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Heavy Minerals in Sands along Brahmaputra (Jamuna) River of Bangladesh

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International Journal of Geosciences 2016年第1期7卷 47-52页

作者： md. Ibrahim Khalil md. Nazrul Islam Khan md. Zafrul Kabir Ratan Kumar Majumd.r md. Idris ali Debasish Paul Syed Mohammad Azharul Islam Nuclear Minerals Unit Atomic Energy Research Establishment Dhaka Bangladesh Material Science Division Atomic Energy Center Bangladesh Atomic Energy Commission Dhaka Bangladesh Health Physics and Radioactive Waste Management Unit Atomic Energy Research Establishment Dhaka Bangladesh Department of Physics Jahangirnagar University Dhaka Bangladesh

Sands along Brahmaputra River of Bangladesh have long been considered to be a source of heavy minerals (HMs) since it traversed a long way through various terrains. An attempt has been made under this research work to determine the kinds and amounts of heavy minerals in the sands sourced from the river system. Samples from 14 locations along Brahmaputra River covering 30 km distance from upstream to downstream of the river are found to contain different heavy minerals concentration with a range of 7.92 - 25.16 weight% with the remaining of the sample comprising silicate and aluminosilicates. Mineral characterization from peak positions in diffractogram of X-ray Diffraction (XRD) evaluate quartz, feldspar and mica are major categories light mineral while rutile, magnetite, illmenite, zircon, monazite, garnet, uranium arsenide and uranium fluoride are the major types heavy minerals. Ilmenite and rutile are main contributors of total heavy mineral (THM). Titanium bearing minerals ilmenite and rutile contributes 26.22% - 31.01% and 14.57% - 23.50% of THM. In the present study area, most of the sands are found to be fine and medium grained as obtained from the particle sizes analysis using 18- to 230-mesh.

关键词： Heavy Minerals River Sand Bangladesh

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Antidepressant-Like Activity of Methanolic Extract of the Seeds of <i>Trachysperum ammi</i>in Swiss Albino Mice

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Pharmacology & Pharmacy 2018年第12期9卷 503-514页

作者： md. Rashidur Rahman Mohammad ali Mostakim Sharif Sadiur Rahman Sajon md. Abdul Mannan md. Shahed-Al-Mahmud Department of Pharmacy Jessore University of Science and Technology Jessore Bangladesh Department of Pharmacy Stamford University Bangladesh Dhaka Bangladesh Department of Microbiology and Immunology School of Medicine Tzu Chi University Hualian Taiwan

Trachysperum ammi has been traditionally used for the treatment of neurological disorders such as depression and anxiety. To date, T. ammi has reported for its chemical constituents in different diseases condition. The traditional evidence convinced us to perform the antidepressant-like activity of methanolic extract of Trachysperum ammi (META). The antidepressant activity of META assessed by using forced swimming test (FST), tail suspension test (TST), and locomotor activity test. The seed parts of META at doses level of 50, 100 and 200 mg/kg body weight administered orally to examine the CNS stimulants activity test in mice behavioral models. Here, we reported that META significantly reduced immobility time in the FST after repeated administration of 50, 100 and 200 mg/kg to mice for 14 days. The intensity of immobility significantly reduced at all of the doses (p < 0.05) whereas, we were found the strongest effect observed at 200 mg/kg. The antidepressant-like effect of META caused the reduction (p < 0.05) in the immobility in TST of mice when orally administered with 50, 100 and 200 mg/kg for 14 days, respectively. Additionally, we were executed locomotor activity test to check the motor stimulating activity. META has employed at a dosage of 50, 100 and 200 mg/kg for 14 days, the results have found that 50 mg/kg produced the locomotion effects as similar to the control group. Interestingly, the locomotion, rearing, and defecation significantly (p < 0.05) increased at the dosage of 100 and 200 mg/kg of META. Our present findings suggest that the seed parts of Trachysperum ammi may possess antidepressant-like activity which may use as a supportive treatment to management of neurological disorders.

关键词： Trachysperum ammi Antidepressant CNS Stimulants Forced Swimming

Ultrafast low-pump fluence all-optical modulation based on graphene-metal hybrid metasurfaces

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Light(Science & Applications) 2022年第5期11卷 911-924页

作者： ali Basiri md.Zubair Ebne Rafique Jing Bai Shinhyuk Choi Yu Yao School of Electrical Computer and Energy EngineeringArizona State UniversityTempeAZUSA Center for Photonic Innovation Arizona State UniversityTempeAZUSA

Graphene is an attractive material for all-optical modulation because of its ultrafast optical response and broad spectral ***,all-optical graphene modulators reported so far require high pump fluence due to the ultrashort photo-carrier lifetime and limited absorption in *** present modulator designs based on graphene-metal hybrid plasmonic metasurfaces with highly enhanced light-graphene interaction in the nanoscale hot spots at pump and probe(signal)*** on this design concept,we have demonstrated high-speed all-optical modulators at near and mid-infrared wavelengths(1.56μm and above 6μm)with significantly reduced pump fluence(1–2 orders of magnitude)and enhanced optical *** near-infrared pump-probe measurement results suggest that the modulators’response times are ultimately determined by graphene’s ultrafast photocarrier relaxation times on the picosecond *** proposed designs hold the promise to address the challenges in the realization of ultrafast all-optical modulators for mid-and far-infrared wavelengths.

关键词： pump optical modulator

Morphological and Genetical Variability among Rhizoctonia solani Isolates Causing Sheath Blight Disease of Rice

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Rice science 2016年第1期23卷 42-50页

作者： Zakiah Rahman MONI md.Ansar ali md.Shahidul ALAM md.Asif RAHMAN md.Rejwan BHUIYAN md.Salim MIAN Khandakar md.IFTEKHARUDDAULA md.Abdul LATIF Mohammad Ashik Iqbal KHAN Plant Breeding Division Bangladesh Rice Research Institute Director Research Bangladesh Rice Research Institute Department of Botany Rajshahi University Department of Genetics and Plant Breeding Bangabandhu Sheikh Mujibur Rahman Agricultural University Plant Pathology Division Bangladesh Rice Research Institute

Eighteen isolates of Rhizoctonia solani collected from infected rice plants in four different locations of Bangladesh were studied by using morphological characters and molecular markers. Anastomosis study with a reference isolate confirmed that all the isolates belonged to R. solani. Significant variation was observed in sclerotial size, shape and distribution. Un-weighted pair group method with arithmetic mean dendrogram constructed based on the Gower＇s general similarity coefficient showed that these isolates were grouped into four clusters at the 0.68 similarity coefficent according to morphological characters. Cluster I was a major cluster consisting of 13 isolates, while clusters Ⅱ to Ⅳ consisted of 1 or 2 isolates. Analyses by variable number of tandem repeat and amplified fragment length polymorphism markers showed that the isolates were grouped into five and three clusters at a similarity coefficient of 0.64 and 0.69, respectively. Although most of the variability was found between isolates from different regions as expected, significant variation was observed within the isolates collected from similar agro-ecological regions. Our results suggest the presence of different races of R. solani within the same local geographic regions.

关键词： rice Rhizoctonia solani fungal variability molecular marker morphological character

Enhancing Security in Multicellular Multicast Channels Reducing Interference Power with the Best Relay Selection

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Journal of Computer and Communications 2022年第1期10卷 1-26页

作者： Shaikh Muhammad Rizwan ali md. Zahurul Islam Sarkar Department of Information and Communication Technology BUP Dhaka Bangladesh Department of Electrical and Electronic Engineering RUET Rajshahi Bangladesh

The capacity of wireless networks is fundamentally limited by interference. A few research has focused on the study of the simultaneous effect of interference and correlation, and less attention has been paid to the topic of canceling simultaneous effect of interference and correlation until recently. This paper considers a secure wireless multicasting scenario through multicellular networks over spatially correlated Nakagami-m fading channel in the presence of multiple eavesdroppers. Authors are interested to protect the desired signals from eavesdropping considering the impact of perfect channel estimation (PCE) with interference and correlation. The protection of eavesdropping is also made strong reducing the simultaneous impact of interference and correlation on the secrecy multicast capacity employing opportunistic relaying technique. In terms of the signal-to-interference plus noise ratio (SINR), fading parameter, correlation coefficient, the number of multicast users and eavesdroppers and the number of antennas at the multicast users and eavesdroppers, the closed-form analytical expressions are derived for the probability of non-zero secrecy multicast capacity and the secure outage probability for multicasting to understand the insight of the effects of aforementioned parameters. The results show that the simultaneous effects of correlation and interference at the multicast users degrade security in multicasting. Moreover, the security in multicasting degrades with the intensity of fading and the number of multicast users, eavesdroppers and antennas at the eavesdroppers. The effects of these parameters on the security in multicasting can be significantly reduced by using opportunistic relaying technique with PCE. Finally, the analytical results are verified via Monte-Carlo simulation to justify the validity of derived closed-form analytical expressions.

关键词： Correlation Interference Power Multicellular Multicast Channel Nakagami-m Fading Opportunistic Relaying Probability of Non-Zero Secrecy Multicast Capacity Secure Outage Probability for Multicasting

Unsteady Mixed Convection Slip Flow around a Stretching Sheet in Porous Medium

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Journal of Applied Mathematics and Physics 2022年第10期10卷 3016-3036页

作者： md. Aminul Islam md. Yeakub ali Romena Akter S. M. Osman Gani Department of Mathematics Chittagong University of Engineering & Technology Chattogram Bangladesh Department of Natural Science Port City International University Chattogram Bangladesh

The heat and mass transfer of unsteady MHD two-dimensional mixed convection boundary layer flow over an exponentially porous stretching sheet is presented in this paper. Multiple slip conditions, radiation, suction or blowing, heat generation or absorption along with magnetism and porous medium are incorporated. We reduce the leading equations which are partial differential equations into a family of ordinary differential equations that are non-linear using a set of similarity transformations. The resulting equations with coupled boundary conditions are solved numerically with the aid of bvp4c solver with MATLAB package. The impacts of several non-dimensional governing parameters on the flow fields such as velocity, temperature and concentration profiles along with friction coefficient, temperature gradient and concentration gradient are portrayed graphically and discussed in detail. The result indicates that the magnetic parameter decreases the skin friction coefficient. Thermal boundary layer thickness reduces with increasing radiation parameters and enhances with increasing Prandtl number. It is also observed that the thermal slip parameter depreciates the heat transfer rate and the mass slip parameter diminishes the mass transfer rate. A comparison has been made between the current results and the numerical results of previous studies and observed a very close good agreement.

关键词： Mixed Convection Porous Medium Slips Boundary Conditions Suction/Blowing

Post Thyroidectomy Assessment of Intact Parathyroid Hormone for Early Prediction of Hypocalcaemia

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International Journal of Otolaryngology and Head & Neck Surgery 2024年第2期13卷 71-84页

作者： md. Masum Billah Ripon Kumar Sarkar md. Yousuf ali Saad Zaman md. Nazmul Hasan md. Shehab Uddin md. Mosleh Uddin Kazi Shameemus Salam Farzana Binte Abedin Leera Department of Otolaryngology-Head & Neck Surgery Universal Medical College Hospital Dhaka Bangladesh Department of Otolaryngology-Head & Neck Surgery National Institute of Ear Nose and Throat Dhaka Bangladesh Shaheed Ahsan Ullah Master General Hospital Gazipur Bangladesh Department of Otolaryngology-Head & Neck Surgery Cumilla Medical College Cumilla Bangladesh Department of ENT Oncology National Institute of Cancer Research & Hospital Dhaka Bangladesh Department of ENT Outdoor Rajshahi Medical College Hospital Rajshahi Bangladesh Department of Otolaryngology-Head & Neck Surgery Bangabandhu Sheikh Mujib Medical University Dhaka Bangladesh Department of Biochemistry Delta Medical College Hospital Dhaka Bangladesh

Background: As the half-life of intact parathyroid hormone (iPTH) is very low, it reflects parathyroid insufficiency within minutes to hours after total thyroidectomy. Therefore, iPTH level assessment in the postoperative period can be used to predict the development of hypocalcaemia. The optimal time point to measure serum iPTH is important for the accurate prediction of hypocalcaemia. Aim: This paper aims to evaluate the ability of iPTH as an early predictive marker of hypocalcaemia and determine which time iPTH is more able to predict postoperative hypocalcaemia. Method: This prospective observational study was conducted in the Department of Otolaryngology-Head & Neck Surgery, BSMMU, Dhaka, from July 2020 to December 2021, with 67 patients who underwent total thyroidectomy. iPTH levels were measured on the day before the operation and at 1 hour, 4 hours, and 24 hours after the operation. *** levels were measured on the day before the operation and 1st postoperative day. All the data were compiled and sorted properly and were analyzed statistically. Results: Postoperative hypocalcaemia developed in 18 cases, with an incidence of 26.9%. Pearson correlation showed a significant correlation between postoperative iPTH at 1 hr, 4 h, and 24 hr with 1st postoperative calcium value. The Receiver operating characteristic (ROC) curve was processed for the postoperative iPTH at 1 hr, 4 h, and 24 hr. The sensitivity, specificity, cut-off value, and mean AUC found 93.9%, 94.4%, ≤14.0, 0.988;95.9%, 94.4%, ≤09.5, 0.993 and 91.8%, 94.4%, ≤11.0, 0.993 respectively. Conclusion: iPTH can be used as an early predictor of post-thy-roidectomy hypocalcaemia. 4 hr iPTH showed more sensitivity and specificity for a cut-off value near the laboratory reference range.

关键词： Total Thyroidectomy Hypocalcaemia Serum Intact Parathyroid Hormone Early Predictor of Hypocalcaemia

Correction‐enabled reversible data hiding with pixel repetition for high embedding rate and quality preservation

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IET Cyber-Systems and Robotics 2024年第3期6卷 49-61页

作者： Mohammad ali Kawser Hussain Nyeem md.Abdul Wahed School of Transportation Science and Engineering Beihang UniversityBeijingChina Department of Electrical Electronic and Communication Engineering(EECE)Military Institute of Science and Technology(MIST)DhakaBangladesh

A novel correction‐enabled Pixel Repetition(PR)‐based Reversible Data Hiding(RDH)framework,featuring a new embedding scheme is *** proposed RDH scheme uses contextually redundant block pixels,generated via PR,in a two‐phase adaptive embedding process,enhancing both image quality and data embedding ***,each 2×2 block encodes 4 bits of data using new mapping conditions that facilitate seed pixel reconstruction from remaining block pixels and provide additional embedding ***,an innovative post‐embedding error correction technique,based on 2^(k)‐bit error‐correction,minimises post‐embedding distortion,further improving image *** error correction approach augments data embedding robustness,vital for applications like medical imaging,telemedicine,and digital watermarking that requires high embedding capacity with minimum possible *** proposed scheme surpasses existing state‐of‐the‐art methods in embedding ratedistortion performance,validated through subjective and objective ***,statistical analysis,including histogram and fragility testing,confirms the scheme's potential for image authentication across diverse multimedia *** correctionenabled RDH with PR offers enhanced embedding capacity and image quality preservation,making it particularly advantageous for applications requiring robust data hiding while maintaining visual fidelity.

关键词： data assimilation vision

Bacteriological Analysis and Public Health Impact of Broiler Meat: A Study on Nalitabari Paurosova, Sherpur, Bangladesh

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Advances in Microbiology 2019年第7期9卷 581-601页

作者： md. Omar Faruque Shahin Mahmud md. Abul Munayem Razia Sultana md. Tarek Molla md. Firoz ali Muhammad Wasim Sourav Sarker Fatematuz Zuhura Evamoni Department of Biotechnology and Genetic Engineering Mawlana Bhashani Science and Technology University Santosh Tangail Bangladesh Department of Biotechnology and Genetic Engineering Noakhali Science and Technology University Sonapur Noakhali Bangladesh

Broiler meat is one of the most important protein sources for Bangladeshi people. Food-borne diseases associated with the consumption of poultry meat and its processed products are of public health concern worldwide. An investigation was conducted to assess the bacteriological quality of poultry meat from some poultry farms and its health impact on consumer of Nalitabari paurosova, Sherpur district, Bangladesh. Total 15 samples were randomly selected and collected from different poultry farms on the basis of farms level and size. Bacteriological quality of the samples was assessed by following the standard microbiological methods. The health impact was evaluated with the help of semi-structured based questionnaire of 400 peoples. The average value of TVC and TCC were found as 4.3 × 106 CFU/g and 3.6 × 104 CFU/g respectively. In this study, the prevalence of fecal coliform was recorded as 33% and the presence of E. coli in 53% samples. The mean value of Salmonella spp. of meat samples was 4.6 × 103 CFU/g. No Shigella spp., Vibrio spp. and fungal species were detected in any sample. Some selected isolates were tested for their sensitivity against some commercially available common antibiotics used in Bangladesh. E. coli was 80% resistance to Ampicillin and 90% sensitive to Ciprofloxacin whereas Salmonella spp. showed 100% resistance to Ampicillin and 80% sensitivity to Ciprofloxacin. The antibacterial activity of renowned medicinal plant Azadirachta indica was also evaluated against some multidrug resistance bacteria. The inhibitory zone of both 30% methanolic and ethanolic extracts of Azadirachta indica was 12 mm and 12.3 mm, where 40% methanolic and ethanolic extracts were 14 mm and 16.3 mm against E. coli. The 40% ethanolic extract showed the better activity between them. The plant extract has no activity against Salmonella spp.. Awareness and health impact of broiler meat was determined among the people of different sectors on the basis of educational qualificatio

关键词： Broiler Meat Total Viable Count (TVC) Total Coliform Count (TCC) Antibiotic Azadirachta indica Public Health Nalitabari