A Comprehensive Review on Current Performance, Challenges and Progress in Thin-Film Solar Cells

Due to the recent surge in silicon demand for solar modules, thin-film photovoltaic (PV) modules have a potential to penetrate the market in significant numbers. As an alternate candidate, thin film technologies in PVs have the ability to achieve better performance. The competing thin-film PV technologies have the flexibility to adapt to any sort of curvature compared to rigid solar cells (SCs). Due to the peculiar characteristics of newer solar materials, stability issues, reflection losses, advancements in electrode materials and dopant materials with a photoactive layer are current challenges driving the industrial-academic voyage of development of solar materials for the betterment of Photo-conversion Efficiency (PCE). Based on the photoactive materials used over time, SC evolution was broadly classified into first, second and third generation SCs. In this review, the basic working mechanisms, various materials used, drawbacks and stability issues of different SCs are discussed extensively. Thin film SCs tend to absorb certain elastic deformations due to their flexible nature and to a certain extent. According to the NREL efficiency chart, multi-junctional SCs exhibit enhanced efficiency as compared to the other SCs. Among the third-generation SCs, the perovskite/Si tandem architecture shows a maximum efficiency of approximately 29%. Thin film flexible SCs find application in various sectors such as automobile, defense and/or energy storage device

Primary Closure Versus T-tube Drainage After Open Choledochotomy

Choledochotomy followed by T-tube has long been a standard surgical treatment for choledocholithiasis. It is still a preferred choice in many hospitals where minimal invasive procedures are not feasible. The use of T-tube is not without complications. To avoid the complications associated with T-tube, we have performed primary closure of the common bile duct (CBD) after exploration. This pilot study assesses the safety of primary closure of CBD, which would help form a basis for implementation on a wider scale. Objective: To compare the clinical results of primary closure with T-tube drainage after open choledochotomy and assess the safety of primary closure for future application on a greater mass. Patients and Methods: This comparative study was conducted at surgical unit IV Liaquat University of Medical and Health Sciences, Jamshoro, from January 2007 to December 2007. Thirty-five patients were included in the study of which 16 patients underwent primary closure. Results: Thirty-five patients were included in the study. The mean age of patients who had primary closure done (n = 16) was 46.0 ± 16.8 and there were two (12.5%) males and 14 (87.5%) females. After primary closure of the CBD, bile leakage was noted in one patient (6.3%), which subsided without any biliary peritonitis as compared to the T-tube group in which two patients (10.5%) had bile leakage. Postoperative jaundice was seen in one patient (5.3%) who had a T-tube because of a blockage of CBD. Not a single patient had a retained stone in both groups as well as no recurrence of CBD stones. The postoperative hospital stay after primary closure was 5.56 ± 1.1 days as compared to after T-tube drainage which was 13.6 ± 2.3 days. The total cost of treatment in patients who underwent primary closure was USD194.5 ± 41.5 but after T-tube drainage it was USD548.6 ± 88.5. The median follow up duration for both groups was 6 months. Conclusion: Primary CBD closure is a safe and cost effective alternative to routine T-tube drainage after open choledochotomy

Influence of human t-cell lymphotropic virus type 1 (HTLV-1) Infection on laboratory parameters of patients with chronic hepatitis C virus Influência da infecção pelo vírus linfotrópico humano tipo 1 (HTLV-1) em parâmetros laboratoriais de pacientes com hepatite C crônica

Hepatitis C virus (HCV) and human T-cell lymphotropic virus type 1 (HTLV-1) share routes of transmission and some individuals have dual infection. Although some studies point to a worse prognosis of hepatitis C virus in patients co-infected with HTLV-1, the interaction between these two infections is poorly understood. This study evaluated the influence of HTLV-1 infection on laboratory parameters in chronic HCV patients. Twelve HTLV-1/HCV-coinfected patients were compared to 23 patients infected only with HCV, in regard to demographic data, risk factors for viral acquisition, HCV genotype, presence of cirrhosis, T CD4+ and CD8+ cell counts and liver function tests. There was no difference in regard to age, gender, alcohol consumption, smoking habits, HCV genotype or presence of cirrhosis between the groups. Intravenous drug use was the most common risk factor among individuals co-infected with HTLV-1. These patients showed higher TCD8+ counts (p = 0.0159) and significantly lower median values of AST and ALT (p = 0.0437 and 0.0159, respectively). In conclusion, we have shown that HCV/HTLV-1 co-infected patients differs in laboratorial parameters involving both liver and immunological patterns. The meaning of these interactions in the natural history of these infections is a matter that deserves further studies.<br>O vírus da hepatite C (VHC) e vírus linfotrópico humano tipo 1 (HTLV-1) compartilham formas de transmissão e algumas pessoas apresentam coinfecção. Embora alguns estudos apontem para um pior prognóstico da infecção pelo VHC em pacientes coinfectados com HTLV-1, a interação entre estas infecções é mal compreendida. Este estudo avaliou a influência da infecção pelo HTLV-1 em parâmetros laboratoriais de pacientes com VHC. 12 coinfectados VHC/HTLV-1 foram comparados com 23 pacientes monoinfectados com VHC, no que diz respeito aos dados demográficos, fatores de risco para aquisição viral, genótipo do VHC, presença de cirrose, contagens de linfócitos T CD4+ e CD8+ e testes de função hepática. Não houve diferença em relação à idade, sexo, consumo de álcool, tabagismo, genótipo do VHC ou presença de cirrose entre os grupos. O uso de drogas injetáveis foi o fator de risco mais comum entre coinfectados. Esses pacientes apresentaram maiores contagens de linfócitos T CD8+ e valores medianos de AST e ALT significativamente mais baixos (p = 0,0437 e 0,0159, respectivamente). Em conclusão, demonstrou-se que os pacientes com VHC/HTLV-1 diferem quanto aos parâmetros hepáticos e imunológicos. O significado destas diferenças na história natural destas infecções é um assunto que merece estudos mais aprofundados

Immunocompromised patients with acute respiratory distress syndrome : Secondary analysis of the LUNG SAFE database

The aim of this study was to describe data on epidemiology, ventilatory management, and outcome of acute respiratory distress syndrome (ARDS) in immunocompromised patients. Methods: We performed a post hoc analysis on the cohort of immunocompromised patients enrolled in the Large Observational Study to Understand the Global Impact of Severe Acute Respiratory Failure (LUNG SAFE) study. The LUNG SAFE study was an international, prospective study including hypoxemic patients in 459 ICUs from 50 countries across 5 continents. Results: Of 2813 patients with ARDS, 584 (20.8%) were immunocompromised, 38.9% of whom had an unspecified cause. Pneumonia, nonpulmonary sepsis, and noncardiogenic shock were their most common risk factors for ARDS. Hospital mortality was higher in immunocompromised than in immunocompetent patients (52.4% vs 36.2%; p < 0.0001), despite similar severity of ARDS. Decisions regarding limiting life-sustaining measures were significantly more frequent in immunocompromised patients (27.1% vs 18.6%; p < 0.0001). Use of noninvasive ventilation (NIV) as first-line treatment was higher in immunocompromised patients (20.9% vs 15.9%; p = 0.0048), and immunodeficiency remained independently associated with the use of NIV after adjustment for confounders. Forty-eight percent of the patients treated with NIV were intubated, and their mortality was not different from that of the patients invasively ventilated ab initio. Conclusions: Immunosuppression is frequent in patients with ARDS, and infections are the main risk factors for ARDS in these immunocompromised patients. Their management differs from that of immunocompetent patients, particularly the greater use of NIV as first-line ventilation strategy. Compared with immunocompetent subjects, they have higher mortality regardless of ARDS severity as well as a higher frequency of limitation of life-sustaining measures. Nonetheless, nearly half of these patients survive to hospital discharge. Trial registration: ClinicalTrials.gov, NCT02010073. Registered on 12 December 2013