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Effects of loadinge-unloading and wettinge-drying cycles on geomechanical behaviors of mudrocks in the Colombian Andes

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Journal of Rock Mechanics and Geotechnical Engineering 2014年第3期6卷 257-268页

作者： Mario Camilo torres-Suarez Adolfo Alarcon-guzman Rafael Berdugo-de Moya National University of Colombia North University Barranquilla Colombia

The mudrocks in the Colombian Andes, particularly those exhibiting low cementation （bonding）, are susceptible to degradation when the environmental conditions change, which are challenging issues for engineering works. In this paper, the changes in physico-mechanical properties of mudrocks were moni- tored in laboratory, and some influential factors on the mechanical competence of geomaterials were studied. The geotechnical characteristics and experimental designs were developed from physical, chem- ical, mechanical and compositional points of view. In the tests, the techniques such as vapor equilibrium technique （VET） were employed to apply wetting-drying cycles and to control relative humidity （suction- controlled） and loading-unloading cycles through ultrasonic wave velocities technique. The results show that the main failure mechanisms for the laminated mudrocks start on the microscopic scale by fissures coalescence, exhibiting physico-chemical degradation as well; the global geomechanical behavior presents a state between a ductile, like rock, and a fragile, like soil. The obtained results can provide engineering values according to monitoring laboratory set, when compared with in situ conditions.

关键词： Mudrocksdegradation processesSuction changesStress-strain behaviorVapor equilibrium technique (VET)

Assessment of nutrients and conductivity in the Wachusett Reservoir watershed:An investigation of land use contributions and trends

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International Soil and Water Conservation Research 2024年第2期12卷 337-350页

作者： Amanda Carneiro Marques Carlos Eduardo Veras Emily Kumpel John E.Tobiason christian D.guzman dept of Civil and Environmental Engineering University of Massachusetts AmherstMA01003USA

The quality of drinking water for the Boston Metropolitan Area,supplied by the Quabbin-Wachusett system,is impacted by environmental *** objectives of this study are to increase understanding of the role that small streams may play in degradation of reservoir quality by characterizing seasonal constituent patterns from 1998 to 2020 in the Wachusett Reservoir watershed and by developing enhanced modeling *** monitoring(1998–2012)exhibited increased loads due to increasing flows despite declining solute *** present study analyzed seasonal nitrate(NO3)and total phosphorus(TP)concentration and load trends from 2012 to 2020 across 11 *** conductivity(SC)was also assessed to evaluate the impacts of road salt *** 2012 to 2020,statistical results for mean nutrient concentrations suggest static or declining temporal trends,while SC in all tributaries exhibited increasing *** use data suggest association with altered drainage landscapes as potential sources of increased constituent *** with the highest concentrations of TP,NO3,and SC have the largest percentage of impervious and cultivated areas,two to three times greater than other *** flows were modeled using the airGR hydrological model,subsequently used to calculate ***,flow magnitude was a more important load driver than long-term nutrient concentrations,thus,showing that stream discharge controlled load *** the other hand,persistently high SC levels controlled the increasing SC load ***,many nutrient reduction management strategies demonstrated an important impact from 1998 to *** watershed programs aimed at reducing salt applications,concentrations in streams are increasing,indicating a long-term legacy of salt *** smaller tributaries represent a modest portion of the system,addressing these sources has the potential to further reduce the long-term ecological

关键词： Water quality Nutrients Road salt Long-term trends Pollutant loading

A novel and stretchable carbon-nanotube/Ni@TiO_(2):W photocatalytic composite for the complete removal of diclofenac drug from the drinking water

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Journal of Environmental Sciences 2023年第4期126卷 575-589页

作者： Ernesto Valadez-Renteria Rafael Perez-Gonzalez christian Gomez-Solis Luis Armando Diaz-torres Armando Encinas Jorge Oliva Vicente Rodriguez-Gonzalez Consejo Nacional de Ciencia y Tecnología-División de Materiales Avanzados Instituto Potosino de Investigación Científica y TecnológicaSan Luis Potosí78216México División de Ciencias e Ingenierías Universidad de GuanajuatoLeón 37150México Grupo de Espectroscopia de Materiales Avanzados y Nanoestructurados(GEMANA) Centro de Investigaciones enópticaA.C.Lomas Del CampestreLeón 37150México

We present the structural,morphological and photocatalytic properties of stretchable composites made with carbon nanotubes (CNTs),silicon rubber and Ni@TiO_(2):W nanoparticles(TiWNi NPs) with average size of 37±2 *** images showed that the TiWNi NPs decorated the surface of the CNT fibers,which are oriented in a preferential *** NPs presented a mixture of anatase/rutile phases with cubic *** performance of the TiWNi powders and stretchable composites was evaluated for the photocatalytic degradation of diclofenac (DCF) anti-inflammatory drug under ultraviolet-visible *** results revealed that the maximum DCF degradation percentages were 34.6%,91.9%,97.1%,98.5%and 100%for the CNT composite (stretched at 0%),TiWNi powders,CNT+TiWNi(stretched at 0%),CNT+TiWNi (stretched at 50%) and CNT+TiWNi (stretched at 100%),***,stretching the CNT+TiWNi composites was a good strategy to enhance the DCF degradation percentage from 97.1%to 100%,since stretching created additional defects (oxygen vacancies) that acted as electron sink,delaying the electron-hole recombination,and favors the DCF ***/absorbance measurements confirmed the presence of such ***,the reactive oxygen species (ROS) were determined by the scavenger’s experiments and found that the main ROS were the·OH and O_(2)-radicals,which attacked the DCF molecules,causing their *** results of this investigation confirmed that the stretchable CNT/TiWNi-based composites are a viable alternative to remove pharmaceutical contaminants from water and can be manually separated from the decontaminated water,which is unviable using photocatalytic powders.

关键词： Diclofenac Pharmaceutical contaminant TiO_(2) Carbon nanotubes Stretchable composite Photocatalysis

depicting the battle between nectarine and Monilinia laxa:the fruit developmental stage dictates the effectiveness of the host defenses and the pathogen’s infection strategies

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Horticulture Research 2020年第1期7卷 619-633页

作者： Marta Balsells-Llauradó christian J.Silva Josep Usall Núria Vall-llaura Sandra Serrano-Prieto Neus Teixidó Saskia D.Mesquida-Pesci Antonieta de Cal Barbara Blanco-Ulate Rosario torres IRTA XaRTA-PostharvestEdifici FruitcentreParc Científic i Tecnològic Agroalimentari de Lleida25003 LleidaCataloniaSpain department of Plant Sciences University of CaliforniaDavisDavisCA 95616USA department of Plant Protection INIACtra.de La Coruña Km.728040 MadridCommunity of MadridSpain

Infections by the fungus Monilinia laxa,the main cause of brown rot in Europe,result in considerable losses of stone ***,we present a comprehensive transcriptomic approach to unravel strategies deployed by nectarine fruit and *** during their *** used ***-inoculated immature and mature fruit,which was resistant and susceptible to brown rot,respectively,to perform a dual RNA-Seq *** immature fruit,host responses,pathogen biomass,and pathogen transcriptional activity peaked at 14–24 h post inoculation(hpi),at which point *** appeared to switch its transcriptional response to either quiescence or *** fruit experienced an exponential increase in host and pathogen activity beginning at 6 *** analyses in both host and pathogen highlighted differences in stage-dependent *** example,in immature fruit,*** unsuccessfully employed carbohydrate-active enzymes(CAZymes)for penetration,which the fruit was able to combat with tightly regulated hormone responses and an oxidative burst that challenged the pathogen’s survival at later time *** contrast,in mature fruit,*** was more dependent on proteolytic effectors than CAZymes,and was able to invest in filamentous growth early during the *** analyses of mature fruit infected with *** indicated that,while jasmonic acid activity was likely useful for defense,high ethylene activity may have promoted susceptibility through the induction of ripening ***,we identified *** genes that were highly induced in both quiescent and active infections and may serve as targets for control of brown rot.

关键词： fruit pathogen strategies

Morphological Characterization and Hydrodynamic Behavior of Shortfin Mako Shark(Isurus oxyrinchus)Dorsal Fin denticles

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Journal of Bionic Engineering 2019年第4期16卷 730-741页

作者： Fernandez-Waid Patricia Diez guzman Bidaguren Inigo Izagirre Urtzi Blanco Jesus Maria Soto Manu department of Zoology and Animal Cell Biology Research Centre for Experimental Marine Biology and Biotechnology(PiE-UP V/EHU)University of the Basque CountryBilbao and Areatza z/gPlentzia 48620BizkaiaSpain Marine Research Division AZTITxatxarramendi s/n Sukarrieta 48395BizkaiaSpain department of Nuclear Engineering and Fluid Mechanics School of Engineering(UP V/EHU)University of the Basque CountryPlaza lngeniero Torres Quevedo 148013 BilbaoBizkaiaSpain

The shortfin mako shark(Isurus oxyrinchus)is one of the fastest marine fishes,reaching speeds of up to 70 km·h^-*** speed is related to the skin surface design composed of dermal *** vary in size and shape according to placement on the body and minimize turbulence around the *** objective of this study is to analyze the interaction between seawater flow and denticles on the dorsal ***-resolution microscopy(scanning electron microscopy and confocal microscopy)were used to measure defined parts of the dermal *** measurements,along with ratios based on length-to-width define three morphologies(rounded,semi-rounded,long)that were 3D *** fluid dynamics simulated fluid passage over reconstructed denticles and describe hy-drodynamic efficiency under different *** increase in angle of inclination produced a relevant increase in the drag coefficient,especially for high velocity *** lowest drag coefficient values were found in long and semi-rounded,followed by rounded *** hydrodynamic behavior of shark skin demonstrates a relation to the morphological characteristics of dermal denticles on the dorsal *** is concluded that the best hydroefficiency relies on the rounded morphology and may serve to design hydrodynamically efficient surfaces or manmade assemblies.

关键词： denticles hydrodynamic mako shark computational fluid dynamics

Feasibility study of minimally trained medical students using the Rural Obstetrical Ultrasound Triage Exam(ROUTE)in rural Panama

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World Journal of Emergency Medicine 2018年第3期9卷 216-222页

作者： Annasha Vyas Katherine Moran Joshua Livingston Savannah Gonzales Marlene torres Ali Duffens Carina Mireles Romo Gnevieve Mazza Briana Livingston Shadi Lahham John christian Fox School of Medicine University of California IrvineIrvineCA 92697USA department of Obstetrics and Gynecology University of California IrvineOrangeCA 92868USA department of Emergency Medicine University of California IrvineOrangeCA 92868USA

BACKGROUND:Maternal and infant mortality rates reported in rural Panama are greater than those in urban *** del Toro is a region of Panama inhabited by indigenous people at greater risk for pregnancy-related complications and deaths due to geographic isolation and limited access to health *** ultrasound training programs have recently been implemented in low-resource settings to increase access to diagnostic *** goal of this study is to determine the feasibility of teaching firstyear medical students the Rural Obstetrical Ultrasound Triage Exam(ROUTE)to help identify pathology in pregnant women of the Bocas del Toro region of ***:Eight first-year medical students completed ROUTE training *** training,the students were compared to professional sonographers to evaluate their accuracy in performing the *** then performed the ROUTE in mobile clinics within Bocas del *** enrolled women pregnant in their 2nd or 3rd trimesters and measured biparietal diameter,head circumference,amniotic fluid index,fetal lie and placental *** abnormal measurement would be further analyzed by the lead physician for a potential hospital ***:A total of 60 women were enrolled in the *** women were detected as having a possible high-risk pregnancy and thus referred to a hospital for further ***:Based on our data,first-year medical students with additional training can use the ROUTE to identify complications in pregnancy using ultrasound in rural *** studies are required to determine the optimal amount of training required for proficiency.

关键词： Point of care ultrasound Ultrasound education Rural Panama Obstetrics ultrasound

Assessment of clinical dehydration using point of care ultrasound for pediatric patients in rural Panama

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World Journal of Emergency Medicine 2019年第1期10卷 46-50页

作者： Genevieve Mazza Carina Mireles Romo Marlene torres Ali Duffens Annasha Vyas Katherine Moran Joshua Livingston Savannah Gonzales Shadi Lahham Inna Shniter Maxwell Thompson John christian Fox School of Medicine University of California Irvine department of Emergency Medicine University of California Irvine

BACKGROUND: dehydration and its associated symptoms are among the most common chief complaints of children in rural Panama. Previous studies have shown that intravascular volume correlates to the ratio of the diameters of the inferior vena cava(IVC) to the aorta(Ao). Our study aims to determine if medical students can detect pediatric dehydration using ultrasound on patients in rural Panama. METHODS: This was a prospective, observational study conducted in the Bocas del Toro region of rural Panama. Children between the ages of 1 to 15 years presenting with diarrhea, vomiting, or parasitic infection were enrolled in the study. Ultrasound measurements of the diameters of the IVC and abdominal aorta were taken to assess for dehydration. RESULTS: A total of 59 patients were enrolled in this study. Twenty-four patients were clinically diagnosed with dehydration and 35 were classified to have normal hydration status. Of the 24 patients with dehydration, half(n=12) of these patients had an IVC/Ao ratio below the American threshold of 0.8. Of the remaining asymptomatic subjects, about half(n=18) of these subjects also had an IVC/Ao ratio below the American threshold of ***: Our study did not support previous literature showing that the IVC/Ao ratio is lower in children with dehydration. It is possible that the American standard for evaluating clinical dehydration is not compatible with the rural pediatric populations of Panama.

关键词： Ultrasound Parasitic infection Panama Rural medicine dehydration Medical education

MEXICAN VACUUM STATIC EXPANSION SYSTEM （SEE-1）

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MEXICAN VACUUM STATIC EXPANSION SYSTEM （SEE-1）

Spectrum and visual outcomes of Vogt-Koyanagi-Harada disease in Argentina

国际压力与真空计量测试学术研讨会

作者： Santander L. A. torres-guzman J. C. Soriano J. B. Centro Nacional de Metrologia (CENAM Mexico) Centro Nacional de Metrologia （CENAM Mexico）Torres-Guzman J. C. Centro Nacional de Metrologia （CENAM Mexico）Soriano J. B Centro Nacional de Metrologia （CENAM Mexico）

＜正＞ The static expansion systems that are used to measure vacuum are considered primary standard systems. These systems are used to measure medium and high vacuum within the range of 1.10-5 Pa to 1.103 Pa absolute pressure. The Centro Nacional de Metrologia （CENAM, Mexico） has designed, constructed and characterized a primary system to be the vacuum national standard. This standard has been set up with the technical assistance of the Physikalisch Technische Bundesanstalt （PTB, Germany）.This paper presents the specifications of the system and the designing considerations in addition to some of the tests performed for its characterization. This constitutes the first primary standard for vacuum measurement in Latin America.

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International Journal of Ophthalmology(English edition) 2017年第1期10卷 98-102页

作者： Veronica E.Giordano Ariel Schlaen Martin J.guzman-Sanchez Cristobal Couto department of Ophthalmology Inflammatory Eye Diseases ServiceHospital de Clinicas Jose de San MartinBuenos Aires C1120AARArgentina department of Ophthalmology Oculoplastic ServiceAssociation for the Prevention of Blindness in MexicoVicente Garcia Torres 46San Lucas 04030CoyoacanMexico CityMexico

AIM： To review all cases of Vogt-Koyanagi-Harada （VKH） disease in an Inflammatory Eye Disease Service in Argentina and to describe the clinical profile and outcomes of ***： The records from patients with VKH disease between January 1980 and december 2008 were retrospectively analyzed for clinical profile, complications, and treatment. Patients were classified according to their initial treatment in group 1： high corticosteroid dose [≥1 mg/（kg·d）] within 2wk of illness onset; group 2： high corticosteroid dose, 2 to 4wk of onset and group 3： patients who received the high dose after 1mo of illness onset, patients who received lower oral doses than 1 mg/（kg·d） without regarding the time of beginning of the ***： A total of 210 eyes of 105 patients were included. The mean age at presentation was 32.6±13y （range： 10-74y）, and 86.7% were female. The mean duration of follow up was 144±96.6mo. Patients in the group 1 had significantly higher visual acuity than the other groups （P〈0.0001）, none had （loss of, or no） light perception at the end of follow up, whereas 24.7% patients in group 3 ended in light perception （P〈0.004）.CONCLUSION： Patients with early high dose corticosteroid treatment have better visual acuity and fewer complications. Proper timing in referral and treatment is critical for better visual outcome in VKH disease.

关键词： Vogt-Koyanagi-Harada disease Argentine population clinical spectrum treatment