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Identifying Nonpoint Sources of Phosphorus and Nitrogen: A Case Study of Pollution That Enters a Freshwater Wetland (Laguna Cartagena, Puerto Rico)

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Journal of Water Resource and Protection 2021年第8期13卷 588-604页

作者： Yashira Marie Sánchez-colón Fred Charles Schaffner Public Health Program Ponce Health Sciences University Ponce Puerto Rico School of Science and Technology Ana G. Méndez University Gurabo Puerto Rico

Point and nonpoint sources of phosphorus (P) and nitrogen (N) can cause reductions in water quality, including eutrophication. Nonpoint pollution represents a special challenge because of dispersed not easily identifiable sources such as the runoff from soil, nutrients, and other chemicals from agricultural fields and residential areas. Laguna Cartagena is a tropical freshwater wetland, situated in southwestern Puerto Rico. It is a eutrophic ecosystem, and its eutrophication is caused by both external nutrient loading and internal, mainly by phosphorus. This wetland has been affected by phosphorus loading from inorganic agricultural fertilizer in this historically oligotrophic wetland system until the end of subsidized fertilizer use and sugar cane cultivation in the late 1990s. This study identifies: 1) nonpoint sources of phosphorus (SRP, Soluble Reactive Phosphorus and TP, Total Phosphorus) and nitrogen (nitrate, nitrite, and ammonia) that enter Laguna Cartagena;and 2) the role of precipitation events on the contributions of phosphorus and nitrogen loading to ecosystems. Herein we assess water samples from five channelized external sources of P and N that enter Laguna Cartagena at two-week intervals from October 2013 through November 2014. Rainfall data were obtained weekly from a rain gauge. Standard methods were used for all chemical analyses. Results showed that the channelized waterways that carry water to the lagoon can be classified as hypereutrophic (>100 μg/L) for TP concentrations and oligotrophic (<200 μg/L) for nitrogen concentrations. Currently agriculture (rice and cattle) is the predominant land use at the nearby University of Puerto Rico (UPR) Lajas Agricultural Experiment Substation, the predominant nonpoint source of nutrient pollution (SRP, TP and ammonia) in the principal channelized water sources to the lagoon. Current nutrient loads are likely derived from fertilizers applied to the Substation’s rice fields, and a high density livestock. The

关键词： Nonpoint Sources Soluble Reactive Phosphorus Total Phosphorus Nitrogen Depleted Eutrophication

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Does drought stress modify the effects of plant-growth promoting rhizobacteria on an aboveground chewing herbivore？

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Insect Science 2017年第6期24卷 1034-1044页

作者： Maite Fernandez de Bobadilla Julia Friman Nurmi Pangesti Marcel Dicke Joop J.A. van Loon ana Pineda Laboratory of Entomology Wageningen University Wageningen The Netherlands Netherlands Institute of Ecology (NIOO-KNA W) Department of Terrestrial Ecology Wageningen The Netherlands

Soil microbes have important effects on the interactions of plants with their environment, by promoting plant growth, inducing resistance to pests or by conferring tolerance to abiotic stress. However, their effects are variable and the factors responsible for this variation are mainly unknown. Our aim was to assess how drought stress modifies the effect of the nonpathogenic rhizobacterium Pseudomonas simiae WCS417r on plant growth and resistance against the generalist leaf-chewing caterpillar Mamestra brassicae. We studied Arabidopsis tha/iana col-0 plants, as well as mutants altered in the biosyn- thesis of the phytohormones jasmonic acid （JA） and abscisic acid （ABA）. Caterpillars did not prefer rhizobacteria-treated plants, independently of drought stress. Rhizobacteria colonization had a variable effect on caterpillar performance, which ranged from positive in one experiment to neutral in a second one. Drought had a consistent negative effect on herbivore performance; however, it did not modify the effect of rhizobacteria on herbivore performance. The effect of drought on herbivore performance was JA-mediated （confirmed with the use of the dde2-2 mutant）, but it was still present in the ABA-deficient mutant aba2-1. Plant biomass was reduced by both drought and herbivory but it was enhanced by rhizobacterial colonization. Pseudomonas simiae WCS417r is able to promote plant growth even when plants are suffering herbivory. Nevertheless, the microbial effect on the herbivore is variable, independently of drought stress. To get the best possible outcome from the rhizobacteria-plant mutualism it is important to understand which other factors may be responsible for its context-dependency.

关键词： abiotic stress abscisic acid crosstalk induced systemic resistance jasmonic acid Pseudomonas simiae

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Natural variability of essential oil and antioxidants in the medicinal plant Turnera diffusa

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Asian Pacific Journal of Tropical Medicine 2017年第2期10卷 114-119页

作者： ana Lucía Urbizu-González Octelina Castillo-Ruiz Guillermo Cristian Guadalupe Martínez-Ávila Jorge Ariel Torres-Castillo Universidad Autónoma de Tamaulipas Instituto de Ecología AplicadaDivisión del Golfo 356Col.Libertad87019Ciudad VictoriaTamaulipasMéxico Universidad Autónoma de Tamaulipas Unidad Académica Multidisciplinaria Reynosa AztlánCalle 16 y Lago de Chápala s/n Col.AztlánC.P.88740ReynosaTamaulipasMéxico Universidad Autónoma de Nuevo León Facultad de AgronomíaFrancisco Villa s/n.Col.Ex Hacienda El Canadá66050General EscobedoNuevo LeónMéxico

Objective:To evaluate differences in yield and composition of the essential oil and antioxidant contents in *** plants from localities in central region of ***:Samples were collected in Tamaulipas,Mexico in the arid *** oil was obtained through steam distillation and analyzed using *** contents,antioxidant activities using ABTS and ferric reducing antioxidant power(FRAP) methods also were ***:A total of 21 compunds were identified in the essential oils;nevertheless,only Eucalyptol,1,4-Methanocycloocta[d]pyridazine,1,4,4a,5,6,9,10,10a-octahydro-11,11-dimethyl-,(1à,4à,4aà,10aà) y Ethanone,1-(1,3-dimethyl-3-cyclohexen-1-yl) were detected in the three *** contents were registered in the sample from Padrón y Juárez with phenolic content of 33.85 mg GAE/g of dry material and antioxidant activities with ABTS 72.32% and with FRAP 21.33 mg GAE/g of dry *** differences were observed in essential oil,phenolics and antioxidants contents between ***:Results suggest that climatic differences and origin influence the phytochemicals in the medicinal plant ***,and thus,it is worth to consider such effects for industrial and medicinal purposes.

关键词： Essential oil Antioxidants Phytochemicals Chemical variation

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Retrospective study of HIV drug resistance in Mexican children with vertically transmitted infection

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World Journal of Pediatrics 2022年第7期18卷 505-510页

作者： Cristina de Jesus Herrera-Castillo Angelica Maldonado-Rodriguez Othon Rojas-Montes ana Maria Cevallos JoséGuillermo Vazquez-Rosales Rosalia Lira Infectious Diseases Department Pediatrics Hospital"Silvestre Frenk Freund"National Medical Center"Siglo ⅩⅪ".Mexican Social Sccurity Instiute(IMSS).Mexico City.Mexico Infectious and Parasitie Dise ases Medical Research Unit Pediatrics Hospital"Silvestre Frenk Freund"National Medical Center“Siglo ⅩⅪ”Mexican Social Security Institute(IMSS).Col.Cuauhtemoc.Av.Cuauhtemoc 33006720 Mexico CityMexico Departament of Molecular Biology and Biotechnology Biomedical Research InstituteNational Autonomous University of MexicoUNAMMexico City.Mexico

According to World Health Organization(WHO)estimates,in 2020,there were 1.8 million human immunodeficiency virus(HIV)-infected children below 15 years old living with HIV and 150,000 children who acquired the infection[1].Every year,110,000 children die as a consequence of acquired immune deficiency syndrome-related causes[2].As in adults,optimal management of infected children depends on early diagnosis and treatment with antiretroviral drugs based on their viral genotype.

关键词： infection diagnosis drugs

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Correlation of different imaging modalities in pre-surgical evaluation of pericardial metastasis of liposarcoma

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Chinese Medical Journal 2012年第20期125卷 3752-3754页

作者： Zeljko Z Markovic ana Mladenovic Marko Banovic Branislava Ivanovic Radiology ClinicUniversity Clinical Center of Serbia Pasterova 2BelgradeSerbia Cardiology Clinic University Clinical Center of SerbiaPasterova 2BelgradeSerbia

A patient presented with a large pericardial tumor of uncertain etiology. Five years earlier, she had been treated for myxoid liposarcoma of the thigh. For pre-surgical evaluation, conventional radiography, positron emission tomography/computed tomography （PET/CT）, magnetic resonance imaging （MRI）, CT of the heart, transthoracic echocardiography （tte） and transesophageal echocardiography （TEE） were performed. The final histopathologic diagnosis was metastatic liposarcoma. Each of the imaging modalities used had advantages and disadvantages, and their coordination was necessary for optimal evaluation.

关键词： liposarcoma pericardial metastasis," imaging modality

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High plasma levels of col10A1 are associated with advanced tumor stage in gastric cancer patients

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World Journal of Gastroenterology 2020年第22期26卷 3024-3033页

作者： Laura Necula Lilia Matei Denisa Dragu Ioana Pitica ana Iulia Neagu Coralia Bleotu Simona Dima Irinel Popescu Carmen C Diaconu Mihaela Chivu-Economescu Department of Cellular and Molecular Pathology Stefan S.Nicolau Institute of VirologyBucharest 030304Romania Titu Maiorescu University Faculty of MedicineBucharest 040441Romania Fundeni Clinical Institute Bucharest 022328Romania

BACKGROUND Gastric cancer(GC)remains an aggressive malignancy with a high rate of mortality,being the third leading cause of cancer-related *** than one million newly diagnosed cases and 782685 deaths due to GC were reported in *** is characterized by limited effective treatment options and the lack of consistent biomarkers for the diagnosis and prognosis of these *** discovery of new biomarkers useful in the early diagnosis of GC is *** To evaluate the potential of col10A1 as a circulating biomarker for the diagnosis and prognosis of gastric adenocarcinoma *** Plasma and tissue obtained from 49 patients with gastric adenocarcinoma have been used in exploring the expression of ***-time PCR and western blot techniques were used to evaluate col10A1 level in gastric tumor tissue compared to normal adjacent *** circulating level of col10A1 was also evaluated by ELISA in plasma of gastric adenocarcinoma *** analysis was made in order to evaluate the potential of col10A1 as a biomarker for the diagnosis and prognosis of gastric adenocarcinoma *** Our results showed a significant increase in col10A1 gene expression and protein levels in gastric tumor tissue compared to adjacent normal tissue(Pcol10A1 seems to show an elevated expression from the beginning of carcinogenesis,in the early stages,and its increased level remains elevated during cancer progression.A significant increase of col10A1 plasma level in gastric adenocarcinoma patients was also ***,increased col10A1 plasma level was associated with poor survival of the *** col10A1 performed a diagnostic value in GC with area under the receiver operating characteristic curve(AUC)of 0.9171(P=0.0002),sensitivity of 87.76%,and specificity of 100.0%.Furthermore,this study demonstrated the potential role of plasma col10A1 in the early detection of GC,as in the early stage,we obtained an AUC of 0.8789(P=0.00

关键词： Gastric cancer col10A1 Circulating biomarkers Early diagnosis Poor prognosis Tumor stage

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An Assessment of Water Quality Parameters at the Cerrillos Reservoir, Ponce, Puerto Rico in the Aftermath of Hurricane Maria

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Journal of Water Resource and Protection 2022年第1期14卷 35-49页

作者： Yashira Marie Sánchez-colón Javier Alejandro Chévere-Del Río Nichole Marie Sánchez-Guzmán Fred Charles Schaffner Public Health Program Ponce Health Sciences University Ponce Puerto Rico Puerto Rico Department of Health San Juan Puerto Rico School of Science and Technology Universidad Ana G Méndez Gurabo Campus Gurabo Puerto Rico

Maintaining the water quality of lakes and reservoirs is part of the 2030 Agenda for Sustainable Development, an initiative promoted by the United Nations, including anthropogenic and natural factors that may influence water quality. The water reservoirs of Puerto Rico were built in watersheds to provide runoff control and for primary uses. The Cerrillos Reservoir is one of the largest water reservoirs in southern Puerto Rico, and is used as a source of potable water and for recreational activities. After hurricane Maria, in September 2017, many communities were without public water service and have obtained their drinking water from local rivers or their tributaries, without filtration or purification treatment. This research explored the physical-chemical parameters of Cerrillos Reservoir’s surface water from May 2018 to January 2019. The objective of the present study is to assess seasonal variations in surface water quality with respect to physical (temperature, turbidity, and conductivity), chemical (nutrient concentrations: (Phosphorus (P) (Soluble Reactive Phosphorus, phosphate, or orthophosphate) and Nitrogen (N) (nitrate, nitrite, and ammonia)), pH, and dissolved oxygen), and biological (total coliforms and Escherichia coli) parameters. Results suggest that Cerrillos Reservoir did not exceed the parameters of temperature, turbidity, conductivity, pH and DO, established by the Puerto Rico Department of Natural and Environmental Resources (PRDNER). The reservoir showed a stable trophic state in relation to inorganic phosphorus and nitrogen as N and P concentrations did not increase sufficiently to disrupt this ecosystem. However, total coliforms exceeded the maximum parameter (23 MPN/100mL - 994 MPN/100mL) established for the Puerto Rico Department of Natural and Environmental Resources and are likely to be the results of the disruption caused by hurricane Maria.

关键词： Cerrillos Reservoir Water Quality Puerto Rico Post Hurricane Maria

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Portal hypertensive colopathy is associated with portal hypertension severity in cirrhotic patients

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World Journal of Gastroenterology 2009年第38期15卷 4781-4787页

作者： Antonio Diaz-Sanchez Oscar Nuez-Martinez Cecilia Gonzalez-Asanza ana Matilla Beatriz Merino Diego Rincon Inmaculada Beceiro Maria Vega Catalina Magdalena Salcedo Rafael Baares Gerardo Clemente Liver Unit-CIBEREHD.Hospital General Universitario Gregorio Maraón Madrid 28007Spain Gastroenterology Unit Hospital Infanta Leonor Gastroenterology Unit Hospital Infanta Sofia Department of Gastroenterology Hospital Universitario Príncipe de Asturias

AIM： To assess the prevalence of portal hypertension （PH） related colorectal lesions in liver transplant candidates, and to evaluate its association with the severity of PH. METHODS： Between October 2004 and December 2005, colonoscopy was performed in 92 cirrhotic liver transplant candidates. We described the lesions resulting from colorectal PH and their association with the grade of PH in 77 patients who underwent measurement of hepatic venous pressure gradient （HVPG）. RESULTS： Mean age was 55 years and 80.7% of patients were men. The main etiology of cirrhosis wasalcoholism （45.5%）. Portal hypertensive colopathy （PHC） was found in 23.9%, colonic varices in 7.6% and polyps in 38% of patients （adenomatous type 65.2%）. One asymptomatic patient had a well-differentiated adenocarcinoma. The manifestations of colorectal PH were not associated with the etiology of liver disease or with the Child-Pugh grade. Ninety percent of patients with colopathy presented with gastroesophageal varices （GEV）, and 27.5% of patients with GEV presented with colopathy （P = 0.12）. A relationship between higher values of HVPG and presence of colopathy was observed （19.9：1：6.2 mmHg vs 16.8 ± 5.4 mmHg, P = 0.045）, but not with the grade of colopathy （P = 0.13）. Preneoplastic polyps and neoplasm （P = 0.02） and spontaneous bacterial peritonitis （P = 0.006） were more prevalent in patients with colopathy. We did not observe any association between previous β-blocker therapy and the presence of colorectal portal hypertensive vasculopathy. CONCLUSION： PHC is common in cirrhotic liver transplant candidates and is associated with higher portal pressure.

关键词： Liver cirrhosis Portal hypertension Polyps colopathy Liver transplantation

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Non-linear modeling of kinetic and equilibrium data for the adsorption of hexavalent chromium by carbon nanomaterials:Dimension and functionalization

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Chinese Journal of Chemical Engineering 2019年第4期27卷 912-919页

作者： Miguel de la Luz-Asunción Eduardo E.Pérez-Ramírez ana L.Martínez-Hernández Victor M.Castano Víctor Sánchez-Mendieta Carlos Velasco-Santos Facultad de Quimica Universidad Autonoma del Estado de Mexico Km. 12 de la carretera Toluca-Atlacomulco C.P. 50200 San Cayetano Toluca Estado de Mexico Mexico Tecnologico Nacional de Mexico-Instituto Tecnologico de Queretaro Division de Estudios de Posgrado e Investigacion Av. Tecnologico s/n esq. GraL Mariano Escobedo Col. Centro Historico C.P. 76000 Santiago de Queretaro Queretaro Mexico Centro de Fisica Aplicada y Tecnologia Avanzada Universidad Nacional Autonoma de Mexico Boulevard Juriquilla 3001 Queretaro 76230 Mexico

The adsorption capacities for the removal of hexavalent chromium from aqueous solutions by six carbon nanomaterials have been evaluated. Single-walled and multi-walled carbon nanotubes as received and after oxidation treatment, graphene oxide and reduced graphene oxide are the materials with different dimension and functionalization compared in this research. Carbon nanotubes have been modified using hydrogen peroxide as oxidizing agent under microwave radiation. The oxidation treatment on carbon nanotubes has a positive effect increasing the adsorbent–adsorbate interaction. Rate-controlling mechanisms and equilibrium data are analyzed using non-linear models. Non-linear method is proposed as the most suitable method for determining the kinetic and equilibrium parameters. The values of adsorption energy(E) obtained from the Dubinin–Radushkevich isotherm,have been found around 0.371 and 0.870 k J·mol-1, indicating physical adsorption. Therefore, the pseudo-second order model represents better the kinetic experimental data. The results show that the Langmuir isotherm provides a slightly better fit to the experimental data compared with the Freundlich isotherm, indicating homogeneous distribution of active sites on carbon nanomaterials and monolayer adsorption. The separation factors RLare found in the range of 0–1, suggesting that the adsorption process is suitable for all adsorbents. The mechanisms for hexavalent chromium removal have been proposed as electrostatic interactions and hydrogen bonding.

关键词： Carbon nanotubes Graphene Adsorption Hexavalent chromium Kinetic

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Advantages of solitonic shape pulses for full-optical wireless communication links

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Chinese Optics Letters 2012年第4期10卷 1-3页

作者： José María Garrido Balsells Antonio Jurado-Navas Miguel Castillo-Vázquez ana Belén Moreno-Garrido Antonio Puerta-Notario Department of Communications Engineering University of Málaga Campus de Teatinos s/n E-29071 Málaga Spain

We propose the use of a power pulse shape of the widely known optical soliton, corresponding to the hyperbolic secant square function, for both conventional atmospheric optical communication systems and, especially, for new full-optical wireless communications. We analyze the performance of the proposed pulse in terms of peak-to-average optical power ratio （PAOPR） and bit error rate （BER）. During the analysis, we compare the proposed pulse shape against conventional rectangular and Gaussian pulse shapes with reduced duty cycle. Results show the noticeable superiority of the proposed pulse for atmospheric optical links.

关键词： Advantages of solitonic shape pulses for full-optical wireless communication links

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