Understanding excited carrier dynamics in semiconductors is crucial for the development of photovoltaics and efficient photonic devices. However, overlapping spectral features in optical pump-probe ...spectroscopy often render assignments of separate electron and hole carrier dynamics ambiguous. Here, ultrafast electron and hole dynamics in germanium nanocrystalline thin films are directly and simultaneously observed by ultrafast transient absorption spectroscopy in the extreme ultraviolet at the germanium M
edge. We decompose the spectra into contributions of electronic state blocking and photo-induced band shifts at a carrier density of 8 × 10
cm
. Separate electron and hole relaxation times are observed as a function of hot carrier energies. A first-order electron and hole decay of ∼1 ps suggests a Shockley-Read-Hall recombination mechanism. The simultaneous observation of electrons and holes with extreme ultraviolet transient absorption spectroscopy paves the way for investigating few- to sub-femtosecond dynamics of both holes and electrons in complex semiconductor materials and across junctions.
We present a novel denoising scheme for spectroscopy experiments employing broadband light sources and demonstrate its capabilities using transient absorption measurements with a high-harmonic ...source. Our scheme relies on measuring the probe spectra before and after interacting with the sample while capturing correlations between spectral components through machine learning approaches. With the present setup we achieve up to a tenfold improvement in noise suppression in XUV transient absorption spectra compared to the conventional pump on/ pump off referencing method. By utilizing strong spectral correlations in source fluctuations, the use of an artificial neural network facilitates pixel-wise noise reduction without requiring wavelength calibration of the reference spectrum. Our method can be adapted to a wide range of experiments and may be particularly advantageous for low repetition-rate systems, such as free electron lasers as well as laser-driven plasma and HHG sources. The enhanced sensitivity enables the investigation of subtle electron and lattice dynamics in the weak excitation regime, which is relevant for studying photovoltaics and photo-induced phase transitions in strongly correlated materials.
The main purpose of this study is to how to enhance the green product development performance from the perspectives of green vision and organizational culture. This study explores the influences of a ...green shared vision and the environmental organizational culture on the green product development performance in Taiwan's manufacturing industry. It also examines the mediation effect of the green absorptive capacity. The empirical results indicate that both the green shared vision and environmental organizational culture have positive effects on the green absorptive capacity, which in turn positively affects the green product development performance. In particular, the green absorptive capacity completely mediates the relationship between the green shared vision and green product development performance, whereas it partially mediates the relationship between the environmental organizational culture and green product development performance.
•Experimental studies of the ORC system operating with R245fa are presented.•Scroll type expander was employed in the ORC system.•The cycle was fueled with hot water (maximum 95.6°C).•Superheating ...improves isentropic efficiency of the expander.
This paper focuses on experimental performance of an open-drive scroll type expander in an organic Rankine cycle (ORC) system. The expander was an originally oil-free scroll type air compressor with a built-in volume ratio of 4.05. The cycle used HFC-245fa as working fluid, and the loop has been mixed with a moderate concentration of refrigerant oil that circulated in the cycle. The experimental results of this study are divided into two main parts: first part focuses the experimental performance on the fixed superheating at the expander inlet with respect to various pressure differences of the system and rotational speeds of the expander. Second part involves various superheating at the expander inlet which was operated at fixed rotational speed and operating pressure difference of 5bars and 6bars. When the cycle was operated under fixed superheating conditions, the maximum cycle efficiency, expander efficiency and power output of the expander are 9.44%, 73.1% and 2.3kW respectively. On the other hand, when the expander is operated in various superheating conditions, the expander and cycle efficiency simultaneously increase with the increasing of superheating. In addition, this paper not only focuses on the experimental results using the current expander, but also integrates the previous experimental data with present study to identify an appropriate scroll type expander with respect to various operating pressure differences for the heat source below 100°C.
Background
ADH1B rs1229984 and ALDH2 rs671 are the specifically prevalent functional variants in the East Asians. These variants, which result in a dramatic change in enzyme activity, are highly ...associated with alcohol‐related disorders and cancer. Previous studies focusing on the additive and synergic effects of the variants are few and inconsistent. The aim of the research was to evaluate the associations of ADH1B rs1229984 and ALDH2 rs671 with the risks of alcohol‐related disorder and cancer.
Methods
This cohort study enrolled 42,665 participants from the Taiwan Precision Medicine Initiative database, including 19,522 and 20,534, ADH1B and ALDH2 carriers, respectively. The associations between the two variants and cancer risk were analyzed by univariable and multivariable logistic regression.
Results
Compared with the noncarriers, the ADH1B rs1229984 variant had a stronger effect on alcohol‐related disorders and was related to an increased risk of alcohol‐related cancers. The CC genotype of ADH1B rs1229984 was significantly associated with cancer of the larynx, pharynx, and nasal cavities odds ratio (OR) = 1.56, p = 0.0009, cancer of the pancreas (OR = 1.66, p = 0.018), and cancer of the esophagus (OR = 4.10, p < 0.001). Participants who carried the rs1229984 TC/CC and rs671 GG genotypes were at higher risk of esophageal cancer (OR = 3.02, p < 0.001). The risk of esophageal cancer was increased by 381% (OR = 4.81, p < 0.001) in those carrying the rs1229984 TC/CC and rs671 GA/AA genotypes.
Conclusion
rs1229984 and rs671 are common and functionally important genetic variants in the Taiwanese population. Our findings provide strong evidence of additive and synergic risks of ADH1B and ALDH2 variants for alcohol‐related disorders and cancer. The results suggested that are reduction in alcohol consumption should be advised as a preventive measure for high‐risk patients carrying ADH1B rs1229984 C or the ALDH2 rs671 A allele.
Figure. The Flow char for selection of the study population (A), and the PheWAS Manhattan and QQ plots for ADH1B rs1229984 (B) and ALDH2 rs671 (C), respectively Brief Summary Our findings provide evidence of additive and synergic risks of the ADH1B and ALDH2 variants for alcohol‐related disorder and cancer. These results suggested that reduction of alcohol consumption should be advised as a preventive measure for high‐risk patients carrying the ADH1B rs1229984 C or the ALDH2 rs671 A allele.
The small polaron quantum master equation (SPQME) proposed by Jang et al. J. Chem. Phys. 129, 101104 (2008) is a promising approach to describe coherent excitation energy transfer dynamics in complex ...molecular systems. To determine the applicable regime of the SPQME approach, we perform a comprehensive investigation of its accuracy by comparing its simulated population dynamics with numerically exact quasi-adiabatic path integral calculations. We demonstrate that the SPQME method yields accurate dynamics in a wide parameter range. Furthermore, our results show that the accuracy of polaron theory depends strongly upon the degree of exciton delocalization and timescale of polaron formation. Finally, we propose a simple criterion to assess the applicability of the SPQME theory that ensures the reliability of practical simulations of energy transfer dynamics with SPQME in light-harvesting systems.
Designing in‐plane‐oriented light‐emitting dipoles is known as a critical method to develop high‐efficiency organic light‐emitting diodes (OLEDs) by enhancing light extraction. However, ...in‐plane‐oriented light‐emitting dipoles must demonstrate sufficient polarization memory extended into light emission lifetime window, generating extended anisotropy dynamics shown as the necessary condition to increase light extraction toward developing high‐efficiency OLEDs. This paper reports experimental studies on anisotropy dynamics of light‐emitting dipoles in both time and energy domains by using time‐resolved and steady‐state photoluminescence anisotropy measurements based on the in‐plane oriented exciplex‐heterostructured BCzPh:CN‐T2T host dispersed with phosphorescent molecules. It is found that, when host–guest Coulomb scattering is suppressed by parallel placing of the in‐plane‐configured phosphorescent Ir(ppy)2(acac) molecules into the in‐plane‐oriented exciplex‐heterostructured BCzPh:CN‐T2T host, the anisotropy dynamics of light‐emitting dipoles can be extended into microseconds time window comparable with its phosphorescence lifetime, satisfying the necessary condition in time domain to increase light out‐coupling efficiency toward developing high external quantum efficiencies (EQEs) in Ir(ppy)2(acac):exciplex system. More importantly, by suppressing host–guest Coulomb scattering, the high‐energy transition dipoles can still maintain extended anisotropy dynamics in the energy domain in Ir(ppy)2(acac):exciplex system while hot electrons are relaxing toward lowest unoccupied molecular orbital (LUMO). Consequently, the extended anisotropy dynamics of light‐emitting dipoles demonstrate a high EQE of 34.01% in the Ir(ppy)2(acac):exciplex OLED.
Anisotropy dynamics of light‐emitting dipoles in both time and energy domains are investigated to reveal extended anisotropy dynamics in exciplex:Ir(ppy)2(acac) light‐emitting system. The anisotropy‐enhanced system can take advantage of the high horizontally oriented dipole ratio of exciplex during the energy transfer process, contributing to the light out‐coupling efficiency in organic light‐emitting diodes (OLEDs). Consequently, Ir(ppy)2(acac):exciplex OLED demonstrates a high external quamtum efficiency of 34.01%.
Attosecond transient absorption spectroscopy (ATAS) is used to observe photoexcited dynamics with outstanding time resolution. The main experimental challenge of this technique is that high-harmonic ...generation sources show significant instabilities, resulting in sub-par sensitivity when compared to other techniques. This paper proposes edge-pixel referencing as a means to suppress this noise. Two approaches are introduced: the first is deterministic and uses a correlation analysis, while the second relies on singular value decomposition. Each method is demonstrated and quantified on a noisy measurement taken on WS
and results in a fivefold increase in sensitivity. The combination of the two methods ensures the fidelity of the procedure and can be implemented on live data collection but also on existing datasets. The results show that edge-referencing methods bring the sensitivity of ATAS near the detector noise floor. An implementation of the post-processing code is provided to the reader.
Objective To evaluate whether very early treatment in our patients would result in better clinical outcomes and to compare these data with other infantile-onset Pompe disease (IOPD) cohort studies. ...Methods In this nationwide program, 669 797 newborns were screened for Pompe disease. We diagnosed IOPD in 14 of these newborns, and all were treated and followed in our hospital. Results After 2010, the mean age at first enzyme-replacement therapy (ERT) was 11.92 days. Our patients had better biological, physical, and developmental outcomes and lower anti-rh acid α-glucosidase antibodies after 2 years of treatment, even compared with one group that began ERT just 10 days later than our cohort. No patient had a hearing disorder or abnormal vision. The mean age for independent walking was 11.6 ± 1.3 months, the same age as normal children. Conclusions ERT for patients with IOPD should be initiated as early as possible before irreversible damage occurs. Our results indicate that early identification of patients with IOPD allows for the very early initiation of ERT. Starting ERT even a few days earlier may lead to better patient outcomes.
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