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The progress of perovskite solar cell (PSC) technology is held back due to the presence of anomalous hysteresis in its current–voltage (J–V) characteristics. Understanding the physical origin of J–V hysteresis is crucial for the development of hysteresis-free solar cell. We computationally explore the relative contribution of dominant physical phenomenon that could cause hysteresis in PSC. We explore that accumulation of mobile ions at the interfaces of the cell inside perovskite produces a space charge which in combination with charge trapping/detrapping in deep traps results in hysteresis which is often characterized by an S shaped behavior of J–V curve. We further explore that shallow traps at the interfaces of carrier-extraction layers alone exhibit the combined effects of ion accumulation and deep charge traps, and lead to J–V hysteresis in PSCs. Moreover, we investigate the effect of energy level of deep/shallow traps and show that the energy level of deep/shallow traps plays an important role in J–V characteristics of the cell. Lastly, we explore that high minority carrier lifetime in the bulk of the perovskite mitigates the effects of ion accumulation and/or charge trapping/detrapping and leads to hysteresis-free cell. The results presented in this work are beneficial for the development of hysteresis-free PSCs.

Indoor photovoltaics (IPV) has recently emerged as a sustainable and reliable energy technology to power the rapidly growing Internet of Things. Among various solar cell technologies, emerging perovskite solar cells (PSCs) have gained great interest for IPV; owing to their unique optoelectronic properties such as bandgap tunability to efficiently harvest the indoor light spectrum. The choice of hole transport layer (HTL) is critical for efficient PSCs, particularly in IPV applications to reduce the parasitic absorption losses in the indoor light spectrum. Here, we explore the potential of CuSCN to be used as a HTL for PSCs in IPV applications. We show that CuSCN-based PSC exhibits remarkable power conversion efficiency (η) as compared to PSCs using conventional PEDOT:PSS as HTL. We explore the effects of wavelength (λ) of incident photons and various design parameters of PSC for optimal cell operations. We show that at a particular perovskite thickness, CuSCN-based PSC exhibits ∼8%–12% higher η than that for PEDOT-based PSC, for all λ in the visible range of the spectrum. We further explore the effect of HTL doping/thickness on PSC performance and show that CuSCN-based PSC performs optimally for a wide range of doping/thickness of HTL. We also find that CuSCN-based PSC outperforms PEDOT-based PSC for a broad range of incident irradiance. Finally, we show that for large values of λ (i.e. λ = 700 nm), η exceeds 30%, close to the highest ever in the past work. The work presented in this study will provide guidance for the development of efficient PSCs for indoor applications.

Background: Hearing misfortune in mechanical specialist may be obliterating for the labourers, with destitute quality of life. Objective: This research was conducted to discover out the degree of hearing misfortune and audiometric design of hearing misfortune in nearby mechanical specialists. Patients & Methods: This cross-sectional research was conducted at Mayo Hospital, Lahore (January to November 2018). A add up to of 100 people were included in this research who were mechanical labourers for more than 15 a long time and came to the hospital for a few reasons other than hearing misfortune or any ENT issue. The information entered and analyzed by utilizing SPSS. Results: Majority of the subjects were male (96%) and 4% were females. Out of 18 patients were underneath the age of 35 a long time, 29 were between 36-45, 32 were between 46-55 a long time and 21 were over the age of 55 a long time. Out of 74% of the specialists were not utilizing any defensive gadget or strategy against boisterous apparatus commotions. Cruel hearing limit of all the subjects was over 25 dB in all frequencies tried i.e. from 250 to 8000 Hz. Cruel hearing misfortune was greatest at the recurrence of 4000 Hz. Conclusion: All of the specialists included in this research has a few degrees of hearing misfortune at least in a few frequencies (more articulated at 4000 Hz), in spite of the fact that larger part was not mindful of this hearing misfortune. Keywords: Commotion Initiated Hearing Misfortune, Word Related Dangers, Sensori-Neural Hearing Misfortune, Unadulterated Tone Audiometry.

Objective: To assess the part of Classification within the administration of Diabetic foot. Patients and Method: This research was carried out at Mayo Hospital, Lahore from July 2017 to December 2018. A add up to of 300 patients who detailed to Surgical Office with a foot ulcer or disease and analyzed to have Diabetes Mellitus were considered. Patients of both sexual orientation and age >12 age were included. Patients of conclusion organize renal malady, compromised insusceptibility or on steroid treatment were prohibited. Point by point history and clinical examination were recorded. Schedule examinations counting total blood examination, pee schedule examination, renal work tests, x-ray foot, chest x-ray, ECG and discharge for culture and affectability were recorded. Injuries were classified concurring to Colleges of Lahore classification and treated in like manner. Results: The larger part of the patients were of 50 to 70 age bunch. Male to female proportion was 4:1. Enormous toe was the commonest location taken after by forefoot and heel. Patients were classified as agreeing to UT classification. Patients were overseen with anti-microbial, dressings, entry point and seepage, debridement, vacuum helped closure (VAC) with or without skin joining and removals of distinctive sorts. Staphylococcus Aureus was the commonest confine. Conclusion: Our research has appeared that UT classification is a successful framework of surveying the seriousness of Diabetic foot at the time of introduction and arranging its administration. Removal rates, time of recuperating and dreariness increments with expanding arrange and review. Keywords: Diabetic foot, Diabetic ulcer, UT classification.