Analysis of Electrolyte Flow in Localized Electrochemical Deposition

AbstractLocalized electrochemical deposition (LECD) is a favorable technology for fabrication of the high-aspect ratio electrodes of various materials. This technology is found to be one of the simple and inexpensive ways to fabricate non-circular electrodes for micro-EDM. In order to fabricate non-circular electrodes a mask of non-conductive material is placed between the anode and cathode, which is immersed in a mixed electrolyte of copper sulfate, 1.0M sulfuric acid and as an additive agent 0.04 gm/liter of thiourea. The deposition of copper is localized on the cathode surface using a mask and applying ultra-short voltage pulses between the anode and cathode. In this set up the cathode is placed above the anode and mask, so that the deposited electrode can be used directly for EDM or any application without changing its orientation. In order to localize the deposited structure on the cathode surface, the electrolyte needs to flow through the mask and needs to touch the cathode and a constant flow rate of the electrolyte is maintained by using a pump. For this reason, micro holes of desired shapes are fabricated in the mask using micro milling. This study shows the effect of electrolyte flow through the micro holes of the mask and micro gap between the mask and anode on the microstructure of deposited electrode using FLUENT analysis. Moreover, an optimum range of electrolyte flow rate through the micro passages is also shown for the LECD process in order to fabricate high aspect ratio microstructures

Novel Robust Control of a 7-DOF Exoskeleton Robot

This paper proposes a novel robust control method for the control of a 7-DOF exoskeleton robot. The external disturbances and unknown dynamics in the form of friction forces, different upper-limb\u27s mass, backlash, and input saturation make robot unstable, which prevents the robot from correctly following the defined path. A new fractional sliding mode controller (NFSMC) is designed, which is robust against unknown dynamic and external disturbances. Fractional PID controller (FPID) has high trajectory tracking, but it is not robust against external disturbances. Therefore, by combining NFSMC and FPID controllers, a new compound fractional PID sliding mode controller (NCFPIDSMC) is proposed, which benefits high trajectory tracking of FPID and robustness of NFSMC. The stability of the proposed control method is verified by Lyapunov theory. A random noise is applied in order to confirm the robustness of the proposed control method

Detection of the recurrence of superficial urothelial carcinoma of urinary bladder by combined urine cytology and cystoscopy

The study was aimed to evaluate the accuracy of combined urine cytology and cystoscopy for the detection of the recurrence of superficial urothelial carcinoma of urinary bladder without bladder biopsy. A total 60 patients [males 48, females 12; age range 41-80 years (mean age- 63.15 years)] were included. Urine cytology as well as cystoscopy were done with a targeted biopsy taken from any apparently visible growth in the bladder. The systematic biopsy was taken where there was no growth. Reports of the cytology and cystoscopy were compared with the histopathology reports. It was found that 18 patients were cytology positive (false positive 2) and 42 patients were cytology negative (false negative 10) with sensitivity 61.5% and specificity 94%. During cystoscopy 24 patients were found recurrent growth in the bladder (false positive 3) and 36 patients were negative (false negative 5) with sensitivity 80.7% and specificity 91%. But when combined urine cytology and cystoscopic findings evaluated, the sensitivity and specificity were found 100% and 91% respectively. In conclusion, combined urine cytology and cystoscopy can be used for the detection of recurrence of superficial urothelial carcinoma of urinary bladder

Effects of Black Cumin (Nigella sativa L.) on patients with cancer and tumor: A systematic Review

Experimental studies demonstrated a positive effect of administration of Nigella sativa L. (Back cumin) and its active chemical components on cancer and tumor through the antioxidant and anti-cancer activity. This study aimed to determine the beneficial effect of the use of black cumin in patients with cancer and tumor. This systematic review includes 4 randomized controlled trials that investigated the effect of the administration of black cumin in human cancer. Articles were searched in PubMed, Cochrane library, Semantic scholar and directory of open access journal (DOAJ), open grey and grey literature report databases for studies from 1983 to 2020 before May using the following keywords, Nigella sativa, black cumin, cancer, tumor, etc. The results examined that N. sativa is much effective in treating breast cancer, gastrointestinal cancer, brain tumor, and acute myeloid leukemia. According to the limited evidence from the study, black cumin may have favorable effects on cancer and tumor. However, more research is needed on different types of cancer to confirm and establish the above findings.

Christmas Disease (Hemophilia B) A Case Report

We report a 25 years old man developed Haemarthrosis of left hip joint with a history of recurrent swelling and pain in multiple joints and prolonged bleeding following minor trauma since childhood. Subsequent investigations revealed Christmas disease (Haemophilia B). Hemophilia B is an X-linked bleeding disorder. This case emphasises the importance of considering a diagnosis of haemophilia in a man with unexplained bleeding, even in the absence of a positive family history. DOI: 10.3329/bsmmuj.v2i2.4766 BSMMU J 2009; 2(2): 90-9

Evaluation of various leakage current paths with different switching conditions

The Photovoltaic (PV) panel is the arrangement of solar cells that becoming famous in the world for commercial electric power market via transformer-less topology. However, non-existing galvanic isolation is the biggest problem occurred in the whole system and is known as leakage issue. In this paper, different paths of leakage current were analyzed with various wave shapes and ranges. Furthermore, it was also verified using DC decoupling and AC decoupling with full bridge rectifier. Moreover, the EMC filter and high range load were used to evaluate the performance. Moreover, here also shown the transfer function of EMC filter with its simulated figure

The new normal: changed patterns of dwelling demand and supply

This research assessed the impact of the COVID-19 pandemic on patterns of housing supply and demand and how the Australian housing market has changed over recent time (including between the 2016 and 2021 Censuses). The pandemic showed just how quickly demand for housing can change and how prices and rents can rise rapidly as a result. The COVID-19 period, defined as mid-2020 to mid-2022 for the purposes of this study, saw robust price growth within Australian capital cities and even stronger growth in regional areas. In the rental market, vacancy rates fell across the country and rents rose sharply.COVID changed what households want from their dwelling: predominantly it was about having more space, both inside and out, and that was linked with the ability to work more from home. Overall, consumers continue to prefer houses over units in metropolitan areas. COVID-19 also created significant and distinct changes to population dynamics with low or negative growth within inner urban areas; growth in regional towns and cities, particularly those associated with sea and tree changes; and strong growth in traditional first home buyer areas, primarily on the urban periphery.Property sales in high-growth regions came significantly from investors who sold stock from the rental market (generally to first home buyers and second home buyers). This, in turn, reduced rental availability and vacancy rates and displaced private renters. Where investors did buy into the regional areas studied, these were at higher prices which were in turn reflected in higher rents.The research reiterates that increases in housing supply need to be carefully managed by governments, including the supply of social and affordable housing in regional areas

An Ultra-Sensitive Visible-IR Range Fiber Based Plasmonic Refractive Index Sensor

Photonic crystal fiber (PCF)-based plasmonic sensors have gained considerable attention because of their highly sensitive performance and broad range of sensing regimes. In this work, a relatively simple ultra-sensitive PCF-based surface plasmon resonance (SPR) sensor has been proposed for detecting different analyte refractive indices (RIs) ranging from 1.33 to 1.43 over a wide range of wavelength spectrum spanning 0.55 $\mu$m to 3.50 $\mu$m. The comprehensive finite-element simulations indicate that it is possible to achieve remarkable sensing performances such as wavelength sensitivity (WS) and figure of merit (FOM) as high as 123,000 nm/RIU and 683 RIU$^{-1}$, respectively, and extremely low values of wavelength resolution (WR) of 8.13 x 10$^{-8}$ RIU. In addition, a novel artificial neural network (ANN) model is proposed to be integrated into the practical setup in order to accurately predict the RIs by carefully examining the simulation data. The mean square error (MSE) and accuracy ($R^2$) values for the ANN model are found about 0.0097 and 0.9987, respectively, indicating the high prediction capability of the proposed ANN model. Due to its exceptional sensitivity and precise detection capabilities, the proposed device has the potential to serve as a viable option for sensing analyte refractive index (RI). Additionally, the sensor could be utilized for identifying cancerous cells and detecting urinary tract infections in humans

Design and Development of an Upper Limb Rehabilitative Robot with Dual Functionality

The design of an upper limb rehabilitation robot for post-stroke patients is considered a benchmark problem regarding improving functionality and ensuring better human–robot interaction (HRI). Existing upper limb robots perform either joint-based exercises (exoskeleton-type functionality) or end-point exercises (end-effector-type functionality). Patients may need both kinds of exercises, depending on the type, level, and degree of impairments. This work focused on designing and developing a seven-degrees-of-freedom (DoFs) upper-limb rehabilitation exoskeleton called ‘u-Rob’ that functions as both exoskeleton and end-effector types device. Furthermore, HRI can be improved by monitoring the interaction forces between the robot and the wearer. Existing upper limb robots lack the ability to monitor interaction forces during passive rehabilitation exercises; measuring upper arm forces is also absent in the existing devices. This research work aimed to develop an innovative sensorized upper arm cuff to measure the wearer’s interaction forces in the upper arm. A PID control technique was implemented for both joint-based and end-point exercises. The experimental results validated both types of functionality of the developed robot

Ischemic Strokes: Observations from a Hospital Based Stroke Registry in Bangladesh.

Background. Stroke is an important morbidity for low and middle income countries like Bangladesh. We established the first stroke registry in Bangladesh. Methods. Data was collected from stroke patients who were admitted in Department of Neurology of BIRDEM with first ever stroke, aged between 30 and 90 years. Patients with intracerebral hemorrhage, subarachnoid and subdural hemorrhage, and posttrauma features were excluded. Results. Data was gathered from 679 stroke patients. Mean age was 60.6 years. Almost 68% of patients were male. Small vessel strokes were the most common accounting for 45.4% of all the patients followed by large vessel getting affected in 32.5% of the cases. Only 16 (2.4%) died during treatment, and 436 (64.2%) patients had their mRS score of 3 to 5. Age greater than 70 years was associated with poor outcome on discharge [OR 1.79 (95% CI: 1.05 to 3.06)] adjusting for gender, duration of hospital stay, HDL, and pneumonia. Age, mRS, systolic blood pressure, urinary tract infection, pneumonia, and stroke severity explained the Barthel score. Conclusion. Mortality was low but most of patient had moderate to severe disability at discharge. Age, mRS, systolic blood pressure, urinary tract infection, pneumonia, and stroke severity influenced the Barthel score