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Artificial optical synaptic devices with ultra-low power consumption

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Light(Science & Applications) 2023年第1期12卷 25-27页

作者： Guoqiang Li State Key Laboratory of Luminous Materials and Devices South China University of TechnologyGuangzhou 510641China

A BP/CdS heterostructure-based artificial photonic synapse with an ultra-low power consumption is proposed,presenting great potential in high-performance neuromorphic vision systems.

关键词： power optical low

low nutrient levels as drinking water conditions can reduce the fitness cost of efflux pump-mediated ciprofloxacin resistance in Pseudomonas aeruginosa

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Journal of Environmental Sciences 2019年第9期31卷 123-132页

作者： Wenfang Lin Kun Wan Jie Zeng Jingjing Li Xi Li Xin Yu Key Lab of Urban Environment and Health Institute of Urban Environment Chinese Academy of Sciences Xiamen 361021 China University of Chinese Academy of Sciences Beijing 100049 China

The long-term persistence of antibiotic resistance in the environment, especially in drinking water, is a public health concern. Expression of an efflux pump, an important mechanism of resistance to antibiotics, usually confers a fitness cost in bacteria. In this study, we aimed to determine why antibiotic resistance conferred by overexpression of an efflux pump persisted in low-nutrient environments(TOC low or even absent.Competition experiments between wild-type Pseudomonas aeruginosa and ciprofloxacinresistant mutants revealed that the fitness cost of ciprofloxacin resistance significantly decreased(p low-nutrient(0.5 mg/L total organic carbon(TOC)) relative to high-nutrient(500 mg/L TOC) conditions. Mechanisms underlying this fitness cost were analyzed. The mexD gene expression in resistant bacteria(cip3 strain) was significantly lower(p low-nutrient conditions, with 10 mg/L TOC((8.01 ± 0.82)-fold), than in high-nutrient conditions, with 500 mg/L TOC((48.89 ± 4.16)-fold). Moreover, rpoS gene expression in resistant bacteria((1.36 ± 0.13)-fold) was significantly lower(p low-nutrient conditions(10 mg/L TOC),suggesting a growth advantage. Furthermore, the difference in metabolic activity between the two competing strains was significantly smaller(p low-nutrient conditions(5 and 0.5 mg/L TOC). These results suggest that nutrient levels are a key factor in determining the persistence of antibiotic resistance conferred by efflux pumps in the natural environment with trace amounts or no antibiotics.

关键词： Efflux pumps Antibiotic resistance Fitness cost low nutrient nfxB mutation Ciprofloxacin resistance

Realizing stable operation of anaerobic ammonia oxidation at low temperatures treating low strength synthetic wastewater

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Journal of Environmental Sciences 2019年第1期31卷 193-200页

作者： Bowen Zhang Jian Zhao Jiane Zuo Xuchuan Shi Jiayi Gong Haiteng Ren State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua University Beijing Enterprises Water Group Limited SUEZ NWS Company Limited

The low activity of Anammox bacteria at low temperatures and competition from nitrite oxidation bacteria(NOB) when treating low strength wastewater have been major bottlenecks in implementing Anammox in mainstream wastewater treatment. By intermittent high strength feeding(IHSF) and stepwise temperature reduction, stable operation of a granular Anammox reactor was realized at low temperatures(down to 15°C) for 28 days when treating low strength synthetic wastewater. The nitrogen loading rate reached 1.23–1.34 kgN/m^3/day,and the total nitrogen removal rate reached 0.71–0.98 kgN/m^3/day. The IHSF enriched the Anammox sludge in high strength cycles and compensated for sludge loss in low strength cycles, and the high concentration of ammonium in high strength cycles inhibited NOB. The 16 SrRNA gene sequencing results revealed that Candidatus Kuenenia was predominant in the reactor at low temperatures.

关键词： Biological nitrogen removal low temperature Granular Anammox SBR Microbial community

Diclofenac sodium aqueous systems at low concentrations: Interconnection between physicochemical properties and action on hydrobionts

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Journal of Environmental Sciences 2020年第2期32卷 177-186页

作者： Irina S.Ryzhkina Yuliya V.Kiseleva Lyaisan I.Murtazina Tatyana V.Kuznetsova Erik R.Zainulgabidinov Igor V.Knyazev Andrew M.Petrov Sergey E.Kondakov Alexander I.Konovalov Arbuzov Institute of Organic and Physical Chemistry FRC Kazan Scientific CenterRussian Academy of Sciences8 Arbuzov str.Kazan 420088Russia Institute for Problems of Ecology and Mineral Wealth Use of Tatarstan Academy of Sciences 28 Daurskaya Str.Kazan 420087Russia Lomonosov Moscow State University Chemistry Dept.1/3 Lenin HillsMoscow 119899Russia

Diclofenac sodium(DS) is a widely used nonsteroidal anti-inflammatory drug(NSAIDs).NSAIDs are poorly removed during standard wastewater treatment.The consequences of the presence of NSAIDs in rivers and lakes at 10-11–10-8 mol/L are not yet established;therefore, ecotoxicologists have focused their efforts on studying the effect of lowconcentration NSAIDs on fish and hydrobionts, and also on predicting the potential risks to humans.Literature provides some information about the bioeffects of some NSAID solutions in low concentrations but there is no physicochemical explanation for these phenomena.Studying the physicochemical patterns of DS solutions in the low range of concentrations and establishing an interconnection between the solutions’ physicochemical properties and bioeffects can provide a conceptually new and important source of information regarding the unknown effects of DS.The physicochemical properties and action of DS solutions on Ceriodaphnia affinis cladocerans,Paramecium caudatum infusoria, Chlorella vulgaris unicellular green algae, as well as on the growth of the roots of Triticum vulgare wheat seeds, were studied in the calculated concentration range of 1 × 10-3–1 × 10-18 mol/L.The relationship between these phenomena was established using the certified procedures for monitoring the toxicity of natural water and wastewater.It was shown for the first time that water solutions of DS are dispersed systems in which the dispersed phase undergoes a rearrangement with dilution, accompanied by changes in its size and properties, which affects the nonmonotonic dependences of the system’s physicochemical properties and could cause nonmonotonic changes in action on hydrobionts in the low concentration range.

关键词： Diclofenac sodium low concentration Aqueous solutions Physicochemical properties Hydrobionts Toxicity

Impact of preterm birth and low birth weight on medical conditions, medication use and mortality among neonates: a prospective observational cohort study

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World Journal of Pediatrics 2019年第3期15卷 281-288页

作者： Krishna Undela Bashar Talal Saad Mohammed Parthasarathi Gurumurthy Srinivasa Murthy Doreswamy Department of Pharmacy Practice JSS College of Pharmacy.JSS Academy of Higher Education and ResearchSS NagaraMysuru.Karnataka 570 015.India Department of Pediatrics JSS Medical College and Hospital.JSS Academy of Higher Education and ResearchMahatma Gandhi RoadMysuruKarnataka 570 004India

Background There is a paucity of studies conducted in India on neonatal outcomes of preterm birth and low birth weight.Hence,we aimed to assess the impact of preterm birth and low birth weight on medical conditions,medication use and mortality among neonates.Methods A prospective observational cohort study was conducted at the neonatal intensive care unit (NICU) over a period of 9 months.Neonates of either sex,admitted to NICU and who received at least one medication were enrolled in the study.Perinatal and demographic data,reason(s) for NICU admission,diagnoses,medications prescribed,medication-related problems,discharge status and the direct medical cost were documented and analyzed.Results Four hundred and five neonates Were included in the study:60.5% were boys,32.7% were preterm and 44.2% were born underweight.Neonatal sepsis (n =125,16.7%),unconjugated hyperbilirubinemia (n =83,11.1%) and respiratory distress syndrome (n =62,8.3%) were the most common medical conditions and were significantly more common among preterm and underweight neonates.Nearly half of the medications prescribed were anti-infectives for systemic use (n =1310,47.4%).The mean number of medications received by neonates increased from term to extremely preterm (5.2-15.0) and normal birth weight to extremely low birth weight (5.0-14.9).Mortality rate was significantly higher among extremely preterm (66.7%),and very preterm (15.2%) neonates compared to term (2.9%) neonates.The median direct medical cost for NICU admission was INR 21,430 (USD 331).Conclusion Medical conditions,medications prescribed and mortality rate were significantly higher among preterm and underweight neonates admitted to NICU.

关键词： low birth weight Medical conditions Medications Mortality Preterm birth

low rectal cancer:Sphincter preserving techniques-selection of patients,techniques and outcomes

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World Journal of Gastrointestinal Oncology 2015年第7期7卷 55-70页

作者： Nikoletta Dimitriou Othon Michail Dimitrios Moris John Griniatsos 1st Department of Surgery University of AthensMedical SchoolLaiko Hospital

low rectal cancer is traditionally treated by abdominoperineal resection. In recent years, several new techniques for the treatment of very low rectal cancer patients aiming to preserve the gastrointestinal continuity and to improve both the oncological as well as the functional outcomes, have been emerged. Literature suggest that when the intersphincteric resection is applied in T1-3 tumors located within 30-35 mm from the anal verge, is technically feasible, safe, with equal oncological outcomes compared to conventional surgery and acceptable quality of life. The Anterior Perineal Plan E for Ultra-low Anterior Resection technique, is not disrupting the sphincters, but carries a high complication rate, while the reports on the oncological and functional outcomes are limited. Transanal Endoscopic Micro Surgery(TEM) and Trans Anal Minimally Invasive Surgery(TAMIS) should represent the treatment of choice for T1 rectal tumors, with specific criteria according to the NCCN guidelines and favorable pathologic features. Alternatively to the standard conventional surgery, neoadjuvant chemo-radiotherapy followed by TEM or TAMIS seems promising for tumors of a local stage T1sm2-3 or T2. Transanal Total Mesorectal Excision should be performed only when a board approved protocol is available by colorectal surgeons with extensive experience in minimally invasive and transanal endoscopic surgery.

关键词： low rectal cancer Sphincter preservingsurgery Intersphincteric resection Anterior PerinealPlanE for Ultra-low Anterior Resection of the Rectum Total mesorectal excision TransAnal Minimally InvasiveSurgery Transanal Total Mesorectal Excision Quality oflife Oncological outcome Functional outcome

Efficient organic solar cells achieved at a low energy loss

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Science Bulletin 2019年第16期64卷 1144-1147页

作者： Wenrui Liu Jianyun Zhang Shengjie Xu Xiaozhang Zhu Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Organic SolidsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100190China

Organic photovoltaics(OPVs)have attracted much attention because of the advantages in low-cost and large-area fabrication and the great potentials in achieving flexible and semi-transparent devices(1)However,compared with inorganic and perovskite solar cells[2],OPVs show relatively low photoelectric conversion efficiencies,which is admittedly attributed to intrinsically low dielectric constants of organic materials[3]resulting in large energy losses(Eloss=EgqVoc,where Eg is the optical bandgap of the photoactive layer,Voc is the open-circuit voltage of photovoltaic devices and q is elementary charge).

关键词： Efficient organic solar cells at a low energy loss Organic photovoltaics

low loss Z-type Hexaferrites with Bi2O3 Additives for Ultra-high Frequency Antenna Applications

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Journal of Wuhan University of Technology(Materials Science) 2019年第5期34卷 1037-1042页

作者：郭永强 WANG Shizhang 聂彦 School of Optical and Electronic Information Huazhong University of Science and Technology

The Z-type ferrites of nominal composition Ba3Co2 Fe24O41+x wt% Bi2O3, where x=0.25, 0.5, 1.0, 1.5, 2.0, were prepared by conventional ceramic processes. The influence of Bi2O3 content on the bulk densities, microstructures, magnetic and dielectric properties of Z-type ferrite samples were systematically examined so as to obtain materials with low magnetic and dielectric loss tangent over a frequency ranging from 600 to 800 MHz. The experimental results showed that addition of Bi2O3 lowered the sintering temperature(1 020 ℃) and then reduced the average grain size(2.68×10^8 Ω·cm) dramatically, which consequently decreased the magnetic and dielectric loss. Additionally, the low loss factors were observed at the Bi2O3 content x = 1.0, i e, tan δμ/μ’=0.013 and tan δε/ε’= 0.001 at 800 MHz, and such materials could be used for antennas miniaturization from 600 to 800 MHz.

关键词： low loss Z-type ferrites grain size antennas

A high-stability quasi-spherical resonator in SPRIGT for microwave frequency measurements at low temperatures

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Science Bulletin 2019年第5期64卷 286-288页

作者： Haiyang Zhang Wenjing Liu Bo Gao Yanyan Chen Changzhao Pan Yaonan Song Hui Chen Dongxu Han Jiangfeng Hu Ercang Luo Laurent Pitre TIPC-LNE Joint Laboratory on Cryogenic Metrology Science and Technology Chinese Academy of Sciences (CAS) Key Laboratory of Cryogenics Technical Institute of Physics and Chemistry (TIPC) Chinese Academy of Sciences (CAS) Laboratoire National de Métrologie Et d’essais-Conservatoire National des Arts et Métiers (LNE-Cnam) School of Mechanical Engineering Beijing Institute of Petrochemical Technology Key Laboratory of Thermo-Fluid Science and Engineering of MOE School of Energy and Power Engineering Xi’an Jiaotong University University of Chinese Academy of Sciences

To meet the de ma nds of high stability and sustainable temperature measurements over time,TIPC-CAS in China and LNE-Cnam in France have jointly developed single-pressure refractive-index gas thermometiy(SPR1GT),which... 详细信息

关键词： A high-stability quasi-spherical resonator SPRIGT microwave frequency measurements low temperatures