematopoietic Stem Cells
10.
Mymensingh Med J ; 32(4): 939-946, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37777884

ABSTRACT

Thyroid lesions are very common problem in Bangladesh. To categorize the type of lesion, FNAC is a reliable, minimally invasive and cost-effective diagnostic modality. In routine cytology, precise categorization into benign and malignant is highly subjective. So, additional methods are needed to improve the accuracy of cytological diagnosis. Computerized semi-automatic nuclear morphometry is an objective and reproducible tool for quantitative evaluation of nuclear features which may help to differentiate between benign and malignant thyroid lesions in cytology. Objective of the study was to apply morphometry with regard to nuclear size parameters, shape parameters and nuclear chromasia with derivation of suitable cutoff values to differentiate benign and malignant lesions of thyroid gland. This cross-sectional study was done in total 55 cases at the Department of Pathology, Bangabandhu Sheikh Mujib Medical University, Bangladesh from March 2018 to February 2020. Morphometry was done on images containing diagnostic cells captured from cytological smears with open source ImageJ morphometric software. In this study, all the nuclear size parameters and one nuclear shape parameter was found significant in differentiating benign and malignant lesions. No significant difference was observed in analysis of chromasia parameter. The cut-off values derived between all benign and malignant lesions for mean value of nuclear area, maximum feret diameter, perimeter and aspect ratio were 40.20µm², 8.46µm, 6.68µm, 28.28µm and 1.35 respectively with sensitivity of 86%, 95%, 81%, 90% and specificity of 97%, 93%, 97% and 97% respectively. The Nuclear morphometry may be used as an adjunctive tool to routine thyroid cytology.


Subject(s)
Cytodiagnosis , Thyroid Gland , Humans , Thyroid Gland/pathology , Cross-Sectional Studies , Cytodiagnosis/methods , Bangladesh
11.
ACS Omega ; 8(39): 35845-35855, 2023 Oct 03.
Article in English | MEDLINE | ID: mdl-37810722

ABSTRACT

The experiment was conducted at the research field, Department of Agronomy, Hajee Mohammad Danesh Science and Technology University, Dinajpur from December 2017 to May 2018 to find out the best treatment of foliar application of urea on the growth and yield of boro rice cv. BRRI dhan28. The experiment consisted of 10 treatments, laid out in a randomized complete block design in triplicate. The recommended doses (RD) of urea, TSP, MOP, gypsum, ZnSO4, and borax were applied during land preparation except for urea at 250, 75, 100, 75, 7, and 5 kg ha-1, respectively, where urea was applied as per treatment specification. The results revealed that the application of N fertilizer as foliage along with soil significantly influenced the growth, plant characteristics, and yield of BRRI dhan28. There was no significant difference between T8 (70% in soil and 10% as foliage) and T9 (100% in soil) treatment regarding the maximum panicle length (21.43 and 20.71 cm), fertile grains (117.40 and 113.30), total grains (134.40 and 130.97), 1000-grain weight (24.56 and 23.56 g), grain yield (5.91 and 5.74 t ha-1), straw yield (7.83 and 7.92 t ha-1), biological yield (13.74 and 13.66 t ha-1), and harvest index (43.01 and 42.02%), respectively, in this study. These results indicated that N fertilization as direct soil application (70%) and as foliage application (10%), i.e., 80% N fertilization, produced the highest grain yield and major yield traits which we received by 100% N fertilization as soil that was practiced traditionally by the farmers. The effect of overfertilization (T10) was not positive, producing the highest number of noneffective tillers and sterile grains (nonfilled grains). Therefore, it is possible to achieve an equivalent or more yield by saving 20% urea by the combination of soil (70%) and foliage (10%) application as compared to the traditional method of fertilizer application (100% in soil).

12.
Ann Med Surg (Lond) ; 85(8): 3816-3826, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37554920

ABSTRACT

This study aimed to examine the differences in epidemiologic and disease aspects among patients with coronavirus disease-19 (COVID-19). Methods: The authors reviewed the hospital records between April 2020 and September 2021 and followed up on the patients for post-COVID complications. Findings: Older adult patients were predominantly affected during the third wave, and middle-aged patients were predominantly affected during the first and second waves. Men were predominantly admitted, considering the three waves, although more women were admitted in the second wave. Cough was more common in the second and third waves than in the first wave 522 (59.7%). Respiratory distress was the most common in the third wave, 251(67.1%), and least common in the first wave, 403 (46.1%). Anosmia was more common in the third wave 116 (31.2%). In the third wave, patients presenting in a critical state 23 (6.2%) and with severe disease 152 (40.8%) were more common. The hospital admission median (IQR) was longer in the first wave, 12 (8-20), than in other waves. More patients were admitted in the first wave (52%) than in the other waves, and patients received more oxygen in the third wave (75%) than in the other waves. Death occurred more commonly in the first wave (51%) than in the other waves. The positivity rate was higher in the third wave (22.8%) than in the other waves. In the third wave, the positivity rate was higher in women (24.3%) than in men. Post-COVID cough increased in the second wave, and fatigue was higher in the third wave than in the other waves. Tiredness and memory loss were greater during the second wave than in other waves. Conclusion: The authors found differences in the presentation, outcomes, and hospital epidemiologic trend of COVID-19 among the three waves.

13.
RSC Adv ; 13(34): 23558-23569, 2023 Aug 04.
Article in English | MEDLINE | ID: mdl-37555094

ABSTRACT

A comprehensive investigation of the gas sensing potential of BeS monolayer has been conducted using DFT calculations. Twelve common pollutant gases: NH3, NO2, NO, CO, CO2, CH4, H2, O2, N2, H2S, H2O and SO2, have been studied. Our analysis reveals defect states in the band structure near the Fermi level and strong hybridization between gas molecule orbitals and the BeS monolayer. We observe higher adsorption energies for NH3 and CO compared to other popular gas sensing materials. The optical properties of CO2 and NO2 adsorbed on the BeS monolayer show increased reflectivity and absorption coefficient in the UV and far infrared region. Tensile strain has minimal impact on adsorption energy, while biaxial compressive strains enhance the gas sensing capability of the BeS monolayer. The application of an electric field offers control over gas adsorption and desorption. We propose the BeS monolayer as a promising candidate for future gas molecule sensing applications due to its high adsorption energy, rapid recovery time, and distinct optical properties.

14.
Mymensingh Med J ; 32(3): 812-817, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37391979

ABSTRACT

To evaluate the extra biliary complications of laparoscopic cholecystectomy and the outcome of management of those complications. This descriptive observational study was carried out at CMH Dhaka and CMH Jashore, Bangladesh from March 2016 to March 2022. A total of 1420 patients who underwent Laparoscopic cholecystectomy were included in this study. Extra biliary complications of laparoscopic cholecystectomy were divided into i) Access related ii) Intraoperative (procedure related) and iii) Postoperative complications. The incidence of access-related, intra-operative or procedure-related and postoperative complications was 2.88%, 4.91% and 1.82% respectively. Access related complications were extra-peritoneal insufflations 1.34%, port site bleeding 1.26%, small bowel laceration 0.21% and transverse colon injury 0.07%. Intraoperative or procedural extra biliary complications were liver injury 0.56%, duodenal perforation 0.07%, colon injury 0.07%, bleeding through cystic artery 0.49% and bleeding from gall bladder bed 1.12%. Postoperative complications were port site infection (PSI) 1.05%, port site hernia (PSH) 0.56%, major sepsis 0.14% and ischemic stroke 0.07%. Two of colonic injuries were the major complications encountered in this series, diagnosed during the procedure and converted to open procedure. Duodenal perforation encountered in one case during difficult dissection in the Callot's triangle, diagnosed during the procedure and managed laparoscopically by intra-corporeal suturing. No mortality reported in this series. Extra biliary complications are almost equally common as biliary complications in laparoscopic cholecystectomy and can be life-threatening. An early diagnosis and effective management of complications accordingly, are the utmost requirement for favorable outcome in laparoscopic cholecystectomy.


Subject(s)
Abdominal Injuries , Cholecystectomy, Laparoscopic , Humans , Cholecystectomy, Laparoscopic/adverse effects , Bangladesh , Colon , Dissection
15.
Anal Bioanal Chem ; 415(17): 3487-3501, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37219581

ABSTRACT

Early detection of histamine in foodstuffs/beverages could be useful in preventing various diseases. In this work, we have prepared a free-standing hybrid mat based on manganese cobalt (2-methylimodazole)-metal organic frameworks (Mn-Co(2-MeIm)MOF) and carbon nanofibers (CNFs) and explored as a non-enzymatic electrochemical sensor for determining the freshness of fish and bananas based on histamine estimation. As-developed hybrid mat possesses high porosity with a large specific surface area and excellent hydrophilicity those allow easy access of analyte molecules to the redox-active metal sites of MOF. Furthermore, the multiple functional groups of the MOF matrix can act as active adsorption sites for catalysis. The Mn-Co(2-MeIm)MOF@CNF mat-modified GC electrode demonstrated excellent electrocatalytic activities toward the oxidation of histamine under acidic conditions (pH = 5.0) with a faster electron transfer kinetics and superior fouling resistance. The Co(2-MeIm)MOF@CNF/GCE sensor exhibited a wide linear range from 10 to 1500 µM with a low limit of detection (LOD) of 89.6 nM and a high sensitivity of 107.3 µA mM-1 cm-2. Importantly, as-developed Nb(BTC)MOF@CNF/GCE sensor is enabled to detect histamine in fish and banana samples stored for different periods of time, which thus indicates its practical viability as analytical histamine detector.


Subject(s)
Carbon , Nanofibers , Animals , Carbon/chemistry , Cobalt/chemistry , Manganese , Histamine , Nanofibers/chemistry , Electrodes , Electrochemical Techniques
16.
Polymers (Basel) ; 15(6)2023 Mar 20.
Article in English | MEDLINE | ID: mdl-36987308

ABSTRACT

Polypyrrole (PPy) nanoparticles are reliable conducting polymers with many industrial applications. Nevertheless, owing to disadvantages in structure and morphology, producing PPy with high electrical conductivity is challenging. In this study, a chemical oxidative polymerization-assisted ultra-sonication method was used to synthesize PPy with high conductivity. The influence of critical sonication parameters such as time and power on the structure, morphology, and electrical properties was examined using response surface methodology. Various analyses such as SEM, FTIR, DSC, and TGA were performed on the PPy. An R2 value of 0.8699 from the regression analysis suggested a fine correlation between the observed and predicted values of PPy conductivity. Using response surface plots and contour line diagrams, the optimum sonication time and sonication power were found to be 17 min and 24 W, respectively, generating a maximum conductivity of 2.334 S/cm. Meanwhile, the model predicted 2.249 S/cm conductivity, indicating successful alignment with the experimental data and incurring marginal error. SEM results demonstrated that the morphology of the particles was almost spherical, whereas the FTIR spectra indicated the presence of certain functional groups in the PPy. The obtained PPy with high conductivity can be a promising conducting material with various applications, such as in supercapacitors, sensors, and other smart electronic devices.

17.
Nanomaterials (Basel) ; 13(4)2023 Feb 06.
Article in English | MEDLINE | ID: mdl-36839010

ABSTRACT

In this study, poly(m-aminophenol) (PmAP) has been investigated as a multi-functional conductive supercapacitor binder to replace the conventional non-conductive binder, namely, poly(vinylene difluoride) (PVDF). The kye benefits of using PmAP are that it is easily soluble in common organic solvent and has good film-forming properties, and also its chemical functionalities can be involved in pseudocapacitive reactions to boost the capacitance performance of the electrode. A new ternary nanocomposite film based on vanadium pentoxide (V2O5), amino-functionalized graphene (amino-FG) and PmAP was fabricated via hydrothermal growth of V2O5 nanoparticles on graphene surfaces and then blending with PmAP/DMSO and solution casting. The electrochemical performances of V2O5/amino-FG/PmAP nanocomposite were evaluated in two different electrolytes, such as KCl and Li2SO4, and compared with those of V2O5/amino-FG nanocomposite with PVDF binder. The cyclic voltametric (CV) results of the V2O5/amino-FG/PmAP nanocomposite exhibited strong pseudocapacitive responses from the V2O5 and PmAP phases, while the faradaic redox reactions on the V2O5/amino-FG/PVDF electrode were suppressed by the inferior conductivity of the PVDF. The V2O5/amino-FG/PmAP electrode delivered a 5-fold greater specific capacitance than the V2O5/amino-FG/PVDF electrode. Solid-state asymmetric supercapacitors (ASCs) were assembled with V2O5/amino-FG/PmAP film as a positive electrode, and their electrochemical properties were examined in both KCl and Li2SO4 electrolytes. Although the KCl electrolyte-based ASC has greater specific capacitance, the Li2SO4 electrolyte-based ASC delivers a higher energy density of 51.6 Wh/kg and superior cycling stability.

18.
Neural Comput Appl ; 35(7): 5165-5191, 2023.
Article in English | MEDLINE | ID: mdl-36311167

ABSTRACT

Capturing time and frequency relationships of time series signals offers an inherent barrier for automatic human activity recognition (HAR) from wearable sensor data. Extracting spatiotemporal context from the feature space of the sensor reading sequence is challenging for the current recurrent, convolutional, or hybrid activity recognition models. The overall classification accuracy also gets affected by large size feature maps that these models generate. To this end, in this work, we have put forth a hybrid architecture for wearable sensor data-based HAR. We initially use Continuous Wavelet Transform to encode the time series of sensor data as multi-channel images. Then, we utilize a Spatial Attention-aided Convolutional Neural Network (CNN) to extract higher-dimensional features. To find the most essential features for recognizing human activities, we develop a novel feature selection (FS) method. In order to identify the fitness of the features for the FS, we first employ three filter-based methods: Mutual Information (MI), Relief-F, and minimum redundancy maximum relevance (mRMR). The best set of features is then chosen by removing the lower-ranked features using a modified version of the Genetic Algorithm (GA). The K-Nearest Neighbors (KNN) classifier is then used to categorize human activities. We conduct comprehensive experiments on five well-known, publicly accessible HAR datasets, namely UCI-HAR, WISDM, MHEALTH, PAMAP2, and HHAR. Our model significantly outperforms the state-of-the-art models in terms of classification performance. We also observe an improvement in overall recognition accuracy with the use of GA-based FS technique with a lower number of features. The source code of the paper is publicly available here https://github.com/apusarkar2195/HAR_WaveletTransform_SpatialAttention_FeatureSelection.

19.
Life (Basel) ; 12(12)2022 Dec 07.
Article in English | MEDLINE | ID: mdl-36556416

ABSTRACT

Nitrogen (N) is a highly essential macronutrient for plant root growth and grain yield (GY). To assess the relationship among N, root traits, and the yield of boro (dry season irrigated) rice, a pot experiment was performed in the Department of Agronomy, Bangladesh Agricultural University, Mymensingh, Bangladesh, during the boro rice season of 2020-2021. Three boro rice varieties, namely BRRI dhan29, Hira-2, and Binadhan-10, were planted at four N doses: 0 kg ha-1 (N0), 70 kg ha-1 (N70), 140 kg ha-1 (N140), and 210 kg ha-1 (N210). The experiment was conducted following a completely randomized design with three replicates. The varieties were evaluated for root number (RN), root length (RL), root volume (RV), root porosity (RP), leaf area index (LAI), total dry matter (TDM), and yield. The results indicated that the Binadhan-10, Hira-2, and BRRI dhan29 varieties produced better root characteristics under at the N140 and N210 levels. A substantial positive association was noticed between the grain yield and the root traits, except for root porosity. Based on the root traits and growth dynamics, Binadhan-10 performed the best at the N140 level and produced the highest grain yield (26.96 g pot-1), followed by Hira-2 (26.35 g pot-1) and BRRI dhan29 (25.90 g pot-1).

20.
J Adv Vet Anim Res ; 9(3): 374-382, 2022 Sep.
Article in English | MEDLINE | ID: mdl-36382039

ABSTRACT

Objective: The study aimed to develop and assess an Android app designed for farmers with a low educational status that can formulate a least-cost ration. Materials and Methods: First, a computer-android-based app named BLRI FeedMaster was developed to guide users in formulating a balanced ration at the least cost. A survey was conducted on 30 livestock officers and 18 farmers with 50 cattle to evaluate its efficacy at the field level. The study outcomes were milk yield, feeding cost, milk composition, time, and cost for management before and after using the BLRI FeedMaster app. Descriptive statistics and paired sample t-tests were used to analyze the data. Results: After adopting the BLRI FeedMaster app, a significant increase was observed in daily average milk yield (9.39 ± 0.32 l from 8.37 ± 0.36 l), while a considerable decrease was observed in daily average feed quantity (4.88 ± 0.15 kg from 5.60 ± 0.17 kg) and feed cost (BDT 28.00 ± 0.50 from BDT 29.75 ± 0.49). Besides, the number of visits, time, and cost for seeking professional services regarding feed, health care, and other information was significantly minimized. The number of visits decreased to 0.36 ± 013 from 3.07 ± 0.38, and the consumed time was reduced from 270 ± 34.30 to 235.71 ± 59.42 min (p < 0.05) after adopting the app. Conclusion: Hence, this app was very beneficial for farmers with a low economic and educational background and may ultimately help farmers with profitable animal farming and sustainable production in the least developed countries like Bangladesh.

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