Background: Ventral hernia repair is one of the most common surgical operations performed all over the world. Onlay and sublay mesh repairs are the commonly performed techniques for the same. However, the debate still continues about the superiority of both techniques over each other. The aim of this study was to compare the outcome of the onlay versus sublay mesh repair for ventral hernia.Methods: A total of 100 patients with paraumbilical, epigastric, supraumbilical and incisional hernias (with defect size ≤4 inches) were divided into main two groups; A: onlay mesh repair and B: sublay mesh repair. Patients with uncontrolled diabetes and recurrent ventral hernia were excluded. Randomization was done using computer generated software. Patients were evaluated for operating time, postoperative seroma formation, wound infection, drain duration, post-op hospital stay and recurrence of symptoms. Ethical approval for this study was granted by the ethical review committee of Mysore Medical College, Mysore, Karnataka, India.Results: The incidence of post-operative seroma and wound infection was 6.52% and 4.35% in sublay group compared to 21.30% and 19.20% in onlay group which was statistically significant (p<0.05). Mean operating time was found to be more in sublay group than onlay group which was also statistically significant (72.3+9.23 vs. 65.25+10.58 minutes, p<0.05). Mean drainage duration (4.22+0.99 days vs. 5.97+1.24 days) and post-op hospital stay (4.8+1.51 days vs. 6.68+1.46 days) was low in sublay group compared to onlay group which was statistically significant (p<0.05). Recurrence in sublay group was 4.35% compared to 8.51% in onlay group which was not statistically significant (p>0.05).Conclusions: Even though operating time is longer, placement of mesh in sublay position is a better option than onlay placement in open ventral hernia repair because of lower complication rate and post-op morbidity.

Wind energy and Solar energy, are considered to be the main attributes of renewable energy for electricity generation, are growing at faster rate for the last two-three decades. This paper pertains to the study of a novel integration of wind energy from grid connected Permanent Magnet Synchronous Generator (PMSG) and solar energy systems. In order to extract maximum power from Wind energy and solar energy systems a novel technique, known as Maximum Power Point Tracking (MPPT) technique, has been adopted, in this paper. Additionally, to maintain and sustain the continuity of supply to the load on demand at all times, the outputs of wind energy and solar energy are integrated suitably. For wind generator, the overall operation is based on the estimation of the speed, that is basically a sensor-less rotor speed estimator, which in fact avoids all mechanical sensors. The rotor speed so estimated, is used to control the turbine speed by maintaining the input dc quantities (Voltage and Current) for boost converter. Simulation studies of the proposed system are carried out using MATLAB / Simulink platform, and results are presented.

ABSTRACT:The objective in this paper is to study the operating modes and analysis of the Switched Boost Inverter (SBI). The performance of the proposed SBI is similar to that of Z-Source Inverter (ZSI). In comparison to the ZSI, the present topology results in lower volume and lower cost since it reduces the number of passive component. This feature makes it more suitable for low power applications than ZSI.For the proper operation of the inverter, with special consideration to its operating principle (shoot-through i.e., conduction of two switches on the same leg of the inverter), a modified PWM control strategy is also described in detail. In addition, mathematical relations between various performance parameters under this modified PWM technique have been described in detail.Simulation is carried out using Matlab/Simulink software to verify the theoretical analysis made. This report also presents a laboratory prototype of the Switched boost inverter along with it results.KEYWORDS: Z-Source Inverter, Switched Boost Inverter, Modified PWM technique, Shoot-through, Non-Shootthrough. I.INTRODUCTIONZSI employs a unique impedance network to couple the converter circuit to the power source, thus providing unique characteristic features that cannot be found in the traditional Voltage source inverter and Current source inverter. The unique impedance network mentioned above, implements two capacitors and two inductors. Introduction of these passive components add weight and size to the whole inverter. In order to reduce size and weight, a new topology is considered which involves lesser passive components, meanwhile trying to attempt similarity in all the steady state performance. This new topology is called Switched Boost inverter, which is being studied and analysed in this report. II. LITERATURE SURVEYThe basic idea of SBI [2] is derived from ZSI [1]. By controlling the shoot-through duty cycle, the ZSI can be able to produce any AC output voltage from a given DC input voltage. This feature makes the ZSI suitable for number of applications such as renewable power systems (photovoltaic and fuel cells), adjustable speed drives, general purpose motor drives, electric vehicles, uninterruptible power supplies [3]-[8] etc.Conventional pulse-width modulation techniques can be modified strategically to affect the operation of ZSI continuously or discontinuously, while retaining all the harmonic performance features of the conventional modulation techniques [9]. The complete analytical performance of the ZSI using X-shaped LC impedance network is complicated. Hence a small signal model method is resorted in [10] to derive transfer function and asses the performance there upon. From literature survey it is evident that ZSI is a promising technology for both buck and boost operations. But ZSI has the drawback of employing more and bulky passive components. Therefore SBI topology has been proposed [2] to reduce the number of passive components, thus can be used in low power applications where size and weight matters.

Background: Though colonoscopy is widely performed, the statistical data regarding its indications, findings, and the diagnostic yield are not widely documented especially in developing countries. This study is an attempt to determine such data in a group of patients who underwent colonoscopy at our hospital.Methods: This was a hospital‑based retrospective study carried out at the Department of General Surgery, MMC&RI, Mysore. The subjects were a total of 286 patients who underwent colonoscopies in the year 2017. The relevant data from colonoscopy register were recorded and tabulated.Results: The major indications in our study group were bleeding per rectum (25%), unexplained diarrhoea or dysentery (16%), pain abdomen (15%) and suspected malignancy (13%). Other indications included suspected inflammatory bowel disease (IBD), subacute intestinal obstruction, anaemia, mass per abdomen and suspected irritable bowel syndrome (IBS). More than one third (35%) had normal colonoscopic studies. The most common pathology found was malignancy (24%) followed by the spectrum of proctocolitis (20%). The indications which produced high diagnostic yields included suspected carcinoma (97%), bleeding per rectum (82%) and suspected IBD (80%). Significant number of patients with per rectal bleeding was diagnosed with malignancy (21%). The indications which produced low yields included subacute intestinal obstruction (31%), anaemia (45%), non-specific pain abdomen (50%) and suspected irritable bowel syndrome (18%).Conclusions: Colonoscopy is highly rewarding among patients who are being evaluated for suspected malignancies, lower gastrointestinal bleeding and suspected IBD. As such, certain indications produce a higher diagnostic yield than others, suggesting that a stricter patient selection criterion may be employed for performing colonoscopy especially in resource poor settings.

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