XIS: A Low-current, High-voltage Back-junction Back-contact Device

AbstractIn this paper we present experimental results of a low-current, high-voltage back-junction back-contact device. The concept is demonstrated by the successful transformation of finished IBC cells into XIS (Crystalline Silicon Interconnected Strips) devices, leading to 8.5V for a series connection of 14 strip cells. Different grooving methods for cell separation were evaluated regarding the effect on the quality of the groove surface. The effect of the groove passivation, which is regarded as a critical parameter to obtain high-efficiency XIS devices, was simulated to gain a better understanding of the processing requirements

Treatment with insulin (analogues) and breast cancer risk in diabetics; a systematic review and meta-analysis of in vitro, animal and human evidence

INTRODUCTION: Several studies have suggested that anti-diabetic insulin analogue treatment might increase cancer risk. The aim of this study was to review the postulated association between insulin and insulin analogue treatment and breast cancer development, and plausible mechanisms. METHOD: A systematic literature search was performed on breast cell-line, animal and human studies using the key words 'insulin analogue' and 'breast neoplasia' in MEDLINE at PubMed, EMBASE, and ISI Web of Science databases. A quantitative and qualitative review was performed on the epidemiological data; due to a limited number of reported estimates, a meta-analysis was performed for glargine only. A comprehensive overview was composed for in vitro and animal studies. Protein and gene expression was analysed for the cell lines most frequently used in the included in vitro studies. RESULTS: In total 16 in vitro, 5 animal, 2 in vivo human and 29 epidemiological papers were included. Insulin AspB10 showed mitogenic properties in vitro and in animal studies. Glargine was the only clinically available insulin analogue for which an increased proliferative potential was found in breast cancer cell lines. However, the pooled analysis of 13 epidemiological studies did not show evidence for an association between insulin glargine treatment and an increased breast cancer risk (HR 1.04; 95 % CI 0.91-1.17; p=0.49) versus no glargine in patients with diabetes mellitus. It has to be taken into account that the number of animal studies was limited, and epidemiological studies were underpowered and suffered from methodological limitations. CONCLUSION: There is no compelling evidence that any clinically available insulin analogue (Aspart, Determir, Glargine, Glulisine or Lispro), nor human insulin increases breast cancer risk. Overall, the data suggests that insulin treatment is not involved in breast tumour initiation, but might induce breast tumour progression by up regulating mitogenic signalling pathways

Has the Rate of CD4 Cell Count Decline before Initiation of Antiretroviral Therapy Changed over the Course of the Dutch HIV Epidemic among MSM?

Introduction:Studies suggest that the HIV-1 epidemic in the Netherlands may have become more virulent, leading to faster disease progression if untreated. Analysis of CD4 cell count decline before antiretroviral therapy (ART) initiation, a surrogate marker for disease progression, may be hampered by informative censoring as ART initiation is more likely with a steeper CD4 cell count decline.Methods:Development of CD4 cell count from 9 to 48 months after seroconversion was analyzed using a mixed-effects model and 2 models that jointly modeled CD4 cell counts and time to censoring event (start ART

Molecular dynamics study of isobaric and isochoric glass transitions in a model amorphous polymer

We perform molecular dynamics simulations of the glass transition through isobaric and isochoric cooling of a model polymeric material. In general, excellent agreement between the simulation results and the existing experimental trends is observed. The glass transition temperature (Tg)(Tg) is found to be a function of pressure under isobaric conditions and specific volume under isochoric conditions. Under both isobaric and isochoric conditions, the trans-state fraction and the torsional contributions to the energy undergo abrupt changes at the glass transition temperature. We analyze these data to show that the glass transition is primarily associated with the freezing of the torsional degrees of the polymer chains which is strongly coupled to the degree of freedom associated with the nonbonded Lennard-Jones potential. We attribute the greater strength of the glass transition under constant pressure conditions to the fact that the nonbonded Lennard-Jones potential is sensitive to the specific volume, which does not change during cooling under isochoric conditions. Comparison of the isochoric and isobaric data demonstrate that the thermodynamic state is independent of cooling path above Tg,Tg, while path-dependent below Tg.Tg. The simulation data show that the free volume at the isobaric glass transition temperature is pressure dependent. We also find that a glass transition occurs under isochoric conditions, even though the free volume actually increases with decreasing temperature. © 1999 American Institute of Physics

ORDERING IN CuNiZn ALLOYS

Par microscopie électronique et en mesurant la variation de résistivité les auteurs ont étudié quatre alliages de structure c.f.c., de composition Cu2NiZn, Cu3Zn, Ni3Zn et CuNi2Zn. La cinétique de grossissement isotherme de domaines ordonnés dans Cu2NiZn suit une loi [MATH] = Ktn avec n voisin de 0,3. Il n'existe pas d'ordre à grande distance dans les alliages Cu3Zn et Ni3Zn même après de longs recuits de mise en ordre aux températures de 61 et 110°C respectivement. Les micrographies en champ sombre fondamental de l'alliage CuNi2Zn présentent un fort "clustering".Electron microscopy and electrical resistivity have been used in a comparative study of Cu2NiZn, Cu3Zn, Ni3Zn and CuNi2Zn. Quantitative measurements on the kinetics of domain growth in ordered Cu2NiZn have been made and a t1'3 law is observed for the growth process. Alloys near the composition Cu3Zn and Ni3Zn do not show long range order even after long anneals at 61 and 110°C respectively. Dark field micrographs of CuNi2Zn using a fundamental reflection indicate strong clustering

Relationship between lung function and Modified Shuttle Test performance in adult patients with cystic fibrosis : A cross-sectional, retrospective study

Objectives: To investigate the relationship between lung function and exercise capacity in adults with cystic fibrosis (CF), and to develop a CF-specific equation to predict Modified Shuttle Test (MST) performance from baseline data. Design: Cross-sectional, retrospective study. Setting: Adult CF centre. Participants: One hundred and twenty-seven patients with CF [61 male; mean age 25 years (range 17 to 52 years), mean forced expiratory volume in 1 second (FEV1) 56% predicted (range 15 to 124%)]. Main outcome measures: MST and FEV1. Results: Overall, a moderate-to-good relationship was found between lung function and MST performance (walking distance vs FEV1% predicted: r = 0.64, P = 0.01). This relationship between FEV1 and MST shows an obvious threshold at an FEV1 of 67% predicted. Above this threshold, no significant association was observed between FEV1 and MST performance. However, a strong relationship (MST vs FEV1% predicted: r ≥ 0.74, P <0.01 for men and r = 0.79, P <0.01 for women) was found below an FEV1 of 67% predicted. Conclusions: This study suggests that a strong association exists between lung function (FEV1% predicted) and MST (walking distance) in adult patients with moderate-to-severe CF (FEV1 <67% predicted). A reference equation for MST performance was developed for those patients with FEV1 ≤67% predicted, providing a tool to make an a-priori prediction of MST walking distance

Amanita phalloides, a potentially lethal mushroom: Its clinical presentation and therapeutic options

Mushroom poisoning with Amanita phalloides, a rare phenonemon in everyday clinical practice in the Netherlands, must be recognized early in view of its potential morbidity and mortality. In this article 2 cases of Amanita intoxication are presented and the pharmacological basis and clinical manifestations discussed. Furthermore, the rationale of various treatment modalities, including the role of liver transplantation, is outlined