Comparative simulation of nonlinear radiative nano casson and maxwell fluids with periodic magnetic force and sensitivity analysis.

This study investigated cyclic magneto-hydrodynamic radiative effects in Casson and Maxwell fluids, including nonlinear radiation and Arrhenius activation energy. It promotes non-Newtonian fluid use in diverse fields like industry, manufacturing, sciences, medicine, and engineering. Using boundary layer approximations, non-dimensional equations are formulated. For numerical solutions, widely recognized explicit finite difference method (EFDM) has been utilized. To ensure the robustness of EFDM results, stability and convergence tests are performed. Exploration involve a detailed sensitivity analysis by using RSM, offering a thorough understanding of influential parameters. These analyses explore complex interactions among physical parameters, affecting Nusselt number, skin friction, and Sherwood number. Maxwell fluid's velocity is more affected by periodic magnetic force than Casson fluid, during the presence of nonlinear radiation. Additionally, nonlinear thermal radiation has a greater impact on temperature and concentration profiles compared to linear radiation for both fluids. Moreover, Casson fluid has a stronger influence on the average heat transfer rate compared to Maxwell fluid with nonlinear thermal radiation which is 8.6 % greater than the Maxwell fluid. On the other hand, at constant thermal radiation (Ra), due to decrease of Brownian motion (Nb), the rate of heat transfer is reduced by 1.2 % and 0.3 % respectively for Maxwell and Casson fluid. Also, for thermophoresis parameter (Nt), this rate is reduced by 2 % and 1.6 % respectively. The investigation also revealed that the Ra exhibits a positive sensitivity towards average Nusselt number, while Nb and Nt are displayed a negative sensitivity.

Numerical modeling of a MHD non-linear radiative Maxwell nano fluid with activation energy.

The present research explores linear as well as nonlinear radiation patterns based on the MHD non-Newtonian (Maxwell) nanofluid flow having Arrhenius activation energy. This study's core focus is MHD properties in non-Newtonian fluid dynamics and boundary layer phenomena analysis. It initiates with time-dependent equations, employing boundary layer approximations. Extensive numerical computations, executed with custom Compact Visual Fortran code and the EFD method, provide profound insights into non-Newtonian fluid behavior, revealing intricate force interactions and fluid patterns. To check the stability of the solution, a convergence and stability analysis is performed. With the values of ΔY = 0.25, Δτ = 0.0005, and ΔX = 0.20; it is found that the model convergence occurs to the Lewis number, Le > 0.016 as well as the Prandtl number, Pr > 0.08. In this context, investigating non-dimensional results that depend on multiple physical factors. Explanation and visual representations of the effects of different physical characteristics and their resultant temperatures, concentrations, and velocity profiles are provided. As a result of the illustrations, the skin friction coefficient and Sherwood number, which are calculated, as well as Nusselt values, have all come up in discussion. Additionally, detailed representations of isothermal lines and streamlines are implemented, and it is pointed out that the development of these features occurs at the same time as Brownian motion. Furthermore, the temperature field for Maxwell fluid is modified due to the impression of chemical reaction as well as the Dufour number (Kr and Du). Our research demonstrates the superior performance of non-Newtonian solutions, notably in cases involving activation energy and nonlinear radiation. This paradigm shift carries significant implications. In another context, the interplay between Maxwell fluid and nonlinear radiation is notably affected by activation energy, offering promising applications in fields like medicine and industry, particularly in groundbreaking cancer treatment approaches.

Fe-Pd nanoflakes decorated on leached graphite disks for both methanol and formic acid electrooxidation with excellent electrocatalytic performance.

This paper introduces a unique and simple method for fabricating of inexpensive electrocatalysts for use in direct methanol fuel cells. The leached Fe1-Pd1 NFs/graphite (leached Fe1-Pd1/graphite) disk electrode was successfully obtained via uniform dispersion of Zn powder into the matrix of commercial graphite powder (98%), pressing under optimized pressure followed by the treatment in H2SO4 solution containing Fe+2 and Pd+2 cations, leading to the partial leaching out of Zn from graphite matrix, as well as partial electroless substitution of Fe-Pd nanoflakes with Zn metal. Based on the morphology studies, binary Fe-Pd nanoflakes with a large surface area uniformly dispersed on the leached graphite disk. The leached Fe-Pd/G disk showed the exceptional electrocatalytic activity toward methanol and formic acid oxidation without electrocatalyst poisoning being observed, in contrast to the leached Pd/graphite and leached Fe/graphite disks. This is due to the high surface area, and synergistic effect of Pd and Fe. The findings of this work may be used for the mass manufacture of graphite-based disks for commercial fuel cell applications using available graphite powders. The linear range of washed Fe1-Pd1/G electrocatalyst for measuring methanol was about 0.1-1.3 M, and its detection limit was calculated at about 0.03 M. Furthermore, the linear range of the nanocatalyst for measuring formic acid was about 0.02-0.1 M, and its detection limit was calculated at about 0.006 M.

A 5.8 GHz 1.8 V +20 dBm 32.5% PAE Power Amplifier for a Short-Range Over-the-Air WPT Application.

This paper presents a 5.8 GHz differential cascode power amplifier for an over-the-air wireless power transfer application. Over-the-air wireless power transfer provides a variety of benefits in several applications such as the Internet of Things and medical implantation applications. The proposed PA features two fully differentially active stages with a custom-designed transformer to provide a single-ended output. The custom-made transformer shows a high quality factor, as high as 11.6 and 11.2 for the primary and secondary sides at 5.8 GHz. Fabricated using a standard 180 nm CMOS process, the amplifier achieves input and output matching of -14.7 dB and -29.7 dB, respectively. To achieve a high power level and efficiency, accurate optimization through power matching, Power Added Efficiency (PAE), and the design of the transformer are carried out while the supply voltage is limited to 1.8 V. Measurement results show a 20 dBm output power with a PAE as high as 32.5%, which makes the PA suitable for application, and it can be implanted while arrayed with various antenna arrays. Finally, a FOM is introduced to compare the performance of the work with similar works in the literature.

Evaluation of antioxidant properties of nanoencapsulated sage (Salvia officinalis L.) extract in biopolymer coating based on whey protein isolate and Qodumeh Shahri (Lepidium perfoliatum) seed gum to increase the oxidative stability of sunflower oil.

Sage leaf extract (SLE) is considered an excellent source of bioactive compounds mainly because of its high content of phenolics, widely known as natural antioxidants. This study aimed to compare the performance of free/encapsulated SLE by different coatings in protecting sunflower oil against oxidative deterioration. The coating materials were whey protein isolate and qodumeh seed gum at different ratios (1:0, 1:1, and 0:1). Each nanocapsule was analyzed for particle size, zeta potential, encapsulation efficiency, phenolics release, and SEM images. The total phenolic compounds of SLE were 31.12 mg GA/g. The antioxidant activity of SLE was increased in both DPPH and FRAP assays by increasing extract concentration from 50 to 250 ppm. All nanoparticles exhibited nanometric size, negative zeta potential, encapsulation efficiency higher than 60%, and gradual release during storage. The oxidative stability of sunflower oil with or without the incorporation of 250 ppm of free/encapsulated SLE was evaluated during 24 days of storage at 60°C. Peroxide value (PV), thiobarbituric acid value (TBA), oxidative stability index (OSI), color index (CI), and conjugated dienes (CD) were determined. COPM nanoparticles showed the lowest PV, TBA, CI, and CD but both SGUM and WHEY were more effective in delaying oil oxidation than TBHQ and free extract. Higher OSI was observed in oil-containing nanoparticles with composite coating. Results obtained reinforce the use of whey protein isolate and qodumeh seed gum as a coating for encapsulating SLE to increase the shelf life of sunflower oil as a natural antioxidant.

A High-Power 3P3T Cross Antenna Switch with Low Harmonic Distortion and Enhanced Isolation Using T-Type Pull-Down Path for Cellular Mobile Devices.

This paper presents a radio frequency (RF) triple pole triple throw 3P3T cross antenna switch for cellular mobile devices. The negative biasing scheme was applied to improve the power-handling capability and linearity of the switch by increasing the maximum tolerable voltage drop across the drain and source and reverse biasing the parasitic junction diodes. To avoid signal reflection through the antenna in off-state, all the antenna ports were equipped with 50-ohm termination to provide the pull-down path. Considering the simultaneous operation of antenna ports in different switch cases, the presented T-type pull-down path demonstrated improvement of isolation by over 15 dB. Using stacked switches, the 3P3T handled the input power level of over 35 dBm. The chip was manufactured in 65 nm complementary metal oxide semiconductor (CMOS) silicon on insulator (SOI) technology with a die size of 790 × 730 µm. The proposed structure achieved insertion loss, isolation, and voltage standing wave ratio (VSWR) of less than -0.9 dB, -40 dB, and 1.6, respectively, when the input signal was 3.8 GHz. The measured results prove the implemented switch shows the second and third harmonic distortion performances of less than -60 dBm when the input power level and frequency are 25 dBm and 3.8 GHz, respectively.

A 1.8-2.7 GHz Triple-Band Low Noise Amplifier with 31.5 dB Dynamic Range of Power Gain and Adaptive Power Consumption for LTE Application.

This paper presents a multi-gain radio frequency (RF) front-end low noise amplifier (LNA) utilizing a multi-core based on the source degeneration topology. The LNA can cover a wide range of input and output frequency matching by using a receiver (RX) switch at the input and a capacitor bank at the output of the LNA. In the proposed architecture here, to avoid the saturation of RX chain, 12 gain steps including positive, 0 dB, and negative power gains are controlled by a mobile industry processor interface (MIPI). The multi-core architecture offers the ability to control the power consumption over different gain steps. In order to avoid the phase discontinuity, the negative gain steps are provided using an active amplification and T-type attenuation path that keeps the phase discontinuity below ±5 degrees between two adjacent power gain steps. Using the multi-core structure, the power consumption is optimized in different power gains. The structure is enhanced with the adaptive variable cores and reactance parameters to maintain different power consumption for different gain steps and remain the output matching in an acceptable operating range. Furthermore, auxiliary linearization circuitries are added to improve the input third intercept point (IIP3) performance of the LNA. The chip is fabricated in 65 nm complementary metal-oxide semiconductor (CMOS) silicon on insulator (SOI) process and the die area is 0.308 mm2. The proposed architecture achieves the IIP3 performance of -10.2 dBm and 8.6 dBm in the highest and lowest power gains, which are 20.5 dB and -11 dB, respectively. It offers the noise figure (NF) performance of 1.15 dB in the highest power gain while it reaches 14 dB when the power gain is -11 dB. The LNA consumes 16.8 mA and 1.33 mA current from a 1 V power supply that is provided by an on-chip low-dropout (LDO) when it operates at the highest and lowest gains, respectively.

A Dual-Band 47-dB Dynamic Range 0.5-dB/Step DPA with Dual-Path Power-Combining Structure for NB-IoT.

This paper presents a digital power amplifier (DPA) with a 43-dB dynamic range and 0.5-dB/step gain steps for a narrow-band Internet of Things (NBIoT) transceiver application. The proposed DPA is implemented in a dual-band architecture for both the low band and high band of the frequency coverage in an NBIoT application. The proposed DPA is implemented in two individual paths, power amplification, and power attenuation, to provide a wide range when both paths are implemented. To perform the fine control over the gain steps, ten fully differential cascode power amplifier cores, in parallel with a binary sizing, are used to amplify power and enable signals and provide fine gain steps. For the attenuation path, ten steps of attenuated signal level are provided which are controlled with ten power cores, similar to the power amplification path in parallel but with a fixed, small size for the cores. The proposed implementation is finalized with output custom-made baluns at the output. The technique of using parallel controlled cores provides a fine power adjustability by using a small area on the die where the NBIoT is fabricated in a 65-nm CMOS technology. Experimental results show a dynamic range of 47 dB with 0.5-dB fine steps are also available.

Evaluation of Short Term Outcome of Stapled Transanal Rectal Resection (STARR) for ODS (Obstructed Defecation Syndrome) by Comparing Pre and Post-operative ODS Score.

Obstructed defecation syndrome (ODS) is a common anorectal problem and it can be corrected by various surgical approaches but most of these have high recurrence and complication rates. Antonio Longo introduced Stapled transanal rectal resection (STARR) in 2003 as a minimally invasive transanal operation for correction ODS associated with rectocele and or rectal intussusception. This study was designed to assess the short term outcome of Stapled Transanal Rectal Resection (STARR) as a surgical treatment of Obstructed Defecation Syndrome (ODS). This is a quasi experimental study which was carried out in the department of Colorectal Surgery, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh from May 2016 to June 2017. Seventeen (17) patients were included in the study. Patients with obstructed defecation syndrome and rectocele and or rectal intussusception admitted in the department of Colorectal Surgery were enrolled in the study as per inclusion and exclusion criteria. History, clinical examination, Proctoscopy, Colonoscopy and MR Defecography was done for evaluation of the patients. During evaluation preoperative Longo's ODS score of every patient also determined and compared with postoperative ODS score. The patient was followed up regularly at one, three and six months after each operation. The ODS score in 82.35% patients improved significantly. The postoperative score was high (13-15) only in 02(11.8%) patients probably due to presence of physiological factors. Post-operative defecatory urgency was developed in only 02(11.76%) patients. Major postoperative complication like hemorrhage or rectovaginal fistula did not develop in any patient. STARR is an effective, less invasive and simple procedure for the treatment of ODS with rectocele and/or rectal intussusception without major morbidity but other physiological causes of ODS should exclude preoperatively because its presence makes the surgical intervention fruitless.

A 0.617-2.7 GHz Highly Linear High-Power Dual Port 15 Throws Antenna Switch Module (DP15T-ASM) with Branched-Antenna Technique and Termination Mode.

This paper presents a Dual-Port-15-Throw (DP15T) antenna switch module (ASM) Radio Frequency (RF) switch implemented by a branched antenna technique which has a high linearity for wireless communications and various frequency bands, including a low- frequency band of 617-960 MHz, a mid-frequency band of 1.4-2.2 GHz, and a high-frequency band of 2.3-2.7 GHz. To obtain an acceptable Insertion Loss (IL) and provide a consistent input for each throw, a branched antenna technique is proposed that distributes a unified magnetic field at the inputs of the throws. The other role of the proposed antenna is to increase the inductance effects for the closer ports to the antenna pad in order to decrease IL at higher frequencies. The module is enhanced by two termination modes for each antenna path to terminate the antenna when the switch is not operating. The module is fabricated in the silicon-on-insulator CMOS process. The measurement results show a maximum IMD2 and IMD3 of -100 dBm, while for the second and third harmonics the maximum value is -89 dBc. The module operates with a maximum power handling of 35 dBm. Experimental results show a maximum IL of 0.34 and 0.92 dB and a minimum isolation of 49 dB and 35.5 dB at 0.617 GHz and 2.7 GHz frequencies, respectively. The module is implemented in a compact way to occupy an area of 0.74 mm2. The termination modes show a second harmonic of 75 dBc, which is desirable.

External versus Endoscopic Dacryocystorhinostomy for Primary Acquired Nasolacrimal Duct Obstruction.

PURPOSE: The purpose of the study is to compare the surgical outcomes and success rates of external dacryocystorhinostomy (EX-DCR) versus endoscopic endonasal DCR (EN-DCR) for the treatment of primary acquired nasolacrimal duct obstruction (PANDO). METHODS: This retrospective nonrandomized study was conducted at Farabi Eye Hospital and Noor Eye Hospital, Iran. A review of electronic medical records of all patients with PANDO who underwent EX-DCR or EN-DCR between January 2016 and 2018 was carried out. RESULTS: A total of 803 patients underwent surgery, of which 618 patients (77%) were managed by EX-DCR and 185 patients (23%) by EN-DCR. The majority of cases (62%) were female. The mean age of the patients in EX-DCR and EN-DCR groups was 40.8 ± 14.2 and 34.3 ± 9.2 years, respectively. EX-DCR resulted in significantly less amount of pain compared to EN-DCR (P < 0.05). The success rate of surgery among EX-DCR and EN-DCR groups was 92.4% and 91.1%, respectively, and did not show statistically significant difference. A higher incidence of intraoperative hemorrhage requiring intervention was noted in the EN-DCR group (16.7% vs. 4.5%). Postoperative patient's satisfaction with EN-DCR and EX-DCR was 73% and 82%, respectively. CONCLUSION: Both EX-DXR and endoscopic DCR surgeries have high success rates and low incidence of failure. The choice of DCR technique should be based on the experience of the surgeon and patient's lacrimal and nasal anatomy and preferences.

A 77-dB Dynamic-Range Analog Front-End for Fine-Dust Detection Systems with Dual-Mode Ultra-Low Noise TIA.

This paper presents an analog front-end for fine-dust detection systems with a 77-dB-wide dynamic range and a dual-mode ultra-low noise TIA with 142-dBΩ towards the maximum gain. The required high sensitivity of the analog signal conditioning path dictates having a high sensitivity at the front-end while the Input-Referred Noise (IRN) is kept low. Therefore, a TIA with a high sensitivity to detected current bio-signals is provided by a photodiode module. The analog front end is formed by the TIA, a DC-Offset Cancellation (DCOC) circuit, a Single-to-Differential Amplifier (SDA), and two Programmable Gain Amplifiers (PGAs). Gain adjustment is implemented by a coarse-gain-step using selective loads with four different gain values and fine-gain steps by 42 dB dynamic range during 16 fine steps. The settling time of the TIA is compensated using a capacitive compensation which is applied for the last stage. An off-state circuitry is proposed to avoid any off-current leakage. This TIA is designed in a 0.18 µm standard CMOS technology. Post-layout simulations show a high gain operation with a 67 dB dynamic range, input-referred noise, less than 600 fA/√Hz in low frequencies, and less than 27 fA/√Hz at 20 kHz, a minimum detectable current signal of 4 pA, and a 2.71 mW power consumption. After measuring the full path of the analog signal conditioning path, the experimental results of the fabricated chip show a maximum gain of 142 dB for the TIA. The Single-to-Differential Amplifier delivers a differential waveform with a unity gain. The PGA1 and PGA2 show a maximum gain of 6.7 dB and 6.3 dB, respectively. The full-path analog front-end shows a wide dynamic range of up to 77 dB in the measurement results.

Role of Intraperitoneal Normal Saline Instillation in Relieving Post-operative Pain Following Laparoscopic Cholecystectomy: A Quasi Experimental Study.

Laparoscopic cholecystectomy has rapidly become the procedure of choice for the treatment of calculus cholecystitis for having clear advantage over open method in reducing surgical morbidity, postoperative pain and complication. But still patients undergoing laparoscopic cholecystectomy complain of considerable pain especially on first post-operative day necessitating use of better methods for postoperative analgesia. This quasi experimental study was done in Surgery Unit III, Mymensingh Medical College Hospital from July 2016 to June 2017 to assess the role of intraperitoneal normal saline instillation following laparoscopic cholecystectomy in relieving postoperative pain. In this study total 200 patients of calculus cholecystitis were enrolled according to inclusion and exclusion criteria and assigned equally into two groups by non-equivalent control group design. Both the control group and experimental group were managed according to the standard protocol and operated in routine operation theater. The experimental group (n=100) was additionally instilled with 25-30ml/kg body weight of normal saline at 37°C at the gallbladder bed and subdiaphragmatic space at the end of surgery and all the data were recorded in individual case record form. Among the sample most of the patients were between 25-60 years of ages with the peak age being between 43-51 years. Eighty one percent (81%) of the total patients were female with male female ratio being 1:5.25 in Control group and 1:3.54 in Experimental group. The VAS scores for visceral pain in experimental group were significantly less than that of control group at 6 hours (p<0.001), 12 hours (p<0.001), 24 hours (p<0.001) and 48 hours (p=0.026). The VAS scores for shoulder tip pain in experimental group were also significantly less than that of control group at 6 hours (p<0.001), 12 hours (p<0.018) and 24 hours (p=0.004). The administration of analgesics was also significantly less in the experimental group than in control group at 6 hours (p<0.001), 12 hours (p<0.001), 24 hours (p=0.313) and 48 hours (p=0.297) with no significant differences at 72 hours. The mean hospital stay in this study was 2.2±0.7 days in the control group and 2.1±0.8 days in the experimental group showing no significant difference (p>0.05). Intraperitoneal normal saline instillation following laparoscopic cholecystectomy may be an eminent choice for reducing postoperative pain improving patient's experience.

Outcome of Management of Liver Abscess by Surgical Approach in a Tertiary Care Hospital.

Liver abscess is a serious, life threatening condition. A recent development in the management of liver abscesses, facilitated by advances in diagnostic and interventional radiology, has decreased mortality rates. The purpose of this study is to search for the clinical presentations and surgical outcomes of liver abscess in our country. The markers of the outcome are mortality, duration of hospital stay and complications such as wound infection, residual disease following surgery, biliary leakage, intra abdominal abscess formation. This observational cross sectional study was conducted in Mymensingh Medical College & Hospital (MMCH), Bangladesh for 12 months from 1st January 2017 to 31st December 2017. Total 25 patients presenting with the features of liver abscess were included in this study by convenient and purposive sampling according to the inclusion and exclusion criteria. Surgical principles of liver abscess management were applied and outcomes were observed. The patients were diagnosed on the basis of clinical feature, findings of abdominal ultrasound and occasionally by doing CT scan. Most of the patients (28%) were in the age group of 51-60 years. Regarding sex distribution majority of the patients (64%) was male. Most of patients presented with fever (92%), anorexia and vomiting (32%), upper abdominal pain (84%). Hepatomegaly and reactive pleural effusion are the important findings present in 9(36%) and 8(32%) patients respectively. Size of the liver abscess was more than 5cm in 72% patients. Among the patients right lobe was predominantly involved. It was found during laparotomy that 4 patients (16%) had spontaneous rupture of abscess into peritoneal cavity. One (4%) patient developed biliary leakage after surgical drainage. No intra abdominal abscess or residual diseases was observed after surgery. Among the patients 24% developed wound infection. The overall mortality rate was 12%. The median length of hospital stay was 8 days (range: 1-15 days). Outcome of surgical drainage of liver abscess in tertiary care hospital of our country shows satisfactory result. So, patients with large multiple liver abscess, septic shock, failures of percutaneous drainage should be treated by early open surgical intervention.

Effectiveness of Pressurized Normal Saline Irrigation of Subcutaneous Tissue Following Appendicectomy in Decreasing Wound Infection: A Quasi Experimental Study.

Acute appendicitis is the commonest cause of acute abdomen necessitating surgical intervention and wound infection is the most frequently encountered complication following appendicectomy. To assess the effectiveness of pressurized normal saline irrigation of subcutaneous tissue following appendicectomy in decreasing wound infection this quasi experimental study was done in Surgery Unit III, Mymensingh Medical College Hospital from January 2018 to December 2018. In this study total 200 patients of acute appendicitis were enrolled according to inclusion and exclusion criteria and assigned equally into two groups by non-equivalent control group design. In control group all the standard protocol of wound closure following appendicectomy was followed and in experimental group along with the standard protocol the subcutaneous tissue was irrigated by pressure with normal saline and all the data were recorded in individual case record form. Among the sample most of the patients were between 10-19 years of ages and the male female ratio was 1.38:1. In control group 30% patients developed wound infection while 12% patients developed wound infection in experimental group with a P value of 0.027. Mean hospital stay of experimental group was less than the control group (P value less than 0.05). Overall postoperative outcome in context of wound infection and hospital stay is better following pressurized normal saline irrigation of subcutaneous tissue during closure.

Efficacy of Intra-peritoneal Tramadol Instillation for Postoperative Pain Management after Laparoscopic Cholecystectomy.

Gall stone disease is one of the most common conditions encountered in general surgical practices in adult population. The gold standard treatment for symptomatic gall stone disease is laparoscopic cholecystectomy. It results in less post-operative pain as compared to open cholecystectomy but post-operative pain may be mild, moderate or even severe in some patients. This Randomized control trail was conducted to In-patient department of Surgery, Mymensingh Medical College & Hospital (MMCH), Mymensingh, Bangladesh from April 2018 to September 2018. It was undertaken to evaluate the analgesic effect of intra-peritoneal tramadol instillation in patients undergoing laparoscopic cholecystectomy. Total 70 patients with symptomatic gallstone disease undergoing laparoscopic cholecystectomy were randomized equally in two groups. Then patients were selected in according to the inclusion and exclusion criteria. In first group (Group A), patients were received intra-peritoneal tramadol 100mg (diluted in 20.0ml distilled water). Sprayed 10.0ml diluted tramadol into the sub diaphragmatic area, 5.0ml into the area of gall bladder bed and 5.0ml into the space between the liver and kidney under direct vision just before removal of trocars. In second group (Group B) the conventional operative procedure was followed. Postoperatively, patient was extubated and shifted to recovery room. Data recorded and analyzed, such as post-operative pain score at 1, 4, 8, and 24 hour; cumulative 1, 8 and 24 hour analgesic consumption. In addition that postoperative hospital period monitoring of heart rate, blood pressure, respiratory rate, temperature at 0, 4, 8, 24 hours was also analyzed. Intensity of pain was assessed by Visual Analogue Scale (VAS) scoring system. Patients showed a VAS ≥3 or patients who requested for analgesia was administrated a supplemental dose of analgesic. In the present study the mean pain scores in Group A were found to be low at1hourpost-operative was 0.60±0.56 and there was a gradual increase in score in respect of time interval with peak of 2.07±0.91 at 24 hours. Whereas, in Group B the mean pain scores immediate post-operative period were at its peak was, 2.50±0.82 which decreased to 1.30±0.84 at 1 hour and further there was rise at 4 hours (2.10±0.71) and 24 hours (2.33±0.0.71). But at any point of time the mean VAS remained significantly low (p<0.050) in patients with Group A compared to Group B except at 1st 24 hours (p=0.210). Intra-peritoneal instillation of tramadol for postoperative pain control in laparoscopic cholecystectomy has beneficial effect in terms of postoperative pain relief following laparoscopic cholecystectomy.

Mesenteric Fibromatosis: A Case Report.

Fibromatosis of mesentery is a very rare disease and only a few cases have been reported. Here we report a case of 40 year old man admitted on 16 October, 2017 in the Department of Surgery (Unit-3) of Mymensingh Medical College Hospital with history of recurrent abdominal pain and progressively enlarging intra-abdominal lump for 2 years. Out of different diagnostic dilemmas, finally we came to the conclusion of its being a mass lesion primarily arising from the mesentery and involving the adjoining gut according to the report of CT abdomen. Laparotomy was performed and a lump measuring about 18 cm × 20 cm arising from mesentery was found, in which distal part of jejunum and proximal part of ileum were embedded. The mass was excised with incorporated gut loops and histopathology report revealed fibromatosis of mesentery.

Clinicopathological Study of Enterocutaneous Fistula in Mymensingh Medical College Hospital.

Enterocutaneous fistulae are a major catastrophe to the patients and surgeons and it still has high incidence of morbidity and mortality and their management remains a big challenge. Enterocutaneous fistula presents the surgeon with challenges of metabolic disorders and extensive sepsis. Total management of an intestinal fistula requires skill in nutritional support, stoma therapy, elimination of sepsis, well timed and well carried out surgery. Postoperative enterocutaneous fistulae account for approximately 80% of enterocutaneous fistulae. The majority of the intestinal fistula (75-85%) is iatrogenic occurring in the postoperative period following anastomotic dehiscence. They arise following emergency abdominal surgery for intestinal obstruction, inflammatory bowel disease or cancers. Protein calorie malnutrition alters the patients immune response, inflammatory reactions and tissue regenerations, all of which are essential for wound repair. The present study is an effort to highlight the incidence of enterocutaneous fistula after emergency and elective resection and anastomosis of gut with discussion over recent trends and developments in its management and compare with other studies. Objectives of the study are to determine the various clinicopathological features and management protocol of enterocutaneous fistula. There are recent advances in nutritional support. This descriptive type of cross-sectional study was carried out in the Department of Surgery, Mymensingh Medical College and Hospital, Mymensingh, Bangladesh from October 2010 to September 2011. Total 42 cases of enterocutaneous fistulae were selected purposively. Enterocutaneous fistulae are more common in patients of low economic condition. Enterocutaneous fistulae are more common after emergency abdominal surgery. Spontaneous closure occurred in 17(40.48%) cases and surgery needed in 25(59.52%) cases. Of them 20(80.00%) were healed and 5(20.00%) were expired. In spite of improvement in the management protocol of enterocutaneous fistula, there is still high unacceptable morbidity and mortality rate. Total parenteral nutrition (TPN) is not available and very costly, and health care facilities are also limited in our country. Patients with enterocutaneous fistula require fluid, electrolytes and nutritional support. Anaemia, dehydration, electrolytes imbalance should be corrected prior to abdominal surgery if possible. Surgical treatment for enterocutaneous fistula should be performed only after failure of conservative treatment of more than 12 weeks.

Synthesis of MnO2 on Activated Carbon and its Potential Application in the Adsorption of As(V) and Pb(II) in Aqueous Solutions.

The conditions for the synthesis of a material with MnO2 (OMD) on activated carbon (AC) were studied. These conditions were: reaction time, temperature, stirring speed, concentrations of AC, H2SO4, and O3 in solution, and particle size. Agglomerates on AC were observed by means of scanning electron microscopy (SEM) and microanalysis by energy dispersive spectroscopy (EDS) and revealed the presence of OMD deposited on the surface. The activation energy and the factor of frequency for the reaction were determined as Ea = 1.2 kcal/mol and A = 2.2. The value of Ea indicates that the precipitation of OMD on the AC was controlled by mass transfer in aqueous solution and the order of reaction was zero. The adsorption capacities of AC were q = 14 mg Pb(II)/g AC and q = 9.1 mg As(V)/g AC. Whereas, for the OMD/AC obtained in the following conditions: [AC] 1 or 2 g/L, particle size of AC of +0.59 mm, [H2SO4] 1 or 2 mol/L, 25 °C, stirring speed 600 rpm, and [O3] 1.35 mol/L, the adsorption capacities were q = 90.5 mg Pb(II)/g OMD/AC and 25.4 mg As(V)/g OMD/AC. Therefore, the fixing of OMD on the surface of the AC greatly improved the removal of both Pb(II) and As(V) from aqueous solutions.

Early Outcome of Primary Repair in Colonic Injury.

The management of the colon injury remains controversial in spite of a number of divergent reports during the past decade. Previously surgeons were reluctant to do primary anastomosis but now-a-days they are doing primary repair with good results. The present study is designed to see the early outcomes of primary repair in colonic injury. This prospective observational study performed at Dhaka Medical College Hospital, Dhaka, Bangladesh from January 2013 to June 2013 with allocation of 50 patients with colonic injury who underwent laparotomy with primary repair of that injury in the department of Casualty Surgery. A primary repair was performed after freshening the edges or by resection and primary anastomosis with 3.0 round-body Vicryl by single layer extra mucosal interrupted suture. Data processed using software SPSS version 16.0. For all analytical results a p value <0.05 was considered significant. In this study the commonest site of injury were transvers colon and sigmoid colon 38.0% in each. Out of 50 respondents, 5(10.0%) developed burst abdomen, 1(2.0%) developed entero-cutaneous fistula with none had paralytic ileus or septicaemia or pelvic collection. No mortality observed. This study showed that the increasing in colon injury scale (CIS) score culminate into increasing rate of postoperative complication & post operative complications were more at left colon (24%). On basis of our findings, we recommend the primary repair is a safe and effective surgical technique for addressing the large gut injury. Unnecessary proximal diversions should be avoided. According to our experience, we believe that the policy of primary repair of colon injuries can be applied more liberally in majority of patients with high success rate.