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Tin(IV) complexes of formulae, [Sn(acpysme)(C6H5)2Cl], [Sn(acpysbz)(C6H5)2Cl], [Sn(acpysbz)(C6H5)Cl2] and [Sn(acpysbz)I3] (acpysme and acpysbz = anionic forms of the 2-acetylpyrazine Schiff bases of S-methyldithiocarbazate and S-benzyldithiocarbazate, respectively) have been synthesized and structurally characterized by a variety of physico-chemical techniques and X-ray diffraction measurements. In all these complexes the tin atom adopts a distorted octahedral geometry with the Schiff bases coordinating with the tin(IV) ion as uninegatively charged tridentate NNS chelating agents via one of the pyrazine nitrogen atoms, the azomethine nitrogen atom and the thiolate sulfur atom. In the [Sn(NNS)Ph2Cl] complexes, the three NNS donor atoms of the Schiff base and a chloride ion occupy equatorial positions whereas the two phenyl groups take up axial positions of a distorted octahedron. The complexes, [Sn(acapsbz)(Ph)Cl2] and [Sn(acapsme)I3] have also distorted octahedral configurations but in this case the halido ligands are in axial positions. The Schiff bases, Hacapsme and Hacapsbz and the complex, [Sn(acpysme)I3] exhibit strong cytotoxic activity against the human breast cancer cell lines, MDA-MB-231.

Background: The aim of our study was to determine whether modified Bangla version (MMSE-B) is as effective as mini mental state examination (MMSE) tool for use in Bangladeshi people. Methods: This descriptive observational study was carried out in Department of Neurology, DMCH from January 2013 to December 2013. A total 200 healthy adults (patient attendants at the clinic) who met the inclusion criteria, were interviewed using a structured questionnaire containing information on age, sex, residence, educational backgrounds and questions set at MMSE English version (MMSE-E) and modified Bangla version for MMSE-B (Figure-1). MMSE and MMSE-B both were applied in 1:1 ration. The literate people were asked whether they are comfortable to answer in English (MMSE-E) or they would like the translated form and we applied the form of MMSE (MMSE-T) according to their wish. But in other group of people the modified Bangla version (MMSE-B) was used irrespective of level of education. Result: The mean age at presentation was 58.1±7.8 and 94% were within 50-70 years of age. Male were more common (80, 66) in both the groups and most of them belonging to rural areas. MMSE-B were mostly employed on people having only primary level of education (up to class five, n=80) or no education (n=2), whereas MMSE-E were employed up on people having a level of education higher than class five (n=96). Every question in each item of cognitive domain correlated well (correlation co-efficient range from 0.801- 0.971) except the 7th (correlation co-efficient 0.418) which had higher mean score for MMSE-B than those of MMSE-E (0.90 versus 0.54). The mean score of MMSEB was greater than the mean score of MMSE-E for most of questions except the 1st question that is related to orientation of time. The mean of total score in MMSE-E and MMSE-B were 24.04 and 24.91 respectively with a correlation co-efficient of 0.940. Conclusion: MMSE-B is adaptable for use in Bangladeshi people irrespective of level of education. Bangladesh Journal of Neuroscience 2016; Vol. 32 (2): 91-97

Background: The diagnosis of ischemic stroke remains a clinical one, with confirmatory evidence obtained through neuroimaging. Analogous to the role that the creatine kinase (CK), a biochemical test may be useful in diagnosis as well as detect severity which ultimately helps in the management of acute ischemic stroke. Objective: To evaluate serum creatine kinase level and its association with severity in acute ischemic stroke patients. Methods: This cross-sectional analytic study was carried out in the Department of Neurology, BSMMU, Dhaka from January 2014 to December 2014.In this study 50 acute ischemic stroke patients were enrolled as cases. Result: In this study, 42.0% patients were female and 58% were male and their mean age was 55.96±10.93 years. According to classification by NIH Stroke score, 32% patients was found in minor stroke, 28% in moderate stroke, 26% in moderate to severe stroke and 14% in severe stroke. 80.0% patients had increased level of serum creatine kinase. In this study there is a positive correlation between NIH Stroke Score and Serum creatine kinase level (r= 0.869, p < 0.0001). Conclusion: Increase severity of acute ischaemic stroke causes increased level of serum creatine kinase. Bangladesh Journal of Neuroscience 2016; Vol. 32 (2): 52-55

1 Professor & Chair, Department of Mechanical Engineering, IUBAT – International University of Business Agriculture and Technology, Dhaka 1230, Bangladesh 2 Assistant Engineer, Zonal Repair Shop (Central Zone, Distribution), Bangladesh Power Development Board, Gazipur1710, Bangladesh 3 Assistant Director, Research and Development (Refrigeration), Walton Hi-Tech Industries Limited, Gazipur 1750, Bangladesh

BackgroundMutations in SMPX gene can disrupt the normal activity of the SMPX protein which is involved in hearing process.ObjectiveIn this study, deleterious non-synonymous single nucleotide polymorphisms were isolated from the neutral variants by using several bioinformatics tools.MethodFirstly, dbSNP database hosted by NCBI was used to retrieve the SNPs of SMPX gene, secondly, SIFT was used primarily to screen the damaging SNPs. Further, for validation PROVEAN, PredictSNP and PolyPhen 2 were used. I-Mutant 3 was utilized to analyze the protein stability change and MutPred predicted the molecular mechanism of protein stability change. Finally evolutionary conservation was done to study their conservancy by using ConSurf server.ResultsA total of 26 missense (0.6517%) and 3 nonsense variants (0.075%) were retrieved and among them 4 mutations were found deleterious by all the tools of this experiment and are also highly conserved according to ConSurf server. rs772775896, rs759552778, rs200892029 and rs1016314772 are the reference IDs of deleterious mutations where the substitutions are S71L, N19D, A29T and K54N. Loss of Ubiquitination, loss of methylation, loss of glycosylation, and loss of MoRF binding motifs are the root causes of protein stability change.ConclusionThis is the first study regarding nsSNPs of SMPX gene where the most damaging SNPs were screened that are associated with the SMPX gene and can be used for further research to study their effect on protein structure and function, their dynamic behavior and how they actually affect protein’s flexibility.

The aim of this study is to emphasize on the clinical uses of amniotic membrane (AM) in multiple ocular disorders. AM possesses many properties including promotion of epithelialization, anti-fibrotic, anti-apoptotic, anti-angiogenic properties. Epithelial wound healing on the eye surface is promoted due to several epidermal and keratocyte growth factors as well as by its anti-inflammatory and anti-scarring effects due to interleukin-10, interleukin-1 receptor antagonists and inhibition of transforming growth factor- beta (TGF-β) signal transduction by AM in the corneal and conjunctival fibroblasts respectively. It plays a crucial role by functioning as a substitute of basement membrane (BM) and as a temporary graft material. It is not only being used as an eye graft but also its extract can be used as an eye drop for corneal and external eye diseases. So its proper preparation, preservation and clinical application can bring a revolutionary change in the treatment of different ocular disorders.

The reader proteins like bromodomains have recently gained increased attentions in the area of epigenetic drug discovery, as they are the potent regulators in gene transcription process. Among the other bromodomains, cAMP response element-binding protein (CREB) binding protein or CREBBP bomodomain involved in various cancer progressions and therefore, efforts to develop specific inhibitors of CREBBP bomodomain are of clinical value. In this study, we tried to identify selective CREBBP bromodomain inhibitor, which was accomplished by using molecular docking, free energy calculation and molecular dynamics (MD) simulation studies, considering a series of naphthyl based compounds. The docking procedure was validated by comparing root mean square deviations (RMSDs) of crystallographic complex to docked complex. Favorable electrostatic interactions with the Arg1173 side chain were considered to attain selectivity for CREBBP bromodomain over other human bromodomain subfamilies. We found that naphthyl-based compounds have greater binding affinities towards the CREBBP bromodomain, and formed non-bonded interactions with various side chain residues that are important for bromodomain inhibition. From detailed investigation by induced fit docking, compound 31 was found to have favorable electrostatic interactions with the Arg1173 side chain by forming conventional hydrogen bonds. This result was further confirmed by analyzing hydrogen bond occupancy and bonding distance during the molecular dynamics simulation. We believe that these findings offer useful insight for the designing of target specific new bromodomain inhibitor and also promote further structure guided synthesis of analogues for identification of potent CREBBP bromodomain inhibitors as well as detailed in vitro and in vivo analyses. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s40203-018-0038-4) contains supplementary material, which is available to authorized users.

This paper measures the adhesion/cohesion force among asphalt molecules at nanoscale level using an Atomic Force Microscopy (AFM) and models the moisture damage by applying state-of-the-art Computational Intelligence (CI) techniques (e.g., artificial neural network (ANN), support vector regression (SVR), and an Adaptive Neuro Fuzzy Inference System (ANFIS)). Various combinations of lime and chemicals as well as dry and wet environments are used to produce different asphalt samples. The parameters that were varied to generate different asphalt samples and measure the corresponding adhesion/cohesion forces are percentage of antistripping agents (e.g., Lime and Unichem), AFM tips K values, and AFM tip types. The CI methods are trained to model the adhesion/cohesion forces given the variation in values of the above parameters. To achieve enhanced performance, the statistical methods such as average, weighted average, and regression of the outputs generated by the CI techniques are used. The experimental results show that, of the three individual CI methods, ANN can model moisture damage to lime- and chemically modified asphalt better than the other two CI techniques for both wet and dry conditions. Moreover, the ensemble of CI along with statistical measurement provides better accuracy than any of the individual CI techniques.

Surgical procedures always involve an element of risk and even a minor error can lead to serious complications. Recent data suggests that over 200 million surgeries are performed annually worldwide and about 3 to 22% of these surgeries involve some sort of complications. Surgical errors can be caused by both technical errors and cognitive errors which may happen to even an experienced surgeon. However, resident surgeons are more prone to surgical errors as they start their surgical career with less experience and skills. In order to reduce errors and accelerate the learning experience of surgeons, we propose a method that can identify, model and prevent surgical errors by using biomechanical motion analysis and a high-fidelity 3-D surgery simulator., submitted to the 42nd Annual Meeting of the American Society of Biomechanics held at Mayo Clinic, Rochester, MN, USA (ASB 2018).

Molecular recognition in water is challenging but water-soluble molecularly imprinted nanoparticle (MINP) receptors were produced readily by double cross-linking of surfactant micelles in the presence of suitable template molecules. When the micellar surface was decorated with different polyhydroxylated ligands, significant interactions could be introduced between the surface ligands and the template. Flexible surface ligands worked better than rigid ones to interact with the polar moiety of the template, especially for those template molecules whose water-exposed surface is not properly solvated by water. The importance of these hydrophilic interactions was examined in the context of different substrates, density of the surface ligands, and surface-cross-linking density of the MINP. Together with the hydrophobic interactions in the core, the surface hydrophilic interactions can be used to enhance the binding of guest molecules in water.

Background: Heavy metals may produce various symptoms among the exposed, of which polyneuropathy is a matter of real concern. Our aim was to determine the pattern and association between polyneuropathy and blood lead level. Methods: This case control study was done in the department of Neurology, Bangabandhu Sheikh Mujib Medical University, Dhaka in collaboration with Bangladesh Atomic Energy Centre from July 2001 to June 2002. The lead concentration in the blood was detected by Xray fluorescence (XRF) technique. Nerve conduction study and CSF examination were done among the cases. Result: Data were collected from 92 respondents, of whom cases and controls were equal in number with a male to female ratio of 8.17:1. Mean age of the cases and controls were 30.87 +14.53 years and 30.91+ 12.03 years respectively. Among the cases, 55% had sub acute type of polyneuropathy, followed by acute and chronic type of polyneuropathy among 30% and 15% respondants respectively. The mean CSF protein level was 112.00 + 65.04 gm/L. The mean CSF protein was higher in acute polyneuropathy than in subacute and chronic cases (p

Design and synthesis of organic chelating agents containing nitrogen and sulfur as donor atoms and their metal complexes is an interesting field of research for their different types of activities. The bi-dentate N,N chelating agent such as 2,2-Bipyridal has been playing a vital role in synthetic and medicinal chemistry. 2,2-Bipyridal has been used to prepare many mixed-ligand complexes. Different ligand complexes prepared from 2,2-Bipyridyl are used in different areas such as molecular catalysis, solar energy conversion, calorimetric analysis, herbicides, molecular recognition, self-assembly, antineoplastic agents, and nucleic acid probes. Another important property of these types of compounds is the triplet state photosensitizing character of bipyridyl nucleus, which is shown in metal complexes. It is also found that compounds containing O,S,N atoms have received considerable attention because of their pharmacological studies like anticancer, antibacterial, and antitumour activities. Therefore, it has been decided to synthesize Schiff bases derived from 2,2’- bipyridyl-5,5’-dicarbaldehyde compounds with O,S,N and F-containing amines and study their antibacterial properties. Several new Schiff bases have been synthesized and fully characterized by spectral data. This paper presents the synthesis and characterization of newly designed Schiff bases.

Introduction Invasive infections caused by Salmonella enterica serovar Typhi and Paratyphi A are estimated to account for 12–27 million febrile illness episodes worldwide annually. Determining the true burden of typhoidal Salmonellae infections is hindered by lack of population-based studies and adequate laboratory diagnostics. The Strategic Typhoid alliance across Africa and Asia study takes a systematic approach to measuring the age-stratified burden of clinical and subclinical disease caused by typhoidal Salmonellae infections at three high-incidence urban sites in Africa and Asia. We aim to explore the natural history of Salmonella transmission in endemic settings, addressing key uncertainties relating to the epidemiology of enteric fever identified through mathematical models, and enabling optimisation of vaccine strategies. Methods/design Using census-defined denominator populations of ≥100 000 individuals at sites in Malawi, Bangladesh and Nepal, the primary outcome is to characterise the burden of enteric fever in these populations over a 24-month period. During passive surveillance, clinical and household data, and laboratory samples will be collected from febrile individuals. In parallel, healthcare utilisation and water, sanitation and hygiene surveys will be performed to characterise healthcare-seeking behaviour and assess potential routes of transmission. The rates of both undiagnosed and subclinical exposure to typhoidal Salmonellae (seroincidence), identification of chronic carriage and population seroprevalence of typhoid infection will be assessed through age-stratified serosurveys performed at each site. Secondary attack rates will be estimated among household contacts of acute enteric fever cases and possible chronic carriers. Ethics and dissemination This protocol has been ethically approved by the Oxford Tropical Research Ethics Committee, the icddr,b Institutional Review Board, the Malawian National Health Sciences Research Committee and College of Medicine Research Ethics Committee and Nepal Health Research Council. The study is being conducted in accordance with the principles of the Declaration of Helsinki and Good Clinical Practice. Informed consent was obtained before study enrolment. Results will be submitted to international peer-reviewed journals and presented at international conferences. Trial registration number ISRCTN 12131979. Ethics references Oxford (Oxford Tropical Research Ethics Committee 39-15). Bangladesh (icddr,b Institutional Review Board PR-15119). Malawi (National Health Sciences Research Committee 15/5/1599). Nepal (Nepal Health Research Council 306/2015).

Among the conventional flow measuring instruments orifice plate is the cheapest but its co-efficient of discharge (Cd) is lower than that of the others. In the present investigation, the performance of nozzle plates were compared with that of orifice plates at different area ratios and Reynolds numbers and were found to produce higher (Cd) while maintaining the same manufacturing cost.

Okra bahmia (Abelmoschus esculentus) plant is considered as one of the abundant sources of natural fibers. Huge amount of okra plant stem is discarded on the field annually after collecting vegetable, without proper utilization. However, this biomass from the okra plant is a renewable, biodegradable, cost efficient and low-density source for production of bast fibers, and other industrial cost-efficient eco-friendly materials. The research on okra bast fiber has started in 2007. After that, the fiber extraction process, composition of fiber, morphology and performance properties of fiber, fiber modification techniques, and some important applications of the fiber etc. have been established. It was found that the okra bast fiber contains high cellulose content, excellent mechanical strength and stiffness, and good thermal resistance which are comparable to some traditional bast fibers like jute, hemp and ramie. Some okra bast fiber reinforced biocomposites were successfully fabricated with different matrices including biodegradable corn starch, Poly(lactic acid), P(vinyl alcohol), urea formaldehyde resin etc. via application of various processing methods. These studies revealed that the okra bast fiber biocomposites exhibited better mechanical properties, water resistance and thermal properties at optimized processing conditions. Therefore, by suitably optimizing the fiber, matrix, processing conditions, the future expectations of the okra bast fibers can be dramatically enhanced and its usage in composite field can be widened. © Springer International Publishing AG 2017.

not available Bangladesh Journal of Neuroscience 2014; Vol. 30 (2): 112-116

New methods for the synthesis of 1,3,4-oxadiazole and 1,3,4-thiadiazole have been described. No cyclizations took place in the absence of ZnCl 2 . 1,3,4-Thiadiazoles are formed in the presence of ZnCl 2 alone, whereas oxadiazoles are produced when a base such as Et 3 N or KOH was used along with ZnCl 2 . % Yields are optimized.

The Schiff bases formed by condensation of S-methyl- and S-benzyldithiocarbazate with 2-pyridinecarboxaldehyde react with zinc(II) and cadmium(II) acetates to form stable metal complexes of general formulas, [Zn(NNS)(CH3COO)]2 and [M(NNS)2] (M = Zn2+, Cd2+; NNS− = anionic forms of the 2-pyridinecarboxaldenhdye Schiff bases of S-methyl- and S-benzyldithiocarbazate, respectively) which have been characterized by a variety of physico-chemical techniques and X-ray crystallographic structure analysis. The complexes, [Zn(NNS)(CH3COO)]2 are acetate anion-bridged centrosymmetric dimers in which each of the Schiff bases is coordinated to the zinc(II) ions as a uninegatively charged NNS tridentate chelating agent coordinating via the pyridine nitrogen atom, the azomethine nitrogen atom and the thiolate sulfur atom. The acetate anion acts as a bridging bidentate ligand coordinating with the two zinc atoms in a syn–syn manner. Each zinc(II) ion in the dimer adopts an approximately square-pyramidal geometry. The bis-ligand complexes, [M(NNS)2] (M = Zn2+, Cd2+) have distorted octahedral structures in which the two anionic Schiff bases are coordinated to the metal ions meridionally as NNS tridentate chelating agents via the pyridine nitrogen atom, the azomethine nitrogen atom and the thiolate sulfur atom. Both the mono- and bis-ligand zinc(II) complexes exhibit strong cytotoxic activity against the HELA (human cervical cancer) cell lines. Some of these compounds exhibit stronger cytotoxicity against HELA than the commercially important anticancer drug, Tamoxifen.

Purpose: Drug resistance is a burning issue in bacterial kingdom and in appropriate use of antibiotics is one of the most important factors that could affect the increasing patterns of resistance. The aim of the present study is to ascertain the current situation of growing antibiotic resistance against bacteria, ex-gram positive cluster forming cocci. Materials and Methods: Various clinical samples such as pus, sputum, throat swab, high vaginal fluid, prosthetic swab, wound swab, ear swab were taken from776 subjects and cultured on nutrient agar and Mac Conkey's agar. After morphological identification 271 isolates were tested for antimicrobial susceptibility testing. Results: In this study, Antibiotic susceptibility testing was done by using 271 patients sample out of 363 positive growth culture which was collected from pus. It stated that male and female ratio for infection was 1:0.6 and resistance are high in the age group 21-40 years. Observation of susceptibility test indicate that ampicillin,amoxycillin and co-trimoxazole showed increase rate of resistance which were 28, 21 and 15% respectively. On the other hand, cefuroxime and ceftriaxone showed significantly sensitive which belongs to cephalosporin second and third generation group. Conclusion: It is very important to reduce frequent misuse; inadequate dosages and easy availability of antimicrobials to keep away human generation from emerge of antibiotic resistance.

BACKGROUND CONTEXT Pseudarthrosis or nonunion of the cervical spine is the result of failed attempted fusion and is a leading cause of postoperative axial pain and radiculopathy. Reported rates of failed cervical fusion range from 4.4 to 50%, generally higher with multilevel procedures, and pseudarthrosis accounts for 45%–56% of revision surgeries. Nonunion is difficult to detect clinically and diagnosis is based solely on symptomatology (neck pain, radiculopathy) and imaging studies. The gold standard approach to define fusion status involves surgical exploration, a last resort option. Radiographic tools are commonly used first, with computed tomography (CT) considered the most reliable method. However, CT scans are expensive and expose patients to large radiation doses (hundreds of times more than standard X-ray). The status of anterior cervical fusion can also be determined using interspinous motion analysis; the goal is to detect any movement between adjacent vertebra using dynamic radiographs. This may be accomplished by measuring the distance between the tips of adjacent spinous processes on lateral flexion and extension films. However, the technique is subjective and affected by parallax, and studies have found wide interobserver differences. This makes it difficult to accurately apply the method to assess pseudarthrosis using the proposed cutoff values (1 or 2 mm). Other literature similarly suggests that current radiographic methods do not reliably provide clinical information about abnormalities of intervertebral motion. Therefore quantitative and standardized methods for defining spinal fusion or instability are needed. PURPOSE Our hypothesis is that intervertebral motion can be more accurately detected using a simple passive implantable device that responds to the pressure differential or vertebral body endplate motion within the index disc space between the flexed and extended positions of the cervical spine. Conceptually, this dynamic motion sensor could detect and potentially prevent pseudarthrosis, a leading cause of postoperative pain and radiculopathy STUDY DESIGN/SETTING This desktop and benchtop research was conducted primarily in a chemistry laboratory. Manufacturing of prototypes and other materials was performed on-site. Radiographic images were taken at a centralized animal research facility. METHODS A cervical interbody spacer with integrated fluidic pressure sensor was developed using CAD modeling software and prototyped with 3D printing. The working principal involves a fluid well and indicator channel. The spacer was placed between Sawbones vertebra analogs and loads applied to simulate dynamic spinal positions. Previous work with a similar fluidics device used a single-column compression tester to apply loads comparable to those experienced by vertebra in the cervical region. Radiographs were also taken of a device loaded with radio-dense fluid (cesium acetate) and channel diameter of 0.5mm. RESULTS Computer simulations suggested that the device would fit and function well between cervical vertebra in the flexed and extended spinal positions. Prototypes placed between cervical bone analogs under load demonstrated that the signal would be apparent clinically. Previous work showed that fluid displacement into the indicator portion was in the appropriate scale (0–6.9 mm) under applied loads in the range experienced clinically (0–110 N); this relationship was linear and repeatable. The imaging resolution of the device with a radiocontrast agent as the indicator fluid was also within the clinical range, and the signal was apparent on radiographs. CONCLUSIONS Based on these results it appears that an interbody device with fluidic sensor is potentially a viable option for assessing fusion status in the cervical spine.Prior literature gives the range of loads expected in the cervical spine (up to ≈100N). Articles describing interspinous motion analysis suggest sufficient bone growth (fusion) occurs when the distance between the tips of adjacent cervical spinous processes changes by less than 1 mm or 2 mm between flexion and extension. Our concept offers two primary advantages over existing techniques. First, the indicator channel provides a clear and distinct signal or marker that can be plainly read on radiographs, simplifying comparisons between the flexed, neutral and extended positions and enabling monitoring over time. Second, the device introduces gain proportional to the ratio of the cross-sectional areas of the fluid well and channel, providing amplification and enabling detection of smaller changes. While a priori research demonstrated that an implantable fluidic device responded appropriately under the range of applied physiologic loads, if needed additional gain could be introduced by increasing this ratio. Future work involving finite element analysis and mechanical testing is underway and ultimately a cadaveric study will be conducted to verify the loads and characterize the device in vitro.Limitations of this work include the material choice as all prototypes were created using 3D printing. The flexural modulus of the material is important, and the device may potentially be formed with polycarbonate urethane, a stiffer and tougher flexible material commonly used in cervical disc replacements.

GBS is an immune mediated polyradiculoneuropathy classically characterized by acute symmetrical ascending lower motor type weakness and areflexia. But sometimes, in axonal variants of GBS, reflexes are preserved or exaggerated. We report a case of GBS with bilateral extensor plantar response during the course of the disease. A 36- year-old male presented with acute quadriplegia with asymmetrical muscle weakness and extensor plantar response. Sensory, bowel and bladder function was intact. He was treated with intravenous methylprednisolone daily for 5 days without improvement. NCS revealed AIDP and AMAN variants of GBS. So, in any patient presenting with acute quadriplegia with extensor plantar response, GBS should be considered as differential diagnosis. Bangladesh Journal of Neuroscience 2015; Vol. 31 (1): 42-44

In this paper, we developed several kinds of ordered structures in hydrogels with different geometries and sizes by harnessing heterogeneous swelling induced mechanical instability, i.e., surface creasing, which leads to molecular orientations along the tensile direction. These hydrogels were synthesized by polymerization of a cationic monomer, N-[3-(N,N-dimethylamino)propyl] acrylamide methyl chloride quaternary (DMAPAA-Q) and a chemical cross-linker, in the presence of a small amount of the semirigid polyanion, poly(2,2′-disulfonyl-4,4′-benzidine terephthalamide) (PBDT), as dopant. During the swelling process of as-prepared gels, surface creasing occurs and induces formation of a lattice-like periodic ordered structure, which is maintained in the swollen gels due to the formation of strong polyion complex. Besides this structure formed at the central part of gel sheets, PBDTs align parallel to the gel boundary at the edge of gels with a cuboid, disk, or ring shape. The size of the two regions with diffe...

Four new Schiff bases of 1,10-phenanthroline-2,9-dicarboxaldehyde with sulfur-containing amines such as 2-mercaptoaniline, S-alkyl/aryl dithiocarbazates and thiosemicarbazide have been synthesized and characterized by spectroscopic and X-ray crystallographic techniques. A comparative study of the methods of synthesis has been made using both traditional and microwave techniques. A significant reduction in reaction time has been observed when the microwave method was used. In some of the reactions, the yields also increased significantly.

Abundant, low prices and a highly reduced nature make glycerol to be an ideal feedstock for the production of reduced biochemicals and biofuels. Escherichia coli has been paid much attention as the platform of microbial cell factories due to its high growth rate (giving higher metabolite production rate) and the capability of utilizing a wide range of carbon sources. However, one of the drawbacks of using E. coli as a platform is its mixed metabolite formation under anaerobic conditions. In the present study, it was shown that ethanol could be exclusively produced from glycerol by the wild type E. coli, while d-lactic acid could be exclusively produced from glucose by pflA.cra mutant, where the glucose uptake rate could be increased by this mutant as compared to the wild type strain. It was also shown that the growth rate is significantly reduced in pflA.cra mutant for the case of using glycerol as a carbon source due to redox imbalance. The metabolic regulation mechanisms behind the fermentation characteristic were clarified to some extent.

Expression of heat shock proteins (Hsps) synthesized by bacterium (Pseudomonas spp.) during stress condition (elevated temperature) is identified and studied their association in adaptation to environmental extremes. Collection, screening, isolation and identification of zoom land soil bacterium were carried out by growing bacterial cells on selective Agar Cetrimide media. Optimization of culture conditions (incubation time and temperature) for the maximum production of cell (Dry Cell Weight) also considered for the identified organism (Pseudomonas spp.) in LB media during micro-aerobic batch culture; where maximum cell growth was found 1.80 gm/L at 10 hours incubation period and 37°C incubation temperature, while rpm was 120. Subsequently, bacterial cell was grown in LB media for 6 hours at 37°C and 120 rpm into shaking incubator, then incubated for 2 hours, where maximum cell growth was observed 2.38 ± 0.06 gm/L during elevated temperature (50°C), stimulated by heat shock proteins. Then different intracellular and extracellular soluble protein extraction, purification was attempted from soil bacterium by centrifugation, sonication, repeated freezing and thawing. SDS-PAGE was performed for the separation of heat shock protein, where protein bands intensity 90, 84, 70 and 45 kDa were found according to their molecular weight. Pseudomonas spp. can produce heat shock protein during harsh condition which can help them to survive by effective adaptation mediated by universal regulatory mechanisms affecting several pathways. Hsps are expected to play a significant role to conferring tolerance in response to changes in high temperature. They are also responsible for survival of bacterial cells and increasing soil fertility which associated with virulence. So, this study will help to understand the impact of soil microorganisms to revive the soil fertility though people burn their paddy fields after harvesting in zoom areas of Bangladesh.

The Aggregate Production Planning (APP) is a schedule of the organization’s overall operations over a planning horizon to satisfy demand while minimizing costs. It is considered as the baseline for any further planning and formulating the master production scheduling, resources, capacity and raw material planning. For APP of Cement Company, a large number of optimization criteria- regular time production, overtime production and inventory level of cement, clinker, limestone, gypsum and subsidiary ingredients play a very important role. Complexities have arisen when practitioners try to balance these large numbers of constraints during the planning horizon. In this research work, authors try to construct a mathematical model that reduces complexities and makes an effective balance among different constraints. The model then solved by well-known heuristics algorithm named particle swarm optimization (PSO) and compare the result among various types of PSO algorithm. Authors also find out the limitations of PSO to solve APP problem.

This study demonstrates the applicability of satellite-based radar altimeter flood forecasting in downstream flood prone areas of Bangladesh without the use of data assimilation. The joint NASA-French satellite mission JASON-2 provides water level elevation data over the Ganges-Brahmaputra-Meghna (GBM) basin at no cost to end users. A nearly linear relationship was established between these upstream water elevation observations with the downstream water levels in Bangladesh especially in the Ganges and Brahmaputra basins. Using this remotely sensed data as boundary inflow in the current flood forecasting model developed by the Flood Forecasting and Warning Center (FFWC; see FFWC 2014) within the Bangladesh Water Development Board (BWDB), it is possible to generate a 5 day or more flood forecast in some downstream locations with considerable accuracy. This approach was validated using remotely sensed JASON-2 observations from 2014 and comparing the resulting flood forecast with recorded ground measurements of river height. This study highlights the potential of using JASON-2 data for flood forecasting on international rivers like in Bangladesh where upstream hydrologic observations are otherwise unavailable.

Wind tunnel is a device, by artificially producing airflow relative to a stationary body that measures aerodynamic force and pressure distribution to simulate with actual conditions. Wind Tunnels offer a rapid, economical, and accurate means for aerodynamic research. The most important aspect of wind tunnels is their ability to accurate recreate the full complexity of full fluid flow. In the current study, a low cost subsonic wind tunnel is designed, constructed and its performance is tested. The main focuses were to reduce the cost of construction and to erect it in a laboratory room. The cross section of the wind tunnel is of square type with dimension 0.90 m × 0.90 m and the length of the section is 1.35 m. The overall length of the tunnel is about 7.35 m which can be erected in a laboratory room. After testing the performance of the tunnel it is found that the maximum wind velocity inside the wind tunnel test section is about 28 m/s and the velocity profile along the height and width of the test section is almost linear in nature excluding the approximately 12% allowance in four side walls where boundary layer if formed. The constructed wind tunnel was conformed to the design and can be used for different test in the field of aerodynamics. Keywords --Subsonic Wind Tunnel, Low Cost, Test Section, Aerodynamics, Fluid Flow, Velocity Profile

The main subject of this work is the vortex generator control of flow separation on a deflected simple flap of a NACA 63A421 airfoil. The investigation was carried out using experimental and numerical methods. In the first step non-control case was solved by means of numerical simulation to determine the location of flow separation and airfoil boundary layer thickness. Information obtained from the numerical calculations was utilized for vortex generator (VG) design according to Godard, Stanislas, who dealt with vortex generator flow control on a bump and Lin. VGs were then applied to the flapped airfoil and their influence on flow was investigated using tuft filaments visualization technique. This experimental part was carried out in closed circuit wind tunnel o f t h e K h u l n a u n i v e r s i t y o f E n g i ne e r i n g & T e c h n o l o g y ( K U E T . All numerical simulations presented in this paper were calculated using commercial code Fluent.

Cohesive Zone Modeling (CZM) is one of the most promising tools to investigate nonlinear crack propagation in present time. In this study, CZM approach is used to investigate the influence of various type of loading parameters in nonlinear crack propagation. These parameters include loading velocity, mass scaling, maximum strength of cohesive element and displacement jump. For this investigation, we used DYNA3D as a dynamic crack simulation code. Simulation outcomes were compared with the experimental results, where an experimental observation for Arcan test Mode I case was made in MTS machine. Note that, the experiment was performed in quasi-static mode. As DYNA3D is used to simulate dynamic crack propagation, this comparison reflects the deviation of crack parameters for quasi-static and dynamic crack propagation. Finally we checked, whether DYNA3D can be used for quasi-static crack propagation or not.

Isatin, 5-chloroisatin, 7-bromoisatin and 7-ethylisatin on treatment with furan in presence of diethylamine yield furan moiety inclusion products bis-diisatin [3,3´] furan, bis-[5,5´] dichlorodiisatin [3,3´] furan, bis-[7,7´] dibromodiisatin [3,3´] furan and bis-[7,7´] diethyldiisatin [3,3´] furan respectively in moderate yields. The cytotoxicity of these compounds was studied by the brine shrimp lethality bioassay and the Structure Activity Relationships (SAR) of these compounds has been discussed. The present study shows that the compound bis-[7,7´] dibromodiisatin [3,3´] furan had pronounced cytotoxicity whereas compounds bis-[5,5´] dichlorodiisatin [3,3´] furan and bis-[7,7´] diethyldiisatin [3,3´] furan were moderately active. It is remarkable that the constituent, Y = -Br at seven position in the benzene ring has greater activity than ethyl and chlorine atom.

Tissue Banking and Biomaterial Research Unit (TBBRU), the only tissue bank of Bangladesh, has been established to create an available supply of human tissue allografts for transplantation in Bangladesh. Since its establishment in 2003, TBBRU strictly follows the guidelines of tissue banking setup by the International Atomic Energy Agency, the European Association of Tissue Banks and the American Association of Tissue Banks. Though started serving from earlier, regular supply of tissue allografts from this bank were documented at the end of 2006. From January 2007 to December 2014, 3747 bones and 5772 amniotic sacs were collected from live tissue donors. During this period, 59,489 cc bone allografts and 23,472 pieces of amniotic membrane allografts were processed. In the same period, 58,483 cc bone allografts and 20,786 pieces membrane were supplied to different hospitals throughout the country on the basis of demand. The outcomes of the concerted efforts of tissue banking professionals and physicians were the restoration of health and hope of 3662 patients during the last 8 years.

Free convective heat transfer from a heated slender body in a rectangular channel is studied in the present work. Numerical investigation has been carried out to study the fluid flow and heat transfer characteristics in a channel with heated slender body placed at the middle. The walls are assumed to be adiabatic and entrainment is provided from the environment through the openings of the channel. The two dimensional Continuity, Navier-stokes and Energy equation with Boussinesq approximation have been solved by finite difference method. Uniform grids are used in entire computational domain. The differential equations are discritized using central difference method and forward difference method. The discritized equations with proper boundary conditions are sought by SUR method. The flow field has been studied for the range of 50.0< Ra range of Prandtl Number considered., A project report submitted to the Department of Mechanical Engineering, Khulna University of Engineering and Technology, in partial fulfillment of the requirements for the degree of "Bachelor of Science" in Mechanical Engineering

This paper proposes an approach to detect emotion from human speech employing majority voting technique over several machine learning techniques. The contribution of this work is in two folds: firstly it selects those features of speech which is most promising for classification and secondly it uses the majority voting technique that selects the exact class of emotion. Here, majority voting technique has been applied over Neural Network (NN), Decision Tree (DT), Support Vector Machine (SVM) and K-Nearest Neighbor (KNN). Input vector of NN, DT, SVM and KNN consists of various acoustic and prosodic features like Pitch, Mel-Frequency Cepstral coefficients etc. From speech signal many feature have been extracted and only promising features have been selected. To consider a feature as promising, Fast Correlation based feature selection (FCBF) and Fisher score algorithms have been used and only those features are selected which are highly ranked by both of them. The proposed approach has been tested on Berlin dataset of emotional speech [3] and Electromagnetic Articulography (EMA) dataset [4]. The experimental result shows that majority voting technique attains better accuracy over individual machine learning techniques. The employment of the proposed approach can effectively recognize the emotion of human beings in case of social robot, intelligent chat client, call-center of a company etc.

Retron is a retroelement that encodes msDNA (multicopy single-stranded DNA) which was significantly found mainly in Gram-negative pathogenic bacteria. We screenedYersinia frederikseniiATCC 33641 contig01029 for the presence of retroelement by using bioinformatics tools and characterized a novel retron-Yf79 on the chromosome that encodes msDNA-Yf79. In this study, we perceived that, the codon usage of retron-Yf79 were noteworthy different from those of theY. frederikseniigenome. It demonstrates that, the retron-Yf79 was a foreign DNA element and integrated into this organism genome during their evolution. In addition to this, we have observed a transposase gene which is located just downstream of retron-Yf79. So, the enzyme might be responsible for the transposition of this novel retron element.

This paper describes a recurrent neural network (RNN) based phoneme recognition method incorporating articulatory dynamic parameters (Δ and ΔΔ). The method comprises three stages: (i) DPFs extraction using a recurrent neural network (RNN) from acoustic features, (ii) incorporation of dynamic parameters into a multilayer neural network (MLN) for reducing DPF context, and (iii) addition of an Inhibition/Enhancement (In/En) network for categorizing the DPF movement more accurately and Gram-Schmidt orthogonalization procedure for decorrelating the inhibited/enhanced data vector before connecting with a hidden Markov models (HMMs)-based classifier. From the experiments on Japanese Newspaper Article Sentences (JNAS), it is observed that the proposed method provides a higher phoneme correct rate over the method that does not incorporate dynamic articulatory parameters. Moreover, it reduces mixture components in HMM for obtaining a higher performance.

A rigorous theoretical analysis is presented to show that moisture extraction from air is possible using a nonuniform electric field. If the atmospheric moisture is extracted and accumulated in an extraction chamber, the humidity will gradually increase. When the humidity reaches 100%, any further attempt to increase the moisture enrichment in the moisture extraction chamber will result in the condensation of the water molecules, releasing their latent heat of condensation. This can be a very attractive source for pollution-free energy. A formulation is developed to calculate the percentage of moisture extraction considering all the thermodynamic limitations, like diffusion and thermal agitation of the gas molecules. A simple experiment was performed to establish the theory. Two identical chambers were used by extracting moisture from one to enrich the other. Very good agreement between the theory and experimental results was obtained.

In the title compound, C16H8N6O2S2·2C2H6OS, the phenanthroline molecule resides on a twofold axis, and the asymmetric unit also contains a slightly disordered [occupancy ratio for S atom of 0.95 (3):0.047 (3)] molecule of dimethyl sulfoxide. The O atoms of the solvent molecule accept hydrogen bonds from the N—H groups of the five-membered 2,3-dihydro-1,3,4-oxadiazole-2-thione ring. This ring is nearly coplanar with the phenanthroline ring, with a dihedral angle between their least-squares planes of 8.86 (6)°. In the crystal, the molecules are linked by C—H...O interactions.