1,872 research outputs found

    Dynamical generation of dark solitons in spin-orbit-coupled Bose-Einstein condensates

    Get PDF
    We numerically investigate the ground state, the Raman-driving dynamics and the nonlinear excitations of a realized spin-orbit-coupled Bose-Einstein condensate in a one-dimensional harmonic trap. Depending on the Raman coupling and the interatomic interactions, three ground-state phases are identified: stripe, plane wave and zero-momentum phases. A narrow parameter regime with coexistence of stripe and zero-momentum or plane wave phases in real space is found. Several sweep progresses across different phases by driving the Raman coupling linearly in time is simulated and the non-equilibrium dynamics of the system in these sweeps are studied. We find kinds of nonlinear excitations, with the particular dark solitons excited in the sweep from the stripe phase to the plane wave or zero-momentum phase within the trap. Moreover, the number and the stability of the dark solitons can be controlled in the driving, which provide a direct and easy way to generate dark solitons and study their dynamics and interaction properties.Comment: 10 pages, 9 figur

    Examining the effects of elevated CO2 on the growth kinetics of two microalgae, Skeletonema dohrnii (Bacillariophyceae) and Heterosigma akashiwo (Raphidophyceae)

    Get PDF
    Carbon dioxide (CO2) serves as the primary substrate for the photosynthesis of phytoplankton, forming the foundation of marine food webs and mediating the biogeochemical cycling of C and N. We studied the effects of CO2 variation on the Michaelis-Menten equations and elemental composition of Skeletonema dohrnii and Heterosigma akashiwo. CO2 functional response curves were conducted from 100 to 2000 ppm. The growth of both phytoplankton was significantly affected by CO2, but in different trends. The growth rate of S. dohrnii increased as CO2 levels rose up to 400 ppm before reaching saturation. In contrast to S. dohrnii, the growth rate of H. akashiwo increased with CO2 increasing up to 1000 ppm, and then CO2 saturated. In addition, H. akashiwo showed a slower growth rate than S. dohrnii for all CO2 concentrations, aside from 1000 ppm, and the Michaelis-Menten equations revealed that the half-saturation constant of H. akashiwo was higher than S. dohrnii. An increase in CO2 concentration was seen to significantly affected the POC: Chl-a of both S. dohrnii and H. akashiwo, however, the effects on their elemental composition were minimal. Overall, our findings indicate that H. akashiwo had a more positive reaction to elevated CO2 than S. dohrnii, and with higher nutrient utilization efficiency, while S. dohrnii exhibited higher carbon fixation efficiency, which is in line with their respective carbon concentrating mechanisms. Consequently, elevated CO2, either alone or in combination with other limiting factors, may significantly alter the relative relationships between these two harmful algal blooms (HAB) species over the next century

    Polymorphisms of CYP1A1 I462V and GSTM1 genotypes and lung cancer susceptibility in Mongolian

    Get PDF
    Aim: To study the genotype of cytochrome P450 1A1(CYP1A1) I462V and glutathions S-transferase M1( GSTM1) and the relationship of the genetic polymorphism of them with the susceptibility of lung cancer in Mongolia of China. 

Methods: Allele-specific PCR and a multiplex PCR were employed to identify the genotypes of I462V of CYP1A1 and GSTM1 in a case-control study of 210 lung cancer patients with bronchoscopy diagnosis and 210 matched controls free of malignancy.

Results: The frequencies of the variant CYP1A1(Val/Val) genotypes and GSTM1(-) in lung cancer groups were higher than that in control groups (15.24% vs 7.4% and 56.67% vs 40.95% ). The individuals who carried with CYP1A1(Val/Val) or GSTM1(-) genotype had a significantly higher risk of lung cancer, the OR is 2.56 and 1.89 respectively. Stratified histologically the relative risk increased to 2.6 - fold when the patients carried with two valine alleles than the ones carried one valine allele in cases of SCC. GSTM1(-) genotype is the risk factor of SCC (OR=2.39) and AC(OR=2.16). The presence of at least one Val allele of CYP1A1 and GSTM1(-), the risk of lung cancer was increased, the OR was 4.15 for one Val allele and GSTM1(-) and 2.67 for two Val alleles and GSTM1 Considering ages and smoking status, the risk of lung cancer increased when the age less than 50 who carried with CYP1A1 valine (one or two) alleles or the age during the 51 to 65 who carried with GSTM1(-) genotype. The light smokers with CYP1A1 valine alleles and GSTM1(-) have a high risk for lung cancer. No association was found between the light and heavy drinkers with the susceptibility of lung cancer and the genetic polymorphisms of CYP1A1 I462V and GSTM1(-). 

Conclusion: The valine allele of CYP1A1 was the risk factors of lung cancer especially for SCC and GSTM1(-) also was the risk factor of lung cancer and especially for SCC and AC of Mongolian, China. Light smoking has a influence each other with genotype of CYP1A1 I462V and GSTM1(-) and susceptibility of lung cancer. No relationship was found between the susceptibility of lung cancer and drinkers with genetic polymorphisms of CYP1A1 I462V and GSTM1(-). The influence of genotypes on the susceptibility of lung cancer may depend on the ages. There may be a synergetic interaction between CYP1A1 valine allele and GSTM1(-) genotypes on the elevated susceptibility of lung cancer. So do those genotypes with light smokers. Key words polymorphism; genotype; lung cancer; cytochrome P450;glutathione S-transferase Abbreviations: SCC, squamous cell carcinoma; AC, adenocarcinoma; SCLC, small cell lung cancer; LCLC, large cell lung cance

    Application of Rough Classification of Multi-objective Extension Group Decision-making under Uncertainty

    Get PDF
    On account of the problem of incomplete information system in classification of extension group decision-making, this paper studies attribution reduction with decision-making function based on the group interaction and individual preferences assembly for achieving the goal of rough classification of multi-objective extension group decision-making under uncertainty. Then, this paper describes the idea and operating processes of multi-objective extension classification model in order to provide decision-makers with more practical, easy to operate and objective classification. Finally, an example concerning practical problem is given to demonstrate the classification process. Combining by extension association and rough reduction, this method not only takes the advantages of dynamic classification in extension decision-making, but also achieves the elimination of redundant attributes, conducive to the promotion on the accuracy and the reliability of the classification results in multi-objective extension group decision-making. Keywords: extension group decision-making; matter-element analysis; extension association; rough set; attribution reductio

    Genetic polymorphisms of TLR3 are associated with Nasopharyngeal carcinoma risk in Cantonese population

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Nasopharyngeal carcinoma is endemic in Southern China, displays a strong relationship with genetic susceptibility and associates with Epstein-Barr virus infection. Toll-like receptor 3 (TLR3) plays an important role in the antivirus response. Therefore, we examined the association between <it>TLR3 </it>gene polymorphisms and NPC susceptibility.</p> <p>Methods</p> <p>We performed a case-control study of 434 NPC cases and 512 healthy controls matched on age, sex and residence. Both cases and controls are of Cantonese origin from Southern China. Genetic variants in <it>TLR3 </it>were determined by polymerase chain reaction (PCR)-based DNA direct sequencing and four SNPs were genotyped in all samples.</p> <p>Results</p> <p>Our results showed that allele C for SNP 829A/C increased NPC risk significantly ((p = 0.0068, OR = 1.49, 95%CI:1.10–2.00). When adjusted for age, gender and VCA-IgA antibody titers, the NPC risk was reduced significantly among individuals who carried the haplotype "ATCT" compared to those who carried the most common haplotype "ACCT" (p = 0.0054, OR = 0.028; 95% CI (0.002–0.341).</p> <p>Conclusion</p> <p>The <it>TLR3 </it>polymorphisms may be relevant to NPC susceptibility in the Cantonese population, although the reduction in NPC risk is modest and the biological mechanism of the observed association merits further investigation.</p

    Protection effect of sanguinarine on whole-body exposure of X radiation in BALB/c mice

    Get PDF
    To investigate the effects of sanguinarine (SAN) on acute radiation induced injury in mice, 45 mice were randomly divided into control, 10 Gy and SAN+10 Gy groups. Mice in the 10 Gy and SAN+10 Gy groups were exposed to single X-ray radiation with an accumulated dose of 10 Gy. Mice in the SAN+10 Gy group were administered intraperitoneally with 2.5 mg/kg body weight of SAN before radiation. Five days after radiation exposure, 5 mice from each group were sacrificed and samples of the small intestine, lung, spleen and liver were fixed for histopathological examinations. Compared with the 10 Gy group, radiation sickness was obviously delayed or attenuated in the SAN+10 Gy group. Survival analysis showed a significant difference between 2 radiation groups (PPara investigar os efeitos da sanguinarina (SAN) em lesões induzidas em ratos por radiação aguda, 45 ratos foram aleatoriamente divididos em grupo controle, grupo 10 Gy e grupo SAN+10 Gy. Os ratos dos grupos 10 Gy e SAN+10 Gy foram expostos à radiação de raio-X simples com uma dose acumulada de 10 Gy. Aos ratos do grupo SAN+10 Gy administraram-se, intraperitonealmente, 2.5 mg/kg de peso de SAN antes da radiação. Aos 5 dias de exposição à radiação, sacrificaram-se 5 ratos de cada grupo e retiraram-se amostras do intestino delgado, pulmões, baço e fígado para exames histopatológicos. Comparando com o grupo 10 Gy, a doença por radiação foi claramente atrasada e atenuada no grupo SAN+10 Gy. A análise de sobrevivência mostrou diferença significativa entre os dois grupos de radiação (

    DisenPOI: Disentangling Sequential and Geographical Influence for Point-of-Interest Recommendation

    Full text link
    Point-of-Interest (POI) recommendation plays a vital role in various location-aware services. It has been observed that POI recommendation is driven by both sequential and geographical influences. However, since there is no annotated label of the dominant influence during recommendation, existing methods tend to entangle these two influences, which may lead to sub-optimal recommendation performance and poor interpretability. In this paper, we address the above challenge by proposing DisenPOI, a novel Disentangled dual-graph framework for POI recommendation, which jointly utilizes sequential and geographical relationships on two separate graphs and disentangles the two influences with self-supervision. The key novelty of our model compared with existing approaches is to extract disentangled representations of both sequential and geographical influences with contrastive learning. To be specific, we construct a geographical graph and a sequential graph based on the check-in sequence of a user. We tailor their propagation schemes to become sequence-/geo-aware to better capture the corresponding influences. Preference proxies are extracted from check-in sequence as pseudo labels for the two influences, which supervise the disentanglement via a contrastive loss. Extensive experiments on three datasets demonstrate the superiority of the proposed model.Comment: Accepted by ACM International Conference on Web Search and Data Mining (WSDM'23
    corecore