155 research outputs found
Analyzing the Impact of Food Safety Information on Food Demand in China
This study analyzed the impact of food safety information on food demand in urban China. The LA/AIDS model was estimated by using national province level food consumption data and quantities of articles about food safety event on public media from 2000 to 2008. The results of the study show that urban Chinese consumer food demand was influenced by food safety information from daily newspapers and GM labeling policy. This paper also indicates food price elasticities, expenditure elasticities by categories and the effect of food safety information.food safety, food demand, Linear Approximated Almost Ideal Demand System( LA/AIDS), Genetically modified( GM), food consumption, price elasticity, expenditure elasticity, Consumer/Household Economics, Demand and Price Analysis, Food Consumption/Nutrition/Food Safety, D12, Q11,
Unveiling the relative efficacy, safety and tolerability of prophylactic medications for migraine: pairwise and network-meta analysis
Ranking of migraine interventions using SUCRA values. (DOCX 17 kb
Model Selection for Topic Models via Spectral Decomposition
Abstract Topic models have achieved significant successes in analyzing large-scale text corpus. In practical applications, we are always confronted with the challenge of model selection, i.e., how to appropriately set the number of topics. Following the recent advances in topic models via tensor decomposition, we make a first attempt to provide theoretical analysis on model selection in latent Dirichlet allocation. With mild conditions, we derive the upper bound and lower bound on the number of topics given a text collection of finite size. Experimental results demonstrate that our bounds are correct and tight. Furthermore, using Gaussian mixture model as an example, we show that our methodology can be easily generalized to model selection analysis in other latent models
Photo-Otto engine with quantum correlations
We theoretically prose and investigate a photo-Otto engine that is working
with a single-mode radiation field inside an optical cavity and alternatively
driven by a hot and a cold reservoir, where the hot reservoir is realized by
sending one of a pair of correlated two-level atoms to pass through the optical
cavity, and the cold one is made of a collection of noninteracting boson modes.
In terms of the quantum discord of the pair of atoms, we derive the analytical
expressions for the performance parameters (power and efficiency) and stability
measure (coefficient of variation for power). We show that quantum discord
boosts the performance and efficiency of the quantum engine, and even may
change the operation mode. We also demonstrate that quantum discord improves
the stability of machine by decreasing the coefficient of variation for power
which satisfies the generalized thermodynamic uncertainty relation. Finally, we
find that these results can be transferred to another photo-Otto engine model,
where the optical cavity is alternatively coupled to a hot thermal bosonic bath
and to a beam of pairs of the two correlated atoms that play the role of a cold
reservoir
NASRec: Weight Sharing Neural Architecture Search for Recommender Systems
The rise of deep neural networks provides an important driver in optimizing
recommender systems. However, the success of recommender systems lies in
delicate architecture fabrication, and thus calls for Neural Architecture
Search (NAS) to further improve its modeling. We propose NASRec, a paradigm
that trains a single supernet and efficiently produces abundant
models/sub-architectures by weight sharing. To overcome the data multi-modality
and architecture heterogeneity challenges in recommendation domain, NASRec
establishes a large supernet (i.e., search space) to search the full
architectures, with the supernet incorporating versatile operator choices and
dense connectivity minimizing human prior for flexibility. The scale and
heterogeneity in NASRec impose challenges in search, such as training
inefficiency, operator-imbalance, and degraded rank correlation. We tackle
these challenges by proposing single-operator any-connection sampling,
operator-balancing interaction modules, and post-training fine-tuning. Our
results on three Click-Through Rates (CTR) prediction benchmarks show that
NASRec can outperform both manually designed models and existing NAS methods,
achieving state-of-the-art performance
Association of miR-196a2 and miR-27a polymorphisms with gestational diabetes mellitus susceptibility in a Chinese population
IntroductionMiR-196a2 and miR-27a play a key role in the regulation of the insulin signaling pathway. Previous studies have indicated that miR-27a rs895819 and miR-196a2 rs11614913 have a strong association with type 2 diabetes (T2DM), but very few studies have investigated their role in gestational diabetes mellitus (GDM).MethodsA total of 500 GDM patients and 502 control subjects were enrolled in this study. Using the SNPscan™ genotyping assay, rs11614913 and rs895819 were genotyped. In the data treatment process, the independent sample t test, logistic regression and chi-square test were used to evaluate the differences in genotype, allele, and haplotype distributions and their associations with GDM risk. One-way ANOVA was conducted to determine the differences in genotype and blood glucose level.ResultsThere were obvious differences in prepregnancy body mass index (pre-BMI), age, systolic blood pressure (SBP), diastolic blood pressure (DBP) and parity between GDM and healthy subjects (P < 0.05). After adjusting for the above factors, the miR-27a rs895819 C allele was still associated with an increased risk of GDM (C vs. T: OR=1.245; 95% CI: 1.011-1.533; P = 0.039) and the TT-CC genotype of rs11614913-rs895819 was related to an increased GDM risk (OR=3.989; 95% CI: 1.309-12.16; P = 0.015). In addition, the haplotype T-C had a positive interaction with GDM (OR=1.376; 95% CI: 1.075-1.790; P=0.018), especially in the 18.5 ≤ pre-BMI < 24 group (OR=1.403; 95% CI: 1.026-1.921; P=0.034). Moreover, the blood glucose level of the rs895819 CC genotype was significantly higher than that of the TT and TC genotypes (P < 0.05). The TT-CC genotype of rs11614913-rs895819 showed that the blood glucose level was significantly higher than that of the other genotypes.DiscussionOur findings suggest that miR-27a rs895819 is associated with increased GDM susceptibility and higher blood glucose levels
Molecular basis of ligand recognition and activation of human V2 vasopressin receptor.
Vasopressin type 2 receptor (V2R) belongs to the vasopressin (VP)/oxytocin (OT) receptor subfamily of G protein-coupled receptors (GPCRs), which comprises at least four closely related receptor subtypes: V1aR, V1bR, V2R, and OTR. These receptors are activated by arginine vasopressin (AVP) and OT, two endogenous nine-amino acid neurohypophysial hormones, which are thought to mediate a biologically conserved role in social behavior and sexual reproduction. V2R is mainly expressed in the renal collecting duct principal cells and mediates the antidiuretic action of AVP by accelerating water reabsorption, thereby playing a vital role in controlling water homeostasis. Moreover, numerous gain-of-function and loss-of-function mutations of V2R have been identified and are closely associated with human diseases, including nephrogenic syndrome of inappropriate diuresis (NSIAD) and X-linked congenital nephrogenic diabetes insipidus (NDI). Thus, V2R has attracted intense interest as a drug target. However, due to a lack of structural information, how AVP recognizes and activates V2R remains elusive, which hampers the V2R-targeted drug design. Here, we determined a 2.6 Å resolution cryo-EM structure of the full-length, G s -coupled human V2R bound to AVP (Fig. 1a; Supplementary information, Table S1). The G s protein was engineered based on mini-G s that was used in the crystal structure determination of the G s -coupled adenosine A 2A receptor (A 2A R) to stabilize the V2R–G s protein complex (Supplementary information, Data S1). The final structure of the AVP–V2R–G s complex contains all residues of AVP (residues 1–9), the Gα s Ras-like domain, Gβγ subunits, Nb35, scFv16, and the V2R residues from T31 to L339 8.57 (superscripts refer to Ballesteros–Weinstein numbering). The majority of amino acid side chains, including AVP, transmembrane domain (TMD), all flexible intracellular loops (ICLs) and extracellular loops (ECLs) except for ICL3 and G185–G188 in ECL2, were well resolved in the model, refined against the EM density map (Fig. 1a; Supplementary information, Figs. S1–3). The complex structure can provide detailed information on the binding interface between AVP and helix bundle of the receptor, as well as the receptor–G s interface
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