Performance of TF-VLS Grown InP Photovoltaic Cells

A grand challenge of photovoltaics (PV) is to find materials offering a promising combination of low costs and high efficiencies. While III-V material-based PV cells have set many world records, often their cost is much greater than other commercial cells. To help address this gap, thin-film vapor-liquid-solid (TF-VLS) grown Indium Phosphide (InP) PV cells have recently been developed, which both eliminate a key source of high costs and offer a direct bandgap of 1.34eV with potential to approach maximum theoretical efficiencies. However, the unanticipated phenomenon of open circuit voltage (Voc) degradation has prevented TF-VLS grown InP PV cells from achieving their theoretical efficiencies, which appears to be caused by effective bandgap narrowing in certain portions of the cells. To address this issue, we have developed a 3D model for these PV cells in Xyce, a SPICE-like free circuit modeling software. Our model quantifies lateral variation of TF-VLS grown cells observed in photoluminescence (PL) images with two sets of unit cell parameters. It turns out that the PL intensity correlates to PV cells of different bandgaps (Eg). Based on user-defined cutoffs, we are able to categorize the expected bandgap and reduced bandgap cells. With the addition of an appropriate shunt resistance, it is possible to explain most of current-voltage relationship with this model. Finally, we are building a web-enabled tool to allow users to upload their own heterogeneous PV cell data into our model, using a graphical user interface on nanoHUB.org, an open-access science gateway for cloud-based simulation tools and resources for research and education in nanoscale science and technology

Deconfounding Causal Inference for Zero-shot Action Recognition

Zero-shot action recognition (ZSAR) aims to recognize unseen action categories in the test set without corresponding training examples. Most existing zero-shot methods follow the feature generation framework to transfer knowledge from seen action categories to model the feature distribution of unseen categories. However, due to the complexity and diversity of actions, it remains challenging to generate unseen feature distribution, especially for the cross-dataset scenario when there is potentially larger domain shift. This paper proposes a De confounding Ca usa l GAN (DeCalGAN) for generating unseen action video features with the following technical contributions: 1) Our model unifies compositional ZSAR with traditional visual-semantic models to incorporate local object information with global semantic information for feature generation. 2) A GAN-based architecture is proposed for causal inference and unseen distribution discovery. 3) A deconfounding module is proposed to refine representations of local object and global semantic information confounder in the training data. Action descriptions and random object feature after causal inference are then used to discover unseen distributions of novel actions in different datasets. Our extensive experiments on C ross- D ataset Z ero- S hot A ction R ecognition (CD-ZSAR) demonstrate substantial improvement over the UCF101 and HMDB51 standard benchmarks for this problem

Iron accumulation in the ventral tegmental area in Parkinson's disease

IntroductionThe ventral tegmental area (VTA) is less affected compared to substantia nigra pars compacta (SNc) in Parkinson's disease (PD). This study aimed to quantitatively evaluate iron content in the VTA across different stages of PD in order to help explain the selective loss of dopamine neurons in PD.MethodsQuantitative susceptibility mapping (QSM) data were obtained from 101 PD patients, 35 idiopathic rapid eye movement sleep behavior disorder (RBD) patients, and 62 healthy controls (HCs). The mean QSM values in the VTA and SNc were calculated and compared among the groups.ResultsBoth RBD and PD patients had increased iron values in the bilateral SNc compared with HCs. RBD and PD patients in the Hoehn–Yahr (H & Y) stage 1 did not show elevated iron values in the VTA, while PD patients with more than 1.5 H & Y staging had increased iron values in bilateral VTA compared to HCs.DiscussionThis study shows that there is no increased iron accumulation in the VTA during the prodromal and early clinical stages of PD, but iron deposition increases significantly as the disease becomes more severe

Tree-ring stable carbon isotope-based April-June relative humidity reconstruction since AD 1648 in Mt. Tianmu, China

Based on accurate dating, we have determined the stable carbon isotope ratios (delta C-13) of five Cryptomeria fortunei specimens from Mt. Tianmu, a subtropical area in southern China. The five delta C-13 time series records are combined into a single representative delta C-13 time series using a "numerical mix method." These are normalized to remove temporal variations of delta(13) C in atmospheric CO2 to obtain a carbon isotopic discrimination (Delta C-13) time series, in which we observe a distinct correlation between Delta C-13 and local April to June mean relative humidity (RH (AMJ) ) (n = 64, r = 0.858, p < 0.0001). We use this relationship to reconstruct RH (AMJ) variations from ad 1648 to 2014 at Mt. Tianmu. The reconstructed sequence show that over the past 367 years, Mt. Tianmu area was relatively wet, but in the latter part of the twentieth century, under the influence of increasing global warming, it has experienced a sharp reduction in relative humidity. Spatial correlation analysis reveals a significant negative correlation between RH (AMJ) at Mt. Tianmu and Sea Surface Temperature (SSTs) in the western equatorial Pacific and Indian Ocean. In other words, there is a positive correlation between tree-ring delta C-13 in Mt. Tianmu and SSTs. Both observed and reconstructed RH (AMJ) show significant positive correlations with East Asian and South Asian monsoons from 1951 to 2014, which indicate that RH (AMJ) from Mt. Tianmu reflects the variability of the Asian summer monsoon intensity to a great extent. The summer monsoon has weakened since 1960. However, an increase in relative humidity since 2003 implies a recent enhancement in the summer monsoon

Experimental study on the effect of different air supply temperature on forced-air precooling of lettuce

During the forced-air precooling, the air supply temperature was the cold storage environment temperature. The air supply temperature was the most important factor to impact the fruits and vegetables precooling time and energy consumption in the condition of constant wind speed. In this experiment, the head lettuces precooled from 22 ℃ to 3 ℃. From 22 ℃ to half cooling time, it was selected 0 ℃, 2℃ and 4℃ as the air supply temperature in the precooling process of lettuces. Next the precooling was carried out from the half cooling time to 3°C at the blowing temperature of 0°C. The results were indicated that the air supply temperature changed from 2°C to 0°C was the best pre-cooling program to cooling down and save energy. In the actual production, it could develop the changed air temperature pre-cooling technology vigorously

Effects of different transportation methods on quality maintenance of peach 'Okubao' after forced-air cooling

The goal of this research was to evaluate the efficiency of various simulated transport treatments on maintaining the quality of 'Okubao' peach. Peaches were pre-cooled to 5oC for 140 minutes and afterwards treated with three simulated transport treatments, consisting of cold transportation with or without 35 um anti-fogging cast polypropylene (CPP) plastic package, and detachable incubator. Parameters evaluated included sensory quality, weight loss, color, flesh firmness, soluble solids content, titratable acidity, soluble sugar and ascorbic acid concentration. Weight loss of fruits was reduced tremendously, lower than 1%.The appearance, soluble solids content, titratable acidity, soluble sugar and overall sensory quality of the wrapped peaches transported at 0oC were found to be better than those unwrapped and transported by incubator. Transportation at 0oC in CPP was shown most useful to prevent weight losses and maintain fruit color, freshness and nutritional values

Effects of forced-air precooling, °C transportation and different retailing methods on the quality of peach

The objective of this experiment was to evaluate the effects of different retailing methods on the maintenance of peach quality after pre-cooled to 5°C and transportation at 0°C. ‘Okubao’ peaches were film wrapped using 35 um anti-fogging cast polypropylene (CPP) and stored for 3 days at 0°C or 4°C to simulate refrigerated display cabinet condition. Some other peached directly stored at 20°C unwrapped after transportation. Results revealed that softening and deterioration occurred quickly in 20°C. Peach stored in 20°C lost significantly more weight, 3.7%. 0°C and 4°C resulted in less weight loss of the packaged peach, 0.7% and 1.7%, respectively. After shelf life, 0°C retailed peach wrapped in CPP showed the highest sensory quality, lost less weight, was firmest, and retained color better than either 4°C or 20°C retailed peach. Additionally, soluble solids content, titratable acidity, soluble sugar and ascorbic acid concentration significantly remained when retailed at 0°C

Life cycle exposure to 2-phenylbenzimidazole-5-sulfonic acid disrupts reproductive endocrine system and induces transgenerational adverse effects in zebrafish

Global attention has been focused on organic UV filters due to their ubiquity and potential damage to aquatic environment, yet the effects of their life cycle exposure on fish reproduction remain unknown. In the present study, the influence of 2-phenylbenzimidazole-5-sulfonic acid (PBSA) exposure on the reproductive endocrine system of zebrafish was examined, from 6 hours post fertilization (hpf) until 150 days, at levels that near-environmentally relevant (0 to 20 μg/L). Our results showed that exposure to PBSA at 20 μg/L caused a slight decrease in the Gonadosomatic Index (GSI) of female zebrafish in the F0 generation. Furthermore, this exposure had a negatively effect on reproduction, accompanied by delayed oocyte maturation, reduced cumulative egg production and decreased fertilization rate. Additionally, offspring embryos displayed reduced egg diameter at 0.75 hpf, delayed cumulative hatching rate at 60 hpf, and increased deformities rate at 72 hpf, indicating an adverse transgenerational effect. Moreover, PBSA exposure was associated with decreased plasma levels of sex hormones of 17β-estradiol (E2) and 11-ketotestosterone (11-KT), as well as altered the transcriptional profiles of certain genes in the HPG (hypothalamic–pituitary–gonadal) and liver axis. Molecular docking (MD) simulations revealed that specific amino acid residues of PBSA interact with zebrafish estrogen receptors, confirming its xenoestrogenic properties. Therefore, exposure to PBSA during its life cycle can disturb fish reproduction through endocrine disruption, thus necessitating strict environmental regulations for the disposal of UV filters to protect ecological and public health

Chronic and Cumulative Adverse Life Events in Women with Primary Ovarian Insufficiency:An Exploratory Qualitative Study

BACKGROUND AND PURPOSE: Primary ovarian insufficiency (POI) has serious physical and psychological consequences due to estradiol deprivation, leading to increased morbidity and mortality. However, the causes of most POI cases remain unknown. Psychological stress, usually caused by stressful life events, is known to be negatively associated with ovarian function. It is important to explore high-frequency adverse life events among women with POI for future interventions. METHODS: Forty-three women (mean age=33·8 years) were recruited who were newly- diagnosed with idiopathic POI (FSH levels >40 IU/L) to participate in semi-structured interviews through convenience sampling. The main questions covered by the topic guide were designed to explore adverse life events prior to POI diagnosis. Interviews were audio recorded, transcribed and analyzed thematically. Data were analyzed from June 2019 to August 2020. RESULTS: Among the women with POI, mean age at diagnosis of POI was 33·8 years (range from 19 to 39 years), and the average time between the onset of irregular menstruation and POI diagnosis was 2.3 years. These women with POI had a relatively normal menstrual cycle before the diagnosis. A number of stressful life events prior to POI diagnosis were discussed by them as important factors influencing their health. Four core themes emerged: 1) persistent exposure to workplace stress, 2) persistent exposure to family-related adverse life events, 3) sleep problem/disturbance existed in women with POI before diagnosis, and 4) participants’ general cognition and concerns about POI. CONCLUSIONS: Persistent exposures to adverse life events related to work stress, family stress and sleep problem existed in women with POI. Our findings are consistent with the hypothesis that adverse life events play a role in the development of POI. Future research should investigate how social environmental factors influence POI disease risks, and whether provision of tailored interventions (i.e. preventing or mitigating impact of adverse life events) aimed at high-risk populations may help prevent new POI cases and improve conditions of women with POI. We gained an in-depth understanding of the experiences of these women via 1:1 qualitative method, and find adverse life events are frequent in women with POI prior to the diagnosis