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In order to increase the photocurrent of tandem solar cells with a silicon (Si) solar cell as the bottom cell, we investigate the relationship between the localized surface plasmon resonance effect of gold nanoparticles (AuNPs) and the arrangement of AuNPs onto solar cells. AuNPs were deposited on P-type crystalline Si (c-Si) cells and Si heterojunction (SHJ) type cells. To obtain the localized surface plasmon resonance effect, the shape, size, and arrangement of the nanostructures are important. Especially, arrangement of AuNPs onto solar cells was inquired in this study because these parameters must be adjusted appropriately to produce a plasmon resonance in a specific wavelength range. It was found that the plasmon resonance effect is significant when deposited on the surface of c-Si cell rather than on top of the Ag electrode. AuNPs deposition on the c-Si cell surface leads to not only the localized surface plasmon resonance effect but also improvement in charge transport between the c-Si cell surface and Ag electrode. However, in the SHJ-type cells, the plasmon resonance effect was not observed because the surface layer was composed of a W-doped In2O3 (IWO) layer. [ABSTRACT FROM AUTHOR]

This paper particularly explains potential-induced degradation (PID) of wafer-based standard p-type crystalline silicon technology. We present a single-encapsulation method that is useful for simulating PID in the laboratory to facilitate microanalyses of module-level solar cells. The PID testing is performed for the module with single-encapsulation and conventional modules. Their current–voltage characteristics and electroluminescence images are investigated before and after the PID tests. As described herein, we infer that the single-encapsulation modules generate PID almost in the same way as conventional modules do, and that the degradation trend is almost identical to that of conventional modules. Results of PID recovery tests indicate that the time necessary for PID recovery is always less than that for PID generation, irrespective of the encapsulation method. [ABSTRACT FROM AUTHOR]

Background: In the literature, factors associated with postoperative venous thromboembolisms (VTEs) after anterior cruciate ligament reconstruction (ACLR) are limited. This study aimed to investigate the incidence of venous thromboembolisms (VTEs) after anterior cruciate ligament reconstruction (ACLR) and to identify risk and predictive factors for VTEs. Methods: This retrospective study included 136 patients who underwent arthroscopic ACLR with mechanical prophylaxis between April 2012 and July 2022. Contrast-enhanced computed tomography (CT) was applied to detect VTEs comprising deep venous thromboses and pulmonary embolisms 7 days after surgery. Data including age, sex, body mass index, concomitant treatments, graft types, smoking status, operative and tourniquet times, postoperative D-dimer levels, and other laboratory test results, were collected for analyses. The incidence of radiographically confirmed VTEs and the associated risk factors, such as age, sex, body mass index, concomitant treatments, graft types, smoking status, operative and tourniquet times, postoperative D-dimer levels, and other laboratory test results, were analyzed. Results: The overall incidence of radiographic VTEs was 11.0% (15 cases) in 136 patients. There was one symptomatic patient who had Homan's sign. Multivariable analysis indicated that postoperative D-dimer level was an independent factor related to a radiographic VTE after ACLR, although there was no association between radiographic VTEs and preoperative status or operation status. The optimal cutoff value for postoperative D-dimer level was 2.8 μg/ml according to the receiver operating characteristic curve analysis, with a sensitivity of 80.0% and specificity of 83.5%. Conclusion: The incidence of ACLR-associated radiographical VTEs (deep venous thrombosis and pulmonary embolism) under mechanical prophylaxis was 11.0% in this study. An elevated D-dimer level at 7 days after surgery is an independent predictor of VTE in patients undergoing ACLR. The postoperative D-dimer level is a more reliable marker for identifying VTE in patients who underwent ACLR. [ABSTRACT FROM AUTHOR]

This study investigated how the SiNx refractive index (RI) and SiO2 thickness, dox, of stacked SiNx/SiO2 passivation layers of the front p+emitters of n‐type crystalline‐silicon (c‐Si) photovoltaic (PV) cells affect their polarization‐type potential‐induced degradation (PID) behaviors. We prepared six n‐type c‐Si PV cells with an RI of 2.0 or 2.2 and with dox of 9, 2, or 1 nm. Then PV modules fabricated from the cells were subjected to PID tests during which a bias of −1000 V was applied to cells with respect to the front cover glass surface. For dox of 9 or 2 nm, rapid polarization‐type PID was observed, irrespective of the RI. However, for dox of 1 nm, the RI markedly affected the degradation behavior, and cells with an RI of 2.2 showed no degradation. These findings are attributable to carrier transport between the high RI (Si‐rich) SiNx and the c‐Si substrates, which can readily occur only when the SiO2 layer is sufficiently thin for electrons to tunnel through the SiO2 layer. These results are important for elucidating polarization‐type PID mechanisms and for developing preventive measures against polarization‐type PID. [ABSTRACT FROM AUTHOR]

We investigate the effect of temperature and pre-annealing on the potential-induced degradation (PID) of silicon heterojunction (SHJ) photovoltaic (PV) modules. SHJ PV modules show a faster decrease in short-circuit current density (J sc) at higher temperatures during PID tests. We also observe a complex relationship between the degree of the J sc decrease and temperature during the PID tests. Pre-annealing before the PID tests at sufficiently high temperatures leads to the complete suppression of the PID of SHJ PV modules. The decrease in J sc is known to be due to the chemical reduction of indium (In) in transparent conductive oxide (TCO) films in SHJ cells, in which water (H2O) in SHJ modules is involved. These indicate that H2O may out-diffuse from the SHJ PV modules during a PID test or pre-annealing at sufficiently high temperatures, by which the chemical reduction of indium in TCO to metallic In is suppressed. [ABSTRACT FROM AUTHOR]

An optical pH sensor that enables the non-destructive measurement of acetic acid and its distribution in a photovoltaic module during damp heat (DH) testing is reported. The sensor was fabricated by impregnating a solution of a pH-sensitive fluorescent dye into a fluororesin membrane filter, which was then dried. While conducting the DH test, fluorescence spectra from 20 pH sensors were periodically recorded and converted into pH values using a predetermined calibration curve. As a result, we succeeded in measuring changes in pH with a DH test time of up to 2000 h, and it was possible to obtain information on the pH distribution in the module. We also confirmed no change in pH in a module with a silicone encapsulant free from acetic acid, and revealed that the sensor that we developed does not respond to moisture and heat, but only to acetic acid. [ABSTRACT FROM AUTHOR]

n‐Type crystalline‐silicon (c‐Si) photovoltaic (PV) cell modules attract attention because of their potential for achieving high efficiencies. The market share of n‐type c‐Si PV modules is expected to increase considerably, with wide use in PV systems, including large‐scale PV systems, for which the system bias is set as markedly high. Such a high system bias leads to performance losses known as potential‐induced degradation (PID). By virtue of many researchers' efforts, the PID behaviors, mechanisms, and preventive measures against PID have been well documented in conventional p‐type c‐Si modules. Researchers recently started to investigate PID in high‐efficiency c‐Si solar cells including n‐type c‐Si PV modules. Yet, the understanding of PID phenomena remains incomplete. Herein, a literature review of PID in high‐efficiency n‐type c‐Si PV modules is provided as a resource elucidating the current status of related research and remaining unresolved issues. This report mainly presents discussion of PID in several kinds of n‐type c‐Si PV modules in terms of materials science. PID phenomena are described as divided into some degradation modes. Details present a review of their respective degradation modes, degradation behaviors, proposed mechanisms, and potential measures against degradation. Remaining open issues and anticipated future studies are also summarized. [ABSTRACT FROM AUTHOR]

A hexagonal boron nitride thin film was prepared on a c-plane sapphire substrate at a substrate temperature of 1200 °C and a reactor pressure of 5 kPa by chemical vapor deposition using BCl3 as a boron source. The film, consisting of columnar grains with flat top surfaces, grew epitaxially on the substrate. This sample showed pronounced intrinsic exciton cathodoluminescence (CL) at 215 nm at room temperature, although broad emission at around 350 nm was dominant. Note that the spectrum shape in the band edge region closely matched that observed for a high-quality bulk crystal in terms of peak wavelength and width. The CL images of the surface revealed the correlation between the film structure and the luminescence property, where the intrinsic excitonic luminescence was exhibited only from the columnar grains, whereas the impurity- and/or the defect-related emissions were observed mainly from surface defects with randomly oriented grains. [ABSTRACT FROM AUTHOR]

We investigate the potential-induced degradation (PID) of n-type interdigitated back-contact (IBC) crystalline Si (c-Si) photovoltaic (PV) modules under a negative bias stress and the influence of light illumination on the PID. IBC PV modules show PID characterized by a reduction in the short-circuit current density (Jsc) and open-circuit voltage (Voc) under negative bias stress, while no fill factor (FF) reduction is observed. The degradation may originate from the introduction of sodium (Na) into c-Si and the resulting enhancement of carrier recombination on the surfaces of the IBC cells. Light illumination of 1 sun during the negative bias PID test results in less severe reductions of Jsc and Voc. A reduction in the electric field on the surface Si nitride (SiNx) film, due to carrier generation in the SiNx and the resulting increase in its conductivity, is a possible explanation for the mitigation of the Na-related PID. [ABSTRACT FROM AUTHOR]

Polarization‐type potential‐induced degradation (PID‐p) of photovoltaic (PV) modules composed of n‐type interdigitated back contact (IBC) solar cells can decrease the performance of the PV modules under positive potential conditions. The purpose of this study is to observe and describe the reduction and stabilization of the electrical performance of every PV module installed in an operating PV system with the progress of the PID‐p over a time duration of 6 years. The direct current circuit of the investigated PV system is not grounded. Therefore, all the PV strings are under floating potential conditions. The results show that the performance of the n‐type IBC PV modules exhibits a two‐step degradation. In the first step of degradation, the PV performance at positive potential decreases with increasing the PV module potential, whereas the PV modules at negative potential show little performance degradation. The PV performance reduction due to PID‐p is mainly caused by the decreases in both open‐circuit voltage (VOC) and short circuit current (ISC). A PV performance reduction, which principally arises from the decrease in ISC, is observed at every PV module in the PV strings regardless of the PV module potential in the second step of degradation. Therefore, solar cell manufacturers who produce n‐type IBC, as well as those producing passivated emitters and rear totally diffused solar cells, are advised that processes to prevent the PID‐p are required. [ABSTRACT FROM AUTHOR]

We investigate the effect of silicon nitride (SiNx) films in n-type front-emitter (n-FE) crystalline Si (c-Si) solar cells on the potential-induced degradation (PID) of n-FE photovoltaic (PV) modules. A negative-bias PID test for a few min does not degrade the performance of PV modules with n-FE cells without SiNx/Si dioxide (SiO2) stacks, unlike in the case of PV modules with cells with SiNx/SiO2. This is because of the absence of polarization-type PID. After a longer PID test, the PV modules with n-FE cells without SiNx/SiO2 show a slower decrease in fill factor (FF), originating from Na introduction into the depletion layer of a p–n junction, than the modules with cells with SiNx/SiO2. The mitigation of PID by eliminating SiNx is partly consistent with the results of PV modules with p-type conventional cells without SiNx in which no PID occurs. SiNx thus has a function of enhancing Na introduction into c-Si. [ABSTRACT FROM AUTHOR]

The influences of both high-voltage stress and hygrothermal stress were studied for homojunction and heterojunction crystalline Si photovoltaic (PV) modules. In order to separately access the influence of these stresses, these PV modules were subjected to sequential tests with hygrothermal stress and high-voltage stress for various stress durations of each test. It was found that for p-type homojunction crystalline Si PV modules hygrothermal stress applied in advance considerably enhances potential-induced degradation (PID) by high-voltage stress. High-voltage stress applied in advance also accelerates finger-electrode degradation by hygrothermal stress. It was also clarified that hygrothermal stress for short duration applied in advance considerably enhances PID by high-voltage stress for n-type heterojunction crystalline Si PV modules. The possible mechanisms for these accelerated degradation phenomena by the combined stresses are presented. [ABSTRACT FROM AUTHOR]

Carrier distributions in monocrystalline silicon solar cells affected by potential-induced degradation (PID) were investigated using scanning nonlinear dielectric microscopy (SNDM), employing three samples with different PID levels. These observations clearly demonstrated that reductions in the carrier density were correlated with the extent of PID. Depth profile measurements showed that the solar cells were affected by PID to a significant depth of approximately 90 μm, equal to almost half the cell thickness. This result suggests that the Na+ migration is readily induced by the application of a high voltage. Super-higher-order-SNDM was also employed to obtain a more precise analysis of the depletion layer distributions in monocrystalline silicon solar cells with and without the application of a high voltage. The data showed that the depletion layer of a sample without PID was thinner than that of a sample exhibiting PID, indicating that the carrier concentration in the former sample was higher. This finding was in good agreement with the results produced by direct quantitative dopant measurements using SNDM. [ABSTRACT FROM AUTHOR]

Herein, the potential-induced degradation (PID) phenomenon, which can be attributed to charge-accumulation in Si photovoltaic cells, is investigated. This is achieved by performing temperature dependence measurements of the characteristic values of an n-type mono-crystalline Si photovoltaic cell, after being subjected to PID stress. The results indicate that after 7 h of PID stress, the open-circuit voltage Voc, short-circuit current density, maximum power density Pmax, and fill factor (FF) decrease by approximately 5%, 11%, 16%, and 0.7%, respectively, and eventually stabilize. The temperature coefficient (TC) of Pmax decreases from −0.413% °C−1 to −0.471% °C−1 after 7 h of PID stress and then stabilizes. These results can be explained by the fact that the charge-accumulation-type PID stress does not affect the p–n junction. It only affects the passivation layer of the cells. Thus, before and after the PID stress, the TC of Pmax is mainly determined by the TC of Voc and FF. [ABSTRACT FROM AUTHOR]

Advanced driver-assistance systems (ADASs) that provide machine support to avoid critical accidents are already in wide use in vehicles in today’s market. SoCs for such systems have several requirements: 1) high computational performance to run several advanced algorithms at low latency; 2) low power consumption to permit running under the extreme heat and power conditions of real-world vehicles; and 3) high reliability to reduce the risk of serious accidents caused by faults. This article presents a novel SoC for ADAS applications, which resolves these difficult challenges. To achieve high performance with low power consumption, the SoC adopts the heterogeneous architecture, with ten processors, four DSPs, and eight types of accelerators, including the DNN accelerator and the image signal processor (ISP). To achieve higher reliability, the SoC implements several safety mechanisms, including system partitioning to prevent fault propagation, diagnostic features to detect faults, and a dedicated controller to operate runtime built-in self-test (BIST) of the ISP’s diagnostic features during the vertical blanking interval (VBLANK). The SoC is implemented in a 16-nm process, and its size is 94.52 mm2. Peak performance of 20.5 TOPS and low power consumption of 9.78 W are achieved. [ABSTRACT FROM AUTHOR]

We have studied minority-carrier recombination lifetime in small spherical Si (<1 mm in diameter) using microwave photoconductance decay (μPCD). It was tested that 0.01 molar quinhydrone in methanol solution has the best passivation effect, which results in perfect exponential photoconductance decay curve and the highest average lifetime. However, the average lifetime of single crystalline spheres that were formed by polishing single crystalline Czochralski bulks was only 4.8 μs, and that of tear-drop-like spheres that were formed by a dropping method was 2.6 μs. These values are significantly lower compared with crystalline Si wafers. It has been found that the low lifetime is induced by the small size, and the spherical geometry does not have influence on the lifetime value. The surface recombination velocity becomes more dominant compared to bulk recombination as the size of sphere becomes smaller. Therefore, the principal of surface equivalent lifetime in the sphere is essentially different from the case of the planar wafer. [ABSTRACT FROM AUTHOR]

Spherical silicon (Si) with a size of ∼1 mm diameter was fabricated by the dropping method for the applications of spherical Si solar cells. In this research work, we characterized spherical Si by means of photoluminescence (PL) measurement at 4 and 18 K. The horn-type spherical Si crystals, formed under large undercooled conditions without a seeding technique, showed D-band luminescence originating from dislocations, whereas intrinsic PL bands of Si were not observed. In contrast, for the tear-type spherical Si crystals, formed under shadow undercooling by a seeding technique with Si powder, the boron (B) bound and Si intrinsic phonon-assisted PL bands were clearly observed both at 4 and 18 K. Moreover, the intensity ratio of B bound exciton band to Si intrinsic phonon-assisted PL band showed good correlation to the minority carrier lifetime measured with microwave photoconductance decay method. These experimental results suggested that the crystallinity of the tear-type spherical Si is significantly improved by the seeding technique compared with the horn-type ones, which contain a large amount of B-related defects. [ABSTRACT FROM AUTHOR]

Silicon spheres with a size distribution around 1.0 mm diameter, which are applicable to spherical solar cells, were formed by dropping molten silicon through a nozzle in a free-fall tube, namely, the drop method. Here we show a seeding technique for the formation of silicon spheres. In this technique, pure silicon powders with a size distribution of 1-75 μm were ejected to the molten silicon droplets at a selected part of the free-fall tube using argon carrier gas. It was considered that the attached silicon powders on the droplets worked as nuclei and stimulated the solidification to occur at low undercooling from one place. Characterizations with scanning electron microscope, carrier lifetime, and photoluminescence measurements demonstrated that the crystallinity of silicon spheres were significant improved by the seeding method. The undercooling of molten silicon droplets at solidification was speculated to decrease from ∼250 °C to below 50 °C by seeding power ejection. This resulted in an increase of average minority carrier lifetime from <0.1 μs to >1.0 μs. [ABSTRACT FROM AUTHOR]

The absolute densities of H atoms produced in catalytic chemical vapor deposition (Cat-CVD or hot-wire CVD) processes were determined by employing two-photon laser-induced fluorescence and vacuum ultraviolet absorption techniques. The H-atom density in the gas phase increases exponentially with increases in the catalyzer temperature in the presence of pure H[sub 2]. When the catalyzer temperature was 2200 K, the absolute density in the presence of 5.6 Pa of H[sub 2] (150 sccm in flow rate) was as high as 1.5×10[sup 14] cm[sup -3] at a point 10 cm from the catalyzer. This density is one or two orders of magnitude higher than those observed in typical plasma-enhanced chemical vapor-deposition processes. The H-atom density decreases sharply with the addition of SiH[sub 4]. When 0.1 Pa of SiH[sub 4] was added, the steady-state density decreased to 7×10[sup 12] cm[sup -3]. This sharp decrease can primarily be ascribed to the loss processes on chamber walls. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Studies the identification of atoms in catalytic chemical vapor deposition by laser induced fluorescence spectroscopy. Detection of ground state silicon atoms at low pressures; Electronic temperature of silicon atoms just after the formation on the catalyzer; Absolute density of silicon atoms.

Presents information on a study which examined the preparation of fluorinated amorphous carbon thin films with various fluorine concentrations using magnetron sputtering with hydrogen gas dilution into carbon tetrafluoride gas. Experimental details; Results and discussion; Conclusions.

Studies the anisotropic electrical conduction and reduction in dangling-bond density for polycrystalline silicon (poly-Si) thin films using catalytic chemical vapor deposition. Potential of poly-Si for large-are thin film electronic devices; Preparation of the silicon films; Characterization methods for Si films.

Osteoporosis patients with chronic kidney disease (CKD) are becoming common in our superaging society. Renal dysfunction causes phosphorus accumulation in the circulating plasma and leads to the development of CKD-mineral bone disorder (MBD). We have previously reported that type III Pi transporter-overexpressing transgenic (Pit-1 TG) rats manifest phosphate (Pi)-dependent podocyte injury. In the present study, we explored the effect of risedronate on Pi-induced podocyte injury in vivo. Pit-1 TG rats and wild-type rats at 5 weeks old were divided into a risedronate-treated group and an untreated group. We subcutaneously administered 5 μg/kg body weight of risedronate or saline twice a week during the experimental period. Risedronate did not alter serum creatinine levels at 5, 8, and 12 weeks of age. However, electron microscopy images showed that thickening of the glomerular basement membrane was improved in the risedronate treatment group. Furthermore, immunostaining for podocyte injury markers revealed that both desmin- and connexin43-positive areas were smaller in the risedronate-treated group than in the untreated group, suggesting that bisphosphonates could rescue Pi-induced podocyte injury. In conclusion, our findings suggest that risedronate could maintain glomerular barrier function by rescuing Pi-induced podocyte injury. [ABSTRACT FROM AUTHOR]

This paper presented whether Na ion in the front cover glass is absolute root cause of potential-induced degradation (PID) for p-type crystalline Si photovoltaic (PV) modules or not. P-type monocrystalline Si PV modules with and without the front cover glass, and with and without intentional Na contamination were subjected to PID test. Even without the front cover glass, a decrease in shunt resistance which is a characteristic feature of PID for p-type crystalline Si PV modules has been observed. Intentional Na incorporation on the cell or encapsulant also brings about remarkable PID. These results indicated that Na ion in the front cover glass is not a necessary condition for PID. Furthermore, PID occurs regardless of origin of Na ions. Relationship between PID and leakage current will be also discussed. [ABSTRACT FROM AUTHOR]

Electrical, optical, and structural properties of nitrogen-doped hydrogenated amorphous silicon films with the N content up to about 12 at. % are systematically studied using electrical conductivity measurements, electron-spin resonance, light-induced electron-spin resonance, constant photocurrent method, optical absorption spectrophotometry, IR absorption spectroscopy, Raman scattering spectroscopy, and x-ray photoelectron spectroscopy. Both behaviors of the dark conductivity and the charged-dangling-bond density against the N content suggest that most of charged dangling bonds originate from potential fluctuations. Only part of charged dangling bonds created by the N doping up to 2 at. % originate from positively charged fourfold-coordinated N. The decay behavior of the photoconductivity after mming off the probing light also supports that most of charged dangling bonds in N-doped hydrogenated amorphous silicon do not originate from positively charged fourfold-coordinated N. A possible origin of potential fluctuations is increased fluctuations in the net electron density at Si sites accompanying structural randomness caused by the N doping. © 1997 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Chronic subdural hematoma (CSDH) with brain herniation signs is rarely seen in the emergent department. As such, there are few cumulative data to analyze such cases. In this study, we evaluated the clinical features, risk factors, and rates of completion with impending brain herniation on arrival in a cohort study. We analyzed 492 consecutive patients with CSDH between January 2010 and October 2015. First, we analyzed the clinical factors and compared them between patients with or without brain herniation signs on admission. Second, we compared clinical factors between patients with or without completion of brain herniation after operation among patients who had brain herniation signs on arrival. Eleven (2.2%) patients showed brain herniation signs on arrival, and six patients (1.2%) progressed to complete brain herniation. Patients with brain herniation signs on arrival were significantly older (P = 0.03) and more frequently hospitalized with a concomitant illness (P < 0.0001). Niveau formation (P = 0.0005) and acute-on CSDH (P = 0.0001) on computed tomography were also more frequently seen in patients with brain herniation signs. Multivariate logistic regression analysis showed that age older than 75 years (OR 2.16, P < 0.0001), niveau formation (OR 3.09, P < 0.0001), acute-on CSDH (OR 14, P < 0.0001), and admitted to another hospital (OR 52.6, P < 0.0001) were independent risk factors for having had brain herniation signs on arrival. On the other hand, having a history of head injury (P = 0.02) and disappearance of the ambient cistern (P = 0.0009) were significantly associated with completion of brain herniation. The prognosis was generally poor if the patient had presented with brain herniation signs on admission. Our results demonstrate that the diagnosis is often made late, despite hospitalization for a concomitant illness. When the elderly show mild disturbance of consciousness, physicians except neurosurgeons need to consider the possibility of CSDH regardless of a recent history of head injury. [ABSTRACT FROM AUTHOR]

Long-term reliability and durability of recently installed photovoltaic (PV) systems are currently unclear because they have so far only been operated for short periods. Here, we investigated the quality of six types of recent crystalline silicon PV modules to study the viability of PV systems as dispersed power generation systems under operating conditions connected to an electric power grid. Three indicators were used to estimate the annual degradation rates of the various crystalline silicon PV modules: energy yield, performance ratio, and indoor power. Module performance was assessed both with indoor and outdoor measurements using electric measurements taken over a 3-year period. The trends in the results of the three indicators were almost consistent with each other. Although the performance of the newly installed PV modules decreased by over 2% owing to initial light-induced degradation immediately after installation, little to no degradation was observed in all the PV modules composed of p-type solar cells over a 3-year operation period. However, the PV modules composed of n-type solar cells clearly displayed performance degradation originating from the reduction of open-circuit voltage or potential-induced degradation. The results indicate that a more continuous and detailed outdoor actual investigation is important to study the quality of new, high-efficiency solar cells, such as heterojunction, interdigitated back contact solar cells, and passivated emitter rear cells, which are set to dominate the PV markets in the future. © 2017 The Authors. Progress in Photovoltaics: Research and Applications published by John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

The dynamic assembly and disassemblyof actin filaments is essential for the formation and transport of vesicles during endocytosis. In yeast, two types of actin structures, namely cortical patches and cytoplasmic cables, play a direct role in endocytosis, but how their interaction is regulated remains unclear. Here, we show that Srv2/CAP, an evolutionarily conserved actin regulator, is required for efficient endocytosis owing to its role in the formation of the actin patches that aid initial vesicle invagination and of the actin cables that these move along. Deletion of the SRV2 gene resulted in the appearance of aberrant fragmented actin cables that frequently moved past actin patches, the sites of endocytosis. We find that the C-terminal CARP domain of Srv2p is vitally important for the proper assembly of actin patches and cables; we also demonstrate that the N-terminal helical folded domain of Srv2 is required for its localization to actin patches, specifically to the ADP-actin rich region through an interaction with cofilin. These results demonstrate the in vivo roles of Srv2p in the regulation of the actin cytoskeleton during clathrin-mediated endocytosis. [ABSTRACT FROM AUTHOR]

As creep of polymeric materials is potentially a safety concern for photovoltaic modules, the potential for module creep has become a significant topic of discussion in the development of IEC 61730 and IEC 61215. To investigate the possibility of creep, modules were constructed, using several thermoplastic encapsulant materials, into thin-film mock modules and deployed in Mesa, Arizona. The materials examined included poly(ethylene)-co-vinyl acetate (EVA, including formulations both cross-linked and with no curing agent), polyethylene/polyoctene copolymer (PO), poly(dimethylsiloxane) (PDMS), polyvinyl butyral (PVB), and thermoplastic polyurethane (TPU). The absence of creep in this experiment is attributable to several factors of which the most notable one was the unexpected cross-linking of an EVA formulation without a cross-linking agent. It was also found that some materials experienced both chain scission and cross-linking reactions, sometimes with a significant dependence on location within a module. The TPU and EVA samples were found to degrade with cross-linking reactions dominating over chain scission. In contrast, the PO materials degraded with chain scission dominating over cross-linking reactions. Although we found no significant indications that viscous creep is likely to occur in fielded modules capable of passing the qualification tests, we note that one should consider how a polymer degrades, chain scission or cross-linking, in assessing the suitability of a thermoplastic polymer in terrestrial photovoltaic applications. [ABSTRACT FROM AUTHOR]

Recently there has been increased interest in using thermoplastic encapsulant materials in photovoltaic modules, but concerns have been raised about whether these would be mechanically stable at high temperatures in the field. Recently, this has become a significant topic of discussion in the development of IEC 61730 and IEC 61215. We constructed eight pairs of crystalline-silicon modules and eight pairs of glass/encapsulation/glass thin-film mock modules using different encapsulant materials, of which only two were formulated to chemically crosslink. One module set was exposed outdoors with thermal insulation on the back side in Mesa, Arizona, in the summer (hot-dry), and an identical module set was exposed in environmental chambers. High-precision creep measurements (±20 µm) and electrical performance measurements indicate that despite many of these polymeric materials operating in the melt or rubbery state during outdoor deployment, no significant creep was seen because of their high viscosity, lower operating temperature at the edges, and/or the formation of chemical crosslinks in many of the encapsulants with age despite the absence of a crosslink-ing agent. Only an ethylene-vinyl acetate (EVA) encapsulant formulated without a peroxide crosslinking agent crept significantly. In the case of the crystalline-silicon modules, the physical restraint of the backsheet reduced creep further and was not detectable even for the EVA without peroxide. Because of the propensity of some polymeric materials to crosslink as they age, typical thermoplastic encapsulants would be unlikely to result in creep in the vast majority of installations. [ABSTRACT FROM AUTHOR]

The peptide- N-( N-acetyl-β- d-glucosaminyl) asparagine amidase F (PNGase F) catalyzes the cleavage of N-linked oligosaccharides between the innermost GlcNAc and asparagine residues of high mannose, hybrid and complex oligosaccharides from glycoproteins. The PNGase F has broad substrate specificity and thus is extensively used for the structural and functional studies of the glycoproteins. In this study, we tried to produce active recombinant PNGase F as secreted and intracellular-expressed forms using baculovirus expression vector system (BEVS) through silkworm larvae or cultured cells. PNGase F itself contains potential N-linked glycosylation sites and we found that it was N-glycosylated when PNGase F secreted from silkworm cells. Intriguingly, the secreted recombinant PNGase F has the lower catalytic activity and self-digests its N-linked glycans and therefore this secreted form of this enzyme produced from BEVS is not appropriate for carbohydrate chain analysis. Instead, we successfully mass-produced (2.1 mg/20 silkworm larvae) and purified active recombinant PNGase F as an intracellular protein without N-glycosylations. Besides, we confirmed by directed mutagenesis that several amino acid residues are crucial for the function of PNGase F. Our results provide an alternative method for the mass production of active enzymes involved in the study of glycoproteins. [ABSTRACT FROM AUTHOR]

(1) Background: Protein stimulates the secretion of glucagon (GCG), which can affect glucose metabolism. This study aimed to analyze the metabolic effect of a high-protein diet (HPD) in the presence or absence of proglucagon-derived peptides, including GCG and GLP-1. (2) Methods: The response to HPD feeding for 7 days was analyzed in mice deficient in proglucagon-derived peptides (GCGKO). (3) Results: In both control and GCGKO mice, food intake and body weight decreased with HPD and intestinal expression of Pepck increased. HPD also decreased plasma FGF21 levels, regardless of the presence of proglucagon-derived peptides. In control mice, HPD increased the hepatic expression of enzymes involved in amino acid metabolism without the elevation of plasma amino acid levels, except branched-chain amino acids. On the other hand, HPD-induced changes in the hepatic gene expression were attenuated in GCGKO mice, resulting in marked hyperaminoacidemia with lower blood glucose levels; the plasma concentration of glutamine exceeded that of glucose in HPD-fed GCGKO mice. (4) Conclusions: Increased plasma amino acid levels are a common feature in animal models with blocked GCG activity, and our results underscore that GCG plays essential roles in the homeostasis of amino acid metabolism in response to altered protein intake. [ABSTRACT FROM AUTHOR]

Endo-β- N-acetylglucosaminidase (Endo H) from Streptomyces plicatus hydrolyzes the core di-GlcNAc units of asparagine-linked oligosaccharides and is regarded as an important tool for glycobiology research. In the present study, we established a large-scale system to produce secreted Endo H using a silkworm-baculovirus expression system (silkworm-BES). The recombinant Endo H purified from silkworm hemolymph had activity comparable to that from recombinant Escherichia coli. As well as its well-characterized substrate RNase B, the Endo H from silkworm-BES was able to deglycosylate the high-mannose glycoproteins from silkworm hemolymph. Interestingly, the secretion amount of recombinant Endo H was significantly varied among the different silkworm strains, which could provide valuable information for larger-scale protein productions from silkworm-BES. [ABSTRACT FROM AUTHOR]

The double-stranded RNA (dsRNA) mediated RNA interference (RNAi) is widely employed in silkworm and its tissue-derived cell lines for gene function analysis. Baculovirus expression vector system (BEVS) has an advantage for large-scale protein expression. Previously, combining these useful tools, we improved traditional AcMNPV-Sf9 BEVS to produce modified target glycoproteins, where the ectopic expression of Caenorhabditis elegans systemic RNAi defective-1 (SID-1) was found to be valuable for soaking RNAi. In current study, we applied CeSID-1 protein to a Bombyx mori NPV (BmNPV)-hypersensitive Bme21 cell line and investigated its properties both in soaking RNAi ability and recombinant protein expression. The soaking RNAi-mediated suppression in the Bme21 cell enables us to produce modified glycoproteins of interest in BmNPV-Bme21 BEVS. [ABSTRACT FROM AUTHOR]

The double-stranded RNA (dsRNA) mediated RNA interference (RNAi) is widely employed in silkworm and its tissue-derived cell lines for gene function analysis. Baculovirus expression vector system (BEVS) has an advantage for large-scale protein expression. Previously, combining these useful tools, we improved traditional AcMNPV-Sf9 BEVS to produce modified target glycoproteins, where the ectopic expression of Caenorhabditis elegans systemic RNAi defective-1 (SID-1) was found to be valuable for soaking RNAi. In current study, we applied CeSID-1 protein to a Bombyx mori NPV (BmNPV)-hypersensitive Bme21 cell line and investigated its properties both in soaking RNAi ability and recombinant protein expression. The soaking RNAi-mediated suppression in the Bme21 cell enables us to produce modified glycoproteins of interest in BmNPV–Bme21 BEVS. [ABSTRACT FROM AUTHOR]