Quantum tunneling time of a Bose-Einstein condensate traversing through a laser-induced potential barrier

We theoretically study the effect of atomic nonlinearity on the tunneling time in the case of an atomic Bose-Einstein condensate (BEC) traversing the laser-induced potential barrier. The atomic nonlinearity is controlled to appear only in the region of the barrier by employing the Feshbach resonance technique to tune interatomic interaction in the tunneling process. Numerical simulation shows that the atomic nonlinear effect dramatically changes the tunneling behavior of the BEC matter wave packet, and results in the violation of Hartman effect and the occurrence of negative tunneling time.Comment: 4 pages, 5 figure

Quantifying the short-term dynamics of soil organic carbon decomposition using a power function model

Introduction Soil heterotrophic respiration (R h, an indicator of soil organic carbon decomposition) is an important carbon efflux of terrestrial ecosystems. However, the dynamics of soil R h and its empirical relations with climatic factors have not been well understood. Methods We incubated soils of three subtropical forests at five temperatures (10, 17, 24, 31, and 38 °C) and five moistures (20, 40, 60, 80, and 100% water holding capacity (WHC)) over 90 days. R h was measured throughout the course of the incubation. Three types of models (log-linear, exponential, and power model) were fitted to the measurements and evaluated based on the coefficient of determination (r 2) and Akaike Information Criterion (AIC) of the model. Further regression analysis was used to derive the empirical relations between model parameters and the two climatic factors. Results Among the three models, the power function model (R h = R 1 t −k) performed the best in fitting the descending trend of soil R h with incubation time (r 2 \u3e 0.69 for 26 of 30 models). Both R 1 and k generally increased linearly with soil temperature but varied quadratically with soil moisture in the three forest soils. Conclusions This study demonstrated that the power function model was much more accurate than the exponential decay model in describing the decomposition dynamics of soil organic carbon (SOC) in mineral soils of subtropical forests. The empirical relations and parameter values derived from this incubation study may be incorporated into process-based ecosystem models to simulate R h responses to climate changes

Retrieval of phase memory in two independent atomic ensembles by Raman process

In spontaneous Raman process in atomic cell at high gain, both the Stokes field and the accompanying collective atomic excitation (atomic spin wave) are coherent. We find that, due to the spontaneous nature of the process, the phases of the Stokes field and the atomic spin wave change randomly from one realization to another but are anti-correlated. The phases of the atomic ensembles are read out via another Raman process at a later time, thus realizing phase memory in atoms. The observation of phase correlation between the Stokes field and the collective atomic excitations is an important step towards macroscopic EPR-type entanglement of continuous variables between light and atoms

We-Intention to Use Instant Messaging for Collaboration: A Social Influence Model

The purpose of this study is to introduce the concept of “we-intention” into group technology adoption and diffusion research. In this study, we examined the “we-intention” of using instant messaging for team collaboration. Building upon the social influence framework, a we-intention model is developed and tested with 163 respondents. The research model explained 41.3% of the variance in we-intention. Attitude, group norm and social identity were found to be statistically significant in determining we-intention to use instant messaging for collaboration, and value perception had significant effects on attitude and social influence factors. We believe that the implications of this study are important for both researchers and practitioners

Target selection of soluble protein complexes for structural proteomics studies

BACKGROUND: Protein expression in E. coli is the most commonly used system to produce protein for structural studies, because it is fast and inexpensive and can produce large quantity of proteins. However, when proteins from other species such as mammalian are produced in this system, problems of protein expression and solubility arise [1]. Structural genomics project are currently investigating proteomics pipelines that would produce sufficient quantities of recombinant proteins for structural studies of protein complexes. To investigate how the E. coli protein expression system could be used for this purpose, we purified apoptotic binary protein complexes formed between members of the Caspase Associated Recruitment Domain (CARD) family. RESULTS: A combinatorial approach to the generation of protein complexes was performed between members of the CARD domain protein family that have the ability to form hetero-dimers between each other. In our method, each gene coding for a specific protein partner is cloned in pET-28b (Novagen) and PGEX2T (Amersham) expression vectors. All combinations of protein complexes are then obtained by reconstituting complexes from purified components in native conditions, after denaturation-renaturation or co-expression. Our study applied to 14 soluble CARD domain proteins revealed that co-expression studies perform better than native and denaturation-renaturation methods. In this study, we confirm existing interactions obtained in vivoin mammalian cells and also predict new interactions. CONCLUSION: The simplicity of this screening method could be easily scaled up to identify soluble protein complexes for structural genomic projects. This study reports informative statistics on the solubility of human protein complexes expressed in E.coli belonging to the human CARD protein family

Inhibitory Effects of Dimeric Copper(II) bis(o-acetoxybenzoate) on Platelet-neutrophil adhesion and Thrombosis

Antithrombotic effect of the copper-aspirin complex (dimeric copper(II) bis(o-acetoxybenzoate) was evaluated in the model of venous thrombosis; its effects on platelet-neutrophil adhesion were investigated by use of rosette assay. The results showed that the intragastrically administered copper-aspirin complex (5, 7, and 10 mg kg-1) dose-dependently lowered the wet and dry thrombus weight; it significantly decreased the binding of arachidonic acid-activated platelets to neutrophils with an IC50 value of 41.5 μmol L-1. The results suggested that copper aspirinate inhibited platelet-neutrophil adhesion and resulted in a more potent antithrombotic activity

COST-EFF: Collaborative Optimization of Spatial and Temporal Efficiency with Slenderized Multi-exit Language Models

Transformer-based pre-trained language models (PLMs) mostly suffer from excessive overhead despite their advanced capacity. For resource-constrained devices, there is an urgent need for a spatially and temporally efficient model which retains the major capacity of PLMs. However, existing statically compressed models are unaware of the diverse complexities between input instances, potentially resulting in redundancy and inadequacy for simple and complex inputs. Also, miniature models with early exiting encounter challenges in the trade-off between making predictions and serving the deeper layers. Motivated by such considerations, we propose a collaborative optimization for PLMs that integrates static model compression and dynamic inference acceleration. Specifically, the PLM is slenderized in width while the depth remains intact, complementing layer-wise early exiting to speed up inference dynamically. To address the trade-off of early exiting, we propose a joint training approach that calibrates slenderization and preserves contributive structures to each exit instead of only the final layer. Experiments are conducted on GLUE benchmark and the results verify the Pareto optimality of our approach at high compression and acceleration rate with 1/8 parameters and 1/19 FLOPs of BERT.Comment: Accepted in EMNLP 2022 main conferenc

Potential Application of Copper Aspirinate in Preventing and Treating Thromboembolic Diseases

The efficacy of copper aspirinate against thrombotic diseases has been tested in animal models. The results show that copper aspirinate, following ig pretreatment for 7 days at 0.012mmol/kg markedly prolonged the bleeding time and inhibited the mortality induced by arachidonic acid (AA) in mice. On cereral ischemia model pretreatment with 0.018mmol/kg copper aspirinate ig significantly increased survival of animals and the density of intact hippocampal CA1 cells and decreased brain calcium concentration. Its anticerebral ischemia activity was superior to or equal to nimodipine. It is, therefore, suggested that copper aspirinate is very promising in becoming an antithrombotic drug in preventing and treating thrombotic diseases