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With critical lessons drawn from past major earthquakes, the engineering community is appealing for a fundamental shift in the existing design philosophy for structures in seismic zones. One strategy is to endow structures with self-centering (SC) capability. While the concept of SC structures is not new, many novel technologies have been recently emerging that are more efficient, compact, and cost-effective; on the other hand, growing controversy and dispute have also been appearing with deepening investigations. This paper presents a critical review of the evolution of SC technologies and systems for both researchers and practitioners, with an emphasis on post-tension (PT), high-performance spring, and shape memory alloy (SMA) strategies. These SC technologies, together with various energy dissipation options, form the basis of a large part of the newly proposed SC philosophies. This review also includes typical SC structural members such as beam-to-column connections, braces, dampers, shear walls, bridge piers, and isolation bearings, followed by a discussion on the dynamic behavior from a system-level point of view. Available design approaches for SC structures are also touched upon, and practical applications that have emerged over the past decades in several countries including Canada, China, New Zealand, and the US are presented. This paper concludes with an executive summary that covers technological advances, knowledge gaps, and future research directions. [ABSTRACT FROM AUTHOR]

A novel shape memory alloy wires-based smart roller bearing (SMA-RBs) has been developed and its cyclic behavior under reverse cyclic loadings has been experimentally investigated. However, its efficacy and performance in enhancing the seismic performance of bridge structures have not been well understood and proven. A new self-centering hysteresis model for SMA-RBs has been proposed to properly simulate their hysteretic behavior, which has been experimentally validated through a pseudo-static test. A methodology is proposed to determine the four damage states of SMA-RB (i.e. slight, moderate, extensive, and collapse) considering the contribution of SMA wires. The smart SMA-RBs are utilized for a cable-stayed bridge in China. The vulnerability of two reference bridges, i.e. the floating system (FS) and rigid system (RS), and one isolated bridge equipped with SMA-RBs (SMA-RBS) are compared at component and system levels. The applicability of three commonly used intensity measures (IMs), i.e. PGA, PGV, and Sa(T1), are evaluated and PGV turns out to be the optimal IM for long-span cable-stayed bridge systems. Results show that incorporating SMA wires in roller bearings can decrease the failure probabilities of the bearing. The piers and towers with SMA-RBs lead to lower seismic fragility over the towers and piers in the reference bridges. The RS is the most vulnerable bridge whereas the SMA-RBS is the least vulnerable bridge among the four bridges. The SMA-RBS experience a much lower collapse damage probability compared to RS ad FS. [ABSTRACT FROM AUTHOR]

The study was conducted to identify relationships between single nucleotide polymorphisms (SNPs) in the NOD1 and NLRP9 genes and resistance to H. contortus infestation in goats in China and Bangladesh. A total of 507 unrelated goats from 6 different populations were sampled. Fecal egg count (FEC) was determined and genomic DNA was extracted from those goats. Touchdown PCR assays were used to genotype each of the target SNP. An association study was carried out using a generalized linear model and R software after transforming the FEC as log10 (FEC + 25). All breeds of goat in Bangladesh had lower mean FEC than any of the Chinese breeds. Two single nucleotide polymorphisms (SNPs) viz. NOD1_146_A>G (p<0.001) and NLRP9_43_A>G (p<0.003) were significantly associated with FEC trait after H. contortus infection. Goats with the GG genotype for NOD1_146_A>G (904.43 ± 140.65epg) and the AA genotype for NLRP9_43_A>G (1129.57 ± 196.5 epg) had higher FEC than goats with the AA genotype (396.68 ± 67.22 epg) or the GG genotype (399.12 ± 106.4 epg) at the respective loci. NOD1 and NLRP9 genes were significantly associated with FEC and might be related to resistance to H. contortus infection in goats. [ABSTRACT FROM AUTHOR]

China which is emerging as a significant regional power with the phenomenal growth in its economic and other security sectors, is trying to take the potential advantage of its locational benefit. Opening up its economy, improving bilateral and multilateral relations, resolving disputes amicably, assisting others by way of investments etc. and trying to keep up with peaceful co-existence principle, are some of its image building initiatives. Apart from this, China has been focusing on to invest in and access to Central Asian resources, particularly, hydrocarbon in view of its growing energy demand. In addition to re-drawing its regional policy and strategy owing to some recent developments on its western borders, Beijing is trying its best to strike a balance between the fast changing developments and its strategic interests in Central Asia which is seen as one of the best alternative for its energy accomplishments. This article focuses on China's strategic engagements with Central Asian states, particularly, in the aftermath of the disintegration of the Soviet Union. After analysing various compulsions and threat perceptions caused by the un-accounted nuclear fissile materials and nuclear weapons in Central Asia, particularly, in Kazakhstan, the paper talks about bilateral military and security cooperation, confidence-building measures within the framework of SCO, bilateral economic engagements and energy cooperation. [ABSTRACT FROM AUTHOR]

A total of 53 methicillin-resistant coagulase-negative staphylococci strains isolated in a hospital in Guangzhou, China, were analyzed to detect class 1 integrons and SCC mec typing. Thirty strains had the class 1 integrase ( intI1) gene and 26 strains possessed the 3′ conserved region of qacEΔ 1- sul1. Four different types of gene cassette arrays were found and a highly prevalent array of dfrA12-orfF-aadA2 gene cassettes was observed. Thirty class 1 integron-positive coagulase-negative staphylococci strains were subjected to Southern hybridization analysis; the result showed that class 1 integrons were located on chromosome, not plasmid. According to the results of SCC mec typing for 30 integron-bearing MRCNS strains, five, 15 and five strains belonged to type I, II and III SCC mec, respectively, and five strains were untypeable. For 23 non-integron-bearing methicillin-resistant coagulase-negative staphylococci strains, four, nine and seven strains belonged to type I, II and III SCC mec, respectively, and three strains were untypeable. None of the strains belonged to type IV or V. Twenty-three coagulase-negative staphylococci isolates of three Staphylococcal species that contained the dfrA12-orfF-aadA2 gene cassette array were phylogenetically unrelated to each other by randomly amplified polymorphic DNA, indicating that the gene cassettes might be disseminated in the clinical strains by a horizontal gene transfer. [ABSTRACT FROM AUTHOR]

Yaks are a major source of livelihood for the high landers where agriculture does not exist. This multipurpose animal has remained a subject of studies since the second half of 18th century. However, there is limited data available on the chemistry of yak milk in China. The objective of this study was to analyze the chemical composition and nutrient profiles of Chinese yak milk. Fresh milk samples from 7 mid-lactating yaks (Maiwa breed) in Hongyuan county of Sichuan Province in China were collected, pooled, lyophilized and stored at -20 °C before use. Gross composition (total solids, protein, fat, ash, and lactose), minerals, and profiles of fatty acids, amino acids and proteins of the milk samples were examined. The average values of gross composition were 14.35% total solids, 3.51% protein, 5.80% fat, 3.90% lactose, and 0.58% ash in the yak milk. The levels of Ca, Na, K, Mg, Zn, and Fe were 1149.4, 276.8, 1066.1, 105.3, 6.9, and 1.5 mg/L, respectively. Gas liquid chromatography analysis of milk fat showed that major fatty acids in yak milk were C16:0, C18:1, C18:0, and C14:0. There was a small amount (2.68 mg/g fat) of conjugated linoleic acid in yak milk. Results of amino acid analysis indicated that glutamic acid (183.79 mg/g protein) was the most abundant amino acid in yak milk. The mean values of lysine and methionine were 81.01 and 30.61 mg/g protein, respectively. The total essential amino acid percentage is 46.36% which suggests that the yak milk may be a good supply of essential amino acids. SDS-PAGE and densitometry results demonstrated that, similar to cow's milk, the major proteins in yak milk are caseins, which accounts for over 60% relative percentage of total proteins. The relative percentage of α-lactalbumin in yak milk was significantly lower (P < 0.05) compared to bovine milk. As information about yak milk chemistry is limited, especially in China, more systematic studies in this area are needed in order to utilize this valuable resource. [ABSTRACT FROM AUTHOR]

Oligosaccharides are the third most abundant solid constituents in human milk in which these are believed to play two major roles i.e., defense agents by acting as receptor analogues to inhibit the binding of enteropathogens to the host cell receptors and bifidogenic factors. Cow's milk is in lack of oligosaccharides and infant formulas made with cow's milk may be deficient in oligosaccharides. It is believed that supplementing infant formula with certain oligosaccharides could improve the nutritional value of formula and help mimic some of physiological functions of mother's milk. The objective of the present study was to quantify fructooligosaccharides in infant formula. Infant formulas, seven from China and three from the United States of America, were collected and analyzed for fructooligosaccharide content using a colorimetric method. The principle of the method is that sucrose, starch and maltosacchrides (if present in the sample) are hydrolyzed to D-glucose by sucrase, amylase and maltase, respectively. Fructooligosaccharides are hydrolyzed to fructose and glucose by fructanase enzyme and the reducing sugars are reacted with p-hydroxybenzoic acid hydrazide resulting in color which is measured at 410 nm using a spectrophotometer. Fructooligosaccharide content of most infant formulas analyzed ranged from 0.10±0.01% to 0.52±0.14% and only one formula had 1.39±0.20%. [ABSTRACT FROM AUTHOR]

Abstract: A total of 387 retail meat, seafood and milk powder samples were collected from nine cities in northern China in 2005 and screened for the presence of Salmonella. Salmonella strains isolated were subjected to serotyping and antimicrobial susceptibility testing. Salmonella was isolated from 81 (20.9%, 81/387) samples and classified into 23 serotypes. The isolates were frequently resistant to sulfamethoxazole (86.4%), sulfamethoxazole/trimethoprim (48.1%), nalidixic acid (30.9%), tetracycline (19.8%), carboxybenzylpenicillin (17.3%), amoxicillin (17.3%) and ampicillin (16.0%). The multiple resistance (resistance to ≥3 antibiotics) was found in 29.6% (n=24) isolates. Additionally, 4 isolates from chicken displayed the ACSSuTNx profile, resistant to ampicillin, chloramphenicol, streptomycin, sulfonamide, tetracycline and nalidixic acid, in particular, strain HBS084 showing the resistance to as many as 20 antibiotics. Salmonella from chicken showed the higher frequency of antimicrobial resistance. Our findings indicate that in northern China food products of animal origin can be a source of exposure for consumers to multiresistant Salmonella strains. [ABSTRACT FROM AUTHOR]

• The friction spring-based self-centering rocking core (SRC) is introduced to improve the resilience of the beam-through frames (BTFs). • Quasi-static tests and hybrid tests were conducted to investigate the seismic performance of the SC device and the SRC, respectively. • A parametric numerical study was performed to investigate the two stiffness parameters of the SC device on the seismic performance of the system. Beam-through frames (BTFs) are gradually becoming popular as low-to-medium rise buildings in China because of their economic benefits and fast construction. However, BTFs are prone to soft-story failure mechanisms, especially under the ultimate stage. The self-centering rocking core (SRC), composed of a steel truss rocking core and a friction spring-based self-centering (SC) device, is introduced to improve the resilience of the BTF. Quasi-static tests and hybrid tests were conducted to investigate the seismic performance of the SC device and the SRC, respectively. Quasi-static tests demonstrate that the SC device has highly stable flag-shaped hysteretic behavior under two different loading protocols. Hybrid tests reveal that the system could realize the target seismic performance with an effectively controlled deformation pattern under both far-field (FF) and near-fault (NF) pulse-like ground motions. Based on the experimental results, the uniaxial material model of the SC device and the numerical model of the system were verified. Subsequently, a parametric study was performed to investigate the influence of two stiffness parameters (i.e., the ratio of the initial actual (experimental) compression stiffness to the initial theoretical compression stiffness (κ) and the ratio of the initial actual tension stiffness to the initial actual compression stiffness (ρ)) of the SC device on the seismic performance of the system. The incremental dynamic analysis (IDA) results show that the collapse capacity of the system increases first and then decreases with the increase in κ values and a larger ρ leads to a larger collapse capacity of the system. Besides, the influence of such stiffness parameters on the peak responses of the system under various seismic hazard levels was also investigated. The strategy employing the SRC could realize a uniform peak inter-story drift (PID) distribution of BTFs while the peak floor acceleration (PFA) tends to be concentrated on the upper floors. [ABSTRACT FROM AUTHOR]

As a novel antibiotic resistance determinant, investigation of the occurrence and characteristics of class 1 integron was performed on nosocomial methicillin-resistant Staphylococcus aureus (MRSA) strains sampled during 2001-2006. Seventy-six out of 179 (42.5%) of the tested strains were found to carry class 1 integrons, with four unique arrays of gene cassettes detected. This is the first report of the comprehensive identification and typing of class 1 integrons in clinical MRSA isolates over a 6-year period, representing the first evidence for class 1 integrons as possible antibiotic resistance determinants in clinical MRSA strains. [ABSTRACT FROM AUTHOR]

• Smooth cable force distribution in a cable-stayed bridge can be represented by a cubic B-Spline interpolation curve. • A number of reasonable local minima of the objective function can be generated for the proposed method. • The optimum solution can be selected as the minimum of the generated local minima. • The proposed method of determining the optimum cable forces can be easily implemented in practice. Cable-stayed bridges have been extensively constructed in China in the recent two decades. This type of bridge is characterized by flexible cables that transfer the deck loads to pylons. This study focuses on the cable force optimization of a curved cable-stayed bridge based on the proposed method where simulated annealing and cubic B-Spline interpolation curves are combined for the optimization. Firstly, the numerical model of a curved cable-stayed bridge is generated in OpenSees platform. Secondly, the proposed method is elaborately described, including the establishment of cubic B-Spline interpolation curves based on four interpolation points, the flow chart of simulated annealing algorithm, objective function, design variables, and design load cases. Finally, the static responses of the bridge deck, pylons, and cables are calculated and discussed under the obtained optimum cable forces. The results reveal that the currently proposed method can efficiently generate a number of values for the objective function, and the optimum solution can be selected as the minimum of the generated objective function values. In addition, cable forces obtained by the proposed method change gradually. The proposed method for determining the optimum cable forces can be easily implemented in practice. [ABSTRACT FROM AUTHOR]

This study utilized surface sediments from a potentially less polluted transboundary Himalayan River (Brahmaputra: China-India-Bangladesh) to investigate the abundance of 15 geochemically and ecologically significant elements and to predict their sources and ecological consequences. INAA was applied to determine the elemental concentrations. The average abundances (μg.g -1 ) of Rb (94.20), Cs (4.49), Th (20.31), & U (2.73) were 1.12-2.26 folds elevated than shale. Environmental indices disclosed a pollution status ranging from "uncontaminated to moderately contaminated," with minimal Rb, U, and Th enrichment in the downstream zone. Consensus-based sediment quality guideline (SQG) threshold values suggested that only Cr (60% samples > TEL) may impose rare biological effects. Ecological risk indices suggested "minor to no" possible eco-toxicological risks for the accounted elements (Cr, Co, Mn, Zn, Sb, & As). The positive matrix factorization (PMF) model predicated the predominance of geogenic or crustal contributions (∼72.69%) for Al, K, Na, Ti, Co, Zn, Ba, Cs, As, Rb, Th, & U derived from elemental fractionations, mineral weathering, and bio-geo-chemical mobilization. The relative contributions of anthropogenic sources (∼27.31%; such as the construction of roads, settlement expansion, litter disposal, municipal waste discharge, mining activities, agricultural encroachment, etc.) on elemental distribution were significantly lower. The abundance of Cr and Mn was mainly influenced by anthropogenic sources. This study demonstrated the effectiveness of utilizing geo-environmental guidelines and receptor models in discriminating the natural & anthropogenic origins of metals in the complex riverine sediments of a less anthropogenically affected river., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

The consequences of climate change, food security, and self-sufficiency goals are driving excessive human activity onto vegetable farms in Bangladesh, and harmful heavy metal exposure is spreading. So, the study assessed the toxic metals (Pb, Cd, and Cr) exposure, characteristics, and human health risk regarding the soil-vegetable system of two distinct locations in Bangladesh using atomic absorption spectrometry. The average concentration of metals in soil and fertilizer/pesticide samples followed the same order (Cr > Pb > Cd), but for vegetable samples, the order was Pb > Cr > Cd, with some extra Pb compared to the World Health Organization (WHO) allowable limit (0.3 mg/kg). Low levels of pollution with negligible ecological concerns were predicted for both locations by the soil quality indexing. But industrial influence boosted the Pb content in location B, and common sources (fertilizer/pesticide) for both locations might be responsible for a moderate level of Cd. The toxic metals transferred to vegetables followed the trend of Cd > Pb > Cr. However, the human health risks arising from harmful metals exposure at both locations were ineffective (< 1) in evaluating noncarcinogenic risk patterns through the target hazard quotient (THQ), total THQ, and hazard index (HI). Again, considering probable carcinogenic risk patterns, vegetable consumption with studied exposure levels of toxic metals followed within the acceptable range (between 1.0E-04 and 1.0E-06). Overall, location B is slightly more vulnerable than location A by considering metal exposure, pollution distribution, and risk evaluation in the study area (significant at p < 0.05). So, systematic monitoring and protective measures are required to ensure food safety and sustainable vegetable production., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: Recent gains in reducing the global burden of malaria are threatened by the emergence of Plasmodium falciparum resistance to artemisinins. The discovery that mutations in portions of a P. falciparum gene encoding kelch (K13)-propeller domains are the major determinant of resistance has provided opportunities for monitoring such resistance on a global scale., Methods: We analyzed the K13-propeller sequence polymorphism in 14,037 samples collected in 59 countries in which malaria is endemic. Most of the samples (84.5%) were obtained from patients who were treated at sentinel sites used for nationwide surveillance of antimalarial resistance. We evaluated the emergence and dissemination of mutations by haplotyping neighboring loci., Results: We identified 108 nonsynonymous K13 mutations, which showed marked geographic disparity in their frequency and distribution. In Asia, 36.5% of the K13 mutations were distributed within two areas--one in Cambodia, Vietnam, and Laos and the other in western Thailand, Myanmar, and China--with no overlap. In Africa, we observed a broad array of rare nonsynonymous mutations that were not associated with delayed parasite clearance. The gene-edited Dd2 transgenic line with the A578S mutation, which expresses the most frequently observed African allele, was found to be susceptible to artemisinin in vitro on a ring-stage survival assay., Conclusions: No evidence of artemisinin resistance was found outside Southeast Asia and China, where resistance-associated K13 mutations were confined. The common African A578S allele was not associated with clinical or in vitro resistance to artemisinin, and many African mutations appear to be neutral. (Funded by Institut Pasteur Paris and others.).

As a novel antibiotic resistance determinant, investigation of the occurrence and characteristics of class 1 integron was performed on nosocomial methicillin-resistant Staphylococcus aureus (MRSA) strains sampled during 2001-2006. Seventy-six out of 179 (42.5%) of the tested strains were found to carry class 1 integrons, with four unique arrays of gene cassettes detected. This is the first report of the comprehensive identification and typing of class 1 integrons in clinical MRSA isolates over a 6-year period, representing the first evidence for class 1 integrons as possible antibiotic resistance determinants in clinical MRSA strains., (© 2010 The Authors. Clinical Microbiology and Infection © 2010 European Society of Clinical Microbiology and Infectious Diseases.)

Class 1 and 2 integrons were detected in 45.8% (54/118) and 19.5% (23/118) of our tested Pseudomonas aeruginosa isolates, respectively. Three strains were positive for both the integrons. This is the first report of class 2 integrons in P. aeruginosa and also of isolates carrying class 1 and 2 integrons simultaneously.

The aim of the present study was to determine the source of nosocomial outbreak due to Burkholderia cepacia by molecular techniques. A total of 11 B. cepacia strains were isolated; nine from blood and one from sputum of patients without cystic fibrosis, and one from reverse osmosis water at a local hospital in Guangzhou, China. Analyses of 11 strains by the Sau-PCR assay and pulsed-field gel electrophoresis revealed that nine strains obtained from the blood of outpatients in a hemodialysis unit and one strain from reverse osmosis water had identical DNA profiles, indicating that the reverse osmosis water supply could be a source of infection.

The marine dinoflagellate genus Alexandrium includes a number of species that produce potent neurotoxins responsible for paralytic shellfish poisoning, which in humans may cause muscular paralysis, neurological symptoms and, in extreme cases, death. Because of the genetic diversity of different genera and species, molecular tools may help to detect the presence of target microorganisms in marine field samples. Here we employed a loop-mediated isothermal amplification (LAMP) method for the rapid and simple detection of toxic Alexandrium species. A set of four primers were designed based upon the conserved region of the 5.8S rRNA gene of members of the genus Alexandrium. Using this detection system, toxic Alexandrium genes were amplified and visualized as a ladder-like pattern of bands on agarose gels under isothermal condition within 60 min. The LAMP amplicons were also directly visualized by eye in the reaction tube by the addition of SYBR Green I. This LAMP assay was 10-fold more sensitive than a conventional PCR method with a detection limit of 5 cells per tube when targeting DNA from Alexandrium minutum. The LAMP assay reported here indicates the potential usefulness of the technique as a valuable simple, rapid alternative procedure for the detection of target toxic Alexandrium species during coastal water monitoring.