14 research outputs found
Ripening-associated ethylene biosynthesis in tomato fruit is autocatalytically and developmentally regulated
To investigate the regulatory mechanism(s) of ethylene biosynthesis in fruit, transgenic tomatoes with all known LeEIL genes suppressed were produced by RNA interference engineering. The transgenic tomato exhibited ethylene insensitivity phenotypes such as non-ripening and the lack of the triple response and petiole epinasty of seedlings even in the presence of exogenous ethylene. Transgenic fruit exhibited a low but consistent increase in ethylene production beyond 40 days after anthesis (DAA), with limited LeACS2 and LeACS4 expression. 1-Methylcyclopropene (1-MCP), a potent inhibitor of ethylene perception, failed to inhibit the limited increase in ethylene production and expression of the two 1-aminocyclopropane-1-carboxylic acid (ACC) synthase (ACS) genes in the transgenic fruit. These results suggest that ripening-associated ethylene (system 2) in wild-type tomato fruit consists of two parts: a small part regulated by a developmental factor through the ethylene-independent expression of LeACS2 and LeACS4 and a large part regulated by an autocatalytic system due to the ethylene-dependent expression of the same genes. The results further suggest that basal ethylene (system 1) is less likely to be involved in the transition to system 2. Even if the effect of system 1 ethylene is eliminated, fruit can show a small increase in ethylene production due to unknown developmental factors. This increase would be enough for the stimulation of autocatalytic ethylene production, leading to fruit ripening
Impact of Heterointerfaces in Solar Cells Using ZnSnP₂ Bulk Crystals
We report on the optimization of interface structure in ZnSnP₂ solar cells. The effects of back electrode materials and related interface on photovoltaic performance were investigated. It was clarified that a conventional structure Mo/ZnSnP₂ showed a Schottky-behavior, while an ohmic-behavior was observed in the Cu/ZnSnP₂ structure annealed at 300 °C. STEM-EDX analysis suggested that Cu–Sn–P ternary compound was formed at the interface. This compound is considered to play an important role to obtain the ohmic contact between ZnSnP₂ and Cu. In addition, it was clarified that the aqua regia etching of ZnSnP₂ bulk crystals before chemical bath deposition process for the preparation of buffer layer was effective to remove the layer including lattice defects introduced by mechanical-polishing, which was supported by TEM observations and photoluminescence measurements. This means that the carrier transport across the interface was improved because of the reduced defect at the interface. Consequently, the conversion efficiency of approximately 2% was achieved with the structure of Al/ZnO;Al/ZnO/CdS/ZnSnP₂/Cu, where the values of short circuit current density, JSC, open circuit voltage, VOC, and fill factor, FF, were 8.2 mA cm⁻², 0.452 V, and 0.533, respectively. However, the value of Voc was largely low considering the bandgap value of ZnSnP₂. To improve the conversion efficiency, the optimization of buffer layer material is considered to be essential in the viewpoint of band alignment
Cognitive transitions based on functional status in older adults with heart failure: a population‐based study
Abstract Aims Cognitive impairment and functional status are both important determinants of poor outcomes in heart failure (HF). However, little is known about how functional status impacts the changes in cognitive status during the disease course. This study aimed to describe the cognitive transitions in patients with HF and assess the relationship of these transitions to functional status, which was assessed by the dependency of activities of daily living (ADL). Methods and results This retrospective cohort study included 1764 patients with an International Classification of Diseases‐10 code of HF (≥65 years, mean age 82.3 ± 7.9 years, 39% male) from a long‐term care and medical insurance database from Nobeoka city, a rural city of south‐western Japan. Cognitive status at baseline and 6, 12, 18, and 24 month time points was collected, and participants were stratified based on ADL status at baseline. Generalized estimating equations and multi‐state modelling were used to examine associations between ADL dependency and cognitive changes/mortality. Transition probabilities were estimated using multi‐state modelling. At baseline, there were 1279 (73%) and 485 (27%) patients with independent and dependent ADL, respectively. In overall patients, 1656 (93.9%) patients had normal/mild cognitive status and 108 (6%) patients had a moderate/severe cognitive status at baseline. The majority [104 (96%) patients] of patients with moderate/severe cognitive status at baseline had dependent ADL. In patients with moderate/severe cognitive status, the number of patients with dependent ADL always outnumbered that of the independent ADL throughout the follow‐up. Multi‐state modelling estimated that patients with dependent ADL and normal/mild cognitive status at baseline had 47% probability of maintaining the same cognitive status at 24 months, while the probability of maintaining the same cognitive status was 86% for those with independent ADL. Patients with normal/mild cognitive status in the dependent ADL group at baseline had a higher risk of experiencing a transition to moderate/severe cognitive status at any time point during 24 months compared with those with independent ADL [hazard ratio 5.24 (95% confidence interval 3.47–7.90)]. Conclusions In older patients with HF, the prevalence of cognitive impairment was always higher for those with reduced functional status. Despite having a normal/mild cognitive status at baseline, patients with dependent ADL are at high risk of experiencing cognitive decline over 24 months with substantially less chance of maintaining their cognitive status. ADL dependency was an important risk factor of cognitive decline in patients with HF
Impact of Heterointerfaces in Solar Cells Using ZnSnP<sub>2</sub> Bulk Crystals
We report on the
optimization of interface structure in ZnSnP<sub>2</sub> solar cells.
The effects of back electrode materials and related interface on photovoltaic
performance were investigated. It was clarified that a conventional
structure Mo/ZnSnP<sub>2</sub> showed a Schottky-behavior, while an
ohmic-behavior was observed in the Cu/ZnSnP<sub>2</sub> structure
annealed at 300 °C. STEM-EDX analysis suggested that Cu–Sn–P
ternary compound was formed at the interface. This compound is considered
to play an important role to obtain the ohmic contact between ZnSnP<sub>2</sub> and Cu. In addition, it was clarified that the aqua regia
etching of ZnSnP<sub>2</sub> bulk crystals before chemical bath deposition
process for the preparation of buffer layer was effective to remove
the layer including lattice defects introduced by mechanical-polishing,
which was supported by TEM observations and photoluminescence measurements.
This means that the carrier transport across the interface was improved
because of the reduced defect at the interface. Consequently, the
conversion efficiency of approximately 2% was achieved with the structure
of Al/ZnO;Al/ZnO/CdS/ZnSnP<sub>2</sub>/Cu, where the values of short
circuit current density, <i>J</i><sub>SC</sub>, open circuit
voltage, <i>V</i><sub>OC</sub>, and fill factor, FF, were
8.2 mA cm<sup>–2</sup>, 0.452 V, and 0.533, respectively. However,
the value of <i>V</i><sub>OC</sub> was largely low considering
the bandgap value of ZnSnP<sub>2</sub>. To improve the conversion
efficiency, the optimization of buffer layer material is considered
to be essential in the viewpoint of band alignment
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Giant faraday rotation through ultra-small Fe0n clusters in superparamagnetic FeO-SiO2 vitreous films
Magnetooptical (MO) glasses and, in particular, Faraday rotators are becoming key components in lasers and optical information processing, light switching, coding, filtering, and sensing. The common design of such Faraday rotator materials follows a simple path: high Faraday rotation is achieved by maximizing the concentration of paramagnetic ion species in a given matrix material. However, this approach has reached its limits in terms of MO performance; hence, glass‐based materials can presently not be used efficiently in thin film MO applications. Here, a novel strategy which overcomes this limitation is demonstrated. Using vitreous films of xFeO·(100 − x)SiO2, unusually large Faraday rotation has been obtained, beating the performance of any other glassy material by up to two orders of magnitude. It is shown that this is due to the incorporation of small, ferromagnetic clusters of atomic iron which are generated in line during laser deposition and rapid condensation of the thin film, generating superparamagnetism. The size of these clusters underbids the present record of metallic Fe incorporation and experimental verification in glass matrices
Association between comprehensive workstation and neck and upper-limb pain among office worker
Objectives: Our study aimed to investigate the association between comprehensive workstations and neck and upper-limb pain (NUP) among office workers. Methods: This cross-sectional study included 307 office workers (median age, 39 years; 88% men). Workstations (presence of armrest, armrest position, number of monitors used, mouse position, mouse usage, keyboard usage, and keyboard position) were investigated in terms of 17 items and judged as "adequate" or "inadequate." NUP was assessed using a numerical rating scale. NUP locations included the neck, shoulder, elbow, and wrist. In the statistical analysis, outcome variables were the presence of pain in each part, while explanatory variables were the number of inadequate workstations. Logistic regression analyses were conducted with adjustment for age, gender, working duration, and exercise habit. Results: The prevalence of neck pain was 47% (n = 143), shoulder pain was 50% (n = 153), elbow pain was 7.2% (n = 22), and wrist pain was 13% (n = 40). In the adjusted model, the number of inadequate workstations had significant positive associations with elbow pain (odds ratio [OR], 1.39; 95% confidence interval [CI], 1.06.1.81) and wrist pain (OR, 1.80; 95% CI, 1.17.2.26). However, the number of inadequate workstations was not significantly associated with neck pain or shoulder pain. Conclusions: Workstation-related factors (presence of armrest, armrest position, mouse usage, and keyboard usage) were significantly associated with elbow and wrist pain. Our findings suggest that workstations can contribute to elbow and wrist pain in office workers