TCO Optimization in Si Heterojunction Solar Cells on p-type Wafers with n-SiOx Emitter☆

Abstract Silicon heterojunction solar cells have largely demonstrated their suitability to reach high efficiencies. We have here focused on p-type c-Si wafers as absorber, considering that they share more than 90% of the solar cell market. To overcome some of the issues encountered in the conventional (n)a-Si:H/(p)c-Si configuration, we have implemented a mixed phase n-type silicon oxide (n-SiOx) emitter in order to gain from the wider bandgap and lower activation energy of this material with respect to (n)a-Si:H. The workfunction of the transparent conductive oxide layer (WTCO) plays also a key role, as it may induce an unfavourable band bending at the interface with the emitter. We have here focused on AZO, a promising alternative to ITO. Different layers with varying WTCO were prepared, by changing relevant deposition parameters, and were tested into solar cells. The experimental results have been explained with the aid of numerical simulations. Finally, for the n-SiOx/(p)c-Si heterojunction with optimized WTCO a potential conversion efficiency well over 23% has been estimated

Effects of Probiotics on Colitis-Induced Exacerbation of Alzheimer\u27s Disease in

Alzheimer’s disease (AD) is characterized by progressive cognitive decline and is a leading cause of death in the United States. Neuroinflammation has been implicated in the progression of AD, and several recent studies suggest that peripheral immune dysfunction may influence the disease. Continuing evidence indicates that intestinal dysbiosis is an attribute of AD, and inflammatory bowel disease (IBD) has been shown to aggravate cognitive impairment. Previously, we separately demonstrated that an IBD-like condition exacerbates AD-related changes in the brains of the AppNL-G-F mouse model of AD, while probiotic intervention has an attenuating effect. In this study, we investigated the combination of a dietary probiotic and an IBD-like condition for effects on the brains of mice. Male C57BL/6 wild type (WT) and AppNL-G-F mice were randomly divided into four groups: vehicle control, oral probiotic, dextran sulfate sodium (DSS), and DSS given with probiotics. As anticipated, probiotic treatment attenuated the DSS-induced colitis disease activity index in WT and AppNL-G-F mice. Although probiotic feeding significantly attenuated the DSS-mediated increase in WT colonic lipocalin levels, it was less protective in the AppNL-G-F DSS-treated group. In parallel with the intestinal changes, combined probiotic and DSS treatment increased microglial, neutrophil elastase, and 5hmC immunoreactivity while decreasing c-Fos staining compared to DSS treatment alone in the brains of WT mice. Although less abundant, probiotic combined with DSS treatment demonstrated a few similar changes in AppNL-G-F brains with increased microglial and decreased c-Fos immunoreactivity in addition to a slight increase in Aβ plaque staining. Both probiotic and DSS treatment also altered the levels of several cytokines in WT and AppNL-G-F brains, with a unique increase in the levels of TNFα and IL-2 being observed in only AppNL-G-F mice following combined DSS and probiotic treatment. Our data indicate that, while dietary probiotic intervention provides protection against the colitis-like condition, it also influences numerous glial, cytokine, and neuronal changes in the brain that may regulate brain function and the progression of AD

Nonclostridial anaerobic infections to patients with severe comorbidities

Catedra Chirurgie nr.1 ,,Nicolae Anestiadi”, Universitatea de Stat de Medicină și Farmacie ”Nicolae Testemitanu”, Spitalul ”Sf. Arhanghel Mihail”, Chișinau, Republica Moldova, Al XIII-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” și al III-lea Congres al Societății de Endoscopie, Chirurgie miniminvazivă și Ultrasonografie ”V.M.Guțu” din Republica MoldovaIntroducere: Infecția necrotico-gangrenoasă expansivă continuă să fie o problemă severă chirurgicală prin tratamentul dificil și mortalitate înaltă. Material și metode: Studiul vizează 60 pacienți cu afectarea țesuturilor moi tratați în perioada 2006-2016. Repartiție pe sex: barbați-22, femei-38, cu vârsta cuprinsă între 26 și 71 ani. Durata medie de tratament a constituit 14.9 zile. Morfologic s-au stabilit: fasceite (13), flegmoane (26), gangrene gazoase (5), pantisulite (7), abcese (9). În structura comorbidităților a predominat diabetul zaharat. Flora patogenă combinată a fost stabilită în 30% cazuri. Antibioticoterapia a vizat atît flora aerobă cît şi flora anaerobă constituind o asociere a 2-3 preparate. Intervenţia primară a constat în debridarea largă, necrectomii până la ţesuturile viabile, urmate de debridări ulterioare sub anestezii generale. Rezultate: Vindecare completă prin suturi tardive secundare s-a efectuat la 36 pacienţi. Defecte cutanate cu plastii ulterioare la 7 pacienţi. Evoluţia postoperatorie în secţia ATI (anestezie și terapie intensivă) prin sindromul MODS (Sindrom de disfuncție multiplă de organe) instalat s-a înregistrat la 12 pacienţi, cu o durată de aflare în secţia ATI de 4,3 zile. Mortalitatea a constituit 5 cazuri (11,7%), cauza nemijlocită fiind MODS septic. Concluzii: Infecţiile necrotico–gangrenoase grave survin la pacienţii cu tare asociate, imunocompromişi, cu predominanță în diabetul zaharat, patologia cardio-vasculară, hepato-renală. Tratamentul chirurgical trebuie să includă operația primară radicală, urmată de reintervenții seriate obligatorii. Antibioticoterapia contemporană completează tratamentul chirurgical. Succesul tratamentului depinde de stabilirea precoce a diagnosticului, agresivitatea debridărilor chirurgicale și de aplicarea tratamentului complex în secția ATI. * * * Introduction: Extensive necrotic-gangrene infection continues to be a severe surgical problem due to its difficult treatment and high mortality. Materials and methods: The study covers 60 patients with soft tissues damages treated between 2006-2016. Distribution by gender: male-22, female-38, aged 26 to 71 years. The average duration of treatment was 14.9 days. Morphological findings have been established: fasciitis (13), phlegmons (26), gas gangrenes (5), pantisulitis (7), abscesses (9). Diabetes prevailed in the structure of comorbiditities. The combined pathogenic flora was established in 30% of cases. Antibiotic therapy targeted both aerobic flora and anaerobic flora, constituting an association of 2-3 medicines. Primary intervention consisted of extensive debridement, necrectomy to viable tissues, followed by subsequent debridements under general anesthesia. Results: Complete healing with secondary late sutures was performed in 36 patients. Skin defects followed by cutaneous scarring in 7 patients. The postoperative progression in the ATI (anesthesia and intensive care) department through MODS (Multiple Organ Dysfunction Syndrome) syndrome was recorded in 12 patients with a duration of 4.3 days in the ATI department. Mortality - 5 cases (11.7%), the septic MODS being the direct cause. Conclusions: Severe necrotic-gangrenic infections occur in patients with associated, immunocompromised, predominantly diabetic, cardiovascular, hepato-renal pathology. Surgical treatment should include the primary surgery, followed by compulsory repeated interventions. Contemporary antibiotic therapy completes surgical treatment. The success of treatment depends on the early diagnosis, the aggressiveness of surgical debridations, and the complex treatment in the ATI department

Characterizations of nanostructured silicon-carbon films deposited on p-layer by PECVD

Nanostructured silicon carbon films composed of silicon nanocrystallites embedded in the amorphous silicon carbon matrix are prepared by a rf-PECVD system at 250 °C from silane and methane gas mixture highly diluted in hydrogen onto 7059 Corning glass and p-layer deposited on tin oxide substrates by varying rf power from 25 to 65 W. The structural and compositional properties of the films have been investigated. The study demonstrates that rf power controls the crystalline fraction as well as the silicon crystallite size and that p-layer/tin oxide structure enhances the nucleation of silicon grains as compared to Corning glas

Characterizations of nanostructured silicon-carbon films deposited on p-layer by PECVD

Nanostructured silicon carbon films composed of silicon nanocrystallites embedded in the amorphous silicon carbon matrix are prepared by a rf-PECVD system at 250 °C from silane and methane gas mixture highly diluted in hydrogen onto 7059 Corning glass and p-layer deposited on tin oxide substrates by varying rf power from 25 to 65 W. The structural and compositional properties of the films have been investigated. The study demonstrates that rf power controls the crystalline fraction as well as the silicon crystallite size and that p-layer/tin oxide structure enhances the nucleation of silicon grains as compared to Corning glas

TCO Workfunction in N-Silicon Oxide Emitter – c-Si (P) Heterojunction Solar Cell: An Open Issue

The amorphous/crystalline silicon heterojunction solar cells have largely demonstrated to be high efficiency capable. Despite the highest efficiency cells are based on high quality n-type c-Si absorber, the p-type hold more than 90% of the world silicon solar cell market, so it seems important to improve device and cost efficiency using p-type substrates. An issue of is related to the amorphous layer absorbance so different materials have been studied and tested as replacing emitter to obtain a gain in terms of transmittance, conductivity and Jsc. We have adopted a different and wider bandgap emitter based on silicon oxide, n-SiOx. A central role in this type of structure is played from the chosen TCO workfunction, whose value affects strongly the heterojunction’s band structure at the emitter interface. RF magnetron sputtered TCO obtained with different deposition parameters, have been made in order to optimize their use in our heterojunction solar cell. Numerical simulation on the SiOx HJ, with TCO having proper workfunction value, show potential efficiency conversion well over the 23