Amélia Palma, and João Miguel Pereira, and Paula Soares

Aim of the study: In this work potential resin yield in a region of high forest ability where maritime pine is the main species was estimated in order to understand the viability of promoting resin exploitation. Area of study: This study was conducted in Castro Daire County in central region of Portugal. Material and methods: To quantify the resin yield of trees tapped for the first time two plots were installed in a maritime pine stand with average tree age 65 years. Before the beginning of t...

Stefan Liess, and Peter K. Snyder, and Arjun Kumar, and Vipin Kumar

A comparison of sea level pressure (SLP) trends in a subset of seven Coupled Model Intercomparison Project (CMIP) phase 5 general circulation models (GCM), namely decadal simulations with CCSM4, CanCM4, MPI-ESM-LR, FGOALS-g2, MIROC4h, MIROC5, and MRI-CGCM3, to their CMIP3 counterparts reveals an unrealistically strong forecast skill in CMIP3 models for trend predictions for 2001–2011 when using the 1979–2000 period to train the forecast. Boreal-winter SLP trends over five high-, mid-, and low-la...

Ahmed El Nemr, and Amany El-Sikaily, and Azza Khaled, and Ola Abdelwahab

Pterocladia capillacea, a red marine macroalgae, was tested for its ability to remove toxic hexavalent chromium from aqueous solution. A new activated carbon obtained from P. capillacea via acid dehydration was also investigated as an adsorbent for toxic chromium. The experiments were conducted to study the effect of important parameters such as pH, chromium concentration and adsorbent weight. Batch equilibrium tests at different pH conditions showed that at pH 1.0, a maximum chromium uptake was...

GISELE S. HECKLER, and MATEUS LOPES, and SABRINA M. SIMÕES, and ROBERTO M. SHIMIZU, and ROGERIO C. DA COSTA

We investigated the influence of environmental factors in spatial and temporal distribution of the seabob shrimp Xiphopenaeus kroyeri in Santos Bay and São Vicente Estuary, state of São Paulo, Brazil. Monthly samples were obtained, from May 2008 through April 2010, from four locations in the estuary and four in the bay. No individual was collected in the estuary and this was attributed to the low salinity means recorded in this environment. We collected 109,153 individuals in the bay and there w...

LR. Rörig, and JG. Tundisi, and CAF. Schettini, and J. Pereira-Filho, and JT. Menezes, and TCM. Almeida, and SR. Urban, and CM. Radetski, and RC. Sperb, and CA. Stramosk, and RS. Macedo, and MA. Castro-Silva, and JAA. Perez

The aim of this study was to understand how a stream ecosystem that flows from its fountainhead to its mouth inside a city, changes from a water resource to a point pollution source. A multidisciplinary descriptive approach was adopted, including the short-term temporal and spatial determination of physical, chemical, biological and ecotoxicological variables. Results showed that water quality rapidly decreases with increasing urbanization, leading the system to acquire raw sewage attributes eve...

Suburamaniyan Vijayakumar, and Andeson Amirthanathn

Objective: To identify the larvicidal activity of the seagrass extracts against Culex quinquefasciatus (Cx. quinquefasciatus) Methods: Seagrass extracts, Halodule pinifolia (H. pinifolia), Cymodocea serrulata (C. serrulata) and Thalasia testudinum (T. testudinum) were dissolved in dimethylsulfoxide to prepare a graded series of concentration. Batches of 25 early 4th instars larvae of Cx. quinquefasciatus were transferred to 250 mL enamel bowl containing 199 mL of distilled water and 1 mL of...

Şükran Çaklı, and Berna Kılınç

Pravat Kumar Shit, and Gouri Sankar Bhunia, and Ramkrishna Maiti

The present paper is based on field investigation and measurement of rill erosion processes at Rangamati Experimental Station (Medinipur, West Bengal in India). In rill experiments, three different natural rills were studies in field for understanding of the dynamics of soil erosion processes of a rill catchment area. Geometric and morphological characteristics of each rill catchment area were analyzed. Results showed the widening, deepening and extended of rills because of sidewall sloughing, k...

Luis Fernando Tavares de Menezes, and Francisco I. Pugnaire, and Gloria Matallana, and Felipe Cito Nettesheim, and Daniel Costa de Carvalho, and Eduardo Arcoverde de Mattos

ABSTRACT Germination rate and establishment success of plants in harsh environments depend on the ability of seeds to withstand unfavorable environmental conditions and avoid predators. Brazilian coastal plains, known as restinga, are subject to environmental factors that seriously limit plant establishment and survival (e.g. salinity, desiccation, oligotrophy, flooding, high temperature and radiation levels). We tested, both in field and laboratory experiments, conditions for germination and es...

J.-F. Lapierre, and P. A. del Giorgio

Despite the rapidly increasing volume of research on the biological and photochemical degradation of DOC (dissolved organic carbon) in aquatic environments, little is known of the large-scale patterns in biologically and photochemically degradable DOC (BDOC and PDOC, respectively) in continental watersheds, and on the links that exist between these two key properties that greatly influence the flow of carbon from continents to oceans. Here we explored the patterns in the concentrations and propo...

Sung-Ho Hong, and Seung-Hwan Ju

John A. Cunningham, and Alexandra Godinho, and Vladyslav Kushnir

Objectives: To determine whether Amazon's Mechanical Turk (MTurk) might be a viable means of recruiting participants for online intervention research. This was accomplished by conducting a randomized controlled trial of a previously validated intervention with participants recruited through MTurk. Methods: Participants were recruited to complete an online survey about their alcohol use through the MTurk platform. Those who met eligibility criterion for age and problem drinking were invited to co...

V Palastanga, and C. P. Slomp, and C. Heinze

Increased transfer of particulate matter from continental shelves to the open ocean during glacials may have had a major impact on the biogeochemistry of the ocean. Here, we assess the response of the coupled oceanic cycles of oxygen, carbon, phosphorus, and iron to the input of particulate organic carbon and reactive phosphorus from shelves. We use a biogeochemical ocean model and specifically focus on the Last Glacial Maximum (LGM). When compared to an interglacial reference run, our glacial s...

D. R. Corbett

For at least the past several decades, North Carolina's Neuse River Estuary (NRE) has been subject to water quality problems relating to increased eutrophication. Research initiated in the past several years have addressed the nutrient processes of the water column and the passive diffusion processes of the benthic sedimentary environment. Resuspension of bottom sediments, by bioturbation, tides, or winds, may also have a significant effect on the flux of nutrients in an estuarine system These p...

Paulo Ricardo Pezzuto, and Carlos Alberto Borzone

In Brazil, an industrial trawling fishery directed to Euvola ziczac started in 1973 and collapsed after 1980, when scallop landings reached 8,800 t. Since 1995 E. ziczac landings have not surpassed a few hundred kilograms. Based on surveys carried out in 1974-1975 and in 1995-1996, this work assesses temporal changes occurred in scallop distribution and relative abundance patterns and analyzes the current stock situation under the present management regimes applied to the local demersal trawling...

Namasivayam Manickam, and Nivetha Elumalai Selvamani, and Gopinath K. P.

Recently, the algae-for-fuel concept has gained renewed interest with energy prices fluctuating widely. Due to some restrictions over the oil extraction from algae, direct transesterification may be considered as a good alternative. In this study, to improve the performance of direct transesterification, ultrasound induction was carried out. A sonicator probe was used to induce the direct transesterification of Cladophora fracta, a freshwater macro alga, which contains 14% lipid on dry biomass b...

L. Velea, and G. L. Liberti, and A. M. Sempreviva, and C. Transerici

We propose the height <i>z_i</i> of the inversion in the vertical profile of potential temperature, on the top of a mixed layer or of a residual layer as a relevant parameter for retrieving information related to water vapour in the lower layers of the atmosphere, from currently available operational satellites information. We estimated <i>z_i</i> using an algorithm where a set of threshold values in the vertical gradients of potential temperature are used to analyse the avai...

DosSantos Marcos, and Martikainen Ilkka, and Nascimento Thiago, and Love Tiffany M, and Deboer Misty, and Maslowski Eric C, and Monteiro André, and Vincent Maurice, and Zubieta Jon-Kar, and DaSilva Alexandre F

<p>Abstract</p> <p>Background</p> <p>Although neuroimaging techniques have provided insights into the function of brain regions involved in Trigeminal Neuropathic Pain (TNP) in humans, there is little understanding of the molecular mechanisms affected during the course of this disorder. Understanding these processes is crucial to determine the systems involved in the development and persistence of TNP.</p> <p>Findings</p> <p>In this study, we examined the regional μ-opioid receptor (μOR) availab...

Lisiane Piazza, and Marice Regina Menta, and Cristiano Castoldi, and José Basileu Caon Reolão, and Rodrigo Schmidt, and Leonardo Calegari

O estudo visou avaliar a influência de um programa de exercícios aquáticos sobre a aptidão cardiorrespiratória e a pressão arterial em mulheres hipertensas. Dez hipertensas participaram do programa de exercícios aquáticos - aeróbicos, de fortalecimento, alongamento e relaxamento - duas vezes por semana durante 7 semanas, totalizando 14 sessões. Foram avaliadas pelo teste de esforço cardiorrespiratório antes e após o desenvolvimento do programa. A pressão arterial foi mensurada ao repouso e aos 1...

Montserrat C Rodríguez-Ruiz, and Miguel Andreu-Cazenave, and Catalina S Ruz, and Cristina Ruano-Chamorro, and Fabián Ramírez, and Catherine González, and Sergio A Carrasco, and Alejandro Pérez-Matus, and Miriam Fernández

The National Biodiversity Strategy developed in Chile aims to protect 10% of the surface area of the most relevant marine ecosystems. The waters around the Juan Fernández Archipelago were not protected until 2014, when a Multiple Use Marine Protected Area was created in the 12 nautical miles around the archipelago, which includes five marine parks in sites of high conservation value. Three of these parks are located around Robinson Crusoe Island. This study aims to define a baseline for monitori...

Mery Natali Silva Abreu, and Arminda Lucia Siqueira, and Waleska Teixeira Caiaffa

Os modelos de regressão logística ordinal vêm sendo aplicados com sucesso na análise de estudos epidemiológicos. Entretanto, a verificação da adequação de cada modelo tem recebido atenção limitada. O artigo apresenta uma breve análise dos principais modelos de regressão logística ordinal e as estratégias para ajuste s, as técnicas de verificação de qualidade do ajuste, bem como os comandos para execução nos softwares R e Stata. A metodologia é ilustrada com aplicação dos dados do Second National...

C. M. Huang, and C. M. Huang, and C. M. Huang, and C. M. Huang, and S. D. Zhang, and S. D. Zhang, and S. D. Zhang, and F. Yi, and F. Yi, and F. Yi

The characteristics of diurnal tide and planetary waves (PWs) in the troposphere and lower stratosphere (TLS) over Yichang (111&deg;18' E, 30&deg;42' N) were studied by using the data from intensive radiosonde observations in August 2006 (summer month) and January 2007 (winter month) on an eight-times-daily basis. The radiosonde observations of the diurnal tide and PWs in the TLS in the mid-latitudes have seldom been reported. We find that there exists dominant diurnal oscillations in the ...

Austin T. Humphries, and Megan K. La Peyre

Across the globe, discussions centered on the value of nature drive many conservation and restoration decisions. As a result, justification for management activities increasingly asks for two lines of evidence: (1) biological proof of augmented ecosystem function or service, and (2) monetary valuation of these services. For oyster reefs, which have seen significant global declines and increasing restoration work, the need to provide both biological and monetary evidence of reef services on a loc...

Télesphore eSIME - NGANDO

Since the discovery 2-3 decades ago that viruses of microbes are abundant in marine ecosystems, viral ecology has grown increasingly to reach the status of a full scientific discipline in environmental sciences. A dedicated ISVM society, the International Society for Viruses of Microorganisms (http://www.isvm.org/), was recently launched. Increasing studies in viral ecology are sources of novel knowledge related to the biodiversity of living things, the functioning of ecosystems, and the evoluti...

E. Jung, and E. Jung, and B. A. Albrecht, and A. Sorooshian, and A. Sorooshian, and P. Zuidema, and H. H. Jonsson

Precipitation tends to decrease as aerosol concentration increases in warm marine boundary layer clouds at fixed liquid water path (LWP). The quantitative nature of this relationship is captured using the precipitation susceptibility (<i>S</i>_<i>o</i>) metric. Previously published works disagree on the qualitative behavior of <i>S</i>_<i>o</i> in marine low clouds: <i>S</i>_<i>o</i> decreases monotonically with increasing LWP or cloud depth (<i>H</i>) in stra...

A. TERRÓN-SIGLERA, and D. LEÓN-MUEZ, and P. PEÑALVER-DUQUE, and F. ESPINOSA TORRE

The endangered and Mediterranean endemic orange coral (Astroides calycularis) hosts an important macrofaunal assemblage. The gut contents of the main peracarids associated with the orange coral were analysed. In total 161 specimens belonging to 11 species and 9 families were examined on the southern coast of the Iberian Peninsula. The gut content study was carried out introducing the specimens of each species in Hertwig’s liquid. The analysis revealed that the peracarid species associated with A...

Rony Kayrouz, and Blake F. Dear, and Eyal Karin, and Milena Gandy, and Vincent J. Fogliati, and Mathew D. Terides, and Nickolai Titov

This pilot study examined the efficacy and acceptability of a self-guided and culturally modified internet-delivered Cognitive Behaviour Therapy (iCBT) treatment for Arab people, aged 18 and over, with symptoms of depression and anxiety. Thirty-six participants from seven countries, with at least mild symptoms of depression (Patient Health Questionnaire 9-item; PHQ-9; total scores ≥5) or anxiety (Generalised Anxiety Disorder 7-item; GAD-7; total scores ≥5) accessed the online Arabic Wellbeing Co...

Tsung-Hsi Wang, and Shu-Fen Lin, and Kun-Yu Tsai, and Yu-Fu Liu

Objective: In Taiwan, the number of medical disputes and litigation has increased dramatically over the past 20 years. The seriousness of medical disputes continuing grows in clinical practice, especially in obstetricians. This study provided a possible solution to the medical dispute litigation issue. Materials and methods: The Ministry of Health and Welfare (MOHW) compensation program for birth incidents has been implemented since 2012 and it provided pecuniary compensation for mothers, newbor...

Jordi Landier, and Ladda Kajeechiwa, and May Myo Thwin, and Daniel M. Parker, and Victor Chaumeau, and Jacher Wiladphaingern, and Mallika Imwong, and Olivo Miotto, and Krittaya Patumrat, and Jureeporn Duanguppama, and Dominique Cerqueira, and Benoit Malleret, and Laurent Rénia, and Suphak Nosten, and Lorenz von Seidlein, and Clare Ling, and Stéphane Proux, and Vincent Corbel, and Julie A. Simpson, and Arjen M. Dondorp, and Nicholas J. White, and François H. Nosten

Background: Artemisinin and partner drug-resistant falciparum malaria is expanding over the Greater Mekong Sub-region (GMS). Eliminating falciparum malaria in the GMS while drugs still retain enough efficacy could prevent global spread of antimalarial resistance. Eliminating malaria rapidly requires targeting the reservoir of asymptomatic parasite carriers. This pilot trial aimed to evaluate the acceptability, safety, feasibility and effectiveness of mass-drug administration (MDA) in reducing ma...

Rony Kayrouz, and Blake F. Dear, and Eyal Karin, and Vincent J. Fogliati, and Nickolai Titov

The present pilot study examined the efficacy and acceptability of an internet-delivered Cognitive Behaviour Therapy (iCBT) intervention delivered in both English and Arabic languages to Arab Australians, aged 18 and over, with symptoms of depression and anxiety. Thirteen participants with at least mild symptoms of depression on the (Patient Health Questionnaire 9-item; PHQ-9; total scores ≥5) or anxiety (Generalised Anxiety Disorder 7-item; GAD-7; total scores ≥5) accessed the online Arabic Wel...

Shaojuan Ma, and Duan Dong

The asymptotic stability of a discrete logistic model with random growth coefficient is studied in this paper. Firstly, the discrete logistic model with random growth coefficient is built and reduced into its deterministic equivalent system by orthogonal polynomial approximation. Then, the linear stability theory and the Jury criterion of nonlinear deterministic discrete systems are applied to the equivalent one. At last, by mathematical analysis, we find that the parameter interval for asymptot...

Bruno Guinand, and Nolwenn Quéré, and Frédérique Cerqueira, and Erick Desmarais, and François Bonhomme

The existence of cryptic salinity-related phenotypes has been hypothesized in the “euryhaline” sea bass (Dicentrarchus labrax). How differential osmoregulation costs between freshwater and saltwater environments affect fitness and phenotypic variation is misunderstood in this species. During an experiment lasting around five months, we investigated changes in the whole body mass and in the expression of growth-related genes (insulin-like growth factor 1 [IGF-1]; growth hormone receptor [GHR]) in...

Hugo Arancibia, and Sergio Neira

We explore long-term changes in the mean trophic level (TLm) of Central Chile fishery landings, using a 21 years data series (1979-1999) of official landings (Chilean Fisheries Service) of 16 species that comprise about 95% of total landing, and their corresponding trophic level estimated using gut content analysis and a trophic model of the Central Chile marine ecosystem. Because total landings off Central Chile have been strongly influenced by landings of horse mackerel (Trachurus symmetricus)...

Beuy Joob, and Viroj Wiwanitkit

No

Thaís Bento Lima-Silva, and Aline Teixeira Fabrício, and Laís dos Santos Vinholi e Silva, and Glaúcia Martins de Oliveira, and Wesley Turci da Silva, and Priscilla Tiemi Kissaki, and Anna Pereira Fernandes da Silva, and Tamiris Fessel Sasahara, and Tiago Nascimento Ordonez, and Thalita Bianchi de Oliveira, and Flávia Ogava Aramaki, and Adriana Buriti, and Mônica Sanches Yassuda

ABSTRACT Executive functions (EF) refer to the cognitive skills necessary to formulate a goal, plan, execute plans effectively, and to perform self-monitoring and self-correction. Several aspects of EF change during the normal aging process. Objectives: To train skills associated with executive functions in the elderly and to detect possible impact on objective EF tests and self-reports of functional status. Methods: A cross-sectional study involving an intervention and pre and post testing ...

Luminosu Ioan V.

The "Politehnica" University of Timisoara has built a thermo solar system implemented on the ground floor and first floor of a building. The system is made up of solar water collectors, an air-water heat exchanger, a bedrock heat accumulator and a minimal thermal loss enclosure. The statistical processing of the measurements performed during spring and autumn 2000 resulted in determining the average features of the system and in the evaluation of its efficiency in maintaining the enclosure's tem...

Pushparaj Sujith, and Baskaran Rohini, and Singaram Jayalakshmi

Objective: To purify and partially characterize the antimicrobial compounds from bacteria Bacillus sp., isolated from fish gut. Methods: Protein and fatty acids were isolated from the bacteria and checked for the presence of antibacterial activity. Protein has been purified to apparent homogeneity from the supernatants of culture by means of ammonium sulphate precipitation followed by dialysis. Fourier transform infrared spectroscopy analyses were performed for proteins to identify the func...

Robin Sharma, and Samiksha Gupta, and Dinesh P Asati, and T Karuna, and Shashank Purwar, and Debasis Biswas

Context: The conventional diagnostic tools for dermatophytoses suffer from several limitations including low sensitivity, specificity, and long turn-around-time. Aims: The present study was, therefore, performed to evaluate the performance of a polymerase chain reaction (PCR)-based method for the diagnosis of this condition. Settings and Design: The study was conducted in the Dermatology outpatient department of a tertiary care teaching hospital in central India over a period of 3 months from Ju...

Goswami N, and Kavcic V, and Marusic U, and Simunic B, and R&ouml;ssler A, and Hinghofer-Szalkay H, and Pisot R

Nandu Goswami,1 Voyko Kavcic,2 Uros Marusic,3 Bostjan Simunic,3 Andreas R&ouml;ssler,1 Helmut Hinghofer-Szalkay,1 Rado Pisot3 1Institute of Physiology, Medical University of Graz, Graz, Austria; 2Institute of Gerontology, Wayne State University, Detroit, MI, USA; 3Institute for Kinesiology Research, University of Primorska, Ankaran, Slovenia Abstract: We investigated the effects of bed rest (BR) immobilization, with and without computerized cognitive training with virtual spatial navigation ta...

Raymond T. Dizon, and Helen T. Yap

The present century is witness to unprecedented levels of coral reef degradation worldwide. Current understanding based on traditional ideas is unlikely to capture adequately the dynamics of phenomena accompanying this trend. In this regard, the ideas of complexity are reviewed. Some applications to coral reefs as complex systems have already been discussed in the literature although further progress is warranted as the search for new and more effective management tools continues, and the direct...

Eva Schemmel, and Alan M. Friedlander, and Pelika Andrade, and Kuʻulei Keakealani, and Linda M. Castro, and Chad Wiggins, and Bart A. Wilcox, and Yumi Yasutake, and John N. Kittinger

Small-scale fisheries across the globe provide critical food security, livelihoods, and human well-being, but are threatened by a combination of local and global stressors, including overexploitation, pollution, and climate change. Participatory approaches to management, especially those that incorporate local communities and customary knowledge can provide meaningful biological information that supports sustainable fisheries management and builds local adaptive capacity to changing ocean condit...

Marwa G. Hennawy, and Noha M. Elhosseiny, and Hussein Sultan, and Wael Abdelfattah, and Yousry Akl, and Nirmeen A. Sabry, and Ahmed S. Attia

Chronic obstructive pulmonary disease (COPD) is caused by α1-antitrypsin deficiency (AATD) genetic susceptibility and exacerbated by infection. The current pilot study aimed at studying the combined effect of AATD and bacterial loads on the efficacy of COPD conventional pharmacotherapy. Fifty-nine subjects (29 controls and 30 COPD patients) were tested for genetic AATD and respiratory function. The bacterial loads were determined to the patients’ group who were then given a long acting beta-agon...

Nadisa Theresia Putri, and Dedi Jusadi, and Mia Setiawati, and Mas Tri Djoko Sunarno

<p class="NoParagraphStyle"><strong>ABSTRACT</strong></p><p class="NoParagraphStyle"><em> </em></p><p class="NoParagraphStyle">The high composition of import raw material of fish diet in Indonesia causes feed price expensively and should be replaced using local materials such as green macro algae. It is, therefore, this study aimed to evaluate effect of diet containing the <em>Caulerpa lentillifera</em>, as feed ingredient in the diet of Nile tilapia <em>Oreochromis niloticus</em>. This study co...

Patrick D. Shirey, and Michael A. Brueseke, and Jillian B. Kenny, and Gary A. Lamberti

At a global scale, aquatic ecosystems are being altered by human activities at a greater rate than at any other time in history. In recent years, grassroots efforts have generated interest in the restoration of degraded or destroyed aquatic habitats, especially small wetlands and streams where such projects are feasible with local resources. We present ecological management lessons learned from 17 years of monitoring the fish community response to the channel relocation and reach-level restorati...

Kirsten eEberle, and Theresa eWaters, and Eric eJensen, and Stephanie eVenn-Watson, and Randy E Sacco

Chronic inflammation has been associated with insulin resistance and type 2 diabetes (T2D) in humans. Postmortem hepatic and splenic tissue from a 46-year-old geriatric male bottlenose dolphin (Tursiops truncatus) with insulin resistance (chronic hyperinsulinemia with hyperglycemia), chronic inflammation (white blood cell count greater than 12,000 cells/μL), and mild fatty liver disease was evaluated for elevated pro-inflammatory mediators. Cytokine mRNA expression in postmortem hepatic and sp...

Ioannis D. Laoutaris, and Athanasios Dritsas, and Panayotis Kariofyllis

Nuno Vasco-Rodrigues, and Nuno Vasco-Rodrigues, and Nuno Vasco-Rodrigues

The boundaries for geographic distributions of species are being redesigned continuously, as referred by several authors. In recent years, tropical and sub-tropical fish species have been registered for the first time in the coast of Portugal. Climate change may be one of the main reasons for this, driving these species to migrate to places where previously the climate wasn’t warm enough for them. Another possible explanation for this lack of knowledge on the true geographic distribution range ...

Arianna Manciocco, and Paolo Coluccio, and Annamaria Passantino

The use of fish for experimental purposes has seen a significant increase over the past years, consequently scientific findings on factors influencing welfare of these vertebrates are now available, as well as debates on their capacity of experiencing suffering are increasingly found in animal welfare discussions. Nowadays, in Europe, the use of these animals as experimental models is regulated by the Recommendation 2007/526/EC, where in the Section on the species-specific guidelines for fish, a...

Alsuwaida Abdulkareem, and Farag Youssef, and Al Sayyari Abdulla, and Mousa Dujanah, and Alhejaili Fayez, and Al-Harbi Ali, and Housawi Abdulrahman, and Mittal Bharati, and Singh Ajay

There are no available data about the prevalence of chronic kidney disease (CKD) and its risk factors in the general population of the kingdom of Saudi Arabia. To estimate the prevalence of CKD and its associated risk factors in the Saudi population, we conducted a pilot community-based screening program in commercial centers in Riyadh, Saudi Arabia. Candidates were interviewed and blood and urine samples were collected. Participants were categorized to their CKD stage according to their estimat...

Ling Bai, and Ke Wang

We study a time-dependent logistic equation with periodic coefficients. First, we show that the impulsive harvest population equation has impulsive periodic solutions for constant effort harvest and for proportional harvest. Second, we investigate the optimal harvest effort that maximizes the sustainable yield per unit of time. Then we determine the corresponding optimal population levels. Our results generalize the results presented in [10].