Blocking performance of extended pruned vertically stacked optical banyan structure under different link failure conditions

The blocking performance of extended pruned vertically stacked optical banyan (VSOB) networks under different link failure conditions has been analyzed in this paper. We applied plane fixed routing with linear search and plane fixed routing with random search algorithms to route the optical data through the network in our simulation. Our simulation results show that adding one or two extra planes to the pruned VSOB network reduces the blocking probability significantly. Beyond two extra planes, the decrease of blocking probability is not so significant. A close approximation of the minimum number of planes required to make the extended pruned vertically stacked optical banyan networks nonblocking has been presented

Ongoing WTO Negotiations and Bangladesh’s Interests: Insights from CPD’s October 2002 Tracking Mission to Geneva

The paper is based on the participation of CPD delegation in Geneva and gives an insight into the particular issue of priority interest to Bangladesh in the context of the ongoing negotiations including GATS, AoA, TRIPS and Market Access.The paper provides an understanding about the important implications of the ongoing Doha Development Round negotiations for Bangladesh and other least developed countries (LDCs) both in terms of accessing the opportunities emanating from the evolving global trading system, and also from the perspective of addressing the attendant challenges.WTO-General Council, Tracking Mission, Geneva, Bangladesh

Novel application of electrochemical bipolar exfoliated graphene for highly sensitive disposable label-free cancer biomarker aptasensors

Label-free aptasensors can be a promising point-of-care biosensor for detecting various cancer diseases due to their selectivity, sensitivity, and lower cost of production and operation. In this study, a highly sensitive aptasensor based on gold-covered polyethylene terephthalate electrodes (PET/Au) decorated with bipolar exfoliated graphene is proposed as a possible contender for disposable label-free aptasensor applications. Bipolar electrochemical exfoliation enables simultaneous exfoliation, reduction, and deposition of graphene nanosheets on prospective electrodes. Our comparative study confirms that the bipolar exfoliated graphene deposited on the negative feeding electrode (i.e., reduced graphene oxide) possesses better electrochemical properties for aptasensing. The optimized aptasensor based on bipolar exfoliated graphene deposited on PET/Au electrodes exhibits a highly sensitive response of 4.07 μA log c−1(unit ofc, pM) which is linear in the range of 0.0007-20 nM, and has a low limit of detection of 0.65 pM (S/N = 3). The aptasensor establishes highly selective performance with a stability of 91.2% after 6 days. This study demonstrates that bipolar electrochemistry is a simple yet efficient technique that could provide high-quality graphene for biosensing applications. Considering its simplicity and efficiency, the BPE technique promises the development of feasible and affordable lab-on-chip and point-of-care cancer diagnosis technologies

Online power quality disturbance detection by support vector machine in smart meter

Power quality assessment is an important performance measurement in smart grids. Utility companies are interested in power quality monitoring even in the low level distribution side such as smart meters. Addressing this issue, in this study, we propose segregation of the power disturbance from regular values using one-class support vector machine (OCSVM). To precisely detect the power disturbances of a voltage wave, some practical wavelet filters are applied. Considering the unlimited types of waveform abnormalities, OCSVM is picked as a semi-supervised machine learning algorithm which needs to be trained solely on a relatively large sample of normal data. This model is able to automatically detect the existence of any types of disturbances in real time, even unknown types which are not available in the training time. In the case of existence, the disturbances are further classified into different types such as sag, swell, transients and unbalanced. Being light weighted and fast, the proposed technique can be integrated into smart grid devices such as smart meter in order to perform a real-time disturbance monitoring. The continuous monitoring of power quality in smart meters will give helpful insight for quality power transmission and management

Efficiency of Polyphenol Extraction from Artificial Honey Using C18 Cartridges and Amberlite„ XAD-2 Resin: A Comparative Study

A comparative study of the extraction efficiency of nine known polyphenols [phenolic acids (benzoic acid, dihydroxybenzoic acid, gallic acid, trans-cinnamic acid, and vanillic acid) and flavonoids (naringenin, naringin, quercetin, and rutin)] was conducted by deliberately adding the polyphenols to an artificial honey solution and performing solid phase extraction (SPE). Two SPE methods were compared: one using Amberlite XAD-2 resin and another one using a C18 cartridge. A gradient high performance liquid chromatography system with an RP18 column and photodiode array detector was utilized to analyze the extracted polyphenols. The mean percent of recovery from the C18 cartridges was 74.2%, while that from the Amberlite XAD-2 resin was 43.7%. The recoveries of vanillic acid, naringin, and rutin were excellent (>90%); however, gallic acid was not obtained when C18 cartridges were used. Additionally, the reusability of Amberlite XAD-2 resin was investigated, revealing that the mean recovery of polyphenols decreased from 43.7% (1st extraction) to 29.3% (3rd extraction). It was concluded that although Amberlite XAD-2 resin yielded a higher number of compounds, C18 cartridges gave a better extraction recovery. The lower recovery seen for the Amberlite XAD-2 resin also cannot be compensated by repeated extractions due to the gradual decrease of extraction recovery when reused

Reaching an Agreement for the Elimination of Child Labour from the Supply Chains

This article examines how child labour can be eliminated from various supply chains in Bangladesh. Reinforcing this issue is important to comply with international labour standards on child labour and to avoid potential trade sanctions of various types. Drawing upon the examples of other mechanisms to implement international labour standards particularly in a situation when domestic initiatives remain largely ineffective, it is argued that various local and international actors in the supply chains have a key role to play in actively enforcing this international standard to help support an economy free from the curse of child labour. This article proposes that an international legally binding agreement among global importers, unions, and local stakeholders to improve the child labour situation may provide the best mechanism to eliminate this problem from various supply chains in Bangladesh

PROLONGED HEATING OF HONEY INCREASES ITS ANTIOXIDANT POTENTIAL BUT DECREASES ITS ANTIMICROBIAL ACTIVITY

Background: Honey is renowned for its antioxidant, antimicrobial and medicinal properties. It is typically heated and filtered during processing to avoid crystallization. However, few studies have reported its heating effect and the antioxidant and antimicrobial activities of honey. Materials and Methods: In this study, honey samples were collected from eight different honey-producing sites in Bangladesh and heated to 50ºC, 70ºC and 90ºC for 12 hours, while the antioxidant potentials and antimicrobial properties of the heated samples were compared with those of the unheated samples. Antimicrobial properties were investigated against one Gram-positive and eight Gram-negative bacteria. Other physicochemical and biochemical properties were also determined. Results: Interestingly, there was a proportionate increase in the amount of antioxidant compounds (phenolics and flavonoids) as well as antioxidant potentials proportional with the amount of heat introduced, whereas the antimicrobial properties of the honey samples were reduced with increasing heat. Conclusion: In conclusion, though prolonged heat treatment of honey can increase its antioxidant potential, antimicrobial activities are compromised

Helicobacter pylori infection in diabetes mellitus patients with peptic ulcer disease

Background and objectives: Helicobacter pylori infection is suspected to be associated with extra-gastrointestinal disorders such as diabetes mellitus (DM). It is still a subject of investigation whether H. pylori has a pathogenic role on DM or diabetic patients have an increased susceptibility to H. pylori infection. The aim of the present study was to find out the rate of H. pylori infection in individuals with and without DM.&#x0D; Materials and methods: The study was conducted on 72 diabetic and 19 non-diabetic adult individuals with dyspeptic symptoms attending the BIRDEM General Hospital for diagnostic endoscopy. All cases were tested for H. pylori stool antigen by rapid immunochromatographic test (ICT), urease production in biopsy samples by rapid urease test (RUT), and serum anti-H. pylori IgA and anti-CagA IgG antibodies by enzyme-linked immunosorbent assay (ELISA). Any case that had peptic ulcer/erosion and was positive for H. pylori stool antigen or rapid urease test (RUT) was defined as H. pylori positive case.&#x0D; Results: There was no significant (p=0.095) difference in H. pylori infection between diabetics and non-diabetics (68.1% vs 47.4%). Presence of ulcer and erosion were not significantly different among diabetics and non-diabetics. Anti-H. pylori IgA positivity rate in H. pylori positive diabetic and non-diabetic cases were 65.3% and 55.6% (p=0.575) respectively while anti-CagA IgG rate in those cases were 46.9% and 66.7% (p=0.276) respectively.&#x0D; Conclusion: The present study did not reveal any significant difference in H. pylori infection between individuals with and without DM having peptic ulcer/erosion.&#x0D; Ibrahim Med. Coll. J. 2020; 14(2): 27-32</jats:p

Diaphragm ultrasound as a better predictor of successful extubation from mechanical ventilation than rapid shallow breathing index

Background In 3%–19% of patients, reintubation is needed 48–72 hours following extubation, which increases intensive care unit (ICU) morbidity, mortality, and expenses. Extubation failure is frequently caused by diaphragm dysfunction. Ultrasonography can be used to determine the mobility and thickness of the diaphragm. This study looked at the role of diaphragm excursion (DE) and thickening fraction in predicting successful extubation from mechanical ventilation. Methods Thirty-one patients were extubated with the advice of an ICU consultant using the ICU weaning regimen and diaphragm ultrasonography was performed. Ultrasound DE and thickening fraction were measured three times: at the commencement of the T-piece experiment, at 10 minutes, and immediately before extubation. All patients' parameters were monitored for 48 hours after extubation. Rapid shallow breathing index (RSBI) was also measured at the same time. Results Successful extubation was significantly correlated with DE (P<0.001). Receiver curve analysis for DE to predict successful extubation revealed good properties (area under the curve [AUC], 0.83; P<0.001); sensitivity, 77.8%; specificity, 84.6%; positive predictive value (PPV), 84.6 %; negative predictive value (NPV), 73.3% while cut-off value, 11.43 mm. Diaphragm thickening fraction (DTF) also revealed moderate curve properties (AUC, 0.69; P=0.06); sensitivity, 61.1%; specificity, 84.6%; PPV, 87.5%; NPV, 61.1% with cut-off value 22.33% although former one was slightly better. RSBI could not reach good receiver operating characteristic value at cut-off points 100 breaths/min/L (AUC, 0.58; P=0.47); sensitivity, 66.7%; specificity, 53.8%; PPV, 66.7%; NPV, 53.8%). Conclusions To decrease the rate of reintubation, DE and DTF are better indicators of successful extubation. DE outperforms DTF