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Cooling systems provide a safe thermal environment for the reliable operation of IT equipment in data centers (DCs) while generating significant energy consumption. Therefore, to achieve energy savings in cooling system control under dynamic thermal distribution in DCs, this paper proposes a multi-setpoint cooling control approach based on deep reinforcement learning (DRL). Firstly, a thermal model based on the XGBoost algorithm is constructed to precisely evaluate the thermal distribution in the rack room to guide real-time cooling control. Secondly, a multi-set point cooling control approach based on the deep Q-network algorithm (DQN-MSP) is designed to finely regulate the supply air temperature of each air conditioner by capturing the thermal fluctuations to ensure the dynamic balance of cooling supply and demand. Finally, we adopt the extended CloudSimPy simulation tool and the real workload trace of the PlanetLab system to evaluate the effectiveness and performance of the proposed approach. The simulation results show that the proposed control solution effectively reduces the cooling energy consumption by over 2.4% by raising the average air supply temperature of the air conditioner while satisfying the thermal constraints. [ABSTRACT FROM AUTHOR]

Phenol is a toxic organic molecule that is widely detected in the natural environment, even in drinking water sources. Biological methods were considered to be a good tool for phenol removal, especially microbial immobilized technology. However, research on the "seed" bacteria along with microbial community analysis in oligotrophic environment such as drinking water system has not been addressed. In this study, Acinetobacter sp. DW-1 with high phenol degradation ability had been isolated from a drinking water biofilter was used as seeded bacteria to treat phenol micro-polluted drinking water source. Meanwhile, the whole genome of strain DW-1 was sequenced using nanopore technology. The genomic analysis suggests that Acinetobacter sp. DW-1 could utilize phenol via the β-ketoadipate pathway, including the catechol and protocatechuate branches. Subsequently, a bio-enhanced polyhedral hollow polypropylene sphere (BEPHPS) filter was constructed to investigate the stability of the seeded bacteria during the water treatment process. The denatured gradient gel electrophoresis (DGGE) profile and the quantification of phenol hydroxylase gene results indicate that when the BEPHPS filter was operated for 56 days, Acinetobacter sp. was still a persistent and competitive bacterium in the treatment group. In addition, 16S rRNA gene amplicon sequencing results indicate that Acinetobacter sp., as well as Pseudomonas sp. , Nitrospira sp., Rubrivivax sp. were the predominant bacteria in the treatment group, which were different from that in the CK group. This study provides a better understanding of the mechanisms of phenol degradation by Acinetobacter sp. DW-1 at the gene level, and provides new insights into the stability of seeded bacteria and its effects on microbial ecology during drinking water treatment. [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa is an important opportunistic pathogen and remains a major threat to the microbial safety of drinking water. There is a lack of comprehensive data on P. aeruginosa contamination in drinking water in China. Therefore, this study aimed to determine the prevalence, genetic diversity, virulence genes, and antimicrobial resistance of P. aeruginosa isolated from mineral water and spring water in China. From January 2013 to January 2014, 314 drinking water samples were collected from 23 cities in China. Of the collected samples, 77 (24.5%) were contaminated with P. aeruginosa , and these comprised 34 raw water (30.4%), 39 activated carbon-filtered water (30.6%), and four final water product (3.9%). A total of 132 P. aeruginosa isolates were obtained, and all of them showed the presence of virulence genes, with the detection rates of ExoU , ExoS , phzM , toxA , and lasB genes being 7.6, 86.3, 95.5, 89.4, and 100%, respectively. All isolates were sensitive to the 14 antibiotics (ciprofloxacin, levofloxacin, ofloxacin, norfloxacin, gentamicin, tobramycin, amikacin, polymyxin B, imipenem, meropenem, aztreonam, ceftazidime, cefepime, and piperacillin/tazobactam) tested. The 132 isolates were categorized into 42 sequence types according to multilocus sequence typing, and ST235 accounted for 8.3% (11) of the total isolates. Thus, this study provides comprehensive data on the prevalence and characteristics of P. aeruginosa in drinking water in China and can aid in developing preventive measures against contamination during the drinking water treatment process. [ABSTRACT FROM AUTHOR]

The aim of this study was to gain insight into the bacterial composition and dynamics in a mineral water treatment system (MWTS). The bacterial community of a full-scale mineral water treatment plant in the Maofeng Mountain, South China, was studied using high-throughput sequencing combined with cultivation-based techniques in both the dry and wet season. Overall, adenosine tri-phosphate (ATP) concentration (6.47 × 10-11 – 3.32 × 10-8 M) and heterotrophic plate counts (HPC) (3 – 1.29 × 103 CFU/mL) of water samples in the wet season were lower than those (ATP concentration 5.10 × 10-11 – 6.96 × 10-8 M, HPC 2 – 1.97 × 103 CFU/mL) in the dry season throughout the whole MWTS. The microbial activity and biomass of water samples obviously changed along with treatment process. All 300 isolates obtained using cultivation-based techniques were distributed in 5 phyla, 7 classes, and 19 genera. Proteobacteria accounted for 55.7% (167) of the total isolates, among which predominant genus was Pseudomonas (19.3%). Illumina sequencing analysis of 16s rRNA genes revealed 15 bacterial phyla (relative abundance >0.1%) as being identified in all water samples. Among these, Proteobacteria constituted the dominant bacteria microbiota in all water samples. A large shift in the proportion of Bacteroidetes, Actinobacteria , and Firmicutes was obtained during the treatment process, with the proportion of Bacteroidetes, Actinobacteria decreasing sharply, whereas that of Firmicutes increased and predominated in the final water product. The core microbiome, which was still present in whole MWTS comprised several genera including Pseudomonas , Acinetobacter , Clostridium , and Mycobacterium , that contain species that are opportunistic pathogens, suggesting a potential threat for mineral water microbiology safety. This study is the first to investigate the bacterial community of a full-scale mineral water treatment plant in China. The results provided data regarding the bacteria composition and dynamics in an MWTS, which will contribute to the beneficial manipulation of the mineral water microbiome. [ABSTRACT FROM AUTHOR]

Recently researchers have proposed innovative solutions aiming to improve the energy performance of building envelope components such as Trombe walls, ventilated storage walls. The principle of all the innovative systems can be simplified as heat/cold sources in walls. However, the thermal performance and energy savings potential of the innovative heating walls comparing to the traditional heating pattern with heat sources in room air are still lack of clarification. In this paper, the thermal response of an ideal building model under two ideal heating patterns, are analyzed by using a simple thermal and airflow macroscopic model. The analytical formulas for indoor air temperature and thermal mass temperature are also derived to identify the critical parameters that affect the levels and fluctuations of them. By numerical calculation, it can be observed that the indoor air temperature under HP1 quickly falls down as the heat source removed and has big variation, while the results of HP2 look favourable with less variation, and the mean air temperature during the non-heating period is higher than that of HP1. This implies that the heating pattern HP2 has the potentials to create a stable indoor thermal environment. [ABSTRACT FROM AUTHOR]

We developed a new efficient method for the synthesis of important indoxyl glycoside substrates for β-glucosidase and β-galactosidase by using 1-acetylindol-3-ones as intermediates. This method was used to synthesise novel precipitating fluorogenic substrates for β-glucosidase based on 2-(benzothiazol-2′-yl)-phenols. We also assessed the application of these substrates in the detection of foodborne pathogenic bacteria. [ABSTRACT FROM AUTHOR]

Salmonella enterica subsp. enterica serovar ,4,[5],12:i:- is a monophasic variant of Salmonella Typhimurium, which has recently been recognized as an emerging cause of infection worldwide. This bacterium has also ranked among the four most frequent serovars causing human salmonellosis in China. However, there are no reports on its contamination in Chinese food. Serotyping, polymerase chain reaction, antibiotic resistance, virulotyping, and multilocus sequence typing (MLST) assays were used to investigate the prevalence of this serological variant in food products in China, and to determine phenotypic and genotypic difference of monophasic isolates and Salmonella Typhimurium isolated over the same period. Salmonella ,4,[5],12:i:- was prevalent in various food sources, including beef, pork, chicken, and pigeon. The study also confirmed the high prevalence (53.8%) of resistance to ampicillin, streptomycin, sulfonamides, and tetracycline in Salmonella ,4,[5],12:i:-, which was higher than that in Salmonella Typhimurium. Moreover, Salmonella ,4,[5],12:i:- isolates in our study were different from Salmonella Typhimurium isolates by the absence of three plasmid-borne genes (spvC, pefA, and rck) and the presence of gipA in all isolates. All Salmonella ,4,[5],12:i:- isolates demonstrated MLST pattern ST34. Genomic deletions within the fljBA operon and surrounding genes were only found in Salmonella ,4,[5],12:i:- isolates, with all isolates containing a deletion of fljB. However, hin and iroB were identified in all Salmonella ,4,[5],12:i:- isolates. Three different deletion profiles were observed and two of them were different from the reported Salmonella ,4,[5],12:i:- clones from Spain, America, and Italy, which provided some new evidence on the independent evolution of the multiple successful monophasic clones from Salmonella Typhimurium ancestors. This study is the first report of Salmonella ,4,[5],12:i:- in food products from China. The data are more comprehensive and representative, providing valuable information for epidemiological studies, risk management, and public health strategies. [ABSTRACT FROM AUTHOR]

we report an unusual case of a patient who presented with neuroleptic malignant syndrome (NMS) associated with hiccough therapy, together with a review of the current knowledge on NMS. A 70-year-old male patient rapidly developed significant hyperthermia, rigidity, and unconsciousness and upregulated serum creatine kinase after 3 days of receiving a parenteral high dose of haloperidol. The diagnosis of NMS was established, discontinued haloperidol and dantrolene administration via nasogastric tube made him rehabilitation. which makes the clinicians be vigilant of the utilization of haloperidol and other antipsychotics, especially for non-psychosis use. [ABSTRACT FROM AUTHOR]

Traditional medicinal herbs are widely used and may be contaminated with mycotoxigenic fungi during cultivation, harvesting, and storage, causing spoilage and mycotoxin production. We evaluated the predominant mycoflora and extent of mycotoxin contaminations in 48 contaminated samples of 13 different medicinal herbs. In total, 70.8% of herbs were slightly contaminated with aflatoxins (<5 μg kg−1). Codonopsis radix samples contained ochratoxin A (OTA) (360–515 μg kg−1), and Scutellariae radix samples contained OTA (49–231 μg kg−1) and citrinin (15–53 μg kg−1). Forty samples (83.3%) contained fungal contamination. Sixty-nine strains were characterized via morphological and molecular identification. The predominant mycoflora comprised four genera, Aspergillus spp. (26.1%), Penicillium spp. (24.6%), Rhizopus spp. (14.5%), and Trichoderma spp. (11.6%). Aflatoxins, OTA, and citrinin were detected in 37 cultures by high-performance liquid chromatography-tandem mass spectrometry. Approximately 21.6% of Aspergillus and Penicillium isolates produced mycotoxins. One Penicillium polonicum strain isolated from Scutellariae radix synthesized citrinin. Multiplex PCR analysis showed that three Aspergillus flavus strains harbored aflatoxin biosynthesis genes. One Aspergillus flavus strain isolated from Amomi fructus produced AFB1 and AFB2. To the best of our knowledge, the citrinin production by Aspergillus chevalieri and Penicillium sacculum was first reported in this study, which poses a potential risk of mycotoxin contamination in medicinal herbs. [ABSTRACT FROM AUTHOR]

Infections due to aquatic products that are contaminated with Salmonella spp. are great risks to public health, however, epidemiological information and risk factors regarding these Salmonella contamianted food are limited in China. The study aimed to examine the incidence of Salmonella spp. in fresh aquatic products in China, and the MLST patterns and antimicrobial-resistance profiles of the Salmonella isolates identified. Out of the 300 aquatic food samples purchased from retail markets in 15 provincial Chinese capitals during 2015.6–2016.6, sixteen (5.3%) were found to be positive for Salmonella spp. and fifteen distinct serovars were detected. Clinically-important serovars predominated the isolates recovered, with almost all other identified serovars also implicated in human diseases. Antimicrobial susceptibility analysis of the 18 non-repetitive isolates showed that 14 isolates (77.8%) present drug resistance and seven isolates (38.9%) showed multidrug resistance phenotypes. High frequencies of resistance to streptomycin (66.7%), ampicillin (38.9%), and tetracycline (33.3%) were observed. Of particular concern, 22.2% of isolates were resistant to ciprofloxacin. The incidence of Salmonella serovars in the retail aquatic products and their high antimicrobial-resistance frequencies could constitute potential risks to public health. This study is valuable for supporting risk assessment, epidemiological investigation, and disease prevention. • Aquatic products in this study were found highly contaminated with Salmonella spp.. • Clinically-important serovars predominated the isolates recovered in this study. • All of the identified serovars have previously been implicated in human diseases. • The Salmonella isolates recovered showed high antimicrobial-resistance frequencies. • These antimicrobial-resistant Salmonella spp. are potential risks to human health. [ABSTRACT FROM AUTHOR]

Noroviruses are still the primary cause of non-bacterial acute gastroenteritis worldwide. Recently, a novel GII.17 norovirus variant emerged and caused an infection peak in the cold season of 2014/2015 in some Asian countries, including China. In this study, in order to understand the evolutionary advantage of the novel variant, complete genomic sequences of GII.17 NoV strains from South China were comprehensively analyzed. Pairwise alignments of new GII.17 genomes with representative sequences of each GII genotype were performed. Inconsistent homology was observed between different protein-encoding regions, of which VPg (NS5) and P2 were found to be the most conserved and variable ones, respectively. The differences between new sequences and other reported GII.17 genomes were also compared, and 84 mismatched nucleotides were found, resulting in 15 amino acid changes. Then, all capsid sequences of different GII.17 NoV variants were collected for multiple alignments, and a total of 87 spots were identified during their evolution process. Homology modeling of capsid proteins of four GII.17 variants was carried out based on comparison with GII.4 VA387 strain, and structural differences were mainly embodied in five extended loops. Furthermore, positions of potential conformational epitope regions of new GII.17 variants were found more similar or adjacent to those of GII.4 rather than those of the former GII.17 variants. In summary, nine GII.17 strains from South China were extensively characterized based on their complete genomes, and a different distribution pattern of epitope residues was predicted on the new GII.17 variant capsid from that of the former ones. [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa is an important opportunistic pathogen in drinking water and monitoring P. aeruginosa strains is of importance for microbial safety. Here, prevalence of P. aeruginosa in drinking water samples (n = 206) from Guangdong of China were surveyed, and then P. aeruginosa were further characterized by DNA-based fingerprinting and detection of virulent factors. Result indicated that 25% of source water, 32.3% of carboned water, and 4.6% of finished water were positive for P. aeruginosa . Among 43 of P. aeruginosa isolates, ExoU , EcfX , ExoS , phzM , toxA , and lasB genes were present in 20.9%, 100%, 70%, 97.7%, 93% and 100% of isolates respectively. In addition, based on 90% similarity, P. aeruginosa were grouped into thirty-one ERIC types with discriminatory ability ( D ) of 97.34% and thirty-seven RAPD types using primer 208 or 272 independently with D of 99.22%. Some stains including PA4 and PA5 from 5# location; PA38, PA39 and PA40 from 42#; PA18 and PA19 from 7# showed the same types using both ERIC and RAPD typing methods. This study contributes to the valuable information about prevalence of P. aeruginosa in drinking water of Guangdong, and their characterization is helpful to trace the possible origins of P. aeruginosa through the drinking water chain. [ABSTRACT FROM AUTHOR]

Salmonella is a leading cause of foodborne disease worldwide and ready-to-eat (RTE) foods are regarded as a major source of infection and outbreak. In recent years, the consumption of Chinese RTE foods has raised markedly with the pace of life increasing. However, the prevalence of Salmonella in these foods in China and its potential risk to public health has not been well determined and evaluated. This study was undertaken to investigate the prevalence of Salmonella in Chinese retail RTE food products and to determine serotype distribution, antimicrobial resistance, virulence, and genetic diversity of recovered Salmonella isolates. Out of the 539 RTE food products collected and tested from July 2011 to May 2014, 19 (3.5%) were positive for Salmonella . The contamination levels of Salmonella were mostly in the range of 0.3–10 most probable number (MPN)/g, with one sample exceeding 110 MPN/g. Among the 50 isolates identified, 37 isolates (74.0%) were resistant to at least one antimicrobial, while 21 isolates (42.0%) were resistant to more than three antimicrobials. High rates of resistance were observed for tetracycline (56.0%), ampicillin (38.0%), and streptomycin (34.0%). PCR analysis of 15 virulence genes showed that the avrA , ssaQ , mgtC , siiD , sopB , and bcfC genes were detected in all 50 isolates, whereas the genes located on plasmid and prophage varied significantly among the isolates. Ten distinct serovars were identified and S . Derby, S. Meleagridis, S . Enteritidis, and S. Senftenberg were the most prevalent serovars. A total of 11 sequence types by multilocus sequence typing and 20 profiles by pulsed-field gel electrophoresis were generated for the 20 selected isolates and the combination of these two methods presented a better knowledge of genetic diversity of Salmonella isolates. The study provided a systematical surveillance on prevalence of Salmonella in Chinese RTE foods and indicates its potential risk to public health. [ABSTRACT FROM AUTHOR]

Noroviruses (NoVs) are the primary cause of non-bacterial acute gastroenteritis worldwide. Most NoV infections are caused by GII.4, but GII.6 is also an important genotype with a long-term persistence in human populations. In this study, the complete genome sequence of a NoV strain GZ2010-L96 isolated in China was identified and analyzed phylogenetically. The viral genome comprised 7550 nucleotides, and its phylogenetic analysis revealed that the strain belonged to GII.6 genotype. All reported GII.6 NoV capsid protein sequences were also collected for comparative analysis, and GZ2010-L96 was clustered into GII.6-b with other 8 strains. Meanwhile, it was found that 53 spots on viral capsid showed subcluster specificity according to multiple alignments. Moreover, homologous modeling of GZ2010-L96 based on comparison with GII.4 VA387 strain showed a different antigen distribution pattern. In summary, the genome of the GII.6 strain GZ2010-L96 detected in China was extensively characterized, and phylogenetic analyses of GII.6 NoVs based on the capsid proteins may reveal a different evolution process from the predominant genotype GII.4. [ABSTRACT FROM AUTHOR]

Human T-lymphotropic virus (HTLV) infection is a high risk factor for lymphoproliferative, inflammatory, and infectious disorders. The epidemiology of HTLV-I, II in industrialized countries has been intensively investigated, and mandatory screening of blood supplies for HTLV-I/II was implemented in mid-1980s in most developed and several developing countries, yet no expanding investigation has been executed in China so far and also been considered as a non-endemic region. However, Gessain et al. reported that the current number of HTLV carriers in the highly populated China is very probably much higher. Therefore, gaining insight into the epidemiology of HTLV infections is essential for avoiding HTLV-induced risk. To introduce the history and renew the HTLV infection in China, we reviewed literatures and conducted an investigation among blood donors in 9 provinces in China. Concluded from the historical and renewed data, the HTLV screen in China can be divided into three stages. [ABSTRACT FROM AUTHOR]