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Tropical cyclones of the Bay of Bengal (BoB) that formed near the synoptic-scale dryline usually intensified over a short distance (~600-800 km) within 3 days and caused severe destruction after landfall. High-resolution simulations of very severe cyclonic storms in association with dryline indicate that the meridional shear aids in the development of a group of linear convective cells that mature as an east-west oriented quasi-linear convective system (QLCS) within the boundary between the dry-moist air masses. The leading edge deep convections are supported by low-level moist southwesterly inflow; however, the typical mid-level mesoscale convective vortex (MCV) associated with these QLCS is unremarkable due to a very narrow trailing stratiform region within the QLCS. Supercells are likely to be organized within the QLCS due to extremely unstable atmospheric conditions resulting from a strong vertical shear of 27-39 m s−1 between 0-6 km and large convective available potential energy of >3000 J kg−1. The vertical shear veering with height causes several numbers of low-level mesovortices having diameters less than 10 km at the leading edge in the different convective stages of the QLCS. The dryline aloft in the BoB produces horizontal positive shear vorticity of the order 10–5 s−1 with higher values in the levels 850-600 hPa. The advection of intense cloud-scale cyclonic vortices (~10–3 s−1) assists and enhances a cyclonic vortex to the rear side of the QLCS that performs as an MCV for cyclogenesis over the BoB.

There is a paucity of data on the incidence, risk factors, and treatment of splanchnic vein thrombosis (SVT) in acute pancreatitis (AP).All AP admissions between 2018 and 2021 across North East of England were included. Anticoagulation was considered in the presence of superior mesenteric vein/portal vein (SMV/PV) thrombus or progressive splenic vein thrombus (SpVT). The impact of such a selective anticoagulation policy, on vein recanalisation rates and bleeding complications were explored.401 patients (median age 58) were admitted with AP. 109 patients (27.2%) developed SVT. The splenic vein in isolation was the most common site (n = 46) followed by SMV/PV (n = 36) and combined SMV/PV and SpVT (n = 27). On multivariate logistic regression alcohol aetiology (OR 2.64, 95% CI [1.43-5.01]) and50% necrosis of the pancreas (OR 14.6, 95% CI [1.43-383.9]) increased the risk of developing SVT. The rate of recanalization with anticoagulation was higher for PVT (66.7%; 42/63) than in SpVT (2/11; p = 0.003). 5/74 of anticoagulated patients developed bleeding complications while 0/35 patients not anticoagulated had bleeding complications (p = 0.4).The risk of SVT increases with AP severity and with extent of pancreatic necrosis. A selective anticoagulation policy for PVT and progressive SpVT in AP is associated with favourable outcomes with no increased risk of bleeding complications.

Background There is paucity of data on the incidence, risk factors and role of anticoagulation for splanchnic vein thrombosis (SVT) in acute pancreatitis (AP). Methods A retrospective review of AP admissions between 2018-2021 across North East England was undertaken. Data on demographics, etiology, severity of AP and SVT was collected. In addition, a selective anticoagulation policy for portal vein thrombosis (PVT) and progressive splenic vein thrombosis was explored. Results 401 patients were included with a mean age of 57.0 and M:F ratio of 1.6:1. 152 patients developed intestinal oedematous pancreatitis and 249 developed necrotising pancreatitis based on Revised Atlanta criteria (RAC). 109 patients (27.2%) developed SVT of which 27 developed a PVT and splenic vein thrombus, 36 PVT only and 46 splenic vein thrombus only. On univariate analysis, alcoholic aetiology, severe pancreatitis, necrotising pancreatitis with >50% necrosis and elevated CRP at 2 weeks were risk factors for developing SVT. On multivariable analysis, alcohol aetiology (OR 2.6, p = 0.002), and >50% pancreatic necrosis (OR 14.6,p = 0.048) increased the risk of developing SVT . 58 patients received anticoagulation for SVT, with a median duration of 90 days of anticoagulation. Recanalization rates were higher for PVT when compared to splenic vein thrombosis. 6 patients developing bleeding complications whilst on anticoagulation therapy. Conclusions A third of patients with AP develop SVT, particularly those with severe AP secondary to alcohol and with extensive pancreatic necrosis. A selective anticoagulation policy was associated with improved recanalization rates and fewer bleeding complications.

Background This systematic review explored the efficacy of different pain relief modalities used in the management of postoperative pain following pancreatoduodenectomy (PD) and distal pancreatectomy (DP) and impact on perioperative outcomes. Methods MEDLINE (OVID), Embase, Pubmed, Web of Science and CENTRAL databases were searched using PRISMA framework. Primary outcomes included pain on postoperative day 2 and 4 and respiratory morbidity. Secondary outcomes included operation time, bile leak, delayed gastric emptying, postoperative pancreatic fistula, length of stay, and opioid use. Results Five randomized controlled trials and seven retrospective cohort studies (1313 patients) were included in the systematic review. Studies compared epidural analgesia (EDA) (n = 845), patient controlled analgesia (PCA) (n = 425) and transabdominal wound catheters (TAWC) (n = 43). EDA versus PCA following PD was compared in eight studies (1004 patients) in the quantitative meta-analysis. Pain scores on day 2 (p = 0.19) and 4 (p = 0.18) and respiratory morbidity (p = 0.42) were comparable between EDA and PCA. Operative times, bile leak, delayed gastric emptying, pancreatic fistula, opioid use, and length of stay also were comparable between EDA and PCA. Pain scores and perioperative outcomes were comparable between EDA and PCA following DP and EDA and TAWC following PD. Conclusions EDA, PCA and TAWC are the most frequently used analgesic modalities in pancreatic surgery. Pain relief and other perioperative outcomes are comparable between them. Further larger randomized controlled trials are warranted to explore the relative merits of each analgesic modality on postoperative outcomes with emphasis on postoperative complications.

Aim: The present study was designed to investigate the antidiabetic & hypolipidemic activity of Calotropis gigantean (Family: Apocynaceae) in alloxan-induced diabetic rat model. Study Design: In vivo study was carried out by ethanolic leaf extract was administered in 250 mg/kg body weight concentration and then subjected to different rats models to authenticate the antidiabetic and hyperlipidimic properties of the plant. Place and Duration of Study: Department of Pharmacy, Southeast University, Banani, Dhaka-1213,Bangladesh within a period of July 2018 to December, 2018. Methodology: Diabetes was induced in rats by an intraperitoneal injection (i.p) of alloxan (100 mg/kg B.W). Ethanolic leaf extract of C. gigantean (250 mg/kg B.W) was administrated orally as a single dose per day to the diabetic rats for 7 days. The negative control group received 0.5 ml of sterile normal saline water orally & positive control group received metformin orally. Synergistic effect of plant was evaluated by combination with 100 mg/kg B.W & 50 mg/kg B.W oral administration of metformin. After 7 days study period, fasting blood glucose, total cholesterol, triglyceride, high-density lipoprotein cholesterol, liver weight & body weight were measured only for diabetic group to observe the effects of diabetes induction. Results: Individual plant extract (250 mg/Kg B.W) & Metformin (100 mg/kg B.W) reduced FBG significantly by 52% (P

The risk factors for surgical site infection (SSI) after HPB surgery are poorly defined. This meta-analysis aimed to quantify the SSI rates and risk factors for SSI after pancreas and liver resection. The PUBMED, MEDLINE and EMBASE databases were systematically searched using the PRISMA framework. The primary outcome measure was pooled SSI rates. The secondary outcome measure was risk factor profile determination for SSI. The overall rate of SSI after pancreatic and liver resection was 25.1 and 10.4%, respectively (p

A northeast- to southwest-oriented surface dryline with a dew point gradient of 1 °C per 10 km develops along the eastern Indian coast during the entire premonsoon season. Deep, hot, dry air of up to 500 hPa moves from arid regions in Southwest Asia and Western India to the Bay of Bengal (BoB), and warm, shallow, moist air from the BoB penetrates below the dry air, forming an inclined moisture gradient aloft to the east and reaching the surface to the west. The slope of the gradient depends on the vertically increased southwesterly wind over the BoB, which gradually intensifies from March to May. Diurnal low-level temperature variations over the land cause periodic movements of the dry-moist air convergence zone at the surface in the zonal direction. During the premonsoon, the average east–west diurnal oscillation of the surface dryline is approximately 100 km, and the eastward movement is almost three times faster than the westward movement.

Mesoscale convective systems (MCSs) are an essential component of cyclogenesis, and their structure and characteristics determine the intensity and severity of associated cyclones. Case studies were performed by simulating tropical cyclones that formed during the pre- and postmonsoon periods in 2007 and 2010 over the Bay of Bengal (BoB). The pre- (post) monsoon environment was characterized by the coupling of northwesterly (southwesterly) wind to the early advance southwesterly (northeasterly) monsoonal wind in the BoB. The surges of low-level warm southwesterlies with clockwise-rotating vertical shear in the premonsoon period and moderately cool northeasterlies with anticlockwise-rotating vertical shear in the postmonsoon period transported moisture and triggered MCSs within preexisting disturbances near the monsoon trough over the BoB. Mature MCSs associated with bimodal cyclone formations were quasi linear, and they featured leading-edge deep convection and a trailing stratiform precipitation region, which was very narrow in the postmonsoon cases. In the premonsoon cases, the MCSs became severe bow echoes when intense and moist southwesterlies were imposed along the dryline convergence zone in the northern and northwestern BoB. However, the development formed a nonsevere and nonorganized linear system when the convergence zone was farther south of the dryline. In the postmonsoon cases, cyclogenesis was favored by squall-line MCSs with a north–south orientation over the BoB. All convective systems moved quickly, persisted for a long time, and contained suitable environments for developing low-level cyclonic mesovortices at their leading edges, which played an additional role in forming mesoscale convective vortices during cyclogenesis in the BoB.

The cyclone frequency distribution over the Bay of Bengal during 1990–2009 was distinctly bimodal, with a primary post-monsoon peak and a secondary pre-monsoon peak, despite the very high convective available potential energy (CAPE) during the pre-monsoon. The location of the monsoon trough over the bay is a primary factor in tropical cyclogenesis. Because the trough was in the northernmost bay during the pre-monsoon season, cyclogenesis was inactive in the southern bay, where a strong southwesterly wind shear was found. In this season, moreover, a hot, dry air mass extending vertically from 950 to 600 hPa was advected from northwestern India toward the bay. Moist, warm southwesterly winds penetrating below the deep, dry air mass caused a prominent dryline to form aloft on the northwestern side of the bay. The synoptic-scale hot, dry air forcing to the bay suppressed the active convection necessary for cyclogenesis. The strength of the stable environmental layer, represented by convective inhibition (CIN), was extremely large, and acted as a cap over the northern and northwestern bay. Conversely, during the post-monsoon, there were no horizontal temperature or moisture gradients, and CAPE and CIN were fairly modest. The entire bay was covered by a very deep, moist layer from the surface to 700 hPa transported from the east. The monsoon trough position and the environmental CIN in combination can explain the lower frequency of cyclogenesis during the pre-monsoon compared with the post-monsoon season.

Cyclone Sidr, one of the most devastating tropical cyclones that resulted in several thousand deaths and substantial damages, developed in the north Indian Ocean and made landfall over the Bangladesh coast on 15 November 2007. Observation and simulation results show that Sidr was embedded in a nonuniform environment and contained an intense outer rainband to the east of its center and a significant frontal band to the northwest. A detailed study of the outer rainband is performed by numerical simulation. The eastern band was a long, quasi-straight shape in the meridional direction that remained stationary relative to the cyclone center. This band was composed of convective cells that developed southeast of the center within a synoptic-scale convergence zone and propagated along the band toward the northeast quadrant. The speed of the downwind-propagating cells was greater than that of the cyclone, which resulted in a convective cluster northeast of the center. Only the downwind portion of the band consisted of convection with stratiform rain, whereas the upwind and middle portions contained active convective cells without stratiform rain. The band was located between the synoptic-scale flows of a weakly sheared, gradient-balanced westerly and a strongly sheared, nongradient-balanced prevailing southerly caused by the complex terrain of the Bay of Bengal’s southeast region. Low-level convergence along the band was dominated by cross-band flow from both sides of the band and was confined below 3 km. As the cyclone moved northward, the convergence zone resulted in the extension of band length up to ~800 km. The southerly at the eastern side of the center gradually accelerated and was directed toward the center by a strong pressure gradient force. The flow accumulated a substantial amount of water vapor from the sea in addition to the increased moisture in the lower troposphere, resulting in further intensification of the convective cells.

This article both joins with recent arguments in economic geography that have made connections between work on industrial symbiosis and agglomerative tendencies and recasts this work. Drawing on the case of Sitakunda-Bhatiary, Bangladesh, it shows that symbiosis is intricately bound up in the global circulation of wastes and their recovery through secondary processing. It draws attention to the importance of key places as conduits in the transformation of materials and secondary processing; emphasizes their importance as sites of symbiotic activity; and shows how such places exemplify economies of recycling, reuse, and remanufacturing, but in conditions of minimal environmental regulation. It therefore shows that contemporary symbiosis is not necessarily clean and green and may be very messy; that it can be generative of agglomerations, not just dependent upon prior agglomerations; that such agglomerations may be cross sectoral, not just interplant; and that symbiosis needs to be thought of not just through geographic proximity, but through the spatialities of globalization.

Cyclone Sidr had an intense rainband east of the cyclone center. The rainband exhibited two strong convective lines (band axes) composed of convective cells. To study the characteristics of the convective cells, a simulation was performed at 1-km resolution by using a cloud-resolving model. In both band axes, some cells showed the characteristic structure of a supercell. Supercells within the outer axis had stronger updraft, more intense precipitation, and a longer lifetime than those of the inner axis. The values of the CAPE and helicity are different in the strong vertical shear environment of the inner and outer axes. A large moisture flux was present throughout the troposphere on the east side of the outer axis. On the other hand, the upper level west of the inner axis was relatively dry. These are additional factors affecting the differences in cell characteristics in the two band axes.

The Mesoscale Convective Systems (MCSs) produce numerous weather hazards with their variety of forms. The formation mechanism of MCSs is thus important to know for Bangladesh and its surroundings, because this region is one of the heaviest rainfall areas in the tropical zone. The meteorologists are studying and analyzing the formation mechanism of different types of MCSs using radar and satellite observations data. Observations are limited to real time, but for planning purposes projected parameters over a certain period obtained from a mesoscale model is the requirement. Consequently, the motivation of this paper is to obtain the evolution and life cycle of MCSs developed in and around Bangladesh during pre-monsoon period through the simulation by a mesoscale model named MM5. In this work the calibration of MM5 model for different cumulus parameterization has been performed during the pre-monsoon period of this region. In the present study two domains with mesh resolutions 45 km × 45 km and 15 km × 15 km are prepared. MM5 runs using different cumulus parameterizations are carried out for sensitivity test. The precipitation simulated by the model are compared structurally and numerically with that of Tropical Rainfall Measuring Mission (TRMM) data products, available data from radar scan and observed rain-gauges rainfall in Bangladesh. Important features like lifetime, maintenance mechanism, traversed path, propagation speed and direction of MCSs developed during pre-monsoon period of 2002 in and around Bangladesh have been pointed out.

Feature extraction is an essential step of Optical Character Recognition. Accurate and distinguishable feature plays a significant role to leverage the performance of a classifier. The complexity level of feature identification algorithm differs for alphabet sets of different languages. Apart from generic algorithms to find features of different alphabet sets, these algorithms take care of individual characteristic common for a particular alphabet set. Dominant features of one alphabet set might completely differ from that of another set. Since there always remains the chance that inaccurate features may cause inefficient recognition, special attention should be given to identify the set of optimal features of a character set. Bengali characters also have some specific issues apart from the existing issues of other character sets. For example, there are about 300 basic, modified, and compound character shapes in the script, the characters in a word are topologically connected, and Bengali is an inflectional language. Literature survey shows that several authors have used different features and classification algorithms. The authors have extensively reviewed all these feature sets. In order to identify an optimal feature set, variability analysis has been proposed here. They focus on the specific peculiarities of Bengali alphabet sets, its different usage as vowel and consonant signs, compound, complex, and touching characters. The authors also took care to generate easily computable features that take less time for generation. However, more attention needs to be given in order to choose an efficient classifier.

Despite so many attempts to solve problems on several aspects of an OCR, a fully fledged solution is still unavailable for Bangle language. Problems that we have identified are summarized below. Little data are available as sample. So rigorous testing of an implementation is not possible. Each author has used their own set of data. As a result, comparative analysis does not produce a really meaningful result. Some authors addressed noise detection and cleaning phase in their works. However, a comprehensive solution for elimination of all types of noise is not available. The reader has already understood that Bangla has not only basic characters; it is rich with modifiers and compound characters. Placement of modifiers may happen on the upper, lower, left or right side of original characters which generates a lot of complications. Rarely authors could confidently claim that a particular segmentation and classification scheme has dealt with all of them. Again lack of standard or benchmark samples do not allow one to make a comprehensive testing of their application. Investigation of the phases of pattern recognition deserves special attention to be considered. We have done some component level implementation on Intel® Core™2 Duo processor with 4 GB RAM. Fig. 5.1a has been used as a sample image for binarization, segmentation, feature extraction, and classification. The total time length required for all the activities took from 1 minute to 10 minutes depending on the choice of algorithms. This suggests that careful investigation would reveal the best possible combination of algorithms and processes for all the phases of Bangla OCR. It is evident that a full commercial OCR is a demand of the time in this era of digitization.

Script segmentation is an essential and preprocessing task for any OCR system. Bangla is one of the most popular scripts in the world. Since segmentation effects the recognition process, accurate and proper segmentation is necessary to implement Bangla OCR. Many works have been done for both handwritten and printed Bangla text. This paper presents the segmentation process of different Bangla modifiers from printed Bangla words.