Predictive modeling of ion migration induced degradation in perovskite solar cells

With excellent efficiencies being reported from multiple labs across the world, device stability and the degradation mechanisms have emerged as the key aspects that could determine the future prospects of perovskite solar cells. However, the related experimental efforts remain scattered due to the lack of any unifying theoretical framework. In this context, here we provide a comprehensive analysis of ion migration effects in perovskite solar cells. Specifically, we show, for the first time, that (a) the effect of ionic charges is almost indistinguishable from that of dopant ions, (b) ion migration could lead to simultaneous improvement in Voc and degradation in Jsc - a unique observation which is beyond the realm of mere parametric variation in carrier mobility and lifetime, (c) champion devices are more resilient towards the ill effects of ion migration, and finally (d) we propose unique characterization schemes to determine both magnitude and polarity of ionic species. Our results, supported by detailed numerical simulations and direct comparison with experimental data, are of broad interest and provide a much needed predictive capability towards the research on performance degradation mechanisms in perovskite solar cellsComment: 8 pages, 5 figure

Utilization of CT scanning associated with complex spine surgery.

BackgroundDue to the risk associated with exposure to ionizing radiation, there is an urgent need to identify areas of CT scanning overutilization. While increased use of diagnostic spinal imaging has been documented, no previous research has estimated the magnitude of follow-up imaging used to evaluate the postoperative spine.MethodsThis retrospective cohort study quantifies the association between spinal surgery and CT utilization. An insurance database (Humana, Inc.) with ≈ 19 million enrollees was employed, representing 8 consecutive years (2007-2014). Surgical and imaging procedures were captured by anatomic-specific CPT codes. Complex surgeries included all cervical, thoracic and lumbar instrumented spine fusions. Simple surgeries included discectomy and laminectomy. Imaging was restricted to CT and MRI. Postoperative imaging frequency extended to 5-years post-surgery.ResultsThere were 140,660 complex spinal procedures and 39,943 discectomies and 49,889 laminectomies. MRI was the predominate preoperative imaging modality for all surgical procedures (median: 80%; range: 73-82%). Postoperatively, CT prevalence following complex procedures increased more than two-fold from 6 months (18%) to 5 years (≥40%), and patients having a postoperative CT averaged two scans. For simple procedures, the prevalence of postoperative CT scanning never exceeded 30%.ConclusionsCT scanning is used frequently for follow-up imaging evaluation following complex spine surgery. There is emerging evidence of an increased cancer risk due to ionizing radiation exposure with CT. In the setting of complex spine surgery, actions to mitigate this risk should be considered and include reducing nonessential scans, using the lowest possible radiation dose protocols, exerting greater selectivity in monitoring the developing fusion construct, and adopting non-ferromagnetic implant biomaterials that facilitate MRI postoperatively

The Factors That May Predict Response to Rituximab Therapy in Recurrent Focal Segmental Glomerulosclerosis: A Systematic Review

Recurrence of FSGS occurs in 30–40% of allografts. Therapies for recurrence are not well established. We retrieved all published reports depicting kidney transplant recipients with focal segmental glomerulosclerosis (FSGS) recurrence, treated with rituximab, to determine factors associated with treatment response. We found 18 reports of 39 transplant recipients who received rituximab. By univariate analysis for two outcomes (no response versus any response), fewer rituximab infusions and normal serum albumin at recurrence were associated with treatment response. For 3 outcomes (no response, partial and complete remission), male gender, fewer rituximab infusions, shorter time to rituximab treatment, and normal serum albumin were associated with remission. Multivariate analysis for both models revealed that normal serum albumin at FSGS recurrence and lower age at transplant were associated with response. Rituximab for recurrence of FSGS may be beneficial for only some patients. A younger age at transplant and normal serum albumin level at recurrence diagnosis may predict response

A Research Perspective on Data Management Techniques for Federated Cloud Environment

Cloud computing has given a large scope of improvement in processing, storage and retrieval of data that is generated in huge amount from devices and users. Heterogenous devices and users generates the multidisciplinary data that needs to take care for easy and efficient storage and fast retrieval by maintaining quality and service level agreements. By just storing the data in cloud will not full fill the user requirements, the data management techniques has to be applied so that data adaptiveness and proactiveness characteristics are upheld. To manage the effectiveness of entire eco system a middleware must be there in between users and cloud service providers. Middleware has set of events and trigger based policies that will act on generated data to intermediate users and cloud service providers. For cloud service providers to deliver an efficient utilization of resources is one of the major issues and has scope of improvement in the federation of cloud service providers to fulfill user’s dynamic demands. Along with providing adaptiveness of data management in the middleware layer is challenging. In this paper, the policies of middleware for adaptive data management have been reviewed extensively. The main objectives of middleware are also discussed to accomplish high throughput of cloud service providers by means of federation and qualitative data management by means of adaptiveness and proactiveness. The cloud federation techniques have been studied thoroughly along with the pros and cons of it. Also, the strategies to do management of data has been exponentially explored

Study of awareness of contraception in postnatal women

Background: This study was undertaken to know the awareness of contraception in postnatal women in a Government Hospital in Maharashtra.Methods: Authors conducted a prospective study in Department of Obstetrics and Gynecology at Government hospital, Miraj between January 2015 to September 2016. All postnatal patients in this hospital, willing to participate in the study were included in the study after a thorough written informed consent. Patients were given pre decided questions for answering. Answers were noted, counselling was done.Results: Out of 4860 women, 97% of the women were aware of at least 1 contraceptive method, the highest being of female sterilization (91%) 20.8% of women had ever used the contraception before and most of them used it in between pregnancies (64.4%). 79.2% had not used any contraception before and main reason for not using was found to be, they wanted to conceive (46%) followed by fear of side effects (24.7%) Regarding willingness to use the contraception after counselling, 48.5% of women said they were not sure. Among rest 51.4% women, female sterilization (32.4%) was preferred method followed by copper-T (22.8%) The most common source of information was by media and books which was 39.3%.Conclusions: There is a large lacuna between the awareness and practice of contraception. Proper education of both partners, increasing female literacy, socio economic upliftment, effective health care system is needed

Use of Analytical Hierarchy Process for Selection of Elective Subjects by Pre-Final Year Students of Computer Science

An eternally updating and enhancing nature of Information Technology and Communication leads to frequent revise of the curriculum syllabus in computer science courses, specifically in framing elective subjects for the courses of master degree. Choosing of preeminent elective subject by students depends on numerous parameters or criteria. This paper highlights the results of analysis of criteria which students considered for deciding on selection of elective subjects. The study assessed 12 subjects which are divided into two main heads - elective I and elective II. For this Analytical Hierarchy Process (AHP) technique was applied to evaluate the preference of students towards elective subjects. A list of five criteria was prepared to select the best elective subjects. These criteria are student interest, subject content, future application, factor of ease and peer?s choice. The outcome of the proposed research experiment shows that student gave more significance to ?Future Application? in selecting any of the elective subjects. Considering future application, ?Data Mining? and ?Android Programming ? I? are the subjects which gained maximum preferences considering the stated criteria