Unconventional room-temperature negative magnetoresistance effect in Au/n-Ge:Sb/Au devices

Non-magnetic semiconductor materials and their devices have attracted wide attention since they are usually prone to exhibit large positive magnetoresistance(MR)effect in a low static magnetic field environment at room temperature.However,how to obtain a large room-temperature negative MR effect in them remains to be studied.In this paper,by designing an Au/n-Ge:Sb/Au device with metal electrodes located on identical side,we observe an obvious room-temperature negative MR effect in a specific 50 T pulsed high magnetic field direction environment,but not in a static low magnetic field environment.Through the analysis of the experimental measurement of the Hall effect results and bipolar transport theory,we propose that this unconventional negative MR effect is mainly related to the charge accumulation on the surface of the device under the modulation of the stronger Lorentz force provided by the pulsed high magnetic field.This theoretical analytical model is further confirmed by regulating the geometry size of the device.Our work sheds light on the development of novel magnetic sensing,magnetic logic and other devices based on non-magnetic semiconductors operating in pulsed high magnetic field environment.

Narcotrend监测下全身麻醉对机体应激反应的影响

目的探究Narcotrend监测下全身麻醉在直肠癌根治术快速康复外科中对机体应激反应的影响。方法选取60例采取快速康复外科治疗方案的择期行腹腔镜直肠癌根治术(Dixon)的患者,随机分为两组:N组术中用Narcotrend监测调控麻醉深度,D组为对照组,术中凭血压、心率和临床体征等经验调控麻醉深度,每组30例,麻醉维持采用丙泊酚和瑞芬太尼持续输注,于两组麻醉前(T_0)、麻醉中(T1)即术中30 min、麻醉后(T_2)即出麻醉恢复室时和术后24 h(T_3)采集静脉血测定血清C反应蛋白(CRP)、白细胞介素6(IL-6)和皮质醇(Cor)的水平,且以术后10 min内达到拔管标准顺利拔除气管导管者为快通道麻醉实施成功,观察两组患者快通道麻醉的成功例数和苏醒期躁动发生例数。结果 D组的CRP在T1～3高于T0和N组(P <0.05),D组的IL-6和Cor在T_2和T_3高于T0和N组(P <0.05);N组快通道麻醉的成功率高于D组(P <0.05);N组苏醒期躁动发生率低于D组(P <0.05)。结论 Narcotrend监测下的全身麻醉在直肠癌根治快速康复外科中能有效降低机体的应激反应,有效达到快通道麻醉,两者均符合快速康复外科理念的目标。

Role of cancer-associated fibroblasts in invasion and metastasis of gastric cancer

Cancer-associated fibroblasts(CAFs) are important components of various types of tumors,including gastric cancer(GC).During tumorigenesis and progression,CAFs play critical roles in tumor invasion and metastasis via a series of functions including extracellular matrix deposition,angiogenesis,metabolism reprogramming and chemoresistance.However,the mechanism of the interaction between gastric cancer cells and CAFs remains largely unknown.Micro RNAs(mi RNAs) are a class of non-coding small RNA molecules,and their expression in CAFs not only regulates the expression of a number of target genes but also plays an essential role in the communication between tumor cells and CAFs.In this review,we provide an overview of recent studies on CAF mi RNAs in GC and the relevant signaling pathways in gastrointestinal tumors.Focusing the attention on these signaling pathways may help us better understand their role in tumor invasion and metastasis and identify new molecular targets for therapeutic strategies.

Optimization of flow control devices in a single-strand slab continuous casting tundish

The optimization of flow control devices in a single-slab continuous casting tundish was carried out by physical modeling, and the optimized scheme was presented. With the optimal tundish configuration, the minimum residence time of liquid steel was increased by 1.4 times, the peak concentration time was increased by 97%, and the dead volume fraction was decreased by 72%. A mathematical model for molten steel in the tundish was established by using the fluid dynamics package Fluent. The velocity field, concentration field, and the resi-dence time distribution （RTD） curves of molten steel flow before and after optimization were obtained. Experimental results showed that the reasonable configuration with flow control devices can improve the fluid flow characteristics in the tundish. The results of industrial applica-tion show that the nonmetallic inclusion area ratio in casting slabs is decreased by 32% with the optimal tundish configuration.

Sofosbuvir and ABT-450: Terminator of hepatitis C virus?

Combination therapy with peginterferon (pegIFN)-α and ribavirin (RBV) has been the standard of care (SOC) for chronic hepatitis C. Unfortunately, not all patients can achieve a sustained virologic response (SVR) with this regimen. SVR rates are approximately 80% in patients with hepatitis C virus (HCV) genotype 2, 3, 5 and 6 and 40%-50% in patients with genotype 1 and 4. Therefore, strategies to improve SVR rates have been an important issue for clinical physicians. Several direct acting antiviral agents (DAAs) have significantly higher SVR rates when combined with pegIFN-α and RBV than pegIFN-α and RBV alone. Treatments containing DAAs have several advantages over the previous SOC, including higher specificity and efficacy, shorter treatment durations, fewer side effects, and oral administration. Based on these advantages, treatment with pegIFN-α and RBV plus telaprevir or boceprevir has become the current SOC for patients with genotype 1 HCV infection. However, many patients are either not eligible for therapy or decline treatment due to coexisting relative or absolute contraindications as well as an inability to tolerate the hematological side effects and adverse events caused by the new SOC. These factors have contributed to the advent of pegIFN-α-free regimens. The newest therapeutic regimens containing sofosbuvir and ABT-450 have shown promising results. In this review, we summarize the development of anti-HCV agents and the clinical efficacy of sofosbuvir and ABT-450-based therapies as well as the potential for future HCV studies.

Primary biliary cirrhosis-associated hepatocellular carcinoma in Chinese patients:Incidence and risk factors

AIM: To investigate the incidence, characteristics, and risk factors for hepatocellular carcinoma(HCC) in Chinese patients with primary biliary cirrhosis(PBC).METHODS: We reviewed the data of 52 PB Cassociated HCC patients treated at Beijing 302 Hospital from January 2002 to December 2013 and analyzed its incidence and characteristics between the two genders. The risk factors for PBC-associated HCC were analyzed via a case-control study comprising 20 PBC patients with HCC and 77 matched controls without HCC. The matched factors included gender, age, follow-up period and Child-Pugh scores. Conditional logistic regression was used to evaluate the odds ratios of potential risk factors for HCC development. A P < 0.05 was considered statistically significant. RESULTS: The incidence of HCC in Chinese PBC patients was 4.13%(52/1255) and was significantly higher in the males(9.52%) than in the females(3.31%). Among the 52 PBC patients with HCC, 55.76%(29/52) were diagnosed with HCC and PBC simultaneously, and 5.76%(3/52) were diagnosed with HCC before PBC. The males with PBC-associated HCCwere more likely than the females to have undergone blood transfusion(18.75% vs 8.33%, P = 0.043), consumed alcohol(31.25% vs 8.33%, P = 0.010), smoked(31.25% vs 8.33%, P = 0.010), had a family history of malignancy(25% vs 5.56%, P = 0.012), and had serious liver inflammation, as indicated by the elevated levels of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and γ-glutamyl transpeptidase(P < 0.05). Conditional logistic regression analysis revealed that body mass index(BMI) ≥ 25 [adjusted odds ratio(AOR) = 1.116, 95%CI: 1.002-1.244, P = 0.045] and history of alcohol intake(AOR = 10.294, 95%CI: 1.108-95.680, P = 0.040) were significantly associated with increased odds of HCC development in PBC patients. CONCLUSION: HCC is not rare in Chinese PBC patients. Risk factors for PBC-associated HCC include BMI ≥ 25 and a history of alcohol intake. In addition to regular monitoring, PBC patients may benefit from abstinence from alcohol and body weight control.

Expression and location of Smad2,4 mRNAs during and after liver fibrogenesis of rats

AIM： To investigate the location alteration of Smad2 and Smad4 mRNAs in the liver during and after fibrogenesis in rats. METHODS： Eighty male Wistar rats weighing approximately 200 g each were used. The rat models of experimental hepatic fibrosis were established by injection with carbon tetrachloride （CCh）, normal rats and rats were injected with olive oil and served as control groups. In situ hybridization（ISH） was used to detect the Smad2 and Smad4 mRNA in liver. RESULTS： In situ hybridization showed Smad2 and Smad4 mRNA expressions in the cytoplasm of hepatic stellate cells （HSC）, fibroblasts and myofibroblasts around the central vein and hepatic sinus during and after fibrogenesis. Expression of Smad2, 4 mRNA was higher than that in normal and control rats. CONCLUSION： In the process of and after hepatic fibrosis formation, HSC, fibroblasts and myofibroblasts are the major cells that express Smad2 and Smad4. The more serious the hepatic fibrosis is in the injured liver, the higher the level of Smad2 and Smad4 gene expression is during and after fibrogenesis respectively.

Phase Ⅰ clinical study of personalized peptide vaccination combined with radiotherapy for advanced hepatocellular carcinoma

AIM To assess the efficacy and safety of a new treatment modality, cellular immune therapy based on personalized peptide vaccination(PPV-DC-CTL) combined with radiotherapy, for treating advanced hepatocellular carcinoma(HCC). METHODS A total of nine patients with advanced HCC were enrolled. Multidisciplinary consultation confirmed that all the patients definitely had no opportunity of surgery, because four patients had multiple liver metastases(the number of liver lesions > 3), one patient had liver metastases and portal vein tumor thrombosis, one patient had lung and bone metastases, two patients had liver and lung metastases and one patient had liver metastasis and peritoneal metastasis. Patients with metastasis were treated with precise radiotherapy combined with PPV-DC-CTL.RESULTS Following radiotherapy and one to three cycles of PPV-DC-CTL treatment, AFP levels were significantly decreased in six patients and imaging assessment of the lesions showed a partial response(PR) in three patients and stable disease in the other three patients. The response rate was 33% and disease control rate was 66%. This regimen was found to be safe and well tolerated. None of the patients developed liver or kidney side effects. Only one patient developed grade Ⅱ bone marrow suppression and the remaining patients had no significant hematological side effects.CONCLUSION Radiotherapy combined with PPV-DC-CTL provides a new therapeutic strategy for patients with advanced HCC, which is well tolerated, safe, feasible and effective.

Recent advances in the effects of microwave radiation on brains

This study concerns the effects of microwave on health because they pervade diverse fields of our lives. The brain has been recognized as one of the organs that is most vulnerable to microwave radiation. Therefore, in this article, we reviewed recent studies that have explored the effects of microwave radiation on the brain, especially the hippocampus, including analyses of epidemiology, morphology, electroencephalograms, learning and memory abilities and the mechanisms underlying brain dysfunction. However, the problem with these studies is that different parameters, such as the frequency, modulation, and power density of the radiation and the irradiation time, were used to evaluate microwave radiation between studies. As a result, the existing data exhibit poor reproducibility and comparability. To determine the specific dose-effect relationship between microwave radiation and its biological effects, more intensive studies must be performed.

Novel CDH1 germline mutations identified in Chinese gastric cancer patients

AIM:To give a comprehensive report of E-cadheringene (CDH1) variations in a population at a high risk for gastric cancer (GC).METHODS:The samples consisted of 178 men and 58 women with a mean age of 62.3 ± 9.4 years and an age range of 30-84 years.A total of 240 cancerfree controls were recruited (mean age of 61.8 ± 10.1 years,age range of 26-82 years).Samples were screened for CDH1 germline mutations by high-resolution melting analysis or directly sequencing.Luciferase reporter assay,RNA splicing assay and bioinformatic analysis were used to evaluate the effect of mutations.RESULTS:Four novel CDH1 sequence alterations were identified in GC patients including a G>T transition 49 bp before the start codon;a three-nucleotide deletion,c.44_46del TGC;one missense mutation,c.604G>A (V202I);and one variation in the intron,c.1320+7A>G.In addition,polymorphism frequencies were observed for CDH1-164delT,-161C>A,-73A>C,c.48+6C>T,c.48+62_48+63delinsCGTGCCCCAGCCC,c.894C>T (A298A),c.1224G>A (A408A),c.1888C>G (L630V),c.2076T>C (A692A),and c.2253C>T (N751N) which is similar to the data reported in http://www.ncbi.nlm.nih.gov/projects/SNP/.RNA splicing analysis suggested that the c.1320+7A>G and c.1224G>A variations did not affect exon splicing ability.Luciferase reporter assay demonstrated that the c.-49T variation might be helpful for E-cadherin transcription,though the increase in transcription activity is limited (only 33%).SIFT score and PolyPhen analysis both demonstrated that the L630V missense mutation probably damages protein function,while the V202I variant does not.CONCLUSION:This study reveals novel mutations in sporadic GC patients which had been poorly investigated for susceptibility genes.

Hydroxylated graphene quantum dots as fluorescent probes for sensitive detection of metal ions

Highly sensitive methods are important for monitoring the concentration of metal ions in industrial wastewater.Here,we developed a new probe for the determination of metal ions by fluorescence quenching.The probe consists of hydroxylated graphene quantum dots(H-GQDs),prepared from GQDs by electrochemical method followed by surface hydroxylation.It is a non-reactive indicator with high sensitivity and detection limits of 0.01μM for Cu2+,0.005μM for Al3+,0.04μM for Fe3+,and 0.02μM for Cr3+.In addition,the low biotoxicity and excellent solubility of H-GQDs make them promising for application in wastewater metal ion detection.

Common mtDNA variations at C5178a and A249d/T6392C/G10310A decrease the risk of severe COVID-19 in a Han Chinese population from Central China

Background:Mitochondria have been shown to play vital roles during severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection and coronavirus disease 2019(COVID-19)development.Currently,it is unclear whether mitochondrial DNA(mtDNA)variants,which define mtDNA haplogroups and determine oxidative phosphorylation performance and reactive oxygen species production,are associated with COVID-19 risk.Methods:A population-based case-control study was conducted to compare the distribution of mtDNA variations defining mtDNA haplogroups between healthy controls(n=615)and COVID-19 patients(n=536).COVID-19 patients were diagnosed based on molecular diagnostics of the viral genome by qPCR and chest X-ray or computed tomography scanning.The exclusion criteria for the healthy controls were any history of disease in the month preceding the study assessment.MtDNA variants defining mtDNA haplogroups were identified by PCR-RFLPs and HVS-I sequencing and determined based on mtDNA phylogenetic analysis using Mitomap Phylogeny.Student’s t-test was used for continuous variables,and Pearson’s chi-squared test or Fisher’s exact test was used for categorical variables.To assess the independent effect of each mtDNA variant defining mtDNA haplogroups,multivariate logistic regression analyses were performed to calculate the odds ratios(OR)and 95%confidence intervals(CI)with adjustments for possible confounding factors of age,sex,smoking and diseases(including cardiopulmonary diseases,diabetes,obesity and hypertension)as determined through clinical and radiographic examinations.Results:Multivariate logistic regression analyses revealed that the most common investigated mtDNA variations(>10%in the control population)at C5178 a(in NADH dehydrogenase subunit 2 gene,ND2)and A249 d(in the displacement loop region,D-loop)/T6392 C(in cytochrome c oxidase I gene,CO1)/G10310 A(in ND3)were associated with a reduced risk of severe COVID-19(OR=0.590,95%CI 0.428–0.814,P=0.001;and OR=0.654,95%CI 0.457–0.936,P=0.020,respectively),while A4833 G(ND2),A4715 G(ND2),T3394 C(ND1)and G5417 A(ND2)/C16257 a(D-loop)/C16261 T(D-loop)were related to an increased risk of severe COVID-19(OR=2.336,95%CI 1.179–4.608,P=0.015;OR=2.033,95%CI 1.242–3.322,P=0.005;OR=3.040,95%CI 1.522–6.061,P=0.002;and OR=2.890,95%CI 1.199–6.993,P=0.018,respectively).Conclusions:This is the first study to explore the association of mtDNA variants with individual’s risk of developing severe COVID-19.Based on the case–control study,we concluded that the common mtDNA variants at C5178 a and A249 d/T6392 C/G10310 A might contribute to an individual’s resistance to developing severe COVID-19,whereas A4833 G,A4715 G,T3394 C and G5417 A/C16257 a/C16261 T might increase an individual’s risk of developing severe COVID-19.

Curing reaction and mechanism of phenol-formaldehyde novolac resins for foundry

In this study on the curing dynamics of phenol-formaldehyde novolac resins(PFNR) and hexamethylene tetramine(HMTA), two typical commercial PFNR were selected as examples and the curing reactions of the resins with HMTA were studied by differential scanning calorimetry(DSC). Based on the data calculated by the Kissinger equation and the Crane equation, a thermocuring dynamic model was established, from which the process conditions, activation energy, reaction kinetics equation and a f irst-order reaction of the curing reactions were derived.

Phase Effects of Long-Wavelength Rayleigh–Taylor Instability on the Thin Shell

Taking the long-wavelength Rayleigh-Taylor instability(RTI) on the thin shell of inertial confinement fusion as the research object,a linear analytical model is presented to study the phase effects that are caused by the phase difference of single-mode perturbations on the two interfaces.Its accuracy is tested by numerical simulations.By analyzing the characteristic of this model,it is found that the phase difference does not change the basic RTI structure(only one spike and one bubble in a period).However,the symmetry of the spike and bubble is destroyed,which has non-expected influences on the convergent motion of ICF targets.Meanwhile,the phenomenon that the distance between spikes and bubbles along the vertical direction of acceleration differs by π is demonstrated.It is also shown that when the phase difference is large,the temporal evolution of the RTI is more serious and the thin target is easier to tend to break.

A survey of knowledge about hepatitis B among new military recruits in China

Background: Hepatitis B is a disease that affects the liver and is caused by the hepatitis B virus(HBV). Hepatitis B is a serious public health problem in China. The objective of this study was to assess knowledge of and behaviours towards the transmission and prevention of hepatitis B of new military recruits in China.Methods: A cross-sectional study was conducted among 800 new military recruits. A self-administered, structured questionnaire was used to collect information, and 727 questionnaires were returned completed. Analysis was performed using SPSS 18.0, and P<0.05 was considered statistically significant.Results: Of the respondents, 665(91.5%) were male and 62(8.5%) were female. The mean age was 18.9±1.7 years. A total of 608 respondents(83.6%) demonstrated poor knowledge and 119(16.4%) adequate knowledge about HBV. Older age, female and higher education level were statistically associated with a higher mean knowledge score. Multivariate logistic regression showed that age(OR=3.040, 95%CI 1.724–5.359, P<0.001) and gender(OR=1.791, 95%CI 1.325–2.421, P<0.001) were significantly associated with appropriate behavioural practices towards prevention of HBV.Conclusion: Against a backdrop of high HBV prevalence in China, new military recruits had poor knowledge of HBV. New recruits need better education about HBV to assist in reducing and preventing HBV infection.

Weakly Nonlinear Rayleigh–Taylor Instability in Cylindrically Convergent Geometry

The Rayleigh–Taylor instability（RTI） in cylindrical geometry is investigated analytically through a second-order weakly nonlinear（WN） theory considering the Bell–Plesset（BP） effect. The governing equations for the combined perturbation growth are derived. The WN solutions for an exponentially convergent cylinder are obtained. It is found that the BP and RTI growths are strongly coupled, which results in the bubble-spike asymmetric structure in the WN stage. The large Atwood number leads to the large deformation of the convergent interface. The amplitude of the spike grows faster than that of the bubble especially for large mode number m and large Atwood number A. The averaged interface radius is small for large mode number perturbation due to the mode-coupling effect.

Nasal metastases from neuroblastoma-a rare entity:Two case reports

BACKGROUND Neuroblastoma(NB)is one of the most common malignancies in children.Metastasis in NB is not uncommon.However,nasal metastases are rare.Here,we reported two pediatric cases of nasal metastases.CASE SUMMARY Case 1 was a 3-year-old boy without a history of NB.Case 2 was a 10-year-old girl who had a history of NB for 6 years.Both of them presented with symptoms of nasal and sinus masses such as epistaxis or discharge from the nose.The radiologic imaging results revealed masses in the nasal cavity or nasopharynx in both cases and a mass in the right adrenal gland of case 1.The pathologic examination of biopsy samples of their nasal masses revealed“small round bluecell tumor”along with abundant vascular fibrous septa.The tumor cells expressed synaptophysin,cluster of differentiation 56,chromogranin A,paired like homeobox protein 2B and a very high Ki67 index in both case but were negative for vimentin,desmin,leucocyte common antigen and cytokeratin.Myelocytomatosis viral related oncogene,neuroblastoma derived(MYCN)amplification was detected in both cases.Finally,the two cases were diagnosed as nasal metastases from NB based on the clinical and pathologic findings.The two patients affected by NB were>18 mo old,the primary tumor location was adrenal gland,and they presented with multiple metastases.CONCLUSION It is difficult to differentiate between metastatic NB in the nose and olfactory neuroblastoma in the absence of a history of NB.Paired like homeobox protein 2B can play an important role in the diagnosis and differential diagnosis of this disease.

Simulation of the Weakly Nonlinear Rayleigh–Taylor Instability in Spherical Geometry

The Rayleigh-Taylor instability at the weakly nonlinear(WN)stage in spherical geometry is studied by numerical simulation.The mode coupling processes are revealed.The results are consistent with the WN model based on parameter expansion,while higher order effects are found to be non-negligible.For Legendre mode perturbation Pn(cos B),the nonlinear saturation amplitude(NSA)of the fundamental mode decreases with the mode number n.When n is large,the spherical NSA is lower than the corresponding planar one.However,for large n,the planar NSA can be recovered by applying Fourier transformation to the bubble/spike near the equator and calculating the NSA of the converted trigonometric harmonic.

Interface Width Effect on the Weakly Nonlinear Rayleigh–Taylor Instability in Spherical Geometry

Interface width effect on the spherical Rayleigh–Taylor instability in the weakly nonlinear regime is studied by numerical simulations.For Legendre perturbation mode Pn with wave number Kn and interface half-width L,the commonly adopted empirical linear growth rate formulaγnem(L)=γn/√1+KnL is found to be sufficient in spherical geometry.At the weakly nonlinear stage,the interface width affects the mode coupling processes.The development of the mode P2n is substantially influenced by the interface width.Moreover,the nonlinear saturation amplitude increases with the interface width.

Coupling between velocity and interface perturbations in cylindrical Rayleigh–Taylor instability

Rayleigh–Taylor instability(RTI)in cylindrical geometry initiated by velocity and interface perturbations is investigated analytically through a third-order weakly nonlinear(WN)model.When the initial velocity perturbation is comparable to the interface perturbation,the coupling between them plays a significant role.The difference between the RTI growth initiated only by a velocity perturbation and that only by an interface perturbation in the WN stage is negligibly small.The effects of the mode number on the first three harmonics are discussed respectively.The low-mode number perturbation leads to large amplitudes of RTI growth.The Atwood number and initial perturbation dependencies of the nonlinear saturation amplitude of the fundamental mode are analyzed clearly.When the mode number of the perturbation is large enough,the WN results in planar geometry are recovered.