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A novel IDEA: the impact of serial interval on a modified- Incidence Decay and Exponential Adjustment (m-IDEA) model for projections of daily COVID-19 cases

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Infectious Disease Modelling 2020年第1期5卷 346-356页

作者： ben A.Smith Public Health Risk Sciences Division National Microbiology LaboratoryPublic Health Agency of Canada370 Speedvale Ave W.GuelphONN1H 7M7Canada

the SARS-CoV-2 virus causes the disease COVID-19,and has caused high morbidity and mortality *** models are useful tools to predict future trends of disease progression such as COVID-19 over the near-term.A modified Incidence Decay and Exponential Adjustment(m-IDEA)model was developed to predict the progression of infectious disease *** modification allows for the production of precise daily estimates,which are critical during a pandemic of this scale for planning *** m-IDEA model was employed using a range of serial intervals given the lack of knowledge on the true serial interval of *** deterministic and stochastic approaches were *** fitting was accomplished through minimizing the sum-of-square differences between predicted and observed daily incidence case counts,and performance was retrospectively *** performance of the m-IDEA for projection cases in the nearterm was improved using shorter serial intervals(1e4 days)at early stages of the pandemic,and longer serial intervals at mid-to late-stages(5e9 days)thus ***,coupled with epidemiological reports,suggests that the serial interval of COVID-19 might increase as the pandemic progresses,which is rather intuitive:Increasing serial intervals can be attributed to gradual increases in public health interventions such as facility closures,public caution and social distancing,thus increasing the time between transmission *** most cases,the stochastic approach captured the majority of future reported incidence data,because it accounts for the uncertainty around the serial interval of *** such,it is the preferred approach for using the m-IDEA during dynamic situation such as in the midst of a major pandemic.

关键词： Forecasting/methods Models Statistical Communicable diseases/epidemiology SARS coronavirus-2 COVID-19

Adsorption behavior of sulfamethazine in an activated sludge process treating swine wastewater

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journal of Environmental Sciences 2014年第8期26卷 1623-1629页

作者： Weiwei ben Zhimin Qiang Xiaowei Yin jiuhui Qu Xun Pan Key Laboratory of Aquatic Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of Sciences Foreign Economic Cooperation Office Ministry of Environmental Protection

Swine wastewater is an important pollution source of antibiotics entering the aquatic environment. In this work,the adsorption behavior of sulfamethazine（SMN）,a commonlyused sulfonamide antibiotic,on activated sludge from a sequencing batch reactor treating swine wastewater was investigated. the results show that the adsorption of SMN on activated sludge was an initially rapid process and reached equilibrium after 6 hr. the removal efficiency of SMN from the water phase increased with an increasing concentration of mixed liquor suspended solids,while the adsorbed concentration of SMN decreased. Solution pH influenced both the speciation of SMN and the surface properties of activated sludge,thus significantly impacting the adsorption process. A linear partition model could give a good fit for the equilibrium concentrations of SMN at the test temperatures（i.e.,10,20 and 30°C）. the partition coefficient（Kd） was determined to be 100.5 L/kg at 20°C,indicating a quite high adsorption capacity for SMN. thermodynamic analysis revealed that SMN adsorption on activated sludge was an exothermic process. this study could help to clarify the fate and behavior of sulfonamide antibiotics in the activated sludge process and assess consequent environmental risks arising from sludge disposal as well.

关键词： Sulfonamide antibiotics Activated sludge Adsorption Swine wastewater treatment

Genetic Transformation of Tobacco with the Trehalose Synthase Gene from Grifola frondosa Fr. Enhances the Resistance to Drought and Salt in Tobacco

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journal of Integrative Plant Biology 2005年第5期47卷 579-587页

作者： Shu-ZhenZHANG ben-PengYANG Cui-LianFENG Huo-LongTANG InstituteofTropicalBiotechnology ChineseAcademyofTropicalAgriculturalSciencesHaikou571101China StateKeyLaboratoryofTropicalCropBiotechnology ChineseAcademyofTropicalAgriculturalSciencesHaikou571101China／／InstituteofTropicalBiotechnologyChineseAcademyofTropicalAgriculturalSciencesHaikou571101China

Trehalose is a non-reducing disaccharide of glucose that functions as a protectant in the stabilization of biological structures and enhances the tolerance of organisms to abiotic stress. In the present study, we report on the expression of the Grifola frondosa Fr. Trehalose synthase (Tsase) gene for manipulating abiotic stress tolerance in tobacco (Nicotiana tabaccum L.). the expression of the transgene was under the control of two tandem copies of the CaMV3 5 S promoter and was transferred into tobacco by Agrobacterium tumefaciens EHA105. Compared with non-transgenic plants, transgenic plants were able to accumulate high levels of products of trehalose, which were increased up to 2.126–2.556 mg/g FW, although levels were undetectable in non-transgenic plants. this level of trehalose in transgenic plants was 400-fold higher than that of transgenic tobacco plants cotransformed with Escherichia coli TPS and TPP on independent expression cassettes, twofold higher than that of transgenic rice plants transformed with a bi functional fusion gene (TPSP) of the trehalose-6-phosphate (T-6-P) synthase (TPS) and T-6-P phosphatase (TPP) of E. coli, and 12-fold higher than that of transgenic tobacco plants transformed the yeast TPS1 gene. It has been reported that transgenic plants with E. coli TPS and/or TPP were severely stunted and had morphological alterations of their roots. Interestingly, our transgenic plants have obvious morphological changes, including thick and deep-coloured leaves, but show no growth inhibition; moreover, these morphological changes can restore to normal type in T2 progenies. Trehalose accumulation in 35S–35S:Tsase plants resulted in increased tolerance to drought and salt, as shown by the results of tests on drought, salt tolerance, and drought physiological indices, such as water content in excised leaves, malondialdehyde content, chlorophyll a and b contents, and the activity of superoxide dismutase and peroxidase in excised leaves. these results

关键词： drought and salt tolerance genetic transformation Grifola frondosa Fr. Nicotiana tabaccum L. trehalose synthase gene

Structural Morphological and Optical Properties of SnSb_2S_4 thin Films Grown by Vacuum Evaporation Method

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journal of Materials Science & Technology 2014年第10期30卷 1006-1011页

作者： N.Khedmi M.ben Rabeh M.Kanzari Laboratoire de Photovoltaques et Matriaux de Semi-conducteurs-ENIT-Universit de Tunis el Manar BP 37le belvedere1002 TunisTunisie Laboratoire de Photovoltaques et Matriaux de Semi-conducteurs-ENIT-IPEITunis Montfleury-Universit de Tunis Tunisie

SnSb2S4 thin films were prepared from powder by thermal evaporation under vacuum of 1.33 × 10^-4 Pa （ 10^-6 Torr） on unheated glass substrates. the effect of thickness on the structural, morphological and optical properties of SnSb2S4 thin films was investigated. Films thickness measured by interference fringes method varied from 50 to 700 nm. X-ray diffraction analysis revealed that all the SnSb2S4 films were polycrystalline in spite without heating the substrates and the crystallinity was improved with increasing film thickness. the microstructure parameters： crystallite size, strain and dislocation density were calculated. It was observed that the crystallite size increased and the crystal defects decreased with increasing film thickness. In addition, by increasing the film thickness, an enhancement in the surface roughness root-mean-square （RMS） increased from 2.0 to 6.6 nm. the fundamental optical parameters like band gap, absorption and extinction coefficient were calculated in the strong absorption region of transmittance and reflectance spectrum. the optical absorption measurements indicated that the band （Eg） gap of the thin films decreased from 2.10 to 1.65 eV with increasing film thickness. the refractive indexes were evaluated in transparent region in terms of envelope method, which was suggested by Swanepoul. It was observed that the refractive index increased with increasing film thickness.

关键词： Ternary system thermal evaporation technique thin films thickness Atomic force microscopy (AFM)

Accumulation of polybrominated diphenyl ethers in breast milk of women from an e-waste recycling center in China

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journal of Environmental Sciences 2017年第2期29卷 305-313页

作者： Xinghong Li Yuan Tian Yun Zhang Yujie ben Quanxia Lv State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center of Eco-Environment SciencesChinese Academy of Sciences Department of Environmental Science and Engineering Beijing Technology and Business University

Polybrominated diphenyl ethers（PBDEs） can be transferred to infants through the ingestion of breast milk, resulting in potential health risk. In this study, PBDEs, hydroxylated polybrominated diphenyl ethers（OH-PBDEs） and 2,2′,4,4′,5,6′-hexachlorobiphenyl（CB-153）in human milk from women living adjacent to e-waste recycling sites of Wenling,China, were investigated. the median level of PBDEs in samples from residents living in the e-waste recycling environment 〉 20 years（R20group, 19.5 ng/g lipid weight（lw））was significantly higher than that for residents living in Wenling 〈 3 years（R3group,3.88 ng/g lw）（p 〈 0.05）, likely ascribable to specific exposure to PBDEs from e-waste recycling activities. In the R20 group, most congeners（except for BDE-209） were correlated with each other（p 〈 0.05）. Moreover, CB-153 showed significant association with most PBDE congeners, rather than BDE-209. the relationship indicated that most BDE congeners other than BDE-209 shared common sources and/or pathways with CB-153, e.g., dietary ingestion. the correlations between BDE-209 and other congeners were different in the two groups, likely suggesting their different exposure sources and/or pathways for *** estimated dietary intake of PBDEs for infants via breast milk was lower than the minimum value affecting human health, the PBDE exposure of infants should be of great concern because of their potential effect on the development of neonates over long-term exposure. OH-PBDEs were not detected in the collected samples, which is in accordance with reports in published literature, likely indicating that they were not apt to be accumulated in human milk.

关键词： PBDEs OH-PBDEs Human milk E-waste

Rapid detection of multiple class pharmaceuticals in both municipal wastewater and sludge with ultra high performance liquid chromatography tandem mass spectrometry

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journal of Environmental Sciences 2014年第9期26卷 1949-1959页

作者： Xiangjuan Yuan Zhimin Qiang Weiwei ben Bing Zhu junxin Liu Key Laboratory of Aquatic Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of Sciences

this work described the development, optimization and validation of an analytical method for rapid detection of multiple-class pharmaceuticals in both municipal wastewater and sludge samples based on ultrasonic solvent extraction, solid-phase extraction, and ultra high performance liquid chromatography-tandem mass spectrometry quantification. the results indicated that the developed method could effectively extract all the target pharmaceuticals （25） in a single process and analyze them within 24 min. the recoveries of the target pharmaceuticals were in the range of 69%-131% for wastewater and 54%-130% for sludge at different spiked concentration levels. the method quantification limits in wastewater and sludge ranged from 0.02 to 0.73 ng/L and from 0.02 to 1.00μg/kg, respectively. Subsequently, this method was validated and applied for residual pharma- ceutical analysis in a wastewater treatment plant located in Beijing, China. All the target pharmaceuticals were detected in the influent samples with concentrations varying from 0.09 ng/L （tiamulin） to 15.24 μg/L （caffeine）; meanwhile, up to 23 pharmaceuticals were detected in sludge samples with concentrations varying from 60 ng/kg （sulfamethizole） to 8.55 mg/kg （ofloxacin）. the developed method demonstrated its selectivity, sensitivity, and reliability for detecting multiple-class pharmaceuticals in complex matrices such as municipal wastewater and sludge.

关键词： PharmaceuticalsUltrasonic solvent extractionSolid phase extractionUPLC-MS/MSMunicipal wastewaterSludge

Quantification and depth distribution analysis of carbon to nitrogen ratio in forest soils using reflectance spectroscopy

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International Soil and Water Conservation Research 2023年第1期11卷 112-124页

作者： Asa Gholizadeh Mohammadmehdi Saberioon Nastaran Pouladi Eyal ben-Dor Department of Soil Science and Soil Protection Faculty of AgrobiologyFood and Natural ResourcesCzech University of Life Sciences Prague16500PragueCzech Republic Section 1.4 Remote Sensing and Geoinformatics Helmholtz Centre Potsdam GFZ German Research Centre for GeosciencesTelegrafenberg14473Potsdam Germany knoell Germany GmbH Konrad-Zuse-Ring68163MannheimGermany Remote Sensing Laboratoryeparmentof Ggraphy and HumanEnvionmnt Porter Schoolf Evionmntand Earth ScienceTelAvivUniverty 69978TelAvivIsrael

Forest soils have large contents of carbon(C)and total nitrogen(TN),which have significant spatial variability laterally across landscapes and vertically with depth due to decomposition,erosion and ***,the ratio of C to TN contents(C∶N),a crucial indicator of soil quality and health,is also different depending on soil *** attributes can cost-effectively and rapidly be estimated using visible-near infrared-shortwave infrared(VNIR-SWIR)***,the effect of different soil layers,particularly over large scales of highly heterogeneous forest soils,on the perfor-mance of the technique has rarely been *** study evaluated the potential of VNIR-SWIR spectroscopy in quantification and variability analysis of C∶N in soils from different organic and min-eral layers of forested sites of the Czech *** each site,we collected samples from the litter(L),fragmented(F)and humus(H)organic layers,and from the A_(1)(depth of 2-10 cm)and A_(2)(depth of 10-40 cm)mineral layers providing a total of 2505 *** vector machine regression(SVMR)was used to train the prediction models of the selected attributes at each individual soil layer and the merged layer(profile).We further produced the spatial distribution maps of C∶N as the target attribute at each soil *** showed that the prediction accuracy based on the profile spectral data was adequate for all ***,F was the most accurately predicted layer,regardless of the soil attribute.C∶N models and maps in the organic layers performed well although in mineral layers,models were poor and maps were reliable only in areas with low and moderate C∶*** the other hand,the study indicated that reflectance spectra could efficiently predict and map organic layers of the forested ***,in mineral layers,high values of C∶N(≥50)were not detectable in the map created based on the reflectance *** general,the study suggests that VNIR-SWIR spectrosc

关键词： Forest soil Soilorganiccarbon C:N Soilhorizons VNIR-SWIRspectroscopy

Strategic mining options optimization:Open pit mining, underground mining or both

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International journal of Mining Science and Technology 2016年第6期26卷 1065-1071页

作者： ben-Awuah Eugene Richter Otto Elkington Tarrant Pourrahimian Yashar Bharti School of Engineering Laurentian University Mining Department Snowden Mining Industry Consultants School of Mining and Petroleum Engineering University of Alberta

Near-surface deposits that extend to considerable depths are often amenable to both open pit mining and/or underground mining. this paper investigates the strategy of mining options for an orebody using a Mixed Integer Linear Programming(MILP) optimization framework. the MILP formulation maximizes the Net Present Value(NPV) of the reserve when extracted with(i) open pit mining,(ii) underground mining, and(iii) concurrent open pit and underground mining. Comparatively, implementing open pit mining generates a higher NPV than underground mining. However considering the investment required for these mining options, underground mining generates a better return on investment than open pit mining. Also, in the concurrent open pit and underground mining scenario, the optimizer prefers extracting blocks using open pit mining. Although the underground mine could access ore sooner, the mining cost differential for open pit mining is more than compensated for by the discounting benefits associated with earlier underground mining.

关键词： Mining options optimization Open pitUnderground Concurrent Open stope Mixed Integer Linear Programming (MILP)

Mind the “Gap”: A Comparison of the Weekly Training Loads of English Premier League Academy Soccer Players in Under 23, Under 18 and Under 16 Age-Groups

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journal of Science in Sport and Exercise 2023年第1期5卷 34-43页

作者： jonathan M.Taylor jonathan L.Madden Frances Hunter ben j.th.rne Shaun j.McLaren School of Health and Life Sciences Teesside UniversityMiddlesbroughUK Leeds United Football Club LeedsUK Middlesbrough Football Club MiddlesbroughUK Hintsa Performance LondonUK Department of Sport and Exercise Sciences Durham UniversityDurhamUK

Purpose the transition into full-time training represents a key period in the development of young soccer *** we compared the weekly training loads(matches,field-,and resistance-training)of English Premier-League Academy soccer players from under-16(U16),under-18(U18)and under-23(U23)age-groups during a training *** Forty players(U16 n=13,U18 n=15 and U23 n=12)were monitored using global navigation satellite systems and differential ratings of perceived exertion(dRPE).External load metrics were total distance,high-speed running distance,[absolute:≥19.8 km/h,relative:≥87%of 30-15 final-velocity(vIFT)],sprint distance(absolute:≥25.2 km/h,relative:≥80%maximal sprint speed),and dynamic stress *** load metrics were dRPE training *** Other than relative sprint distance,overall weekly external training loads were substantially greater for U18s and U23s when compared with U16s[effect size range:1.09-1.99(moderate to large);±90%confidence limits~0.45].When compared with U16s,overall internal loads were substantially greater for U18s[0.69-0.95(moderate);±~0.40],but not *** in weekly training loads between U18s and U23s were *** Substantial differences in training loads between elite U16 players and their older counterparts,indicates the need for planned increases in training loads in anticipation of the transition into full-time training.

关键词： Team-sports RPE LTAD Individualised training Training load