Development of Bio-based Nanocomposites for Biosensor and Indicator Applications in Smart Food Packaging

Smart food packaging based on biosensors has been attracting more and more interest to the industrial community because of the concerns of food quality and safety. A food packaging with biosensor has a scope to enable real-time monitoring of microbial breakdown products of packaged foods. Furthermore, one of the biggest challenges in implementing biosensor for smart packaging materials is the development of bio-sensing active materials that can leverage their electrical, thermal, biodegradable and other functional properties. In this regard, nanocellulose-based activated carbon (NAC) nanocomposite was developed using the activated carbon and nanocellulose gel using the casting method with their different concentrations (15% to 50% of nanocellulose corresponding to 85% to 50% activated carbon). The developed NAC nanocomposites were electrically tested via cyclic voltammetry and results showed that 30% NAC nanocomposite consisted of good electrical properties compared to 30 and 50% of NAC nanocomposite for biosensor developments. Metal nanoparticle enriched natural biopolymer has attained significant attention in the research community, because they can create high specific surface area, adsorption capability, and gas sensing properties into polymer composite or nanocomposites. Different contents of AgNPs with 10-500 ppm were synthesized with 30% NAC nanocomposite and optimized their electrical properties. The results showed that AgNPs/NAC nanocomposite with optimum 450 ppm of AgNPs contained the good electrical properties for biosensor development. The biosensor developed with optimized AgNPs/NAC nanocomposite resulted in good sensitivity and selectivity to detect microbial breakdown products as a spoilage indicator. Ammonia (NH3) is one of the microbial breakdown products that released from protein rich food products (such as meat, fish, sea foods etc.) and had a good response in monitoring meat spoilage. The developed biosensor was utilized to monitor NH3, and the sensor showed good sensitivity over the range of 5-100 ppm and selectivity to detect the NH3. Biochar is one of the carbon-based materials that belongs a high specific surface area, highly porous structure, good stability, and cost-effectiveness over other carbon items (single or multi carbon nanotubes and graphene). The activated biochar (ABC)-based composite was developed with different ABC and polylactic acid (PLA) levels and the electrical properties of the developed ABC/PLA composite was determined via cyclic and differential voltammograms (CV and DPV). The results showed that 85% ABC/PLA composite has a good electrical property for biosensor development. To improve the gas sensing properties, 85% ABC/PLA composite was further synthesized with 450 ppm of AgNPs (v/v) and casted AgNPs/ABC/PLA nanocomposite. The biosensor was developed with casted AgNPs/ABC/PLA nanocomposite and tested for ammonia over the range of 5-60 ppm. The results revealed that the sensitivity of the developed biosensor increased as the concentrations of NH3 increased over the range of 5-60 ppm. An indicator with food packaging has the ability to monitor microbial contaminations in food products. A color indicator film was developed by a film casting method using an ultrasonic suspension of nanocellulose/chitosan blends doped with methyl red synthesis followed by PLA coating (named PLA/NCM film). The color modulation of the PLA/NCM films was processed via the colorimetric device and revealed considerable color changes (ΔEs) dependent on the meat spoilage. The PLA/NCM film changed its color upon exposure to different pH buffer solutions (2−10). The total viable microbial counts (TVC) and pH of the beef sample were determined, and the findings showed that the TVC and pH increased simultaneously depending on the state of the beef spoilage

Determinants of the quality of external board evaluation in the UK

Purpose – This study examines the influence of the following on the quality of externally facilitated board evaluation: timing of adoption of external board evaluation, type of evaluators, and the independence of external facilitators. Design/methodology/approach – The statements on board evaluation in annual reports of a sample of FTSE 350 companies were content analysed to measure the quality of externally facilitated board evaluation. We then used descriptive analysis and inferential statistics to demonstrate the possible association between the timing of adoption as well as the type and independence of external facilitators, and the quality of externally facilitated board evaluation. Findings – Results reveal some effects of the timing of adoption as well as the type and independence of external facilitators on the quality of externally facilitated board evaluation. Practical implications – Shareholders should be aware of the timing of adoption as well as consider the types and independence of external facilitators, given their influence on the quality of externally facilitated board evaluation. Regulatory authorities should provide more specific guidance on what types of professional organisations can be engaged as external facilitators and on the implementation of externally facilitated board evaluation, in order to promote its quality. Originality/value – Several studies have provided theoretical accounts on how board evaluation should be conducted to ensure its effectiveness. However, there is a dearth of empirical literature, which examines the quality of externally facilitated board evaluation. This study develops a quality measure for externally facilitated board evaluation and shows the effect of the timing of adoption, types and independence of external facilitators on its quality. Our study forges ahead an institutional theorising of external board evaluation

Jute Manufacturing Sector of Bangladesh Challenges, Opportunities and Policy Options

Major objectives of the present study are : a) To understand the changes in structure and composition of jute manufacturing sector of Bangladesh and analyse economic, technological, managerial and labour related issues of the jute manufacturing sector under different regimes. b) To study economic, technological and worker related issues of jute mills currently inoperation, under the public and private sectors, in order to identify major factors responsible for their efficiencies/ inefficiencies. c) To identify opportunities and challenges that needs to be confronted by the jute manufacturing sector in the near future. d) To extract appropriate policy suggestions with a view to develop a viable and efficient jute manufacturing sector.Bangladesh, Jute Manufacturing

Corporate governance reform in a developing country : the case of Bangladesh

Bangladesh reformed its corporate governance by adopting Bangladesh Corporate Governance Guidelines-2006 (the BCGG-2006 hereafter) due to pressures from international financial institutions (IFIs). However, there is huge controversy in prior literature regarding the IFIs’ suggested reform initiatives. The thesis asks specific research questions: RQ1. Do institutional investors and bankers in Bangladesh perceive that the level of compliance with the BCGG-2006 by the investee or borrowing company influences the investment and lending decisions respectively? RQ2.1. To what extent is the BCGG-2006 implemented in form rather than in substance? RQ2.2 Is there a relationship between the nature of compliance with the BCGC-2006 and firm performance? RQ3.1. To what extent does reported compliance with the BCGG-2006, as reported in annual reports, overstate underlying compliance with the BCGC-2006? RQ3.2 Does the overstatement of compliance reported in annual reports lead to a different relative ranking of a firm’s corporate governance structure? RQ3.3 What factors influence the overstatement of compliance with the BCG-2006 in annual reports? To investigate RQ1, an inductive approach is taken and data are collected by using semi-structured interviews of investment managers and credit rating analysts. In order to examine the remaining RQs, a deductive approach is taken and data are collected: (1) by using a structured survey questionnaire addressed to company secretaries or CFOs; and (2) from annual reports and stock exchanges. With respect to RQ1, this study finds (1) strong evidence that institutional investors and bankers perceive limited impact of corporate governance mechanisms recommended by the BCGG-2006 on investment and lending decisions respectively. In order to theorise the above findings, two theories: agency theory and the theory of path dependence are contrasted. Using a grounded theory coding, this study finds that (1) companies are locked in the path of control by sponsor families and sponsor families then impede the implementation of the BCGG-2006 and (2) institutional investors and bankers lock themselves in the path of name-based and relationship-based investment and lending practices which deters consideration of corporate governance mechanisms introduced by the BCGG-2006. Very few interviewees provide an explanation consistent with the agency theory. This evidence thus points more to the theory of path dependence than to agency theory. In relation to RQ2.1, this study finds that local privately-owned companies and government-owned companies either do not comply or comply in form but not in substance with the BCGG-2006, while subsidiaries of foreign multinational companies comply in form and in substance with the BCGG-2006. The relative strength of path dependence in local privately-owned companies and government-owned companies and subsidiaries of foreign multinational companies explains these results better than agency theory. The evidence with respect to RQ2.2 provides an indication that the nature of compliance with separation of the chairman and CEO, board independence and audit committee does not have an association with firm performance in case of local privately-owned companies. However, the evidence in relation to RQ2.2 provides an indication that the nature of compliance with the corporate governance mechanisms introduced by the BCGG-2006 makes a difference in firm performance in subsidiaries of foreign multinational companies. With respect to RQ3.1, it is found that companies overstate compliance with the BCGG-2006 in annual reports. With respect to RQ3.2, this study finds that the rank of a firm’s corporate governance is different when comparing compliance with the BCGG-2006 as reported in annual reports with compliance with the BCGG-2006 as stated in the survey. With respect to RQ3.3, it is found that overstatement of compliance is more pronounced with respect to less-observable provisions of the BCGG-2006, is positively associated with control by sponsor families and is negatively associated with control by institutional investors. This evidence is again more consistent with the theory of path dependence and institutional logic than agency theory. The findings of this thesis suggest that corporate governance researchers in developing countries should consider the role of path dependence rather than agency theory exclusively. This thesis also makes a methodological contribution by investigating overstatement of compliance with the BCGG-2006. The findings of this study may also assist regulators in developing countries and the IFIs in formulating future governance guidelines for developing countries

Investigating time to first birth among women of reproductive age in Bangladesh: a survival analysis of nationwide cross-sectional survey data

Background The birth of the first child is an important turning point in a woman’s life as it is the starting point of the demanding responsibilities of motherhood and childcare. This study aimed to explore the waiting time and the significant indicators of time to the first birth of aged 15–49 years of ever-married women in Bangladesh. Methods The study considered the most recent country-representative data collected from Bangladesh Demographic and Health Survey (BDHS) in 2017/18. The log-rank test was used to assess the statistical significance of the observed difference between waiting time to first birth and various socio-economic and demographic factors. The Cox proportional hazard model is applied to identify the influential factors for waiting time to first birth. Results About 55% of the respondents’ age at their first birth was less than 18 years. More than 21% of them were 20 years and above at their first birth. Findings revealed a higher mean age at first birth in urban areas than in rural areas. Also, in Dhaka and Sylhet region, women have a higher age at first than in other regions of Bangladesh. Results show that the place of residence, region, age at first marriage, age at first sex, respondent’s education, employment status, contraceptive use, and mass media exposure were found to be statistically significant determinants of the age of respondents at the time of first birth. Findings also show that a woman from rural areas was likely to be 5% smaller in age at the time of first birth than their counterpart (aHR 1.05; 95% CI 1.01–1.10). The age at first birth of a woman in Chattogram was 24% shorter, while in Rangpur and Barishal, that age was increased by 14% and 8%, respectively. A woman with no education, primary, and secondary education had 28%, 38%, and 29%, respectively, shorter age at first birth than that of the higher educated women. Mass media unexposed women were shorter aged at first birth by 27% (aHR 1.27; 95% CI 1.10–1.47) compared to the women who were mass media exposed. Conclusion It is necessary to increase the age of mothers at first birth which may help to reduce the prevalence of child marriage in Bangladesh. The study findings will be helpful to the policymakers in identifying the gap and designing the programmes targeting the early timing of first birth to reduce child mortality as well as poor maternal outcomes which will be beneficial for achieving the Sustainable Development Goal-3 in Bangladesh

Feature Fusion Based Audio-Visual Speaker Identification Using Hidden Markov Model under Different Lighting Variations

The aim of the paper is to propose a feature fusion based Audio-Visual Speaker Identification (AVSI) system with varied conditions of illumination environments. Among the different fusion strategies, feature level fusion has been used for the proposed AVSI system where Hidden Markov Model (HMM) is used for learning and classification. Since the feature set contains richer information about the raw biometric data than any other levels, integration at feature level is expected to provide better authentication results. In this paper, both Mel Frequency Cepstral Coefficients (MFCCs) and Linear Prediction Cepstral Coefficients (LPCCs) are combined to get the audio feature vectors and Active Shape Model (ASM) based appearance and shape facial features are concatenated to take the visual feature vectors. These combined audio and visual features are used for the feature-fusion. To reduce the dimension of the audio and visual feature vectors, Principal Component Analysis (PCA) method is used. The VALID audio-visual database is used to measure the performance of the proposed system where four different illumination levels of lighting conditions are considered. Experimental results focus on the significance of the proposed audio-visual speaker identification system with various combinations of audio and visual features

Insulinoma Presenting with Psychiatric Manifestations: A Case Report

Insulinomas, the most common of pancreatic endocrine tumors, usually present with neuroglycopenic and adrenergic features. Chronic or long standing recurrent hypogycaemia can produce intellectual deterioration and neuropsychiatric manifestations. Diagnosis of insulinoma relies on clinical features along with laboratory tests and imaging investigations to aid in localization. A 32-year-old male who presented with prominent neuropsychiatric manifestations and received anti-epileptics as a case of epilepsy and was ultimately diagnosed as insulinoma is reported here. The patient experienced fasting hypoglycemia with neuropsychiatric manifestations; computerized tomography (CT scan) and magnetic resonance imaging (MRI) revealed a diffusely enhanced mass in the head area of pancreas which was histopathologically found to be an insulinoma after hand assisted laparoscopic enucleation. Surgical excision is the treatment of choice and is curative in most cases. Key words: Insulinoma; Psychiatric Manifestation.DOI: 10.3329/bsmmuj.v2i1.3710 BSMMU J 2009; 2(1): 39-4

3D Cu Pyramid Array Grown on Planar Cu Foil for Stable and Dendrite-free Lithium Deposition

Lithium metal is recognized as the anticipated anode for rechargeable batteries because of its inherent physicochemical properties. Unfortunately, the industrialization of Li metal anodes (LMAs) has been entangled in some intractable problems stemming from the uncontrollable growth of Li dendrites, which could result in the issue of short-circuit, thereby leading to cell failure. Here, a three-dimensional structured Cu pyramid array (CPA@CF) is constructed on planar Cu foil (CF) by the simple electrodeposition method. Owing to the features of large surface area and 3D porous structure, the proposed CPA@CF not only can promote Li-ion diffusion and charge transfer, but also effectively slow down the volume change of Li. Consequently, an even and steady Li plating/stripping process up to 360 h is realized using such a CPA@CF current collector. The Li@CPA@CF|LiFePO4 full cell achieves an excellent Coulombic efficiency (CE) of 99.3 % for 160 cycles at 0.3 C with a superior capacity retention of 84.2 %