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Introduction: Acute pancreatitis with unknown etiology comprises about 10-30% of all cases of acute pancreatitis. Endoscopic ultrasound is an important tool for revealing etiologies of the unknown causes of acute pancreatitis. The aim of this study was to evaluate the role of endoscopic ultrasound in sorting out the cause of idiopathic acute pancreatitis. Materials & Methods: It was a cross-sectional study which was carried out in the department of gastroenterology of Sir Salimullah medical college & Mitford hospital from January 2013 to December 2017. A total of 109 patients suffering from acute idiopathic pancreatitis were enrolled in this study. Underlying etiologies could not be detected after thorough history, physical examinations, blood tests, ultrasonography, CT, and/or MRI. These patients underwent endoscopic ultrasound under proper sedation after taking informed consent. Results: Among the 109 patients, 67 were male and 42 were female (P=0.03). Number of patients below 40yrs of age were 67 and above 40 years of age were 42 (P=0.01). Moreover, 81 patients had their gall bladder in situ and 28 had previous history of cholecystectomy (P=0.001). Microlithiasis 20 (24.6%), common bile duct stone or sludge 20 (24.6%), ampullary neoplasm 20 (24.67%), early stage of chronic pancreatitis 12 (14.8%), biliary ascariasis 08 (9.8%), small pancreatic head tumor 02 (2.5%) and pancreatic divisum 02 (2.5%) were found out as the underlying etiologies of idiopathic acute pancreatitis patients who had intact gall bladder. In patients who underwent cholecystectomy; endoscopic ultrasound revealed chronic pancreatitis 04 (14.3%), common bile duct stone or sludge 20 (24.6%), biliary ascariasis 06 (21.4%) and ampullary neoplasm 01 (3.5%) as the hidden causes of idiopathic acute pancreatitis. Conclusion: Gastroenterologists face difficulties to diagnose the actual etiology of idiopathic acute pancreatitis. As endoscopic ultrasound shows high efficacy and accuracy to detect etiologies in such cases; it can be included as a first line investigation in idiopathic acute pancreatitis.

A high gain optically transparent microstrip patch antenna for K band (18 GHz–27 GHz) satellite communication has been proposed and investigated in this paper. In order to make sure the property of optical transparency of the antenna, optically transparent materials have been chosen for all the layers of the microstrip patch antenna. Indium Tin Oxide (ITO) film is opted for the radiating patch and ground plane where the substrate is made of pyrex glass (lossy) (Ɛ r = 4.82 and tanδ = 0.0054). The proposed transparent antenna operates at center frequency of 24.8 GHz ranging from 17.625 GHz to 30.523 GHz that covers the entire K band of satellite communication. The transparency property of the patch antenna is useful to minimize the shadowing effect of the solar antenna as well as helpful to guarantee the maximum uses of satellite surface area. The proposed antenna has high IEEE gain of 12.36 dB and directivity of 13.38 dBi including efficiency of 92.38%. It also possesses very wide bandwidth (12.898 GHz), high front to back ratio (16.699 dB) and very good VSWR (1.0566) at center operating frequency.

A wideband inset feed microstrip Yagi-Uda array antenna on photonic crystal substrate with high gain and front to back (F/B) ratio for 5 GHz Wi-Fi band has been proposed. At first, a microstrip Yagi-Uda array antenna has been designed on Rogers RT/Duroid 5880 (lossy) having dielectric constant of 2.2 and tangent loss of 0.0009. Later on, few numbers of cylindrical air gaps has been introduced in the substrate and the length and width of patch somewhat has been readjusted without changing overall size of the antenna. In that case the performance of the antenna is enhanced in terms of IEEE gain (9.816 dB), directivity (10.15 dBi), bandwidth (396.2 MHz), efficiency (96.71%) and F/B ratio (29.094 dB) though return loss somewhat decreases. So the proposed antenna possesses very high front to back ratio as well as high gain and wide bandwidth. A vivid comparison between the microstrip Yagi-Uda array antennas without air gaps and with air gaps have also been presented in this paper.

All conventional energy resources are withering day by day. Ergo we have to shift from conventional to non-conventional energy resources. In this paper the combination of conventional and non-conventional energy resources takes place. We can give uninterrupted power by using hybrid energy system. Basically this system involves the integration of two energy system that will give continuous power. Solar panels are used for converting solar energy and diesel generator are used for producing electricity. Optimization of hybrid renewable energy systems looks into the process of selecting the best components and its sizing with appropriate operation strategy to provide cheap, efficient, reliable and cost effective alternative energy using HOMER. The optimization results of hybrid energy system consists of solar photovoltaic system with battery, inverter and generator and has the lowest total net present cost (NPC) at $323568 and cost of electricity (COE) of $0.384per Kwh.

In electronic communications, the radio frequency spectrum (RF Signal) is widely used in all the modern communication systems. The generation and transmission of RF signal can be accomplished by various modulation techniques. Frequency modulation is such a technique. The communication through cordless & Cell phones, radio and TV broadcast stations, satellite communication systems, Bluetooth module and Wi-Fi is now becoming an essential part of human life. All these systems use RF spectrums for communication. The sound coming out from the modern communicating devices is Frequency Modulated (FM) signals. For noise free communications, frequency modulation is used by all the modern speech communicating devices. The device that is discussed in the paper is a low power, narrowband frequency modulated transmitter which can transmit sound or speech signals around 100 meters with only a 10 cm copper wire as an antenna. The sound quality is very clear and noise free. As, the VHF RF FM transmitter is designed with crystal oscillator, so frequency is fixed at 88.7 MHz. No parasitic effect results in the circuit for the contribution of the crystal.

A design and performance analysis of a metamaterial (MTM) based rectangular microstrip patch antenna (RMPA) with four dual isosceles triangular defects on the metallic ground plane have been presented in this paper. At first, a conventional RMPA is designed by using Isola FR-408 (lossy) substrate material (e r = 3.75 and tan δ = 0.0013). After that, the RMPA with four dual isosceles triangular defected ground structure (DGS) has been designed and verified as metamaterial with the help of Nicolson Ross Weir (NRW) method. Professional CST software has been used to perform the simulation of the designed antennas. The bandwidth of the proposed metamaterial antenna is enhanced by 345.71% compared to our designed conventional RMPA (105 MHz for conventional RMPA and 468 MHz for metamaterial RMPA), return loss is reduced from −23.10 dB to −44.299 dB, gain is enhanced from 0.205 dB to 6.291 dB, directivity is increased from 5.179 dB to 9.314 dB and voltage standing wave ratio (VSWR) is of 1.0123 which indicates very good VSWR.

Article 31 of the Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPs) was amended for the first time and a new Article (31bis) was introduced by inserting Article 31bis after Article 31 as a solution to a problem arising from Paragraph 6 of Doha Declaration which was related to the Public Health and TRIPs. Article 31(f) of the previous TRIPs text deals with the patented invention without the authorization of the patentee under Compulsory Licensing by the member country which clearly states “(f) any such use shall be authorized predominantly for the supply of the domestic market of the Member authorizing such use, which creates challenges for developing countries, especially for the Least Developed Countries which have minimum or no manufacturing capacity. In this context, this paper seeks to analyze some issues and considerations that have been elucidated through answering four key questions: Q1. What constitutes ‘effective use’ of compulsory licensing? Q2. What ‘difficulties’ did the affected countries face? Q3. Does the amendment to TRIPS overcome these difficulties? Q4. How can it be made to enable more effective use of compulsory licensing either (a) through revision or (b) through its practical implementation. In addition, the coverage and scope of the term ‘effective use’ have been identified in this paper. Finally, difficulties faced by developing countries in ensuring ‘effective use’ of compulsory licensing have also been discussed.

Aims: Rural Development Scheme (RDS) under Islami Bank Bangladesh Limited (IBBL) is an innovative typology of microfinance, envisaged to answer the need of rural poor. This study was planned to reveal the socioeconomic impact of RDS microfinance on the women beneficiaries in a selected district of Bangladesh. Place and Duration of the Study: This study was conducted in the district of Barisal. Data were collected from July to August, 2014. Methodology: This study was mainly based on primary information, however the secondary information was also collected to compare the before and after situation of loan withdrawal. To achieve study objectives data was collected from 206 randomly selected, RDS beneficiary women who engaged with the program for at least one year. Descriptive statistics such as mean, median, mode, standard deviation, etc., were used to describe the selected characteristics of the Original Research Article Jahan and Rashid; AJAEES, 6(3): 136-148, 2015; Article no.AJAEES.2015.071 137 respondents. Z-statistics was employed to compare the before and after situation of loan withdrawal. This study also used OLS regression to see the contribution of selected factor on the improvement of women beneficiaries. Results: The values Z statistics confirmed that highest change was taken place in social capital development followed by yearly income from non-agricultural sources, ownership of sanitary toilet, and ownership of tube-well. In case of social capital highest improvement was found in participation in family-decision making followed by self confidence, and consciousness about self-economic development. OLS regression confirmed that among the eight selected variables three variables, namely the number of earning members per family, the total amount of loan received, and yearly expenditure together can explain 46.5% variation in income growth. Conclusion: This study analyzed both monetary and social impacts of RDS microfinance and arrived at a general conclusion that this program grossly has a remarkable impact on selected socioeconomic aspects of the women clients.

This work demonstrates the impact of human body on an 800 MHz inset fed rectangular microstrip patch antenna characteristics. The antenna was simulated over a human phantom model consisting human thigh muscle using CST Microwave Studio. The distance between the antenna and human thigh muscle was varied to analyze the changes in antenna performance for waveguide port feeding. The results exhibited significant changes in antenna characteristics, especially the shifting of center frequency to a lower value due to the human body. Specific Absorption Rate (SAR) was studied as well to illustrate how on-body communication or mobile phone antennas of GSM band might affect human body when mobile phones are kept in pants pocket.

Purpose: Globally, many extension professionals and policy-makers are advocating fee based services, in addressing the fund shortage and sustainable provision of agricultural advisory services. Hence, the article attempts to expose the farmers' willingness to pay (WTP) as agricultural extension in Bangladesh is experiencing chronic fund crisis.Methodology: This study used contingent valuation method (CVM) for investigating farmers' WTP. Logit and Tobit model was employed to assess the determinants of WTP and amount willing to pay (AWTP) respectively. Besides, different qualitative methods were employed to have a deeper understanding of the research problems.Findings: WTP was conditioned by providing quality extension services at farm and/or home of the farmers. The study also focused on farmers preferred mode of payment, criteria influencing payment decisions and the type of services for which they are willing to pay. Paid model can contribute to quality extension services, if started with a marke...

Exposure of the general public to low-level RF fields causes direct or indirect coupling of the fields in the human body. Due to this coupling, there is an induction of the fields inside the body tissue that causes currents in the tissue while the tissue absorbs RF power. In this work, the RF absorption by a biological tissue was measured by using an antenna trainer in a laboratory set up by varying distances and angles of RF radiation source. Using the detector current, the absorbed power by the tissue as well as the incident component of Electric field upon the receiving antenna was calculated with and without the tissue. From calculating rms value of the field, the voltage inside the tissue was estimated. Using the absorbed power and voltage inside the tissue, the impedance inside the tissue was calculated. Results indicated that the more impedance values inside the tissue incur more absorption of RF power. The more dominant effects for angles than the distances were obtained for absorbed power by the tissue.

In this work, the impact of human heart on an 800 MHz inset fed rectangular microstrip patch antenna characteristics were investigated using CST Microwave Studio. The antenna was simulated over a mimic human heart muscle and the distance between them was varied to analyze the changes in Specific Absorption Rate (SAR) upon antenna performance parameters (specifically, directivity & surface current) for discreet and waveguide port feeding. The results exhibited that the center frequency of the antenna was shifted to lower value and an increase in SAR values when the antenna was closer to heart for both the feeding techniques. However, the discrete port had more values of SAR than the waveguide port but for both cases SAR decreased with the increment of antenna distance from heart. SAR values for up to 4 mm distance in between the antenna and human heart did not satisfy IEEE and ICNIRP standards. For increasing surface current, the SAR values decreases due to less penetration of flux inside the tissue for both feeding techniques. Increasing directivity resulted decrement of SAR values due to the fact that more reflection of the wave from the tissue happened for more directivity. This work demonstrates how mobile phone antennas of GSM band affect human heart and how human heart affects antenna resonance frequency when mobile phones are kept in chest pocket.

Background: One of the main goals of RNA-seq data analysis is identification of biomarkers that are differentially expressed (DE) across two or more experimental conditions. RNA-seq uses next generation sequencing technology and it has many advantages over microarrays. Numerous statistical methods have already been developed for identification the biomarkers from RNA-seq data. Most of these methods were based on either Poisson distribution or negative binomial distribution. However, efficient biomarker identification from discrete RNA-seq data is hampered by existing methods when the datasets contain outliers or extreme observations. Specially, the performance of these methods becomes more severe when the data come from a small number of samples in the presence of outliers. Therefore, in this study, an attempt is made to propose an outlier detection and modification approach for RNA-seq data to overcome the aforesaid problems of traditional methods. We make our proposed method facilitate in RNA-seq data by transforming the read count data into continuous data. Methods: We use median control chart to detect and modify the outlying observation in a log-transformed RNA-seq dataset. To investigate the performance of the proposed method in absence and presence of outliers, we employ the five popular biomarker selection methods (edgeR, edgeR_robust, DEseq, DEseq2 and limma) both in simulated and real datasets. Results: The simulation results strongly suggest that the performance of the proposed method improved in the presence of outliers. The proposed method also detected an additional 18 outlying DE genes from a real mouse RNA-seq dataset that were not detected by traditional methods. Using the KEGG pathway and gene ontology analysis results we reveal that these genes may be biomarkers, which require validation in a wet lab. Conclusions: Our proposal is to apply the proposed method for biomarker identification from other RNA-seq data.

Vertically stacked pruned optical banyan networks with extra planes (in short, EP-VSOB networks) have lower switch count and optimal time complexity (O(log2 N)) for routing N input requests. However, blocking probability is relatively higher than that of a VSOB networks using regular banyan planes. In the EP-VSOB architecture, the number of pruned planes has always been considered as N , and a few extra planes (regular banyan) have been added with these pruned planes. In this paper we present the results of blocking analysis of a more generalized architecture in which the number of pruned planes can be 2x, where x ⩾ 0 in addition to the variable extra planes. This generalization helps us make a compromise between different constraints and performance metrics. Our simulation results show that for some given performance requirements (e.g. cost, speed or blocking probability) we can choose a network that has lower switch count compared to N -plane pruned crosstalk-free optical banyan networks. For example, to ensure blocking probability

In this paper, 15 different shaped (E, F, inverted F, G, H, I, L, inverted L, S, T, inverted T, U, inverted U, W and inverted W) conventional microstrip patch antennas along with a dumbbell (H) shaped Defected Ground Structure (DGS) in each are designed and simulated at 2.4 GHz operating frequency using CST Microwave Studio Suite. The efficiency of microstrip patch antennas are compared in terms of surface wave concept and the antenna with H shaped patch exhibiting total efficiency of −2.546 dB is found most efficient. The implementation of this work is highly anticipated to be employed for designing hybrid shaped patches for WLAN, wireless network (Wi-Fi and Bluetooth), nonstandard RF remote, ISM band applications.

In this paper, we address the issue of faster connection establishment in a large vertically stacked optical Banyan (VSOB) network. The best known global routing algorithm, which turns an N × N crosstalk-free VSOB network into a rearrangeably non-blocking one, has time complexity O ( N log N ). This is quite large compared to O ( N log N ) time complexity of a single plane banyan network, which is a self-routing network with very high blocking probability. For a large size of switching network this O ( N log N ) time complexity may result unacceptably long delay. Therefore, an optical network with very low blocking probability and O ( N log N ) time complexity will be useful. Previously proposed Plane Fixed Routing (PFR) algorithm has O (log N ) time complexity but results in higher than 2% blocking probability with zero-crosstalk constraint for a network as large as 4096 × 4096 at full load. In this paper, first we propose the pruning of VSOB networks that reduces the hardware cost by almost 30%. The networks can still use the PFR algorithm and results in the same blocking probability. However, we show that the blocking probability can be reduced dramatically while keeping the optimum time complexity O (log N ) by allowing only a small amount of crosstalk. Then, we propose a new kind of switching networks in which extra regular banyan planes have been added with the pruned VBOS (P-VSOB) networks. Necessary routing algorithms, namely, PFR_RS and PFR_LS show that this new switching network can reduce the blocking probability to very low value even with zero-crosstalk constraint while keeping the hardware cost 3almost the same as for P-VSOB networks. Both these algorithms also have time complexity O ( N log N ).

Vertical stacking of multiple optical banyan networks is a novel scheme for building banyan-based nonblocking optical switches. The resulting network, namely vertically stacked optical banyan (VSOB) network, preserves the properties of small depth and absolutely loss uniformity but loses the nice self-routing capability of banyan networks. To guarantee a high switching speed, routing in VSOB network needs special attentions so that paths can be established as fast as possible. The best known global routing algorithm for an N × N nonblocking VSOB network has the time complexity of O(Nlog N), which will introduce an unacceptable long delay in path establishment for a large size optical switch. In this paper, we propose two fast routing algorithms for the VSOB network based on the idea of inputs grouping. The two algorithms, namely plane fixed routing (PFR) algorithm and partially random routing (PRR) algorithm, have the time complexities of O(log N) and O$(\sqrt{N})$ respectively, and FR algorithm can actually turn a VSOB network into a self-routing one. Extensive simulation based on a network simulator indicates that for large VSOB networks our new algorithms can achieve a reasonably low blocking probability while guarantee a very high switching speed.

Banyan networks are attractive for constructing directional coupler (DC)-based optical switching networks for their small depth and self-routing capability. Crosstalk between optical signals passing through the same DC is an intrinsic drawback in DC-based optical networks. Vertical stacking of multiple copies of an optical banyan network is a novel scheme for building nonblocking (crosstalk-free) optical switching networks. The resulting network, namely vertically stacked optical banyan (VSOB) network, preserves all the properties of the banyan network, but increases the hardware cost significantly. Though much work has been done for determining the minimum number of stacked copies (planes) required for a nonblocking VSOB network, little is known on analyzing the blocking probabilities of VSOB networks that do not meet the nonblocking condition (i.e., with fewer stacked copies than required by the nonblocking condition). In this paper, we analyze the blocking probabilities of VSOB networks and develop their upper and lower bounds with respect to the number of planes in the networks. These bounds depict accurately the overall blocking behaviors of VSOB networks and agree with the conditions of strictly nonblocking and rearrangeably nonblocking VSOB networks respectively. Extensive simulation on a network simulator with both random routing and packing strategy has shown that the blocking probabilities of both strategies fall nicely within our bounds, and the blocking probability of packing strategy actually matches the lower bound. The proposed bounds are significant because they reveal the inherent relationships between blocking probability and network hardware cost in terms of the number of planes, and provide network developers a quantitative guidance to trade blocking probability for hardware cost. In particular, our bounds provide network designers an effective tool to estimate the minimum and maximum blocking probabilities of VSOB networks in which different routing strategies may be applied. An interesting conclusion drawn from our work that has practical applications is that the hardware cost of a VSOB network can be reduced dramatically if a predictable and almost negligible nonzero blocking probability is allowed.

Vertical stacking is a novel alternative for constructing nonblocking multistage interconnection networks (MINs). Rearrangeably nonblocking optical MINs are attractive since they have lower complexity than their strictly nonblocking counterparts. In this paper, we study the realization of crosstalk-free permutations in rearrangeably nonblocking, self-routing banyan-type optical MINs built on vertical stacking. An available scheme for realizing crosstalk-free permutation in this type of optical MINs requires to first decompose a permutation into multiple crosstalk-free partial permutations based on the Euler-Split technique, and then to realize them crosstalk-free in different planes (stacked copies) of the MIN simultaneously. The overall time complexity of this scheme to realize a crosstalk-free permutation in an N × N optical MIN is O(N log N) which is dominated by the complexity of crosstalk-free decomposition. In this paper, we propose a new scheme for realizing permutations in this class of vertically stacked optical MINs crosstalk-free. The basic idea of the new scheme is to classify permutations into permutation classes such that all permutations in one class share the same crosstalk-free decomposition pattern. By running the Euler-Split based crosstalk-free decomposition only once for a permutation class and applying the obtained crosstalk-free decomposition pattern to all permutations in the class, crosstalk-free decomposition of permutations can be realized in a more efficient way. We show that the number of permutations in a permutation class is huge (√N!)√N when log2N is even and (√2N!)√N/2 when log2N is odd), and thus the average time complexity of crosstalk-free decomposition of a permutation becomes O(N).

With the current technology, all-optical networks require nonblocking switch architectures for building optical cross-connects. The crossbar switch has been widely used for building an optical cross-connect due to its simple routing algorithm and short path setup time. It is known that the crossbar suffers from huge signal loss and crosstalk. The Clos network uses a crossbar as building block and reduces switch complexity, but it does not significantly reduce signal loss and crosstalk. Although the Spanke's network eliminates the crosstalk problem, it increases the number of switching elements required considerably (to 2N 2 - 2N). In this paper, we propose a new architecture for building nonblocking optical switching networks that has much lower signal loss and crosstalk than the crossbar without increasing switch complexity. Using this architecture we can build non-squared nonblocking networks that can be used as building block for the Clos network. The resulting Clos network will then have not only lower signal loss and crosstalk but also a lower switch complexity.

During the path establishment, states of switching elements in the switch network may need rearrangement. C.-T. Lea et. al [1] has first mentioned about the rearrangement behavior of the switching networks. He has analyzed the frequency of its occurrence using stochastic method. It is notable that rearrangement behavior of switching network includes rearrangement of connections and rearrangement of switching elements. Optimization of rearrangement cost of switching network can save both power and time, which in turn can increase the switching speed. This paper determines the rearrangement cost of strictly non-blocking Vertically Stacked Optical Banyan networks in terms of switching elements. We believe that our result will be helpful in designing, implementing and analyzing different algorithms of the networks.

In this Paper, we have derived the numerical integration formula for unequal data spacing. For doing so we use Newton’s Divided difference formula to evaluate general quadrature formula and then generate Trapezoidal and Simpson’s rules for the unequal data spacing with error terms. Finally we use numerical examples to compare the numerical results with analytical results and the well-known Monte- Carlo integration results and find excellent agreement.

Due to its nice properties of small depth and absolute signal loss uniformity, vertical stacking of optical banyan (VSOB) networks becomes an attractive optical switch architecture. It is expected that a VSOB switch will have a good fault-tolerant capability, because it consists of multiple banyan networks. To verify our expectation, in this paper we study the overall blocking behavior of a VSOB switch by establishing an upper bound on its blocking probability in presence of link failures. The upper bound accurately depicts the overall blocking behavior of a VSOB switch for a reasonable small link failure rate, as verified by extensive simulation results. Although our upper bound demonstrates that VSOB switches have a good fault-tolerance property, it reveals a surprising overall blocking behavior of a faulty VSOB switch that, not as we usually expected, the blocking probability of the switch may not always increase monotonously with the increase of link failure rate. Our upper bound is significant, because it provides switch designers a quantitative tool to determine the effects of link failure on the blocking behavior and to estimate the maximum blocking probability of a VSOB switch, in which different routing algorithms can be applied with a guaranteed performance in terms of blocking probability and hardware cost.

Vertical stacking is a novel scheme in creating nonblocking multistage interconnection networks (MINs). Available results indicate that under the crosstalk-free constraint, the hardware cost is high for a strictly nonblocking optical MIN based on the scheme. Packing strategy is a commonly used routing strategy for reducing network hardware. In this paper, we look into the nonblocking conditions for crosstalk-free optical MINs under packing strategy. It is shown that packing strategy is very efficient in reducing the hardware cost of a nonblocking optical MIN under the crosstalk-free constraint. The results in the paper will be useful in designing optical MINs.