Spin Excitation Spectra of Anisotropic Spin-1/2 Triangular Lattice Heisenberg Antiferromagnets.

Investigation of dynamical excitations is difficult but crucial to the understanding of many exotic quantum phenomena discovered in quantum materials. This is particularly true for highly frustrated quantum antiferromagnets whose dynamical properties deviate strongly from theoretical predictions made based on the spin-wave or other approximations. Here, we present a large-scale numerical calculation on the dynamical correlation functions of spin-1/2 triangular Heisenberg model using a state-of-the-art tensor network renormalization group method. The calculated results allow us to gain for the first time a comprehensive picture on the nature of spin excitation spectra in this highly frustrated quantum system. It provides a quantitative account for all the key features of the dynamical spectra disclosed by inelastic neutron scattering measurements for Ba_{3}CoSb_{2}O_{9}, revealing the importance of the interplay between low- and high-energy excitations and its renormalization effect to the low-energy magnon bands and high-energy continuums. We identify the longitudinal Higgs modes in the intermediate-energy scale and predict the energy and momentum dependence of spectral functions along the three principal axes that can be verified by polarized neutron scattering experiments. Furthermore, we find that the spin excitation spectra weakly depend on the anisotropic ratio of the antiferromagnetic interaction.

Characterization of genetic fundamentals for piglet mortality at birth in Yorkshire, Landrace, and Duroc sows.

Piglet mortality is an economically important complex trait that impacts sow prolificacy. Genetic analyses for piglet mortality at weaning have been reported in dozens of studies, but not for piglet mortality at birth. In this study, we used multi-breed data sets from Yorkshire, Landrace, and Duroc sows to characterize the genetic fundamentals of piglet mortality at birth. The heritabilities from parity I to III were estimated to be 0.0630, 0.1031, and 0.1140 respectively. By using a combined strategy, a total of 21 SNPs were detected in three parities, of which six were observed in parity I, five in parity II and 10 in parity III. Genome annotation revealed that these SNPs were harbored within or close to 19 candidate genes. The candidate genes were found to associate with the reproductive system and embryonic development in the tissue expression database, which are reasonably related to piglet mortality. These findings are expected to provide much information for understanding the genetic and genomic fundamentals of farrowing mortality.

[An investigation and analysis on a poisoning tetramine accident].

From August 21 to December 13, 2018, a tetramine poisoning incident in Wenzhou, Zhejiang Province was investigated, and the clinical diagnosis and treatment of tetramine poisoning was analyzed. There were 6 cases of poisoning caused by artificial tetramine poisoning. The diagnosis was delayed, coma and convulsions were severe manifestations continuous renal replacement therapy (CRRT) was effective in the treatment of severe cases, and all 6 cases were cured. The possibility of poisoning should be considered for unexplained coma and/or convulsions. Although tetramine is banned, it still needs to be highly vigilant and avoids the recurrence of delayed diagnosis and treatment.

Gapless Spin-Liquid Ground State in the S=1/2 Kagome Antiferromagnet.

The defining problem in frustrated quantum magnetism, the ground state of the nearest-neighbor S=1/2 antiferromagnetic Heisenberg model on the kagome lattice, has defied all theoretical and numerical methods employed to date. We apply the formalism of tensor-network states, specifically the method of projected entangled simplex states, which combines infinite system size with a correct accounting for multipartite entanglement. By studying the ground-state energy, the finite magnetic order appearing at finite tensor bond dimensions, and the effects of a next-nearest-neighbor coupling, we demonstrate that the ground state is a gapless spin liquid. We discuss the comparison with other numerical studies and the physical interpretation of this result.

Majorana Positivity and the Fermion Sign Problem of Quantum Monte Carlo Simulations.

The sign problem is a major obstacle in quantum Monte Carlo simulations for many-body fermion systems. We examine this problem with a new perspective based on the Majorana reflection positivity and Majorana Kramers positivity. Two sufficient conditions are proven for the absence of the fermion sign problem. Our proof provides a unified description for all the interacting lattice fermion models previously known to be free of the sign problem based on the auxiliary field quantum Monte Carlo method. It also allows us to identify a number of new sign-problem-free interacting fermion models including, but not limited to, lattice fermion models with repulsive interactions but without particle-hole symmetry, and interacting topological insulators with spin-flip terms.

[Role and clinical significance of Th17/Treg balance in patients with severe exacerbation of hepatitis B].

OBJECTIVE: To investigate the role of Th17/Treg balance in immune mechanism in severe exacerbation of hepatitis B. METHODS: The clinical data of 41 patients with chronic hepatitis B were collected, and according to the conditions during hospitalization, these patients were divided into exacerbation group (19 patients) and improvement group (22 patients). On admission, at weeks 1 and 2 of treatment, and at the end of treatment, flow cytometry was used to measure the frequencies of Th17 and Treg cells in peripheral blood, and enzyme-linked immunosorbent assay was used to determine the serum levels of interleukin-17 (IL-17), interleukin-10 (IL-10), and transforming growth factor-ß (TGF-ß). The dynamic changes in the frequencies of Th17 and Treg cells were compared between the two groups, and the correlation between clinical indices for hepatitis and cytokines was analyzed. The t-test was used for comparison between groups, a one-way analysis of variance was used for comparison within one group across different time points, and Pearson correlation analysis was performed. RESULTS: With disease progression, the exacerbation group showed an increase in the frequency of Th17 cells and a relatively low frequency of Treg cells; compared with the improvement group, the exacerbation group had a higher frequency of Th17 cells and a lower frequency of Treg cells. Th17/Treg ratio gradually increased with exacerbation and decreased with improvement in conditions; in the exacerbation group and the improvement group, Th17/Treg ratio was positively correlated with total bilirubin and negatively correlated with prothrombin activity. In the exacerbation group and the improvement group, Th17 cells were positively correlated with IL-17, and Treg cells were positively correlated with IL-10 and TGF-ß. CONCLUSION: Th17 and Treg cells play important roles in severe exacerbation of hepatitis B, and Th17/Treg ratio may be used as an immunobiological marker for the judgment of severity during severe exacerbation of hepatitis B.

[Icariin reduces S-nitrosogultathione induced endothelial cell apoptosis through modulating AKT/P53 pathway].

OBJECTIVE: To observe the effects of icariin on S-nitrosogultathione(GSNO) induced endothelial cell apoptosis, and to explore the relative mechanisms. METHODS: EA.hy926 cell line was provided by Zhejiang University and cells were divided into blank control group, GSNO group (1 mmol/L GSNO), icariin (ICA) intervention group (GSNO+ different concentrations (high, medium and low: 10, 1 and 0.1 µmol/L ICA) and 1 µmol/L LY294002 pretreatment groups (AKT protease pathway inhibitor on top of ICA groups) by cluster random sample method. After 48 hours. EA.hy 926 cell survival was detected by thiazolyl blue tetrazolium bromicle (MTT) method. Lactate dehydrogenase (LDH) activity, malonaldehyde (MDA) content, reactive oxygen species (ROS) level, mitochondrial membrane potential were also measured. The protein expression of protein kinase B(AKT)/phosphorylation protein kinase B(p-AKT), people tumor-suppressor protein (protein 53, P53), cytochrome C (CYC), endothelial nitric oxide synthetase (eNOS)/phosphorylation endothelial nitric oxide synthetase (p-eNOS), procaspase-3/caspase-3 was detected by Western blot. RESULTS: (1) The cell survival rate was significantly lower in GSNO group than in the blank control group (P< 0.01), which was significantly higher in the high, medium and low concentration ICA groups than in the GSNO group (all P< 0.01). (2) The LDH activity was significantly higher in the GSNO group than in the blank control group ((142.65±5.56) U/L vs. (50.01±3.42) U/L, P< 0.05), which was significantly reduced by high, medium and low concentration ICA ((98.02±3.52), (105.29±6.89) and (117.16±4.27) U/L vs. (142.65±5.56) U/L, all P< 0.05) in a dose-dependent manner. (3) The MDA content was significantly higher in GSNO group than in the blank control group ((11.14±0.37) nmol/mg vs. (5.21±0.18) nmol/mg, P< 0.05), which could be reduced by pretreatment with high, medium and low concentration ICA ((6.60±0.41), (6.83±0.21) and (8.29±0.07) nmol/mg vs. (11.14 ±0.37) nmol/mg, all P< 0.05). (4) The ROS content was significantly higher in GSNO group than in the blank control group ((173.15±11.12)% (relative ratio to the blank control group), P< 0.05), which could be significantly reduced by pretreatment with high, medium and low concentration ICA ((122.56±8.09)%, (134.52±9.09)%, and(149.89±9.16)% (the ratio of the above are compared with the blank control group), P< 0.05). (5) The mitochondrial membrane potential was significantly higher in the GSNO group (0.84 ± 0.04) than in the blank control group (0.12 ±0.12), which could be significantly reduced by pretreatment with high, medium and low concentration ICA ((0.57±0.08), (0.63±0.02), (0.66±0.04) vs. (0.84±0.04), all P<0.05). (6) The expression of AKT/p-AKT was significantly lower in GSNO group than in the blank control group (P< 0.05), which could be significantly upregulated by pretreatment with high, medium and low concentration ICA in a concentration-dependent manner, above effects could be blocked by LY294002 (all P<0.05). (7) The expression of P53 was significantly higher in GSNO group than in the blank control group (P< 0.05), which could be significantly down regulated by pretreatment with high, medium and low concentration ICA in a concentration-dependent manner, above effects could be blocked by LY294002(all P<0.05). (8) The expression of CYC and caspase-3 was significantly reduced in the mitochondria and increased in cytoplasm post GSNO treatment compared to blank control group, which could be reversed by pretreatment with high, medium and low concentration ICA(all P<0.05). (9) The expression of eNOS/p-eNOS was similar between GSNO and the blank control group, while it was significantly upregulated by pretreatment with high, medium and low concentration ICA and this effect could be blocked by LY294002(all P<0.05). CONCLUSION: Icariin could reduce GSNO induced endothelial cell apoptosis through activating AKT pathway and downregulating P53 activity.

First molecular characterization of Giardia duodenalis from goats in Malaysia.

In the present study, 310 faecal samples from goats from eight different farms in Malaysia were tested for the presence of Giardia using a PCR-coupled approach. The nested PCR for SSU amplified products of the expected size (∼200 bp) from 21 of 310 (6.8%) samples. Sixteen of these 21 products could be sequenced successfully and represented six distinct sequence types. Phylogenetic analysis of the SSU sequence data using Bayesian Inference (BI) identified Giardia assemblages A, B and E. The identification of the 'zoonotic' assemblages A and B suggests that Giardia-infected goats represent a possible reservoir for human giardiasis in Malaysia.

Laparoscopic radical resection for rectal cancer in a patient with uncorrected truncus arteriosus type IV: A case report.

Persistent truncus arteriosus is a rare congenital heart malformation which if not corrected, results in the death of about 50% of the patients, while fewer than 20% of the patients survive the first year of life. Here, we report the successful anesthetic management of an adult patient with uncorrected truncus arteriosus who presented for the laparoscopic radical resection of rectal cancer.

Generation of pancreatic insulin-producing cells from rhesus monkey induced pluripotent stem cells.

AIMS/HYPOTHESIS: The generation of induced pluripotent stem cells (iPSCs) provides a promising possibility for type 1 diabetes therapy. However, the generation of insulin-producing cells from iPSCs and evaluation of their efficacy and safety should be achieved in large animals before clinically applying iPSC-derived cells in humans. Here we try to generate insulin-producing cells from rhesus monkey (RM) iPSCs. METHODS: Based on the knowledge of embryonic pancreatic development, we developed a four-stage protocol to generate insulin-producing cells from RM iPSCs. We established a quantitative method using flow cytometry to analyse the differentiation efficiency. In addition, to evaluate the differentiation competence and function of RM iPSC-derived cells, transplantation of stage 3 and 4 cells into immunodeficient mice was performed. RESULTS: RM iPSCs were sequentially induced to definitive endoderm (DE), pancreatic progenitors (PP), endocrine precursors (EP) and insulin-producing cells. PDX1(+) PP cells were obtained efficiently from RM iPSCs (over 85% efficiency). The TGF-ß inhibitor SB431542 promoted the generation of NGN3(+) EP cells, which can generate insulin-producing cells in vivo upon transplantation. Finally, after this four-stage differentiation in vitro, insulin-producing cells that could secrete insulin in response to glucose stimulation were obtained. When transplanted into mouse models for diabetes, these insulin-producing cells could decrease blood glucose levels in approximately 50% of the mice. CONCLUSIONS/INTERPRETATION: We demonstrate for the first time that RM iPSCs can be differentiated into functional insulin-producing cells, which will provide the basis for investigating the efficacy and safety of autologous iPSC-derived insulin-producing cells in a rhesus monkey model for type 1 diabetes therapy.

Partial order and finite-temperature phase transitions in Potts models on irregular lattices.

We evaluate the thermodynamic properties of the 4-state antiferromagnetic Potts model on the Union-Jack lattice using tensor-based numerical methods. We present strong evidence for a previously unknown, "entropy-driven," finite-temperature phase transition to a partially ordered state. From the thermodynamics of Potts models on the diced and centered diced lattices, we propose that finite-temperature transitions and partially ordered states are ubiquitous on irregular lattices.

Generation of mammalian cell lines with gene knock-down for human MCHR2.

Appetite regulating neuropeptide melanin-concentrating hormone (MCH) has been implicated in obesity. It functions through its two receptors MCHR1 and MCHR2. While MCH and MCHR1 have been studied more extensively, the function of MCHR2 remains largely unknown, due to the lack of suitable in vitro and in vivo models. To create an in vitro system of genetic knock-down of MCHR2 in mammalian cells, we constructed four small hairpin RNAs (shRNAs) against human MCHR2 in eukaryotic expression vector, and transfected the plasmids into CHO cells that stably express human MCHR2. Using the empty vector or a negative shRNA control plasmid, we show that MCHR2-shRNAs suppressed 45.8% - 66.4% of MCHR2 expression at both mRNA and protein levels. As the result, in cells carrying the MCHR2-shRNAs, binding of MCHR2 to MCH was decreased by 39.4% - 78.7% accompanied by a similar decrease in affinity of the receptor to ligand by 40.9% - 81.9%. These cells still respond to MCH treatment, but intracellular Ca2+ release as the downstream signaling event was also decreased by 114.8% - 822.4%. Together, this study generated a set of shRNAs and cell lines as valuable reagents for further study on MCHR2 functions. These results will ultimately help to advance our knowledge about appetite regulating neuropeptide receptors.

Reduced long non-coding RNA PTENP1 contributed to proliferation and invasion via miR-19b/MTUS1 axis in patients with cervical cancer.

OBJECTIVE: Many studies showed that long non-coding RNAs (lncRNAs) may serve as prospective markers for patients with malignant cancers, including cervical cancer (CC). In this study, we mainly investigate the functions of lncRNA PTENP1 in the progression of human CC. MATERIALS AND METHODS: Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was performed to detect expression levels of PTENP1, miR-19b and MTUS1 in CC tissues, the adjacent tissues and CC cell lines. The correlations between PTENP1 with miR-19b, miR-19b with MTUS1 and PTENP1 with MTUS1 were analyzed. Overall survival (OS) of patients was analyzed using Kaplan-Meier method. Proliferation capacity was measured by CCK-8 assay and the invasion ability in CC cell line was detected by transwell assay. Western blot (WB) assay was performed to measure protein levels of tissues and CC cell lines. Finally, Dual-Luciferase reporter assay was performed to prove the potential binding sites between PTENP1 and miR-19b, miR-19b and MTUS1. RESULTS: We found that PTENP1 was reduced in CC tissues and CC cell lines, which predicted the poor diagnosis of CC patients. MiR-19b was increased in CC tissues, which was negatively correlated with PTENP1 in CC tissues. MTUS1 was reduced in CC tissues, which was negatively correlated with miR-19b and positively correlated within PTENP1 CC tissues. Furthermore, PTENP1 overexpression inhibited cell proliferation ability and invasion capacity in HeLa cells, as well as repressed expressions of Cyclin D1, N-cadherin, and Vimentin. Moreover, Luciferase gene reporter assays verified that miR-19b was a direct target miRNA of PTENP1, and MTUS1 was identified as a direct target of miR-19b. In addition, the inhibited cell proliferation and invasion abilities in HeLa cells with p-PTENP1 were eliminated following with miR-19b mimic transfection. CONCLUSIONS: According to the results, this study showed that PTENP1 was reduced in CC patients and it was a prognostic factor for CC patients. Furthermore, we firstly uncovered that PTENP1 could inhibit cell proliferation and invasion via miR-19b/MTUS1 in CC patients, which uncovered the tumor-suppressive role of PTENP1 in CC and suggested that it might be a potential target for treating human CC.

Critical properties of the two-dimensional q-state clock model.

We perform the state-of-the-art tensor network simulations directly in the thermodynamic limit to clarify the critical properties of the q-state clock model on the square lattice. We determine accurately the two phase transition temperatures through the singularity of the classical analog of the entanglement entropy, and provide extensive numerical evidences to show that both transitions are of the Berezinskii-Kosterlitz-Thouless (BKT) type for q≥5 and that the low-energy physics of this model is well described by the Z_{q}-deformed sine-Gordon theory. We also determine the characteristic conformal parameters, especially the compactification radius, that govern the critical properties of the intermediate BKT phase.

Second renormalization of tensor-network states.

We propose a second renormalization group method to handle the tensor-network states or models. This method dramatically reduces the truncation error of the tensor renormalization group. It allows physical quantities of classical tensor-network models or tensor-network ground states of quantum systems to be accurately and efficiently determined.

A quantum transfer matrix method for one-dimensional disordered electronic systems.

We develop a novel quantum transfer matrix method to study thermodynamic properties of one-dimensional (1D) disordered electronic systems. It is shown that the partition function can be expressed as a product of 2 × 2 local transfer matrices. We demonstrate this method by applying it to the 1D disordered Anderson model. Thermodynamic quantities of this model are calculated and discussed.

A sensitive and efficient detection method for bovine viral diarrhea virus (BVDV) in single preimplantation bovine embryos.

The objective was to develop a method to accurately and efficiently detect minute amounts of bovine viral diarrhea virus (BVDV) associated with a single embryo. There are two major challenges for BVDV detection in a single embryo: the test sensitivity and the efficiency of viral molecule recovery. These become even more critical when attempts are made to detect BVDV infections that occurred naturally, not through artificial exposure of the embryos to high affinity BVDV strains. We have developed a one-step sample preparation method that has increased the viral molecule recovery rate compared to the standard RNA isolation procedure by 7-100-fold. Instead of using the traditional virus exposure approach, we generated BVDV positive embryos via somatic cell nuclear transfer (SCNT) technology using BVDV positive donor cells. By combining the highly efficient sample preparation procedure with a sensitive one-step, real-time PCR system, we have developed a sensitive test that allows detection of as low as two copies of BVDV in a single embryo. This method will allow systematic risk assessment for BVDV transmission during in vitro embryo production via IVF or SCNT procedures.