29 research outputs found
Characterization of silicon heterojunctions for solar cells
Conductive-probe atomic force microscopy (CP-AFM) measurements reveal the existence of a conductive channel at the interface between p-type hydrogenated amorphous silicon (a-Si:H) and n-type crystalline silicon (c-Si) as well as at the interface between n-type a-Si:H and p-type c-Si. This is in good agreement with planar conductance measurements that show a large interface conductance. It is demonstrated that these features are related to the existence of a strong inversion layer of holes at the c-Si surface of (p) a-Si:H/(n) c-Si structures, and to a strong inversion layer of electrons at the c-Si surface of (n) a-Si:H/(p) c-Si heterojunctions. These are intimately related to the band offsets, which allows us to determine these parameters with good precision
Vitamin C Enhances Vitamin E Status and Reduces Oxidative Stress Indicators in Sea Bass Larvae Fed High DHA Microdiets
Docosahexaenoic acid (DHA) is an essential fatty acid necessary for many biochemical, cellular and physiological functions in fish. However, high dietary levels of DHA increase free radical injury in sea bass (Dicentrarchus labrax) larvae muscle, even when vitamin E (α-tocopherol, α-TOH) is increased. Therefore, the inclusion of other nutrients with complementary antioxidant functions, such as vitamin C (ascorbic acid, vitC), could further contribute to prevent these lesions. The objective of the present study was to determine the effect of vitC inclusion (3,600 mg/kg) in high DHA (5 % DW) and α-TOH (3,000 mg/kg) microdiets (diets 5/3,000 and 5/3,000 + vitC) in comparison to a control diet (1 % DHA DW and 1,500 mg/kg of α-TOH; diet 1/1,500) on sea bass larvae growth, survival, whole body biochemical composition and thiobarbituric acid reactive substances (TBARS) content, muscle morphology, skeletal deformities and antioxidant enzymes, insulin-like growth factors (IGFs) and myosin expression (MyHC). Larvae fed diet 1/1,500 showed the best performance in terms of total length, incidence of muscular lesions and ossification degree. IGFs gene expression was elevated in 5/3,000 diet larvae, suggesting an increased muscle mitogenesis that was confirmed by the increase in the mRNA copies of MyHC. vitC effectively controlled oxidative damages in muscle, increased α-TOH larval contents and reduced TBARS content and the occurrence of skull deformities. The results of the present study showed the antioxidant synergism between vitamins E and C when high contents of DHA are included in sea bass larvae diets
Harms titanium mesh cage fracture
Interbody fusion has become a mainstay of surgical management for lumbar fractures, tumors, spondylosis, spondylolisthesis and deformities. Over the years, it has undergone a number of metamorphoses, as novel instrumentation and approaches have arisen to reduce complications and enhance outcomes. Interbody fusion procedures are common and successful, complications are rare and most often do not involve the interbody device itself. We present here a patient who underwent an anterior L4 corpectomy with Harms cage placement and who later developed a fracture of the lumbar titanium mesh cage (TMC). This report details the presentation and management of this rare complication, as well as discusses the biomechanics underlying this rare instrumentation failure