The African Field Epidemiology Network-Networking for effective field epidemiology capacity building and service delivery

Science.gov (United States)

Gitta, Sheba Nakacubo; Mukanga, David; Babirye, Rebecca; Dahlke, Melissa; Tshimanga, Mufuta; Nsubuga, Peter

2011-01-01

Networks are a catalyst for promoting common goals and objectives of their membership. Public Health networks in Africa are crucial, because of the severe resource limitations that nations face in dealing with priority public health problems. For a long time, networks have existed on the continent and globally, but many of these are disease-specific with a narrow scope. The African Field Epidemiology Network (AFENET) is a public health network established in 2005 as a non-profit networking alliance of Field Epidemiology and Laboratory Training Programs (FELTPs) and Field Epidemiology Training Programs (FETPs) in Africa. AFENET is dedicated to helping ministries of health in Africa build strong, effective and sustainable programs and capacity to improve public health systems by partnering with global public health experts. The Network's goal is to strengthen field epidemiology and public health laboratory capacity to contribute effectively to addressing epidemics and other major public health problems in Africa. AFENET currently networks 12 FELTPs and FETPs in sub-Saharan Africa with operations in 20 countries. AFENET has a unique tripartite working relationship with government technocrats from human health and animal sectors, academicians from partner universities, and development partners, presenting the Network with a distinct vantage point. Through the Network, African nations are making strides in strengthening their health systems. Members are able to: leverage resources to support field epidemiology and public health laboratory training and service delivery notably in the area of outbreak investigation and response as well as disease surveillance; by-pass government bureaucracies that often hinder and frustrate development partners; and consolidate efforts of different partners channelled through the FELTPs by networking graduates through alumni associations and calling on them to offer technical support in various public health capacities as the need arises

Vectorial analysis of the collimated beam of a small Gaussian source

Science.gov (United States)

Cao, Changqing; Wang, Ting; Zeng, Xiaodong; Feng, Zhejun; Zhang, Wenrui; Zhang, Xiaobing; Chen, Kun

2018-03-01

A vectorial analysis method to describe the collimated beam is proposed, the formulas of the intensity distribution and divergence angles represented in terms of Bessel functions are derived, and the propagation properties such as the vectorial structure of the collimated field and the shape of the beam spot are discussed in detail. Omitting the vectorial nature of the collimated beam can cause an error of 7.6% in determining the intensity distribution on the optical axis of the collimated beam.

Diatomic Metasurface for Vectorial Holography.

Science.gov (United States)

Deng, Zi-Lan; Deng, Junhong; Zhuang, Xin; Wang, Shuai; Li, Kingfai; Wang, Yao; Chi, Yihui; Ye, Xuan; Xu, Jian; Wang, Guo Ping; Zhao, Rongkuo; Wang, Xiaolei; Cao, Yaoyu; Cheng, Xing; Li, Guixin; Li, Xiangping

2018-05-09

The emerging metasurfaces with the exceptional capability of manipulating an arbitrary wavefront have revived the holography with unprecedented prospects. However, most of the reported metaholograms suffer from limited polarization controls for a restrained bandwidth in addition to their complicated meta-atom designs with spatially variant dimensions. Here, we demonstrate a new concept of vectorial holography based on diatomic metasurfaces consisting of metamolecules formed by two orthogonal meta-atoms. On the basis of a simply linear relationship between phase and polarization modulations with displacements and orientations of identical meta-atoms, active diffraction of multiple polarization states and reconstruction of holographic images are simultaneously achieved, which is robust against both incident angles and wavelengths. Leveraging this appealing feature, broadband vectorial holographic images with spatially varying polarization states and dual-way polarization switching functionalities have been demonstrated, suggesting a new route to achromatic diffractive elements, polarization optics, and ultrasecure anticounterfeiting.

Vectorial and plane energy fluences - useful concepts in radiation physics

International Nuclear Information System (INIS)

Carlsson, C.A.

1977-06-01

The vectorial physical quantities describing the radiation field are defined in this report. The use of these quantities is rare in the radiation dosimetry literature since a knowledge of the directions of motion of the ionizing particle is often uninteresting when determining absorbed doses. However the plane energy fluence rate is a useful quantity in cases with plane irradiation geometries. The plane energy fluence rate is closely related to the vectorial energy fluence rate. The backscattering properties of a medium can be expressed in terms either of its albedo or its reflection-coefficient (backscatter-coefficient). These quantities are discussed in order to derive useful relations between the plane energy fluence and the energy fluence at points on an extended plane surface. Examples are also given of erroneous use of energy fluence instead of vectorial or plane energy fluence. The examples are taken from roentgen diagnostic examinations. To prevent further mistakes it could be valuable if the quantities of vectorial and plane fluences were introduced in text books in radiation dosimetry. Awaiting for this, this report may hopefully be useful. (E.R.)

Data-based mathematical modeling of vectorial transport across double-transfected polarized cells.

Science.gov (United States)

Bartholomé, Kilian; Rius, Maria; Letschert, Katrin; Keller, Daniela; Timmer, Jens; Keppler, Dietrich

2007-09-01

Vectorial transport of endogenous small molecules, toxins, and drugs across polarized epithelial cells contributes to their half-life in the organism and to detoxification. To study vectorial transport in a quantitative manner, an in vitro model was used that includes polarized MDCKII cells stably expressing the recombinant human uptake transporter OATP1B3 in their basolateral membrane and the recombinant ATP-driven efflux pump ABCC2 in their apical membrane. These double-transfected cells enabled mathematical modeling of the vectorial transport of the anionic prototype substance bromosulfophthalein (BSP) that has frequently been used to examine hepatobiliary transport. Time-dependent analyses of (3)H-labeled BSP in the basolateral, intracellular, and apical compartments of cells cultured on filter membranes and efflux experiments in cells preloaded with BSP were performed. A mathematical model was fitted to the experimental data. Data-based modeling was optimized by including endogenous transport processes in addition to the recombinant transport proteins. The predominant contributions to the overall vectorial transport of BSP were mediated by OATP1B3 (44%) and ABCC2 (28%). Model comparison predicted a previously unrecognized endogenous basolateral efflux process as a negative contribution to total vectorial transport, amounting to 19%, which is in line with the detection of the basolateral efflux pump Abcc4 in MDCKII cells. Rate-determining steps in the vectorial transport were identified by calculating control coefficients. Data-based mathematical modeling of vectorial transport of BSP as a model substance resulted in a quantitative description of this process and its components. The same systems biology approach may be applied to other cellular systems and to different substances.

Vectorial optical fields fundamentals and applications

CERN Document Server

2014-01-01

Polarization is a vector nature of light that plays an important role in optical science and engineering. While existing textbook treatments of light assume beams with spatially homogeneous polarization, there is an increasing interest in vectorial optical fields with spatially engineered states of polarization. New effects and phenomena have been predicted and observed for light beams with these unconventional polarization states. This edited review volume aims to provide a comprehensive overview and summarize the latest developments in this important emerging field of optics. This book will cover the fundamentals including mathematical and physical descriptions, experimental generation, manipulation, focusing, propagation, and the applications of the engineered vectorial optical fields in focal field engineering, plasmonic focusing and optical antenna, single molecular imaging, optical tweezers/trapping, as well as optical measurements and instrumentations. Readership: Students, professionals, post-graduat...

An Assessment of Epidemiology Capacity in a One Health Team at the Provincial Level in Thailand

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Soawapak Hinjoy

2016-10-01

Full Text Available A multi-sectoral core epidemiology capacity assessment was conducted in provinces that implemented One Health services in order to assess the efficacy of a One Health approach in Thailand. In order to conduct the assessment, four provinces were randomly selected as a study group from a total of 19 Thai provinces that are currently using a One Health approach. As a control group, four additional provinces that never implemented a One Health approach were also sampled. The provincial officers were interviewed on the epidemiologic capacity of their respective provinces. The average score of epidemiologic capacity in the provinces implementing the One Health approach was 66.45%, while the provinces that did not implement this approach earned a score of 54.61%. The epidemiologic capacity of surveillance systems in provinces that utilized the One Health approach earned higher scores in comparison to provinces that did not implement the approach (75.00% vs. 53.13%, p-value 0.13. Although none of the capacity evaluations showed significant differences between the two groups, we found evidence that provinces implementing the One Health approach gained higher scores in both surveillance and outbreak investigation capacities. This may be explained by more efficient capacity when using a One Health approach, specifically in preventing, protecting, and responding to threats in local communities.

Coherence for vectorial waves and majorization

OpenAIRE

Luis, Alfredo

2016-01-01

We show that majorization provides a powerful approach to the coherence conveyed by partially polarized transversal electromagnetic waves. Here we present the formalism, provide some examples and compare with standard measures of polarization and coherence of vectorial waves.

Multiplexed optical data storage and vectorial ray tracing

Directory of Open Access Journals (Sweden)

Foreman M.R.

2010-06-01

Full Text Available With the motivation of creating a terabyte-sized optical disk, a novel imaging technique is implemented. This technique merges two existing technologies: confocal microscopy and Mueller matrix imaging. Mueller matrix images from a high numerical space are obtained. The acquisition of these images makes the exploration of polarisation properties in a sample possible. The particular case of optical data storage is used as an example in this presentation. Since we encode information into asymmetric datapits (see Figure 1, the study of the polarisation of the scattered light can then be used to recover the orientation of the pit. It is thus possible to multiplex information by changing the angle of the mark. The storage capacity in the system is hence limited by the number of distinct angles that the optical system can resolve. This presentation thus answers the question; what is the current storage capacity of a polarisation sensitive optical disk? After a brief introduction to polarisation, the decoding method and experimental results are presented so as to provide an answer to this question. With the aim of understanding high NA focusing, an introduction to vectorial ray tracing is then given.

Three-dimensional vectorial multifocal arrays created by pseudo-period encoding

Science.gov (United States)

Zeng, Tingting; Chang, Chenliang; Chen, Zhaozhong; Wang, Hui-Tian; Ding, Jianping

2018-06-01

Multifocal arrays have been attracting considerable attention recently owing to their potential applications in parallel optical tweezers, parallel single-molecule orientation determination, parallel recording and multifocal multiphoton microscopy. However, the generation of vectorial multifocal arrays with a tailorable structure and polarization state remains a great challenge, and reports on multifocal arrays have hitherto been restricted either to scalar focal spots without polarization versatility or to regular arrays with fixed spacing. In this work, we propose a specific pseudo-period encoding technique to create three-dimensional (3D) vectorial multifocal arrays with the ability to manipulate the position, polarization state and intensity of each focal spot. We experimentally validated the flexibility of our approach in the generation of 3D vectorial multiple spots with polarization multiplicity and position tunability.

Distribution of sibling species of Anopheles culicifacies s.l. and Anopheles fluviatilis s.l. and their vectorial capacity in eight different malaria endemic districts of Orissa, India

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Asima Tripathy

2010-12-01

Full Text Available The study was undertaken in eight endemic districts of Orissa, India, to find the members of the species complexes of Anopheles culicifacies and Anopheles fluviatilis and their distribution patterns. The study area included six forested districts (Keonjhar, Angul, Dhenkanal, Ganjam, Nayagarh and Khurda and two non-forested coastal districts (Puri and Jagatsingpur studied over a period of two years (June 2007-May 2009. An. culicifacies A, B, C and D and An. fluviatilis S and T sibling species were reported. The prevalence of An. culicifacies A ranged from 4.2-8.41%, B from 54.96-76.92%, C from 23.08-33.62% and D from 1.85-5.94% (D was reported for the first time in Orissa, except for occurrences in the Khurda and Nayagarh districts. The anthropophilic indices (AI were 3.2-4.8%, 0.5-1.7%, 0.7-1.37% and 0.91-1.35% for A, B, C and D, respectively, whereas the sporozoite rates (SR were 0.49-0.54%, 0%, 0.28-0.37% and 0.41-0.46% for A, B, C and D, respectively. An. fluviatilis showed a similarly varied distribution pattern in which S was predominant (84.3% overall; its AI and SR values ranged from 60.7-90.4% and 1.2-2.32%, respectively. The study observed that the co-existence of potential vector sibling species of An. culicifacies (A, C and D and An. fluviatilis S (> 50% was responsible for the high endemicity of malaria in forested districts such as Dhenkanal, Keonjhar, Angul, Ganjam, Nayagarh and Khurda (> 5% slide positivity rate. Thus, the epidemiological scenario for malaria is dependent on the distribution of the vector sibling species and their vectorial capacity.

Distribution of sibling species of Anopheles culicifacies s.l. and Anopheles fluviatilis s.l. and their vectorial capacity in eight different malaria endemic districts of Orissa, India.

Science.gov (United States)

Tripathy, Asima; Samanta, Luna; Das, Sachidananda; Parida, Sarat Kumar; Marai, Nitisheel; Hazra, Rupenansu Kumar; Kar, Santanu Kumar; Mahapatra, Namita

2010-12-01

The study was undertaken in eight endemic districts of Orissa, India, to find the members of the species complexes of Anopheles culicifacies and Anopheles fluviatilis and their distribution patterns. The study area included six forested districts (Keonjhar, Angul, Dhenkanal, Ganjam, Nayagarh and Khurda) and two non-forested coastal districts (Puri and Jagatsingpur) studied over a period of two years (June 2007-May 2009). An. culicifacies A, B, C and D and An. fluviatilis S and T sibling species were reported. The prevalence of An. culicifacies A ranged from 4.2-8.41%, B from 54.96-76.92%, C from 23.08-33.62% and D from 1.85-5.94% (D was reported for the first time in Orissa, except for occurrences in the Khurda and Nayagarh districts). The anthropophilic indices (AI) were 3.2-4.8%, 0.5-1.7%, 0.7-1.37% and 0.91-1.35% for A, B, C and D, respectively, whereas the sporozoite rates (SR) were 0.49-0.54%, 0%, 0.28-0.37% and 0.41-0.46% for A, B, C and D, respectively. An. fluviatilis showed a similarly varied distribution pattern in which S was predominant (84.3% overall); its AI and SR values ranged from 60.7-90.4% and 1.2-2.32%, respectively. The study observed that the co-existence of potential vector sibling species of An. culicifacies (A, C and D) and An. fluviatilis S (> 50%) was responsible for the high endemicity of malaria in forested districts such as Dhenkanal, Keonjhar, Angul, Ganjam, Nayagarh and Khurda (> 5% slide positivity rate). Thus, the epidemiological scenario for malaria is dependent on the distribution of the vector sibling species and their vectorial capacity.

Determination of Age and Vectorial Capacity of Anopheles Maculipennis Sensu Lato in the Central Plateau of Iran

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Hamideh Edalat

2016-06-01

Full Text Available Background and Purpose: Islamic Republic of Iran has greatly reduced its malaria burden and has a national goal to eliminate malaria by 2025. The aim of this study was to determine the population dynamics of Anopheles maculipennis sensu lato, in relation to probable malaria transmission. For this purpose, the study was conducted in three villages in Isfahan Province of Iran, from April to March 2014. Materials and Methods: Two mosquitoes sampling methods were conducted, comprises human landing catch and human bed net collection. The results of this investigation were subjected to one-way ANOVA using SPSS. Results: A. maculipennis s.l. was found as a dominant vector with exophagic and endophilic behavior. Two peaks of blood feeding were observed, 9.00-10.00 p.m and 1.00-2.00 a.m. The gonotrophic cycle, survival rate, and life expectancy of the species were 4, 0.82, and 5 days, respectively. Malaria vectorial capacity of A. maculipennis was measured 0.0128 and 0.059 for Plasmodium vivax and Plasmodium Falciparum, respectively. Conclusion: The findings indicate that there is a negative correlation between the temperature and daily age of A. maculipennis s.l. The method described can be used as a standard method to determine the daily age of Anopheles, as well as of other mosquito species since it is fast and precise and needs small samples. Survey on the age structure of vectors is very important as it is useful in monitoring the success of large-scale vector control measures.

Effect of Feeding Blood Treated with Isometamidium Chloride to Glossina Morsitans Morsitans on the Flies' Subsequent Vectorial Capacity, and Evaluation of an In Vitro Feeding System for the Maintenance of Infected Tsetse Flies

Energy Technology Data Exchange (ETDEWEB)

Van den Bossche, P; Van Den Abbeele, J; De Deken, R [Veterinary and Parasitology Departments, Prince Leopold Institute of Tropical Medicine, Nationalestraat 155, 2000 Antwerp (Belgium)

2012-07-15

A repercussion of the release of large numbers of sterile male tsetse flies is the sudden increase in the number of disease vectors. To avoid the potential creation of a trypanosomosis epidemic, studies were conducted aimed at reducing the vectorial capacity of male tsetse flies by offering them a single bloodmeal containing the prophylactic trypanocidal drug isometamidium chloride. Experiments using the pair G. m. morsitans and T. congolense or T. b. brucei showed that a single treatment with isometamidium chloride protected flies from infection with susceptible and resistant trypanosomes for up to 5 days post-treatment. Starvation of isometamidium-treated flies increased their susceptibility to infection with T. congolense. Studies evaluating in vitro feeding of infected flies on citrated bovine blood showed that this feeding regime adversely affected the capacity of trypanosomes to develop in the fly. (author)

Vector competence: Entomological considerations and its implications on the epidemiology of Dengue Competencia vectorial: consideraciones entomológicas y su influencia sobre la epidemiología del Dengue

Directory of Open Access Journals (Sweden)

Jorge Emilio Osorio Benítez

2010-05-01

Full Text Available

Vector-borne diseases are a serious problem in public health, especially in tropical and subtropical areas where environmental conditions favor the survival and expansion of vectors into new habitats.

Dengue fever is one of the most important vector-borne diseases transmitted by arthropods (arbovirosis worldwide. The etiologic agent of the disease is the dengue virus, which is transmitted by the bite of bloodsucking Aedes aegypti mosquitoes. The virus-vector interaction is essential for the efficient transmission of the disease, and depends on both, viral factors and vector competence or intrinsic vector capacity to be infected with the virus. Vector competence allows virus replication and subsequent transmission to susceptible hosts. Factors that influence vector capacity include: natural barriers to infection, immunological defenses as well as the presence of receptors for the virus. All these factors in addition to the viral characteristics will determine the degree of transmission. There is a need for a better understanding of the virus-vector relationship and its epidemiological implications. These issues are addressed in this article.

Las enfermedades transmitidas por vectores constituyen un complejo problema de salud en el ámbito mundial, especialmente en áreas tropicales y

Nociones de geometría vectorial

OpenAIRE

Ospina Arteaga, Omar Evelio

1990-01-01

Las presentes notas de geometría vectorial pretenden ser una ayuda para los estudiantes que se inician en el tema de vectores y deberá ser complementado con ejercicios sobre el tema. Este texto contiene temas de interés tales como: Espacios euclidianos, Distancian entre dos puntos, Concepto de vector, Igualdad de vectores, entre otros relacionados con el estudio de vectores.

Epidemiological and ecological determinants of Zika virus transmission in an urban setting.

Science.gov (United States)

Lourenço, José; Maia de Lima, Maricelia; Faria, Nuno Rodrigues; Walker, Andrew; Kraemer, Moritz Ug; Villabona-Arenas, Christian Julian; Lambert, Ben; Marques de Cerqueira, Erenilde; Pybus, Oliver G; Alcantara, Luiz Cj; Recker, Mario

2017-09-09

The Zika virus has emerged as a global public health concern. Its rapid geographic expansion is attributed to the success of Aedes mosquito vectors, but local epidemiological drivers are still poorly understood. Feira de Santana played a pivotal role in the Chikungunya epidemic in Brazil and was one of the first urban centres to report Zika infections. Using a climate-driven transmission model and notified Zika case data, we show that a low observation rate and high vectorial capacity translated into a significant attack rate during the 2015 outbreak, with a subsequent decline in 2016 and fade-out in 2017 due to herd-immunity. We find a potential Zika-related, low risk for microcephaly per pregnancy, but with significant public health impact given high attack rates. The balance between the loss of herd-immunity and viral re-importation will dictate future transmission potential of Zika in this urban setting.

Far-field divergence of a vectorial plane wave diffracted by a circular aperture from the vectorial structure

International Nuclear Information System (INIS)

Zhou Guo-Quan

2011-01-01

Based on the vectorial structure of an electromagnetic wave, the analytical and concise expressions for the TE and TM terms of a vectorial plane wave diffracted by a circular aperture are derived in the far-field. The expressions of the energy flux distributions of the TE term, the TM term and the diffracted plane wave are also presented. The ratios of the power of the TE and TM terms to that of the diffracted plane wave are examined in the far-field. In addition, the far-field divergence angles of the TE term, the TM term and the diffracted plane wave, which are related to the energy flux distribution, are investigated. The different energy flux distributions of the TE and TM terms result in the discrepancy of their divergence angles. The influences of the linearly polarized angle and the radius of the circular aperture on the far-field divergence angles of the TE term, the TM term and the diffracted plane wave are discussed in detail. This research may promote the recognition of the optical propagation through a circular aperture. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

Vectorial Ekeland Variational Principles and Inclusion Problems in Cone Quasi-Uniform Spaces

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Jiang Zhu

2012-01-01

principle, vectorial quasiequilibrium principle are obtained. Also, several other important principles in nonlinear analysis are extended to cone quasi-uniform spaces. The results of this paper extend, generalize, and improve the corresponding results for Ekeland's variational principles of the directed vectorial perturbation type and other generalizations of Ekeland's variational principles in the setting of F-type topological space and quasi-metric spaces in the literatures. Even in usual real metric spaces, some of our results are new.

Determination of the polarization states of an arbitrary polarized terahertz beam: vectorial vortex analysis.

Science.gov (United States)

Wakayama, Toshitaka; Higashiguchi, Takeshi; Oikawa, Hiroki; Sakaue, Kazuyuki; Washio, Masakazu; Yonemura, Motoki; Yoshizawa, Toru; Tyo, J Scott; Otani, Yukitoshi

2015-03-24

Vectorial vortex analysis is used to determine the polarization states of an arbitrarily polarized terahertz (0.1-1.6 THz) beam using THz achromatic axially symmetric wave (TAS) plates, which have a phase retardance of Δ = 163° and are made of polytetrafluorethylene. Polarized THz beams are converted into THz vectorial vortex beams with no spatial or wavelength dispersion, and the unknown polarization states of the incident THz beams are reconstructed. The polarization determination is also demonstrated at frequencies of 0.16 and 0.36 THz. The results obtained by solving the inverse source problem agree with the values used in the experiments. This vectorial vortex analysis enables a determination of the polarization states of the incident THz beam from the THz image. The polarization states of the beams are estimated after they pass through the TAS plates. The results validate this new approach to polarization detection for intense THz sources. It could find application in such cutting edge areas of physics as nonlinear THz photonics and plasmon excitation, because TAS plates not only instantaneously elucidate the polarization of an enclosed THz beam but can also passively control THz vectorial vortex beams.

Vectorial Resilient PC(l) of Order k Boolean Functions from AG-Codes

Institute of Scientific and Technical Information of China (English)

Hao CHEN; Liang MA; Jianhua LI

2011-01-01

Propagation criteria and resiliency of vectorial Boolean functions are important for cryptographic purpose (see [1- 4, 7, 8, 10, 11, 16]). Kurosawa, Stoh [8] and Carlet [1]gave a construction of Boolean functions satisfying PC(l) of order k from binary linear or nonlinear codes. In this paper, the algebraic-geometric codes over GF(2m) are used to modify the Carlet and Kurosawa-Satoh's construction for giving vectorial resilient Boolean functions satisfying PC(l) of order k criterion. This new construction is compared with previously known results.

Vectorial diffraction properties of THz vortex Bessel beams.

Science.gov (United States)

Wu, Zhen; Wang, Xinke; Sun, Wenfeng; Feng, Shengfei; Han, Peng; Ye, Jiasheng; Yu, Yue; Zhang, Yan

2018-01-22

A vortex Bessel beam combines the merits of an optical vortex and a Bessel beam, including a spiral wave front and a non-diffractive feature, which has immense application potentials in optical trapping, optical fabrication, optical communications, and so on. Here, linearly and circularly polarized vortex Bessel beams in the terahertz (THz) frequency range are generated by utilizing a THz quarter wave plate, a spiral phase plate, and Teflon axicons with different opening angles. Taking advantage of a THz focal-plane imaging system, vectorial diffraction properties of the THz vortex Bessel beams are comprehensively characterized and discussed, including the transverse (Ex, Ey) and longitudinal (Ez) polarization components. The experimental phenomena are accurately simulated by adopting the vectorial Rayleigh diffraction integral. By varying the opening angle of the axicon, the characteristic parameters of these THz vortex Bessel beams are exhibited and compared, including the light spot size, the diffraction-free range, and the phase evolution process. This work provides the precise experimental and theoretical bases for the comprehension and application of a THz vortex Bessel beam.

The generalized vectorial laws of reflection and refraction

International Nuclear Information System (INIS)

Bhattacharjee, Pramode Ranjan

2005-01-01

This paper discloses two important discoveries. These are: (i) discovery of ambiguity in the well-established laws of reflection and refraction of light which have been in regular use for many years, and (ii) discovery of generalized vectorial laws of reflection and refraction of light. The existing definitions of angle of incidence, angle of reflection and angle of refraction are considered first. Each of these definitions is found to be ambiguous, not in compliance with the fundamental definition of angle in geometry. Two typical questions (one in the case of reflection and the other for refraction) have been addressed, which cannot be dealt with by using the existing laws of reflection and refraction of light. Thus, the existing laws of reflection and refraction of light seem to be ambiguous in respect of generality and their validity in a broad sense is questionable. With a view to removing the ambiguities, proper definitions of the above three angles are given first and then the statement of the generalized vectorial law of reflection (as well as that of refraction) has been offered

[Vectorial and congenital transmission of Trypanosoma cruzi in Las Lomitas, Formosa].

Science.gov (United States)

Sosa-Estani, Sergio; Dri, Lucía; Touris, Cecilia; Abalde, Sergio; Dell'arciprete, Ana; Braunstein, Jose

2009-01-01

Chagas disease, caused by Trypanosoma cruzi, is a major cause of morbidity and mortality in Latin America. The objective of this study was to describe the rate of infestation in four aboriginal communities in Las Lomitas (Great Chaco Region), Formosa, Argentina; the rate of infection in children residing in these communities, in blood donors and in pregnant women who received care at the Hospital Las Lomitas, as well as the rate of congenital infection in children born to women infected during the study period. The rate of infestation of 172 households evaluated in 2006 reached 32%. Prevalence of infection among 445 people was 17.5% and in children under 5 years old it was 8.6%. The rate of infection reached 18.6% in blood donors and 29.1% in pregnant women. The rate of infection among 47 children born to infected women, and living in residences under vectorial surveillance was 17.0%. These infections were considered as congenital. This study showed indexes compatible with active vectorial transmission at the beginning. After vectorial control with insecticides the infestation rate has been reduced to 3.3%. The local health system has introduced high impact procedures of primary and secondary prevention in order to prevent new cases and to treat infected people.

Vectorial near-field imaging of a GaN based photonic crystal cavity

International Nuclear Information System (INIS)

La China, F.; Intonti, F.; Caselli, N.; Lotti, F.; Vinattieri, A.; Gurioli, M.; Vico Triviño, N.; Carlin, J.-F.; Butté, R.; Grandjean, N.

2015-01-01

We report a full optical deep sub-wavelength imaging of the vectorial components of the electric local density of states for the confined modes of a modified GaN L3 photonic crystal nanocavity. The mode mapping is obtained with a scanning near-field optical microscope operating in a resonant forward scattering configuration, allowing the vectorial characterization of optical passive samples. The optical modes of the investigated cavity emerge as Fano resonances and can be probed without the need of embedded light emitters or evanescent light coupling into the nanocavity. The experimental maps, independently measured in the two in-plane polarizations, turn out to be in excellent agreement with numerical predictions

Vectorial structures of linear-polarized Butterfly-Gauss vortex beams in the far zone

Science.gov (United States)

Cheng, Ke; Zhou, Yan; Lu, Gang; Yao, Na; Zhong, Xianqiong

2018-05-01

By introducing the Butterfly catastrophe to optics, the far-zone vectorial structures of Butterfly-Gauss beam with vortex and non-vortex are studied using the angular spectrum representation and stationary phase method. The influence of topological charge, linear-polarized angle, off-axis distance and scaling length on the far-zone vectorial structures, especially in the Poynting vector and angular momentum density of the corresponding beam is emphasized. The results show that the embedded optical vortex at source plane lead to special dark zones in the far zone, where the number of dark zone equals the absolute value of topological charge of optical vortex. Furthermore, the symmetry and direction of the special dark zones can be controlled by off-axis distance and scaling length, respectively. The linear-polarized angle adjusts only the Poynting vectors of TE and TM terms, but it does not affect those of whole beam. Finally, the vectorial expressions also indicate that the total angular momentum density is certainly zero owing to the far-zone stable structures rather than rotation behaviors.

Propagation-invariant vectorial Bessel beams by use of sub wavelength quantized Pancharatnam-Berry phase optics

International Nuclear Information System (INIS)

Niv, A.; Biener, G.; Kleiner, V.; Hasman, E.

2004-01-01

Full Text:Propagation-invariant scalar fields have been extensively studied both theoretically and experimentally, since they were proposed by Durnin et al. These fields were employed in applications such as optical tweezers and for transport and guiding of microspheres. Although there has recently been considerable theoretical interest in propagation-invariant vectorial beams, experimental studies of such beams have remained somewhat limited. One of the most interesting types of propagation-invariant vectorial beam is the linearly polarized axially symmetric beam (LPASB) [l]. Recently, we introduced and experimentally demonstrated propagation-invariant vectorial Bessel beams with linearly polarized axial symmetry based on quantized Pancharatnam-Berry phase optical elements (QPBOEs) [21 and an axicon. QP-BOEs utilize the geometric phase that accompanies space-variant polarization manipulations to achieve a desired phase modification [31. To test our approach we formed QPBOEs with different polarization orders as computer-generated space-variant sub wavelength gratings upon GaAs wafers for use with 10.6 micron laser radiation. The resultant beams were also transmitted through a polarizer that produced a unique propagation-invariant scalar beam. This beam has a propeller-shaped intensity pattern that can be rotated by simple rotation of the polarizer. We therefore have demonstrated the formation of a vectorial Bessel beam by using simple, lightweight thin elements and exploited that beam to perform a controlled rotation of a propeller-shaped intensity pattern that can be suitable for optical tweezers

Microbial Pre-exposure and Vectorial Competence of Anopheles Mosquitoes

Directory of Open Access Journals (Sweden)

Constentin Dieme

2017-12-01

Full Text Available Anopheles female mosquitoes can transmit Plasmodium, the malaria parasite. During their aquatic life, wild Anopheles mosquito larvae are exposed to a huge diversity of microbes present in their breeding sites. Later, adult females often take successive blood meals that might also carry different micro-organisms, including parasites, bacteria, and viruses. Therefore, prior to Plasmodium ingestion, the mosquito biology could be modulated at different life stages by a suite of microbes present in larval breeding sites, as well as in the adult environment. In this article, we highlight several naturally relevant scenarios of Anopheles microbial pre-exposure that we assume might impact mosquito vectorial competence for the malaria parasite: (i larval microbial exposures; (ii protist co-infections; (iii virus co-infections; and (iv pathogenic bacteria co-infections. In addition, significant behavioral changes in African Anopheles vectors have been associated with increasing insecticide resistance. We discuss how these ethological modifications may also increase the repertoire of microbes to which mosquitoes could be exposed, and that might also influence their vectorial competence. Studying Plasmodium–Anopheles interactions in natural microbial environments would efficiently contribute to refining the transmission risks.

The importance of an entomo-epidemiological monitoring in the construction of pipelines at the Amazon

Energy Technology Data Exchange (ETDEWEB)

Cruz, Elidianne da S.; Valgas, Luciana L.; Batista, Rita de Cassia G.; Agostini, Lucimara de; Pereira, Andreia Labrea; Freitas, Wanderleia Isabel P. de; Frade, Amadeu Farage [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)

2009-12-19

This work has as objective to evidence one of the consequences of most satisfactory results, talking about attendance to the legal requirements of health on a pipeline undertake at the Amazon: a positive result of index zero of malaria cases until the present days. This work, in its peak, reached the contingent of eight thousand workers lodged in rafts, boats, carps and jungle camps. To reach this index, a methodology of prevention through an entomo epidemiological control was adopted, recommended for the World-wide Organization of Health, as basic activity for malaria control in endemic areas, as in Amazon. The activities had consisted to identify the epidemiologic profile of each area, to elaborate procedures of vectorial control, to implant laboratories for analysis of malaria blades, to enable staff to accomplishment of vectorial control, to realize thermo nebulization and domestic spread and to sensitize the workers of prevention and control measures. Therefore, by means of accomplishment of these basic actions, it was possible to assure an integral, equitable and qualitative attendance providing a critical and conscientious vision of involved and the success of the procedures adopted by PETROBRAS, represented by ENGENHARIA/IENOR (Northern Undertake Implementation), unit responsible for the pipeline Urucu-Manaus Construction. (author)

Ecological and epidemiological status of species of the Phlebotomus perniciosus complex (Diptera: Psychodidae, Phlebotominae) in Morocco.

Science.gov (United States)

Zarrouk, Asmae; Kahime, Kholoud; Boussaa, Samia; Belqat, Boutaïna

2016-03-01

Leishmania infantum (Kinetoplastida: Trypanosomatidae) infection is transmitted by an infected female sand fly (Diptera: Psychodidae, Phlebotominae) of the subgenus Larroussius: Phlebotomus ariasi, Phlebotomus perniciosus, and Phlebotomus longicuspis in the Mediterranean basin. In Morocco, the vectorial role of P. ariasi was demonstrated, while that of P. longicuspis and P. perniciosus is not elucidated. In addition, Moroccan P. longicuspis and P. perniciosus populations present a higher morphologic and genetic variability. It was classified as P. perniciosus complex, including typical (PN) and atypical (PNA) morphs of P. perniciosus, P. longicuspis sensu stricto (LCss), and a sibling species of P. longicuspis (LCx). With the aim to study the ecological and epidemiological status of P. perniciosus complex species in Morocco, entomological surveys were carried out during three entomological seasons (2012, 2013, and 2014). We collected a total of 6298 specimens from 81 localities of northern, central, and southern Morocco. After describing the geographical distribution of P. perniciosus complex trough Morocco according to many variables (altitude, latitude, and longitude), we discuss the resulting epidemiological implications of its species. Our results highlight the geographical distribution of the two morphs of P. perniciosus through Morocco: PN is limited to the north, while PNA is widespread in northern, central, and southern Morocco. In terms of vectorial role, we hypothesize the potential involvement of PN, LCss, and LCx, at least, with P. ariasi, in the epidemiological cycle of L. infantum in Morocco.

2D Poisson sigma models with gauged vectorial supersymmetry

Energy Technology Data Exchange (ETDEWEB)

Bonezzi, Roberto [Dipartimento di Fisica ed Astronomia, Università di Bologna and INFN, Sezione di Bologna,via Irnerio 46, I-40126 Bologna (Italy); Departamento de Ciencias Físicas, Universidad Andres Bello,Republica 220, Santiago (Chile); Sundell, Per [Departamento de Ciencias Físicas, Universidad Andres Bello,Republica 220, Santiago (Chile); Torres-Gomez, Alexander [Departamento de Ciencias Físicas, Universidad Andres Bello,Republica 220, Santiago (Chile); Instituto de Ciencias Físicas y Matemáticas, Universidad Austral de Chile-UACh,Valdivia (Chile)

2015-08-12

In this note, we gauge the rigid vectorial supersymmetry of the two-dimensional Poisson sigma model presented in arXiv:1503.05625. We show that the consistency of the construction does not impose any further constraints on the differential Poisson algebra geometry than those required for the ungauged model. We conclude by proposing that the gauged model provides a first-quantized framework for higher spin gravity.

A vectorial description of electromagnetic scattering by large bodies of spherical shape

International Nuclear Information System (INIS)

Bourrely, C.; Lemaire, T.; Chiappetta, P.; Centre National de la Recherche Scientifique, 13 - Marseille

1989-10-01

We present a new method to obtain a vectorial solution of Helmholtz equation for large homogeneous scatterers having a cylindrical symmetry and a shape approximately spherical. Limitations of the method for arbitrarily shaped particles are discussed

Formas armónicas con valores en un fibrado vectorial e inmersiones de variedades riemannianas

OpenAIRE

Llauce Santamaría, Edwin Edilberto

2014-01-01

El propósito de este trabajo es discutir la aplicación de la teoría de las formas armónicas con valores en un fibrado vectorial y su relación con las inmersiones en una variedad riemanniana. Sea M una variedad riemanniana y E un fibrado vectorial riemanniano sobre M, entonces podemos definir de manera natural el operador laplaciano en las formas diferenciales con valores en E y expresaremos el producto escalar ⟨θ, θ⟩, donde θ es una p-forma con valores en E, en términos de la curvatura y la d...

Full-vectorial propagation model and modified effective mode area of four-wave mixing in straight waveguides

DEFF Research Database (Denmark)

Guo, Kai; Friis, Søren Michael Mørk; Christensen, Jesper Bjerge

2017-01-01

We derive from Maxwell's equations full-vectorial nonlinear propagation equations of four-wave mixing valid in straight semiconductor-on-insulator waveguides. Special attention is given to the resulting effective mode area, which takes a convenient form known from studies in photonic crystal fibers......, but has not been introduced in the context of integrated waveguides. We show that the difference between our full-vectorial effective mode area and the scalar equivalent often referred to in the literature may lead to mistakes when evaluating the nonlinear refractive index and optimizing designs of new...

The membrane-topogenic vectorial behaviour of Nrf1 controls its post-translational modification and transactivation activity.

Science.gov (United States)

Zhang, Yiguo; Hayes, John D

2013-01-01

The integral membrane-bound Nrf1 transcription factor fulfils important functions in maintaining cellular homeostasis and organ integrity, but how it is controlled vectorially is unknown. Herein, creative use of Gal4-based reporter assays with protease protection assays (GRAPPA), and double fluorescence protease protection (dFPP), reveals that the membrane-topogenic vectorial behaviour of Nrf1 dictates its post-translational modification and transactivation activity. Nrf1 is integrated within endoplasmic reticulum (ER) membranes through its NHB1-associated TM1 in cooperation with other semihydrophobic amphipathic regions. The transactivation domains (TADs) of Nrf1, including its Asn/Ser/Thr-rich (NST) glycodomain, are transiently translocated into the ER lumen, where it is glycosylated in the presence of glucose to become a 120-kDa isoform. Thereafter, the NST-adjoining TADs are partially repartitioned out of membranes into the cyto/nucleoplasmic side, where Nrf1 is subject to deglycosylation and/or proteolysis to generate 95-kDa and 85-kDa isoforms. Therefore, the vectorial process of Nrf1 controls its target gene expression.

Álgebra vectorial y geometría euclidiana

OpenAIRE

Salazar Caicedo, José Alonso

1992-01-01

Las leyes del álgebra vectorial asociadas al conjunto de los segmentos dirigidos del plano (o del espacio), en conexión con un producto interior, permiten demostrar una gran variedad de proposiciones y teoremas de la geometría clásica euclidiana, utilizando procedimientos y técnicas relativamente simples. Desde un punto de vista didáctico y pedagógico, surge el problema de examinar hasta qué punto es posible recuperar gran parte del arsenal de ideas fructíferas que proporcionaban a otras g...

Advanced vectorial simulation of VCSELs with nano structures invited paper

DEFF Research Database (Denmark)

Chung, Il-Sug; Mørk, Jesper

2009-01-01

The single-mode properties and design issues of three vertical-cavity surface-emitting laser (VCSEL) structures incorporating nano structures are rigorously investigated. Nano structuring enables to deliver selective pumping or loss to the fundamental mode as well as stabilizing the output...... polarization state. Comparison of three vectorial simulation methods reveals that the modal expansion method is suitable for treating the nano structured VCSEL designs....

Evidence of vectorial photoelectric effect on Copper

International Nuclear Information System (INIS)

Pedersoli, E.; Banfi, F.; Ressel, B.; Pagliara, S.; Giannetti, C.; Galimberti, G.; Lidia, S.; Corlett, J.; Ferrini, G.; Parmigiani, F.

2005-01-01

Quantum efficiency (QE) measurements of single photon photoemission from a Cu(111) single crystal and a Cu polycrystal photocathodes, irradiated by 150 fs-6.28 eV laser pulses, are reported over a broad range of incidence angle, both in s and p polarizations. The maximum QE (≅4x10 -4 ) for polycrystalline Cu is obtained in p polarization at an angle of incidence θ=65 deg. . We observe a QE enhancement in p polarization which cannot be explained in terms of optical absorption, a phenomenon known as vectorial photoelectric effect. Issues concerning surface roughness and symmetry considerations are addressed. An explanation in terms of nonlocal conductivity tensor is proposed

Dynamical breakdown of chiral symmetry in vectorial theories: QED and QCD

International Nuclear Information System (INIS)

Garcia, J.C.M.

1987-01-01

Using a variational approach for the Effective Potential for composite operators we dicuss the dynamical breakdown of chiral symmetry in two vectorial theories: Quantum Electrodynamics (QED) and Quantum Chromodynamics (QCD). We study the energetic aspects of the problem calculating the Effective Potential with the asymptotic nonperturbative solutions of the Schwinger-Dyson equation for the fermion selfenergy. (author) [pt

Synthesis of focused beam with controllable arbitrary homogeneous polarization using engineered vectorial optical fields.

Science.gov (United States)

Rui, Guanghao; Chen, Jian; Wang, Xiaoyan; Gu, Bing; Cui, Yiping; Zhan, Qiwen

2016-10-17

The propagation and focusing properties of light beams continue to remain a research interest owning to their promising applications in physics, chemistry and biological sciences. One of the main challenges to these applications is the control of polarization distribution within the focal volume. In this work, we propose and experimentally demonstrate a method for generating a focused beam with arbitrary homogeneous polarization at any transverse plane. The required input field at the pupil plane of a high numerical aperture objective lens can be found analytically by solving an inverse problem with the Richard-Wolf vectorial diffraction method, and can be experimentally created with a vectorial optical field generator. Focused fields with various polarizations are successfully generated and verified using a Stokes parameter measurement to demonstrate the capability and versatility of proposed technique.

The vectorial photoelectric effect under solar irradiance and its application to sun sensing

International Nuclear Information System (INIS)

Hechenblaikner, Gerald; Ziegler, Tobias

2014-01-01

Sun sensors are an integral part of the attitude and orbit control system onboard almost any spacecraft. While the majority of standard analogue sun sensors is based on photo-detectors which produce photo-currents proportional to the cosine of the incidence angle (cosine detectors), we propose an alternative scheme where the vectorial photoelectric effect is exploited to achieve a higher sensitivity of the sensed photo-current to the incidence angle. The vectorial photo-effect is investigated in detail for metal cathode detectors in a space environment. Besides long operational lifetimes without significant degradation, metal cathode detectors are insensitive to earth albedo, which may significantly reduce the errors affecting attitude measurements in low earth orbits. Sensitivity curves are calculated and trade-offs performed with the aim of optimizing the sensitivity whilst also providing currents sufficient for detection. Simple applications and detector configurations are also discussed and compared to the existing designs. (paper)

[Dynamic study of the female levator ani muscle using MRI 3D vectorial modeling].

Science.gov (United States)

Delmas, Vincent; Ami, Olivier; Iba-Zizen, Marie-Thérèse

2010-06-01

The levator ani muscle has a major role in the female pelvic floor, and is involved in the pathophysiology of pelvic prolapse and stress urinary incontinence. We conducted an anatomical and morphological study of this muscle using dynamic 3D vectorial reconstruction MRI, in order to analyze the contraction of two major components of the levator ani: the iliococcygeus and pubococcygeus. Three volunteer healthy continent nulliparous women aged from 19 to 22 underwent dynamic pelvic MRI. Coronal T2-weighted pelvic images were obtained in the supine position, at rest, holding back, and during Valsalva stress effort. 3D vectorial models were reconstructed by manual segmentation of the source images, and were set up on bony anatomic marks. Iliococcygeus and pubococcygeus volumes were measured in the three positions. Volumetrics, displacement and dynamic morphing changes were analyzed with 3D vectorial animation software. The urogenital hiatus extended more holding back (mean +4.31 mm) than on effort (mean +2.78 mm). The iliococcygeus lowered (mean -3.95 mm) and deviated outward (mean +3.01 mm). The basic tone of the iliococcygeus muscle gives it a dome shape, and its reflex contraction against abdominal strain ensures anal and urinary continence The levator ani is more than a pelvic diaphragm: it is a truly dynamic pelvic floor. Its points of support on the stiff osseous frame allow it to retain the pelvic organs. The levator ani muscle seems to prevent anal prolapse during stress strain.

First report of autochthonous non-vectorial canine leishmaniasis in New Caledonia, south-western Pacific: implications for new control measures and recommendations on importation of dogs.

Science.gov (United States)

Daval, Nathalie; Marchal, Céline; Guillaumot, Laurent; Hüe, Thomas; Ravel, Christophe; Keck, Nicolas; Kasbari, Mohamed

2016-02-25

Canine leishmaniasis (CanL), a parasitic zoonotic disease caused by Leishmania infantum and usually transmitted by phlebotomine sandflies, has rarely been reported in Pacific islands, which have been regarded until now as leishmaniasis-free territory. Here, we report the first autochthonous CanL case in New Caledonia (south-western Pacific) and the investigations carried out 1) to determine how infection was introduced into and transmitted among these dogs and 2) to assess the risks to animal and public health. Extensive epidemiological and entomological investigations in and around the focus were carried out. Leishmaniasis infection was confirmed by histopathology, indirect fluorescent antibody test, real-time PCR, and culture. Parasite strain was typed by the isoenzymatic technique. The survey revealed close contacts between the autochthonous dog and two infected bitches imported from Spain, but failed to find any possible vector or disease spreading to other animals or humans. L. infantum zymodeme MON-1, the most frequent type in the Mediterranean basin, was identified. Although transplacental and venereal transmissions could not be excluded, the evidence was in favour of non-vectorial, direct dog-to-dog transmission. This study corroborates the possibility of non-vectorial routes (transplacental, venereal, and direct dog-to-dog) of canine leishmaniasis transmission in New Caledonia and raises the debate of relevant test requirements and diagnostic sensitivity prior to importation of dogs in Leishmania-free regions. New leishmaniasis control measures and recommendations to avoid future CanL introduction on the island are discussed.

Polarimetric and angular light-scattering from dense media: Comparison of a vectorial radiative transfer model with analytical, stochastic and experimental approaches

International Nuclear Information System (INIS)

Riviere, Nicolas; Ceolato, Romain; Hespel, Laurent

2013-01-01

Our work presents computations via a vectorial radiative transfer model of the polarimetric and angular light scattered by a stratified dense medium with small and intermediate optical thickness. We report the validation of this model using analytical results and different computational methods like stochastic algorithms. Moreover, we check the model with experimental data from a specific scatterometer developed at the Onera. The advantages and disadvantages of a radiative approach are discussed. This paper represents a step toward the characterization of particles in dense media involving multiple scattering. -- Highlights: • A vectorial radiative transfer model to simulate the light scattered by stratified layers is developed. • The vectorial radiative transfer equation is solved using an adding–doubling technique. • The results are compared to analytical and stochastic data. • Validation with experimental data from a scatterometer developed at Onera is presented

Central African Field Epidemiology and Laboratory Training Program: building and strengthening regional workforce capacity in public health.

Science.gov (United States)

Andze, Gervais Ondobo; Namsenmo, Abel; Illunga, Benoit Kebella; Kazambu, Ditu; Delissaint, Dieula; Kuaban, Christopher; Mbopi-Kéou, Francois-Xavier; Gabsa, Wilfred; Mulumba, Leopold; Bangamingo, Jean Pierre; Ngulefac, John; Dahlke, Melissa; Mukanga, David; Nsubuga, Peter

2011-01-01

The Central African Field Epidemiology and Laboratory Training Program (CAFELTP) is a 2-year public health leadership capacity building training program. It was established in October 2010 to enhance capacity for applied epidemiology and public health laboratory services in three countries: Cameroon, Central African Republic, and the Democratic Republic of Congo. The aim of the program is to develop a trained public health workforce to assure that acute public health events are detected, investigated, and responded to quickly and effectively. The program consists of 25% didactic and 75% practical training (field based activities). Although the program is still in its infancy, the residents have already responded to six outbreak investigations in the region, evaluated 18 public health surveillance systems and public health programs, and completed 18 management projects. Through these various activities, information is shared to understand similarities and differences in the region leading to new and innovative approaches in public health. The program provides opportunities for regional and international networking in field epidemiology and laboratory activities, and is particularly beneficial for countries that may not have the immediate resources to host an individual country program. Several of the trainees from the first cohort already hold leadership positions within the ministries of health and national laboratories, and will return to their assignments better equipped to face the public health challenges in the region. They bring with them knowledge, practical training, and experiences gained through the program to shape the future of the public health landscape in their countries.

The vectorial control of magnetization by light.

Science.gov (United States)

Kanda, Natsuki; Higuchi, Takuya; Shimizu, Hirokatsu; Konishi, Kuniaki; Yoshioka, Kosuke; Kuwata-Gonokami, Makoto

2011-06-21

Application of coherent light-matter interactions has recently been extended to the ultrafast control of magnetization. An important but unrealized technique is the manipulation of magnetization vector motion to make it follow an arbitrarily designed multidimensional trajectory. Here we demonstrate a full manipulation of two-dimensional magnetic oscillations in antiferromagnetic NiO with a pair of polarization-twisted femtosecond laser pulses. We employ Raman-type nonlinear optical processes, wherein magnetic oscillations are impulsively induced with a controlled initial phase. Their azimuthal angle follows well-defined selection rules that have been determined by the symmetries of the materials. We emphasize that the temporal variation of the laser-pulse polarization angle enables us to control the phase and amplitude of the two degenerate modes, independently. These results lead to a new concept of the vectorial control of magnetization by light.

Vectorial Modeling Of NH In Comet 2P/Encke

Science.gov (United States)

Dorman, Garrett; Pierce, D.; Cochran, A.

2010-10-01

Encke is an ideal comet for studying the relationship of radicals to their photodissociative parent molecules due to its low dust content. On 2003 October 22 - 24, we used the the 2.7 m telescope at the McDonald Observatory of the University of Texas to obtain spectra of several cometary radical species. Using a version of the Vectorial Model that has been modified to simulate Encke's prominent sunward-facing fan, we examined the spacial distribution of NH in the coma. Potential photochemical parents of NH were studied in order to understand its production and spacial distribution in the coma. Derived production rates are compared to values in other comets to constrain the primary parent of NH in Encke.

Phlebotomus (Paraphlebotomus) riouxi: a synonym of Phlebotomus chabaudi without any proven vectorial role in Tunisia and Algeria.

Science.gov (United States)

Tabbabi, A; Rhim, A; Ghrab, J; Martin, O; Aoun, K; Bouratbine, A; Ready, P D

2014-08-01

Phlebotomus (Paraphlebotomus) riouxi Depaquit, Léger & Killick-Kendrick (Diptera: Psychodidae) was described as a typological species based on a few morphological characters distinguishing it from Phlebotomus (Paraphlebotomus) chabaudi Croset, Abonnenc & Rioux. The naming of P. riouxi coincided with its incrimination as a rural vector of Leishmania tropica Wright (junior synonym: Leishmania killicki Rioux, Lanotte & Pratlong) in Tataouine governorate, an arid region of southern Tunisia. The current report finds insufficient evidence to incriminate either phlebotomine sandfly as a vector of L. tropica in North Africa. Phlebotomus riouxi was found not to have the characteristics of a phylogenetic or biological species, and therefore it is synonymized with P. chabaudi. Both taxa were recorded together for the first time in Tunisia, in Tataouine, where three of 12 males showed intermediate morphology and both sexes of each taxon were not characterized by specific lineages of the nuclear gene elongation factor-1α or the mitochondrial gene cytochrome b, for which a long 3' terminal fragment is recommended for phlebotomine phylogenetics. This case study indicates that the eco-epidemiology of leishmaniasis should focus more on identifying key components of vectorial transmission that are susceptible to interventions for disease control, rather than on defining sibling species of vectors. © 2014 The Royal Entomological Society.

The role of 'filth flies' in the spread of antimicrobial resistance

DEFF Research Database (Denmark)

Onwugamba, Francis C.; Fitzgerald, J. Ross; Rochon, Kateryn

2018-01-01

Background: 'Filth flies' feed and develop in excrement and decaying matter and can transmit enteric pathogens to humans and animals, leading to colonization and infection. Considering these characteristics, 'filth flies' are potential vectors for the spread of antimicrobial resistance (AMR...... spots. Conclusion: To better understand the medical importance of AMR in flies, quantitative risk assessment models should be refined and fed with additional data (e.g. vectorial capacity, colonization dose). This requires targeted ecological, epidemiological and in vivo experimental studies....

Simulació de tècniques de control vectorial d'un motor síncron

OpenAIRE

Valls Peralbo, Víctor

2016-01-01

L'objecte del projecte és simular diferents tècniques de control vectorial d'una màquina síncrona d’ imants permanents funcionant com a motor a l'entorn Matlab-Simulink. Es buscarà un mètode de control que permeti que la intensitat directe de la intensitat de camp sigui igual a zero

Demonstration of a vectorial optical field generator with adaptive close loop control.

Science.gov (United States)

Chen, Jian; Kong, Lingjiang; Zhan, Qiwen

2017-12-01

We experimentally demonstrate a vectorial optical field generator (VOF-Gen) with an adaptive close loop control. The close loop control capability is illustrated with the calibration of polarization modulation of the system. To calibrate the polarization ratio modulation, we generate 45° linearly polarized beam and make it propagate through a linear analyzer whose transmission axis is orthogonal to the incident beam. For the retardation calibration, circularly polarized beam is employed and a circular polarization analyzer with the opposite chirality is placed in front of the CCD as the detector. In both cases, the close loop control automatically changes the value of the corresponding calibration parameters in the pre-set ranges to generate the phase patterns applied to the spatial light modulators and records the intensity distribution of the output beam by the CCD camera. The optimized calibration parameters are determined corresponding to the minimum total intensity in each case. Several typical kinds of vectorial optical beams are created with and without the obtained calibration parameters, and the full Stokes parameter measurements are carried out to quantitatively analyze the polarization distribution of the generated beams. The comparisons among these results clearly show that the obtained calibration parameters could remarkably improve the accuracy of the polarization modulation of the VOF-Gen, especially for generating elliptically polarized beam with large ellipticity, indicating the significance of the presented close loop in enhancing the performance of the VOF-Gen.

Highly evolvable malaria vectors : The genomes of 16 Anopheles mosquitoes

NARCIS (Netherlands)

Neafsey, D. E.; Waterhouse, R. M.; Abai, M. R.; Aganezov, S. S.; Alekseyev, M. A.; Allen, J. E.; Amon, J.; Arca, B.; Arensburger, P.; Artemov, G.; Assour, L. A.; Basseri, H.; Berlin, A.; Birren, B. W.; Blandin, S. A.; Brockman, A. I.; Burkot, T. R.; Burt, A.; Chan, C. S.; Chauve, C.; Chiu, J. C.; Christensen, M.; Costantini, C.; Davidson, V. L. M.; Deligianni, E.; Dottorini, T.; Dritsou, V.; Gabriel, S. B.; Guelbeogo, W. M.; Hall, A. B.; Han, M. V.; Hlaing, T.; Hughes, D. S. T.; Jenkins, A. M.; Jiang, X.; Jungreis, I.; Kakani, E. G.; Kamali, M.; Kemppainen, P.; Kennedy, R. C.; Kirmitzoglou, I. K.; Koekemoer, L. L.; Laban, N.; Langridge, N.; Lawniczak, M. K. N.; Lirakis, M.; Lobo, N. F.; Lowy, E.; Maccallum, R. M.; Mao, C.; Maslen, G.; Mbogo, C.; Mccarthy, J.; Michel, K.; Mitchell, S. N.; Moore, W.; Murphy, K. A.; Naumenko, A. N.; Nolan, T.; Novoa, E. M.; O'loughlin, S.; Oringanje, C.; Oshaghi, M. A.; Pakpour, N.; Papathanos, P. A.; Peery, A. N.; Povelones, M.; Prakash, A.; Price, D. P.; Rajaraman, A.; Reimer, L. J.; Rinker, D. C.; Rokas, A.; Russell, T. L.; Sagnon, N.; Sharakhova, M. V.; Shea, T.; Simao, F. A.; Simard, F.; Slotman, M. A.; Somboon, P.; Stegniy, V.; Struchiner, C. J.; Thomas, G. W. C.; Tojo, M.; Topalis, P.; Tubio, J. M. C.; Unger, M. F.; Vontas, J.; Walton, C.; Wilding, C. S.; Willis, J. H.; Wu, Y.-c.; Yan, G.; Zdobnov, E. M.; Zhou, X.; Catteruccia, F.; Christophides, G. K.; Collins, F. H.; Cornman, R. S.; Crisanti, A.; Donnelly, M. J.; Emrich, S. J.; Fontaine, M. C.; Gelbart, W.; Hahn, M. W.; Hansen, I. A.; Howell, P. I.; Kafatos, F. C.; Kellis, M.; Lawson, D.; Louis, C.; Luckhart, S.; Muskavitch, M. A. T.; Ribeiro, J. M.; Riehle, M. A.; Sharakhov, I. V.; Tu, Z.; Zwiebel, L. J.; Besansky, N. J.

2015-01-01

Variation in vectorial capacity for human malaria among Anopheles mosquito species is determined by many factors, including behavior, immunity, and life history. To investigate the genomic basis of vectorial capacity and explore new avenues for vector control, we sequenced the genomes of 16

Possible implication of the genetic composition of the Lutzomyia longipalpis (Diptera: Psychodidae) populations in the epidemiology of the visceral leishmaniasis.

Science.gov (United States)

Rocha, Leonardo de Souza; Falqueto, Aloisio; Dos Santos, Claudiney Biral; Grimaldi, Gabriel Júnior; Cupolillo, Elisa

2011-09-01

Lutzomyia longipalpis (Diptera: Psychodidae) is the principal vector of American visceral leishmaniasis. Several studies have indicated that the Lu. longipalpis population structure is complex. It has been suggested that genetic divergence caused by genetic drift, selection, or both may affect the vectorial capacity of Lu. longipalpis. However, it remains unclear whether genetic differences among Lu. longipalpis populations are directly implicated in the transmission features of visceral leishmaniasis. We evaluated the genetic composition and the patterns of genetic differentiation among Lu. longipalpis populations collected from regions with different patterns of transmission of visceral leishmaniasis by analyzing the sequence variation in the mitochondrial cytochrome b gene. Furthermore, we investigated the temporal distribution of haplotypes and compared our results with those obtained in a previous study. Our data indicate that there are differences in the haplotype composition and that there has been significant differentiation between the analyzed populations. Our results reveal that measures used to control visceral leishmaniasis might have influenced the genetic composition of the vector population. This finding raises important questions concerning the epidemiology of visceral leishmaniasis, because these differences in the genetic structures among populations of Lu. longipalpis may have implications with respect to their efficiency as vectors for visceral leishmaniasis.

Participatory epidemiology: the contribution of participatory research to epidemiology

Directory of Open Access Journals (Sweden)

Mario Bach

2017-02-01

Full Text Available Abstract Background Epidemiology has contributed in many ways to identifying various risk factors for disease and to promoting population health. However, there is a continuing debate about the ability of epidemiology not only to describe, but also to provide results which can be better translated into public health practice. It has been proposed that participatory research approaches be applied to epidemiology as a way to bridge this gap between description and action. A systematic account of what constitutes participatory epidemiology practice has, however, been lacking. Methods A scoping review was carried out focused on the question of what constitutes participatory approaches to epidemiology for the purpose of demonstrating their potential for advancing epidemiologic research. Relevant databases were searched, including both the published and non-published (grey literature. The 102 identified sources were analyzed in terms of comparing common epidemiologic approaches to participatory counterparts regarding central aspects of the research process. Exemplary studies applying participatory approaches were examined more closely. Results A highly diverse, interdisciplinary body of literature was synthesized, resulting in a framework comprised of seven aspects of the research process: research goal, research question, population, context, data synthesis, research management, and dissemination of findings. The framework specifies how participatory approaches not only differ from, but also how they can enhance common approaches in epidemiology. Finally, recommendations for the further development of participatory approaches are given. These include: enhancing data collection, data analysis, and data validation; advancing capacity building for research at the local level; and developing data synthesis. Conclusion The proposed framework provides a basis for systematically developing the emergent science of participatory epidemiology.

Reduction of product platform complexity by vectorial Euclidean algorithm

International Nuclear Information System (INIS)

Navarrete, Israel Aguilera; Guzman, Alejandro A. Lozano

2013-01-01

In traditional machine, equipment and devices design, technical solutions are practically independent, thus increasing designs cost and complexity. Overcoming this situation has been tackled just using designer's experience. In this work, a product platform complexity reduction is presented based on a matrix representation of technical solutions versus product properties. This matrix represents the product platform. From this matrix, the Euclidean distances among technical solutions are obtained. Thus, the vectorial distances among technical solutions are identified in a new matrix of order of the number of technical solutions identified. This new matrix can be reorganized in groups with a hierarchical structure, in such a way that modular design of products is now more tractable. As a result of this procedure, the minimum vector distances are found thus being possible to identify the best technical solutions for the design problem raised. Application of these concepts is shown with two examples.

Cálculo vectorial discreto para problemas elípticos sobre retículas uniformes

OpenAIRE

Santos Gutiérrez, Roberto

2004-01-01

Esta tesina se enmarca dentro de los trabajos en el campo del análisis numérico denominados genéricamente como "discretizaciones miméticas de la mecánica del medio continuo". La idea consiste en establecer un cálculo vectorial sobre retículas uniformes siguiendo el modelo del caso continuo, de forma que se plantean los problemas elípticos directamente en medios discretos. Esto conduce a obtener operadores discretos análogos al gradiente, divergencia y laplaciano, y se demuestra que estos oper...

Mitochondrial Physiology in the Major Arbovirus Vector Aedes aegypti: Substrate Preferences and Sexual Differences Define Respiratory Capacity and Superoxide Production

Science.gov (United States)

Soares, Juliana B. R. Correa; Gaviraghi, Alessandro; Oliveira, Marcus F.

2015-01-01

Adult females of Aedes aegypti are facultative blood sucking insects and vectors of Dengue and yellow fever viruses. Insect dispersal plays a central role in disease transmission and the extremely high energy demand posed by flight is accomplished by a very efficient oxidative phosphorylation process, which take place within flight muscle mitochondria. These organelles play a central role in energy metabolism, interconnecting nutrient oxidation to ATP synthesis, but also represent an important site of cellular superoxide production. Given the importance of mitochondria to cell physiology, and the potential contributions of this organelle for A. aegypti biology and vectorial capacity, here, we conducted a systematic assessment of mitochondrial physiology in flight muscle of young adult A. aegypti fed exclusively with sugar. This was carried out by determining the activities of mitochondrial enzymes, the substrate preferences to sustain respiration, the mitochondrial bioenergetic efficiency and capacity, in both mitochondria-enriched preparations and mechanically permeabilized flight muscle in both sexes. We also determined the substrates preferences to promote mitochondrial superoxide generation and the main sites where it is produced within this organelle. We observed that respiration in A. aegypti mitochondria was essentially driven by complex I and glycerol 3 phosphate dehydrogenase substrates, which promoted distinct mitochondrial bioenergetic capacities, but with preserved efficiencies. Respiration mediated by proline oxidation in female mitochondria was strikingly higher than in males. Mitochondrial superoxide production was essentially mediated through proline and glycerol 3 phosphate oxidation, which took place at sites other than complex I. Finally, differences in mitochondrial superoxide production among sexes were only observed in male oxidizing glycerol 3 phosphate, exhibiting higher rates than in female. Together, these data represent a significant step

Local health department epidemiologic capacity: a stratified cross-sectional assessment describing the quantity, education, training, and perceived competencies of epidemiologic staff.

Science.gov (United States)

O'Keefe, Kaitlin A; Shafir, Shira C; Shoaf, Kimberley I

2013-01-01

Local health departments (LHDs) must have sufficient numbers of staff functioning in an epidemiologic role with proper education, training, and skills to protect the health of communities they serve. This pilot study was designed to describe the composition, training, and competency level of LHD staff and examine the hypothesis that potential disparities exist between LHDs serving different sized populations. Cross-sectional surveys were conducted with directors and epidemiologic staff from a sample of 100 LHDs serving jurisdictions of varied sizes. Questionnaires included inquiries regarding staff composition, education, training, and measures of competency modeled on previously conducted studies by the Council of State and Territorial Epidemiologists. Number of epidemiologic staff, academic degree distribution, epidemiologic training, and both director and staff confidence in task competencies were calculated for each LHD size strata. Disparities in measurements were observed in LHDs serving different sized populations. LHDs serving small populations reported a smaller average number of epidemiologic staff than those serving larger jurisdictions. As size of population served increased, percentages of staff and directors holding bachelors' and masters' degrees increased, while those holding RN degrees decreased. A higher degree of perceived competency of staff in most task categories was reported in LHDs serving larger populations. LHDs serving smaller populations reported fewer epidemiologic staff, therefore might benefit from additional resources. Differences observed in staff education, training, and competencies suggest that enhanced epidemiologic training might be particularly needed in LHDs serving smaller populations. RESULTS can be used as a baseline for future research aimed at identifying areas where training and personnel resources might be particularly needed to increase the capabilities of LHDs.

[Current status of the knowledge on Moroccan anophelines (Diptera: Culicidae): systematic, geographical distribution and vectorial competence].

Science.gov (United States)

Faraj, C; Ouahabi, S; Adlaoui, E; Elaouad, R

2010-10-01

This bibliographical study, based on published works, ministry of Health Reports, exploitation of the database relative to the entomological surveillance conducted in the framework of the National Malaria Control Program, as well as unpublished results obtained within the framework of the European project "Emerging disease in a changing European environment", summarizes and completes with new data current knowledge on the systematics, the distribution and the vectorial competence of moroccan anophelines. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

Framework for rapid assessment and adoption of new vector control tools.

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Vontas, John; Moore, Sarah; Kleinschmidt, Immo; Ranson, Hilary; Lindsay, Steve; Lengeler, Christian; Hamon, Nicholas; McLean, Tom; Hemingway, Janet

2014-04-01

Evidence-informed health policy making is reliant on systematic access to, and appraisal of, the best available research evidence. This review suggests a strategy to improve the speed at which evidence is gathered on new vector control tools (VCTs) using a framework based on measurements of the vectorial capacity of an insect population to transmit disease. We explore links between indicators of VCT efficacy measurable in small-scale experiments that are relevant to entomological and epidemiological parameters measurable only in large-scale proof-of-concept randomised control trials (RCTs). We hypothesise that once RCTs establish links between entomological and epidemiological indicators then rapid evaluation of new products within the same product category may be conducted through smaller scale experiments without repetition of lengthy and expensive RCTs. Copyright © 2014 Elsevier Ltd. All rights reserved.

Basic concepts of epidemiology

International Nuclear Information System (INIS)

Savitz, D.A.

1984-01-01

Epidemiology can be defined simply as the science of the distribution and determinants of disease in human populations. As a descriptive tool, epidemiology can aid health care service providers, for example, in allocation of resources. In its analytic capacity, the epidemiologic approach can help identify determinants of disease through the study of human populations. Epidemiology is primarily an observational rather than experimental methodology, with corresponding strengths and limitations. Relative to other approaches for assessing disease etiology and impacts of potential health hazards, epidemiology has a rather unique role that is complementary to, but independent of, both basic biologic sciences and clinical medicine. Experimental biologic sciences such as toxicology and physiology provide critical information on biologic mechanisms of disease required for causal inference. Clinical medicine often serves as the warning system that provides etiologic clues to be pursued through systematic investigation. The advantage of the epidemiologic approach is its reliance on human field experience, that is, the real world. While laboratory experimentation is uniquely well suited to defining potential hazards, it can neither determine whether human populations have actually been affected nor quantify that effect. Building all the complexities of human behavior and external factors into a laboratory study or mathematical model is impossible. By studying the world as it exists, epidemiology examines the integrated, summarized product of the myriad factors influencing health

Estudo da competência vetorial de Lutzomyia intermedia (Lutz & Neiva, 1912 para Leishmania (Viannia braziliensis, Vianna, 1911 Study of the vectorial competence of Lutzomyia intermedia (Lutz & Neiva, 1912 to Leishmania (Viannia braziliensis, Vianna, 1911

Directory of Open Access Journals (Sweden)

Antonio Carlos da Silva

2001-04-01

Full Text Available Estudou-se a competência vetorial de Lutzomyia intermedia (Diptera: Psychodidae do Vale do Ribeira (SP para estirpes de Leishmania (Viannia braziliensis (Kinetoplastida: Trypanosomatidae, mediante pesquisa de infectividade natural; exposições de fêmeas silvestres e colonizadas (F1 às lesões de hamsters experimentalmente infectados e testes de transmissão via picada. A infectividade natural e os testes de transmissão revelaram-se negativos e, nas exposições, foram obtidas positividades de 74% (123+/166 dissecados e 70% (115+/164 dissecados para fêmeas silvestres e colonizadas respectivamente, e o desenvolvimento das formas evolutivas compatíveis com o modelo Peripilaria. A suscetibilidade às estirpes testadas associada aos indicadores epidemiológicos concorrem para a suspeita do papel vetorial de Lutzomyia intermedia na região estudada.This paper investigated the vectorial competence of Lutzomyia intermedia (Diptera: Psychodidae in Vale do Ribeira (SP to strains of Leishmania (Viannia braziliensis (Kinetoplastida: Trypanosomatidae, by means of a search for natural infection; exposure of wild and colonized females (F1 to the lesions of experimentally infected hamsters and transmission tests by bite. The natural infection and the transmission tests were negative. In the exposures of Lu. intermedia to infected lesions we found rates of 74% (123+/166 dissected and 70% (115+/164 dissected for the wild and colonized females respectively. The development of the parasites was compatible with the development model of Peripilaria. The susceptibility of the tested strains associated with the epidemiological indicators contribute to the vectorial role suspicion of Lutzomyia intermedia in the studied region.

Mode-selective mapping and control of vectorial nonlinear-optical processes in multimode photonic-crystal fibers.

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Hu, Ming-Lie; Wang, Ching-Yue; Song, You-Jian; Li, Yan-Feng; Chai, Lu; Serebryannikov, Evgenii; Zheltikov, Aleksei

2006-02-06

We demonstrate an experimental technique that allows a mapping of vectorial nonlinear-optical processes in multimode photonic-crystal fibers (PCFs). Spatial and polarization modes of PCFs are selectively excited in this technique by varying the tilt angle of the input beam and rotating the polarization of the input field. Intensity spectra of the PCF output plotted as a function of the input field power and polarization then yield mode-resolved maps of nonlinear-optical interactions in multimode PCFs, facilitating the analysis and control of nonlinear-optical transformations of ultrashort laser pulses in such fibers.

Vectorial competence of larvae and adults of Alphitobius diaperinus in the transmission of Salmonella enteritidis in poultry.

Science.gov (United States)

Leffer, Andreia M; Kuttel, Javier; Martins, Lidiane M; Pedroso, Antonio Carlos; Astolfi-Ferreira, Claudete S; Ferreira, Fernando; Ferreira, Antonio J Piantino

2010-06-01

The ingestion of food products originating from poultry infected with Salmonella spp. is one of the major causes of food poisoning in humans. The control of poultry salmonellosis is particularly difficult since birds are asymptomatic and numerous factors may expedite the maintenance of bacteria in poultry production facilities. The aim of the study was to determine the vectorial capacity of adults and larvae of Alphitobius diaperinus (Coleoptera: Tenebrionidae) in the experimental transmission of Salmonella Enteritidis phage type 4 to 1-day-old specific pathogen-free White Leghorn chicks. Adult insects and larvae were starved for 1 day, fed for 24 h or 7 days on sterile ration that had been treated with Salmonella Enteritidis phage type 4, and the levels of bacterial infection were determined. Infected adult insects and larvae were fed to groups of day-old chicks, after which bacteria were recovered from cecum, liver, and spleen samples over a 7-day period. Infected larvae were more efficient than adult insects in transmitting Salmonella Enteritidis to chicks. Higher concentrations of bacteria could be reisolated from the cecum, liver, and spleen of chicks that had ingested infected larvae compared with those that had ingested infected adults. The control of A. diaperinus, and particularly of the larvae, represents a critical factor in the reduction of Salmonella spp. in poultry farms.

Current practice of epidemiology in Africa: highlights of the 3rd conference of the African epidemiological association and 1st conference of the Cameroon society of epidemiology, Yaoundé, Cameroon, 2014.

Science.gov (United States)

Nkwescheu, Armand Seraphin; Fokam, Joseph; Tchendjou, Patrice; Nji, Akindeh; Ngouakam, Hermann; Andre, Bita Fouda; Joelle, Sobngwi; Uzochukwu, Benjamin; Akinroye, Kingsley; Mbacham, Wilfred; Colizzi, Vittorio; Leke, Rose; Victora, Cesar

2015-01-01

As the study of disease occurrence and health indicators in human populations, Epidemiology is a dynamic field that evolves with time and geographical context. In order to update African health workers on current epidemiological practices and to draw awareness of early career epidemiologists on concepts and opportunities in the field, the 3(rd) African Epidemiology Association and the 1st Cameroon Society of Epidemiology Conference was organized in June 2-6, 2014 at the Yaoundé Mont Febe Hotel, in Cameroon. Under the theme«Practice of Epidemiology in Africa: Stakes, Challenges and Perspectives», the conference attracted close to five hundred guest and participants from all continents. The two main programs were the pre-conference course for capacity building of African Early Career epidemiologists, and the conference itself, providing a forum for scientific exchanges on recent epidemiological concepts, encouraging the use of epidemiological methods in studying large disease burden and neglected tropical diseases; and highlighting existing opportunities.

Stoichiometry of vectorial H+ movements coupled to electron transport and to ATP synthesis in mitochondria

Science.gov (United States)

Alexandre, Adolfo; Reynafarje, Baltazar; Lehninger, Albert L.

1978-01-01

In order to verify more directly our earlier measurements showing that, on the average, close to four vectorial H+ are rejected per pair of electrons passing each of the three energy-conserving sites of the mitochondrial electron transport chain, direct tests of the H+/2e- ratio for sites 2 and 3 were carried out in the presence of permeant charge-compensating cations. Site 2 was examined by utilizing succinate as electron donor and ferricyanide as electron acceptor from mitochondrial cytochrome c; the directly measured H+/2e- ratio was close to 4. Energy-conserving site 3 was isolated for study with ferrocyanide or ascorbate plus tetramethylphenylenediamine as electron donors to cytochrome c and with oxygen as electron acceptor. The directly measured H+/2e- ratio for site 3 was close to 4. The H+/ATP ratio (number of vectorial H+ ejected per ATP hydrolyzed) was determined with a new method in which the steady-state rates of both H+ ejection and ATP hydrolysis were measured in the presence of K+ + valinomycin. The H+/ATP ratio was found to approach 3.0. A proton cycle for oxidative phosphorylation is proposed, in which four electrochemical H+ equivalents are ejected per pair of electrons passing each energy-conserving site; three of the H+ equivalents pass inward to derive ATP synthesis from ADP and phosphate and the fourth H+ is used to bring about the energy-requiring electrogenic expulsion of ATP4- in exchange for extramitochondrial ADP3-, via the H+/H2PO4- symporter. PMID:31621

Malaria Vector Control Still Matters despite Insecticide Resistance.

Science.gov (United States)

Alout, Haoues; Labbé, Pierrick; Chandre, Fabrice; Cohuet, Anna

2017-08-01

Mosquito vectors' resistance to insecticides is usually considered a major threat to the recent progresses in malaria control. However, studies measuring the impact of interventions and insecticide resistance reveal inconsistencies when using entomological versus epidemiological indices. First, evaluation tests that do not reflect the susceptibility of mosquitoes when they are infectious may underestimate insecticide efficacy. Moreover, interactions between insecticide resistance and vectorial capacity reveal nonintuitive outcomes of interventions. Therefore, considering ecological interactions between vector, parasite, and environment highlights that the impact of insecticide resistance on the malaria burden is not straightforward and we suggest that vector control still matters despite insecticide resistance. Copyright © 2017 Elsevier Ltd. All rights reserved.

El método de los elementos finitos para el modelado de ondas con un procesador vectorial

OpenAIRE

Sanz, F.; Serón, Francisco J.; Kindelan, M.; Pérez, C.

1990-01-01

El objetivo de este trabajo es analizar los aspectos computacionales del Método de los Eleinentos Finitos para la resolución de las ecuaciones de onda elásticas. Se analizan las técnicas nuinéricas necesarias desde el punto de vista de la precisión, prestaciones y necesidades de almacenamiento cuando se impleinentan en procesadores escalares y vectoriales con gran capacidad de almacenamiento. El método se ha iinplementado en un IBM 3090 con procesador vectorial usando diferentes algorit...

Sobre el estado electro-tónico y su interpretación: el potencial vectorial

Directory of Open Access Journals (Sweden)

Mauricio Rozo Clavijo

2015-10-01

Full Text Available Se presenta un análisis acerca de las perspectivas que surgieron sobre el potencial vectorial a partir de los escritos originales de Faraday y Maxwell. Se muestran las primeras ideas sobre los experimentos y las explicaciones que Faraday desarrolló en torno a la inducción magnética, y la influencia que tuvo su concepto de estado electro-tónico en la primera explicación que formuló Maxwell, quien lo definió como el estado mediante el cual se ejecutan las acciones magnéticas a través de líneas de fuerza. Señala que ese concepto es la base para explicar el fenómeno de la inducción magnética en términos no newtonianos y lo formaliza mediante la variación temporal de la circulación del potencial vectorial a lo largo de una trayectoria cerrada. Este tipo de análisis muestra la manera en que estos pensadores representan el fenómeno, la cual no se evidencia en la literatura, sino que se muestra como una formalización alrededor del campo magnético. On the Electro-Tonic State and its Interpretation: The Vector Potential An analysis is presented on the emerging perspectives about the vector potential from Faraday and Maxwell’s original writings. This paper presents the initial observations about the experiments and explanations developed by Faraday on Magnetic Induction and the influence that his concept of Electrotonic State had on Maxwell’s first explanation. He defined it as the state by which magnetic actions are executed through lines of force. He pointed out that this concept is critical to explain the phenomenon of Magnetic Induction in non-Newtonian terms. Therefore, he formalized it by the circulation of vector potential throughout a closed trajectory. This kind of analysis shows how these researchers represented the phenomenon which is not evident in literature. It’s presented as a formalization around magnetic field instead. Sobre o estado electro-tônica e sua interpretação: o potencial vetor Mostra-se uma an

Acentric 2-D ensembles of D-br-A electron-transfer chromophores via vectorial orientation within amphiphilic n-helix bundle peptides for photovoltaic device applications.

Science.gov (United States)

Koo, Jaseung; Park, Jaehong; Tronin, Andrey; Zhang, Ruili; Krishnan, Venkata; Strzalka, Joseph; Kuzmenko, Ivan; Fry, H Christopher; Therien, Michael J; Blasie, J Kent

2012-02-14

We show that simply designed amphiphilic 4-helix bundle peptides can be utilized to vectorially orient a linearly extended donor-bridge-acceptor (D-br-A) electron transfer (ET) chromophore within its core. The bundle's interior is shown to provide a unique solvation environment for the D-br-A assembly not accessible in conventional solvents and thereby control the magnitudes of both light-induced ET and thermal charge recombination rate constants. The amphiphilicity of the bundle's exterior was employed to vectorially orient the peptide-chromophore complex at a liquid-gas interface, and its ends were tailored for subsequent covalent attachment to an inorganic surface, via a "directed assembly" approach. Structural data, combined with evaluation of the excited state dynamics exhibited by these peptide-chromophore complexes, demonstrate that densely packed, acentrically ordered 2-D monolayer ensembles of such complexes at high in-plane chromophore densities approaching 1/200 Å(2) offer unique potential as active layers in binary heterojunction photovoltaic devices.

Alternative Method for the Mass Rearing of Lutzomyia (Lutzomyia) cruzi (Diptera: Psychodidae) in a Laboratory Setting.

Science.gov (United States)

Oliveira, E F; Fernandes, W S; Oshiro, E T; Oliveira, A G; Galati, E A B

2015-09-01

The understanding of the transmission dynamics of Leishmania spp. Ross as well as the epidemiology and spread of leishmaniasis is related to parasite-vector-host interactions. These interactions can be studied using specimens of a sand fly population reared in the laboratory, exposing individuals to experimental infection for the investigation of vector competence and parameters of the vectorial capacity of the species. The present study sought to describe an alternative method for the implantation of a Lutzomyia (Lutzomyia) cruzi colony with wild specimens captured in the municipality of Corumbá, Brazil. With Method 1, engorged females were individualized for oviposition. The eggs were transferred to an acrylic petri dish with a layer of plaster on the bottom, on which food was placed after hatching of the first larvae. With Method 2, females were kept in groups for oviposition in containers, in which soil and food were placed on their bottom for the larvae. In addition, the exposure time of the larvae to light was reduced in comparison with Method 1. With Method 2, a significantly greater number of specimens of Lu. cruzi was obtained. The ratio between the number of emerged adults and the females followed for oviposition was 0.42 with Method 1 and 2.75 with Method 2. The optimization of the rearing conditions for Lu. cruzi will enable the establishment of a colony providing a sufficient number of specimens to develop experimental infection by Leishmania as well as vectorial competence and some parameters of the vectorial capacity of this sand fly. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Laboratory capacity building for the International Health Regulations (IHR[2005]) in resource-poor countries: the experience of the African Field Epidemiology Network (AFENET).

Science.gov (United States)

Masanza, Monica Musenero; Nqobile, Ndlovu; Mukanga, David; Gitta, Sheba Nakacubo

2010-12-03

Laboratory is one of the core capacities that countries must develop for the implementation of the International Health Regulations (IHR[2005]) since laboratory services play a major role in all the key processes of detection, assessment, response, notification, and monitoring of events. While developed countries easily adapt their well-organized routine laboratory services, resource-limited countries need considerable capacity building as many gaps still exist. In this paper, we discuss some of the efforts made by the African Field Epidemiology Network (AFENET) in supporting laboratory capacity development in the Africa region. The efforts range from promoting graduate level training programs to building advanced technical, managerial and leadership skills to in-service short course training for peripheral laboratory staff. A number of specific projects focus on external quality assurance, basic laboratory information systems, strengthening laboratory management towards accreditation, equipment calibration, harmonization of training materials, networking and provision of pre-packaged laboratory kits to support outbreak investigation. Available evidence indicates a positive effect of these efforts on laboratory capacity in the region. However, many opportunities exist, especially to support the roll-out of these projects as well as attending to some additional critical areas such as biosafety and biosecuity. We conclude that AFENET's approach of strengthening national and sub-national systems provide a model that could be adopted in resource-limited settings such as sub-Saharan Africa.

Rickettsia Species in African Anopheles Mosquitoes

Science.gov (United States)

Socolovschi, Cristina; Pages, Frédéric; Ndiath, Mamadou O.; Ratmanov, Pavel; Raoult, Didier

2012-01-01

Background There is higher rate of R. felis infection among febrile patients than in healthy people in Sub-Saharan Africa, predominantly in the rainy season. Mosquitoes possess a high vectorial capacity and, because of their abundance and aggressiveness, likely play a role in rickettsial epidemiology. Methodology/Principal Findings Quantitative and traditional PCR assays specific for Rickettsia genes detected rickettsial DNA in 13 of 848 (1.5%) Anopheles mosquitoes collected from Côte d’Ivoire, Gabon, and Senegal. R. felis was detected in one An. gambiae molecular form S mosquito collected from Kahin, Côte d’Ivoire (1/77, 1.3%). Additionally, a new Rickettsia genotype was detected in five An. gambiae molecular form S mosquitoes collected from Côte d’Ivoire (5/77, 6.5%) and one mosquito from Libreville, Gabon (1/88, 1.1%), as well as six An. melas (6/67, 9%) mosquitoes collected from Port Gentil, Gabon. A sequence analysis of the gltA, ompB, ompA and sca4 genes indicated that this new Rickettsia sp. is closely related to R. felis. No rickettsial DNA was detected from An. funestus, An. arabiensis, or An. gambiae molecular form M mosquitoes. Additionally, a BLAST analysis of the gltA sequence from the new Rickettsia sp. resulted in a 99.71% sequence similarity to a species (JQ674485) previously detected in a blood sample of a Senegalese patient with a fever from the Bandafassi village, Kedougou region. Conclusion R. felis was detected for the first time in An. gambiae molecular form S, which represents the major African malaria vector. The discovery of R. felis, as well as a new Rickettsia species, in mosquitoes raises new issues with respect to African rickettsial epidemiology that need to be investigated, such as bacterial isolation, the degree of the vectorial capacity of mosquitoes, the animal reservoirs, and human pathogenicity. PMID:23118963

Three-dimensional orientation-unlimited polarization encryption by a single optically configured vectorial beam.

Science.gov (United States)

Li, Xiangping; Lan, Tzu-Hsiang; Tien, Chung-Hao; Gu, Min

2012-01-01

The interplay between light polarization and matter is the basis of many fundamental physical processes and applications. However, the electromagnetic wave nature of light in free space sets a fundamental limit on the three-dimensional polarization orientation of a light beam. Although a high numerical aperture objective can be used to bend the wavefront of a radially polarized beam to generate the longitudinal polarization state in the focal volume, the arbitrary three-dimensional polarization orientation of a beam has not been achieved yet. Here we present a novel technique for generating arbitrary three-dimensional polarization orientation by a single optically configured vectorial beam. As a consequence, by applying this technique to gold nanorods, orientation-unlimited polarization encryption with ultra-security is demonstrated. These results represent a new landmark of the orientation-unlimited three-dimensional polarization control of the light-matter interaction.

Mozambique field epidemiology and laboratory training program: a pathway for strengthening human resources in applied epidemiology.

Science.gov (United States)

Baltazar, Cynthia Semá; Taibo, Cátia; Sacarlal, Jahit; Gujral, Lorna; Salomão, Cristolde; Doyle, Timothy

2017-01-01

In the last decades, Mozambique has been undergoing demographic, epidemiological, economic and social transitions, which have all had a notable impact on the National Health System. New challenges have emerged, causing a need to expand the preparation and response to emerging disease threats and public health emergencies. We describe the structure and function of the Mozambique Field Epidemiology Training Program (MZ-FELTP) and the main outputs achieved during the first 6 years of program implementation (consisting of 3 cohorts). We also outline the contribution of the program to the National Health System and assess the retention of the graduates. The MZ-FELTP is a post-graduate in-service training program, based on the acquisition of skills, within two tracks: applied epidemiology and laboratory management. The program was established in 2010, with the objective of strengthening capacity in applied epidemiology and laboratory management, so that events of public health importance can be detected and investigated in a timely and effective manner. The program is in its seventh year, having successfully trained 36 health professionals in the advanced course. During the first six years of the program, more than 40 outbreaks were investigated, 37 surveillance system evaluations were conducted and 39 descriptive data analyses were performed. Surveillance activities were implemented for mass events and emergency situations. In addition, more than 100 oral and poster presentations were given by trainees at national and international conferences. The MZ-FELTP has helped provide the Ministry of Health with the human and technical resources and operational capacity, to rapidly and effectively respond to major public health challenges in the country. The continuous involvement of key stakeholders is necessary for the continuation, expansion and ongoing sustainability of the program.

Six paths for the future of social epidemiology.

Science.gov (United States)

Galea, Sandro; Link, Bruce G

2013-09-15

Social epidemiology is now an accepted part of the academic intellectual landscape. However, in many ways, social epidemiology also runs the risk of losing the identity that distinguished it as a field during its emergence. In the present article, we scan the strengths of social epidemiology to imagine paths forward that will make the field distinct and useful to the understanding of population health in future. We suggest 6 paths to such a future, each emerging from promising research trends in the field in which social epidemiologists can, and should, lead in coming years. Each of these paths contributes to the formation of distinct capacities that social epidemiologists can claim and use to elaborate or fill in gaps in the already strong history of social epidemiology. They present an opportunity for the field to build on its strengths and move forward while leading in new and critical areas in population health.

Sweet waste extract uptake by a mosquito vector: Survival, biting, fecundity responses, and potential epidemiological significance.

Science.gov (United States)

Dieng, Hamady; Satho, Tomomitsu; Abang, Fatimah; Meli, Nur Khairatun Khadijah Binti; Ghani, Idris A; Nolasco-Hipolito, Cirilo; Hakim, Hafijah; Miake, Fumio; Ahmad, Abu Hassan; Noor, Sabina; Zuharah, Wan Fatma; Ahmad, Hamdan; Majid, Abdul Hafiz A; Morales Vargas, Ronald E; Morales, Noppawan P; Attrapadung, Siriluck; Noweg, Gabriel Tonga

2017-05-01

In nature, adult mosquitoes typically utilize nectar as their main energy source, but they can switch to other as yet unidentified sugary fluids. Contemporary lifestyles, with their associated unwillingness to consume leftovers and improper disposal of waste, have resulted in the disposal of huge amounts of waste into the environment. Such refuse often contains unfinished food items, many of which contain sugar and some of which can collect water from rain and generate juices. Despite evidence that mosquitoes can feed on sugar-rich suspensions, semi-liquids, and decaying fruits, which can be abundant in garbage sites, the impacts of sweet waste fluids on dengue vectors are unknown. Here, we investigated the effects of extracts from some familiar sweet home waste items on key components of vectorial capacity of Aedes aegypti. Adult mosquitoes were fed one of five diets in this study: water (WAT); sucrose (SUG); bakery product (remnant of chocolate cake, BAK); dairy product (yogurt, YOG); and fruit (banana (BAN). Differences in survival, response time to host, and egg production were examined between groups. For both males and females, maintenance on BAK extract resulted in marked survival levels that were similar to those seen with SUG. Sweet waste extracts provided better substrates for survival compared to water, but this superiority was mostly seen with BAK. Females maintained on BAK, YOG, and BAN exhibited shorter response times to a host compared to their counterparts maintained on SUG. The levels of egg production were equivalent in waste extract- and SUG-fed females. The findings presented here illustrate the potential of sweet waste-derived fluids to contribute to the vectorial capacity of dengue vectors and suggest the necessity of readdressing the issue of waste disposal, especially that of unfinished sweet foods. Such approaches can be particularly relevant in dengue endemic areas where rainfall is frequent and waste collection infrequent. Copyright �

Adult vector control, mosquito ecology and malaria transmission.

Science.gov (United States)

Brady, Oliver J; Godfray, H Charles J; Tatem, Andrew J; Gething, Peter W; Cohen, Justin M; McKenzie, F Ellis; Alex Perkins, T; Reiner, Robert C; Tusting, Lucy S; Scott, Thomas W; Lindsay, Steven W; Hay, Simon I; Smith, David L

2015-03-01

Standard advice regarding vector control is to prefer interventions that reduce the lifespan of adult mosquitoes. The basis for this advice is a decades-old sensitivity analysis of 'vectorial capacity', a concept relevant for most malaria transmission models and based solely on adult mosquito population dynamics. Recent advances in micro-simulation models offer an opportunity to expand the theory of vectorial capacity to include both adult and juvenile mosquito stages in the model. In this study we revisit arguments about transmission and its sensitivity to mosquito bionomic parameters using an elasticity analysis of developed formulations of vectorial capacity. We show that reducing adult survival has effects on both adult and juvenile population size, which are significant for transmission and not accounted for in traditional formulations of vectorial capacity. The elasticity of these effects is dependent on various mosquito population parameters, which we explore. Overall, control is most sensitive to methods that affect adult mosquito mortality rates, followed by blood feeding frequency, human blood feeding habit, and lastly, to adult mosquito population density. These results emphasise more strongly than ever the sensitivity of transmission to adult mosquito mortality, but also suggest the high potential of combinations of interventions including larval source management. This must be done with caution, however, as policy requires a more careful consideration of costs, operational difficulties and policy goals in relation to baseline transmission. © The Author 2015. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene.

Vectorial Command of Induction Motor Pumping System Supplied by a Photovoltaic Generator

Science.gov (United States)

Makhlouf, Messaoud; Messai, Feyrouz; Benalla, Hocine

2011-01-01

With the continuous decrease of the cost of solar cells, there is an increasing interest and needs in photovoltaic (PV) system applications following standard of living improvements. Water pumping system powered by solar-cell generators are one of the most important applications. The fluctuation of solar energy on one hand, and the necessity to optimise available solar energy on the other, it is useful to develop new efficient and flexible modes to control motors that entrain the pump. A vectorial control of an asynchronous motor fed by a photovoltaic system is proposed. This paper investigates a photovoltaic-electro mechanic chain, composed of a PV generator, DC-AC converter, a vector controlled induction motor and centrifugal pump. The PV generator is forced to operate at its maximum power point by using an appropriate search algorithm integrated in the vector control. The optimization is realized without need to adding a DC-DC converter to the chain. The motor supply is also ensured in all insolation conditions. Simulation results show the effectiveness and feasibility of such an approach.

How to make epidemiological training infectious.

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Steve E Bellan

Full Text Available Modern infectious disease epidemiology builds on two independently developed fields: classical epidemiology and dynamical epidemiology. Over the past decade, integration of the two fields has increased in research practice, but training options within the fields remain distinct with few opportunities for integration in the classroom. The annual Clinic on the Meaningful Modeling of Epidemiological Data (MMED at the African Institute for Mathematical Sciences has begun to address this gap. MMED offers participants exposure to a broad range of concepts and techniques from both epidemiological traditions. During MMED 2010 we developed a pedagogical approach that bridges the traditional distinction between classical and dynamical epidemiology and can be used at multiple educational levels, from high school to graduate level courses. The approach is hands-on, consisting of a real-time simulation of a stochastic outbreak in course participants, including realistic data reporting, followed by a variety of mathematical and statistical analyses, stemming from both epidemiological traditions. During the exercise, dynamical epidemiologists developed empirical skills such as study design and learned concepts of bias while classical epidemiologists were trained in systems thinking and began to understand epidemics as dynamic nonlinear processes. We believe this type of integrated educational tool will prove extremely valuable in the training of future infectious disease epidemiologists. We also believe that such interdisciplinary training will be critical for local capacity building in analytical epidemiology as Africa continues to produce new cohorts of well-trained mathematicians, statisticians, and scientists. And because the lessons draw on skills and concepts from many fields in biology--from pathogen biology, evolutionary dynamics of host--pathogen interactions, and the ecology of infectious disease to bioinformatics, computational biology, and

Change in composition of the Anopheles gambiae complex and its possible implications for the transmission of malaria and lymphatic filariasis in north-eastern Tanzania

DEFF Research Database (Denmark)

Derua, Yahya A; Alifrangis, Michael; Hosea, Kenneth M

2012-01-01

ABSTRACT: BACKGROUND: A dramatic decline in the incidence of malaria due to Plasmodium falciparum infection in coastal East Africa has recently been reported to be paralleled (or even preceded) by an equally dramatic decline in malaria vector density, despite absence of organized vector control. ...... to differences in biology and vectorial capacity of the An. gambiae s.l. complex the change in sibling species composition will have important implications for the epidemiology and control of malaria and lymphatic filariasis in the study area.......ABSTRACT: BACKGROUND: A dramatic decline in the incidence of malaria due to Plasmodium falciparum infection in coastal East Africa has recently been reported to be paralleled (or even preceded) by an equally dramatic decline in malaria vector density, despite absence of organized vector control...

Life cycle and vectorial competence of Triatoma williami (Galvão, Souza e Lima, 1965) under the influence of different blood meal sources.

Science.gov (United States)

Lunardi, Rosaline Rocha; Gomes, Letícia Pinho; Peres Câmara, Thaís; Arrais-Silva, Wagner Welber

2015-09-01

Triatoma williami is naturally infected by Trypanosoma cruzi, the ethiological agent of Chagas disease, the most significant cause of morbidity and mortality in South and Central America.The possibility of domiciliation of T. williami increases the risk of human T. cruzi vetorial transmission. Despite this, there is a lack of data demonstrating the bionomic aspects, the vectorial competence or the natural ecotope and the wild hosts of T. williami. This study describes for the first time the life cycle of T. williami under the influence of two blood meal sources and also evaluates the vectorial potential of the species. The development of two groups of hundred triatomines was followed over the nymphal stages and adulthood. Each group was exposed to a sole blood meal source, mammalian or bird. The average egg-to-adult development time in both groups was similar, except by shorter stages of N3 and N4 in triatomines fed on mammals. The group fed on birds needed more blood feedings to suffer the ecdysis and had higher cumulative mortality in the nymphal stages. Although the observed delay at defecation of adults after feeding, our results suggest that T. williami in the third and fifth nymphal stages may be good vectors. Copyright © 2015 Elsevier B.V. All rights reserved.

Predicción de la estructura secundaria de proteínas usando Máquinas de soporte Vectorial

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Darío José Delgado

2012-01-01

Full Text Available Título en ingles: Protein secondary structure prediction    using  support vector machines Abstract : Among the computational methods used for predicting secondary structure proteins highlights the use of support vector machines. This research shows the predicted secondary structure of protein from its primary amino acid sequence using Support Vector Machines. As inputs, in the proposed methodology, features are used from different structural motifs or text strings associated with the primary structure which represents the secondary structure, such as R-group and the probability that the amino acid at position adopts a central particular secondary structure. For feature extraction method is used coding of sequences in which each symbol in the primary structure is associated with each symbol in the secondary structure. The use of this encoding method reduces the dimensionality of the data of thousands of characteristics only 220 of these. The results obtained are comparable to those reported in the literature, taking about 70% accuracy. Furthermore, it is possible to reduce computational cost in the construction of classifiers because this work models the problem of multi classification as a group of binary classifiers. Key words: coding methodology; support vector machines; prediction of protein secondary structure. Resumen: Entre los métodos computacionales utilizados para la predicción de la estructura secundaria de proteínas, se destaca el uso de máquinas de soporte vectorial. Este trabajo de investigación presenta la predicción de la estructura secundaria de proteínas desde su secuencia primaria de aminoácidos usando Máquinas de Soporte Vectorial. Como entradas, en la metodología propuesta, se utilizan características de los diferentes motivos estructurales o cadenas de texto asociadas a la estructura primaria que representa la estructura secundaria, tales como el R-grupo y la probabilidad de que el aminoácido en la posici

Three-dimensional polarization marked multiple-QR code encryption by optimizing a single vectorial beam

Science.gov (United States)

Lin, Chao; Shen, Xueju; Hua, Binbin; Wang, Zhisong

2015-10-01

We demonstrate the feasibility of three dimensional (3D) polarization multiplexing by optimizing a single vectorial beam using a multiple-signal window multiple-plane (MSW-MP) phase retrieval algorithm. Original messages represented with multiple quick response (QR) codes are first partitioned into a series of subblocks. Then, each subblock is marked with a specific polarization state and randomly distributed in 3D space with both longitudinal and transversal adjustable freedoms. A generalized 3D polarization mapping protocol is established to generate a 3D polarization key. Finally, multiple-QR code is encrypted into one phase only mask and one polarization only mask based on the modified Gerchberg-Saxton (GS) algorithm. We take the polarization mask as the cyphertext and the phase only mask as additional dimension of key. Only when both the phase key and 3D polarization key are correct, original messages can be recovered. We verify our proposal with both simulation and experiment evidences.

A Fast Alternating Minimization Algorithm for Nonlocal Vectorial Total Variational Multichannel Image Denoising

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Rubing Xi

2014-01-01

Full Text Available The variational models with nonlocal regularization offer superior image restoration quality over traditional method. But the processing speed remains a bottleneck due to the calculation quantity brought by the recent iterative algorithms. In this paper, a fast algorithm is proposed to restore the multichannel image in the presence of additive Gaussian noise by minimizing an energy function consisting of an l2-norm fidelity term and a nonlocal vectorial total variational regularization term. This algorithm is based on the variable splitting and penalty techniques in optimization. Following our previous work on the proof of the existence and the uniqueness of the solution of the model, we establish and prove the convergence properties of this algorithm, which are the finite convergence for some variables and the q-linear convergence for the rest. Experiments show that this model has a fabulous texture-preserving property in restoring color images. Both the theoretical derivation of the computation complexity analysis and the experimental results show that the proposed algorithm performs favorably in comparison to the widely used fixed point algorithm.

Modulación Vectorial de Inversores Multinivel con Diodos de Enclavamiento con Balance del Bus de Continua

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Santiago A. Verne

2009-04-01

Full Text Available Resumen: En este trabajo se presenta un algoritmo de modulación para convertidores multinivel de enclavamiento por diodos que optimiza el balance del bus de continua. Se describe el mecanismo de modulación vectorial para convertidores multinivel y se desarrolla un método que permite mantener equilibradas las tensiones del bus de continua utilizando la redundancia del convertidor. El presente algoritmo puede aplicarse a convertidores con un número arbitrario de niveles. Se consideran en el desarrollo dos situaciones prácticas: presencia o ausencia de una fuente de tensión continua sobre el bus. El desempeño del modulador es estudiado mediante simulaciones digitales. Palabras clave: convertidores multinivel, modulación, vector espacial

El método de los elementos finitos para el modelado de la ecuación de ondas con un procesador vectorial

OpenAIRE

Seron, F.; Sanz, F.; Kindelan, M.; C.Perez, C.Perez

1990-01-01

El objetivo de este trabajo es analizar los aspectos computacionales del Método de los Elementos Finitos para la resolución de las ecuaciones de onda elásticas. Se analizan las técnicas numéricas necesarias desde el punto de vista de la precisión, prestaciones y necesidades de almacenamiento cuando se implementan en procesadores escalares y vectoriales con gran capacidad de almacenamiento. El método se ha implementado en un IBM 3090 con procesador vectorial usando diferentes algoritmos para l...

[Eco-epidemiology: towards epidemiology of complexity].

Science.gov (United States)

Bizouarn, Philippe

2016-05-01

In order to solve public health problems posed by the epidemiology of risk factors centered on the individual and neglecting the causal processes linking the risk factors with the health outcomes, Mervyn Susser proposed a multilevel epidemiology called eco-epidemiology, addressing the interdependence of individuals and their connection with molecular, individual, societal, environmental levels of organization participating in the causal disease processes. The aim of this epidemiology is to integrate more than a level of organization in design, analysis and interpretation of health problems. After presenting the main criticisms of risk-factor epidemiology focused on the individual, we will try to show how eco-epidemiology and its development could help to understand the need for a broader and integrative epidemiology, in which studies designed to identify risk factors would be balanced by studies designed to answer other questions equally vital to public health. © 2016 médecine/sciences – Inserm.

Determinants of compliance with anti-vectorial protective measures among non-immune travellers during missions to tropical Africa.

Science.gov (United States)

Sagui, Emmanuel; Resseguier, Noémie; Machault, Vanessa; Ollivier, Lénaïck; Orlandi-Pradines, Eve; Texier, Gaetan; Pages, Frédéric; Michel, Remy; Pradines, Bruno; Briolant, Sébastien; Buguet, Alain; Tourette-Turgis, Catherine; Rogier, Christophe

2011-08-10

The effectiveness of anti-vectorial malaria protective measures in travellers and expatriates is hampered by incorrect compliance. The objective of the present study was to identify the determinants of compliance with anti-vectorial protective measures (AVPMs) in this population that is particularly at risk because of their lack of immunity. Compliance with wearing long clothing, sleeping under insecticide-impregnated bed nets (IIBNs) and using insect repellent was estimated and analysed by questionnaires administered to 2,205 French military travellers from 20 groups before and after short-term missions (approximately four months) in six tropical African countries (Senegal, Ivory Coast, Chad, Central African Republic, Gabon and Djibouti). For each AVPM, the association of "correct compliance" with individual and collective variables was investigated using random-effect mixed logistic regression models to take into account the clustered design of the study. The correct compliance rates were 48.6%, 50.6% and 18.5% for wearing long clothing, sleeping under bed nets and using repellents, respectively. Depending on the AVPM, correct compliance was significantly associated with the following factors: country, older than 24 years of age, management responsibilities, the perception of a personal malaria risk greater than that of other travellers, the occurrence of life events, early bedtime (i.e., before midnight), the type of stay (field operation compared to training), the absence of medical history of malaria, the absence of previous travel in malaria-endemic areas and the absence of tobacco consumption.There was no competition between compliance with the different AVPMs or between compliance with any AVPM and malaria chemoprophylaxis. Interventions aimed at improving compliance with AVPMs should target young people without management responsibilities who are scheduled for non-operational activities in countries with high risk of clinical malaria. Weak associations

Vectorial transport of bile salts across MDCK cells expressing both rat Na+-taurocholate cotransporting polypeptide and rat bile salt export pump.

Science.gov (United States)

Mita, Sachiko; Suzuki, Hiroshi; Akita, Hidetaka; Stieger, Bruno; Meier, Peter J; Hofmann, Alan F; Sugiyama, Yuichi

2005-01-01

Bile salts are predominantly taken up by hepatocytes via the basolateral Na(+)-taurocholate cotransporting polypeptide (NTCP/SLC10A1) and secreted into the bile by the bile salt export pump (BSEP/ABCB11). In the present study, we transfected rat Ntcp and rat Bsep into polarized Madin-Darby canine kidney cells and characterized the transport properties of these cells for eight bile salts. Immunohistochemical staining demonstrated that Ntcp was expressed at the basolateral domains, whereas Bsep was expressed at the apical domains. Basal-to-apical transport of taurocholate across the monolayer expressing only Ntcp and that coexpressing Ntcp/Bsep was observed, whereas the flux across the monolayer of control and Bsep-expressing cells was symmetrical. Basal-to-apical transport of taurocholate across Ntcp/Bsep-coexpressing monolayers was significantly higher than that across monolayers expressing only Ntcp. Kinetic analysis of this vectorial transport of taurocholate gave an apparent K(m) value of 13.9 +/- 4.7 microM for cells expressing Ntcp alone, which is comparable with 22.2 +/- 4.5 microM for cells expressing both Ntcp and Bsep and V(max) values of 15.8 +/- 4.2 and 60.8 +/- 9.0 pmol.min(-1).mg protein(-1) for Ntcp alone and Ntcp and Bsep-coexpressing cells, respectively. Transcellular transport of cholate, glycocholate, taurochenodeoxycholate, chenodeoxycholate, glycochenodeoxycholate, tauroursodeoxycholate, ursodeoxycholate, and glycoursodeoxycholate, but not that of lithocholate was also observed across the double transfectant. This double-expressing system can be used as a model to clarify vectorial transport of bile salts across hepatocytes under physiological conditions.

Population health and status of epidemiology: WHO European Region I.

Science.gov (United States)

Rahu, Mati; Vlassov, Vasiliy V; Pega, Frank; Andreeva, Tatiana; Ay, Pinar; Baburin, Aleksei; Bencko, Vladimír; Csépe, Péter; Gebska-Kuczerowska, Anita; Ondrusová, Martina; Ribak, Joseph

2013-06-01

This article of the International Epidemiological Association commissioned paper series stocktakes the population health and status of epidemiology in 21 of the 53 countries of the WHO European Region. By United Nations geographical classification, these countries belong to Eastern Europe, Western Asia and South-Central Asia. Published data were used to describe population health indicators and risk factors. Epidemiological training and research was assessed based on author knowledge, information searches and E-mail survey of experts. Bibliometric analyses determined epidemiological publication outputs. Between-country differences in life expectancy, amount and profile of disease burden and prevalence of risk factors are marked. Epidemiological training is affected by ongoing structural reforms of educational systems. Training is advanced in Israel and several Eastern European countries. Epidemiological research is mainly university-based in most countries, but predominantly conducted by governmental research institutes in several countries of the former Soviet Union. Funding is generally external and limited, partially due to competition from and prioritization of biomedical research. Multiple relevant professional societies exist, especially in Poland, the Czech Republic and Hungary. Few of the region's 39 epidemiological academic journals have international currency. The number of epidemiological publications per population is highest for Israel and lowest for South-Central Asian countries. Epidemiological capacity will continue to be heterogeneous across the region and depend more on countries' individual historical, social, political and economic conditions and contexts than their epidemiologists' successive efforts. National and international research funding, and within- and between-country collaborations should be enhanced, especially for South-Central Asian countries.

New Vectorial Propulsion System and Trajectory Control Designs for Improved AUV Mission Autonomy

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Ivan Masmitja

2018-04-01

Full Text Available Autonomous Underwater Vehicles (AUV are proving to be a promising platform design for multidisciplinary autonomous operability with a wide range of applications in marine ecology and geoscience. Here, two novel contributions towards increasing the autonomous navigation capability of a new AUV prototype (the Guanay II as a mix between a propelled vehicle and a glider are presented. Firstly, a vectorial propulsion system has been designed to provide full vehicle maneuverability in both horizontal and vertical planes. Furthermore, two controllers have been designed, based on fuzzy controls, to provide the vehicle with autonomous navigation capabilities. Due to the decoupled system propriety, the controllers in the horizontal plane have been designed separately from the vertical plane. This class of non-linear controllers has been used to interpret linguistic laws into different zones of functionality. This method provided good performance, used as interpolation between different rules or linear controls. Both improvements have been validated through simulations and field tests, displaying good performance results. Finally, the conclusion of this work is that the Guanay II AUV has a solid controller to perform autonomous navigation and carry out vertical immersions.

New Vectorial Propulsion System and Trajectory Control Designs for Improved AUV Mission Autonomy.

Science.gov (United States)

Masmitja, Ivan; Gonzalez, Julian; Galarza, Cesar; Gomariz, Spartacus; Aguzzi, Jacopo; Del Rio, Joaquin

2018-04-17

Autonomous Underwater Vehicles (AUV) are proving to be a promising platform design for multidisciplinary autonomous operability with a wide range of applications in marine ecology and geoscience. Here, two novel contributions towards increasing the autonomous navigation capability of a new AUV prototype (the Guanay II) as a mix between a propelled vehicle and a glider are presented. Firstly, a vectorial propulsion system has been designed to provide full vehicle maneuverability in both horizontal and vertical planes. Furthermore, two controllers have been designed, based on fuzzy controls, to provide the vehicle with autonomous navigation capabilities. Due to the decoupled system propriety, the controllers in the horizontal plane have been designed separately from the vertical plane. This class of non-linear controllers has been used to interpret linguistic laws into different zones of functionality. This method provided good performance, used as interpolation between different rules or linear controls. Both improvements have been validated through simulations and field tests, displaying good performance results. Finally, the conclusion of this work is that the Guanay II AUV has a solid controller to perform autonomous navigation and carry out vertical immersions.

Profesi Epidemiologi

Directory of Open Access Journals (Sweden)

Buchari Lapau

2011-01-01

Full Text Available Makalah ini pertama kali menjelaskan perlu adanya profesi kesehatan masyarakat dalam rangka pembangunan kesehatan. Lalu dijelaskan apa profesi itu dan standar keberadaan profesi, atas dasar mana dapat ditetapkan bahwa pelayanan epidemiologi merupakan salah satu profesi. Dalam rangka pembinaan profesi kesehatan masyarakat, IAKMI dan APTKMI telah membentuk Majelis Kolegium Kesehatan Masyarakat Indonesia (MKKMI yang terdiri atas 8 kolegium antara lain Kolegium Epidemiologi, yang telah menyusun Standar Profesi Epidemiologi yang terdiri atas beberapa standar. Masing-masing standar dijelaskan mulai dari kurikulum, standar pelayanan epidmiologi, profil epidemiolog kesehatan, peran epidemiolog kesehatan, fungsi epidemiolog kesehatan, standar kompetensi epidemiologi, dan standar pendidikan profesi epidemiologi.

General imaging of advanced 3D mask objects based on the fully-vectorial extended Nijboer-Zernike (ENZ) theory

Science.gov (United States)

van Haver, Sven; Janssen, Olaf T. A.; Braat, Joseph J. M.; Janssen, Augustus J. E. M.; Urbach, H. Paul; Pereira, Silvania F.

2008-03-01

In this paper we introduce a new mask imaging algorithm that is based on the source point integration method (or Abbe method). The method presented here distinguishes itself from existing methods by exploiting the through-focus imaging feature of the Extended Nijboer-Zernike (ENZ) theory of diffraction. An introduction to ENZ-theory and its application in general imaging is provided after which we describe the mask imaging scheme that can be derived from it. The remainder of the paper is devoted to illustrating the advantages of the new method over existing methods (Hopkins-based). To this extent several simulation results are included that illustrate advantages arising from: the accurate incorporation of isolated structures, the rigorous treatment of the object (mask topography) and the fully vectorial through-focus image formation of the ENZ-based algorithm.

Current status and future prospects of epidemiology and public health training and research in the WHO African region

Science.gov (United States)

Nachega, Jean B; Uthman, Olalekan A; Ho, Yuh-Shan; Lo, Melanie; Anude, Chuka; Kayembe, Patrick; Wabwire-Mangen, Fred; Gomo, Exnevia; Sow, Papa Salif; Obike, Ude; Kusiaku, Theophile; Mills, Edward J; Mayosi, Bongani M; IJsselmuiden, Carel

2012-01-01

Background To date little has been published about epidemiology and public health capacity (training, research, funding, human resources) in WHO/AFRO to help guide future planning by various stakeholders. Methods A bibliometric analysis was performed to identify published epidemiological research. Information about epidemiology and public health training, current research and challenges was collected from key informants using a standardized questionnaire. Results From 1991 to 2010, epidemiology and public health research output in the WHO/AFRO region increased from 172 to 1086 peer-reviewed articles per annum [annual percentage change (APC) = 10.1%, P for trend Africa increased during the same period. However, an overwhelming majority of respondents (>90%) reported that this increase is only rarely linked to regional post-graduate training programmes in epidemiology. South Africa leads in publications (1978/8835, 22.4%), followed by Kenya (851/8835, 9.6%), Nigeria (758/8835, 8.6%), Tanzania (549/8835, 6.2%) and Uganda (428/8835, 4.8%) (P Africa). Independent predictors of relevant research productivity were ‘in-country numbers of epidemiology or public health programmes’ [incidence rate ratio (IRR) = 3.41; 95% confidence interval (CI) 1.90–6.11; P = 0.03] and ‘number of HIV/AIDS patients’ (IRR = 1.30; 95% CI 1.02–1.66; P < 0.001). Conclusions Since 1991, there has been increasing epidemiological research productivity in WHO/AFRO that is associated with the number of epidemiology programmes and burden of HIV/AIDS cases. More capacity building and training initiatives in epidemiology are required to promote research and address the public health challenges facing the continent. PMID:23283719

Determinants of compliance with anti-vectorial protective measures among non-immune travellers during missions to tropical Africa

Directory of Open Access Journals (Sweden)

Briolant Sébastien

2011-08-01

Full Text Available Abstract Background The effectiveness of anti-vectorial malaria protective measures in travellers and expatriates is hampered by incorrect compliance. The objective of the present study was to identify the determinants of compliance with anti-vectorial protective measures (AVPMs in this population that is particularly at risk because of their lack of immunity. Methods Compliance with wearing long clothing, sleeping under insecticide-impregnated bed nets (IIBNs and using insect repellent was estimated and analysed by questionnaires administered to 2,205 French military travellers from 20 groups before and after short-term missions (approximately four months in six tropical African countries (Senegal, Ivory Coast, Chad, Central African Republic, Gabon and Djibouti. For each AVPM, the association of "correct compliance" with individual and collective variables was investigated using random-effect mixed logistic regression models to take into account the clustered design of the study. Results The correct compliance rates were 48.6%, 50.6% and 18.5% for wearing long clothing, sleeping under bed nets and using repellents, respectively. Depending on the AVPM, correct compliance was significantly associated with the following factors: country, older than 24 years of age, management responsibilities, the perception of a personal malaria risk greater than that of other travellers, the occurrence of life events, early bedtime (i.e., before midnight, the type of stay (field operation compared to training, the absence of medical history of malaria, the absence of previous travel in malaria-endemic areas and the absence of tobacco consumption. There was no competition between compliance with the different AVPMs or between compliance with any AVPM and malaria chemoprophylaxis. Conclusion Interventions aimed at improving compliance with AVPMs should target young people without management responsibilities who are scheduled for non-operational activities in

Factors involved in the paradox of reverse epidemiology.

Science.gov (United States)

Martín-Ponce, Esther; Santolaria, Francisco; Alemán-Valls, María-Remedios; González-Reimers, Emilio; Martínez-Riera, Antonio; Rodríguez-Gaspar, Melchor; Rodríguez-Rodríguez, Eva

2010-08-01

The hypothesis of reverse epidemiology holds that some cardiovascular risk factors, such as obesity, hypercholesterolemia and hypertension, in the elderly or in some chronic diseases are not harmful but permit better survival. However, this phenomenon is controversial and the underlying reasons are poorly understood. To search for factors simultaneously linked to reverse epidemiology and to short or long term survival. We included 400 patients, older than 60 years, hospitalized in a general internal medicine unit; 61 died in hospital and 338 were followed up by telephone. Obesity, higher blood pressure and serum cholesterol, besides being related to lower mortality both in hospital and after discharge, were associated with better nutrition and functional capacity, less intense acute phase reaction and organ dysfunction, and lower incidence of high-mortality diseases such as dementia, pneumonia, sepsis or cancer. These associations may explain why obesity and other reverse epidemiology data are inversely related to mortality. Weight loss was related to mortality independently of BMI. Patients with BMI under 30 kg/m(2) who died in hospital showed more weight loss than those who survived; the lower the BMI, the greater the weight loss. In contrast, patients with BMI over 30 kg/m(2) who died in hospital gained more weight than those who survived; the higher the BMI, the greater the weight gain. In patients over 60 years of age admitted to an internal medicine ward, obesity did not show independent survival value, being displaced by other nutritional parameters, functional capacity, acute phase reaction, organ dysfunction and diseases with poor prognosis. Copyright 2009 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

There and back again: putting the vectorial movement planning hypothesis to a critical test.

Science.gov (United States)

Kobak, Eva-Maria; Cardoso de Oliveira, Simone

2014-01-01

Based on psychophysical evidence about how learning of visuomotor transformation generalizes, it has been suggested that movements are planned on the basis of movement direction and magnitude, i.e., the vector connecting movement origin and targets. This notion is also known under the term "vectorial planning hypothesis". Previous psychophysical studies, however, have included separate areas of the workspace for training movements and testing the learning. This study eliminates this confounding factor by investigating the transfer of learning from forward to backward movements in a center-out-and-back task, in which the workspace for both movements is completely identical. Visual feedback allowed for learning only during movements towards the target (forward movements) and not while moving back to the origin (backward movements). When subjects learned the visuomotor rotation in forward movements, initial directional errors in backward movements also decreased to some degree. This learning effect in backward movements occurred predominantly when backward movements featured the same movement directions as the ones trained in forward movements (i.e., when opposite targets were presented). This suggests that learning was transferred in a direction specific way, supporting the notion that movement direction is the most prominent parameter used for motor planning.

Estrategia para determinar la línea base en áreas de interrupción vectorial de la enfermedad de Chagas

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Diego Montenegro

Full Text Available RESUMEN Objetivos Presentar una estrategia para determinar la línea de base en áreas endémicas en el proceso de interrupción vectorial de la enfermedad de Chagas (ECh. Métodos Con un cuestionario socioambiental y una encuesta entomológica, se evaluaron las condiciones físicas de los domicilios, el conocimiento de los habitantes sobre la ECh, los indicadores entomológicos de triatominos y la relación estadística entre estas variables. Resultados Existe colonización e infección natural con Trypanosoma cruzi en Rhodnius prolixus, el principal vector de la ECh en Colombia. La colonización estuvo relacionada con casas de techos de hojas de palma y paredes de adobe o bahareque. Se encontró el vector Panstrongylus geniculatus con hábitos de colonización. Casi 50% de la población encuestada asociaba el término ECh con una enfermedad humana y 37%, con los triatominos. Conclusiones R. prolixus puede considerarse el principal vector de T. cruzi en ambientes domésticos y el proceso de interrupción vectorial es factible dentro del municipio priorizado. Se necesitan nuevos estudios que comprueben la existencia de poblaciones silvestres de R. prolixus que puedan afectar las etapas futuras del proceso y demostrar si hay una participación de P. geniculatus en la dinámica de transmisión de T. cruzi. Los anteriores escenarios pueden ser viabilizados con la inclusión de los habitantes en todo el proceso, ya que han sido altamente sensibles en la detección de vectores dentro de sus casas. El diseño del estudio aquí presentado puede ser adaptado en otras áreas endémicas de la Región de las Américas.

Epidemiología de campo y epidemiología social Field epidemiology and social epidemiology

Directory of Open Access Journals (Sweden)

Javier Segura del Pozo

2006-03-01

Full Text Available Mediante la comparación de la epidemiología de campo y la epidemiología social, se pretende reflexionar sobre los imaginarios no explícitos que operan en ambos ámbitos, necesariamente convergentes, sobre los obstáculos de la práctica epidemiológica actual para alcanzar su función social y sobre la necesidad de cambiar las bases epistemológicas, metodológicas y prácticas que operan en la epidemiología, empezando por la formación del epidemiólogo de campo. La epidemiología de campo tiende a la acción sin marco teórico. La epidemiología social, por el contrario, tiende a los desarrollos teóricos (reflexión e investigación sobre los determinantes sociales alejados de la acción, debido a los limitantes para cambiar las políticas públicas. Otras diferencias se sitúan en el nivel de intervención (micro/macroespacios, el objeto de intervención (control del brote frente a control de las desigualdades y en la forma de articular la comunicación con la sociedad. Se asemejan en la preocupación por el método, la predominancia de una orientación positivista y condicionada por la estadística, aunque en proceso de cierta apertura epistemológica, la tensión experimentada entre relacionarse con un mundo virtual de bases de datos o con la sociedad real, su situación en la periferia del sistema político-social-institucional-profesional y por estar abocadas a la frustración profesional. Finalmente, se formulan 10 interrogantes a los epidemiólogos de campo sobre su práctica actual, a través de los cuales se podría evaluar si están realizando una epidemiología social, y se sugieren cambios para introducir en la formación y práctica del epidemiólogo.Comparing field epidemiology and social epidemiology, we pretend to think about the no explicit images and meanings operating in both necessary convergent fields, about the obstacles present in epidemiological practice to fulfil its social function and about the necessity of

On the solution of a vectorial radiative transfer equation in an arbitrary three-dimensional turbid medium with anisotropic scattering

International Nuclear Information System (INIS)

Budak, Vladimir P.; Korkin, Sergey V.

2008-01-01

The authors developed a numerical method of the boundary-value problem solution in the vectorial radiative transfer theory applicable to the turbid media with an arbitrary three-dimensional geometry. The method is based on the solution representation as the sum of an anisotropic part that contains all the singularities of the exact solution and a smooth regular part. The regular part of the solution could be found numerically by the finite element method that enables to extend the approach to the arbitrary medium geometry. The anisotropic part of the solution is determined analytically by the special form of the small-angle approximation. The method development is performed by the examples of the boundary-value problems for the plane unidirectional and point isotropic sources in a turbid medium slab

Surface Immobilized His-tagged Azurin as a Model Interface for the Investigation of Vectorial Electron Transfer in Biological Systems

International Nuclear Information System (INIS)

Casalini, Stefano; Berto, Marcello; Kovtun, Alessandro; Operamolla, Alessandra; Di Rocco, Giulia; Facci, Paolo; Liscio, Andrea; Farinola, Gianluca M.; Borsari, Marco; Bortolotti, Carlo A.

2015-01-01

A model system for the electrochemical investigation of vectorial electron transfer in biological systems was designed, assembled and characterized. Gold electrodes, functionalized with a -OCH_3 terminated, aromatic self-assembled monolayer, were used as a substrate for the adsorption of variants of copper-containing, redox metalloprotein azurin. The engineered azurin bears a polyhistidine tag at its C-terminus. Thanks to the presence of the solvent exposed tag, which chelates Cu"2"+ ions in solution, we introduced an exogenous redox centre. The different reduction potentials of the two redox centres and their positioning with respect to the surface are such that electron transfer from the exogenous copper centre and the electrode is mediated by the native azurin active site, closely paralleling electron transfer processes in naturally occurring multicentre metalloproteins.

Spatial variability in the density, distribution and vectorial capacity of ...

African Journals Online (AJOL)

Malaria transmission varies from one area to another and there are also local difference in time and space. The objective of the study was to determine the local variability of entomological parameters namely, mosquito abundance, human biting rate (HBR), sporozoite rate for Plasmodium falciparum and entomological ...

Epidemiology in Latin America and the Caribbean: current situation and challenges.

Science.gov (United States)

Barreto, Sandhi M; Miranda, Jaime J; Figueroa, J Peter; Schmidt, Maria Inês; Munoz, Sergio; Kuri-Morales, P Pablo; Silva, Jarbas B

2012-04-01

This article analyses the epidemiological research developments in Latin America and the Caribbean (LAC). It integrates the series commissioned by the International Epidemiological Association to all WHO Regions to identify global opportunities to promote the development of epidemiology. Health situations of the regions were analysed based on published data on selected mortality, morbidity and risk factors. Epidemiological publication output by country was estimated by Medline bibliometrics. Internet and literature searches and data provided by key informants were used to describe perspectives on epidemiological training, research and funding. Despite important advances in recent decades, LAC remains the world's most unequal region. In 2010, 10% of the LAC's people still lived in conditions of multidimensional poverty, with huge variation among countries. The region has experienced fast and complex epidemiological changes in past decades, combining increasing rates of non-communicable diseases and injuries, and keeping uncontrolled many existing endemic and emerging diseases. Overall, epidemiological publications per year increased from 160 articles between 1961 and 1970 to 2492 between 2001 and 2010. The increase in papers per million inhabitants in the past three decades varied from 57% in Panama to 1339% in Paraguay. Universities are the main epidemiological training providers. There are at least 34 universities and other institutions in the region that offer postgraduate programmes at the master's and doctoral levels in epidemiology or public health. Most LAC countries rely largely on external funding and donors to initiate and sustain long-term research efforts. Despite the limited resources, the critical mass of LAC researchers has produced significant scientific contributions. FUTURE NEEDS: The health research panorama of the region shows enormous regional discrepancies, but great prospects. Improving research and human resources capacity in the region will

Linealización de sistemas VSC-HVDC para el diseño de un controlador PI vectorial

Directory of Open Access Journals (Sweden)

Nelson Díaz Aldana

2014-01-01

Full Text Available Los sistemas VSC-HVDC son muy utilizados para la transmisión de energía en redes de interconexión eléctrica. Uno de los principales problemas que poseen estos sistemas es la complejidad de su modelo matemático, lo que conlleva grandes dificultades para el diseño de controladores que permitan la regulación de parámetros como la tensión DC de transmisión, así como la potencia activa y reactiva del sistema VSC-HVDC. En este artículo se presenta la linealización de un sistema VSC-HVDC y el posterior diseño de un controlador lineal PI vectorial a partir del modelo linealizado. Adicionalmente, se proponen dos estrategias para la validación de este tipo de controladores, la primera consiste en un único controlador PI para regular los estados del sistema para cada VSC, la segunda consiste en el diseño de controladores PI vectoriales independientes para la regulación de cada estado del VSC.

Creation of a longitudinally polarized subwavelength hotspot with an ultra-thin planar lens: vectorial Rayleigh–Sommerfeld method

International Nuclear Information System (INIS)

Ye, Huapeng; Qiu, Cheng-Wei; Huang, Kun; Yeo, Swee Ping; Teng, Jinghua; Luk’yanchuk, Boris

2013-01-01

This letter shows how a longitudinally polarized hotspot can be created by a planar ultra-thin lens that beats the diffraction limit. On the imaging plane, a subwavelength optical resolution 0.39λ with almost purely longitudinal electric component has been demonstrated in air ambient. This novel paradigm addresses simultaneously both longitudinal polarization and deep sub-diffraction imaging, by a planar lens composed of ultra-thin opaque concentric annuli. The vectorial Rayleigh–Sommerfeld (VRS) approach, offering the advantage of significant reduction in computation, has been developed for a particular optimization of a flat lens with full control of polarization. Empowered by the robustness of VRS in dealing with polarization states, the proposed roadmap may be universally and efficiently integrated with other optimization algorithms to design super-resolution imaging with controlled polarization states at any wavelength without luminescence of the object. The lens, which is empowered by the proposed method, opens an avenue for the first time toward a highly integrated imaging system with advanced functionalities in far-field super-imaging, tailored polarization states and flat ultra-thin geometry simultaneously. (letter)

Vectorial loading of processive motor proteins: implementing a landscape picture

International Nuclear Information System (INIS)

Kim, Young C; Fisher, Michael E

2005-01-01

Individual processive molecular motors, of which conventional kinesin is the most studied quantitatively, move along polar molecular tracks and, by exerting a force F = (F x ,F y ,F z ) on a tether, drag cellular cargoes, in vivo, or spherical beads, in vitro, taking up to hundreds of nanometre-scale steps. From observations of velocities and the dispersion of displacements with time, under measured forces and controlled fuel supply (typically ATP), one may hope to obtain insight into the molecular motions undergone in the individual steps. In the simplest situation, the load force F may be regarded as a scalar resisting force, F x z >0, while more recently Block and co-workers (2002 Biophys. J. 83 491, 2003 Proc. Natl Acad. Sci. USA 100 2351) and Carter and Cross (2005 Nature 435 308) have studied assisting (or reverse) loads, F x >0, and also sideways (or transverse) loads F y ≠ 0. We extend previous mechanochemical kinetic models by explicitly implementing a free-energy landscape picture in order to allow for the full vectorial nature of the force F transmitted by the tether. The load-dependence of the various forward and reverse transition rates is embodied in load distribution vectors, θ j + and θ j - , which relate to substeps of the motor, and in next order, in compliance matrices η j + and η j - . The approach is applied specifically to discuss the experiments of Howard and co-workers (1996 Biophys.?J. 70 418) in which the buckling of partially clamped microtubules was measured under the action of bound kinesin molecules which induced determined perpendicular loads. But in the normal single-bead assay it also proves imperative to allow for F z >0: the appropriate analysis for kinesin, suggesting that the motor 'crouches' on binding ATP prior to stepping, is sketched. It yields an expression for the velocity, V (F x ,F z ;[ATP]), needed to address the buckling experiments

Sequence analysis of mitochondrial 16S ribosomal RNA gene ...

Indian Academy of Sciences (India)

Unknown

For the understanding of their vectorial capacity, identification of disease carrying and refractory strains is essential. ... been widely used for phylogenetic studies and sequence differences in ... In order to fill up the internal gap, a new set.

HIV-1 and HIV-2 infections in Guinea-Bissau, West Africa : studies of immune responses, prevailing viruses and epidemiological trends

OpenAIRE

Andersson, Sören

1999-01-01

This thesis encompasses immunological, virological and epidemiological studies of HIV-1 and HIV-2 infections in Guinea-Bissau. We have established a robust and reliable diagnostic strategy based on a combination of enzyme-linked immunosorbent assays (ELISAs) and rapid simple tests. Evaluations showed that the strategy had a high capacity to discriminate between HIV-1 and HIV-2 and a high concordance with polymerase chain reaction (PCR) testing. Epidemiological studies in...

Increasing chronic disease research capacity in Guatemala through a mentoring program.

Science.gov (United States)

Barnoya, Joaquin; Monzon, Jose C; Colditz, Graham A

2013-09-12

The Chronic Disease Research Fellowship Program (RFP) aims to build the research capacity of recent medical graduates to support the development of chronic disease control strategies. Guatemala is undergoing an epidemiologic transition. However, given the way universities and the health care system are structured, it lacks an environment that fosters research careers and generates the required knowledge to implement sound public health policies and clinical strategies. The RFP was implemented at the Cardiovascular Unit of Guatemala. This 4-year Program recruited two one-year fellows and provided funding to define a research topic, write a protocol and implement the research. Strong emphasis is placed on developing skills in knowledge translation and exchange to bridge the "know-do" gap. Close mentoring relationships between the Principal Investigator and former and current fellows are fostered through the Program. The mentoring Program has generated strategic data to support the implementation of sound chronic disease control strategies, mainly related to tobacco control. Results have been presented nationally and internationally. Research training has included principles of biostatistics and epidemiology, and a journal club. The Program is increasingly generating interest among medical graduates to pursue further research training abroad and is building local research capacity. Fellows and research assistants have created a research network in Guatemala and abroad. The main obstacle the Program faces is ensuring long-term sustainability. A mentoring program can lead to an increase in research interest and capacity in a low-income country with little research infrastructure.

Vectorial acylation in Saccharomyces cerevisiae. Fat1p and fatty acyl-CoA synthetase are interacting components of a fatty acid import complex

DEFF Research Database (Denmark)

Zou, Zhiying; Tong, Fumin; Færgeman, Nils J.

2003-01-01

the growth defect in the faa1Delta fat1Delta strain indicating some essential functions of Fat1p cannot be performed by Faa4p. Chromosomally encoded FAA1 and FAT1 are not able to suppress the growth deficiencies of the fat1Delta faa1Delta and faa1Delta faa4Delta strains, respectively, indicating Faa1p...... as trap were active when tested using the yeast two-hybrid system. Third, co-expressed, differentially tagged Fat1p and Faa1p or Faa4p were co-immunoprecipitated. Collectively, these data support the hypothesis that fatty acid import by vectorial acylation in yeast requires a multiprotein complex, which...... consists of Fat1p and Faa1p or Faa4p....

2018-02-24T00:03:51Z https://www.ajol.info/index.php/all/oai oai:ojs ...

African Journals Online (AJOL)

article/71991 2018-02-24T00:03:51Z thrb:ART Malaria entomological profile in Tanzania from 1950 to 2010: a review of mosquito distribution, vectorial capacity and insecticide resistance Kabula, Bilali; Tukuyu Medical Research Centre, Tukuyu ...

Recent advances in phlebotomine sand fly research related to leishmaniasis control.

Science.gov (United States)

Bates, Paul A; Depaquit, Jerôme; Galati, Eunice A B; Kamhawi, Shaden; Maroli, Michele; McDowell, Mary Ann; Picado, Albert; Ready, Paul D; Salomón, O Daniel; Shaw, Jeffrey J; Traub-Csekö, Yara M; Warburg, Alon

2015-02-27

Phlebotomine sand flies are the subject of much research because of the role of their females as the only proven natural vectors of Leishmania species, the parasitic protozoans that are the causative agents of the neglected tropical disease leishmaniasis. Activity in this field was highlighted by the eighth International Symposium on Phlebotomine Sand flies (ISOPS) held in September 2014, which prompted this review focusing on vector control. Topics reviewed include: Taxonomy and phylogenetics, Vector competence, Genetics, genomics and transcriptomics, Eco-epidemiology, and Vector control. Research on sand flies as leishmaniasis vectors has revealed a diverse array of zoonotic and anthroponotic transmission cycles, mostly in subtropical and tropical regions of Africa, Asia and Latin America, but also in Mediterranean Europe. The challenge is to progress beyond descriptive eco-epidemiology, in order to separate vectors of biomedical importance from the sand fly species that are competent vectors but lack the vectorial capacity to cause much human disease. Transmission modelling is required to identify the vectors that are a public health priority, the ones that must be controlled as part of the integrated control of leishmaniasis. Effective modelling of transmission will require the use of entomological indices more precise than those usually reported in the leishmaniasis literature.

On the optimal production capacity for influenza vaccine.

Science.gov (United States)

Forslid, Rikard; Herzing, Mathias

2015-06-01

This paper analyzes the profit maximizing capacity choice of a monopolistic vaccine producer facing the uncertain event of a pandemic in a homogenous population of forward-looking individuals. For any capacity level, the monopolist solves the intertemporal price discrimination problem within the dynamic setting generated by the standard mathematical epidemiological model of infectious diseases. Even though consumers are assumed to be identical, the monopolist will be able to exploit the ex post heterogeneity between infected and susceptible individuals by raising the price of vaccine in response to the increasing hazard rate. The monopolist thus bases its investment decision on the expected profits from the optimal price path given the infection dynamics. It is shown that the monopolist will always choose to invest in a lower production capacity than the social planner. Through numerical simulation, it is demonstrated how the loss to society of having a monopoly producer decreases with the speed of infection transmission. Moreover, it is illustrated how the monopolist's optimal vaccination rate increases as its discount rate rises for cost parameters based on Swedish data. However, the effect of the firm discount rate on its investment decision is sensitive to assumptions regarding the cost of production capacity. Copyright © 2014 John Wiley & Sons, Ltd.

Vectorial control of nonlinear emission via chiral butterfly nanoantennas: generation of pure high order nonlinear vortex beams.

Science.gov (United States)

Lesina, Antonino Cala'; Berini, Pierre; Ramunno, Lora

2017-02-06

We report on a chiral gap-nanostructure, which we term a "butterfly nanoantenna," that offers full vectorial control over nonlinear emission. The field enhancement in its gap occurs for only one circular polarization but for every incident linear polarization. As the polarization, phase and amplitude of the linear field in the gap are highly controlled, the linear field can drive nonlinear emitters within the gap, which behave as an idealized Huygens source. A general framework is thereby proposed wherein the butterfly nanoantennas can be arranged in a metasurface, and the nonlinear Huygens sources exploited to produce a highly structured far-field optical beam. Nonlinearity allows us to shape the light at shorter wavelengths, not accessible by linear plasmonics, and resulting in high purity beams. The chirality of the butterfly allows us to create orbital angular momentum states using a linearly polarized excitation. A third harmonic Laguerre-Gauss beam carrying an optical orbital angular momentum of 41 is demonstrated as an example, through large-scale simulations on a high-performance computing platform of the full plasmonic metasurface with an area large enough to contain up to 3600 nanoantennas.

Early warnings of the potential for malaria transmission in Rural Africa using the Hydrology, Entomology and Malaria Transmission Simulator (HYDREMATS)

Science.gov (United States)

Yamana, T. K.; Eltahir, E. A.

2010-12-01

Early warnings of malaria transmission allow health officials to better prepare for future epidemics. Monitoring rainfall is recognized as an important part of malaria early warning systems, as outlined by the Roll Back Malaria Initiative. The Hydrology, Entomology and Malaria Simulator (HYDREMATS) is a mechanistic model that relates rainfall to malaria transmission, and could be used to provide early warnings of malaria epidemics. HYDREMATS is used to make predictions of mosquito populations and vectorial capacity for 2005, 2006, and 2007 in Banizoumbou village in western Niger. HYDREMATS is forced by observed rainfall, followed by a rainfall prediction based on the seasonal mean rainfall for a period two or four weeks into the future. Predictions made using this method provided reasonable estimates of mosquito populations and vectorial capacity, two to four weeks in advance. The predictions were significantly improved compared to those made when HYDREMATS was forced with seasonal mean rainfall alone.

Evaluation of epidemiological studies

International Nuclear Information System (INIS)

Breckow, J.

1995-01-01

The publication is intended for readers with a professional background in radiation protection who are not experts in the field of epidemiology. The potentials and the limits of epidemiology are shown and concepts and terminology of radioepidemilogic studies as well as epidemiology in general are explained, in order to provide the necessary basis for understanding or performing evaluations of epidemiologic studies. (orig./VHE) [de

Sequence analysis of mitochondrial 16S ribosomal RNA gene

Indian Academy of Sciences (India)

Mosquitoes are vectors for the transmission of many human pathogens that include viruses, nematodes and protozoa. For the understanding of their vectorial capacity, identification of disease carrying and refractory strains is essential. Recently, molecular taxonomic techniques have been utilized for this purpose. Sequence ...

Aspectos destacados de las teorías cognitivas del aprendizaje, como estrategias didácticas para la enseñanza y aprendizaje de conceptos del cálculo vectorial

OpenAIRE

Costa, Viviana

2013-01-01

Este trabajo se centra en la problemática de la enseñanza y aprendizaje del Cálculo Vectorial. Se sitúa esta rama de la matemática en el contexto de la ingeniería y sus orígenes. Se exponen aspectos destacados de algunas teorías cognitivas del aprendizaje: la teoría de los modelos mentales de Johnson-Laird y la teoría del aprendizaje significativo subversivo. Proponemos considerar las mismas como marco referencial en el desarrollo de estrategias didácticas para la enseñanza y aprendizaje de l...

The retained capacity of Lutzomya longipalpis (Lutz & Neiva to transmit Leishmania chagasi (Cunha & Chagas after eight years (64 generations in a closed laboratory colony

Directory of Open Access Journals (Sweden)

M. de N. A. Gonçalves

1985-09-01

Full Text Available A closed Lutzomyia longipalpis colony, from Ceará has been used to transmit Leishmania chagasi isolated from a fox in Pará state. The last time this colony was successfully used in similar transmission experiments was eight years (64 generations ago indicating that this colony of Lu. longipalpis has fully maintained its vectorial capacity in spite of such a long period of maintainance in the laboratory.Lutzomyia longipalpis foi alimentado através de membrana com uma suspensão de macerado de fígado e baço em sangue desfibrinado de coelho. Este material foi originário de um hamster infectado com Leishmania chagasi, realimentado em hamsters limpos, transmitindo os parasitos em duas ocasiões. Esta mesma colônia de Lu. longipalpis, do Ceará, foi usada para a primeira transmissão há oito anos e 64 gerações atrás e não teve a capacidade vetorial diminuída.

Low dose epidemiology

International Nuclear Information System (INIS)

Tirmarche, M.; Hubert, P.

1992-01-01

Actually, epidemiological studies have to establish if the assessment of cancer risk can be verified at low chronic radiation doses. The population surveillance must be very long, the side effects and cancers of such radiation appearing much later. In France, this epidemiological study on nuclear workers have been decided recently. Before describing the experiment and french projects in epidemiology of nuclear workers, the authors present the main english and american studies

Vectorial transport of unconjugated and conjugated bile salts by monolayers of LLC-PK1 cells doubly transfected with human NTCP and BSEP or with rat Ntcp and Bsep.

Science.gov (United States)

Mita, Sachiko; Suzuki, Hiroshi; Akita, Hidetaka; Hayashi, Hisamitsu; Onuki, Reiko; Hofmann, Alan F; Sugiyama, Yuichi

2006-03-01

Na(+)-taurocholate-cotransporting peptide (NTCP)/SLC10A1 and bile salt export pump (BSEP)/ABCB11 synergistically play an important role in the transport of bile salts by the hepatocyte. In this study, we transfected human NTCP and BSEP or rat Ntcp and Bsep into LLC-PK1 cells, a cell line devoid of bile salts transporters. Transport by these cells was characterized with a focus on substrate specificity between rats and humans. The basal to apical flux of taurocholate across NTCP- and BSEP-expressing LLC-PK1 monolayers was 10 times higher than that in the opposite direction, whereas the flux across the monolayer of control and NTCP or BSEP single-expressing cells did not show any vectorial transport. The basal to apical flux of taurocholate was saturated with a K(m) value of 20 microM. Vectorial transcellular transport was also observed for cholate, chenodeoxycholate, ursodeoxycholate, their taurine and glycine conjugates, and taurodeoxycholate and glycodeoxycholate, whereas no transport of lithocholate was detected. To evaluate the respective functions of NTCP and BSEP and to compare them with those of rat Ntcp and Bsep, we calculated the clearance by each transporter in this system. A good correlation in the clearance of the examined bile salts (cholate, chenodeoxycholate, ursodeoxycholate, and their taurine or glycine conjugates) was observed between transport by human and that of rat transporters in terms of their rank order: for NTCP, taurine conjugates > glycine conjugates > unconjugated bile salts, and for BSEP, unconjugated bile salts and glycine conjugates > taurine conjugates. In conclusion, the substrate specificity of human and rat NTCP and BSEP appear to be very similar at least for monovalent bile salts under physiological conditions.

Ukraine’s Multi-Vectorial Foreign Policy: Looking West while not Overlooking its Eastern Neighbour

Directory of Open Access Journals (Sweden)

María Raquel Freire

2009-05-01

Full Text Available La Ucrania post-soviética ha perseguido un curso independiente en su política exterior desde que lograse la independencia en 1991. Sin embargo su posición geográfica condicionó mucho el contorno de su política exterior. De hecho, mientras que un acercamiento al Oeste ha sido valorado grandemente, las relaciones con Rusia han seguido siendo el pilar central de Ucrania, intentándose por tanto, mirar hacia el Oeste sin perder de vista a su vecino oriental. En tal contexto, ¿cómo podrían conciliar las autoridades ucranianas los diferentes vectores de la política exterior de su país?¿En qué medida podrían pervivir los principios de la Revolución Naranja entre un contexto interior tan difícil y un contexto exterior complejo?¿En qué medida pueden afectar a las opciones en política exterior de Kiev la influencia occidental y las interferencias rusas? Intentando encontrar respuestas a tales preguntas, este artículo tiene como objetivo la deconstrucción de los varios círculos en la política exterior multi-vectorial de Kiev que se encargan de atender a la política exterior de una manera integrada y donde las formulaciones interiores se ven condicionadas por las opciones externas, echando luz de esta manera sobre cómo las interrelaciones e interconexiones se desarrollan en el proceso de toma de decisiones y en el curso elegido.

Thickness and angular dependent magnetic anisotropy of La0.67Sr0.33MnO3 thin films by Vectorial Magneto Optical Kerr Magnetometry

Science.gov (United States)

Chaluvadi, S. K.; Perna, P.; Ajejas, F.; Camarero, J.; Pautrat, A.; Flament, S.; Méchin, L.

2017-10-01

We investigate the in-plane magnetic anisotropy in La0.67Sr0.33MnO3 thin films grown on SrTiO3 (001) substrate using angular dependent room temperature Vectorial Magneto-Optical Kerr Magnetometry. The experimental data reveals that the magnetic anisotropy symmetry landscape significantly changes depending upon the strain and thickness. At low film thickness (12 and 25 nm) the dominant uniaxial anisotropy is due to interface effects, step edges due to mis-cut angle of SrTiO3 substrate. At intermediate thickness, the magnetic anisotropy presents a competition between magnetocrystalline (biaxial) and substrate step induced (uniaxial) anisotropy. Depending upon their relative strengths, a profound biaxial or uniaxial or mixed anisotropy is favoured. Above the critical thickness, magnetocrystalline anisotropy dominates all other effects and shows a biaxial anisotropy.

Should the history of epidemiology be taught in epidemiology training programs?

Science.gov (United States)

Laskaris, Zoey; Morabia, Alfredo

2015-01-01

Currently, there is no evidence concerning the presence of historical content in the epidemiology curricula of the United States and abroad. Similarly, it is not known how epidemiologists view this topic in the context of master's or doctoral level course work. We attempted to fill these knowledge gaps with data from 2 online surveys-Survey I administered to persons in charge of all epidemiology training programs in North America and Survey II to epidemiologists practicing around the world. A substantial minority (39%) of graduate programs in epidemiology in the United States teach a course on the history of the field. In both surveys, the most common reasons selected for teaching such a course were "To build a sense of identity as an epidemiologist" and "As a tool for achieving a deeper understanding into specific methods and concepts." The majority of respondents, from 63 countries, agreed that the history of epidemiology should be included in curricula for graduate students in epidemiology.

Modelo Vectorial para la Inferencia del Estado Cognitivo de Pacientes en Estados Derivados del Coma

Directory of Open Access Journals (Sweden)

Esteban Velásquez R.

2014-06-01

Full Text Available La forma tradicional de evaluar el estado de conciencia de un individuo, ha sido mediante la aplicación de estímulos y el análisis de sus respuestas, sin embargo, esta técnica se ve limitada cuando el individuo es incapaz de responder evidentemente ante un estímulo, como es el caso de los pacientes en estados derivados del coma. En estos casos, se requiere de una conexión directa con el cerebro del paciente para detectar una respuesta. Por consiguiente, en este artículo se desarrolla y analiza un modelo computacional basado en los principios de las máquinas de soporte vectorial (MSV, para inferir el estado cognitivo de pacientes en estados derivados del coma, mediante la utilización de un equipo de electroencefalografía comercial. Los resultados obtenidos, mostraron que el modelo logró clasificar correctamente una tarea cognitiva en al menos cuatro de cada cinco pruebas en pacientes de control, lo que se traduce en la obtención de un sistema de bajo costo para el análisis del estado de conciencia y para la posible comunicación con algunos pacientes en estados derivados del coma mediante protocolos médicos definidos. De esta manera, este sistema se presenta como un gran aporte para las clínicas y centros hospitalarios, como herramienta potencial de diagnóstico para este tipo de pacientes.

Microorganism-mediated behaviour of malaria mosquitoes

NARCIS (Netherlands)

Busula, Annette O.

2017-01-01

Host-seeking is an important component of mosquito vectorial capacity on which the success of the other behavioural determinants depends. Blood-seeking mosquitoes are mainly guided by chemical cues released by their blood hosts. This thesis describes results of a study that determined the effect

Role of Genomic Typing in Taxonomy, Evolutionary Genetics, and Microbial Epidemiology

Science.gov (United States)

van Belkum, Alex; Struelens, Marc; de Visser, Arjan; Verbrugh, Henri; Tibayrenc, Michel

2001-01-01

Currently, genetic typing of microorganisms is widely used in several major fields of microbiological research. Taxonomy, research aimed at elucidation of evolutionary dynamics or phylogenetic relationships, population genetics of microorganisms, and microbial epidemiology all rely on genetic typing data for discrimination between genotypes. Apart from being an essential component of these fundamental sciences, microbial typing clearly affects several areas of applied microbiogical research. The epidemiological investigation of outbreaks of infectious diseases and the measurement of genetic diversity in relation to relevant biological properties such as pathogenicity, drug resistance, and biodegradation capacities are obvious examples. The diversity among nucleic acid molecules provides the basic information for all fields described above. However, researchers in various disciplines tend to use different vocabularies, a wide variety of different experimental methods to monitor genetic variation, and sometimes widely differing modes of data processing and interpretation. The aim of the present review is to summarize the technological and fundamental concepts used in microbial taxonomy, evolutionary genetics, and epidemiology. Information on the nomenclature used in the different fields of research is provided, descriptions of the diverse genetic typing procedures are presented, and examples of both conceptual and technological research developments for Escherichia coli are included. Recommendations for unification of the different fields through standardization of laboratory techniques are made. PMID:11432813

[The control of vectorial transmission].

Science.gov (United States)

Silveira, Antônio Carlos; Dias, João Carlos Pinto

2011-01-01

of human infection directly related to the enzootic cycle of the parasite. By all these reasons, it is still indispensable the maintenance of a strict epidemiological surveillance against Chagas Disease in Brazil.

Epidemiology of IBD

Science.gov (United States)

... IBD? Projects and Partners Data and Statistics Resources Epidemiology of the IBD Recommend on Facebook Tweet Share ... 5:1424-9. 2 Loftus EV, Jr. Clinical epidemiology of inflammatory bowel disease: Incidence, prevalence, and environmental ...

The New Epidemiology--A Challenge to Health Administration. Issues in Epidemiology for Administration.

Science.gov (United States)

Crichton, Anne, Ed.; Neuhauser, Duncan, Ed.

The role of epidemiology in health administration is considered in 11 articles, and three course descriptions and a bibliography are provided. Titles and authors include the following: "The Need for Creative Managerial Epidemiology" (Gary L. Filerman); "The Growing Role of Epidemiology in Health Administration" (Maureen M.…

Ebola virus disease outbreak; the role of field epidemiology training programme in the fight against the epidemic, Liberia, 2014.

Science.gov (United States)

Lubogo, Mutaawe; Donewell, Bangure; Godbless, Lucas; Shabani, Sasita; Maeda, Justin; Temba, Herilinda; Malibiche, Theophil C; Berhanu, Naod

2015-01-01

The African Field Epidemiology Network (AFENET) is a public health network established in 2005 as a non-profit networking alliance of Field Epidemiology and Laboratory Training Programs (FELTPs) and Field Epidemiology Training Programs (FETPs) in Africa. AFENET is dedicated to supporting Ministries of Health in Africa build strong, effective and sustainable programs and capacity to improve public health systems by partnering with global public health experts. The Network's goal is to strengthen field epidemiology and public health laboratory capacity to contribute effectively to addressing epidemics and other major public health problems in Africa. The goal for the establishment of FETP and FELTP was and still is to produce highly competent multi-disciplinary public health professionals who would assume influential posts in the public health structures and tackle emerging and re-emerging communicable and non-communicable diseases. AFENET currently networks 12 FELTPs and FETPs in sub-Saharan Africa with operations in 20 countries. During the Ebola Virus Disease (EVD) outbreak in West Africa, African Union Support for the Ebola Outbreak in West Africa (ASEOWA) supported FETP graduates from Uganda, Zimbabwe, Ethiopia and Tanzania for the investigation and control of the EVD outbreak in Liberia. The graduates were posted in different counties in Liberia where they lead teams of other experts conduct EVD outbreak investigations, Infection Control and Prevention trainings among health workers and communities, Strengthening integrated disease surveillance, developing Standard Operating Procedures for infection control and case notification in the Liberian setting as well as building capacity of local surveillance officers' conduct outbreak investigation and contact tracing. The team was also responsible for EVD data management at the different Counties in Liberia. The FETP graduates have been instrumental in the earlier successes registered in various counties in Liberia

Building local capacity for genomics research in Africa: recommendations from analysis of publications in Sub-Saharan Africa from 2004 to 2013.

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Adedokun, Babatunde O; Olopade, Christopher O; Olopade, Olufunmilayo I

2016-01-01

The poor genomics research capacity of Sub-Saharan Africa (SSA) could prevent maximal benefits from the applications of genomics in the practice of medicine and research. The objective of this study is to examine the author affiliations of genomic epidemiology publications in order to make recommendations for building local genomics research capacity in SSA. SSA genomic epidemiology articles published between 2004 and 2013 were extracted from the Human Genome Epidemiology (HuGE) database. Data on authorship details, country of population studied, and phenotype or disease were extracted. Factors associated with the first author, who has an SSA institution affiliation (AIAFA), were determined using a Chi-square test and multiple logistic regression analysis. The most commonly studied population was South Africa, accounting for 31.1%, followed by Ghana (10.6%) and Kenya (7.5%). About one-tenth of the papers were related to non-communicable diseases (NCDs) such as cancer (6.1%) and cardiovascular diseases (CVDs) (4.3%). Fewer than half of the first authors (46.9%) were affiliated with an African institution. Among the 238 articles with an African first author, over three-quarters (79.8%) belonged to a university or medical school, 16.8% were affiliated with a research institute, and 3.4% had affiliations with other institutions. Significant disparities currently exist among SSA countries in genomics research capacity. South Africa has the highest genomics research output, which is reflected in the investments made in its genomics and biotechnology sector. These findings underscore the need to focus on developing local capacity, especially among those affiliated with SSA universities where there are more opportunities for teaching and research.

A physiological time analysis of the duration of the gonotrophic cycle of Anopheles pseudopunctipennis and its implications for malaria transmission in Bolivia

Directory of Open Access Journals (Sweden)

Quispe Vicente

2008-07-01

Full Text Available Abstract Background The length of the gonotrophic cycle varies the vectorial capacity of a mosquito vector and therefore its exact estimation is important in epidemiological modelling. Because the gonotrophic cycle length depends on temperature, its estimation can be satisfactorily computed by means of physiological time analysis. Methods A model of physiological time was developed and calibrated for Anopheles pseudopunctipennis, one of the main malaria vectors in South America, using data from laboratory temperature controlled experiments. The model was validated under varying temperatures and could predict the time elapsed from blood engorgement to oviposition according to the temperature. Results In laboratory experiments, a batch of An. pseudopunctipennis fed at the same time may lay eggs during several consecutive nights (2–3 at high temperature and > 10 at low temperature. The model took into account such pattern and was used to predict the range of the gonotrophic cycle duration of An. pseudopunctipennis in four characteristic sites of Bolivia. It showed that the predicted cycle duration for An. pseudopunctipennis exhibited a seasonal pattern, with higher variances where climatic conditions were less stable. Predicted mean values of the (minimum duration ranged from 3.3 days up to > 10 days, depending on the season and the geographical location. The analysis of ovaries development stages of field collected biting mosquitoes indicated that the phase 1 of Beklemishev might be of significant duration for An. pseudopunctipennis. The gonotrophic cycle length of An. pseudopunctipennis correlates with malaria transmission patterns observed in Bolivia which depend on locations and seasons. Conclusion A new presentation of cycle length results taking into account the number of ovipositing nights and the proportion of mosquitoes laying eggs is suggested. The present approach using physiological time analysis might serve as an outline to other

Bioimpedancia vectorial y espectroscópica: valoración del estado de hidratación con ambos métodos en hemodiálisis Bioimpedance vector and spectroscopic analysis: assessing hydration status using both methods in haemodialysis

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Ruth Ros Nogales

2013-03-01

Full Text Available El análisis de bioimpedancia es una herramienta útil para determinar el estado nutricional y de hidratación del enfermo en hemodiálisis. Los dos sistemas más utilizados son la bioimpedancia de monofrecuencia vectorial y la bioimpedancia multifrecuencia espectroscópica que utilizan diferentes criterios para clasificar el estado de hidratación del enfermo dializado. El sistema de bioimpedancia de monofrecuencia vectorial utiliza una escala ordinal de 7 puntos que va desde el valor 3 (mayor hidratación hasta el valor -3 (mayor deshidratación definiendo la hiperhidratación cuando el vector está en el eje de hidratación por debajo de la elipse de tolerancia del 75% (valores 3 y 2 de la escala ordinal. El sistema de bioimpedancia multifrecuencia espectroscópica emplea dos criterios para definir el estado de hiperhidratación prediálisis: OH superior a 2,5 litros o mayor del 15% del volumen de agua extracelular. El objetivo del presente trabajo fue analizar el grado de concordancia entre ambos sistemas de bioimpedancia para definir el estado de hiperhidratación en enfermos tratados con hemodiálisis. Se llevó a cabo un estudio transversal en 54 enfermos tratados con hemodiálisis a los que se les realizó un análisis de bioimpedancia con monitores de monofrecuencia vectorial y multifrecuencia espectroscópica inmediatamente antes de una sesión de hemodiálisis. El grado de equivalencia en la definición de hiperhidratación entre ambos monitores fue mejor cuando se utilizó, en el monitor de multifrecuencia, el criterio de OH>15% del agua extracelular (índice kappa 0.81, concordancia excelente que cuando se utilizó el criterio de OH>2,5 litros (índice kappa 0.71, concordancia aceptable. Conclusiones: Hay una buena relación entre la escala vectorial de hidratación y el valor OH (exceso de hidratación. Los criterios utilizados por los monitores de monofrecuencia vectorial y multifrecuencia espectroscópica para definir los estados

WHO - IPHECA: Epidemiological aspects

International Nuclear Information System (INIS)

Souchkevitch, G.

1996-01-01

In May 1991 the World Health Assembly endorsed the establishment of the International Programme on the Health Effects of the Chernobyl Accident (IPHECA) under the auspices of WHO. Five pilot projects have been carried out within IPHECA in the study territories of Belarus, Russian Federation and Ukraine in a period from 1991 to 1994. This pilot projects dealt with the detection and treatment of leukaemia and related diseases (Haematology Project), thyroid disorders (Thyroid project), brain damage during exposure 'in-utero' (Brain Damage 'in-Utero' project) and with the development of the Chernobyl registries (Epidemiological Registry Project). A fifth pilot project on oral health was performed only in Belarus. Epidemiological investigations have been an important component of all IPHECA pilot projects. Within 'Epidemiological Registry' Project such investigations have been the principal activity. But with respect to other IPHECA projects it was carried out in addition to main objectives relating to medical monitoring, early diagnosis and treatment of specific diseases included in project protocols. To support the epidemiological investigations within IPHECA, WHO supplied 41 computers in Belarus, Russian Federation and Ukraine and provided training for specialists from these countries in internationally recognized centres. The training programmes and host countries were as follows: standardization of epidemiological investigations (United Kingdom), radiation epidemiology (Russia), development of software (United Kingdom), principles of epidemiological investigations (The Czech Republic), cohort investigations (Japan)

WHO - IPHECA: Epidemiological aspects

Energy Technology Data Exchange (ETDEWEB)

Souchkevitch, G [World Health Organization, Geneva (Swaziland)

1996-07-01

In May 1991 the World Health Assembly endorsed the establishment of the International Programme on the Health Effects of the Chernobyl Accident (IPHECA) under the auspices of WHO. Five pilot projects have been carried out within IPHECA in the study territories of Belarus, Russian Federation and Ukraine in a period from 1991 to 1994. This pilot projects dealt with the detection and treatment of leukaemia and related diseases (Haematology Project), thyroid disorders (Thyroid project), brain damage during exposure 'in-utero' (Brain Damage 'in-Utero' project) and with the development of the Chernobyl registries (Epidemiological Registry Project). A fifth pilot project on oral health was performed only in Belarus. Epidemiological investigations have been an important component of all IPHECA pilot projects. Within 'Epidemiological Registry' Project such investigations have been the principal activity. But with respect to other IPHECA projects it was carried out in addition to main objectives relating to medical monitoring, early diagnosis and treatment of specific diseases included in project protocols. To support the epidemiological investigations within IPHECA, WHO supplied 41 computers in Belarus, Russian Federation and Ukraine and provided training for specialists from these countries in internationally recognized centres. The training programmes and host countries were as follows: standardization of epidemiological investigations (United Kingdom), radiation epidemiology (Russia), development of software (United Kingdom), principles of epidemiological investigations (The Czech Republic), cohort investigations (Japan)

Methodologic frontiers in environmental epidemiology.

OpenAIRE

Rothman, K J

1993-01-01

Environmental epidemiology comprises the epidemiologic study of those environmental factors that are outside the immediate control of the individual. Exposures of interest to environmental epidemiologists include air pollution, water pollution, occupational exposure to physical and chemical agents, as well as psychosocial elements of environmental concern. The main methodologic problem in environmental epidemiology is exposure assessment, a problem that extends through all of epidemiologic re...

Ross, macdonald, and a theory for the dynamics and control of mosquito-transmitted pathogens.

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Smith, David L; Battle, Katherine E; Hay, Simon I; Barker, Christopher M; Scott, Thomas W; McKenzie, F Ellis

2012-01-01

Ronald Ross and George Macdonald are credited with developing a mathematical model of mosquito-borne pathogen transmission. A systematic historical review suggests that several mathematicians and scientists contributed to development of the Ross-Macdonald model over a period of 70 years. Ross developed two different mathematical models, Macdonald a third, and various "Ross-Macdonald" mathematical models exist. Ross-Macdonald models are best defined by a consensus set of assumptions. The mathematical model is just one part of a theory for the dynamics and control of mosquito-transmitted pathogens that also includes epidemiological and entomological concepts and metrics for measuring transmission. All the basic elements of the theory had fallen into place by the end of the Global Malaria Eradication Programme (GMEP, 1955-1969) with the concept of vectorial capacity, methods for measuring key components of transmission by mosquitoes, and a quantitative theory of vector control. The Ross-Macdonald theory has since played a central role in development of research on mosquito-borne pathogen transmission and the development of strategies for mosquito-borne disease prevention.

Macrofilaricides and onchocerciasis control, mathematical modelling of the prospects for elimination

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Lazdins Janis

2001-11-01

Full Text Available Abstract Background In most endemic parts of the world, onchocerciasis (river blindness control relies, or will soon rely, exclusively on mass treatment with the microfilaricide ivermectin. Worldwide eradication of the parasite by means of this drug is unlikely. Macrofilaricidal drugs are currently being developed for human use. Methods We used ONCHOSIM, a microsimulation mathematical model of the dynamics of onchocerciasis transmission, to explore the potentials of a hypothetical macrofilaricidal drug for the elimination of onchocerciasis under different epidemiological conditions, as characterized by previous intervention strategies, vectorial capacity and levels of coverage. Results With a high vector biting rate and poor coverage, a very effective macrofilaricide would appear to have a substantially higher potential for achieving elimination of the parasite than does ivermectin. Conclusions Macrofilaricides have a substantially higher potential for achieving onchocerciasis elimination than ivermectin, but high coverage levels are still key. When these drugs become available, onchocerciasis elimination strategies should be reconsidered. In view of the impact of control efforts preceding the introduction of macrofilaricides on the success of elimination, it is important to sustain current control efforts.

Epidemiological causality.

Science.gov (United States)

Morabia, Alfredo

2005-01-01

Epidemiological methods, which combine population thinking and group comparisons, can primarily identify causes of disease in populations. There is therefore a tension between our intuitive notion of a cause, which we want to be deterministic and invariant at the individual level, and the epidemiological notion of causes, which are invariant only at the population level. Epidemiologists have given heretofore a pragmatic solution to this tension. Causal inference in epidemiology consists in checking the logical coherence of a causality statement and determining whether what has been found grossly contradicts what we think we already know: how strong is the association? Is there a dose-response relationship? Does the cause precede the effect? Is the effect biologically plausible? Etc. This approach to causal inference can be traced back to the English philosophers David Hume and John Stuart Mill. On the other hand, the mode of establishing causality, devised by Jakob Henle and Robert Koch, which has been fruitful in bacteriology, requires that in every instance the effect invariably follows the cause (e.g., inoculation of Koch bacillus and tuberculosis). This is incompatible with epidemiological causality which has to deal with probabilistic effects (e.g., smoking and lung cancer), and is therefore invariant only for the population.

Prevalence rates and epidemiological risk factors for astigmatism in Singapore school children.

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Tong, Louis; Saw, Seang-Mei; Carkeet, Andrew; Chan, Wai-Ying; Wu, Hui-Min; Tan, Donald

2002-09-01

This study examined the prevalence rate of astigmatism and its epidemiological risk factors in Singapore school children. In a study of school children aged 7 to 9 years old in two schools in Singapore in 1999, a detailed questionnaire was administered to parents regarding reading or close-work habits, past history of close-work, family history, and socioeconomic factors. Cycloplegic refraction was performed five times in each eye. Defining astigmatism as worse than or equal to 0.5, 0.75, and 1 D cylinder in the right eye, the prevalence of astigmatism was calculated. The study population consisted of 1028 children. The prevalence rate of astigmatism (worse than or equal to 1 D cylinder) was 19.2% (95% confidence interval, 16.8 to 21.6). This was not different between genders, ethnic groups, or age (p > 0.05). With-the-rule astigmatism was more common than against-the-rule astigmatism. The prevalence of astigmatism and myopia was 9.8% (95% confidence interval, 8.0 to 11.6). A high AC/A ratio was associated (p = 0.003) with astigmatism, even after exclusion of myopic children. On vectorial analysis, J0 and J45 were associated with the number of hours of playing video games, whereas J45 was also associated with computer use. Only J45 was associated to male gender, a high AC/A ratio, and a family history of myopia. The prevalence rate of astigmatism (> or = 1 D) was 19%. Playing video games and computer use may be associated with astigmatism severity, although the presence of astigmatism (> or = 1 D) was not associated with any nearwork factors. A family history of myopia was associated with oblique astigmatism severity. A high AC/A ratio is associated with astigmatism, and this requires further investigation.

Epidemiology: Then and Now.

Science.gov (United States)

Kuller, Lewis H

2016-03-01

Twenty-five years ago, on the 75th anniversary of the Johns Hopkins Bloomberg School of Public Health, I noted that epidemiologic research was moving away from the traditional approaches used to investigate "epidemics" and their close relationship with preventive medicine. Twenty-five years later, the role of epidemiology as an important contribution to human population research, preventive medicine, and public health is under substantial pressure because of the emphasis on "big data," phenomenology, and personalized medical therapies. Epidemiology is the study of epidemics. The primary role of epidemiology is to identify the epidemics and parameters of interest of host, agent, and environment and to generate and test hypotheses in search of causal pathways. Almost all diseases have a specific distribution in relation to time, place, and person and specific "causes" with high effect sizes. Epidemiology then uses such information to develop interventions and test (through clinical trials and natural experiments) their efficacy and effectiveness. Epidemiology is dependent on new technologies to evaluate improved measurements of host (genomics), epigenetics, identification of agents (metabolomics, proteomics), new technology to evaluate both physical and social environment, and modern methods of data collection. Epidemiology does poorly in studying anything other than epidemics and collections of numerators and denominators without specific hypotheses even with improved statistical methodologies. © The Author 2015. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Epidemiology and the Tobacco Epidemic: How Research on Tobacco and Health Shaped Epidemiology.

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Samet, Jonathan M

2016-03-01

In this article, I provide a perspective on the tobacco epidemic and epidemiology, describing the impact of the tobacco-caused disease epidemic on the field of epidemiology. Although there is an enormous body of epidemiologic evidence on the associations of smoking with health, little systematic attention has been given to how decades of research have affected epidemiology and its practice. I address the many advances that resulted from epidemiologic research on smoking and health, such as demonstration of the utility of observational designs and important parameters (the odds ratio and the population attributable risk), guidelines for causal inference, and systematic review approaches. I also cover unintended and adverse consequences for the field, including the strategy of doubt creation and the recruitment of epidemiologists by the tobacco industry to serve its mission. The paradigm of evidence-based action for addressing noncommunicable diseases began with the need to address the epidemic of tobacco-caused disease, an imperative for action documented by epidemiologic research. © The Author 2016. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Epidemiology applied to health physics

International Nuclear Information System (INIS)

1983-01-01

The technical program of the mid-year meeting of the Health Physics Society, entitled Epidemiology Applied to Health physics, was developed to meet three objectives: (1) give health physicists a deeper understanding of the basics of epidemiological methods and their use in developing standards, regulations, and criteria and in risk assessment; (2) present current reports on recently completed or on-going epidemiology studies; and (3) encourage greater interaction between the health physics and epidemiology disciplines. Included are studies relating methods in epidemiology to radiation protection standards, risk assessment from exposure to bone-seekers, from occupational exposures in mines, mills and nuclear facilities, and from radioactivity in building materials

CEDR: Comprehensive Epidemiologic Data Resource

Energy Technology Data Exchange (ETDEWEB)

1993-08-01

The Department of Energy (DOE) and its predecessor agencies have a long history of epidemiologic research programs. The main focus of these programs has been the Health and Mortality Study of the DOE work force. This epidemiologic study began in 1964 with a feasibility study of workers at the Hanford facility. Studies of other populations exposed to radiation have also been supported, including the classic epidemiologic study of radium dial painters and studies of atomic bomb survivors. From a scientific perspective, these epidemiologic research program have been productive, highly credible, and formed the bases for many radiological protection standards. Recently, there has been concern that, although research results were available, the data on which these results were based were not easily obtained by interested investigators outside DOE. Therefore, as part of an effort to integrate and broaden access to its epidemiologic information, the DOE has developed the Comprehensive Epidemiologic Data Resource (CEDR) Program. Included in this effort is the development of a computer information system for accessing the collection of CEDR data and its related descriptive information. The epidemiologic data currently available through the CEDAR Program consist of analytic data sets, working data sets, and their associated documentation files. In general, data sets are the result of epidemiologic studies that have been conducted on various groups of workers at different DOE facilities during the past 30 years.

Mapping epidemiology's past to inform its future: metaknowledge analysis of epidemiologic topics in leading journals, 1974-2013.

Science.gov (United States)

Trinquart, Ludovic; Galea, Sandro

2015-07-15

An empiric perspective on what epidemiology has studied over time might inform discussions about future directions for the discipline. We aimed to identify the main areas of epidemiologic inquiry and determine how they evolved over time in 5 high-impact epidemiologic journals. We analyzed the titles and abstracts of 20,895 articles that were published between 1974 and 2013. In 5 time periods that reflected approximately equal numbers of articles, we identified the main topics by clustering terms based on co-occurrence. Infectious disease and cardiovascular disease epidemiology were the prevailing topics over the 5 periods. Cancer epidemiology was a major topic from 1974 to 2001 but disappeared thereafter. Nutritional epidemiology gained relative importance from 1974 to 2013. Environmental epidemiology appeared during 1996-2001 and continued to be important, whereas 2 clusters related to methodology and meta-analysis in genetics appeared during 2008-2013. Several areas of epidemiology, including injury or psychiatric epidemiology, did not make an appearance as major topics at any time. In an ancillary analysis of 6 high-impact general medicine journals, we found patterns of epidemiologic articles that were overall consistent with the findings in epidemiologic journals. This metaknowledge investigation allowed identification of the dominant topics in and conversely those that were absent from 5 major epidemiologic journals. We discuss implications for the field. © The Author 2015. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

International Lymphoma Epidemiology Consortium

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The InterLymph Consortium, or formally the International Consortium of Investigators Working on Non-Hodgkin's Lymphoma Epidemiologic Studies, is an open scientific forum for epidemiologic research in non-Hodgkin's lymphoma.

Against Popperized epidemiology.

Science.gov (United States)

Jacobsen, M

1976-03-01

The recommendation of Popper's philosophy of science should be adopted by epidemiologists is disputed. Reference is made to other authors who have shown that the most constructive elements in Popper's ideas have been advocated by earlier philosophers and have been used in epidemiology without abandoning inductive reasoning. It is argued that Popper's denigration of inductive methods is particularly harmful to epidemiology. Inductive reasoning and statistical inference play a key role in the science; it is suggested that unfamiliarity with these ideas contributes to widespread misunderstanding of the function of epidemiology. Attention is drawn to a common fallacy involving correlations between three random variables. The prevalence of the fallacy may be related to confusion between deductive and inductive logic.

Depressive Symptoms, Exercise Capacity, and Clinical Outcomes After Lung Transplantation.

Science.gov (United States)

Smith, Patrick J; Byrd, Rebecca; Lusby, Megan; Clausen, Emily; Snyder, Laurie D

2018-05-01

Depressive symptoms are common among lung transplant recipients and have been associated with worse clinical outcomes. However, few studies have examined the association between depressive symptoms assessed at multiple time points or behavioral mechanisms by which posttransplant depressive symptoms may confer greater clinical risk. We therefore examined the associations between depressive symptoms, exercise capacity, chronic lung allograft dysfunction (CLAD), and mortality prospectively in a large sample of lung transplant recipients. Between July 2009 and February 2016, 251 lung transplant recipients were assessed before transplantation and again approximately 3 weeks and 3 months after transplant. Depressive symptoms were assessed using the Centers for Epidemiologic Studies of Depression scale. Functional exercise capacity was assessed using the 6-minute walk test. Cox proportional hazards models were used to examine the associations between depressive symptoms, exercise capacity, CLAD, and mortality. During a median (range) follow-up of 4.5 (0.1 to 6.3) years, 53 participants (21%) died. Greater depressive symptoms (hazard ratio [HR] = 1.39 [95% CI = 1.05 to 1.84], p = .021) and poorer exercise capacity (HR = 0.58 [95% CI = 0.38 to 0.90], p = .021) assessed 3 months after transplant were both independently associated with mortality. Although greater depressive symptoms were associated with lower exercise capacity (β = -0.14, p = .039), exercise capacity did not mediate the association between depressive symptoms and mortality. In secondary analyses, depressive symptoms were independently predictive of CLAD (HR = 1.29 [95% CI = 1.01 to 1.65], p = .045) and the composite outcome of CLAD and mortality in a clustered event model (HR = 1.30 [1.09 to 1.56], p = .005). Depressive symptoms are associated with mortality and CLAD after lung transplantation, independent of exercise capacity.

Development and application of Human Genome Epidemiology

Science.gov (United States)

Xu, Jingwen

2017-12-01

Epidemiology is a science that studies distribution of diseases and health in population and its influencing factors, it also studies how to prevent and cure disease and promote health strategies and measures. Epidemiology has developed rapidly in recent years and it is an intercross subject with various other disciplines to form a series of branch disciplines such as Genetic epidemiology, molecular epidemiology, drug epidemiology and tumor epidemiology. With the implementation and completion of Human Genome Project (HGP), Human Genome Epidemiology (HuGE) has emerged at this historic moment. In this review, the development of Human Genome Epidemiology, research content, the construction and structure of relevant network, research standards, as well as the existing results and problems are briefly outlined.

Theoretical and experimental study of stochastic effects on polarization rotation in a vectorial bistable laser

International Nuclear Information System (INIS)

Singh, Kamal P.; Ropars, Guy; Brunel, Marc; Le Floch, Albert

2006-01-01

We investigate the two-dimensional optical rotor of a weakly modulated vectorial bistable laser submitted to a single or multiple stochastic perturbations. In the Langevin-type equation of the rotor the role of an even or odd input forcing function on the system dynamics is isolated. Through these two inputs of optical and magnetic natures we verify that the stochastic resonance exists only when the periodic modulation acts on the even parity optical input. When two mutually correlated noises are simultaneously submitted to the input functions of opposite parities, we find a critical regime of the noise interplay whereby one stable state becomes noise-free. In this case, the residence time of the light vector in the noise-free state diverges which leads to a collapse of the output signal-to-noise ratio. But, in this critical regime also obtained when one noise drives both the even and odd functions, if the system symmetry is broken through an independent lever control, we can recover the switching cycle due to a new response mechanism, namely, the dual stochastic response, with a specific output signal-to-noise ratio expression. Both the theoretical analysis and the experiment show that the signal-to-noise ratio now displays a robust behavior for a large range of the input noise amplitude, and a plateau with respect to the input signal amplitude. Furthermore, we isolate an original signature of this synchronization mechanism in the residence-time distribution leading to a broadband forcing frequency range. These noise interplay effects in a double well potential are of generic nature and could be found in other nonlinear systems

Assessing the vulnerability of Brazilian municipalities to the vectorial transmission of Trypanosoma cruzi using multi-criteria decision analysis.

Science.gov (United States)

Vinhaes, Márcio Costa; de Oliveira, Stefan Vilges; Reis, Priscilleyne Ouverney; de Lacerda Sousa, Ana Carolina; Silva, Rafaella Albuquerque E; Obara, Marcos Takashi; Bezerra, Cláudia Mendonça; da Costa, Veruska Maia; Alves, Renato Vieira; Gurgel-Gonçalves, Rodrigo

2014-09-01

Despite the dramatic reduction in Trypanosoma cruzi vectorial transmission in Brazil, acute cases of Chagas disease (CD) continue to be recorded. The identification of areas with greater vulnerability to the occurrence of vector-borne CD is essential to prevention, control, and surveillance activities. In the current study, data on the occurrence of domiciliated triatomines in Brazil (non-Amazonian regions) between 2007 and 2011 were analyzed. Municipalities' vulnerability was assessed based on socioeconomic, demographic, entomological, and environmental indicators using multi-criteria decision analysis (MCDA). Overall, 2275 municipalities were positive for at least one of the six triatomine species analyzed (Panstrongylus megistus, Triatoma infestans, Triatoma brasiliensis, Triatoma pseudomaculata, Triatoma rubrovaria, and Triatoma sordida). The municipalities that were most vulnerable to vector-borne CD were mainly in the northeast region and exhibited a higher occurrence of domiciliated triatomines, lower socioeconomic levels, and more extensive anthropized areas. Most of the 39 new vector-borne CD cases confirmed between 2001 and 2012 in non-Amazonian regions occurred within the more vulnerable municipalities. Thus, MCDA can help to identify the states and municipalities that are most vulnerable to the transmission of T. cruzi by domiciliated triatomines, which is critical for directing adequate surveillance, prevention, and control activities. The methodological approach and results presented here can be used to enhance CD surveillance in Brazil. Copyright © 2014 Elsevier B.V. All rights reserved.

Controlled Vectorial Electron Transfer and Photoelectrochemical Applications of Layered Relay/Photosensitizer-Imprinted Au Nanoparticle Architectures on Electrodes.

Science.gov (United States)

Metzger, Tzuriel S; Tel-Vered, Ran; Willner, Itamar

2016-03-23

Two configurations of molecularly imprinted bis-aniline-bridged Au nanoparticles (NPs) for the specific binding of the electron acceptor N,N'-dimethyl-4,4'-bipyridinium (MV(2+) ) and for the photosensitizer Zn(II)-protoporphyrin IX (Zn(II)-PP-IX) are assembled on electrodes, and the photoelectrochemical features of the two configurations are discussed. Configuration I includes the MV(2+) -imprinted Au NPs matrix as a base layer, on which the Zn(II)-PP-IX-imprinted Au NPs layer is deposited, while configuration II consists of a bilayer corresponding to the reversed imprinting order. Irradiation of the two electrodes in the presence of a benzoquinone/benzohydroquinone redox probe yields photocurrents of unique features: (i) Whereas configuration I yields an anodic photocurrent, the photocurrent generated by configuration II is cathodic. (ii) The photocurrents obtained upon irradiation of the imprinted electrodes are substantially higher as compared to the nonimprinted surfaces. The high photocurrents generated by the imprinted Au NPs-modified electrodes are attributed to the effective loading of the imprinted matrices with the MV(2+) and Zn(II)-PP-IX units and to the effective charge separation proceeding in the systems. The directional anodic/cathodic photocurrents are rationalized in terms of vectorial electron transfer processes dictated by the imprinting order and by the redox potentials of the photosensitizer/electron acceptor units associated with the imprinted sites in the two configurations. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Aerobic capacity mediates susceptibility for the transition from steatosis to steatohepatitis.

Science.gov (United States)

Morris, E Matthew; McCoin, Colin S; Allen, Julie A; Gastecki, Michelle L; Koch, Lauren G; Britton, Steven L; Fletcher, Justin A; Fu, Xiarong; Ding, Wen-Xing; Burgess, Shawn C; Rector, R Scott; Thyfault, John P

2017-07-15

) activation compared to HCR rats. Further, LCR rats had greater WD-induced decreases in complete FAO and mitochondrial respiratory capacity. Intrinsic aerobic capacity had no impact on WD-induced hepatic steatosis; however, rats bred for low aerobic capacity developed greater hepatic inflammation, which was associated with reduced hepatic mitochondrial FAO and respiratory capacity and increased accumulation of cholesterol esters. These results confirm epidemiological reports that aerobic capacity impacts progression of liver disease and suggest that these effects are mediated through alterations in hepatic mitochondrial function. © 2017 The Authors. The Journal of Physiology © 2017 The Physiological Society.

The application of epidemiology in national veterinary services: Challenges and threats in Brazil.

Science.gov (United States)

Gonçalves, Vitor Salvador Picão; de Moraes, Geraldo Marcos

2017-02-01

of expertise in veterinary epidemiology, as well as institutional models that provide an appropriate environment for building and sustaining capacity in national veterinary services. Integrating epidemiology with animal health policy is a great opportunity if epidemiologists can understand the real issues, including the socio-economic dimensions of disease management, and focus on innovation and production of knowledge. It may be a trap if epidemiologists are restricted to answering specific decision-making questions and policy makers perceive their role exclusively as data analysts or providers of technological solutions. Fostering solutions for complex issues is key to successful integration with policy making. Copyright © 2016 Elsevier B.V. All rights reserved.

The contribution of epidemiology

NARCIS (Netherlands)

Brandt, P. van den; Voorrips, L.; Hertz-Picciotto, I.; Shuker, D.; Boeing, H.; Speijers, G.; Guittard, C.; Kleiner, J.; Knowles, M.; Wolk, A.; Goldbohm, A.

2002-01-01

Epidemiologic studies directly contribute data on risk (or benefit) in humans as the investigated species, and in the full food intake range normally encountered by humans. This paper starts with introducing the epidemiologic approach, followed by a discussion of perceived differences between

The epidemiology and surveillance response to pandemic influenza A (H1N1) among local health departments in the San Francisco Bay Area.

Science.gov (United States)

Enanoria, Wayne T A; Crawley, Adam W; Tseng, Winston; Furnish, Jasmine; Balido, Jeannie; Aragón, Tomás J

2013-03-27

Public health surveillance and epidemiologic investigations are critical public health functions for identifying threats to the health of a community. Very little is known about how these functions are conducted at the local level. The purpose of the Epidemiology Networks in Action (EpiNet) Study was to describe the epidemiology and surveillance response to the 2009 pandemic influenza A (H1N1) by city and county health departments in the San Francisco Bay Area in California. The study also documented lessons learned from the response in order to strengthen future public health preparedness and response planning efforts in the region. In order to characterize the epidemiology and surveillance response, we conducted key informant interviews with public health professionals from twelve local health departments in the San Francisco Bay Area. In order to contextualize aspects of organizational response and performance, we recruited two types of key informants: public health professionals who were involved with the epidemiology and surveillance response for each jurisdiction, as well as the health officer or his/her designee responsible for H1N1 response activities. Information about the organization, data sources for situation awareness, decision-making, and issues related to surge capacity, continuity of operations, and sustainability were collected during the key informant interviews. Content and interpretive analyses were conducted using ATLAS.ti software. The study found that disease investigations were important in the first months of the pandemic, often requiring additional staff support and sometimes forcing other public health activities to be put on hold. We also found that while the Incident Command System (ICS) was used by all participating agencies to manage the response, the manner in which it was implemented and utilized varied. Each local health department (LHD) in the study collected epidemiologic data from a variety of sources, but only case reports

Recent advances in leishmaniosis in pet animals: epidemiology, diagnostics and anti-vectorial prophylaxis.

Science.gov (United States)

Gramiccia, M

2011-09-08

The leishmanioses are diseases caused by protozoa of the genus Leishmania, parasites infecting numerous mammal species, including humans, and transmitted by the bite of phlebotomine sand flies. They are a large group of diseases ranging over inter-tropical zones of America and Africa, and extend into temperate regions of Latin America, Europe and Asia. Pet animals are found infected with different Leishmania species but Leishmania infantum is the most widespread being dogs the main reservoir of zoonotic visceral leishmaniosis (ZVL). Dogs are very susceptible to this parasite and may suffer from a complex syndrome, canine leishmaniosis (CanL), one of the major zoonoses globally causing severe fatal disease in this animal. Infections in cats and horses have also been reported in areas where CanL is diagnosed. In Europe dogs and cats are common companion animals and their health is of great concern, therefore management of leishmaniosis in pets generally follows that of human ZVL. The recent spread of Leishmania infections in non-endemic territories has been monitored by means of canine surveys, which represent a suitable approach because of the dog's role as a sentinel host. New tools have been developed for the surveillance and control of ZVL. A number of insecticide-based preparations have been specifically registered for dog protection against sand fly bites, with elevated efficacy for both individual and mass protection. Copyright © 2011 Elsevier B.V. All rights reserved.

Recasting the theory of mosquito-borne pathogen transmission dynamics and control

Science.gov (United States)

Smith, David L.; Perkins, T. Alex; Reiner, Robert C.; Barker, Christopher M.; Niu, Tianchan; Chaves, Luis Fernando; Ellis, Alicia M.; George, Dylan B.; Le Menach, Arnaud; Pulliam, Juliet R. C.; Bisanzio, Donal; Buckee, Caroline; Chiyaka, Christinah; Cummings, Derek A. T.; Garcia, Andres J.; Gatton, Michelle L.; Gething, Peter W.; Hartley, David M.; Johnston, Geoffrey; Klein, Eili Y.; Michael, Edwin; Lloyd, Alun L.; Pigott, David M.; Reisen, William K.; Ruktanonchai, Nick; Singh, Brajendra K.; Stoller, Jeremy; Tatem, Andrew J.; Kitron, Uriel; Godfray, H. Charles J.; Cohen, Justin M.; Hay, Simon I.; Scott, Thomas W.

2014-01-01

Mosquito-borne diseases pose some of the greatest challenges in public health, especially in tropical and sub-tropical regions of the world. Efforts to control these diseases have been underpinned by a theoretical framework developed for malaria by Ross and Macdonald, including models, metrics for measuring transmission, and theory of control that identifies key vulnerabilities in the transmission cycle. That framework, especially Macdonald's formula for R0 and its entomological derivative, vectorial capacity, are now used to study dynamics and design interventions for many mosquito-borne diseases. A systematic review of 388 models published between 1970 and 2010 found that the vast majority adopted the Ross–Macdonald assumption of homogeneous transmission in a well-mixed population. Studies comparing models and data question these assumptions and point to the capacity to model heterogeneous, focal transmission as the most important but relatively unexplored component in current theory. Fine-scale heterogeneity causes transmission dynamics to be nonlinear, and poses problems for modeling, epidemiology and measurement. Novel mathematical approaches show how heterogeneity arises from the biology and the landscape on which the processes of mosquito biting and pathogen transmission unfold. Emerging theory focuses attention on the ecological and social context for mosquito blood feeding, the movement of both hosts and mosquitoes, and the relevant spatial scales for measuring transmission and for modeling dynamics and control. PMID:24591453

Recasting the theory of mosquito-borne pathogen transmission dynamics and control.

Science.gov (United States)

Smith, David L; Perkins, T Alex; Reiner, Robert C; Barker, Christopher M; Niu, Tianchan; Chaves, Luis Fernando; Ellis, Alicia M; George, Dylan B; Le Menach, Arnaud; Pulliam, Juliet R C; Bisanzio, Donal; Buckee, Caroline; Chiyaka, Christinah; Cummings, Derek A T; Garcia, Andres J; Gatton, Michelle L; Gething, Peter W; Hartley, David M; Johnston, Geoffrey; Klein, Eili Y; Michael, Edwin; Lloyd, Alun L; Pigott, David M; Reisen, William K; Ruktanonchai, Nick; Singh, Brajendra K; Stoller, Jeremy; Tatem, Andrew J; Kitron, Uriel; Godfray, H Charles J; Cohen, Justin M; Hay, Simon I; Scott, Thomas W

2014-04-01

Mosquito-borne diseases pose some of the greatest challenges in public health, especially in tropical and sub-tropical regions of the world. Efforts to control these diseases have been underpinned by a theoretical framework developed for malaria by Ross and Macdonald, including models, metrics for measuring transmission, and theory of control that identifies key vulnerabilities in the transmission cycle. That framework, especially Macdonald's formula for R0 and its entomological derivative, vectorial capacity, are now used to study dynamics and design interventions for many mosquito-borne diseases. A systematic review of 388 models published between 1970 and 2010 found that the vast majority adopted the Ross-Macdonald assumption of homogeneous transmission in a well-mixed population. Studies comparing models and data question these assumptions and point to the capacity to model heterogeneous, focal transmission as the most important but relatively unexplored component in current theory. Fine-scale heterogeneity causes transmission dynamics to be nonlinear, and poses problems for modeling, epidemiology and measurement. Novel mathematical approaches show how heterogeneity arises from the biology and the landscape on which the processes of mosquito biting and pathogen transmission unfold. Emerging theory focuses attention on the ecological and social context for mosquito blood feeding, the movement of both hosts and mosquitoes, and the relevant spatial scales for measuring transmission and for modeling dynamics and control.

Epidemiology and Radiation Protection

International Nuclear Information System (INIS)

1987-01-01

Epidemiology aims at providing direct evidence of the long term health effects in humans due to potentially dangerous exposures to various nuisance agents, including ionising radiation. Inappropriate interpretation and use of the results of epidemiological studies may result in inaccurate assessments of the risks associated with radiation exposure. This report presents the proceedings of a Workshop organised by the NEA to create an opportunity for epidemiologists and radiation protection specialists to exchange their experiences and views on the problems of methodology in epidemiological research and on the application of its results to the assessment of radiation risks

16 CFR 1000.26 - Directorate for Epidemiology.

Science.gov (United States)

2010-01-01

... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Directorate for Epidemiology. 1000.26... AND FUNCTIONS § 1000.26 Directorate for Epidemiology. The Directorate for Epidemiology, managed by the Associate Executive Director for Epidemiology, is responsible for the collection and analysis of data on...

[Scientific, practical and educational aspects of clinical epidemiology].

Science.gov (United States)

Briko, N I

2012-01-01

This article defines clinical epidemiology and describes its goal and objectives. The author claims that clinical epidemiology is a section of epidemiology which underlies the development of evidence-based standards for diagnostics, treatment and prevention and helps to select the appropriate algorithm for each clinical case. The study provides a comprehensive overview of the relationship between clinical epidemiology and evidence-based medicine. Epidemiological research is shown to be methodological basis of clinical epidemiology and evidence-based medicine with randomized controlled trials being the "gold standard" for obtaining reliable data. The key stages in the history of clinical epidemiology are discussed and further development of clinical epidemiology and the integration of courses on clinical epidemiology in education is outlined for progress in medical research and health care practice.

Investing in African research training institutions creates sustainable capacity for Africa: the case of the University of the Witwatersrand School of Public Health masters programme in epidemiology and biostatistics

Science.gov (United States)

2012-01-01

Background Improving health in Africa is a high priority internationally. Inadequate research capacity to produce local, relevant research has been identified as a limitation to improved population health. Increasing attention is being paid to the higher education sector in Africa as a method of addressing this; evidence that such investment is having the desired impact is required. A 1998 3-year investment by the Special Programme for Research and Training in Tropical Diseases (TDR) in research training at the School of Public Health, University of the Witwatersrand, South Africa was reviewed to assess its' impact. Methods A descriptive cross-sectional survey of the 70 students registered for the masters programme in epidemiology & biostatistics from 2000-2005 was conducted. Data were collected from self-administered questionnaires. Results Sixty percent (42/70) of students responded. At the time of the survey 19% of respondents changed their country of residence after completion of the masters course, 14% migrated within Africa and 5% migrated out of Africa. Approximately half (47%) were employed as researchers and 38% worked in research institutions. Sixty percent reported research output, and four graduates were pursuing PhD studies. Government subsidy to higher education institutions, investments of the University of the Witwatersrand in successful programmes and ongoing bursaries for students to cover tuition fees were important for sustainability. Conclusions Investing in African institutions to improve research training capacity resulted in the retention of graduates in Africa in research positions and produced research output. Training programmes can be sustained when national governments invest in higher education and where that funding is judiciously applied. Challenges remain if funding for students bursaries is not available. PMID:22475629

History and philosophy of modern epidemiology

DEFF Research Database (Denmark)

Andersen, Hanne

2012-01-01

Epidemiological studies of chronic diseases began around the mid-20th century. Contrary to the infectious disease epidemiology which had prevailed at the beginning of the 20th century and which had focused on single agents causing individual diseases, the chronic disease epidemiology which emerge...

[Endocrine disruptors : Evidence from epidemiological studies necessitates a critical review of model systems].

Science.gov (United States)

Hoffmann, M; Gebauer, S; Nüchter, M; Baber, R; Ried, J; von Bergen, M; Kiess, W

2017-06-01

Endocrine disruptive chemicals (EDCs) cause adverse health effects through interaction with endocrine systems. They are classified by chemical structure, effects on specific endocrine systems, bioaccumulation, persistence in the environment, or clinically observable effects. For research of the complex mechanisms of action in the human body, only in vitro model systems have so far been available, that have insufficient high-throughput capacity, which makes risk evaluation more difficult. In addition, in industrial nations, living people are often exposed to mixtures of substances, with various effects. The clinical importance of epigenetic changes caused by the action of EDCs during vulnerable phases of development is currently unclear. Epidemiological studies are criticized because reproducibility is not always guaranteed. Nevertheless, they remain the method of choice for the development and analysis of suitable model systems. Positive associations, in spite of sometimes conflicting results, are key in the selection of factors that can then be analysed in model systems in an unbiased way. This article depicts the mainly positive epidemiological findings for EDC-caused effects in the fields of growth and metabolism, neurocognitive development and sexual development and reproduction. As a result, there is a need for closer linkage between epidemiological studies and mechanistic research into model systems, especially focusing on the interaction of different EDCs and the consequences of prenatal and early life exposure.

Desafíos a la epidemiología (pasos para una epidemiología "Miltoniana" Challenges to epidemiology (steps to a "Miltonian" epidemiology

Directory of Open Access Journals (Sweden)

Juan Samaja

2003-06-01

Full Text Available Se sostiene que uno de los grandes desafíos que enfrenta la Epidemiología contemporánea está situado en el campo teórico, y consiste esencialmente en la exigencia de revisar la conceptualización del objeto de la epidemiología dominante que reduce la salud de las poblaciones al comportamiento de los riesgos concebidos con abstracción de los vínculos particulares que los sujetos guardan con sus corporeidades geográficas y medioambientales. El artículo pretende reintroducir la perspectiva dialéctica que deja de lado la visión sustancialista de la realidad de las poblaciones de un lado y del medio ambiente, del otro lado, para proponer una visión estructural, funcional e histórica de ambos conceptos, desarrollando, en este sentido el espíritu de la obra del Gran Geógrafo Brasileiro.This paper argues that one of the major challenges that contemporary Epidemiology has to face is at the level of theory. In essence, it is necessary to revise the abstract conceptualization of the dominant Epidemiology object, which has reduced the health of the population to behavioral risks, without taking into account the link that people have to their geographical and environmental corporities. This article then seeks to reinsert the dialectical perspective that leaves aside the substantialist view of population reality, on one side, and that of the environment, on the other, in order to propose a structural, functional and historical perspective of both concepts, developing, in this way, the spirit of the Great Brazilian Geographer's work.

Assessment of HIV molecular surveillance capacity in the European Union, 2016.

Science.gov (United States)

Keating, Patrick; Pharris, Anastasia; Leitmeyer, Katrin; De Angelis, Stefania; Wensing, Annemarie; Amato-Gauci, Andrew J; Broberg, Eeva

2017-12-01

IntroductionExpanding access to HIV antiretroviral treatment is expected to decrease HIV incidence and acquired immunodeficiency syndrome (AIDS) mortality. However, this may also result in increased HIV drug resistance (DR). Better monitoring and surveillance of HIV DR is required to inform treatment regimens and maintain the long term effectiveness of antiretroviral drugs. As there is currently no formal European Union (EU)-wide collection of HIV DR data, this study aimed to assess the current HIV molecular surveillance capacity in EU/European Economic Area (EEA) countries in order to inform the planning of HIV DR monitoring at EU level. Methods: Thirty EU/EEA countries were invited to participate in a survey on HIV molecular surveillance capacity, which also included laboratory aspects. Results: Among 21 responding countries, 13 reported using HIV sequence data (subtype and/or DR) for surveillance purposes at national level. Of those, nine stated that clinical, epidemiological and sequence data were routinely linked for analysis. Discussion/conclusion : We identified similarities between existing HIV molecular surveillance systems, but also found important challenges including human resources, data ownership and legal issues that would need to be addressed.Information on capacities should allow better planning of the phased introduction of HIV DR surveillance at EU/EEA level.

The Vital Capacity Is Vital: Epidemiology and Clinical Significance of the Restrictive Spirometry Pattern.

Science.gov (United States)

Godfrey, Mark S; Jankowich, Matthew D

2016-01-01

Epidemiologic research has revealed a substantial portion of the general population with abnormal spirometry results that are characterized by decreased FEV1 and FVC but a preserved FEV1/FVC ratio. This restrictive spirometry pattern (RSP) is inconsistently defined in the literature and not well addressed by current guidelines; there is an accumulating body of evidence, however, that RSP is prevalent to a similar degree as airflow obstruction. Genetic and other risk factors for RSP, such as inhalational injuries and early life exposures, continue to be actively described. Although it seems that RSP is closely associated with the metabolic syndrome, diabetes, and systemic inflammation, it is not a simple marker of obesity. RSP is associated with adverse cardiovascular outcomes, as well as mortality, and it may be an underappreciated cause of functional impairments and respiratory symptoms. Improvement in outcomes in this population will require that clinicians have an appreciation for the significance of this spirometry pattern; additional research into the clinical and radiologic phenotype of these subjects is also needed. This article provides an overview of the recent developments in our understanding of this prevalent and highly morbid spirometry pattern. Published by Elsevier Inc.

An animated depiction of major depression epidemiology

Directory of Open Access Journals (Sweden)

Patten Scott B

2007-06-01

Full Text Available Abstract Background Epidemiologic estimates are now available for a variety of parameters related to major depression epidemiology (incidence, prevalence, etc.. These estimates are potentially useful for policy and planning purposes, but it is first necessary that they be synthesized into a coherent picture of the epidemiology of the condition. Several attempts to do so have been made using mathematical modeling procedures. However, this information is not easy to communicate to users of epidemiological data (clinicians, administrators, policy makers. Methods In this study, up-to-date data on major depression epidemiology were integrated using a discrete event simulation model. The mathematical model was animated in Virtual Reality Modeling Language (VRML to create a visual, rather than mathematical, depiction of the epidemiology. Results Consistent with existing literature, the model highlights potential advantages of population health strategies that emphasize access to effective long-term treatment. The paper contains a web-link to the animation. Conclusion Visual animation of epidemiological results may be an effective knowledge translation tool. In clinical practice, such animations could potentially assist with patient education and enhanced long-term compliance.

An animated depiction of major depression epidemiology.

Science.gov (United States)

Patten, Scott B

2007-06-08

Epidemiologic estimates are now available for a variety of parameters related to major depression epidemiology (incidence, prevalence, etc.). These estimates are potentially useful for policy and planning purposes, but it is first necessary that they be synthesized into a coherent picture of the epidemiology of the condition. Several attempts to do so have been made using mathematical modeling procedures. However, this information is not easy to communicate to users of epidemiological data (clinicians, administrators, policy makers). In this study, up-to-date data on major depression epidemiology were integrated using a discrete event simulation model. The mathematical model was animated in Virtual Reality Modeling Language (VRML) to create a visual, rather than mathematical, depiction of the epidemiology. Consistent with existing literature, the model highlights potential advantages of population health strategies that emphasize access to effective long-term treatment. The paper contains a web-link to the animation. Visual animation of epidemiological results may be an effective knowledge translation tool. In clinical practice, such animations could potentially assist with patient education and enhanced long-term compliance.

Cancer Epidemiology Data Repository (CEDR)

Science.gov (United States)

In an effort to broaden access and facilitate efficient data sharing, the Epidemiology and Genomics Research Program (EGRP) has created the Cancer Epidemiology Data Repository (CEDR), a centralized, controlled-access database, where Investigators can deposit individual-level de-identified observational cancer datasets.

Insecticide control of vector-borne diseases: when is insecticide resistance a problem?

Directory of Open Access Journals (Sweden)

Ana Rivero

Full Text Available Many of the most dangerous human diseases are transmitted by insect vectors. After decades of repeated insecticide use, all of these vector species have demonstrated the capacity to evolve resistance to insecticides. Insecticide resistance is generally considered to undermine control of vector-transmitted diseases because it increases the number of vectors that survive the insecticide treatment. Disease control failure, however, need not follow from vector control failure. Here, we review evidence that insecticide resistance may have an impact on the quality of vectors and, specifically, on three key determinants of parasite transmission: vector longevity, competence, and behaviour. We argue that, in some instances, insecticide resistance is likely to result in a decrease in vector longevity, a decrease in infectiousness, or in a change in behaviour, all of which will reduce the vectorial capacity of the insect. If this effect is sufficiently large, the impact of insecticide resistance on disease management may not be as detrimental as previously thought. In other instances, however, insecticide resistance may have the opposite effect, increasing the insect's vectorial capacity, which may lead to a dramatic increase in the transmission of the disease and even to a higher prevalence than in the absence of insecticides. Either way-and there may be no simple generality-the consequence of the evolution of insecticide resistance for disease ecology deserves additional attention.

Ophthalmic epidemiology in Europe

DEFF Research Database (Denmark)

Delcourt, Cécile; Korobelnik, Jean-François; Buitendijk, Gabriëlle H S

2016-01-01

The European Eye Epidemiology (E3) consortium is a recently formed consortium of 29 groups from 12 European countries. It already comprises 21 population-based studies and 20 other studies (case-control, cases only, randomized trials), providing ophthalmological data on approximately 170,000 Euro......The European Eye Epidemiology (E3) consortium is a recently formed consortium of 29 groups from 12 European countries. It already comprises 21 population-based studies and 20 other studies (case-control, cases only, randomized trials), providing ophthalmological data on approximately 170......,000 European participants. The aim of the consortium is to promote and sustain collaboration and sharing of data and knowledge in the field of ophthalmic epidemiology in Europe, with particular focus on the harmonization of methods for future research, estimation and projection of frequency and impact...

The evolving epidemiology of inflammatory bowel disease.

LENUS (Irish Health Repository)

Shanahan, Fergus

2009-07-01

Epidemiologic studies in inflammatory bowel disease (IBD) include assessments of disease burden and evolving patterns of disease presentation. Although it is hoped that sound epidemiologic studies provide aetiological clues, traditional risk factor-based epidemiology has provided limited insights into either Crohn\\'s disease or ulcerative colitis etiopathogenesis. In this update, we will summarize how the changing epidemiology of IBD associated with modernization can be reconciled with current concepts of disease mechanisms and will discuss studies of clinically significant comorbidity in IBD.

Epidemiología de la tripanosomiasis americana en el Norte de Corrientes Epidemiology of American trypanosomiasis in the North of Corrientes province, Argentina

Directory of Open Access Journals (Sweden)

María Esther Bar

2010-04-01

Full Text Available El objetivo de esta investigación fue evaluar la presencia de triatominos en ecotopos domésticos y extradomésticos, determinar el índice de infección de los triatominos y estimar la prevalencia humana de anticuerpos contra el Trypanosoma cruzi. Los muestreos se llevaron a cabo en viviendas seleccionadas al azar en áreas rurales (departamentos Mburucuyá en otoño 2007 y Berón de Astrada en verano 2008 de Corrientes, Argentina. El diagnóstico de la infección chagásica se realizó a voluntarios mediante las pruebas de hemaglutinación indirecta, inmunofluorescencia indirecta y ensayo inmunoenzimático. Se exploraron 32 viviendas y 33 peridomicilios en Mburucuyá, y 30 viviendas y 25 peridomicilios en Berón de Astrada. En Mburucuyá la infestación del peridomicilio por Triatoma sordida alcanzó un 3.0%, capturándose 19 ninfas en un gallinero. La infestación del peridomicilio en Berón de Astrada fue 4.0%, detectándose una hembra y 58 huevos en un nidal de ave. Tanto la hembra como las ninfas resultaron negativas al T. cruzi. La prevalencia de seropositivos humanos al T. cruzi fue 5.2% (4/77 en Mburucuyá y 14.3% (11/77 en Berón de Astrada. En el domicilio no se confirmó infestación por triatominos y en el peridomicilio el índice de infestación fue bajo. Es necesario implementar nuevas estrategias de control vectorial, especialmente para las especies que habitan en estructuras peridomésticas y biotopos silvestres. La seroprevalencia fue menor a la observada en investigaciones previas en las áreas rurales de Corrientes. La ausencia de seropositivos de 0-10 años indica que la transmisión vectorial está interrumpida.The aim of this investigation was to evaluate triatomine colonization in domestic and extradomestic ecotopes, to determine triatomines infection index and to assess human prevalence of anti Trypanosoma cruzi antibodies at Berón de Astrada and Mburucuyá Departments, Corrientes, Argentina. Samplings were performed

Epidemiological methods: a brief review

International Nuclear Information System (INIS)

Winkelstein, W. Jr.

1983-01-01

Epidemiology, the study of disease distributions in populations and the factors which influence these distributions, is an observational science, i.e., its data base consists of measurements made on free living individuals characterized by presence or absence of disease states and putative risk factors. Epidemiological studies are usually classified as descriptive or analytical. Descriptive studies are primarily used for planning and evaluating health programs or to generate etiological hypotheses. Analytical studies are primarily used for testing etiological hypotheses. Analytical studies are designed either as cohort investigations in which populations with and without a putative risk factor are followed through time to ascertain their differential incidence of disease, or case-control investigations in which the history of exposure to a putative risk factor is compared among persons with a disease and appropriate controls free of disease. Both descriptive and analytical epidemiological studies have been applied to health physics problems. Examples of such problems and the epidemiological methods used to explore them will be presented

Prediction of temperature and damage in an irradiated human eye-Utilization of a detailed computer model which includes a vectorial blood stream in the choroid.

Science.gov (United States)

Heussner, Nico; Holl, Lukas; Nowak, Timo; Beuth, Thorsten; Spitzer, Martin S; Stork, Wilhelm

2014-08-01

The work presented here describes the development and use of a three-dimensional thermo-dynamic model of the human eye for the prediction of temperatures and damage thresholds under irradiation. This model takes into account the blood flow by the implementation of a vectorial blood stream in the choroid and also uses the actual physiological extensions and tissue parameters of the eye. Furthermore it considers evaporation, radiation and convection at the cornea as well as the eye lid. The predicted temperatures were successfully validated against existing eye models in terms of corneal and global thermal behaviour. The model׳s predictions were additionally checked for consistency with in-vivo temperature measurements of the cornea, the irradiated retina and its damage thresholds. These thresholds were calculated from the retinal temperatures using the Arrhenius integral. Hence the model can be used to predict the temperature increase and irradiation hazard within the human eye as long as the absorption values and the Arrhenius coefficients are known and the damage mechanism is in the thermal regime. Copyright © 2014 Elsevier Ltd. All rights reserved.

Radiation carcinogenesis: Epidemiology and biological significance

International Nuclear Information System (INIS)

Boice, J.D.; Fraumeni, J.F.

1984-01-01

Epidemiologic studies of populations exposed to radiation have led to the identification of a preventable cause of cancer, but in the long run perhaps the most important contribution of radiation studies will be to provide insights into the basic processes of human carcinogenesis. In this volume, key investigators of major epidemiologic projects summarize their observations to date, including information to help assess the effects of low-level exposures. Experimentalists and theorists emphasize the relevance of laboratory and epidemiologic data in elucidating carcinogenic risks and mechanisms in man. This volume was prepared with several objectives in mind: (a) organize and synthesize knowledge on radiation carcinogenesis through epidemiologic and experimental approaches; (b) illustrate and explore ways of utilizing this information to gain insights into the fundamental mechanisms of cancer development; (c) stimulate the formation of hypotheses suited to experimental or epidemiologic testing, theoretical modeling, and multidisciplinary approaches; and (d) identify recent advances that clarify dose-response relationships and the influence of low-dose exposures, provide leads to carcinogenic mechanisms and host-environmental interactions, and suggest strategies for future research and preventive action

The science of epidemiology and the methods needed for public health assessments: a review of epidemiology textbooks.

Science.gov (United States)

Gouda, Hebe N; Powles, John W

2014-02-10

Epidemiology is often described as 'the science of public health'. Here we aim to assess the extent that epidemiological methods, as covered in contemporary standard textbooks, provide tools that can assess the relative magnitude of public health problems and can be used to help rank and assess public health priorities. Narrative literature review. Thirty textbooks were grouped into three categories; pure, extended or applied epidemiology, were reviewed with attention to the ways the discipline is characterised and the nature of the analytical methods described. Pure texts tend to present a strict hierarchy of methods with those metrics deemed to best serve aetiological inquiry at the top. Extended and applied texts employ broader definitions of epidemiology but in most cases, the metrics described are also those used in aetiological inquiry and may not be optimal for capturing the consequences and social importance of injuries and disease onsets. The primary scientific purpose of epidemiology, even amongst 'applied' textbooks, is aetiological inquiry. Authors do not readily extend to methods suitable for assessing public health problems and priorities.

Mitochondrial DNA and Cancer Epidemiology Workshop

Science.gov (United States)

A workshop to review the state-of-the science in the mitochondrial DNA field and its use in cancer epidemiology, and to develop a concept for a research initiative on mitochondrial DNA and cancer epidemiology.

Radiation epidemiology: Past and present

International Nuclear Information System (INIS)

Boice, J.D. Jr.

1997-01-01

Major advancements in radiation epidemiology have occurred during the last several years in studies of atomic bomb survivors, patients given medical radiation, and radiation workers, including underground miners. Risks associated with the Chernobyl accident, indoor radon and childhood exposure to I-131 have yet to be elucidated. Situations in the former Soviet Union around Chelyabinsk, a nuclear installation in the southern Urals, and in the Altai, which received radioactive fallout from weapons testing at Semipalatinsk, Kazakhstan, have the potential to provide information on the effects of chronic radiation exposure. Since Roentgen's discovery of x-rays just 100 years ago, a tremendous amount of knowledge has been accumulated about human health effects following irradiation. The 1994 UNSCEAR report contains the latest compilation and synthesis of radiation epidemiology. This overview will cover epidemiology from a radiation perspective. The different types of study methodologies will be described, followed by a kaleidoscope coverage of past and present studies; ending with some remaining questions in radiation epidemiology. This should set the stage for future chapters, and stimulate thinking about implications of the new data on radiation cancer risks

Translational Epidemiology in Psychiatry

Science.gov (United States)

Weissman, Myrna M.; Brown, Alan S.; Talati, Ardesheer

2012-01-01

Translational research generally refers to the application of knowledge generated by advances in basic sciences research translated into new approaches for diagnosis, prevention, and treatment of disease. This direction is called bench-to-bedside. Psychiatry has similarly emphasized the basic sciences as the starting point of translational research. This article introduces the term translational epidemiology for psychiatry research as a bidirectional concept in which the knowledge generated from the bedside or the population can also be translated to the benches of laboratory science. Epidemiologic studies are primarily observational but can generate representative samples, novel designs, and hypotheses that can be translated into more tractable experimental approaches in the clinical and basic sciences. This bedside-to-bench concept has not been explicated in psychiatry, although there are an increasing number of examples in the research literature. This article describes selected epidemiologic designs, providing examples and opportunities for translational research from community surveys and prospective, birth cohort, and family-based designs. Rapid developments in informatics, emphases on large sample collection for genetic and biomarker studies, and interest in personalized medicine—which requires information on relative and absolute risk factors—make this topic timely. The approach described has implications for providing fresh metaphors to communicate complex issues in interdisciplinary collaborations and for training in epidemiology and other sciences in psychiatry. PMID:21646577

Maritim epidemiologi på Supercourse

DEFF Research Database (Denmark)

Jensen, Olaf

2015-01-01

Maritim epidemiologi er nu kommet med i samlingen af undervisningsmidler på ”Supercourse”. Der er oprettet en særlig mappe med Maritime Epidemiology og alle der har gode bidrag inden for området opfordres hermed til at publicere her. Supercourse er en samling af foredrag beregnet til at være en r...

Snippets from the past: the evolution of Wade Hampton Frost's epidemiology as viewed from the American Journal of Hygiene/Epidemiology.

Science.gov (United States)

Morabia, Alfredo

2013-10-01

Wade Hampton Frost, who was a Professor of Epidemiology at Johns Hopkins University from 1919 to 1938, spurred the development of epidemiologic methods. His 6 publications in the American Journal of Hygiene, which later became the American Journal of Epidemiology, comprise a 1928 Cutter lecture on a theory of epidemics, a survey-based study of tonsillectomy and immunity to Corynebacterium diphtheriae (1931), 2 papers from a longitudinal study of the incidence of minor respiratory diseases (1933 and 1935), an attack rate ratio analysis of the decline of diphtheria in Baltimore (1936), and a 1936 lecture on the age, time, and cohort analysis of tuberculosis mortality. These 6 American Journal of Hygiene /American Journal of Epidemiology papers attest that Frost's personal evolution mirrored that of the emerging "early" epidemiology: The scope of epidemiology extended beyond the study of epidemics of acute infectious diseases, and rigorous comparative study designs and their associated quantitative methods came to light.

Complex dynamics of an eco-epidemiological model with different competition coefficients and weak Allee in the predator

International Nuclear Information System (INIS)

Saifuddin, Md.; Biswas, Santanu; Samanta, Sudip; Sarkar, Susmita; Chattopadhyay, Joydev

2016-01-01

The paper explores an eco-epidemiological model with weak Allee in predator, and the disease in the prey population. We consider a predator-prey model with type II functional response. The curiosity of this paper is to consider different competition coefficients within the prey population, which leads to the emergent carrying capacity. We perform the local and global stability analysis of the equilibrium points and the Hopf bifurcation analysis around the endemic equilibrium point. Further we pay attention to the chaotic dynamics which is produced by disease. Our numerical simulations reveal that the three species eco-epidemiological system without weak-Allee induced chaos from stable focus for increasing the force of infection, whereas in the presence of the weak-Allee effect, it exhibits stable solution. We conclude that chaotic dynamics can be controlled by the Allee parameter as well as the competition coefficients. We apply basic tools of non-linear dynamics such as Poincare section and maximum Lyapunov exponent to identify chaotic behavior of the system.

The Training of Epidemiologists and Diversity in Epidemiology: Findings from the 2006 Congress of Epidemiology Survey

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Carter-Pokras, Olivia D.; Spirtas, Robert; Bethune, Lisa; Mays, Vickie; Freeman, Vincent L.; Cozier, Yvette C.

2013-01-01

Purpose In the past decade, we have witnessed increasing numbers of individuals entering the field of epidemiology. With the increase also has come a diversity of training and paths by which individuals entered the field. The purpose of this survey was characterization of the epidemiology workforce, its job diversity, and continuing education needs. Methods The Minority Affairs and Membership committees of the American College of Epidemiology (ACE) prepared and administered a workforce survey to identify racial/ethnic diversity, demographic background, workplace type, credentials, income, subspecialties, and continuing education needs of epidemiologists. The survey was self-administered to attendees of the Second North American Congress of Epidemiology in June 2006. Results A sample of 397 respondents of the 1348 registered for the Congress was captured (29.5% response). Epidemiologists who participated were from 36 states and 18 countries; 54.6% were trained at the doctoral level; 19.1% earned $120,001 or more a year. A wide range of epidemiology subspecialties and continuing education needs were identified. Conclusions This preliminary snapshot of epidemiologists indicates a wide range of training mechanisms, workplace sites, and subspecialties. Results indicate a need for examination of the core graduate training needs of epidemiologist as well as responding to desired professional development needs through the provision of continuing educations efforts. PMID:19344867

Culicoides and the global epidemiology of bluetongue virus infection.

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Tabachnick, W J

2004-01-01

The distribution of the bluetongue viruses (BTV) is limited to geographic areas containing competent vector species. All BTV-competent species belong to the genus Culicoides. In the New World, two different BTV epidemiological systems (episystems) occur. Culicoides sonorensis is responsible for transmitting BTV serotypes in North America that differ from South American serotypes transmitted by C. insignis. There are other episystems in the world. The role of different Culicoides vector species and the underlying mechanisms governing their vector capacity for BTV are unknown. It is likely that these vary between Culicoides species and episystems. As a result, our ability to predict and/or mitigate BTV in different episystems will remain problematic. Several complex issues need to be resolved to provide risk assessment and mitigation for BTV. This will require a substantial investment in new research paradigms that investigate details of underlying controlling mechanisms in several species of Culicoides.

Natural phenolic antioxidants in human fluids: analytical approaches and antioxidant capacity studies

International Nuclear Information System (INIS)

Zhang, K.; Zuo, Y.

2006-01-01

Phenolic compounds are the most abundant natural antioxidants in our diet. Epidemiological studies have shown the possible prevention effects of consumption of fruits and vegetables rich in phenolic compounds on degenerative diseases, such as cardiovascular diseases and cancers. However, there is a serious lack of fundamental knowledge on the uptake and metabolism of phenolic compounds in humans. It is clear that phenolic molecules, only absorbed by humans, can exert biological effects. This review presents a current knowledge on the analytical methods, antioxidant capacity measurements, as well as research strategies related to natural phenolic antioxidants on human health. Both GC-MS and LC-MS have proved to be very useful analytical techniques that can be employed to identify and quantitate targeted phenolic antioxidants and their metabolites in biofluids. Free radical quenching tests provide a direct measurement of antioxidant capacity but lack specificity and may oversimplify the in vivo human physiological environment. Research strategies are diverse and mainly focused on positive health effect of antioxidants. In the future studies, multiple potential bioactivities, both positive and negative, should be considered. (author)

Advances in radiation epidemiology

International Nuclear Information System (INIS)

Boice, J.

1997-01-01

The 1994 UNSCEAR report provides an informative review of radiation epidemiology. During the past 2 years there have been several major advances in our understanding of radiation effects based on new studies of atomic bomb survivors in Japan, of patients given diagnostic and therapeutic radiation (including iodine-131), of workers occupationally exposed, and of general populations exposed to residential radon. Laboratory approaches are also being incorporated into epidemiological investigations to learn more about the biological mechanism by which radiation causes cancer in man. (author)

Complex epidemiological approach to human mutagenesis

International Nuclear Information System (INIS)

Czeizel, A.

1980-01-01

The main characteristics of the epidemiological approach are summarised and the criteria discussed for the adoption of this approach for the detection of human mutagenesis. Mutation monitoring systems are described and results of epidemiological studies of higher risk populations are presented. (C.F.)

Retrospective study of epidemiological, clinicopathological and ...

African Journals Online (AJOL)

Retrospective study of epidemiological, clinicopathological and biological profils of 62 colorectal cancers cases in Jijel provence (Algeria) ... Our results were often compatible with the available literature and may provide reliable and relevant data on this disease. Key words: Colorectal cancer; Epidemiology; Therapy; ...

Salmonella epidemiology: A whirlwind of change.

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Besser, John M

2018-05-01

The field of infectious disease epidemiology for Salmonella and other enteric pathogens is undergoing some of the most profound changes since the time of Kauffman and White. Rapid advances in "big data" technologies such as genomics and metagenomics are making it possible to monitor and control salmonellosis in new and exciting ways. Epidemiological methods are becoming increasingly robust through the routine use of standardized hypothesis-generating questionnaires, iterative open-ended interviewing, informational trace-backs and new modeling techniques for describing the attribution of disease to food sources. In addition, Salmonella epidemiology is facing important challenges and new opportunities due to the rapid adoption of culture independent diagnostic test panels by clinical laboratories. Where is this unprecedented wave of change taking us? This chapter will examine emerging trends in Salmonella epidemiology, and take a peek into the not-so-distant future. Published by Elsevier Ltd.

[Occupational epidemiology: some methodological considerations].

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Alvear-Galindo, María Guadalupe; del Pilar Paz-Román, María

2006-01-01

During the last decade, occupational epidemiology has gained a great importance, not only because of the increase of pollutants and their noxiousness, but also because it has gone from the descriptive to the analytic level. The purpose of this work is to present what has been reported on epidemiological studies, different ways of characterizing and measuring occupational exposure, by emphasizing slants of exposure and selection measurement. In the reviewed studies, an interest in improving the exposure evaluation has been shown. The mainly reported measurement slants are the ways of measuring and classifying the exposure. The main designs were transversal with the use of matrixes to improve the evaluation of exposure. Conditions of hygiene and security were considered in order to control the quality of the information. This information was analyzed with different criteria. Some of the elements that hinder the research on occupational epidemiology are a mixed exposure, small populations, lack of exposure data, low levels of exposure and long periods of illness latency. Some breakthroughs in the strategies of epidemiological analysis and some other areas of knowledge have made possible a better understanding of work and health conditions of workers.

Descriptive and analytic epidemiology. Bridges to cancer control

International Nuclear Information System (INIS)

Mettlin, C.

1988-01-01

Epidemiology serves as a bridge between basic science and cancer control. The two major orientations of epidemiology are descriptive and analytic. The former is useful in assessing the scope and dimensions of the cancer problem and the latter is used to assess environmental and lifestyle sources of cancer risk. A recent development in descriptive epidemiology is the use of functional measures of disease such as lost life expectancy. In analytical epidemiology, there is new or renewed interest in several lifestyle factors including diet and exercise as well as environmental factors such as involuntary tobacco exposure and radon in dwellings. Review of the evidence should consider the strengths and weaknesses of different research procedures. Each method is inconclusive by itself but, the different research designs of epidemiology collectively may represent a hierarchy of proof. Although the roles of many factors remain to be defined, the aggregate epidemiologic data continue to demonstrate the special importance of personal behavior and lifestyle in affecting cancer risk

Epidemiology in Germany-general development and personal experience.

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Wichmann, Heinz-Erich

2017-08-01

Did you ever hear about epidemiology in Germany? Starting from an epidemiological desert the discipline has grown remarkably, especially during the last 10-15 years: research institutes have been established, research funding has improved, multiple curriculae in Epidemiology and Public Health are offered. This increase has been quite steep, and now the epidemiological infrastructure is much better. Several medium-sized and even big population cohorts are ongoing, and the number and quality of publications from German epidemiologists has reached a respectable level. My own career in epidemiology started in the field of environmental health. After German reunification I concentrated for many years on environmental problems in East Germany and observed the health benefits after improvement of the situation. Later, I concentrated on population-based cohorts in newborns (GINI/LISA) and adults (KORA, German National Cohort), and on biobanking. This Essay describes the development in Germany after worldwar 2, illustrated by examples of research results and build-up of epidemiological infractructures worth mentioning.

La epidemiología ocupacional como herramienta básica para la salud de los trabajadores Occupational epidemiology as a basic tool for workers' health

Directory of Open Access Journals (Sweden)

Caristina Robaina Aguirre

2006-06-01

Full Text Available Se realizó un pequeño bosquejo del desarrollo de la Epidemiología como ciencia y su importancia en salud pública en general. Se transita por las definiciones de vieja y nueva epidemiología, de enfermedades crónicas, transmisibles y no transmisibles, del concepto de epidemiología social, etc. para posteriormente hablar de la importancia de la Epidemiología Ocupacional en la Salud PúblicaA review of the development of Epidemiology as a science, and its significance in public health in general, was made. The old and new definitions of epidemiology, of chronic, transmissible and non-transmissible diseases, of social epidemiology concept, etc., are analysed to further deal with the importance of Occupational Epidemiology in Public Health.

Epidemiological issues related to dose reconstruction

International Nuclear Information System (INIS)

Shore, R.E.

1996-01-01

When a dose reconstruction is performed around some nuclear site, a decision has to be made as to whether an epidemiologic study should be performed there and, if so, what form the study should take. The goal of this paper is to provide an overview of epidemiologic and biostatistical issues that help determine whether an epidemiologic study around a nuclear facility is worthwhile doing from a scientific standpoint. We are all aware that public health and sociopolitical concerns often assume considerable importance in these decisions, but they will not be considered here. 27 refs., 2 tabs

Nuclear accidents and epidemiology

International Nuclear Information System (INIS)

1987-01-01

A consultation on epidemiology related to the Chernobyl accident was held in Copenhagen in May 1987 as a basis for concerted action. This was followed by a joint IAEA/WHO workshop in Vienna, which reviewed appropriate methodologies for possible long-term effects of radiation following nuclear accidents. The reports of these two meetings are included in this volume, and cover the subjects: 1) Epidemiology related to the Chernobyl nuclear accident. 2) Appropriate methodologies for studying possible long-term effects of radiation on individuals exposed in a nuclear accident. Figs and tabs

Bionomics and vectorial capacity of Anopheles annularis with special reference to India: a review.

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Singh, R K; Haq, S; Kumar, Gaurav; Dhiman, R C

2013-01-01

Anopheles annularis is widely distributed mosquito species all over the country. An. annularis has been incriminated as a malaria vector in India, Sri Lanka, Bangladesh, Myanmar, Indonesia, Malaysia and China. In India, it has been reported to play an important role in malaria transmission as a secondary vector in certain parts of Assam, West Bengal and U.P. In Odisha and some neighbouring countries such as Sri Lanka, Nepal and Myanmar it has been recognised as a primary vector of malaria. This is a species complex of two sibling species A and B but the role of these sibling species in malaria transmission is not clearly known. An. annularis is resistant to DDT and dieldrin/HCH and susceptible to malathion and synthetic pyrethorides in most of the parts of India. In view of rapid change in ecological conditions, further studies are required on the bionomics of An. annularis and its role in malaria transmission in other parts of the country. Considering the importance of An. annularis as a malaria vector, the bionomics and its role in malaria transmission has been reviewed in this paper. In this communication, an attempt has been made to review its bionomics and its role as malaria vector. An. annularis is a competent vector of malaria, thus, due attention should be paid for its control under the vector control programmes specially in border states where it is playing a primary role in malaria transmission.

Cancer Epidemiology Cohorts

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Cohort studies are fundamental for epidemiological research by helping researchers better understand the etiology of cancer and provide insights into the key determinants of this disease and its outcomes.

A research agenda for malaria eradication: vector control.

Science.gov (United States)

2011-01-25

Different challenges are presented by the variety of malaria transmission environments present in the world today. In each setting, improved control for reduction of morbidity is a necessary first step towards the long-range goal of malaria eradication and a priority for regions where the disease burden is high. For many geographic areas where transmission rates are low to moderate, sustained and well-managed application of currently available tools may be sufficient to achieve local elimination. The research needs for these areas will be to sustain and perhaps improve the effectiveness of currently available tools. For other low-to-moderate transmission regions, notably areas where the vectors exhibit behaviours such as outdoor feeding and resting that are not well targeted by current strategies, new interventions that target predictable features of the biology/ecologies of the local vectors will be required. To achieve elimination in areas where high levels of transmission are sustained by very efficient vector species, radically new interventions that significantly reduce the vectorial capacity of wild populations will be needed. Ideally, such interventions should be implemented with a one-time application with a long-lasting impact, such as genetic modification of the vectorial capacity of the wild vector population.

About the Epidemiology and Genomics Research Program

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Epidemiology is the scientific study of the causes and distribution of disease in populations. NCI-funded epidemiology research is conducted through research at institutions in the United States and internationally.

LA REGLA DE CRAMER A PARTIR DEL PRODUCTO GENERALIZADO EN ℜn

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Moisés Aranda Silva

2003-12-01

Full Text Available En el espacio vectorial euclídeo ℜ3 se definen el producto vectorial y el producto triple, a partir de la interpretación geométrica de estos productos, definimos el producto vectorial en los espacios vectorialesℜ2, ℜ4 y ℜn. Con el producto vectorial generalizado se presenta una deducción elemental de la regla de Cramer.

The globalization of epidemiology: introductory remarks.

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Pearce, Neil

2004-10-01

We are all living in the era of globalization, and like it or not, it is going to change the way we practice epidemiology, the kinds of questions we ask, and the methods we use to answer them. Increasingly, pubic health problems are being shifted from rich countries to poor countries and from rich to poor populations within Western countries. There is increasing interest and concern about the situation in non-Western populations on the part of Western epidemiologists, with regards to collaborative research, skills transfer, and 'volunteerism' to enable the 'benefits' of Western approaches to epidemiology to be shared by the non-Western world. However, most existing collaborations benefit Western epidemiologists rather than the countries in which the research is conducted. Even when research in non-Western populations is conducted as a genuine collaboration, it can too often 'export failure' from the West. On the other hand, non-Western epidemiologists are increasingly developing new and innovative approaches to health research that are more appropriate to the global public health issues they are addressing. These include recognition of the importance of context and the importance of diversity and local knowledge, and a problem-based approach to addressing the major public health problems using appropriate technology. These debates formed the background for a plenary session on 'International Epidemiology and International Health' at the recent International Epidemiological Association (IEA) meeting in Montreal, and the papers from this session are presented here. The development of a truly global epidemiology can not only better address the public health problems in non-Western populations, but can shed light on the current limitations of epidemiology in addressing the major public health problems in the West.

Methodological exploratory study applied to occupational epidemiology

Energy Technology Data Exchange (ETDEWEB)

Carneiro, Janete C.G. Gaburo; Vasques, MOnica Heloisa B.; Fontinele, Ricardo S.; Sordi, Gian Maria A. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mail: janetegc@ipen.br

2007-07-01

The utilization of epidemiologic methods and techniques has been object of practical experimentation and theoretical-methodological reflection in health planning and programming process. Occupational Epidemiology is the study of the causes and prevention of diseases and injuries from exposition and risks in the work environment. In this context, there is no intention to deplete such a complex theme but to deal with basic concepts of Occupational Epidemiology, presenting the main characteristics of the analysis methods used in epidemiology, as investigate the possible determinants of exposition (chemical, physical and biological agents). For this study, the social-demographic profile of the IPEN-CNEN/SP work force was used. The knowledge of this reference population composition is based on sex, age, educational level, marital status and different occupations, aiming to know the relation between the health aggravating factors and these variables. The methodology used refers to a non-experimental research based on a theoretical methodological practice. The work performed has an exploratory character, aiming a later survey of indicators in the health area in order to analyze possible correlations related to epidemiologic issues. (author)

Methodological exploratory study applied to occupational epidemiology

International Nuclear Information System (INIS)

Carneiro, Janete C.G. Gaburo; Vasques, MOnica Heloisa B.; Fontinele, Ricardo S.; Sordi, Gian Maria A.

2007-01-01

The utilization of epidemiologic methods and techniques has been object of practical experimentation and theoretical-methodological reflection in health planning and programming process. Occupational Epidemiology is the study of the causes and prevention of diseases and injuries from exposition and risks in the work environment. In this context, there is no intention to deplete such a complex theme but to deal with basic concepts of Occupational Epidemiology, presenting the main characteristics of the analysis methods used in epidemiology, as investigate the possible determinants of exposition (chemical, physical and biological agents). For this study, the social-demographic profile of the IPEN-CNEN/SP work force was used. The knowledge of this reference population composition is based on sex, age, educational level, marital status and different occupations, aiming to know the relation between the health aggravating factors and these variables. The methodology used refers to a non-experimental research based on a theoretical methodological practice. The work performed has an exploratory character, aiming a later survey of indicators in the health area in order to analyze possible correlations related to epidemiologic issues. (author)

Use of geoprocessing to define malaria risk areas and evaluation of the vectorial importance of anopheline mosquitoes (Diptera: Culicidae) in Espírito Santo, Brazil.

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Meneguzzi, Viviane Coutinho; Santos, Claudiney Biral dos; Pinto, Israel de Souza; Feitoza, Leandro Roberto; Feitoza, Hideko Nagatani; Falqueto, Aloísio

2009-07-01

In Brazil, introduced malaria occurs from the flat to the sloping hot areas, predominantly outside the Amazon Region, where endemic malaria has occurred in the past. This is a consequence of human migrations to other Brazilian states, including the state of Espírito Santo (ES). The objective of this study was to use geoprocessing to define the areas at risk of introduced malaria transmission and evaluate the vectorial importance of species of anophelines in ES. Anophelines were sampled from 1997-2005 in 297 rural localities identified or not identified as foci of malaria during the last 20 years. The geoclimatic variables temperature, relief and marine influence were obtained from a database of the ES Natural Units. The 14,663 anophelines captured belonged to 22 species. A significant association was found between the occurrence of malaria foci and the presence of hot, low-lying areas or gently undulating to undulating relief. The occurrence of the disease was associated with the presence of Anopheles darlingi and Anopheles aquasalis. Geoprocessing was determined to be a useful tool for defining areas at risk for malaria and vectors in ES.

[Implementation of the International Health Regulations in Cuba: evaluation of basic capacities of the health sector in selected provinces].

Science.gov (United States)

Gala, Ángela; Toledo, María Eugenia; Arias, Yanisnubia; Díaz González, Manuel; Alvarez Valdez, Angel Manuel; Estévez, Gonzalo; Abreu, Rolando Miyar; Flores, Gustavo Kourí

2012-09-01

Obtain baseline information on the status of the basic capacities of the health sector at the local, municipal, and provincial levels in order to facilitate identification of priorities and guide public policies that aim to comply with the requirements and capacities established in Annex 1A of the International Health Regulations 2005 (IHR-2005). A descriptive cross-sectional study was conducted by application of an instrument of evaluation of basic capacities referring to legal and institutional autonomy, the surveillance and research process, and the response to health emergencies in 36 entities involved in international sanitary control at the local, municipal, and provincial levels in the provinces of Havana, Cienfuegos, and Santiago de Cuba. The polyclinics and provincial centers of health and epidemiology in the three provinces had more than 75% of the basic capacities required. Twelve out of 36 units had implemented 50% of the legal and institutional framework. There was variable availability of routine surveillance and research, whereas the entities in Havana had more than 40% of the basic capacities in the area of events response. The provinces evaluated have integrated the basic capacities that will allow implementation of IHR-2005 within the period established by the World Health Organization. It is necessary to develop and establish effective action plans to consolidate surveillance as an essential activity of national and international security in terms of public health.

Entomologic considerations in the study of onchocerciasis transmission.

Science.gov (United States)

Vargas, L; Díaz-Nájera, A

1980-01-01

The entomological resources utilized for a better understanding of Onchocerca volvulus transmission are discussed in this paper. Vector density, anthropohilia, gonotrophic cycyle, parous condition longevity and probability of survival in days after the infectious meal are assessed here in order to integrate an overall picture. The concept of vectorial capacity is developed stressing the quantitative aspects. Parasitism of the black-flies by filariae that are doubtfully identified as O. volvulus is also mentioned here.

Description and Comparison of Morphological Structures of the Eggs of Anopheles Hyrcanus Group and Related Species (Diptera: Culicidae) from the Republic of Korea

Science.gov (United States)

2009-10-20

major vector of malaria in China ; however, its vectorial capacity is unknown in the ROK. The other remaining four Anopheles species are not considered to...morphometry and morphology of Anopheles aconitus Form B and C eggs under scanning electron microscope. Revista do Instituto de Medicina Tropical de Sao Paulo...and its genetic identity with An. (Ano.) anthropophagus from China (Diptera: Culicidae). Zootaxa, 378, 1–14. RUEDA ET AL.40 · Zootaxa 2268 © 2009

Epidemiology of Schizophrenia: Review of Findings and Myths

OpenAIRE

Messias, Erick; Chen, Chuan-Yu; Eaton, William W.

2007-01-01

By describing patterns of disease distribution within populations, identifying risk factors, and finding associations, epidemiological studies have contributed to our current understanding of schizophrenia. Advanced paternal age and the association with auto-immune diseases are some of the newly described epidemiological finding in schizophrenia epidemiology, shaping our current definition of schizophrenia. Though early intervention strategies have gained momentum, primary prevention of schiz...

Influência das características sociodemográficas e epidemiológicas na capacidade funcional de idosos residentes em Ubá, Minas Gerais The influence of sociodemographic and epidemiological characteristics on the functional capacity of elderly residents in the city of Ubá, Minas Gerais

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Maria Célia R. Nunes

2009-10-01

individuals. The functional capacity was assessed by means of the scale of basic and instrumental activities of daily living. The associations between functional capacity and socioeconomic, demographic and epidemiological characteristics were investigated. Data were analyzed with the softwares Epi Info version 6.0 and SigmaStat. A significance level of 0.05 was considered. For statistical analysis, frequency distribution and measures of association (odds ratio were performed between the functional capacity and the socioeconomic, demographic and epidemiological variables. Multiple logistic regression analysis was conducted. RESULTS: The impaired functional capacity was related to self-referred deteriorated health conditions, falls, female gender, widowhood, more advanced age, low educational level and income, and retirement from the job market. CONCLUSION: The lack of integral health care for the elderly, especially those without financial resources, can contribute negatively to worsened health conditions, especially functional capacity.

Anopheles culicifacies sibling species in Odisha, eastern India: First appearance of Anopheles culicifacies E and its vectorial role in malaria transmission.

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Das, Mumani; Das, Biswadeep; Patra, Aparna P; Tripathy, Hare K; Mohapatra, Namita; Kar, Santanu K; Hazra, Rupenangshu K

2013-07-01

To identify the Anopheles culicifacies sibling species complex and study their vectorial role in malaria endemic regions of Odisha. Mosquitoes were collected from 6 malaria endemic districts using standard entomological collection methods. An. culicifacies sibling species were identified by multiplex polymerase chain reaction (PCR) using cytochrome oxidase subunit II (COII) region of mitochondrial DNA. Plasmodium falciparum (Pf) sporozoite rate and human blood fed percentage (HBF) were estimated by PCR using Pf- and human-specific primers. Sequencing and phylogenetic analysis were performed to confirm the type of sibling species of An. culicifacies found in Odisha. Multiplex PCR detected An. culicifacies sibling species A, B, C, D and E in the malaria endemic regions of Odisha. An. culicifacies E was detected for the first time in Odisha, which was further confirmed by molecular phylogenetics. Highest sporozoite rate and HBF percentage were observed in An. culicifacies E in comparison with other sibling species. An. culicifacies E collected from Nawarangapur, Nuapara and Keonjhar district showed high HBF percentage and sporozoite rates. An. culicifacies B was the most abundant species, followed by An. culicifacies C and E. High sporozoite rate and HBF of An. culicifacies E indicated that it plays an important role in malaria transmission in Odisha. Appropriate control measures against An. culicifacies E at an early stage are needed to prevent further malaria transmission in Odisha. © 2013 Blackwell Publishing Ltd.

Acoustic communication in insect disease vectors

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Felipe de Mello Vigoder

2013-01-01

Full Text Available Acoustic signalling has been extensively studied in insect species, which has led to a better understanding of sexual communication, sexual selection and modes of speciation. The significance of acoustic signals for a blood-sucking insect was first reported in the XIX century by Christopher Johnston, studying the hearing organs of mosquitoes, but has received relatively little attention in other disease vectors until recently. Acoustic signals are often associated with mating behaviour and sexual selection and changes in signalling can lead to rapid evolutionary divergence and may ultimately contribute to the process of speciation. Songs can also have implications for the success of novel methods of disease control such as determining the mating competitiveness of modified insects used for mass-release control programs. Species-specific sound “signatures” may help identify incipient species within species complexes that may be of epidemiological significance, e.g. of higher vectorial capacity, thereby enabling the application of more focussed control measures to optimise the reduction of pathogen transmission. Although the study of acoustic communication in insect vectors has been relatively limited, this review of research demonstrates their value as models for understanding both the functional and evolutionary significance of acoustic communication in insects.

Emerging arthropod-borne diseases of companion animals in Europe.

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Beugnet, Frederic; Marié, Jean-Lou

2009-08-26

Vector-borne diseases are caused by parasites, bacteria or viruses transmitted by the bite of hematophagous arthropods (mainly ticks and mosquitoes). The past few years have seen the emergence of new diseases, or re-emergence of existing ones, usually with changes in their epidemiology (i.e. geographical distribution, prevalence, and pathogenicity). The frequency of some vector-borne diseases of pets is increasing in Europe, i.e. canine babesiosis, granulocytic anaplasmosis, canine monocytic ehrlichiosis, thrombocytic anaplasmosis, and leishmaniosis. Except for the last, these diseases are transmitted by ticks. Both the distribution and abundance of the three main tick species, Rhipicephalus sanguineus, Dermacentor reticulatus and Ixodes ricinus are changing. The conditions for such changes involve primarily human factors, such as travel with pets, changes in human habitats, social and leisure activities, but climate changes also have a direct impact on arthropod vectors (abundance, geographical distribution, and vectorial capacity). Besides the most known diseases, attention should be kept on tick-borne encephalitis, which seems to be increasing in western Europe, as well as flea-borne diseases like the flea-transmitted rickettsiosis. Here, after consideration of the main reasons for changes in tick vector ecology, an overview of each "emerging" vector-borne diseases of pets is presented.

Occupational reproductive epidemiology: Pt. 1

International Nuclear Information System (INIS)

Roman, Eve; Doyle, Pat

1993-01-01

The authors review the current state of knowledge about possible adverse effects of hazardous paternal workplace exposures on human reproduction is scant. The methodology for studying possible association between occupational exposures and adverse reproductive events is not well developed. More detailed laboratory and epidemiological research is clearly required, and better collaboration between these two disciplines is needed. Associations suggested in the course of epidemiological research need to be tested in the laboratory, and vice versa. (author)

Epidemiology of idiopathic pulmonary fibrosis

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Ley B

2013-11-01

Full Text Available Brett Ley, Harold R Collard Department of Medicine, Division of Pulmonary and Critical Care Medicine, University of California San Francisco, San Francisco, California, USA Abstract: Idiopathic pulmonary fibrosis is a chronic fibrotic lung disease of unknown cause that occurs in adults and has a poor prognosis. Its epidemiology has been difficult to study because of its rarity and evolution in diagnostic and coding practices. Though uncommon, it is likely underappreciated both in terms of its occurrence (ie, incidence, prevalence and public health impact (ie, health care costs and resource utilization. Incidence and mortality appear to be on the rise, and prevalence is expected to increase with the aging population. Potential risk factors include occupational and environmental exposures, tobacco smoking, gastroesophageal reflux, and genetic factors. An accurate understanding of its epidemiology is important, especially as novel therapies are emerging. Keywords: idiopathic pulmonary fibrosis, epidemiology, incidence, prevalence, mortality, risk factors

Varicella in Europe-A review of the epidemiology and experience with vaccination

DEFF Research Database (Denmark)

Helmuth, Ida Glode; Poulsen, Anja; Suppli, Camilla Hiul

2015-01-01

adults. Hospitalisation due to varicella is not common, but complications and hospitalisation mainly affect previously healthy children, which underlines the importance of not dismissing varicella as a disease of little importance. The experience with universal vaccination in Europe shows......There is no consensus as regards the European varicella immunisation policy; some countries have introduced varicella vaccination in their routine childhood immunisation programs whereas others have decided against or are debating. With the aim of providing an overview of the epidemiology...... that vaccination leads to a rapid reduction of disease incidence. Vaccine effectiveness is high and a protective herd effect is obtained. Experience with vaccination in Europe has not been long enough, though, to draw conclusions on benefits and drawbacks with vaccination as well as the capacity for national...

[Urbanization of Chagas disease in Peru: experiences in prevention and control].

Science.gov (United States)

Náquira, César

2014-04-01

In Peru, Chagas disease has an epidemiological significance in three macro-regions, one of them is the southern macro-region formed by the departments of Arequipa, Moquegua and Tacna. In 1965 a successful control was performed by house spraying insecticides, however, the persistence of the vector made it necessary for a second control plan that was implemented in 2000 and followed the guidelines of CONAL Plan, based on the elimination of Triatoma infestans and screening in blood banks.This plan was successful in Tacna and Moquegua, therefore these departments were considered free of vectorial transmission by the Pan American Health Organization. A ssimilar situation has not been achieved in the department of Arequipa because of the presence, among other factors, of rural migration to the city, in this way the urbanization of Chagas disease is a new epidemiological scenario of which we need to know more.

Radon epidemiology: A guide to the literature

International Nuclear Information System (INIS)

Marks, S.

1988-12-01

This document was written as a comprehensive overview of the voluminous literature on both uranium miner and residential radon epidemiology studies. This document provides the reader with a fairly complete list of radon epidemiology publications and key features of each, so that readers may further pursue only those publications of interest in the vast body of radon literature. A companion document, exploring all on-going residential radon epidemiology studies will be published by the Office of Health and Environmental Research (OHER), the Department of Energy (DOE) in the spring of 1989

Epidemiology of eating disorders in Africa.

Science.gov (United States)

van Hoeken, Daphne; Burns, Jonathan K; Hoek, Hans W

2016-11-01

This is the first review of studies on the epidemiology of eating disorders on the African continent. The majority of articles found through our search did not assess formal diagnoses, but only screened for eating attitudes and behaviors. Only four studies - including only one recent study - provided specific epidemiological data on anorexia nervosa, bulimia nervosa, and/or eating disorder not otherwise specified (EDNOS). No cases of anorexia nervosa according to Diagnostic and Statistical Manual of Mental Disorders (DSM)-IV criteria were found among a total of 1476 (young) females. The combined point-prevalence rate of bulimia nervosa is 0.87% (95% CI 0.22-1.51) and of EDNOS is 4.45% (95% CI 2.74-6.16) in young women in Africa. The epidemiological study of eating disorders in Africa is still in its infancy. Over time in total four studies providing epidemiological data on specific, formally assessed eating disorders were found. No cases of anorexia nervosa were reported in African epidemiological studies, which concurs with the very low prevalence rates of anorexia nervosa in Latin Americans and in African Americans in the USA. With the DSM-5 criteria for anorexia nervosa, some women in the African studies would have fulfilled the criteria for anorexia nervosa. The prevalence rate of bulimia nervosa in women in Africa is within the range reported for western populations, as well as African Americans and Latin Americans.

Epidemiology of extremity fractures in the Netherlands

NARCIS (Netherlands)

Beerekamp, M. S. H.; de Muinck Keizer, R. J. O.; Schep, N. W. L.; Ubbink, D. T.; Panneman, M. J. M.; Goslings, J. C.

2017-01-01

Insight in epidemiologic data of extremity fractures is relevant to identify people at risk. By analyzing age- and gender specific fracture incidence and treatment patterns we may adjust future policy, take preventive measures and optimize health care management. Current epidemiologic data on

Epidemiological reference ranges for low-density lipoprotein ...

African Journals Online (AJOL)

Although there is widespread acceptance that total cholesterol (TC) value reference ranges should be based on epidemiological rather than statistical considerations, the epidemiological action limits for Iow-density lipoprotein cholesterol (LDL-C) are still incomplete and only statistical reference ranges for apolipoprotein B ...

Calculating the survival rate and estimated population density of gravid Aedes aegypti (Diptera, Culicidae in Rio de Janeiro, Brazil Determinação da taxa de sobrevivência e estimativa da densidade populacional de fêmeas grávidas de Aedes aegypti (Diptera, Culicidae no Rio de Janeiro, Brasil

Directory of Open Access Journals (Sweden)

Rafael Maciel-de-Freitas

2008-12-01

Full Text Available Population size and daily survival rates of disease vectors are important determinants of vectorial capacity. A mark-release-recapture experiment was conducted in a dengue endemic urban neighborhood of Rio de Janeiro, Brazil, to estimate population size, survival rate and vectorial capacity of Aedes aegypti females using back-pack aspirators and gravid sticky traps (MosquiTRAP. Estimations of the gravid female population size were different when using data gathered from just the MosquiTRAP (3,505 individuals or aspirator (1,470. However Ae. aegypti survival rates and longevity were similar irrespective of the method of capture. Up to 26.3% of released females would be able to survive for more than 10 days, the length of time of the extrinsic incubation period. Vectorial capacity value ranged between 0.01567 and 0.4215 and the basic reproductive number (R0 was estimated to be between 0.0695 and 1.88.O tamanho populacional e a taxa de sobrevivência de vetores de doenças são importantes componentes da capacidade vetorial. Um experimento de marcação-soltura-recaptura foi conduzido numa área urbana endêmica de dengue no Rio de Janeiro, Brasil, para estimar o tamanho populacional, taxa de sobrevivência diária e capacidade vetorial de fêmeas de Aedes aegypti; para tal, usaram-se aspirador costal e armadilha para fêmeas grávidas de Ae. aegypti (MosquiTRAP. Estimativas do tamanho populacional de fêmeas grávidas foram diferentes quando foram analisados dados coletados apenas na MosquiTRAP (3.505 indivíduos e aspiradores (1.470. Por outro lado, taxas de sobrevivência e longevidade de Ae. aegypti foram semelhantes independentemente do método de captura empregado. Até 26,3% das fêmeas seriam capazes de sobreviver mais do que dez dias, tempo equivalente à duração do período de incubação extrínseco. O cálculo da capacidade vetorial revelou valores entre 0,01567 e 0,4215, e o número básico de reprodução foi estimado entre 0,0695 e

Spatial evolutionary epidemiology of spreading epidemics.

Science.gov (United States)

Lion, S; Gandon, S

2016-10-26

Most spatial models of host-parasite interactions either neglect the possibility of pathogen evolution or consider that this process is slow enough for epidemiological dynamics to reach an equilibrium on a fast timescale. Here, we propose a novel approach to jointly model the epidemiological and evolutionary dynamics of spatially structured host and pathogen populations. Starting from a multi-strain epidemiological model, we use a combination of spatial moment equations and quantitative genetics to analyse the dynamics of mean transmission and virulence in the population. A key insight of our approach is that, even in the absence of long-term evolutionary consequences, spatial structure can affect the short-term evolution of pathogens because of the build-up of spatial differentiation in mean virulence. We show that spatial differentiation is driven by a balance between epidemiological and genetic effects, and this quantity is related to the effect of kin competition discussed in previous studies of parasite evolution in spatially structured host populations. Our analysis can be used to understand and predict the transient evolutionary dynamics of pathogens and the emergence of spatial patterns of phenotypic variation. © 2016 The Author(s).

Molecular epidemiology of human rhinoviruses

OpenAIRE

Savolainen-Kopra, Carita

2006-01-01

The first part of this work investigates the molecular epidemiology of a human enterovirus (HEV), echovirus 30 (E-30). This project is part of a series of studies performed in our research team analyzing the molecular epidemiology of HEV-B viruses. A total of 129 virus strains had been isolated in different parts of Europe. The sequence analysis was performed in three different genomic regions: 420 nucleotides (nt) in the VP4/VP2 capsid protein coding region, the entire VP1 capsid protein cod...

Temas de Física para Ingeniería: Campos escalares y vectoriales

OpenAIRE

Beléndez, Augusto; Bernabeu, Guillermo; Pastor Antón, Carlos

1988-01-01

Magnitudes, vectores y campos: "Campos escalares y vectoriales". Campo escalar y campo vectorial. Cálculo vectorial infinitesimal: operadores. Representación vectorial de una superficie. Integración de campos vectoriales. Relaciones entre los campos escalares y vectoriales. Clasificación de los campos vectoriales.

Cultural epidemiology: An introduction and overview

OpenAIRE

Weiss, Mitchell Gralnick

2001-01-01

Although the value of interdisciplinary collaboration between epidemiology and anthropology is both widely acknowledged and hotly contested, effective international health policy and multicultural health programmes require it. The EMIC framework for cultural studies of illness was developed in response to such needs, and a cultural epidemiology emerged from that framework as an interdisciplinary field of research on locally valid representations of illness and their distributions in cultural ...

A two-step recognition of signal sequences determines the translocation efficiency of proteins.

OpenAIRE

Belin, D; Bost, S; Vassalli, J D; Strub, K

1996-01-01

The cytosolic and secreted, N-glycosylated, forms of plasminogen activator inhibitor-2 (PAI-2) are generated by facultative translocation. To study the molecular events that result in the bi-topological distribution of proteins, we determined in vitro the capacities of several signal sequences to bind the signal recognition particle (SRP) during targeting, and to promote vectorial transport of murine PAI-2 (mPAI-2). Interestingly, the six signal sequences we compared (mPAI-2 and three mutated...

Comparison of transmission parameters between Anopheles argyritarsis and Anopheles pseudopunctipennis in two ecologically different localities of Bolivia.

Science.gov (United States)

Lardeux, Frédéric; Aliaga, Claudia; Tejerina, Rosenka; Torrez, Libia

2013-08-13

Anopheles (Anopheles) pseudopunctipennis is a recognized malaria vector in the slopes of the Andes of Bolivia. There, other species might be involved in malaria transmission and one candidate could be Anopheles argyritarsis. Although it is generally admitted that this species is not a malaria vector in the neotropical region, its potential role in transmission is still controversial and this situation has to be cleared, at least for Bolivia. Comparing the vectorial efficiency of An. pseudopunctipennis with that of An. argyritarsis could solve the question. The two species were sampled throughout Bolivia to estimate their degree of co-existence in their distribution range. Vectorial efficiencies of the two species were compared in two ecologically different localities where the species were sympatric by analysing their vectorial capacities and components (i e, human biting rates, human biting index, survival, durations of the gonotrophic cycle and extrinsic cycle), and the entomological inoculation rates (EIR). Mosquitoes were sampled monthly during more than one year in the two localities. A monthly sample consisted in hourly captures in four houses (inside and outside) in each locality, during four consecutive nights. Climatic variables (temperature, humidity, potential evapo-transpiration and precipitations) were recorded to better understand variability in the entomological parameters. Relationships were analysed using multivariate methods. Anopheles pseudopunctipennis and An. argyritarsis are "altitude" species, sharing the same geographical distribution range in the Andes of Bolivia. No Plasmodium parasite was identified in An. argyritarsis and estimates of the vectorial capacity indicated that it is not a malaria vector in the two studied localities, unlike An. pseudopunctipennis which showed positive EIRs. This latter species, although not a very good malaria vector, exhibited better life traits values and better behavioural characteristics in favour of

Epidemiology, diagnosis and management of food allergy

NARCIS (Netherlands)

Le, T.T.M.

2013-01-01

This thesis describes the epidemiology, diagnosis and management of food allergy. Epidemiology This thesis shows that the prevalence of self-reported adverse food reactions in children and adults was high: 17-25% for all foods and 10-11% for 24 preselected, so-called priority foods. The prevalence

Epidemiology in the Era of Big Data

Science.gov (United States)

Mooney, Stephen J; Westreich, Daniel J; El-Sayed, Abdulrahman M

2015-01-01

Big Data has increasingly been promoted as a revolutionary development in the future of science, including epidemiology. However, the definition and implications of Big Data for epidemiology remain unclear. We here provide a working definition of Big Data predicated on the so-called ‘3 Vs’: variety, volume, and velocity. From this definition, we argue that Big Data has evolutionary and revolutionary implications for identifying and intervening on the determinants of population health. We suggest that as more sources of diverse data become publicly available, the ability to combine and refine these data to yield valid answers to epidemiologic questions will be invaluable. We conclude that, while epidemiology as practiced today will continue to be practiced in the Big Data future, a component of our field’s future value lies in integrating subject matter knowledge with increased technical savvy. Our training programs and our visions for future public health interventions should reflect this future. PMID:25756221

Lessons from sea louse and salmon epidemiology.

Science.gov (United States)

Groner, Maya L; Rogers, Luke A; Bateman, Andrew W; Connors, Brendan M; Frazer, L Neil; Godwin, Sean C; Krkošek, Martin; Lewis, Mark A; Peacock, Stephanie J; Rees, Erin E; Revie, Crawford W; Schlägel, Ulrike E

2016-03-05

Effective disease management can benefit from mathematical models that identify drivers of epidemiological change and guide decision-making. This is well illustrated in the host-parasite system of sea lice and salmon, which has been modelled extensively due to the economic costs associated with sea louse infections on salmon farms and the conservation concerns associated with sea louse infections on wild salmon. Consequently, a rich modelling literature devoted to sea louse and salmon epidemiology has been developed. We provide a synthesis of the mathematical and statistical models that have been used to study the epidemiology of sea lice and salmon. These studies span both conceptual and tactical models to quantify the effects of infections on host populations and communities, describe and predict patterns of transmission and dispersal, and guide evidence-based management of wild and farmed salmon. As aquaculture production continues to increase, advances made in modelling sea louse and salmon epidemiology should inform the sustainable management of marine resources. © 2016 The Author(s).

Station Capacity

DEFF Research Database (Denmark)

Landex, Alex

2011-01-01

the probability of conflicts and the minimum headway times into account. The last method analyzes how optimal platform tracks are used by examining the arrival and departure pattern of the trains. The developed methods can either be used separately to analyze specific characteristics of the capacity of a station......Stations are often limiting the capacity of railway networks. This is due to extra need of tracks when trains stand still, trains turning around, and conflicting train routes. Although stations are often the capacity bottlenecks, most capacity analysis methods focus on open line capacity. Therefore...... for platform tracks and the probability that arriving trains will not get a platform track immediately at arrival. The third method is a scalable method that analyzes the conflicts in the switch zone(s). In its simplest stage, the method just analyzes the track layout while the more advanced stages also take...

Public Health Education: Teaching Epidemiology in High School Classrooms.

Science.gov (United States)

D'Agostino, Emily

2018-03-01

Epidemiology instruction has expanded at the undergraduate level in part because it increases student critical thinking and scientific literacy, promotes students' perception of public health as both practical and relevant, and empowers students as independent, lifelong learners. Why then are more high schools not adopting epidemiology as a course requirement for students? Although prior iterations of high school epidemiology courses are noteworthy for incorporating active and participatory learning, embedding them into existing and continually shifting curricula is challenging and time-consuming, especially for teachers not trained in the field. It also may be argued that currently available epidemiology teaching resources emphasize content rather than thinking skills and therefore do not optimally promote students' personal engagement with, and in-depth understanding of, the mission and goals of public health. I propose a new framework for high school epidemiology that draws from progressive education ideology, including three critical elements: empowerment, authenticity, and transfer. I provide multiple examples to show how this framework has been used across a wide array of settings to hone epidemiology thinking skills in high school students.

Epidemiology of Gout

Science.gov (United States)

Choi, Hyon

2014-01-01

Synopsis Gout is the most prevalent inflammatory arthritis in men. The findings of several epidemiological studies from a diverse range of countries suggest that the prevalence of gout has risen over the last few decades. Whilst incidence data are scarce, data from the US suggests that the incidence of gout is also rising. Evidence from prospective epidemiological studies has confirmed dietary factors (animal purines, alcohol and fructose), obesity, the metabolic syndrome, hypertension, diuretic use, and chronic kidney disease as clinically relevant risk factors for hyperuricemia and gout. Low-fat dairy products, coffee, and vitamin C appear to have a protective effect. Further prospective studies are required to examine other proposed risk factors for hyperuricaemia and gout such as the use of β-blockers and angiotension-II receptor antagonists (other than losartan), obstructive sleep apnoea, and osteoarthritis, and putative protective factors such as calcium-channel blockers and losartan. PMID:24703341

Inter-relation of sylvatic and domestic transmission of Trypanosoma cruzi in areas with and without domestic vectorial transmission in Minas Gerais, Brazil

Directory of Open Access Journals (Sweden)

L. Diotaiuti

1995-08-01

Full Text Available During the period 1980-1986, we captured triatomine bugs and mammalian reservoir hosts from sylvatic and domestic situations in different municipalities of the State of Minas Gerais. Trypanosoma cruzi was isolated from captured bugs, mammals and patients. After cultivation in LIT medium, the electrophoretic enzyme profiles were determined. We obtained atotal of 32 parasite isolates from regions with active domestic transmission, and 24 isolates form areas under control. For the first areas the results suggest introduction of T. cruzi from sylvatic habitats, through incursion of infected opossums and/or sylvatic T. sordida, which appears to have given rise to at least one acute human infection. Of particular interest is the finding of sylvatic opossums and a T. sordida nymph infected with ZB, that could indicate return of parasites from chronic human infections to sylvatic transmission cycles. For the areas under control we also interpret the results as interaction between sylvatic and domestic cycles of transmission, here through the invasion of houses by bugs carrying the Z1 zymodeme from the sylvatic environment. The Multivariate Correspondence Analysis gives a spatial description between the different parasite isolates and confirms the existence of a bridge in the opposite direction in the region with active vectorial transmission including the exporting of Z2 through the peridomestic environment into the sylvatic cycle. For the others areas this bridge corresponds especially to Panstrongylus megistus, importing Z1 into the domestic environment.

The European concerted action on air pollution epidemiology

Energy Technology Data Exchange (ETDEWEB)

Ackermann-Liebrich, U. [Basel Univ. (Switzerland). Inst. for Social and Preventive Medicine

1995-12-31

The European Concerted Action on Air Pollution Epidemiology was started in 1990 with the aim of bringing together European researchers in the field and improving research through collaboration and by preparing documents which would help to this end and by organizing workshops. A further aim was to stimulate cooperative research. Air pollution epidemiology investigates human effects of community air pollution by epidemiological methods. Epidemiology in general investigates the distribution and determinants of health-related states and events in populations. Diseases in which air pollution may play a significant role are mainly diseases of the respiratory system, for example chronic non-specific lung disease and lung cancer. Most diseases caused by air pollution can also be caused by other factors. Air pollution epidemiology is therefore specific in the expo variable (community air pollution) rather than in the type of health effects being studied. Air pollution epidemiology is beset with some specially challenging difficulties: ubiquitous exposure and as a consequence limited heterogeneity in exposure, low relative risks, few or specific health end points, and strong confounding. Further on the exposure-effect relationship is complicated by assumptions inherent to different study designs which relate to the exposure duration necessary to produce a certain health effect. In reports and workshops the concerted action tries to propose strategies to deal with these problems. (author)

The European concerted action on air pollution epidemiology

Energy Technology Data Exchange (ETDEWEB)

Ackermann-Liebrich, U [Basel Univ. (Switzerland). Inst. for Social and Preventive Medicine

1996-12-31

The European Concerted Action on Air Pollution Epidemiology was started in 1990 with the aim of bringing together European researchers in the field and improving research through collaboration and by preparing documents which would help to this end and by organizing workshops. A further aim was to stimulate cooperative research. Air pollution epidemiology investigates human effects of community air pollution by epidemiological methods. Epidemiology in general investigates the distribution and determinants of health-related states and events in populations. Diseases in which air pollution may play a significant role are mainly diseases of the respiratory system, for example chronic non-specific lung disease and lung cancer. Most diseases caused by air pollution can also be caused by other factors. Air pollution epidemiology is therefore specific in the expo variable (community air pollution) rather than in the type of health effects being studied. Air pollution epidemiology is beset with some specially challenging difficulties: ubiquitous exposure and as a consequence limited heterogeneity in exposure, low relative risks, few or specific health end points, and strong confounding. Further on the exposure-effect relationship is complicated by assumptions inherent to different study designs which relate to the exposure duration necessary to produce a certain health effect. In reports and workshops the concerted action tries to propose strategies to deal with these problems. (author)

The epidemiology of pneumococcal carriage and infections in Malaysia.

Science.gov (United States)

Le, Cheng-Foh; Jefferies, Johanna M; Yusof, Mohd Yasim Mohd; Sekaran, Shamala Devi; Clarke, Stuart C

2012-06-01

In Malaysia, various aspects of the epidemiology of pneumococcal carriage and disease remain largely unclear due to the lack of supporting data. Although a number of relevant studies have been documented, their individual discrete findings are not sufficient to inform experts on pneumococcal epidemiology at a national level. Therefore, in this review we aim to bring together and systematically evaluate the key information regarding pneumococcal disease epidemiology in Malaysia and provide a comprehensive overview of the data. Major aspects discussed include pneumococcal carriage, disease incidence and prevalence, age factors, invasiveness of pneumococci, serotypes, molecular epidemiology and antibiotic susceptibility. Penicillin resistance is increasingly prevalent and studies suggest that the majority of pneumococcal serotypes causing pneumococcal disease in Malaysia are covered by currently available conjugate vaccines. Continued surveillance is needed to provide a better understanding of pneumococcal epidemiology in Malaysia.

[Precision medicine: new opportunities and challenges for molecular epidemiology].

Science.gov (United States)

Song, Jing; Hu, Yonghua

2016-04-01

Since the completion of the Human Genome Project in 2003 and the announcement of the Precision Medicine Initiative by U.S. President Barack Obama in January 2015, human beings have initially completed the " three steps" of " genomics to biology, genomics to health as well as genomics to society". As a new inter-discipline, the emergence and development of precision medicine have relied on the support and promotion from biological science, basic medicine, clinical medicine, epidemiology, statistics, sociology and information science, etc. Meanwhile, molecular epidemiology is considered to be the core power to promote precision medical as a cross discipline of epidemiology and molecular biology. This article is based on the characteristics and research progress of medicine and molecular epidemiology respectively, focusing on the contribution and significance of molecular epidemiology to precision medicine, and exploring the possible opportunities and challenges in the future.

Ophthalmic epidemiology in Europe : the "European Eye Epidemiology" (E3) consortium

NARCIS (Netherlands)

Delcourt, Cecile; Korobelnik, Jean-Francois; Buitendijk, Gabrielle H. S.; Foster, Paul J.; Hammond, Christopher J.; Piermarocchi, Stefano; Peto, Tunde; Jansonius, Nomdo; Mirshahi, Alireza; Hogg, Ruth E.; Bretillon, Lionel; Topouzis, Fotis; Deak, Gabor; Grauslund, Jakob; Broe, Rebecca; Souied, Eric H.; Creuzot-Garcher, Catherine; Sahel, Jose; Daien, Vincent; Lehtimaki, Terho; Hense, Hans-Werner; Prokofyeva, Elena; Oexle, Konrad; Rahi, Jugnoo S.; Cumberland, Phillippa M.; Schmitz-Valckenberg, Steffen; Fauser, Sascha; Bertelsen, Geir; Hoyng, Carel; Bergen, Arthur; Silva, Rufino; Wolf, Sebastian; Lotery, Andrew; Chakravarthy, Usha; Fletcher, Astrid; Klaver, Caroline C. W.

The European Eye Epidemiology (E3) consortium is a recently formed consortium of 29 groups from 12 European countries. It already comprises 21 population-based studies and 20 other studies (case-control, cases only, randomized trials), providing ophthalmological data on approximately 170,000

The Current Status of the Disease Caused by Enterovirus 71 Infections: Epidemiology, Pathogenesis, Molecular Epidemiology, and Vaccine Development.

Science.gov (United States)

Chang, Ping-Chin; Chen, Shou-Chien; Chen, Kow-Tong

2016-09-09

Enterovirus 71 (EV71) infections have a major public health impact in the Asia-Pacific region. We reviewed the epidemiology, pathogenesis, and molecular epidemiology of EV71 infection as well as EV71 vaccine development. Previous studies were found using the search terms "enterovirus 71" and "epidemiology" or "pathogenesis" or "molecular epidemiology" or "vaccine" in Medline and PubMed. Articles that were not published in the English language, manuscripts without an abstract, and opinion articles were excluded from the review. The reported epidemiology of cases caused by EV71 infection varied from country to country; seasonal variations in incidence were observed. Most cases of EV71 infection that resulted in hospitalization for complications occurred in children less than five years old. The brainstem was the most likely major target of EV71 infection. The emergence of the EV71 epidemic in the Asia-Pacific region has been associated with the circulation of different genetic lineages (genotypes B3, B4, C1, C2, and C4) that appear to be undergoing rapid evolutionary changes. The relationship between the gene structure of the EV71 virus and the factors that ensure its survival, circulation, and evasion of immunity is still unknown. EV71 infection has emerged as an important global public health problem. Vaccine development, including the development of inactivated whole-virus live attenuated, subviral particles, and DNA vaccines, has been progressing.

Epidemiology and ionizing radiations

International Nuclear Information System (INIS)

Bourguignon, M.; Masse, R.; Slama, R.; Spira, A.; Timarche, M.; Laurier, D.; Billon, S.; Rogel, A.; Telle Lamberton, M.; Catelinois, O.; Thierry, I.; Grosche, B.; Ron, E.; Vathaire, F. de; Cherie Challine, L.; Donadieu, J.; Pirard, Ph.; Bloch, J.; Setbon, M.

2004-01-01

The ionizing radiations have effects on living being. The determinist effects appear since a threshold of absorbed dose of radiation is reached. In return, the stochastic effects of ionizing radiations are these ones whom apparition cannot be described except in terms of probabilities. They are in one hand, cancers and leukemia, on the other hand, lesions of the genome potentially transmissible to the descendants. That is why epidemiology, defined by specialists as the science that studies the frequency and distribution of illness in time and space, the contribution of factors that determine this frequency and this distribution among human populations. This issue gathers and synthesizes the knowledge and examines the difficulties of methodologies. It allows to give its true place to epidemiology. (N.C.)

Building research and evaluation capacity in population health: the NSW Health approach.

Science.gov (United States)

Edwards, Barry; Stickney, Beth; Milat, Andrew; Campbell, Danielle; Thackway, Sarah

2016-02-01

Issue addressed An organisational culture that values and uses research and evaluation (R&E) evidence to inform policy and practice is fundamental to improving health outcomes. The 2016 NSW Government Program Evaluation Guidelines recommend investment in training and development to improve evaluation capacity. The purpose of this paper is to outline the approaches taken by the NSW Ministry of Health to develop R&E capacity and assess these against existing models of practice. Method The Ministry of Health's Centre for Epidemiology and Evidence (CEE) takes an evidence-based approach to building R&E capacity in population health. Strategies are informed by: the NSW Population Health Research Strategy, R&E communities of practice across the Ministry and health Pillar agencies and a review of the published evidence on evaluation capacity building (ECB). An internal survey is conducted biennially to monitor research activity within the Ministry's Population and Public Health Division. One representative from each of the six centres that make up the Division coordinates completion of the survey by relevant staff members for their centre. Results The review identified several ECB success factors including: implementing a tailored multifaceted approach; an organisational commitment to R&E; and offering experiential training and ongoing technical support to the workforce. The survey of research activity found that the Division funded a mix of research assets, research funding schemes, research centres and commissioned R&E projects. CEE provides technical advice and support services for staff involved in R&E and in 2015, 22 program evaluations were supported. R&E capacity building also includes a series of guides to assist policy makers, practitioners and researchers to commission, undertake and use policy-relevant R&E. Staff training includes workshops on critical appraisal, program logic and evaluation methods. From January 2013 to June 2014 divisional staff published 84

Possible Northward Introgression of a Tropical Lineage of Rhipicephalus sanguineus Ticks at a Site of Emerging Rocky Mountain Spotted Fever.

Science.gov (United States)

Villarreal, Zachary; Stephenson, Nicole; Foley, Janet

2018-06-01

Increasing rates of Rocky Mountain spotted fever (RMSF) in the southwestern United States and northern Mexico underscore the importance of studying the ecology of the brown dog tick, Rhipicephalus sanguineus, the vector in that region. This species is reported to comprise distinct tropical and temperate lineages that may differ in vectorial capacity for RMSF and are hypothesized to be limited in their geographical range by climatic conditions. In this study, lineage was determined for ticks from 9 locations in California, Arizona, and Mexico by DNA sequencing of 12S, 16S, and D-loop ribosomal RNA. As expected, sites in northern California and eastern Arizona had temperate-lineage ticks, and phylogenetic analysis revealed considerable genetic variability among these temperate-lineage ticks. However, tropical-lineage ticks extended north from Oaxaca, Mexico were well established along the entire border from San Diego, California to western Arizona, and were found as far north as Lytle Creek near Los Angeles, California (a site where both lineages were detected). Far less genetic variability in the tropical lineage despite the large geographical distances is supportive of a hypothesis of rapid northward expansion. Discovery of the tropical lineage north of the identified climatic limitations suggests that more work is needed to characterize this tick's ecology, vectorial capacity, expansion, possible evolution, and response to climate change.

Epidemiological studies of cognitive impairment and dementia across Eastern and Middle European countries (epidemiology of dementia in Eastern and Middle European Countries).

Science.gov (United States)

Kiejna, A; Frydecka, D; Adamowski, T; Bickel, H; Reynish, E; Prince, M; Caracciolo, B; Fratiglioni, L; Georges, J

2011-02-01

To determine the availability and the consistency of prevalence findings of epidemiological studies on cognitive impairment and dementia conducted in Eastern and Middle Europe. We adopted a stepwise multimethod study approach consisting of iterative literature searches for epidemiological articles published between 1990 and 2006 and subsequent data analyses of published material, reanalyses of existing accessible epidemiological data sets and expert inquiries in Eastern and Middle European countries. Systematic computer-assisted searches used the keywords: "dementia", "Alzheimer", "cognitive impairment", "incidence", "prevalence", "epidemiology" in combination with the name of the relevant countries or "Europe" in English and Polish language. We supplemented the literature search with a review of the references in the articles that were identified during the initial search. We were able to find few regional and country-specific epidemiological studies of various kinds (population-based, cohort, cross-sectional studies) and conducted on different restricted population groups of patients (from neurological units, out-patients units, residential homes). No studies were identified from most of the countries taken under consideration and the ones we found were characterized by an immense diversity with a considerable degree of clinical and methodological variations. The few studies that there are suggest prevalence rates of dementia in Eastern Europe similar to those in Western Europe. There is strong need for epidemiological studies in Eastern and Middle Europe, as well as for greater coordination and standardization of methods to improve the quality and comparability of epidemiological data to determine the prevalences' rates of dementia in all the EU countries. Copyright © 2010 John Wiley & Sons, Ltd.

Review on the epidemiology and dynamics of BSE epidemics.

Science.gov (United States)

Ducrot, Christian; Arnold, Mark; de Koeijer, Aline; Heim, Dagmar; Calavas, Didier

2008-01-01

The paper describes how the comprehensive surveillance of bovine spongiform encephalopathy (BSE) and studies carried out on these data has enhanced our knowledge of the epidemiology of BSE. Around 7, 000 BSE cases were detected through the screening of about 50 million cattle with rapid tests in Europe. It confirmed that the clinical surveillance had a poor capacity to detect cases, and also showed the discrepancy of this passive surveillance efficiency between regions and production types (dairy/beef). Other risk factors for BSE were being in a dairy herd (three times more than beef), having a young age at first calving (for dairy cattle), being autumn-born (dairy and beef), and being in a herd with a very high milk yield. These findings focus the risk on the feeding regimen of calves/heifers. Several epidemiological studies across countries suggest that the feedborne source related to meat and bone meal (MBM) is the only substantiated route of infection - even after the feed ban -, while it is not possible to exclude maternal transmission or milk replacers as a source of some infections. In most European countries, the average age of the cases is increasing over time and the prevalence decreasing, which reflects the effectiveness of control measures. Consistent results on the trend of the epidemic were obtained using back-calculation modelling, the R(0) approach and Age-Period-Cohort models. Furthermore, active surveillance also resulted in the finding of atypical cases. These are distinct from previously found BSE and classified in two different forms based on biochemical characteristics; their prevalence is very low (36 cases up to 1st September 2007), affected animals were old and some of them displayed clinical signs. The origin and possibility of natural transmission is unknown.

Epidemiology & Genomics Research Program

Science.gov (United States)

The Epidemiology and Genomics Research Program, in the National Cancer Institute's Division of Cancer Control and Population Sciences, funds research in human populations to understand the determinants of cancer occurrence and outcomes.

Epidemiology of burns

NARCIS (Netherlands)

Dokter, Jan

2016-01-01

The aim of this thesis is to understand the epidemiology, treatment and outcomes of specialized burn care in The Netherlands. This thesis is mainly based on historical data of the burn centre in Rotterdam from 1986, combined with historical data from the burn centres in Groningen and Beverwijk from

Larval Habitat Substrates Could Affect the Biology and Vectorial Capacity of Culex quinquefasciatus (Diptera: Culicidae).

Science.gov (United States)

Shah, Rizwan Mustafa; Ali, Qasim; Alam, Mehboob; Shad, Sarfraz Ali; Majeed, Shahid; Riaz, Muhammad; Binyameen, Muhammad

2017-05-01

Culex quinquefasciatus Say is an important disease vector throughout much of the world. Experiments were conducted to determine the effects of different larval habitat substrates on the fitness and biting efficiency of Cx. quinquefasciatus adults. Our findings indicate that the development time (egg to adult) of larvae reared in irrigation water was 8.63 d while that of larvae reared in distilled water was 17.10 d (Effect size = 0.95). However, the rate of adult emergence was similar for all the tested treatments. Furthermore, the mean weight of an egg raft varied between larval habitats: distilled water (1.83 mg), rainfall water (1.25 mg), irrigation water (1.52 mg), and sewerage water (2.52 mg) (Effect size = 0.91). But, the fecundity (eggs per female) and hatchability (%) were statistically similar in all the rearing mediums (Effect size = 0.79). Longevity of females in all the tested populations did not differ significantly (Effect size = 0.91). The mean relative growth rates of larvae reared in tap water (0.80) and distilled water (0.86) habitats were lower than growth rates in all other rearing habitats (Effect size = 0.96). The intrinsic rate of natural increase in tap water (0.27) and irrigation water (0.35) was significantly higher than that in distilled water (0.09) and sewerage water (0.16) (Effect size = 0.84). Adults reared in rain water had the highest biting efficiency among all the tested populations. These results provide useful information for the management of Cx. quinquefasciatus. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Capacity Measurement with the UIC 406 Capacity Method

DEFF Research Database (Denmark)

Landex, Alex; Schittenhelm, Bernd; Kaas, Anders H.

2008-01-01

This article describes the fast and effective UIC 406 method for calculating capacity consumption on railway lines. It is possible to expound the UIC 406 method in different ways which can lead to different capacity consumptions. Therefore, this article describes how the methodology is expounded...

Epidemiology of infectious meningitis in the State of Amazonas, Brazil

Directory of Open Access Journals (Sweden)

Maria das Graças Gomes Saraiva

2015-06-01

Full Text Available INTRODUCTION: In the State of Amazonas, particularly in the capital Manaus, meningitis has affected populations of different cultures and social strata over the years. Bacterial meningitis is caused by several different species and represents a major issue of public health importance. The present study reports the meningitis case numbers with different etiologies in Amazonas from January 1976 to December 2012. METHODS: Since the 1970s, the (currently named Tropical Medicine Foundation of Doutor Heitor Vieira Dourado [Fundação de Medicina Tropical Doutor Heitor Vieira Dourado (FMT-HVD] has remained a reference center in Amazonas for the treatment of meningitis through the diagnosis and notification of cases and the confirmation of such cases using specific laboratory tests. RESULTS: The foundation has achieved coverage of over 90% of the state medical records for many years. Between 1990 and 2012, meningitis cases caused by Haemophilus influenzae decreased with the introduction of the H. influenzae vaccine. Meningococcal disease previously had a higher frequency of serogroup B disease, but starting in 2008, the detection of serogroup C increased gradually and has outpaced the detection of serogroup B. Recently, surveillance has improved the etiological definition of viral meningitis at FMT-HVD, with enteroviruses, Epstein-Barr virus (EBV and varicella zoster virus (VZV prevailing in this group of pathogens. With the advent of acquired immunodeficiency syndrome (AIDS, cryptococcal meningitis has become an important disease in Amazonas. Additionally, infectious meningitis is an important burden in the State of Amazonas. CONCLUSIONS: Changes in the epidemiological profile for the different etiology-defined cases are the result of continuous epidemiological surveillance and laboratory capacity improvements and control measures, such as Haemophilus influenzae vaccination.

ADHD in the Arab World: A Review of Epidemiologic Studies

Science.gov (United States)

Farah, Lynn G.; Fayyad, John A.; Eapen, Valsamma; Cassir,Youmna; Salamoun, Mariana M.; Tabet, Caroline C.; Mneimneh, Zeina N.; Karam, Elie G.

2009-01-01

Objective: Epidemiological studies on psychiatric disorders are quite rare in the Arab World. This article reviews epidemiological studies on ADHD in all the Arab countries. Method: All epidemiological studies on ADHD conducted from 1966 through th present were reviewed. Samples were drawn from the general community, primary care clinical…

Responsibility and Capacities

DEFF Research Database (Denmark)

Ryberg, Jesper

2014-01-01

That responsible moral agency presupposes certain mental capacities, constitutes a widely accepted view among theorists. Moreover, it is often assumed that degrees in the development of the relevant capacities co-vary with degrees of responsibility. In this article it is argued that, the move from...... the view that responsibility requires certain mental capacities to the position that degrees of responsibility co-vary with degrees of the development of the mental capacities, is premature....

Worldwide Report, Epidemiology, No. 327

National Research Council Canada - National Science Library

1983-01-01

Partial Contents: Epidemiology, Human Diseases, Health, Malaria, AIDS, Homosexual Male, Medical Administration, Rabies, Tuberculosis, Encephalitis Statistics, Gastroenteritie, Mystery Diseases, Children, Epidemics...

La vulnerabilidad humana a la transmisión vectorial de Trypanosoma cruzi a través de los procesos de salud-enfermedad y la apropiación social del territorio

Directory of Open Access Journals (Sweden)

Alba Rocío Valdez Tah

2015-01-01

Full Text Available Los estudios sobre el riesgo de la transmisión vectorial de Trypanosoma cruzi a población humana han desatendido el rol del comportamiento y de la subjetividad de las relaciones sociales en el marco del paisaje natural y el contexto social. A través de una revisión y síntesis de la bibliografía sobre los factores biológicos, ecoepidemiológicos y socioculturales que intervienen en el fenómeno, en conjunto con un estudio etnográfico, se propone un modelo de análisis del riesgo que distingue los componentes de peligro y de la vulnerabilidad humana. Los conocimientos, prácticas y representaciones sociales respecto del proceso salud-enfermedad-atención y de la apropiación social del territorio se plantean como elementos explicativos de la vulnerabilidad humana. Los componentes de la vulnerabilidad propuestos se exploran en el marco de un análisis etnográfico, que permite identificar opciones y medidas preventivas o de control integral del riesgo más adecuadas.

The application of epidemiology in aquatic animal health -opportunities and challenges

Science.gov (United States)

2011-01-01

Over recent years the growth in aquaculture, accompanied by the emergence of new and transboundary diseases, has stimulated epidemiological studies of aquatic animal diseases. Great potential exists for both observational and theoretical approaches to investigate the processes driving emergence but, to date, compared to terrestrial systems, relatively few studies exist in aquatic animals. Research using risk methods has assessed routes of introduction of aquatic animal pathogens to facilitate safe trade (e.g. import risk analyses) and support biosecurity. Epidemiological studies of risk factors for disease in aquaculture (most notably Atlantic salmon farming) have effectively supported control measures. Methods developed for terrestrial livestock diseases (e.g. risk-based surveillance) could improve the capacity of aquatic animal surveillance systems to detect disease incursions and emergence. The study of disease in wild populations presents many challenges and the judicious use of theoretical models offers some solutions. Models, parameterised from observational studies of host pathogen interactions, have been used to extrapolate estimates of impacts on the individual to the population level. These have proved effective in estimating the likely impact of parasite infections on wild salmonid populations in Switzerland and Canada (where the importance of farmed salmon as a reservoir of infection was investigated). A lack of data is often the key constraint in the application of new approaches to surveillance and modelling. The need for epidemiological approaches to protect aquatic animal health will inevitably increase in the face of the combined challenges of climate change, increasing anthropogenic pressures, limited water sources and the growth in aquaculture. Table of contents 1 Introduction 4 2 The development of aquatic epidemiology 7 3 Transboundary and emerging diseases 9 3.1 Import risk analysis (IRA) 10 3.2 Aquaculture and disease emergence 11 3.3 Climate

The High-Density Lipoprotein Puzzle: Why Classic Epidemiology, Genetic Epidemiology, and Clinical Trials Conflict?

Science.gov (United States)

Rosenson, Robert S

2016-05-01

Classical epidemiology has established the incremental contribution of the high-density lipoprotein (HDL) cholesterol measure in the assessment of atherosclerotic cardiovascular disease risk; yet, genetic epidemiology does not support a causal relationship between HDL cholesterol and the future risk of myocardial infarction. Therapeutic interventions directed toward cholesterol loading of the HDL particle have been based on epidemiological studies that have established HDL cholesterol as a biomarker of atherosclerotic cardiovascular risk. However, therapeutic interventions such as niacin, cholesteryl ester transfer protein inhibitors increase HDL cholesterol in patients treated with statins, but have repeatedly failed to reduce cardiovascular events. Statin therapy interferes with ATP-binding cassette transporter-mediated macrophage cholesterol efflux via miR33 and thus may diminish certain HDL functional properties. Unraveling the HDL puzzle will require continued technical advances in the characterization and quantification of multiple HDL subclasses and their functional properties. Key mechanistic criteria for clinical outcomes trials with HDL-based therapies include formation of HDL subclasses that improve the efficiency of macrophage cholesterol efflux and compositional changes in the proteome and lipidome of the HDL particle that are associated with improved antioxidant and anti-inflammatory properties. These measures require validation in genetic studies and clinical trials of HDL-based therapies on the background of statins. © 2016 American Heart Association, Inc.

Genesis of Preeclampsia: An Epidemiological Approach

Science.gov (United States)

Salvador-Moysén, Jaime; Martínez-López, Yolanda; Ramírez-Aranda, José M.; Aguilar-Durán, Marisela; Terrones-González, Alberto

2012-01-01

There are analyzed some of the main aspects related to the causality of preeclampsia, privileging two types of models: the clinic model and the epidemiologic model, first one represented by the hypothesis of the reduced placental perfusion and the second one considering the epidemiologic findings related to the high levels of psychosocial stress and its association with preeclampsia. It is reasoned out the relevance of raising the causality of the disease from an interdisciplinary perspective, integrating the valuable information generated from both types, clinical and epidemiologic, and finally a tentative explanatory model of preeclampsia is proposed, the subclinical and sociocultural aspects that predispose and trigger the disease are emphasized making aspects to stand out: the importance of reduced placental perfusion as an indicator of individual risk, and the high levels of physiological stress, as a result of the unfavorable conditions of the psychosocial surroundings (indicator of population risk) of the pregnant women. PMID:22462008

Epidemiological characterization of oral cancer. Study Protocol.

Directory of Open Access Journals (Sweden)

Alejandra Fernández

2015-04-01

Full Text Available Oral cancer is a disease of high impact globally. It ranks as the sixth more frequent one among all types of cancer. In spite of being a widely known pathology and easy access to the diagnosis, the lack of epidemiological data reported in the last 10 years in Chile called attention to. At the global level, the World Health Organization (WHO has developed a project called “GLOBOCAN” in order to collect epidemiological data of the global cancer, between its data, highlights the high incidence and high rate of mortality in the male sex, parameter that shows tendency to replicate in both America and Chile. In consequence to these data, a narrative review of the literature concerning the epidemiological profile of the different forms of oral cancer in the past 15 years was done. The diagnosis of oral cancer crosses transversely the Dental Science, forcing us to establish triads of work between oral and maxillofacial surgeons, pathologists and dentists of the various specialties, so as to allow a timely research, appropriate biopsies and histopathological studies finishes with the purpose of, on the one hand, obtain timely and accurate diagnostics, in addition, maintaining the epidemiological indicators.

Ethics Guidelines in Environmental Epidemiology: Their Development and Challenges We Face.

Science.gov (United States)

Kramer, Shira; Soskolne, Colin L

2017-06-01

This review integrates historical developments and key events in bringing ethics into epidemiology in general and into environmental epidemiology in particular. The goal is to provide context for and discern among the various approaches and motivations that drive the need for ethical conduct in support of the public interest. The need for ethics guidelines in epidemiology is different from developments in other biomedical-related fields by virtue of its focus on populations rather than on individuals. The need for ethics guidelines in environmental epidemiology as a subspecialty of epidemiology stems from the larger scale of its mission than that of epidemiology per se. Ethics guidelines in the field of environmental epidemiology have been established. They articulate not only the profession's core values and mission, but more specifically, they address the environmental epidemiologist's obligations to the participants in research, to colleagues, and to employers. They are the product of consensus, scholarship, and diligent stewardship over several decades. The next challenge is ensuring their value and impact. The forces that support professional and institutional success, and the power of special interests, are the major threats to achieving the goals of ethical conduct and research for the public good. In environmental epidemiology, these threats have global implications.

El papel de la epidemiología en la investigación de los trastornos mentales The role of epidemiology in mental disorder research

Directory of Open Access Journals (Sweden)

Guilherme Borges

2004-10-01

Full Text Available Los trastornos mentales, incluyendo los trastornos del uso de sustancias, hacen ya parte del panorama epidemiológico de México y seguirán en el escenario nacional por las próximas décadas, incrementando incluso su presencia como causa de enfermedad, discapacidad y muerte en nuestro país. Por lo tanto, el manejo epidemiológico de estos problemas se hace urgente. Este trabajo busca plantear el campo de estudio de la epidemiología de los trastornos mentales y sus limitaciones, haciendo énfasis en los elementos comunes de ésta con otras áreas más tradicionales de la epidemiología y en las aportaciones particulares de este campo epidemiológico a la psiquiatría en general y a la epidemiología en particular. Planteamos a continuación los diseños y problemas más comunes en este campo de la epidemiología, su utilidad para acciones de prevención, y señalamos los retos que nos esperan en el futuro. Una característica distintiva de esta área es que los trastornos mentales se manifiestan en dos niveles, como conducta (por ejemplo, una conducta compulsiva de lavarse las manos y como elemento de la vida mental del sujeto (por ejemplo, el pensamiento obsesivo sobre las bacterias que se encuentran presentes en todos lados y que son una fuente constante de amenaza para algunos sujetos. Debido a esto, mucho de lo que sabemos sobre estos fenómenos proviene del autorreporte que el sujeto es capaz de hacer sobre sus sentimientos (introspección, ya sea en una conversación con un clínico entrenado o expresándolos al endosar reactivos en un cuestionario estandarizado. Otro aspecto importante a resaltar es la necesidad de hablar en plural al referirnos a los trastornos mentales. Este campo de la epidemiología presenta también un carácter particular, bifacético: por un lado, este es un problema en sí mismo, que produce sufrimiento y motiva la búsqueda de atención especializada, con manifestaciones clínicas particulares. Por otro lado

The Rwanda Field Epidemiology and Laboratory Training Program ...

African Journals Online (AJOL)

The Rwanda Field Epidemiology and Laboratory Training Program (RFELTP) is a 2-year public health leadership development training program that provides applied epidemiology and public health laboratory training while the trainees provide public health service to the Ministry of Health. RFELTP is hosted at the National ...

Integrated flexible capacity and inventory management under flexible capacity uncertainty

OpenAIRE

Paç, Mehmet Fazıl

2006-01-01

Cataloged from PDF version of article. In a manufacturing environment with volatile demand, inventory management can be coupled with dynamic capacity adjustments for handling the fluctuations more effectively. In this study we consider the integrated management of inventory and flexible capacity management under seasonal stochastic demand and uncertain labor supply. The capacity planning problem is investigated from the workforce planning perspective. We consider a manufactu...

Commentary: Epidemiology in the era of big data.

Science.gov (United States)

Mooney, Stephen J; Westreich, Daniel J; El-Sayed, Abdulrahman M

2015-05-01

Big Data has increasingly been promoted as a revolutionary development in the future of science, including epidemiology. However, the definition and implications of Big Data for epidemiology remain unclear. We here provide a working definition of Big Data predicated on the so-called "three V's": variety, volume, and velocity. From this definition, we argue that Big Data has evolutionary and revolutionary implications for identifying and intervening on the determinants of population health. We suggest that as more sources of diverse data become publicly available, the ability to combine and refine these data to yield valid answers to epidemiologic questions will be invaluable. We conclude that while epidemiology as practiced today will continue to be practiced in the Big Data future, a component of our field's future value lies in integrating subject matter knowledge with increased technical savvy. Our training programs and our visions for future public health interventions should reflect this future.

Population-Based Study of the Epidemiology of Herpes Zoster in Korea

OpenAIRE

Kim, You Jeong; Lee, Chang Nam; Lim, Chi-Yeon; Jeon, Woo Seok; Park, Young Min

2014-01-01

General epidemiological data regarding herpes zoster (HZ) are necessary for treatment and prevention of this disease. In addition, epidemiological data can play an important role in evaluating the efficacy and impact of vaccination. Though several epidemiological studies of HZ in Korea have been conducted, they usually depend on hospital-based data and may not be representative of HZ characteristics all over Korea. The purpose of this study was to evaluate the incidence and other epidemiologi...

The emergence of translational epidemiology: from scientific discovery to population health impact.

Science.gov (United States)

Khoury, Muin J; Gwinn, Marta; Ioannidis, John P A

2010-09-01

Recent emphasis on translational research (TR) is highlighting the role of epidemiology in translating scientific discoveries into population health impact. The authors present applications of epidemiology in TR through 4 phases designated T1-T4, illustrated by examples from human genomics. In T1, epidemiology explores the role of a basic scientific discovery (e.g., a disease risk factor or biomarker) in developing a "candidate application" for use in practice (e.g., a test used to guide interventions). In T2, epidemiology can help to evaluate the efficacy of a candidate application by using observational studies and randomized controlled trials. In T3, epidemiology can help to assess facilitators and barriers for uptake and implementation of candidate applications in practice. In T4, epidemiology can help to assess the impact of using candidate applications on population health outcomes. Epidemiology also has a leading role in knowledge synthesis, especially using quantitative methods (e.g., meta-analysis). To explore the emergence of TR in epidemiology, the authors compared articles published in selected issues of the Journal in 1999 and 2009. The proportion of articles identified as translational doubled from 16% (11/69) in 1999 to 33% (22/66) in 2009 (P = 0.02). Epidemiology is increasingly recognized as an important component of TR. By quantifying and integrating knowledge across disciplines, epidemiology provides crucial methods and tools for TR.

Vectorial electron transfer for improved hydrogen evolution by mercaptopropionic-acid-regulated CdSe quantum-dots-TiO2 -Ni(OH)2 assembly.

Science.gov (United States)

Yu, Shan; Li, Zhi-Jun; Fan, Xiang-Bing; Li, Jia-Xin; Zhan, Fei; Li, Xu-Bing; Tao, Ye; Tung, Chen-Ho; Wu, Li-Zhu

2015-02-01

A visible-light-induced hydrogen evolution system based on a CdSe quantum dots (QDs)-TiO2 -Ni(OH)2 ternary assembly has been constructed under an ambient environment, and a bifunctional molecular linker, mercaptopropionic acid, is used to facilitate the interaction between CdSe QDs and TiO2 . This hydrogen evolution system works effectively in a basic aqueous solution (pH 11.0) to achieve a hydrogen evolution rate of 10.1 mmol g(-1)  h(-1) for the assembly and a turnover frequency of 5140 h(-1) with respect to CdSe QDs (10 h); the latter is comparable with the highest value reported for QD systems in an acidic environment. X-ray photoelectron spectroscopy, X-ray absorption spectroscopy, and control experiments demonstrate that Ni(OH)2 is an efficient hydrogen evolution catalyst. In addition, inductively coupled plasma optical emission spectroscopy and the emission decay of the assembly combined with the hydrogen evolution experiments show that TiO2 functions mainly as the electron mediator; the vectorial electron transfer from CdSe QDs to TiO2 and then from TiO2 to Ni(OH)2 enhances the efficiency for hydrogen evolution. The assembly comprises light antenna CdSe QDs, electron mediator TiO2 , and catalytic Ni(OH)2 , which mimics the strategy of photosynthesis exploited in nature and takes us a step further towards artificial photosynthesis. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Issues in epidemiological studies of radiofrequency workers

International Nuclear Information System (INIS)

Hocking, B.

1985-01-01

The paper reviews some of the issues in a proposed epidemiological study of radiofrequency workers. First a few other epidemiological studies are discussed to illustrate some of the common problems such as inadequate definition of effects and/or exposure. Then technical problems in determining dosage and responses as well as study design are reviewed, and finally the administrative aspects of ethics, industrial relations and costs are considered

Epidemiological studies on syncope

DEFF Research Database (Denmark)

Ruwald, Martin Huth

2013-01-01

of the patients play an essential role. In epidemiology these factors have major impact on the outcome of the patients. Until recently, even the definition of syncope differed from one study to another which has made literature reviews difficult. Traditionally the data on epidemiology of syncope has been taken...... from smaller studies from different clinical settings with wide differences in patient morbidity. Through the extensive Danish registries we examined the characteristics and prognosis of the patients hospitalized due to syncope in a nationwide study. The aims of the present thesis were to investigate......, prevalence and cardiovascular factors associated with the risk of syncope, 4) the prognosis in healthy individuals discharged after syncope, and 5) the prognosis of patients after syncope and evaluation of the CHADS2 score as a tool for short- and long-term risk prediction. The first studies of the present...

Book citations: influence of epidemiologic thought in the academic community

Directory of Open Access Journals (Sweden)

Porta Miquel

2006-01-01

Full Text Available Whilst their 'death' has often been certified, books remain highly important to most professions and academic disciplines. Analyses of citations received by epidemiologic texts may complement other views on epidemiology. The objective was to assess the number of citations received by some books of epidemiology and public health, as a first step towards studying the influence of epidemiological thought and thinking in academia. For this purpose, Institute for Scientific Information/ Thomson Scientific - Web of Science/ Web of Knowledgedatabase was consulted, in May 2006. The book by Rothman & Greenland appeared to have received the highest number of citations overall (over 8,000 and per year. The books by Kleinbaum et al, and by Breslow & Day received around 5,000 citations. In terms of citations per year the book by Sackett et al ranks 3rd, and the one by Rose, 4th of those included in this preliminary study. Other books which were influential in the classrooms collected comparatively less citations. Results offer a rich picture of the academic influences and trends of epidemiologic methods and reasoning on public health, clinical medicine and the other health, life and social sciences. They may contribute to assess epidemiologists' efforts to demarcate epidemiology and to assert epistemic authority, and to analyze some historical influences of economic, social and political forces on epidemiological research.

A Systematic Bayesian Integration of Epidemiological and Genetic Data

Science.gov (United States)

Lau, Max S. Y.; Marion, Glenn; Streftaris, George; Gibson, Gavin

2015-01-01

Genetic sequence data on pathogens have great potential to inform inference of their transmission dynamics ultimately leading to better disease control. Where genetic change and disease transmission occur on comparable timescales additional information can be inferred via the joint analysis of such genetic sequence data and epidemiological observations based on clinical symptoms and diagnostic tests. Although recently introduced approaches represent substantial progress, for computational reasons they approximate genuine joint inference of disease dynamics and genetic change in the pathogen population, capturing partially the joint epidemiological-evolutionary dynamics. Improved methods are needed to fully integrate such genetic data with epidemiological observations, for achieving a more robust inference of the transmission tree and other key epidemiological parameters such as latent periods. Here, building on current literature, a novel Bayesian framework is proposed that infers simultaneously and explicitly the transmission tree and unobserved transmitted pathogen sequences. Our framework facilitates the use of realistic likelihood functions and enables systematic and genuine joint inference of the epidemiological-evolutionary process from partially observed outbreaks. Using simulated data it is shown that this approach is able to infer accurately joint epidemiological-evolutionary dynamics, even when pathogen sequences and epidemiological data are incomplete, and when sequences are available for only a fraction of exposures. These results also characterise and quantify the value of incomplete and partial sequence data, which has important implications for sampling design, and demonstrate the abilities of the introduced method to identify multiple clusters within an outbreak. The framework is used to analyse an outbreak of foot-and-mouth disease in the UK, enhancing current understanding of its transmission dynamics and evolutionary process. PMID:26599399

Toxicology and Epidemiology: Improving the Science with a Framework for Combining Toxicological and Epidemiological Evidence to Establish Causal Inference

Science.gov (United States)

Adami, Hans-Olov; Berry, Sir Colin L.; Breckenridge, Charles B.; Smith, Lewis L.; Swenberg, James A.; Trichopoulos, Dimitrios; Weiss, Noel S.; Pastoor, Timothy P.

2011-01-01

Historically, toxicology has played a significant role in verifying conclusions drawn on the basis of epidemiological findings. Agents that were suggested to have a role in human diseases have been tested in animals to firmly establish a causative link. Bacterial pathogens are perhaps the oldest examples, and tobacco smoke and lung cancer and asbestos and mesothelioma provide two more recent examples. With the advent of toxicity testing guidelines and protocols, toxicology took on a role that was intended to anticipate or predict potential adverse effects in humans, and epidemiology, in many cases, served a role in verifying or negating these toxicological predictions. The coupled role of epidemiology and toxicology in discerning human health effects by environmental agents is obvious, but there is currently no systematic and transparent way to bring the data and analysis of the two disciplines together in a way that provides a unified view on an adverse causal relationship between an agent and a disease. In working to advance the interaction between the fields of toxicology and epidemiology, we propose here a five-step “Epid-Tox” process that would focus on: (1) collection of all relevant studies, (2) assessment of their quality, (3) evaluation of the weight of evidence, (4) assignment of a scalable conclusion, and (5) placement on a causal relationship grid. The causal relationship grid provides a clear view of how epidemiological and toxicological data intersect, permits straightforward conclusions with regard to a causal relationship between agent and effect, and can show how additional data can influence conclusions of causality. PMID:21561883

An Epidemiological Study of Accidents in a Construction Industry: A Case-Control Study

Directory of Open Access Journals (Sweden)

Malakouti J.

2013-01-01

Full Text Available Background and Objectives: Despite science and technology development and their application in various industries, accidents continue to occur in many workplaces. This study was designed and carried out with the aim of epidemiological survey of accident among workers of a tunneling industry.Methods: This study was conducted on 144 out of a total of 440 employees of a tunneling project who were at risk of occupational accidents. 48 workers with a history of occupational accident over the past two years were selected as case group and 96 workers of the same project were selected as control group. The data were collected through a designed checklist and analyzed using logistic regression, chi-square and independent t tests.Results: A significant association was observed between accident rate and different age groups (p<0.05. There was a significant relationship (p=0.016 in the case of sport activities between case and control groups, and significant relationships were observed between two groups regarding education (p=0.057 and smoking (p=0.06, but there was no significant relationships between accident occurrence with marital status, residence in workplace, job related education, job experience, chronic diseases and obesity.Conclusion: The results of this study clarify the necessity of the use of epidemiological data in preventive and control measures in workplaces. Therefore, Developing programs for determination of physical and mental capacity of workers are essential to employ them in jobs commensurate with their abilities, especially in older workers.

Resurgence of pertussis at the age of vaccination: clinical, epidemiological, and molecular aspects

Directory of Open Access Journals (Sweden)

Rosângela S.L.A. Torres

2015-08-01

Full Text Available OBJECTIVE: Report the incidence, epidemiology, clinical features, death, and vaccination status of patients with whooping cough and perform genotypic characterization of isolates of B. pertussis identified in the state of Paraná, during January 2007 to December 2013.METHODS: Cross-sectional study including 1,209 patients with pertussis. Data were obtained through the Notifiable Diseases Information System (Sistema de Informação de Agravos de Notificação - SINAN and molecular epidemiology was performed by repetitive sequence-based polymerase chain reaction (rep-PCR; DiversiLab(r, bioMerieux, France.RESULTS: The incidence of pertussis in the state of Paraná increased sharply from 0.15-0.76 per 100,000 habitants between 2007-2010 to 1.7-4.28 per 100,000 between 2011-2013. Patients with less than 1 year of age were more stricken (67.5%. Fifty-nine children (5% developed pertussis even after receiving three doses and two diphtheria-tetanus-pertussis (DTP boosters vaccine. The most common complications were pneumonia (14.5%, otitis (0.9%, and encephalopathy (0.7%. Isolates of B. pertussis were grouped into two groups (G1 and G2 and eight distinct patterns (G1: P1-P5 and G2: P6-P8.CONCLUSION: The resurgence of pertussis should stimulate new research to develop vaccines with greater capacity of protection against current clones and also encourage implementation of new strategies for vaccination in order to reduce the risk of disease in infants.

Epidemiology of autoimmune diseases in Denmark

DEFF Research Database (Denmark)

Eaton, William W.; Rose, N.R.; Kalaydijan, A.

2007-01-01

An epidemiologic study of the autoimmune diseases taken together has not been done heretofore. The National Patient Register of Denmark is used to estimate the population prevalence of 31 possible or probable autoimmune diseases. Record linkage is used to estimate 465 pairwise co-morbidities in i......An epidemiologic study of the autoimmune diseases taken together has not been done heretofore. The National Patient Register of Denmark is used to estimate the population prevalence of 31 possible or probable autoimmune diseases. Record linkage is used to estimate 465 pairwise co...

Representation of Solar Capacity Value in the ReEDS Capacity Expansion Model

Energy Technology Data Exchange (ETDEWEB)

Sigrin, B. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Sullivan, P. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Ibanez, E. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Margolis, R. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2014-03-01

An important issue for electricity system operators is the estimation of renewables' capacity contributions to reliably meeting system demand, or their capacity value. While the capacity value of thermal generation can be estimated easily, assessment of wind and solar requires a more nuanced approach due to the resource variability. Reliability-based methods, particularly assessment of the Effective Load-Carrying Capacity, are considered to be the most robust and widely-accepted techniques for addressing this resource variability. This report compares estimates of solar PV capacity value by the Regional Energy Deployment System (ReEDS) capacity expansion model against two sources. The first comparison is against values published by utilities or other entities for known electrical systems at existing solar penetration levels. The second comparison is against a time-series ELCC simulation tool for high renewable penetration scenarios in the Western Interconnection. Results from the ReEDS model are found to compare well with both comparisons, despite being resolved at a super-hourly temporal resolution. Two results are relevant for other capacity-based models that use a super-hourly resolution to model solar capacity value. First, solar capacity value should not be parameterized as a static value, but must decay with increasing penetration. This is because -- for an afternoon-peaking system -- as solar penetration increases, the system's peak net load shifts to later in the day -- when solar output is lower. Second, long-term planning models should determine system adequacy requirements in each time period in order to approximate LOLP calculations. Within the ReEDS model we resolve these issues by using a capacity value estimate that varies by time-slice. Within each time period the net load and shadow price on ReEDS's planning reserve constraint signals the relative importance of additional firm capacity.

Epidemiologic methods in mastitis treatment and control.

Science.gov (United States)

Thurmond, M C

1993-11-01

Methods and concepts of epidemiology offer means whereby udder health can be monitored and evaluated. Prerequisite to a sound epidemiologic approach is development of measures of mastitis that minimize biases and that account for sensitivity and specificity of diagnostic tests. Mastitis surveillance offers an ongoing and passive system for evaluation of udder health, whereas clinical and observational trials offer a more proactive and developmental approach to improving udder health.

"Epidemiological criminology": coming full circle.

Science.gov (United States)

Akers, Timothy A; Lanier, Mark M

2009-03-01

Members of the public health and criminal justice disciplines often work with marginalized populations: people at high risk of drug use, health problems, incarceration, and other difficulties. As these fields increasingly overlap, distinctions between them are blurred, as numerous research reports and funding trends document. However, explicit theoretical and methodological linkages between the 2 disciplines remain rare. A new paradigm that links methods and statistical models of public health with those of their criminal justice counterparts is needed, as are increased linkages between epidemiological analogies, theories, and models and the corresponding tools of criminology. We outline disciplinary commonalities and distinctions, present policy examples that integrate similarities, and propose "epidemiological criminology" as a bridging framework.

Epidemiological studies of radiation workers in nuclear facilities

International Nuclear Information System (INIS)

Iwai, Satoshi; Semba, Tsuyoshi; Ishida, Kenji; Takagi, Syunji; Igari, Takafumi

2017-01-01

Regarding workers at nuclear facilities, this paper described INWORKS epidemiological research published in 2015, cooperative cohort epidemiological research of IARC 15 countries 10 years before that (15-country study), and the flow of radiation epidemiological research in the period from 15-country study to INWORKS. INWORKS is a retrospective cohort study to investigate the correlation between mortality due to solid cancer, blood cancer, and cardiovascular diseases in workers in three countries of France / the U.K. / the U.S. and low dose exposure through long-term photon external exposure. It obtained the data showing the statistical significance of increased cancer death rate. However, from the subjects of the analysis, no significant evaluation was made on neutron exposure and internal exposure. Statistically significant cancer mortality was confirmed in 15-country study at low dose, low dose rate, and prolonged exposure, but significant cancer mortality rate could not be confirmed excluding Canadian data, which had problems in dose evaluation. In the epidemiological studies of cancer mortality rates of radiation workers in nuclear power industries performed in France / the U.K. / the U.S. in the period ranging from 15-country study to INWORKS, significant difference was not recognized between cancer death rate and excessive relative risk (ERR) compared with LSS epidemiological research studies that handled acute exposure. Several tasks are still remaining. (A.O.)

Challenges and Opportunities for Occupational Epidemiology in the Twenty-first Century.

Science.gov (United States)

Stayner, L T; Collins, J J; Guo, Y L; Heederik, D; Kogevinas, M; Steenland, K; Wesseling, C; Demers, P A

2017-09-01

There are many opportunities and challenges for conducting occupational epidemiologic studies today. In this paper, we summarize the discussion of a symposium held at the Epidemiology in Occupational Health (EPICOH) conference, Chicago 2014, on challenges for occupational epidemiology in the twenty-first century. The increasing number of publications and attendance at our conferences suggests that worldwide interest in occupational epidemiology has been growing. There are clearly abundant opportunities for new research in occupational epidemiology. Areas ripe for further work include developing improved methods for exposure assessment, statistical analysis, studying migrant workers and other vulnerable populations, the use of biomarkers, and new hazards. Several major challenges are also discussed such as the rapidly changing nature and location of work, lack of funding, and political/legal conflicts. As long as work exists there will be occupational diseases that demand our attention, and a need for epidemiologic studies designed to characterize these risks and to support the development of preventive strategies. Despite the challenges and given the important past contribution in this field, we are optimistic about the importance and continued vitality of the research field of occupational epidemiology.

Molecular Epidemiology of Bovine Tuberculosis and most Common ...

African Journals Online (AJOL)

Even though tuberculosis is endemic in Nigeria, information on the epidemiology of the disease especially bovine tuberculosis is still very scanty. Variable Number of Tandem Repeat (VNTR) was carried out on 113 tissue samples to have an idea of not only the epidemiology of bovine tuberculosis but also the most common ...

Has epidemiology become infatuated with methods? A historical perspective on the place of methods during the classical (1945-1965) phase of epidemiology.

Science.gov (United States)

Morabia, Alfredo

2015-03-18

Before World War II, epidemiology was a small discipline, practiced by a handful of people working mostly in the United Kingdom and in the United States. Today it is practiced by tens of thousands of people on all continents. Between 1945 and 1965, during what is known as its "classical" phase, epidemiology became recognized as a major academic discipline in medicine and public health. On the basis of a review of the historical evidence, this article examines to which extent classical epidemiology has been a golden age of an action-driven, problem-solving science, in which epidemiologists were less concerned with the sophistication of their methods than with the societal consequences of their work. It also discusses whether the paucity of methods stymied or boosted classical epidemiology's ability to convince political and financial agencies about the need to intervene in order to improve the health of the people.

Implementation of a competency-based medical education approach in public health and epidemiology training of medical students

Directory of Open Access Journals (Sweden)

Rachel Dankner

2018-02-01

Full Text Available Abstract Background There is increasing agreement among medical educators regarding the importance of improving the integration between public health and clinical education, understanding and implementation of epidemiological methods, and the ability to critically appraise medical literature. The Sackler School of Medicine at Tel-Aviv University revised its public health and preventive medicine curriculum, during 2013–2014, according to the competency-based medical education (CBME approach in training medical students. We describe the revised curriculum, which aimed to strengthen competencies in quantitative research methods, epidemiology, public health and preventive medicine, and health service organization and delivery. Methods We report the process undertaken to establish a relevant 6-year longitudinal curriculum and describe its contents, implementation, and continuous assessment and evaluation. Results Central competencies included: epidemiology and statistics for appraisal of the literature and implementation of research; the application of health promotion principles and health education strategies in disease prevention; the use of an evidence-based approach in clinical and public health decision making; the examination and analysis of disease trends at the population level; and knowledge of the structure of health systems and the role of the physician in these systems. Two new courses, in health promotion, and in public health, were added to the curriculum, and the courses in statistics and epidemiology were joined. Annual evaluation of each course results in continuous revisions of the syllabi as needed, while we continue to monitor the whole curriculum. Conclusions The described revision in a 6 year-medical school training curriculum addresses the currently identified needs in public health. Ongoing feedback from students, and re-evaluation of syllabus by courses teams are held annually. Analysis of student’s written feedbacks

The Epidemiology of Pheochromocytoma

DEFF Research Database (Denmark)

Ladefoged Ebbehøj, Andreas

2017-01-01

Pheochromocytoma and catecholamine secreting paraganglioma (PPGL) are exceedingly rare endocrine tumours, but remain a frequent diagnostic dilemma due to their potential life-threatening nature. Reliable data on the epidemiology of PPGL is lacking and no time trends in incidence rates (IR) have...

Transforming Epidemiology for 21st Century Medicine and Public Health

Science.gov (United States)

Khoury, Muin J.; Lam, Tram Kim; Ioannidis, John P.A.; Hartge, Patricia; Spitz, Margaret R.; Buring, Julie E.; Chanock, Stephen J.; Croyle, Robert T.; Goddard, Katrina A.; Ginsburg, Geoffrey S.; Herceg, Zdenko; Hiatt, Robert A.; Hoover, Robert N.; Hunter, David J.; Kramer, Barnet S.; Lauer, Michael S.; Meyerhardt, Jeffrey A.; Olopade, Olufunmilayo I.; Palmer, Julie R.; Sellers, Thomas A.; Seminara, Daniela; Ransohoff, David F.; Rebbeck, Timothy R.; Tourassi, Georgia; Winn, Deborah M.; Zauber, Ann; Schully, Sheri D.

2013-01-01

In 2012, the National Cancer Institute (NCI) engaged the scientific community to provide a vision for cancer epidemiology in the 21st century. Eight overarching thematic recommendations, with proposed corresponding actions for consideration by funding agencies, professional societies, and the research community emerged from the collective intellectual discourse. The themes are (i) extending the reach of epidemiology beyond discovery and etiologic research to include multilevel analysis, intervention evaluation, implementation, and outcomes research; (ii) transforming the practice of epidemiology by moving towards more access and sharing of protocols, data, metadata, and specimens to foster collaboration, to ensure reproducibility and replication, and accelerate translation; (iii) expanding cohort studies to collect exposure, clinical and other information across the life course and examining multiple health-related endpoints; (iv) developing and validating reliable methods and technologies to quantify exposures and outcomes on a massive scale, and to assess concomitantly the role of multiple factors in complex diseases; (v) integrating “big data” science into the practice of epidemiology; (vi) expanding knowledge integration to drive research, policy and practice; (vii) transforming training of 21st century epidemiologists to address interdisciplinary and translational research; and (viii) optimizing the use of resources and infrastructure for epidemiologic studies. These recommendations can transform cancer epidemiology and the field of epidemiology in general, by enhancing transparency, interdisciplinary collaboration, and strategic applications of new technologies. They should lay a strong scientific foundation for accelerated translation of scientific discoveries into individual and population health benefits. PMID:23462917

The failure of academic epidemiology: witness for the prosecution.

Science.gov (United States)

Shy, C M

1997-03-15

Academic epidemiology has failed to develop the scientific methods and the knowledge base to support the fundamental public health mission of preventing disease and promoting health through organized community efforts. As a basic science of public health, epidemiology should attempt to understand health and disease from a community and ecologic perspective as a consequence of how society is organized and behaves, what impact social and economic forces have on disease incidence rates, and what community actions will be effective in altering incidence rates. However, as taught in most textbooks and as widely practiced by academicians, epidemiology has become a biomedical discipline focused on the distribution and determinants of disease in groups of individuals who happen to have some common characteristics, exposures, or diseases. The ecology of human health has not been addressed, and the societal context in which disease occurs has been either disregarded or deliberately abstracted from consideration. By essentially assuming that risk factors for disease in individuals can be summed to understand the causes of disease in populations, academic epidemiology has limited itself to a narrow biomedical perspective, thereby committing the bio-medical fallacy of inferring that disease in populations can be understood by studying risk factors for disease in individuals. Epidemiology should be redefined as a study of the distribution and societal determinants of the health status of populations. This definition provides a stronger link to be the primary mission of public health and places an appropriate emphasis on the social, economic, environmental, and cultural determinants of population health. Epidemiology must cross the boundaries of other population sciences and add to its scope a macro-epidemiology, a study of causes from a truly population perspective, considering health and disease within the context of the total human environment.

Relational Capacity: Broadening the Notion of Decision-Making Capacity in Paediatric Healthcare.

Science.gov (United States)

Ruhe, Katharina M; De Clercq, Eva; Wangmo, Tenzin; Elger, Bernice S

2016-12-01

Problems arise when applying the current procedural conceptualization of decision-making capacity to paediatric healthcare: Its emphasis on content-neutrality and rational cognition as well as its implicit assumption that capacity is an ability that resides within a person jeopardizes children's position in decision-making. The purpose of the paper is to challenge this dominant account of capacity and provide an alternative for how capacity should be understood in paediatric care. First, the influence of developmental psychologist Jean Piaget upon the notion of capacity is discussed, followed by an examination of Vygostky's contextualist view on children's development, which emphasizes social interactions and learning for decision-making capacity. In drawing parallels between autonomy and capacity, substantive approaches to relational autonomy are presented that underline the importance of the content of a decision. The authors then provide a relational reconceptualization of capacity that leads the focus away from the individual to include important social others such as parents and physicians. Within this new approach, the outcome of adults' decision-making processes is accepted as a guiding factor for a good decision for the child. If the child makes a choice that is not approved by adults, the new conceptualization emphasizes mutual exchange and engagement by both parties.

Perceptions of molecular epidemiology studies of HIV among stakeholders

Directory of Open Access Journals (Sweden)

Cynthia Schairer

2017-12-01

Full Text Available Background: Advances in viral sequence analysis make it possible to track the spread of infectious pathogens, such as HIV, within a population. When used to study HIV, these analyses (i.e., molecular epidemiology potentially allow inference of the identity of individual research subjects. Current privacy standards are likely insufficient for this type of public health research. To address this challenge, it will be important to understand how stakeholders feel about the benefits and risks of such research. Design and Methods: To better understand perceived benefits and risks of these research methods, in-depth qualitative interviews were conducted with HIV-infected individuals, individuals at high-risk for contracting HIV, and professionals in HIV care and prevention. To gather additional perspectives, attendees to a public lecture on molecular epidemiology were asked to complete an informal questionnaire. Results: Among those interviewed and polled, there was near unanimous support for using molecular epidemiology to study HIV. Questionnaires showed strong agreement about benefits of molecular epidemiology, but diverse attitudes regarding risks. Interviewees acknowledged several risks, including privacy breaches and provocation of anti-gay sentiment. The interviews also demonstrated a possibility that misunderstandings about molecular epidemiology may affect how risks and benefits are evaluated. Conclusions: While nearly all study participants agree that the benefits of HIV molecular epidemiology outweigh the risks, concerns about privacy must be addressed to ensure continued trust in research institutions and willingness to participate in research.

Phlebotomine fauna, natural infection rate and feeding habits of Lutzomyia cruzi in Jaciara, state of Mato Grosso, Brazil

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Veruska Nogueira de Brito

2014-11-01

Full Text Available Visceral leishmaniasis (VL in Brazil is transmitted by the phlebotomine Lutzomyia longipalpis and in some midwestern regions by Lutzomyia cruzi. Studies of the phlebotomine fauna, feeding habits and natural infection rate by Leishmania contribute to increased understanding of the epidemiological chain of leishmaniases and their vectorial capacity. Collections were performed in Jaciara, state of Mato Grosso from 2010-2013, during which time 2,011 phlebotomines (23 species were captured (68.70% Lu. cruzi and 20.52% Lutzomyia whitmani. Lu. cruzi females were identified by observing the shapes of the cibarium (a portion of the mouthpart and spermatheca, from which samples were obtained for polymerase chain reaction to determine the rates of natural infection. Engorged phlebotomines were assessed to identify the blood-meal host by ELISA. A moderate correlation was discovered between the number of Lu. cruzi and the temperature and the minimum rate of infection was 6.10%. Twenty-two females were reactive to the antisera of bird (28%, dog (3.30% and skunk (1.60%. We conclude that Lu. cruzi and Lu. whitmani have adapted to the urban environment in this region and that Lu. cruzi is the most likely vector of VL in Jaciara. Moreover, maintenance of Leishmania in the environment is likely aided by the presence of birds and domestic and synanthropic animals.

Chancroid epidemiology in New Orleans men.

Science.gov (United States)

DiCarlo, R P; Armentor, B S; Martin, D H

1995-08-01

Epidemiologic, clinical, and microbiologic data were collected from 299 men with nonsyphilitic genital ulcer disease. One hundred eighteen (39%) were culture-positive for Haemophilus ducreyi, 57 (19%) were culture-positive for herpes simplex virus, and 124 (41%) were culture-negative. Patients with chancroid were significantly more likely than those with genital herpes to have been frequent users of alcohol (44% vs. 23%, P = .006). They were also more likely recently to have used cocaine (25% vs. 9%, P = .013), had sex with a prostitute (17% vs. 5%, P = .035), traded drugs for sex (16% vs. 2%, P = .005), and had a sex partner who used drugs (38% vs. 13%, P = .001). Culture-negative patients were similar to chancroid patients with respect to most epidemiologic risk factors. Despite the epidemiologic similarities, the clinical features of culture-negative ulcers resembled those of culture-proven herpes ulcers more closely than they did those of culture-proven chancroid ulcers. These data establish a link between chancroid in the United States and the use of crack cocaine.

Epidemiological Study of Heart Failure in China

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Yang Guo

2015-10-01

Full Text Available Heart failure (HF is a complex clinical syndrome that results from any structural or functional impairment of ventricular filling or ejection of blood. HF is one of the most important and severe end stages of many cardiovascular diseases. Epidemiological studies of HF have focused mainly on the prevalence, incidence, mortality, fatality, and distribution and temporal trends of these indicators among different populations. This review highlights important epidemiological studies of HF in China.

The French capacity mechanism

International Nuclear Information System (INIS)

2014-01-01

The French capacity mechanism has been design to ensure security of supply in the context of the energy transition. This energy transition challenges the electricity market design with several features: peak load growth, the development of renewables, demand response,... To ensure security of supply in this context, a capacity mechanism is being implemented in France. It is a market wide capacity obligation on electricity suppliers, based on market principles. Suppliers are responsible for forecasting their obligation, which corresponds to their contribution to winter peak load, and must procure enough capacity certificates to meet their obligations. Capacity certificates are granted to capacities through a certification process, which assesses their contribution to security of supply on the basis of availability commitments. This certification process is technology neutral and performance based, associated with controls and penalties in case of non compliance. Demand Side is fully integrated in the market, either through the reduction of suppliers' capacity obligation or direct participation after certification. In addition to the expected benefits in terms of security of supply, the French capacity market will foster the development of demand response. The participation of foreign capacities will require adaptations which are scheduled in a road-map, and could pave the way for further European integration of energy policies. (authors)

1995 annual epidemiologic surveillance report for Hanford Site

International Nuclear Information System (INIS)

1995-01-01

The US Department of Energy's (DOE) commitment to assuring the health and safety of its workers includes the conduct of epidemiologic surveillance activities that provide an early warning system for health problems among workers. A number of DOE sites participate in the Epidemiologic Surveillance Program. This program monitors illnesses and health conditions that result in an absence of five or more consecutive workdays, occupational injuries and illnesses, disabilities and deaths among current workers. This report provides a summary of epidemiologic surveillance data collected from the Hanford Site from January 1, 1995 through December 31, 1995. The data were collected by a coordinator at Hanford and submitted to the Epidemiologic Surveillance Data Center, located at Oak Ridge Institute for Science and Education, where quality control procedures and data analyses were carried out. The information in the main body of the report provides a descriptive analysis of the data collected from the site, and the appendices provides additional detail. The report also contains an expanded Glossary and an Explanation of Diagnostic Categories which gives examples of health conditions in each of the diagnostic categories

1995 annual epidemiologic surveillance report for Hanford Site

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-12-31

The US Department of Energy`s (DOE) commitment to assuring the health and safety of its workers includes the conduct of epidemiologic surveillance activities that provide an early warning system for health problems among workers. A number of DOE sites participate in the Epidemiologic Surveillance Program. This program monitors illnesses and health conditions that result in an absence of five or more consecutive workdays, occupational injuries and illnesses, disabilities and deaths among current workers. This report provides a summary of epidemiologic surveillance data collected from the Hanford Site from January 1, 1995 through December 31, 1995. The data were collected by a coordinator at Hanford and submitted to the Epidemiologic Surveillance Data Center, located at Oak Ridge Institute for Science and Education, where quality control procedures and data analyses were carried out. The information in the main body of the report provides a descriptive analysis of the data collected from the site, and the appendices provides additional detail. The report also contains an expanded Glossary and an Explanation of Diagnostic Categories which gives examples of health conditions in each of the diagnostic categories.

Biostatistics and epidemiology a primer for health and biomedical professionals

CERN Document Server

Wassertheil-Smoller, Sylvia

2015-01-01

Since the publication of the first edition, Biostatistics and Epidemiology has attracted loyal readers from across specialty areas in the biomedical community. Not only does this textbook teach foundations of epidemiological design and statistical methods, but it also includes topics applicable to new areas of research. Areas covered in the fourth edition include a new chapter on risk prediction, risk reclassification and evaluation of biomarkers, new material on propensity analyses, and a vastly expanded chapter on genetic epidemiology, which  is particularly relevant to those who wish to understand the epidemiological and statistical aspects of scientific articles in this rapidly advancing field. Biostatistics and Epidemiology was written to be accessible for readers without backgrounds in mathematics. It provides clear explanations of underlying principles, as well as practical guidelines of "how to do it" and "how to interpret it."a philosophical explanation of the logic of science, subsections that ...

The changing epidemiology of group B streptococcus bloodstream infection

DEFF Research Database (Denmark)

Ballard, Mark S; Schønheyder, Henrik C; Knudsen, Jenny Dahl

2016-01-01

Background Population-based studies conducted in single regions or countries have identified significant changes in the epidemiology of invasive group B streptococcus (GBS) infection. However, no studies have concurrently compared the epidemiology of GBS infections among multiple different region...

Radio-capacity of ecosystems

International Nuclear Information System (INIS)

Kultakhmedov, Yu.; Kultakhmedova-Vyshnyakova, V.

1997-01-01

This paper consider a universal approach to ecosystems of different types, based on representation of their radio-capacity. The concept of ecosystem includes reproduction of components (bio-productivity) and conditions such as maintaining of environment quality. Radio-capacity in the case of radionuclide pollution appears in accumulation and redistribution of radionuclides in the ecosystem. As a result the radionuclides are redistributed and buried in soil or lake bottom sediments. Estimation models for the radio-capacity of water and terrestrial ecosystems are represented. The calculations of the radio-capacity factor of water ecosystems are performed, and the high radio-capacity of a freshwater reservoir (F=0.6-0.8) and extremely high radio-capacity of a reservoir cascade (F c =0.99) is shown material from the Dnieper's cascade reservoirs. The methods of radio-capacity estimation of agroecosystems, wood and marine ecosystems are developed. (authors)

Acute respiratory distress syndrome: epidemiology and management approaches

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Walkey AJ

2012-07-01

Full Text Available Allan J Walkey,1 Ross Summer,1 Vu Ho,1 Philip Alkana21The Pulmonary Center, Boston University School of Medicine, Boston, MA, USA; 2Asthma Research Center, Brigham and Women's Hospital, Boston, MA, USAAbstract: Acute lung injury and the more severe acute respiratory distress syndrome represent a spectrum of lung disease characterized by the sudden onset of inflammatory pulmonary edema secondary to myriad local or systemic insults. The present article provides a review of current evidence in the epidemiology and treatment of acute lung injury and acute respiratory distress syndrome, with a focus on significant knowledge gaps that may be addressed through epidemiologic methods.Keywords: acute lung injury, acute respiratory distress syndrome, review, epidemiology

Strategic Engagement of Technical Surge Capacity for Intensified Polio Eradication Initiative in Nigeria, 2012-2015.

Science.gov (United States)

Yehualashet, Yared G; Mkanda, Pascal; Gasasira, Alex; Erbeto, Tesfaye; Onimisi, Anthony; Horton, Janet; Banda, Richard; Tegegn, Sisay G; Ahmed, Haruna; Afolabi, Oluwole; Wadda, Alieu; Vaz, Rui G; Nsubuga, Peter

2016-05-01

Following the 65th World Health Assembly (WHA) resolution on intensification of the Global Poliomyelitis Eradication Initiative (GPEI), the Nigerian government, with support from the World Health Organization (WHO) and other partners, implemented a number of innovative strategies to curb the transmission of wild poliovirus (WPV) in the country. One of the innovations successfully implemented since mid 2012 is the WHO's engagement of surge capacity personnel. The WHO reorganized its functional structure, adopted a transparent recruitment and deployment process, provided focused technical and management training, and applied systematic accountability framework to successfully manage the surge capacity project in close collaboration with the national counterparts and partners. The deployment of the surge capacity personnel was guided by operational and technical requirement analysis. Over 2200 personnel were engaged, of whom 92% were strategically deployed in 11 states classified as high risk on the basis of epidemiological risk analysis and compromised security. These additional personnel were directly engaged in efforts aimed at improving the performance of polio surveillance, vaccination campaigns, increased routine immunization outreach sessions, and strengthening partnership with key stakeholders at the operational level, including community-based organizations. Programmatic interventions were sustained in states in which security was compromised and the risk of polio was high, partly owing to the presence of the surge capacity personnel, who are engaged from the local community. Since mid-2012, significant programmatic progress was registered in the areas of polio supplementary immunization activities, acute flaccid paralysis surveillance, and routine immunization with the support of the surge capacity personnel. As of 19 June 2015, the last case of WPV was reported on 24 July 2014. The surge infrastructure has also been instrumental in building local capacity

Molecular Epidemiology of Brucella abortus in Northern Ireland-1991 to 2012.

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Adrian Allen

Full Text Available Brucellosis is the most common bacterial zoonoses worldwide. Bovine brucellosis caused by Brucella abortus has far reaching animal health and economic impacts at both the local and national levels. Alongside traditional veterinary epidemiology, the use of molecular typing has recently been applied to inform on bacterial population structure and identify epidemiologically-linked cases of infection. Multi-locus variable number tandem repeat VNTR analysis (MLVA was used to investigate the molecular epidemiology of a well-characterised Brucella abortus epidemic in Northern Ireland involving 387 herds between 1991 and 2012.MLVA identified 98 unique B. abortus genotypes from disclosing isolates in the 387 herds involved in the epidemic. Clustering algorithms revealed the relatedness of many of these genotypes. Combined with epidemiological information on chronology of infection and geographic location, these genotype data helped to identify 7 clonal complexes which underpinned the outbreak over the defined period. Hyper-variability of some VNTR loci both within herds and individual animals led to detection of multiple genotypes associated with single outbreaks. However with dense sampling, these genotypes could still be associated with specific clonal complexes thereby permitting inference of epidemiological links. MLVA- based epidemiological monitoring data were congruent with an independent classical veterinary epidemiology study carried out in the same territory.MLVA is a useful tool in ongoing disease surveillance of B. abortus outbreaks, especially when combined with accurate epidemiological information on disease tracings, geographical clustering of cases and chronology of infection.

Cocoa Polyphenols: Evidence from Epidemiological Studies.

Science.gov (United States)

Matsumoto, Chisa

2018-01-01

Accumulating evidence suggests potential preventive effects of chocolate/cocoa on the risk of cardio vascular disease (CVD). However, cocoa products also contain high levels of sugar and fat, which increase CVD risk factors. Even, the identity of the substance in chocolate/cocoa that has a favorable effect on CVD and CVD risk factors remains unclear, growing evidence from experimental studies suggests that cocoa polyphenols might be a major contributor to cardiovascular-protective effects. However, epidemiological studies, which are necessary to evaluate an association between the risk of CVD and cocoa polyphenol, remain sparse. We will discuss recent evidence regarding the association between cocoa polyphenol consumption and the risks of CVD and its risk factors by reviewing recent epidemiological studies. We shall also provide some guidance for patient counseling and will discuss the public health implications for recommending cocoa polyphenol consumption to prevent CVD. Epidemiological studies evaluating the association between cocoa polyphenol itself and the risk of CVD are sparse. However, evidence from limited epidemiological studies suggests that cocoa polyphenol consumption may lower the risk of CVD. Given the potential adverse effects of the consumption of cocoa products with high fat and sugar and the fact that the most appropriate dose of cocoa polyphenol for cardio-protective effects has not yet been established, health care providers should remain cautious about recommending cocoa/cocoa polyphenol consumption to their patients to reduce the risk of CVD, taking the characteristics of individual patients into careful consideration. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

The epidemiology of HIV infection in Morocco: systematic review and data synthesis

Science.gov (United States)

Kouyoumjian, S P; Mumtaz, G R; Hilmi, N; Zidouh, A; El Rhilani, H; Alami, K; Bennani, A; Gouws, E; Ghys, P D; Abu-Raddad, L J

2013-01-01

Summary Morocco has made significant strides in building its HIV research capacity. Based on a wealth of empirical data, the objective of this study was to conduct a comprehensive and systematic literature review and analytical synthesis of HIV epidemiological evidence in this country. Data were retrieved using three major sources of literature and data. HIV transmission dynamics were found to be focused in high-risk populations, with female sex workers (FSWs) and clients contributing the largest share of new HIV infections. There is a pattern of emerging epidemics among some high-risk populations, and some epidemics, particularly among FSWs, appear to be established and stable. The scale of the local HIV epidemics and populations affected show highly heterogeneous geographical distribution. To optimize the national HIV response, surveillance and prevention efforts need to be expanded among high-risk populations and in geographic settings where low intensity and possibly concentrated HIV epidemics are emerging or are already endemic. PMID:23970764

Genomic Resources for Cancer Epidemiology

Science.gov (United States)

This page provides links to research resources, complied by the Epidemiology and Genomics Research Program, that may be of interest to genetic epidemiologists conducting cancer research, but is not exhaustive.

Epidemiology of subtypes of depression

DEFF Research Database (Denmark)

Kessing, L V

2007-01-01

depression, dysthymia, and subsyndromal states; the association between stressful life events and depression appears to diminish with the number of depressive episodes. Finally, recent genetic findings are congruent with a model indicating that the majority of depressions develop in the interplay between...... genes and stressful experiences, whereas 'reactive' depressions and 'endogenous' depressions apparently exist at a lower prevalence. CONCLUSION: Further longitudinal, analytical, and genetic epidemiologic studies are needed to reveal which conditions are mild and transient, and which may be precursors......OBJECTIVE: There is a general clinical impression that depression differs qualitatively from non-depressive conditions, and that it can be identified as a categorical entity. In contrast, epidemiological studies support the view that depression is dynamic in nature and develops on a continuous...

Direct progeny detection techniques and random epidemiology

International Nuclear Information System (INIS)

Mayya, Y.S.; Mishra, Rosaline; Sapra, B.K.

2015-01-01

Over the past 40 years, there has been considerable progress in the measurements methods and their application to the estimates of risks due to radon among general populations. The previous decade saw major development in this regard. It was the direct estimate of indoor radon risk from epidemiological studies in Europe and North America. These were important findings that demonstrated the presence of lung cancer risks at residential radon levels supplementing the generally used risks estimates at high exposures obtained from uranium miner's data. The residential radon epidemiological studies largely used radon concentration as a measure of exposure. The exposure to decay products, which are primarily the dose givers, are assumed to be proportional to the measured gas concentrations. Also, the presence of thoron was neglected in these studies. Although several corrections have appeared to these assessments, the question of variability of actual decay product exposures has largely remained unaddressed. In order to circumvent this limitation, passive techniques were developed to estimate the decay product concentrations directly using deposition monitors. These are based on detecting the alpha particles from decay products deposited on an absorber mounted LR-115 detectors. Known as Direct radon, and Thoron Progeny sensors (DRPS/DTPS), these have been further refined to separate fine fraction from the coarse fraction by wire-mesh capping techniques. Large number environmental calibration exercises and field data generation has been carried out on the progeny concentrations in Indian and some European environments. The development of progeny sensors offers a new tool for future epidemiology. Since in the Indian context, there exist no radon related epidemiological estimates of risk, it is time one conducts large scale studies to seek possible correlations between DRPS/DTPS data and lung cancer risks. While epidemiological studies in High background radiation areas

It is time to abandon "expected bladder capacity." Systematic review and new models for children's normal maximum voided volumes.

Science.gov (United States)

Martínez-García, Roberto; Ubeda-Sansano, Maria Isabel; Díez-Domingo, Javier; Pérez-Hoyos, Santiago; Gil-Salom, Manuel

2014-09-01

There is an agreement to use simple formulae (expected bladder capacity and other age based linear formulae) as bladder capacity benchmark. But real normal child's bladder capacity is unknown. To offer a systematic review of children's normal bladder capacity, to measure children's normal maximum voided volumes (MVVs), to construct models of MVVs and to compare them with the usual formulae. Computerized, manual and grey literature were reviewed until February 2013. Epidemiological, observational, transversal, multicenter study. A consecutive sample of healthy children aged 5-14 years, attending Primary Care centres with no urologic abnormality were selected. Participants filled-in a 3-day frequency-volume chart. Variables were MVVs: maximum of 24 hr, nocturnal, and daytime maximum voided volumes. diuresis and its daytime and nighttime fractions; body-measure data; and gender. The consecutive steps method was used in a multivariate regression model. Twelve articles accomplished systematic review's criteria. Five hundred and fourteen cases were analysed. Three models, one for each of the MVVs, were built. All of them were better adjusted to exponential equations. Diuresis (not age) was the most significant factor. There was poor agreement between MVVs and usual formulae. Nocturnal and daytime maximum voided volumes depend on several factors and are different. Nocturnal and daytime maximum voided volumes should be used with different meanings in clinical setting. Diuresis is the main factor for bladder capacity. This is the first model for benchmarking normal MVVs with diuresis as its main factor. Current formulae are not suitable for clinical use. © 2013 Wiley Periodicals, Inc.

Systematic reviews of epidemiology in diabetes: finding the evidence

Directory of Open Access Journals (Sweden)

Waugh Norman

2005-01-01

Full Text Available Abstract Background Methodological research to support searching for those doing systematic reviews of epidemiological studies is a relatively neglected area. Our aim was to determine how many databases it is necessary to search to ensure a comprehensive coverage of the literature in diabetes epidemiology, with the aim of examining the efficiency of searching in support of systematic reviews of the epidemiology of diabetes Methods Three approaches were used. First, we defined a set of English language diabetes journals and examined their coverage in bibliographic databases. Second, we searched extensively for diabetes epidemiology articles (in all languages to determine which are the most useful databases; and third, we analysed the scattering of these articles to determine the core journals in the area. Results The overlap between MEDLINE and Embase for diabetes journals was 59%. A search for diabetes epidemiology articles across both MEDLINE and Embase, showed that MEDLINE alone retrieved about 94% of the total articles. Searching for diabetes epidemiology studies beyond MEDLINE and Embase retrieved no additional English language journal articles. The only diabetes epidemiology studies found by searching beyond MEDLINE and Embase were found in LILACS, and were Spanish or Portuguese language studies from Latin America; no additional English language studies were found. Only 30% of the meeting abstracts were converted to full publication after three years. One third of journal articles were published in just six journals, with Diabetes Care contributing 14.3% of the articles, followed by Diabetic Medicine (5.0%; Diabetes Research & Clinical Practice (4.1%; Diabetologia (4.0%; Diabetes & Metabolism (2.4% and Diabetes (2.0%. Conclusions Our results show that when searching for articles on diabetes epidemiology, MEDLINE and Embase would suffice for English language papers, with LILACS giving some additional non-English articles from Latin America

Capacity Bounds and High-SNR Capacity of MIMO Intensity-Modulation Optical Channels

KAUST Repository

Chaaban, Anas

2018-02-19

The capacity of the intensity modulation direct detection multiple-input multiple-output channel is studied. Therein, the nonnegativity constraint of the transmit signal limits the applicability of classical schemes, including precoding. Thus, new ways are required for deriving capacity bounds for this channel. To this end, capacity lower bounds are developed in this paper by deriving the achievable rates of two precodingfree schemes: Channel inversion and QR decomposition. The achievable rate of a DC-offset SVD-based scheme is also derived as a benchmark. Then, capacity upper bounds are derived and compared against the lower bounds. As a result, the capacity at high signal-to-noise ratio (SNR) is characterized for the case where the number of transmit apertures is not larger than the number of receive apertures, and is shown to be achievable by the QR decomposition scheme. This is shown for a channel with average intensity or peak intensity constraints. Under both constraints, the high-SNR capacity is approximated within a small gap. Extensions to a channel with more transmit apertures than receive apertures are discussed, and capacity bounds for this case are derived.

Capacity Bounds and High-SNR Capacity of MIMO Intensity-Modulation Optical Channels

KAUST Repository

Chaaban, Anas; Rezki, Zouheir; Alouini, Mohamed-Slim

2018-01-01

The capacity of the intensity modulation direct detection multiple-input multiple-output channel is studied. Therein, the nonnegativity constraint of the transmit signal limits the applicability of classical schemes, including precoding. Thus, new ways are required for deriving capacity bounds for this channel. To this end, capacity lower bounds are developed in this paper by deriving the achievable rates of two precodingfree schemes: Channel inversion and QR decomposition. The achievable rate of a DC-offset SVD-based scheme is also derived as a benchmark. Then, capacity upper bounds are derived and compared against the lower bounds. As a result, the capacity at high signal-to-noise ratio (SNR) is characterized for the case where the number of transmit apertures is not larger than the number of receive apertures, and is shown to be achievable by the QR decomposition scheme. This is shown for a channel with average intensity or peak intensity constraints. Under both constraints, the high-SNR capacity is approximated within a small gap. Extensions to a channel with more transmit apertures than receive apertures are discussed, and capacity bounds for this case are derived.

Epidemiology, molecular epidemiology, and risk factors for renal cell carcinoma

Directory of Open Access Journals (Sweden)

Chiara Paglino

2011-12-01

Full Text Available Despite only accounting for approximately 2% of all new primary cancer cases, renal cell carcinoma (RCC incidence has dramatically increased over time. Incidence rates vary greatly according to geographic areas, so that it is extremely likely that exogenous risk factors could play an important role in the development of this cancer. Several risk factors have been linked with RCC, including cigarette smoking, obesity, hypertension (and antihypertensive drugs, chronic kidney diseases (also dialysis and transplantation, as well as the use of certain analgesics. Furthermore, although RCC has not generally been considered an occupational cancer, several types of occupationally-derived exposures have been implicated in its pathogenesis. These include exposure to asbestos, chlorinated solvents, gasoline, diesel exhaust fumes, polycyclic aromatic hydrocarbons, printing inks and dyes, cadmium and lead. Finally, families with a predisposition to the development of renal neoplasms were identified and the genes involved discovered and characterized. Therefore, there are now four well-characterized, genetically determined syndromes associated with an increased incidence of kidney tumors, i.e., Von Hippel Lindau (VHL, Hereditary Papillary Renal Carcinoma (HPRC, Birt-Hogg-Dubé Syndrome (BHD, and Hereditary Leiomyomatosis and Renal Cell Cancer (HLRCC. This review will address present knowledge about the epidemiology, molecular epidemiology and risk factors of RCC.

Epidemiology of Patellar Tendinopathy in Elite Male Soccer Players

NARCIS (Netherlands)

Hägglund, Martin; Zwerver, Johannes; Ekstrand, Jan

Background: Patellar tendinopathy is common among athletes in jumping sports and in sports with prolonged repetitive stress of the knee extensor apparatus. The epidemiology in soccer is not well described. Purpose: This study was undertaken to investigate and describe the epidemiology of patellar

Metabolomics and Epidemiology Working Group

Science.gov (United States)

The Metabolomics and Epidemiology (MetEpi) Working Group promotes metabolomics analyses in population-based studies, as well as advancement in the field of metabolomics for broader biomedical and public health research.

Standard epidemiological methods to understand and improve Apis mellifera health

OpenAIRE

Lengerich, Eugene; Spleen, Angela; Dainat, Benjamin; Cresswell, James; Baylis , Kathy; Nguyen, Bach Kim; Soroker, Victoria; Underwood, Robyn; Human, Hannelie; Le Conte, Yves; Saegerman, Claude

2013-01-01

In this paper, we describe the use of epidemiological methods to understand and reduce honey bee morbidity and mortality. Essential terms are presented and defined and we also give examples for their use. Defining such terms as disease, population, sensitivity, and specificity, provides a framework for epidemiological comparisons. The term population, in particular, is quite complex for an organism like the honey bee because one can view “epidemiological unit” as individual bees, colonies, ap...

Epidemiology of low back pain.

Science.gov (United States)

Skovron, M L

1992-10-01

At present, although there have been many epidemiological studies of risk factors for low back pain, there are few risk factors established in prospective studies; and our understanding of them remains relatively crude. Individuals in jobs requiring manual materials handling, particularly repeated heavy lifting and lifting while twisting, are at increased risk of back pain leading to work absence. In addition, exposure to whole-body vibration and job requirements for static postures are associated with back pain. Individual trunk strength has not been consistently demonstrated as associated with back pain; although there is some suggestion that when work requirements for heavy lifting exceed individual capacities, back pain is more likely to occur. The pattern of peak age at onset in the 20's is consistent with back pain development early in working life. Among other individual characteristics, only cigarette smoking has consistently been associated with back pain; and the biological mechanism for this finding is not understood. Evidence with respect to spinal flexibility, aerobic capacity, educational attainment and other variables is suggestive but not consistent. There is some evidence that the individual's relation to work, expressed as job satisfaction or supervisor rating, is also related to work absence due to back pain. While it is possible to describe, however crudely, the characteristics placing people at risk for back pain leading to work absence and/or medical attention, the problem of predicting chronicity and thus identifying patients for more intensive clinical intervention remains unresolved. At this time, only age of the patient and certain clinical features of the back pain such as the presence of sciatic symptoms, duration of the current episode, and history of prior episodes are consistently demonstrated predictors. In chronic patients, there is suggestive evidence that spinal flexibility, trunk strength, and certain psychological

Association Between Cannabis and Psychosis: Epidemiologic Evidence.

Science.gov (United States)

Gage, Suzanne H; Hickman, Matthew; Zammit, Stanley

2016-04-01

Associations between cannabis use and psychotic outcomes are consistently reported, but establishing causality from observational designs can be problematic. We review the evidence from longitudinal studies that have examined this relationship and discuss the epidemiologic evidence for and against interpreting the findings as causal. We also review the evidence identifying groups at particularly high risk of developing psychosis from using cannabis. Overall, evidence from epidemiologic studies provides strong enough evidence to warrant a public health message that cannabis use can increase the risk of psychotic disorders. However, further studies are required to determine the magnitude of this effect, to determine the effect of different strains of cannabis on risk, and to identify high-risk groups particularly susceptible to the effects of cannabis on psychosis. We also discuss complementary epidemiologic methods that can help address these questions. Copyright © 2016 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

Ethics, big data and computing in epidemiology and public health.

Science.gov (United States)

Salerno, Jennifer; Knoppers, Bartha M; Lee, Lisa M; Hlaing, WayWay M; Goodman, Kenneth W

2017-05-01

This article reflects on the activities of the Ethics Committee of the American College of Epidemiology (ACE). Members of the Ethics Committee identified an opportunity to elaborate on knowledge gained since the inception of the original Ethics Guidelines published by the ACE Ethics and Standards of Practice Committee in 2000. The ACE Ethics Committee presented a symposium session at the 2016 Epidemiology Congress of the Americas in Miami on the evolving complexities of ethics and epidemiology as it pertains to "big data." This article presents a summary and further discussion of that symposium session. Three topic areas were presented: the policy implications of big data and computing, the fallacy of "secondary" data sources, and the duty of citizens to contribute to big data. A balanced perspective is needed that provides safeguards for individuals but also furthers research to improve population health. Our in-depth review offers next steps for teaching of ethics and epidemiology, as well as for epidemiological research, public health practice, and health policy. To address contemporary topics in the area of ethics and epidemiology, the Ethics Committee hosted a symposium session on the timely topic of big data. Technological advancements in clinical medicine and genetic epidemiology research coupled with rapid advancements in data networks, storage, and computation at a lower cost are resulting in the growth of huge data repositories. Big data increases concerns about data integrity; informed consent; protection of individual privacy, confidentiality, and harm; data reidentification; and the reporting of faulty inferences. Copyright © 2017 Elsevier Inc. All rights reserved.

Heat Capacity Analysis Report

International Nuclear Information System (INIS)

Findikakis, A.

2004-01-01

The purpose of this report is to provide heat capacity values for the host and surrounding rock layers for the waste repository at Yucca Mountain. The heat capacity representations provided by this analysis are used in unsaturated zone (UZ) flow, transport, and coupled processes numerical modeling activities, and in thermal analyses as part of the design of the repository to support the license application. Among the reports that use the heat capacity values estimated in this report are the ''Multiscale Thermohydrologic Model'' report, the ''Drift Degradation Analysis'' report, the ''Ventilation Model and Analysis Report, the Igneous Intrusion Impacts on Waste Packages and Waste Forms'' report, the ''Dike/Drift Interactions report, the Drift-Scale Coupled Processes (DST and TH Seepage) Models'' report, and the ''In-Drift Natural Convection and Condensation'' report. The specific objective of this study is to determine the rock-grain and rock-mass heat capacities for the geologic stratigraphy identified in the ''Mineralogic Model (MM3.0) Report'' (BSC 2004 [DIRS 170031], Table 1-1). This report provides estimates of the heat capacity for all stratigraphic layers except the Paleozoic, for which the mineralogic abundance data required to estimate the heat capacity are not available. The temperature range of interest in this analysis is 25 C to 325 C. This interval is broken into three separate temperature sub-intervals: 25 C to 95 C, 95 C to 114 C, and 114 C to 325 C, which correspond to the preboiling, trans-boiling, and postboiling regimes. Heat capacity is defined as the amount of energy required to raise the temperature of a unit mass of material by one degree (Nimick and Connolly 1991 [DIRS 100690], p. 5). The rock-grain heat capacity is defined as the heat capacity of the rock solids (minerals), and does not include the effect of water that exists in the rock pores. By comparison, the rock-mass heat capacity considers the heat capacity of both solids and pore

Statistical Reasoning and Methods in Epidemiology to Promote Individualized Health: In Celebration of the 100th Anniversary of the Johns Hopkins Bloomberg School of Public Health.

Science.gov (United States)

Ogburn, Elizabeth L; Zeger, Scott L

2016-03-01

Epidemiology is concerned with determining the distribution and causes of disease. Throughout its history, epidemiology has drawn upon statistical ideas and methods to achieve its aims. Because of the exponential growth in our capacity to measure and analyze data on the underlying processes that define each person's state of health, there is an emerging opportunity for population-based epidemiologic studies to influence health decisions made by individuals in ways that take into account the individuals' characteristics, circumstances, and preferences. We refer to this endeavor as "individualized health." The present article comprises 2 sections. In the first, we describe how graphical, longitudinal, and hierarchical models can inform the project of individualized health. We propose a simple graphical model for informing individual health decisions using population-based data. In the second, we review selected topics in causal inference that we believe to be particularly useful for individualized health. Epidemiology and biostatistics were 2 of the 4 founding departments in the world's first graduate school of public health at Johns Hopkins University, the centennial of which we honor. This survey of a small part of the literature is intended to demonstrate that the 2 fields remain just as inextricably linked today as they were 100 years ago. © The Author 2016. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Biomarkers in Prostate Cancer Epidemiology

Directory of Open Access Journals (Sweden)

Mudit Verma

2011-09-01

Full Text Available Understanding the etiology of a disease such as prostate cancer may help in identifying populations at high risk, timely intervention of the disease, and proper treatment. Biomarkers, along with exposure history and clinical data, are useful tools to achieve these goals. Individual risk and population incidence of prostate cancer result from the intervention of genetic susceptibility and exposure. Biochemical, epigenetic, genetic, and imaging biomarkers are used to identify people at high risk for developing prostate cancer. In cancer epidemiology, epigenetic biomarkers offer advantages over other types of biomarkers because they are expressed against a person’s genetic background and environmental exposure, and because abnormal events occur early in cancer development, which includes several epigenetic alterations in cancer cells. This article describes different biomarkers that have potential use in studying the epidemiology of prostate cancer. We also discuss the characteristics of an ideal biomarker for prostate cancer, and technologies utilized for biomarker assays. Among epigenetic biomarkers, most reports indicate GSTP1 hypermethylation as the diagnostic marker for prostate cancer; however, NKX2-5, CLSTN1, SPOCK2, SLC16A12, DPYS, and NSE1 also have been reported to be regulated by methylation mechanisms in prostate cancer. Current challenges in utilization of biomarkers in prostate cancer diagnosis and epidemiologic studies and potential solutions also are discussed.

Panel 1: Epidemiology and Diagnosis.

Science.gov (United States)

Homøe, Preben; Kværner, Kari; Casey, Janet R; Damoiseaux, Roger A M J; van Dongen, Thijs M A; Gunasekera, Hasantha; Jensen, Ramon G; Kvestad, Ellen; Morris, Peter S; Weinreich, Heather M

2017-04-01

Objective To create a literature review between 2011 and June 1, 2015, on advances in otitis media (OM) epidemiology and diagnosis (including relevant audiology studies). Data Sources Electronic search engines (PubMed, EMBASE, and Cochrane Library) with a predefined search strategy. Review Methods Articles with appropriate epidemiologic methodology for OM, including acute mastoiditis and eustachian tube dysfunction. Items included OM worldwide and in high-risk populations, OM-related hearing loss, news in OM diagnostics, prenatal risk factors and comorbidities, postnatal risk factors, genetics, microbiological epidemiology, guidelines, and quality of life. Conclusions Diagnostic evidence and genetic studies are increasing; guidelines are introduced worldwide; and there is evidence of benefit of pneumococcal conjugate vaccines. New risk factors and comordities are identified in the study period, and quality of life is affected in children and their families. Implications for Practice Chronic suppurative OM occurs worldwide and contributes to lifelong hearing loss. Uniform definitions are still lacking and should be provided. An association between HIV and chronic suppurative OM has been found. Tympanometry is recommended for diagnosis, with or without pneumatic otoscopy. Video otoscopy, algorithms, and validated questionnaires may assist clinicians. Childhood obesity is associated with OM. Heritability accounts for 20% to 50% of OM diagnoses. OM-prone children seem to produce weaker immunologic responses to pneumococcal conjugate vaccines. Clinicians tend to individualize treatment without adhering to guidelines.

Policy Capacity Meets Politics: Comment on "Health Reform Requires Policy Capacity".

Science.gov (United States)

Fafard, Patrick

2015-07-22

It is difficult to disagree with the general argument that successful health reform requires a significant degree of policy capacity or that all players in the policy game need to move beyond self-interested advocacy. However, an overly broad definition of policy capacity is a problem. More important perhaps, health reform inevitably requires not just policy capacity but political leadership and compromise. © 2015 by Kerman University of Medical Sciences.

The acropetal effects of indole-3-acetic acid in isolated shoot segments of Acer pseudoplatanus L. II. Possible regulation by a vectorial fieid of auxin waves

Directory of Open Access Journals (Sweden)

Jacek A. Adamczyk

2014-01-01

Full Text Available The acropetal effects of auxin on elongation of axillary buds and on modulation of the wave-like pattern of basipetal efflux of natural auxin to agar from Acer pseudoplatanus L. shoots were studied. When synthetic IAA was applied to cut surfaces of one of two branches the elongation growth of buds situated on the opposite branch was retarded, suggesting regulation independent of the direct action of the molecules of the applied IAA. Oscillations in basipetal transport of natural auxin along the stem segments were observed corroborating the results of other authors using different tree species. Apical application of synthetic IAA for 1 hour to the lateral branch caused a phase shift of the wave-like pattern of basipetal efflux of natural auxin, when the stem segment above the treated branch was sectioned. The same effect was observed evoked by the laterally growing branch which is interpreted as an effect of natural auxin produced by the actively growing shoot. These modulations could be propagated acropetally at a rate excluding direct action of auxin molecules at the sites of measurement. The results seem to corroborate the hypothesis suggesting that auxin is involved in acropetal regulation of shoot apex growth through its effect upon modulation of the vectorial field which arises when the auxin-waves translocate in cambium.

The epidemiology and control of onchocerciasis in West-Africa

NARCIS (Netherlands)

J.H.F. Remme

1989-01-01

textabstractThe present thesis deals with research which has been undertaken since 1983 with the aim of finding answers to the three main epidemiological questions which have been discussed above, i.e. I.-What are the epidemiological patterns of ocular onchocerciasis in West Africa and what is

Epidemiology of injuries in female high school soccer players ...

African Journals Online (AJOL)

Background: Sport is a compulsory activity in schools in South Africa. Female learners participating in soccer are more vulnerable to injuries than males. Objective: This study determined the epidemiology of injuries in female high school soccer players. Methods: A cross sectional survey captured the epidemiology of ...

The role of laboratory confirmations and molecular epidemiology in ...

African Journals Online (AJOL)

This review reports on the role of laboratory confirmation and molecular epidemiology in global eradication of measles. The role of laboratory confirmation and molecular epidemiology in defining the origins of measles outbreaks cannot be overemphasized. New serological tests based on recombinant proteins detect only a ...

Epidemiology of Postherpetic Neuralgia in Korea

Science.gov (United States)

Hong, Myong-Joo; Kim, Yeon-Dong; Cheong, Yong-Kwan; Park, Seon-Jeong; Choi, Seung-Won; Hong, Hyon-Joo

2016-01-01

Abstract Postherpetic neuralgia (PHN) is a disease entity defined as persistent pain after the acute pain of herpes zoster gradually resolves. It is associated with impaired daily activities, resulting in reduced quality of life. General epidemiological data on PHN is necessary for the effective management. However, data on the epidemiology of PHN in Korea is lacking. The aim of this study was to evaluate the epidemiological features of PHN in the general population. We used population-based medical data for 51,448,491 subscribers to the Health Insurance Service in the year of 2013 to analyze of PHN epidemiology in Korea, such as the incidence, regional distribution, seasonal variation, and healthcare resource utilization. Total number of patients and medical cost on PHN were analyzed from 2009 to 2013. Findings indicate that the incidence of PHN in Korea was 2.5 per 1000 person-years, which was strongly correlated with age and sex. There were no differences in seasonal variation or regional distribution. The medical cost increased steadily over the study period. When admitted to general hospitals, patients with PHN were mainly managed in the dermatology and anesthesiology departments. The incidence and prevalence rates of PHN in Koreans appear to be considerably higher compared to those in western populations, while the sex and age predisposition was similar. Considering that the pain associated with PHN can have a marked impact on a patient's quality of life resulting in a medicosocial economic burden, anesthesiology physicians have an important role in primary care in Korea. Future research on the cost-effectiveness of the management of PHN is needed. PMID:27057902

Methodologic assessment of radiation epidemiology studies

International Nuclear Information System (INIS)

Beebe, G.W.

1983-01-01

Epidemiologic studies of the late effects of ionizing radiation have utilized the entire spectrum of situations in which man has been exposed. These studies have provided insights into the dependence of human effects upon not only dose to target tissues but also other dimensions of exposure, host characteristics, and time following exposure. Over the past three decades studies have progressed from the mere identification of effects to their measurement. Because investigators of human effects have no control over the exposure situation, validity must be sought in the consistency of findings among independent studies and with accepted biologic principles. Because exposure may be confounded with factors that are hidden from view, bias may enter into any study of human exposure. Avoidance of bias and attainment of sufficient power to detect relationships that are real are methodologic challenges. Many methodologic issues, e.g., those associated with the definition and measurement of specific end-points, or with the selection of appropriate controls, permeate epidemiologic work in all fields. Others, especially those concerned with the measurement of exposure, the patterning of events in time after exposure, and the prediction of events beyond the scope of existing observations give radiation epidemiology its distinctive character

The Changing Epidemiology of Autism Spectrum Disorders.

Science.gov (United States)

Lyall, Kristen; Croen, Lisa; Daniels, Julie; Fallin, M Daniele; Ladd-Acosta, Christine; Lee, Brian K; Park, Bo Y; Snyder, Nathaniel W; Schendel, Diana; Volk, Heather; Windham, Gayle C; Newschaffer, Craig

2017-03-20

Autism spectrum disorder (ASD) is a complex neurodevelopmental condition with lifelong impacts. Genetic and environmental factors contribute to ASD etiology, which remains incompletely understood. Research on ASD epidemiology has made significant advances in the past decade. Current prevalence is estimated to be at least 1.5% in developed countries, with recent increases primarily among those without comorbid intellectual disability. Genetic studies have identified a number of rare de novo mutations and gained footing in the areas of polygenic risk, epigenetics, and gene-by-environment interaction. Epidemiologic investigations focused on nongenetic factors have established advanced parental age and preterm birth as ASD risk factors, indicated that prenatal exposure to air pollution and short interpregnancy interval are potential risk factors, and suggested the need for further exploration of certain prenatal nutrients, metabolic conditions, and exposure to endocrine-disrupting chemicals. We discuss future challenges and goals for ASD epidemiology as well as public health implications.

Web tools for molecular epidemiology of tuberculosis.

Science.gov (United States)

Shabbeer, Amina; Ozcaglar, Cagri; Yener, Bülent; Bennett, Kristin P

2012-06-01

In this study we explore publicly available web tools designed to use molecular epidemiological data to extract information that can be employed for the effective tracking and control of tuberculosis (TB). The application of molecular methods for the epidemiology of TB complement traditional approaches used in public health. DNA fingerprinting methods are now routinely employed in TB surveillance programs and are primarily used to detect recent transmissions and in outbreak investigations. Here we present web tools that facilitate systematic analysis of Mycobacterium tuberculosis complex (MTBC) genotype information and provide a view of the genetic diversity in the MTBC population. These tools help answer questions about the characteristics of MTBC strains, such as their pathogenicity, virulence, immunogenicity, transmissibility, drug-resistance profiles and host-pathogen associativity. They provide an integrated platform for researchers to use molecular epidemiological data to address current challenges in the understanding of TB dynamics and the characteristics of MTBC. Copyright © 2011. Published by Elsevier B.V.

Capacity competition in electricity markets

International Nuclear Information System (INIS)

Crampes, Claude; Creti, Anna

2005-01-01

The article analyzed a two-stage game where capacity constrained electricity generators first choose how much capacity they make available and then compete in a uniform-rice auction. It is studied how capacity withholding can be used strategically to enforce market power and how uniform auctions in the price game change the results of capacity constrained competition models. The uniform auction procedure gives strong incentives to capacity restriction. At equilibrium, however, power shortage never occurs. Though auctions in electricity markets have already been studied by several economists, yet an important feature of spot trading is the capacity availability decision. In fact, for technical reasons, such as equipment maintenance or failures, the installed capacity may not work at maximum operating level and the spot market rules oblige generators to announce which plants they are willing to use and simultaneously their offer prices. Beside technical reasons, the so-called 'capacity declarations' also offer a strategic instrument for firms: by restricting capacity, operators can benefit from scarcity rents. Assessing whether generators withhold capacity is an intriguing issue for real electricity markets, though proving it is a difficult task. Several theoretical papers show that generators are able to keep wholesale prices high as compared to their generation costs. In our model, a generator is not obliged to declare all installed capacity as available, but decides on the amount of MW of electricity that is available. Hence the available capacity is an endogenous variable while the installed one is exogenous. The distinction between installed capacities and 'available' capacities allows to explain clearly whether generators exert market power by declaring unavailable some production units. Although we find multiple sub game perfect equilibria that cannot be eliminated by Pareto-dominance, all the outcomes are characterized by market price at the highest

Epidemiology, public health, and the rhetoric of false positives

DEFF Research Database (Denmark)

Blair, Aaron; Saracci, Rodolfo; Vineis, Paolo

2009-01-01

BACKGROUND: As an observational science, epidemiology is regarded by some researchers as inherently flawed and open to false results. In a recent paper, Boffetta et al. [Boffetta P, McLaughlin JK, LaVecchia C, Tarone RE, Lipworth L, Blot WJ. False-positive results in cancer epidemiology: a plea f...

Integrated capacity and inventory management with capacity acquisition lead times

NARCIS (Netherlands)

Mincsovics, G.Z.; Tan, T.; Alp, O.

2009-01-01

We model a make-to-stock production system that utilizes permanent and contingent capacity to meet non-stationary stochastic demand, where a constant lead time is associated with the acquisition of contingent capacity. We determine the structure of the optimal solution concerning both the

La eco-epidemiología retrospectiva como herramienta aplicada a la vigilancia de la leishmaniasis en Misiones, Argentina, 1920-2014

Directory of Open Access Journals (Sweden)

Oscar Daniel Salomón

Full Text Available RESUMEN Se presenta una metodología analítica retrospectiva, basada en el marco teórico de la eco-epidemiología, anclada en una escala espacial subnacional. Esta metodología, aplicada aquí a la caracterización de escenarios de transmisión de la leishmaniasis en la provincia argentina de Misiones —fronteriza con Brasil y Paraguay— permitió fundamentar recomendaciones de vigilancia y control apropiadas a dicha escala. Se realizó una búsqueda exhaustiva de la literatura sobre leishmaniasis en esa provincia y se determinaron tres escenarios de transmisión de leishmaniasis cutánea (LC y visceral (LV, correspondientes a tres períodos: 1920-1997, en el que se constató la transmisión de LC, dispersa en el tiempo y el espacio; 1998-2005, en el que hubo brotes focales de LC; y 2006-2014 en el que, además, se registraron brotes y se documentó la dispersión geográfica de la LV. Para caracterizar los escenarios de riesgo y los procesos antrópicos que los producen, los resultados se sintetizaron e integraron en el contexto socio-histórico y bio-ecológico de cada período analizado. Se fundamentan recomendaciones de vigilancia y control en el territorio estudiado, entre ellas, establecer una vigilancia activa para monitorear posibles tendencias al incremento de la circulación parasitaria y vectorial y, ante la aparición de un foco, realizar estudios para verificar la transmisión autóctona y la intensidad del evento. Además, se debe establecer la obligación legal de tomar medidas adicionales de control por los responsables de los proyectos que impliquen modificación ambiental, como la realización de estudios de evaluación del riesgo de transmisión, y acciones de mitigación del riesgo, detección temprana y tratamiento oportuno de los casos.

Fertility and pregnancy: an epidemiologic perspective

National Research Council Canada - National Science Library

Wilcox, Allen J

2010-01-01

.... Weaving together history, biology, obstetrics, pediatrics, demography, infectious diseases, molecular genetics, and evolutionary biology, Allen Wilcox brings a fresh coherence to the epidemiologic...

Strategic Engagement of Technical Surge Capacity for Intensified Polio Eradication Initiative in Nigeria, 2012–2015

Science.gov (United States)

Yehualashet, Yared G.; Mkanda, Pascal; Gasasira, Alex; Erbeto, Tesfaye; Onimisi, Anthony; Horton, Janet; Banda, Richard; Tegegn, Sisay G.; Ahmed, Haruna; Afolabi, Oluwole; Wadda, Alieu; Vaz, Rui G.; Nsubuga, Peter

2016-01-01

Background. Following the 65th World Health Assembly (WHA) resolution on intensification of the Global Poliomyelitis Eradication Initiative (GPEI), the Nigerian government, with support from the World Health Organization (WHO) and other partners, implemented a number of innovative strategies to curb the transmission of wild poliovirus (WPV) in the country. One of the innovations successfully implemented since mid 2012 is the WHO's engagement of surge capacity personnel. Methods. The WHO reorganized its functional structure, adopted a transparent recruitment and deployment process, provided focused technical and management training, and applied systematic accountability framework to successfully manage the surge capacity project in close collaboration with the national counterparts and partners. The deployment of the surge capacity personnel was guided by operational and technical requirement analysis. Results. Over 2200 personnel were engaged, of whom 92% were strategically deployed in 11 states classified as high risk on the basis of epidemiological risk analysis and compromised security. These additional personnel were directly engaged in efforts aimed at improving the performance of polio surveillance, vaccination campaigns, increased routine immunization outreach sessions, and strengthening partnership with key stakeholders at the operational level, including community-based organizations. Discussion. Programmatic interventions were sustained in states in which security was compromised and the risk of polio was high, partly owing to the presence of the surge capacity personnel, who are engaged from the local community. Since mid-2012, significant programmatic progress was registered in the areas of polio supplementary immunization activities, acute flaccid paralysis surveillance, and routine immunization with the support of the surge capacity personnel. As of 19 June 2015, the last case of WPV was reported on 24 July 2014. The surge infrastructure has

Epidemiology and natural history of vestibular schwannomas

DEFF Research Database (Denmark)

Stangerup, Sven-Eric; Caye-Thomasen, Per

2012-01-01

This article describes various epidemiologic trends for vestibular schwannomas over the last 35 years, including a brief note on terminology. Additionally, it provides information on the natural history of tumor growth and hearing level following the diagnosis of a vestibular schwannoma. A treatm......This article describes various epidemiologic trends for vestibular schwannomas over the last 35 years, including a brief note on terminology. Additionally, it provides information on the natural history of tumor growth and hearing level following the diagnosis of a vestibular schwannoma...

Carrying Capacity

DEFF Research Database (Denmark)

Schroll, Henning; Andersen, Jan; Kjærgård, Bente

2012-01-01

A spatial planning act was introduced inIndonesia 1992 and renewed in 2008. It emphasised the planning role of decentralised authorities. The spatial planning act covers both spatial and environmental issues. It defines the concept of carrying capacity and includes definitions of supportive....../cities. Four different sectors (water, food production, waste, and forests) were selected as core areas for decentralised spatial planning. Indicators for SCC and ACC were identified and assessed with regard to relevance and quantifiability. For each of the indicators selected, a legal threshold or guiding...... was introduced inIndonesia 1992 and renewed in 2008. It emphasised the planning role of decentralised authorities. The spatial planning act covers both spatial and environmental issues. It defines the concept of carrying capacity and includes definitions of supportive carrying capacity (SCC) and assimilative...

Epidemiology of whooping cough & typing of Bordetella pertussis.

Science.gov (United States)

Hegerle, Nicolas; Guiso, Nicole

2013-11-01

Bordetella pertussis is a Gram-negative human-restricted bacterium that evolved from the broad-range mammalian pathogen, Bordetella bronchiseptica. It causes whooping cough or pertussis in humans, which is the most prevalent vaccine-preventable disease worldwide. The introduction of the pertussis whole-cell vaccination for young children, followed by the introduction of the pertussis acellular vaccination (along with booster vaccination) for older age groups, has affected the bacterial population and epidemiology of the disease. B. pertussis is relatively monomorphic worldwide, but nevertheless, different countries are facing different epidemiological evolutions of the disease. Although it is tempting to link vaccine-driven phenotypic and genotypic evolution of the bacterium to epidemiology, many other factors should be considered and surveillance needs to continue, in addition to studies investigating the impact of current clinical isolates on vaccine efficacy.

Epidemiology in the Era of Health Informatics: Opportunities & Challenges

Directory of Open Access Journals (Sweden)

Rajesh Kumar

2016-03-01

Full Text Available Over the years, epidemiology has played a key role in improving our understanding about the determinants of health and disease. In the 19th century epidemiological observations led to the discovery of the modes of communication of cholera much before the discovery of the causative organism responsible for it. Similarly, in the 20th century, it led to the discovery of the risks of tobacco smoking, and the modes of transmission of AIDS. In the 21st century, advancement in the computation, visualization, communication, and mhealth technologies are likely to expand the landscape of epidemiology which has now acquired the status of a core discipline of health sciences.

1995 Annual epidemiologic surveillance report for Brookhaven National Laboratory

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-12-31

The US Department of Energy`s (DOE) conduct of epidemiologic surveillance provides an early warning system for health problems among workers. This program monitors illnesses and health conditions that result in an absence of five or more consecutive workdays, occupational injuries and illnesses, and disabilities and deaths among current workers. This report summarizes epidemiologic surveillance data collected from Brookhaven National Laboratory (BNL) from January 1, 1995 through December 31, 1995. The data were collected by a coordinator at BNL and submitted to the Epidemiologic Surveillance Data Center, located at Oak Ridge Institute for Science and Education, where quality control procedures and data analyses were carried out.

Air capacity for Sydney

OpenAIRE

Forsyth, Peter

2013-01-01

Like most large cities, Sydney has an airport problem. Demand is increasing faster than supply, and additional capacity will be needed if costly rationing, and delays, are to be avoided. However, compared to many cities, the problems facing Sydney are modest. At the moment, demand is only just exceeding capacity. There is a good chance that the available capacity will be rationed efficiently. Options for expanding capacity are being evaluated well. There may be problems in the future- poor op...

Meta-analysis in epidemiology | Yach | South African Medical Journal

African Journals Online (AJOL)

Meta-analysis is the structured and systematic qualitative and quantitative integration of the results of several independent studies (Le. the epidemiology of results). As in any epidemiological study, a meta-analysis needs to start with clearly stated aims and objectives. Attention needs to be paid to selection bias in selecting ...

WIN EPISCOPE 2.0: improved epidemiological software for veterinary medicine

NARCIS (Netherlands)

Thrusfield, M.; Ortega, C.; Blas, de I.; Noordhuizen, J.P.; Frankena, K.

2001-01-01

Recent changes in veterinary medicine have required quantitative epidemiological techniques for designing field surveys, identifying risk factors for multifactorial diseases, and assessing diagnostic tests. Several relevant techniques are brought together in the package of veterinary epidemiological

Capacity market design and renewable energy: Performance incentives, qualifying capacity, and demand curves

Energy Technology Data Exchange (ETDEWEB)

Botterud, Audun; Levin, Todd; Byers, Conleigh

2018-01-01

A review of capacity markets in the United States in the context of increasing levels of variable renewable energy finds substantial differences with respect to incentives for operational performance, methods to calculate qualifying capacity for variable renewable energy and energy storage, and demand curves for capacity. The review also reveals large differences in historical capacity market clearing prices. The authors conclude that electricity market design must continue to evolve to achieve cost-effective policies for resource adequacy.

Psychiatric epidemiology, or the story of a divided discipline.

Science.gov (United States)

Demazeux, Steeves

2014-08-01

This article traces the historical decisions, concepts and key professional collaborations that laid the foundations for the formation of American psychiatric epidemiology during the 20th century, up to the discipline's institutional consolidation, circa 1980, when the third edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-III) was published. Thomas Kuhn's 'disciplinary matrix' is mobilized as a framework that allows the institutional and intellectual construction of a discipline to be analysed as separate but intertwined components, without assuming that the two evolve in tandem. The identification of the strengths as well as the frailties and internal divisions of the discipline as it developed reveals a paradoxical situation: a time lag between psychiatric epidemiology's institutionalization and public recognition, on the one hand; and the weak coherence of its intellectual components, on the other hand. We briefly trace the origins of split among the discipline's aetiological models of mental disorders and suggest that the lack of coherence among them has prevented psychiatric epidemiology from achieving the status of a normal scientific discipline, in the Kuhnian sense. Without a more explicit attention to the intellectual rationale of the discipline, psychiatric epidemiology will continue to maintain a strong institutional dimension and weak intellectual matrix. © The Author 2014; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.

Capacity Expansion and Reliability Evaluation on the Networks Flows with Continuous Stochastic Functional Capacity

Directory of Open Access Journals (Sweden)

F. Hamzezadeh

2014-01-01

Full Text Available In many systems such as computer network, fuel distribution, and transportation system, it is necessary to change the capacity of some arcs in order to increase maximum flow value from source s to sink t, while the capacity change incurs minimum cost. In real-time networks, some factors cause loss of arc’s flow. For example, in some flow distribution systems, evaporation, erosion or sediment in pipes waste the flow. Here we define a real capacity, or the so-called functional capacity, which is the operational capacity of an arc. In other words, the functional capacity of an arc equals the possible maximum flow that may pass through the arc. Increasing the functional arcs capacities incurs some cost. There is a certain resource available to cover the costs. First, we construct a mathematical model to minimize the total cost of expanding the functional capacities to the required levels. Then, we consider the loss of flow on each arc as a stochastic variable and compute the system reliability.

Building a foundation for 'One Health': an education strategy for enhancing and sustaining national and regional capacity in endemic and emerging zoonotic disease management.

Science.gov (United States)

Vink, W D; McKenzie, Joanna S; Cogger, Naomi; Borman, Barry; Muellner, Petra

2013-01-01

The rapid global spread of diseases such as SARS, H5N1, and H1N1 influenza has emphasized the pressing need for trans-disciplinary collaboration and cross-border action, and has also exposed a serious deficit of capacity and coordination in dealing effectively with emerging disease threats. The need for capacity development is particularly acute in the developing world, which is the least well-equipped to respond adequately. Such capacity development can be achieved through education and the implementation of applied 'One Health' activities. This chapter describes the establishment of a 'One Health' capacity development program in South Asia, consisting of two phases. The first phase provides Masters level training for public health doctors and veterinarians, with a focus on epidemiology, and disease control. The second phase reinforces the postgraduate training by establishing a sustainable framework for the implementation of collaborative 'One Health' activities such as the development of multidisciplinary professional networks, implementation of applied zoonotic disease investigation projects, and support for continuing professional development. The objectives are to provide individual skills required to strengthen capacity; to develop an appreciation of the cross-cutting issues which affect human and animal health, set within an institutional context; and to facilitate the development of regional professional networks which will be instrumental in implementing 'One Health' activities.

Statistical significance of epidemiological data. Seminar: Evaluation of epidemiological studies

International Nuclear Information System (INIS)

Weber, K.H.

1993-01-01

In stochastic damages, the numbers of events, e.g. the persons who are affected by or have died of cancer, and thus the relative frequencies (incidence or mortality) are binomially distributed random variables. Their statistical fluctuations can be characterized by confidence intervals. For epidemiologic questions, especially for the analysis of stochastic damages in the low dose range, the following issues are interesting: - Is a sample (a group of persons) with a definite observed damage frequency part of the whole population? - Is an observed frequency difference between two groups of persons random or statistically significant? - Is an observed increase or decrease of the frequencies with increasing dose random or statistically significant and how large is the regression coefficient (= risk coefficient) in this case? These problems can be solved by sttistical tests. So-called distribution-free tests and tests which are not bound to the supposition of normal distribution are of particular interest, such as: - χ 2 -independence test (test in contingency tables); - Fisher-Yates-test; - trend test according to Cochran; - rank correlation test given by Spearman. These tests are explained in terms of selected epidemiologic data, e.g. of leukaemia clusters, of the cancer mortality of the Japanese A-bomb survivors especially in the low dose range as well as on the sample of the cancer mortality in the high background area in Yangjiang (China). (orig.) [de

What factors influence mitigative capacity?

International Nuclear Information System (INIS)

Winkler, Harald; Baumert, Kevin; Blanchard, Odile; Burch, Sarah; Robinson, John

2007-01-01

This article builds on Yohe's seminal piece on mitigative capacity, which elaborates 'determinants' of mitigative capacity, also reflected in the IPCC's third assessment report. We propose a revised definition, where mitigative capacity is a country's ability to reduce anthropogenic greenhouse gas emissions or enhance natural sinks. By 'ability' we mean skills, competencies, fitness, and proficiencies that a country has attained which can contribute to GHG emissions mitigation. A conceptual framework is proposed, linking mitigative capacity to a country's sustainable development path, and grouping the factors influencing mitigative capacity into three main sets: economic factors, institutional ones, and technology. Both quantitative and qualitative analysis of factors is presented, showing how these factors vary across countries. We suggest that it is the interplay between the three economic factors-income, abatement cost and opportunity cost-that shape mitigative capacity. We find that income is an important economic factor influencing mitigative capacity, while abatement cost is important in turning mitigative capacity into actual mitigation. Technology is a critical mitigative capacity, including the ability to absorb existing climate-friendly technologies or to develop innovative ones. Institutional factors that promote mitigative capacity include the effectiveness of government regulation, clear market rules, a skilled work force and public awareness. We briefly investigate such as high abatement cost or lack of political willingness that prevent mitigative capacity from being translated into mitigation

Concepts of social epidemiology in health services research

OpenAIRE

von dem Knesebeck, Olaf

2015-01-01

Background Social epidemiologists aim to identify social characteristics that affect the pattern of disease and health distribution in a society and to understand its mechanisms. Some important concepts of social epidemiology are: social inequalities, social relationships, social capital, and work stress. Discussion Concepts used in social epidemiology can make a useful contribution to health services research because the underlying social factors do not only influence health but are also rel...

CDMA systems capacity engineering

CERN Document Server

Kim, Kiseon

2004-01-01

This new hands-on resource tackles capacity planning and engineering issues that are crucial to optimizing wireless communication systems performance. Going beyond the system physical level and investigating CDMA system capacity at the service level, this volume is the single-source for engineering and analyzing systems capacity and resources.

Causal diagrams in systems epidemiology

Directory of Open Access Journals (Sweden)

Joffe Michael

2012-03-01

Full Text Available Abstract Methods of diagrammatic modelling have been greatly developed in the past two decades. Outside the context of infectious diseases, systematic use of diagrams in epidemiology has been mainly confined to the analysis of a single link: that between a disease outcome and its proximal determinant(s. Transmitted causes ("causes of causes" tend not to be systematically analysed. The infectious disease epidemiology modelling tradition models the human population in its environment, typically with the exposure-health relationship and the determinants of exposure being considered at individual and group/ecological levels, respectively. Some properties of the resulting systems are quite general, and are seen in unrelated contexts such as biochemical pathways. Confining analysis to a single link misses the opportunity to discover such properties. The structure of a causal diagram is derived from knowledge about how the world works, as well as from statistical evidence. A single diagram can be used to characterise a whole research area, not just a single analysis - although this depends on the degree of consistency of the causal relationships between different populations - and can therefore be used to integrate multiple datasets. Additional advantages of system-wide models include: the use of instrumental variables - now emerging as an important technique in epidemiology in the context of mendelian randomisation, but under-used in the exploitation of "natural experiments"; the explicit use of change models, which have advantages with respect to inferring causation; and in the detection and elucidation of feedback.

Causal diagrams in systems epidemiology.

Science.gov (United States)

Joffe, Michael; Gambhir, Manoj; Chadeau-Hyam, Marc; Vineis, Paolo

2012-03-19

Methods of diagrammatic modelling have been greatly developed in the past two decades. Outside the context of infectious diseases, systematic use of diagrams in epidemiology has been mainly confined to the analysis of a single link: that between a disease outcome and its proximal determinant(s). Transmitted causes ("causes of causes") tend not to be systematically analysed.The infectious disease epidemiology modelling tradition models the human population in its environment, typically with the exposure-health relationship and the determinants of exposure being considered at individual and group/ecological levels, respectively. Some properties of the resulting systems are quite general, and are seen in unrelated contexts such as biochemical pathways. Confining analysis to a single link misses the opportunity to discover such properties.The structure of a causal diagram is derived from knowledge about how the world works, as well as from statistical evidence. A single diagram can be used to characterise a whole research area, not just a single analysis - although this depends on the degree of consistency of the causal relationships between different populations - and can therefore be used to integrate multiple datasets.Additional advantages of system-wide models include: the use of instrumental variables - now emerging as an important technique in epidemiology in the context of mendelian randomisation, but under-used in the exploitation of "natural experiments"; the explicit use of change models, which have advantages with respect to inferring causation; and in the detection and elucidation of feedback.

[Epidemiology of tumors in the construction industry].

Science.gov (United States)

Assennato, G; Cuccaro, F

2012-01-01

Many epidemiological studies, mostly with a case-control design, show an increased risk of cancer, in particular lung cancer, in construction workers. Asbestos is the occupational carcinogen considered for a long time the most important in this sector, but now it covers a residual role, at least in Italy. In this review the most recent studies are considered and the presence of other carcinogens, as crystalline silica, man-made mineral fibers, diesel exhausts, metals, solvents, UV rays, must be considered in risk evaluation also, possibly, for health and epidemiologic surveillance.

Worldwide Report, Epidemiology

Science.gov (United States)

1985-11-22

caused by ingesting eggs of the pork tapeworm, Taenia solium . It has been described as the most com- mon parasitic disease of the central nervous...rather difficult to detect in stool specimens and at this stage it is impossible to distinguish between T. solium and T. saginata eggs either by...Knowledge and Perspectives, pp. 25-38. Academic Press, New York. 12. Pawlowskz S. (1982). Epidemiology and prevention of Taenia saginata infec- tion. In

1995 annual epidemiologic surveillance report for Fernald Environmental Management Project

International Nuclear Information System (INIS)

1995-01-01

The US Department of Energy's (DOE) commitment to assuring the health and safety of its workers includes the conduct of epidemiologic surveillance activities that provide an early warning system for health problems among workers. During the past several years, a number of DOE sites have participated in the Epidemiologic Surveillance Program. This program monitors illnesses and health conditions that result in an absence of five or more consecutive workdays, occupational injuries and illnesses, and disabilities and deaths among current workers. This report provides a summary of epidemiologic surveillance data collected from the Fernald Environmental Management Project (FEMP) from January 1, 1995 through December 31, 1995. The data were collected by a coordinator at FEMP and submitted to the Epidemiologic Surveillance Data Center, located at Oak Ridge Institute for Science and Education, where quality control procedures and data analyses were carried out

1995 annual epidemiologic surveillance report for Fernald Environmental Management Project

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-12-31

The US Department of Energy's (DOE) commitment to assuring the health and safety of its workers includes the conduct of epidemiologic surveillance activities that provide an early warning system for health problems among workers. During the past several years, a number of DOE sites have participated in the Epidemiologic Surveillance Program. This program monitors illnesses and health conditions that result in an absence of five or more consecutive workdays, occupational injuries and illnesses, and disabilities and deaths among current workers. This report provides a summary of epidemiologic surveillance data collected from the Fernald Environmental Management Project (FEMP) from January 1, 1995 through December 31, 1995. The data were collected by a coordinator at FEMP and submitted to the Epidemiologic Surveillance Data Center, located at Oak Ridge Institute for Science and Education, where quality control procedures and data analyses were carried out.

Bacterial meningitis: epidemiology, herd protection, clinical characteristics, and risk assessment

NARCIS (Netherlands)

Bijlsma, M.W.

2016-01-01

This thesis studied the epidemiology of community-acquired bacterial meningitis after the nationwide implementation of paediatric conjugate vaccines, as well as the long-term epidemiology of invasive meningococcal disease and neonatal group B streptococcal disease in the Netherlands. Furthermore,

Ionizing radiation biomarkers for potential use in epidemiological studies

International Nuclear Information System (INIS)

Pernot, Eileen; Cardis, Elisabeth; Hall, Janet; Baatout, Sarah; El Saghire, Houssein; Mohammed Abderrafi Benotmane; Roel Quintens; Blanchardon, Eric; Bouffler, Simon; Gomolka, Maria; Guertler, Anne; Kreuzer, Michaela; Harms-Ringdahl, Mats; Jeggo, Penny; Laurier, Dominique; Lindholm, Carita; Mkacher, Radhia; Sabatier, Laure; Tapio, Soile; De Vathaire, Florent

2012-01-01

Ionizing radiation is a known human carcinogen that can induce a variety of biological effects depending on the physical nature, duration, doses and dose-rates of exposure. However, the magnitude of health risks at low doses and dose-rates (below 100 mSv and/or 0.1 mSv min -1 ) remains controversial due to a lack of direct human evidence. It is anticipated that significant insights will emerge from the integration of epidemiological and biological research, made possible by molecular epidemiology studies incorporating biomarkers and bioassays. A number of these have been used to investigate exposure, effects and susceptibility to ionizing radiation, albeit often at higher doses and dose rates, with each reflecting time-limited cellular or physiological alterations. This review summarises the multidisciplinary work undertaken in the framework of the European project DoReMi (Low Dose Research towards Multidisciplinary Integration) to identify the most appropriate biomarkers for use in population studies. In addition to logistical and ethical considerations for conducting large-scale epidemiological studies, we discuss the relevance of their use for assessing the effects of low dose ionizing radiation exposure at the cellular and physiological level. We also propose a temporal classification of biomarkers that may be relevant for molecular epidemiology studies which need to take into account the time elapsed since exposure. Finally, the integration of biology with epidemiology requires careful planning and enhanced discussions between the epidemiology, biology and dosimetry communities in order to determine the most important questions to be addressed in light of pragmatic considerations including the appropriate population to be investigated (occupationally, environmentally or medically exposed), and study design. The consideration of the logistics of biological sample collection, processing and storing and the choice of biomarker or bioassay, as well as awareness of

Epidemiology of Chronic Pain in Denmark and Sweden

Directory of Open Access Journals (Sweden)

Julie Harker

2012-01-01

Full Text Available Introduction. Estimates on the epidemiology of chronic pain vary widely throughout Europe. It is unclear whether this variation reflects true differences between populations or methodological factors. Information on the epidemiology of chronic pain can support decision makers in allocating adequate health care resources. Methods. In order to obtain epidemiological data on chronic pain in Denmark and Sweden, we conducted a literature review of epidemiological data primarily on chronic noncancer pain, prioritising studies of highest quality, recency, and validity by conducting a systematic search for relevant studies. Following quality assessment, data were summarised and assigned to the research questions. Results. The prevalence of moderate to severe noncancer pain was estimated at 16% in Denmark and 18% in Sweden. Chronic pain impacts negatively on perceived health status, quality of life and is associated with increased cost. Despite using pain medications, a large proportion of chronic pain sufferers have inadequate pain control. There was a lack of high-quality and low-bias studies with clear inclusion criteria. Conclusions. In both Denmark and Sweden, chronic pain is a common health problem which is potentially undertreated and warrants attention of health care workers, policy makers and researchers. Future research should utilise clear reporting guidelines to assist decision and policy makers, in this important area.

Brain Tumor Epidemiology Consortium (BTEC)

Science.gov (United States)

The Brain Tumor Epidemiology Consortium is an open scientific forum organized to foster the development of multi-center, international and inter-disciplinary collaborations that will lead to a better understanding of the etiology, outcomes, and prevention of brain tumors.

en epidemiología

Directory of Open Access Journals (Sweden)

Ana V. Diez Roux

2008-01-01

Full Text Available La epidemiología sociocultural se caracteriza por la integración de procesos sociales, culturales, económicos y políticos con procesos biológicos en el estudio de los determinantes de la salud. Por definición, esto implica la consideración de determinantes especificados a múltiples niveles, desde los genes hasta las características de la sociedad en su totalidad. En este artículo se analizan diversos problemas metodológicos que surgen en epidemiología (y en las ciencias sociales en general por la presencia de múltiples niveles de organización que pueden ser relevantes para entender las causas de la salud y la enfermedad. Se subraya la necesidad de investigar conjuntamente (o de integrar determinantes de la salud definidos a distintos niveles. El artículo concluye con un examen de las implicaciones de la presencia de múltiples niveles para el estudio de los determinantes sociales o culturales de la salud.

Epidemiology: second-rate science?

Science.gov (United States)

Parascandola, M

1998-01-01

In recent years epidemiology has come under increasing criticism in regulatory and public arenas for being "unscientific." The tobacco industry has taken advantage of this, insisting for decades that evidence linking cigarettes and lung cancer falls short of proof. Moreover, many epidemiologists remain unduly skeptical and self-conscious about the status of their own causal claims. This situation persists in part because of a widespread belief that only the laboratory can provide evidence sufficient for scientific proof. Adherents of this view erroneously believe that there is no element of uncertainty or inductive inference in the "direct observation" of the laboratory researcher and that epidemiology provides mere "circumstantial" evidence. The historical roots of this attitude can be traced to philosopher John Stuart Mill and physiologist Claude Bernard and their influence on modern experimental thinking. The author uses the debate over cigarettes and lung cancer to examine ideas of proof in medical science and public health, concluding that inductive inference from a limited sample to a larger population is an element in all empirical science.

OPEC future capacity expansions

International Nuclear Information System (INIS)

Sandrea, I.

2005-01-01

This conference presentation examined OPEC future capacity expansions including highlights from 2000-2004 from the supply perspective and actions by OPEC; OPEC spare capacity in 2005/2006; medium-term capacity expansion and investments; long-term scenarios, challenges and opportunities; and upstream policies in member countries. Highlights from the supply perspective included worst than expected non-OPEC supply response; non-OPEC supply affected by a number of accidents and strikes; geopolitical tensions; and higher than expected demand for OPEC crude. OPEC's actions included closer relationship with other producers and consumers; capacity expansions in 2004 and 2005/2006; and OPEC kept the market well supplied with crude in 2004. The presentation also provided data using graphical charts on OPEC net capacity additions until 2005/2006; OPEC production versus spare capacity from 2003 to 2005; OPEC production and capacity to 2010; and change in required OPEC production from 2005-2020. Medium term expansion to 2010 includes over 60 projects. Medium-term risks such as project execution, financing, costs, demand, reserves, depletion, integration of Iraq, and geopolitical tensions were also discussed. The presentation concluded that in the long term, large uncertainties remain; the peak of world supply is not imminent; and continued and enhanced cooperation is essential to market stability. tabs., figs

“Epidemiological Criminology”: Coming Full Circle

Science.gov (United States)

Lanier, Mark M.

2009-01-01

Members of the public health and criminal justice disciplines often work with marginalized populations: people at high risk of drug use, health problems, incarceration, and other difficulties. As these fields increasingly overlap, distinctions between them are blurred, as numerous research reports and funding trends document. However, explicit theoretical and methodological linkages between the 2 disciplines remain rare. A new paradigm that links methods and statistical models of public health with those of their criminal justice counterparts is needed, as are increased linkages between epidemiological analogies, theories, and models and the corresponding tools of criminology. We outline disciplinary commonalities and distinctions, present policy examples that integrate similarities, and propose “epidemiological criminology” as a bridging framework. PMID:19150901

Considerações acerca dos fundamentos teóricos da explicação em epidemiología Considerations concerning the theoretical foundations of explanation in epidemiology

Directory of Open Access Journals (Sweden)

Luiz Jacintho da Silva

1985-08-01

Full Text Available São analisadas as condições históricas do surgimento da epidemiologia como disciplina científica, em meados do século passado. É revista a evolução das bases teóricas do processo explicativo em epidemiologia até o momento atual. Especial atenção é dada ao papel da lógica positivista de Stuart Mill como base teórica da Epidemiologia até recentemente. São discutidas as alternativas teóricas correntes e proposta maior abertura da epidemiologia a diferentes correntes filosóficas como o caminho para o estabelecimento da epidemiologia como uma ciência madura.The historical conditions surrounding the emergence, by the mid-19th century, of epidemiology as a scientific discipline, were analysed. Special consideration is given to the influence of the political milieu of Victorian England in the definition of the theoretical basis of epidemiology. The English Sanitary Movement is seen as a response of the emerging bourgeoise to problems created by industrialization and urbanization. As a consequence, epidemiology was strongly influenced by Stuart Mill's system of logic. During the latter part of the 19th century, bacteriology brought important transformations to epidemiology. However, its theoretical foundations suffered almost no change. Possibly the new challenges created by -the expanding colonial empires were the driving force in the evolution of epidemiology. As a science, it could not escape from the influence of social and political forces, It has only been recently, mainly in Latin America, that a search for alternatives to the dominating theoretical structure of epidemiology has taken place. The historical-materialist approach has given way to what is sometimes refered to as "social epidemiology". Epidemiology should be regarded as a science in which different theoretical approaches may coexist, as in history, sociology or physics.

Accidents, disasters and crisis: contribution of epidemiology in the nuclear field

International Nuclear Information System (INIS)

Verger, P.; Bard, D.; Hubert, P.

1995-01-01

The experience of the Chernobyl accident has shown the necessity of being prepared for epidemiological assessment of the health consequences of a nuclear or a radiological accident. We discuss the contribution of epidemiology in such situations, in addition to the existing tools designed to assess or manage radiological risks. From a decisional point of view, three issues are distinguished: the protection of the different population groups against ionizing radiations, the achievement of health care and the communication with the public and media. We discuss the input of epidemiological tools in both perspectives. Epidemiology may also contribute to the analysis of health events that may be observed after an accident, i.e. to assess whether these events are not statistical artifacts, whether they are an effect of the exposure to ionizing radiations or a non specific consequence of any accident. Finally, epidemiological studies should be carried out to improve our knowledge on ionizing radiations effects with a special consideration given to the dose-effect relationships. Examples of past nuclear accidents are used to discuss these issues. The last part of this paper is focused on different research issues that should be developed for preparing epidemiological plans for nuclear accidents. (Author). 48 refs., 1 fig., 3 tabs

TFOS DEWS II Epidemiology Report

NARCIS (Netherlands)

Stapleton, Fiona; Alves, Monica; Bunya, Vatinee Y.; Jalbert, Isabelle; Lekhanont, Kaevalin; Malet, Florence; Na, Kyung-Sun; Schaumberg, Debra; Uchino, Miki; Vehof, Jelle; Viso, Eloy; Vitale, Susan; Jones, Lyndon

The subcommittee reviewed the prevalence, incidence, risk factors, natural history, morbidity and questionnaires reported in epidemiological studies of dry eye disease (DED). A meta-analysis of published prevalence data estimated the impact of age and sex. Global mapping of prevalence was

Epidemiology in conflict – A call to arms

Directory of Open Access Journals (Sweden)

Tam Clarence C

2004-10-01

Full Text Available Abstract In this first special theme issue, Emerging Themes in Epidemiology publishes a collection of articles on the theme of Epidemiology in conflict. Violent conflict is an issue of great sensitivity within public health, but more structured research and reasoned discussion will allow us to better mitigate the public health impacts of war, and place the public health community in a more informed position in discussions about possible interventions in future conflicts.

Recognizing excellence in maternal and child health (MCH) epidemiology: the 2012 Co-hosted 18th MCH Epidemiology Conference and 22nd CityMatCH Urban MCH Leadership Conference, the 25th anniversary of the MCH Epidemiology Program, and the National MCH Epidemiology Awards.

Science.gov (United States)

Kroelinger, Charlan D; Jones, Jessica; Barfield, Wanda D; Kogan, Michael D

2014-09-01

In December 2012, multiple leading agencies in the field of Maternal and Child Health (MCH) partnered to co-host a national MCH Epidemiology Conference. The Conference offered opportunities for peer exchange; presentation of new scientific methodologies, programs, and policies; dialogue on changes in the MCH field; and discussion of emerging MCH issues relevant to the work of MCH professionals. During the Conference, the MCH Epidemiology Program celebrated 25 years of success and partnership, and 16 MCH agencies presented six deserving health researchers and leaders with national awards in the areas of advancing knowledge, effective practice, outstanding leadership, excellence in teaching and mentoring, and young professional achievement. In September 2014, building on knowledge gained and changes in the field of MCH, leading agencies including the Centers for Disease Control and Prevention, the Health Resources and Services Administration, CityMatCH, and the Association of MCH Programs plan to replicate the achievements of 2012 through the implementation of a fully integrated national conference: the CityMatCH Leadership and MCH Epidemiology Conference.

Dementia, Decision Making, and Capacity.

Science.gov (United States)

Darby, R Ryan; Dickerson, Bradford C

After participating in this activity, learners should be better able to:• Assess the neuropsychological literature on decision making and the medical and legal assessment of capacity in patients with dementia• Identify the limitations of integrating findings from decision-making research into capacity assessments for patients with dementia ABSTRACT: Medical and legal professionals face the challenge of assessing capacity and competency to make medical, legal, and financial decisions in dementia patients with impaired decision making. While such assessments have classically focused on the capacity for complex reasoning and executive functions, research in decision making has revealed that motivational and metacognitive processes are also important. We first briefly review the neuropsychological literature on decision making and on the medical and legal assessment of capacity. Next, we discuss the limitations of integrating findings from decision-making research into capacity assessments, including the group-to-individual inference problem, the unclear role of neuroimaging in capacity assessments, and the lack of capacity measures that integrate important facets of decision making. Finally, we present several case examples where we attempt to demonstrate the potential benefits and important limitations of using decision-making research to aid in capacity determinations.

Epidemiology of Uterine Myomas: A Review

Directory of Open Access Journals (Sweden)

Radmila Sparic

2016-12-01

Full Text Available Myomas are the most common benign tumors of the genital organs in women of childbearing age, causing significant morbidity and impairing their quality of life. In our investigation, we have reviewed the epidemiological data related to the development of myomas in order to homogenize the current data. Therefore, a MEDLINE and PubMed search, for the years 1990-2013, was conducted using a combination of keywords, such as "myoma," "leiomyoma," "fibroids," "myomectomy," "lifestyle," "cigarette," "alcohol," "vitamins," "diet," and "hysterectomy". Randomized controlled studies were selected based upon the authors’ estimation. Peer-reviewed articles examining myomas were sorted by their relevance and included in this research. Additional articles were also identified from the references of the retrieved papers and included according to authors’ estimation. Many epidemiologic factors are linked to the development of myomas; however, many are not yet fully understood. These factors include age, race, heritage, reproductive factors, sex hormones, obesity, lifestyle (diet, caffeine and alcohol consumption, smoking, physical activity and stress, environmental and other influences, such as hypertension and infection. Some of the epidemiological data is conflicting. Thus, more research is needed to understand all the risk factors that contribute to myoma formation and how they exactly influence their onset and growth.

[Biology and culture: a dimension of collaboration between anthropology and epidemiology].

Science.gov (United States)

Song, Leiming; Wang, Ning

2016-01-01

Biology is the important basis of epidemiological study. Based on biology, psychology, social and cultural factors can influence human's health and disease incidence. The medical mode has changed from "biomedical mode" to "bio-psycho-social medical model" , but culture factor was neglected somewhat during this process, so paying attention to culture factor in anthropologic study and using it as biologic basis in epidemiologic study might be a dimension of collaboration between of anthropology and epidemiology.

Savannah River Site 1996 epidemiologic surveillance report

International Nuclear Information System (INIS)

2000-01-01

This report provides a summary of epidemiologic surveillance data collected from Savannah River Site from January 1, 1996 through December 31, 1996. The data were collected by a coordinator at Savannah River Site and submitted to the Epidemiologic Surveillance Data Center located at Oak Ridge Institute for Science and Education, where quality control procedures and preliminary data analyses were carried out. The analyses were interpreted and the final report prepared by the DOE Office of Epidemiologic Studies. The information in this report provides highlights of the data analyses conducted on the 1996 data collected from Savannah River Site. The main sections of the report include: work force characteristics; absences due to injury or illness lasting 5 or more consecutive workdays; workplace illnesses, injuries, and deaths that were reportable to the Occupational Safety and Health Administration (''OSHA-recordable'' events); and disabilities and deaths among current workers. The 1996 report includes a new section on time trends that provides comparative information on the health of the work force from 1994 through 1996

Savannah River Site 1997 epidemiologic surveillance report

International Nuclear Information System (INIS)

2000-01-01

This report provides a summary of epidemiologic surveillance data collected from Savannah River Site from January 1, 1997 through December 31, 1997. The data were collected by a coordinator at Savannah River Site and submitted to the Epidemiologic Surveillance Data Center located at Oak Ridge Institute for Science and Education, where quality control procedures and preliminary data analyses were carried out. The analyses were interpreted and the final report prepared by the DOE Office of Epidemiologic Studies. The information in this report provides highlights of the data analyses conducted on the 1997 data collected from Savannah River Site. The main sections of the report include: work force characteristics; absences due to injury or illness lasting 5 or more consecutive workdays; workplace illnesses, injuries, and deaths that were reportable to the Occupational Safety and Health Administration (''OSHA-recordable'' events); and disabilities and deaths among current workers. The 199 7 report includes a section on time trends that provides comparative information on the health of the work force from 1994 through 1997

Experimental infection and transmission of Leishmania by Lutzomyia cruzi (Diptera: Psychodidae: Aspects of the ecology of parasite-vector interactions.

Directory of Open Access Journals (Sweden)

Everton Falcão de Oliveira

2017-02-01

Full Text Available Several parameters should be addressed before incriminating a vector for Leishmania transmission. Those may include its ability to become infected by the same Leishmania species found in humans, the degree of attractiveness for reservoirs and humans and capacity to sustain parasite infection under laboratory conditions. This study evaluated the vectorial capacity of Lutzomyia cruzi for Leishmania infantum and gathered information on its ability to harbor L. amazonensis. Laboratory-reared Lu. cruzi were infected experimentally by feeding them on dogs infected naturally with L. infantum and hamsters infected with L. amazonensis. Sand fly attractiveness to dogs and humans was determined using wild caught insects. The expected daily survival of infected Lu. cruzi, the duration of the gonotrophic cycle, and the extrinsic incubation period were also investigated for both parasites. Vector competence was investigated for both Leishmania species. The mean proportion of female sand flies that fed on hosts was 0.40. For L. infantum and L. amazonensis, Lu. cruzi had experimental infection rates of 10.55% and 41.56%, respectively. The extrinsic incubation period was 3 days for both Leishmania species, regardless of the host. Survival expectancy of females infected with L. infantum and L. amazonensis after completing the gonotrophic cycle was 1.32 and 0.43, respectively. There was no association between L. infantum infection and sand fly longevity, but L. amazonensis-infected flies had significantly greater survival probabilities. Furthermore, egg-laying was significantly detrimental to survival. Lu. cruzi was found to be highly attracted to both dogs and humans. After a bloodmeal on experimentally infected hosts, both parasites were able to survive and develop late-stage infections in Lu. cruzi. However, transmission was demonstrated only for L. amazonensis-infected sand flies. In conclusion, Lu. cruzi fulfilled several of the requirements of vectorial

Experimental infection and transmission of Leishmania by Lutzomyia cruzi (Diptera: Psychodidae): Aspects of the ecology of parasite-vector interactions.

Science.gov (United States)

Falcão de Oliveira, Everton; Oshiro, Elisa Teruya; Fernandes, Wagner de Souza; Murat, Paula Guerra; Medeiros, Márcio José de; Souza, Alda Izabel; Oliveira, Alessandra Gutierrez de; Galati, Eunice Aparecida Bianchi

2017-02-01

Several parameters should be addressed before incriminating a vector for Leishmania transmission. Those may include its ability to become infected by the same Leishmania species found in humans, the degree of attractiveness for reservoirs and humans and capacity to sustain parasite infection under laboratory conditions. This study evaluated the vectorial capacity of Lutzomyia cruzi for Leishmania infantum and gathered information on its ability to harbor L. amazonensis. Laboratory-reared Lu. cruzi were infected experimentally by feeding them on dogs infected naturally with L. infantum and hamsters infected with L. amazonensis. Sand fly attractiveness to dogs and humans was determined using wild caught insects. The expected daily survival of infected Lu. cruzi, the duration of the gonotrophic cycle, and the extrinsic incubation period were also investigated for both parasites. Vector competence was investigated for both Leishmania species. The mean proportion of female sand flies that fed on hosts was 0.40. For L. infantum and L. amazonensis, Lu. cruzi had experimental infection rates of 10.55% and 41.56%, respectively. The extrinsic incubation period was 3 days for both Leishmania species, regardless of the host. Survival expectancy of females infected with L. infantum and L. amazonensis after completing the gonotrophic cycle was 1.32 and 0.43, respectively. There was no association between L. infantum infection and sand fly longevity, but L. amazonensis-infected flies had significantly greater survival probabilities. Furthermore, egg-laying was significantly detrimental to survival. Lu. cruzi was found to be highly attracted to both dogs and humans. After a bloodmeal on experimentally infected hosts, both parasites were able to survive and develop late-stage infections in Lu. cruzi. However, transmission was demonstrated only for L. amazonensis-infected sand flies. In conclusion, Lu. cruzi fulfilled several of the requirements of vectorial capacity for L. infantum

PAYMENT CAPACITY SENSITIVITY FACTORS

Directory of Open Access Journals (Sweden)

Daniel BRÎNDESCU – OLARIU

2014-11-01

The results of the study facilitate the determination and classification of the main sensitivity factors for the payment capacity at sample level, the establishment of general benchmarks for the payment capacity (as no such benchmarks currently exist in the Romanian literature and the identification of the mechanisms through which the variation of different factors impacts the payment capacity.

Validity of various epidemiological approaches to assessing radon health risk

International Nuclear Information System (INIS)

Conrath, S.M.

1990-01-01

In this paper various epidemiologic study designs are defined and evaluated for their utility in assessing radon health risk. The strengths and limitations of these approaches are addressed. Common pitfalls and errors of epidemiologic method are delineated with examples of causes and remedies

A two-step recognition of signal sequences determines the translocation efficiency of proteins.

Science.gov (United States)

Belin, D; Bost, S; Vassalli, J D; Strub, K

1996-02-01

The cytosolic and secreted, N-glycosylated, forms of plasminogen activator inhibitor-2 (PAI-2) are generated by facultative translocation. To study the molecular events that result in the bi-topological distribution of proteins, we determined in vitro the capacities of several signal sequences to bind the signal recognition particle (SRP) during targeting, and to promote vectorial transport of murine PAI-2 (mPAI-2). Interestingly, the six signal sequences we compared (mPAI-2 and three mutated derivatives thereof, ovalbumin and preprolactin) were found to have the differential activities in the two events. For example, the mPAI-2 signal sequence first binds SRP with moderate efficiency and secondly promotes the vectorial transport of only a fraction of the SRP-bound nascent chains. Our results provide evidence that the translocation efficiency of proteins can be controlled by the recognition of their signal sequences at two steps: during SRP-mediated targeting and during formation of a committed translocation complex. This second recognition may occur at several time points during the insertion/translocation step. In conclusion, signal sequences have a more complex structure than previously anticipated, allowing for multiple and independent interactions with the translocation machinery.

Fasciola hepatica in snails collected from water-dropwort fields using PCR.

Science.gov (United States)

Kim, Hwang-Yong; Choi, In-Wook; Kim, Yeon-Rok; Quan, Juan-Hua; Ismail, Hassan Ahmed Hassan Ahmed; Cha, Guang-Ho; Hong, Sung-Jong; Lee, Young-Ha

2014-12-01

Fasciola hepatica is a trematode that causes zoonosis mainly in cattle and sheep and occasionally in humans. Fascioliasis has been reported in Korea; however, determining F. hepatica infection in snails has not been done recently. Thus, using PCR, we evaluated the prevalence of F. hepatica infection in snails at 4 large water-dropwort fields. Among 349 examined snails, F. hepatica-specific internal transcribed space 1 (ITS-1) and/or ITS-2 markers were detected in 12 snails and confirmed using sequence analysis. Morphologically, 213 of 349 collected snails were dextral shelled, which is the same aperture as the lymnaeid snail, the vectorial host for F. hepatica. Among the 12 F. hepatica-infected snails, 6 were known first intermediate hosts in Korea (Lymnaea viridis and L. ollula) and the remaining 6 (Lymnaea sp.) were potentially a new first intermediate host in Korea. It has been shown that the overall prevalence of the snails contaminated with F. hepatica in water-dropwort fields was 3.4%; however, the prevalence varied among the fields. This is the first study to estimate the prevalence of F. hepatica infection using the vectorial capacity of the snails in Korea.

Epidemiology: past, present and future.

Science.gov (United States)

Kesteloot, H

2004-01-01

Epidemiology in the past was concerned essentially by the study of infectious diseases which were the cause of huge mortalities especially since urbanisation was initiated. Epidemics of pest, typhus, cholera, influenza a.o. were common. The epidemics were halted by better hygiene, vaccination and antibiotics. Since the second world war epidemiology was dominated by an "epidemic" of new chronic diseases, especially heart disease and cancer. This was due to an increase in life span and to an increase in smoking habits and in the intake of saturated fat and a too small intake of fruit and vegetables combined with a too high intake of salt (NaCl). Gradually epidemiology evolved as the study of the causes, the distribution, the risk factors and the prevention of chronic diseases, but also including accidents, suicide, depression a.o., diseases with a mass occurrence at the population level. The importance of nutrition as a determinant of health gradually became recognized, but remains undervalued by the medical profession. Mortality at the population level follows some simple mathematical laws and can be represented accurately (r2>0.99) between the ages of 35 and 84 year by either Gompertz equations (ln mortality versus age) or by a polynomial equation (ln mortality versus age, age2). This is valid for all populations and both sexes and remains valid at times of great and rapid changes in mortality. This shows that measures for prevention should be directed towards the total population. The future of epidemiology should be directed towards the slowing of the ageing process at the population level by a healthy life style consisting of: not smoking, avoiding obesity, a fair amount of physical activity and a healthy nutrition i.e little salt, little saturated fat, an adequate amount of omega-3 fatty acids and a large amount of fruit and vegetables, with an occasional glass of red wine. This contains the secret of a long and healthy life. Conceptually it will be important

[Epidemiology of type 1 diabetes mellitus in children in Spain].

Science.gov (United States)

Conde Barreiro, S; Rodríguez Rigual, M; Bueno Lozano, G; López Siguero, J P; González Pelegrín, B; Rodrigo Val, M P; Compés Dea, M L

2014-09-01

Epidemiological studies in many regions and countries have contributed to determining the epidemiology of type 1 diabetes (T1DM) in children less than 15 years old. Studies in many regions of Spain have been published, but the national incidence is not really known. A review was made of the publications on the epidemiology of T1DM in Spain, selecting the references on patients less than 15 years old. Many epidemiological studies on T1DM in almost all regions in Spain have been published. The methodology of these studies is heterogeneous, with variations in geographical definition, duration, period of study, limit of age, and data collection. The incidence rates are variable, from 11.5 cases per 100,000/year in Asturias to 27.6 in Castilla-La Mancha. Some studies report the percentage of diabetic ketoacidosis at the time of diagnosis, which is usually in the range of 25-40%. Although there have been various epidemiological studies on T1DM in almost all regions in Spain, the methodology is heterogeneous. The mean incidence of T1DM in children less than 15 years old in Spain, stimated from the selected studies is 17,69 cases per 100,000/year. T1DM registers need to be created and updated, using standardized methodology, to get more reliable data of the epidemiology of T1DM in Spain in the near future. Copyright © 2013 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.

Panel 1 : Epidemiology and Diagnosis

NARCIS (Netherlands)

Homøe, Preben; Kværner, Kari; Casey, Janet R; Damoiseaux, Roger A M J; van Dongen, Thijs M A; Gunasekera, Hasantha; Jensen, Ramon G; Kvestad, Ellen; Morris, Peter S; Weinreich, Heather M

Objective To create a literature review between 2011 and June 1, 2015, on advances in otitis media (OM) epidemiology and diagnosis (including relevant audiology studies). Data Sources Electronic search engines (PubMed, EMBASE, and Cochrane Library) with a predefined search strategy. Review Methods

Population Neuroscience: Dementia Epidemiology Serving Precision Medicine and Population Health.

Science.gov (United States)

Ganguli, Mary; Albanese, Emiliano; Seshadri, Sudha; Bennett, David A; Lyketsos, Constantine; Kukull, Walter A; Skoog, Ingmar; Hendrie, Hugh C

2018-01-01

Over recent decades, epidemiology has made significant contributions to our understanding of dementia, translating scientific discoveries into population health. Here, we propose reframing dementia epidemiology as "population neuroscience," blending techniques and models from contemporary neuroscience with those of epidemiology and biostatistics. On the basis of emerging evidence and newer paradigms and methods, population neuroscience will minimize the bias typical of traditional clinical research, identify the relatively homogenous subgroups that comprise the general population, and investigate broader and denser phenotypes of dementia and cognitive impairment. Long-term follow-up of sufficiently large study cohorts will allow the identification of cohort effects and critical windows of exposure. Molecular epidemiology and omics will allow us to unravel the key distinctions within and among subgroups and better understand individuals' risk profiles. Interventional epidemiology will allow us to identify the different subgroups that respond to different treatment/prevention strategies. These strategies will inform precision medicine. In addition, insights into interactions between disease biology, personal and environmental factors, and social determinants of health will allow us to measure and track disease in communities and improve population health. By placing neuroscience within a real-world context, population neuroscience can fulfill its potential to serve both precision medicine and population health.

Using mobile technology to conduct epidemiological investigations

Directory of Open Access Journals (Sweden)

Onicio Batista Leal Neto

2015-02-01

Full Text Available INTRODUCTION : The aim of this study was to report the experience of an epidemiological field survey for which data were collected and analyzed using tablets. METHODS : The devices used Epi Info 7 (Android version, which has been modeled a database with variables of the traditional form. RESULTS : Twenty-one households were randomly selected in the study area; 75 residents were registered and completed household interviews with socioeconomic and environmental risk variables. CONCLUSIONS : This new technology is a valuable tool for collecting and analyzing data from the field, with advantageous benefits to epidemiological surveys.

Recruitment and Participation of Recreational Runners in a Large Epidemiological and Genetic Research Study: Retrospective Data Analysis.

Science.gov (United States)

Manzanero, Silvia; Kozlovskaia, Maria; Vlahovich, Nicole; Hughes, David C

2018-05-23

With the increasing capacity for remote collection of both data and samples for medical research, a thorough assessment is needed to determine the association of population characteristics and recruitment methodologies with response rates. The aim of this research was to assess population representativeness in a two-stage study of health and injury in recreational runners, which consisted of an epidemiological arm and genetic analysis. The cost and success of various classical and internet-based methods were analyzed, and demographic representativeness was assessed for recruitment to the epidemiological survey, reported willingness to participate in the genetic arm of the study, actual participation, sample return, and approval for biobank storage. A total of 4965 valid responses were received, of which 1664 were deemed eligible for genetic analysis. Younger age showed a negative association with initial recruitment rate, expressed willingness to participate in genetic analysis, and actual participation. Additionally, female sex was associated with higher initial recruitment rates, and ethnic origin impacted willingness to participate in the genetic analysis (all P<.001). The sharp decline in retention through the different stages of the study in young respondents suggests the necessity to develop specific recruitment and retention strategies when investigating a young, physically active population. ©Silvia Manzanero, Maria Kozlovskaia, Nicole Vlahovich, David C Hughes. Originally published in JMIR Research Protocols (http://www.researchprotocols.org), 23.05.2018.

Social inequalities in health: a proper concern of epidemiology.

Science.gov (United States)

Marmot, Michael; Bell, Ruth

2016-04-01

Social inequalities are a proper concern of epidemiology. Epidemiological thinking and modes of analysis are central, but epidemiological research is one among many areas of study that provide the evidence for understanding the causes of social inequalities in health and what can be done to reduce them. Understanding the causes of health inequalities requires insights from social, behavioral and biological sciences, and a chain of reasoning that examines how the accumulation of positive and negative influences over the life course leads to health inequalities in adult life. Evidence that the social gradient in health can be reduced should make us optimistic that reducing health inequalities is a realistic goal for all societies. Copyright © 2016 Elsevier Inc. All rights reserved.

Teaching Epidemiology at the Undergraduate Level: Considerations and Approaches.

Science.gov (United States)

Goldmann, Emily; Stark, James H; Kapadia, Farzana; McQueen, Matthew B

2018-06-01

The rapid growth in undergraduate public health education has offered training in epidemiology to an increasing number of undergraduate students. Epidemiology courses introduce undergraduate students to a population health perspective and provide opportunities for these students to build essential skills and competencies such as ethical reasoning, teamwork, comprehension of scientific methods, critical thinking, quantitative and information literacy, ability to analyze public health information, and effective writing and oral communication. Taking a varied approach and incorporating active learning and assessment strategies can help engage students in the material, improve comprehension of key concepts, and further develop key competencies. In this commentary, we present examples of how epidemiology may be taught in the undergraduate setting. Evaluation of these approaches and others would be a valuable next step.

Perspectives on emerging zoonotic disease research and capacity building in Canada

Science.gov (United States)

Stephen, Craig; Artsob, Harvey; Bowie, William R; Drebot, Michael; Fraser, Erin; Leighton, Ted; Morshed, Muhammad; Ong, Corinne; Patrick, David

2004-01-01

Zoonoses are fundamental determinants of community health. Preventing, identifying and managing these infections must be a central public health focus. Most current zoonoses research focuses on the interface of the pathogen and the clinically ill person, emphasizing microbial detection, mechanisms of pathogenicity and clinical intervention strategies, rather than examining the causes of emergence, persistence and spread of new zoonoses. There are gaps in the understanding of the animal determinants of emergence and the capacity to train highly qualified individuals; these are major obstacles to preventing new disease threats. The ability to predict the emergence of zoonoses and their resulting public health and societal impacts are hindered when insufficient effort is devoted to understanding zoonotic disease epidemiology, and when zoonoses are not examined in a manner that yields fundamental insight into their origin and spread. Emerging infectious disease research should rest on four pillars: enhanced communications across disciplinary and agency boundaries; the assessment and development of surveillance and disease detection tools; the examination of linkages between animal health determinants of human health outcomes; and finally, cross-disciplinary training and research. A national strategy to predict, prevent and manage emerging diseases must have a prominent and explicit role for veterinary and biological researchers. An integrated health approach would provide decision makers with a firmer foundation from which to build evidence-based disease prevention and control plans that involve complex human/animal/environmental systems, and would serve as the foundation to train and support the new cadre of individuals ultimately needed to maintain and apply research capacity in this area. PMID:18159512

Uncertainty in adaptive capacity

International Nuclear Information System (INIS)

Neil Adger, W.; Vincent, K.

2005-01-01

The capacity to adapt is a critical element of the process of adaptation: it is the vector of resources that represent the asset base from which adaptation actions can be made. Adaptive capacity can in theory be identified and measured at various scales, from the individual to the nation. The assessment of uncertainty within such measures comes from the contested knowledge domain and theories surrounding the nature of the determinants of adaptive capacity and the human action of adaptation. While generic adaptive capacity at the national level, for example, is often postulated as being dependent on health, governance and political rights, and literacy, and economic well-being, the determinants of these variables at national levels are not widely understood. We outline the nature of this uncertainty for the major elements of adaptive capacity and illustrate these issues with the example of a social vulnerability index for countries in Africa. (authors)

Epidemiology of systemic mastocytosis in Denmark

DEFF Research Database (Denmark)

Cohen, Sarah; Hoffmann, Stine Skovbo; Vestergaard, Hanne

2014-01-01

Mastocytosis is a heterogeneous group of diseases characterized by abnormal proliferation of mast cells. Systemic mastocytosis (SM), in which abnormal mast cells are present in tissues beyond the skin, is divided into seven subcategories with varying degrees of severity and prognosis. Very little......%), followed by SM with subtype unknown (n = 61; 11%), SM with associated clonal haematological non-mast cell lineage disease (n = 24; 4%), aggressive SM (n = 8; 2%), and mast cell leukaemia (n = 5; 1%). The incidence rate for SM (all subtypes including urticaria pigmentosa) was 0_89 per 100 000 per year...... to be overall relatively rare with notable variation by subtype for patient characteristics, survival and epidemiological measures. Keywords: aggressive systemic mastocytosis, indolent systemic mastocytosis, urticaria pigmentosa, epidemiology, Denmark....

L'espace articulaire de la Robotique Industrielle est un espace vectorielIndustrial Robotics joint space is a vector space

Science.gov (United States)

Tondu, Bertrand

2003-05-01

The mathematical modelling of industrial robots is based on the vectorial nature of the n-dimensional joint space of the robot, defined as a kinematic chain with n degrees of freedom. However, in our opinion, the vectorial nature of the joint space has been insufficiently discussed in the literature. We establish the vectorial nature of the joint space of an industrial robot from the fundamental studies of B. Roth on screws. To cite this article: B. Tondu, C. R. Mecanique 331 (2003).

Anticholinesterase pesticides: metabolism, neurotoxicity, and epidemiology

National Research Council Canada - National Science Library

Satoh, Tetsuo, Ph. D; Gupta, Ramesh C

2010-01-01

.... The early portion of the book deals with metabolism, mechanisms and biomonitoring of anticholinesterase pesticides, while the later part deals with epidemiological studies, regulatory issues, and therapeutic intervention"--Provided by publisher.

Research Methods in Healthcare Epidemiology: Survey and Qualitative Research.

Science.gov (United States)

Safdar, Nasia; Abbo, Lilian M; Knobloch, Mary Jo; Seo, Susan K

2016-11-01

Surveys are one of the most frequently employed study designs in healthcare epidemiology research. Generally easier to undertake and less costly than many other study designs, surveys can be invaluable to gain insights into opinions and practices in large samples and may be descriptive and/or be used to test associations. In this context, qualitative research methods may complement this study design either at the survey development phase and/or at the interpretation/extension of results stage. This methods article focuses on key considerations for designing and deploying surveys in healthcare epidemiology and antibiotic stewardship, including identification of whether or not de novo survey development is necessary, ways to optimally lay out and display a survey, denominator measurement, discussion of biases to keep in mind particularly in research using surveys, and the role of qualitative research methods to complement surveys. We review examples of surveys in healthcare epidemiology and antimicrobial stewardship and review the pros and cons of methods used. A checklist is provided to help aid design and deployment of surveys in healthcare epidemiology and antimicrobial stewardship. Infect Control Hosp Epidemiol 2016;1-6.

PERHITUNGAN IDLE CAPACITY DENGAN MENGGUNAKAN CAM-I CAPACITY MODEL DALAM RANGKA EFISIENSI BIAYA PADA PT X

Directory of Open Access Journals (Sweden)

Muammar Aditya

2015-09-01

Full Text Available Aim for this research are to analyze capacity cost which incure from company production machines and human resources whose operate the production machine using CAM-I capacity model. CAM-I capacity model is an approach which focus  upon how to manage company resources. This research initiated at PT X which focus to production activity that used small mixer machine, extruder machine, oven drying machine, enrober machine, pan coting machine which consist of hot and cold pan coating machine, and packing machine which consist of vertical packing machine and horizontal packing machine as well as human resources that operates those machine. This research focus on rate capacity, productive capacity, idle capacity, and nonproductive capacity to measure capacity cost. Result of this research shows most of the capacity owned by either by production machine or human resources are not utilized to its maximum potential. There are need to reduce capacity cost owned by production machine and human resoures to increase the product sales but if its unachieveable there will be need to increase efficiency from production machine and human resources by reducing their quantityDOI: 10.15408/ess.v4i1.1961

Epidemiology as a liberal art: from graduate school to middle school, an unfulfilled agenda.

Science.gov (United States)

Bracken, Michael B

2014-03-01

Calls by Lilienfeld, Fraser, and others some three decades ago to introduce epidemiology into undergraduate college education remain largely unfulfilled. Consideration of epidemiology as a "liberal art" has also led to exploring possibilities for introducing epidemiology into early education: to high and even middle schools. Adding epidemiology to school curricula should help educate the public to understand science-based evidence concerning the causes and treatments of disease, help inoculate them against a tsunami of biased and fraudulent media messaging, and permit advancing postgraduate education in epidemiology to even higher levels of scholarship. Copyright © 2014 Elsevier Inc. All rights reserved.

Improving Decision-Making Activities for Meningitis and Malaria

Science.gov (United States)

Ceccato, P.; Trzaska, S.; Perez, C.; Kalashnikova, O. V.; del Corral, J.; Cousin, R.; Blumenthal, M. B.; Connor, S.; Thomson, M. C.

2012-12-01

Public health professionals are increasingly concerned about the potential impact that climate variability and change can have on infectious disease. The International Research Institute for Climate and Society (IRI) is developing new products to increase the public health community's capacity to understand, use, and demand the appropriate climate data and climate information to mitigate the public health impacts of climate on infectious disease, in particular Meningitis and Malaria. In this paper we present the new and improved products that have been developed for monitoring dust, temperature, rainfall and vectorial capacity model for monitoring and forecasting risks of Meningitis and Malaria epidemics. We also present how the products have been integrated into a knowledge system (IRI Data Library Map room, SERVIR) to support the use of climate and environmental information in climate-sensitive health decision-making.

Killing fields; The epidemiological evidence

Energy Technology Data Exchange (ETDEWEB)

Best, Simon

1990-02-01

The threat posed by low frequency fields emerged initially because a researcher, looking for environmental factors in childhood leukaemia, observed a link between low voltage, high current power lines and disease occurrence. Cellular evidence now supports the findings but epidemiology still leads the argument. (43 references). (author).

Epidemiological data and radiation risk estimates

International Nuclear Information System (INIS)

Cardis, E.

2002-01-01

The results of several major epidemiology studies on populations with particular exposure to ionizing radiation should become available during the first years of the 21. century. These studies are expected to provide answers to a number of questions concerning public health and radiation protection. Most of the populations concerned were accidentally exposed to radiation in ex-USSR or elsewhere or in a nuclear industrial context. The results will complete and test information on risk coming from studies among survivors of the Hiroshima and Nagasaki atomic bombs, particularly studies on the effects of low dose exposure and prolonged low-dose exposure, of different types of radiation, and environmental and host-related factors which could modify the risk of radiation-induced effects. These studies are thus important to assess the currently accepted scientific evidence on radiation protection for workers and the general population. In addition, supplementary information on radiation protection could be provided by formal comparisons and analyses combining data from populations with different types of exposure. Finally, in order to provide pertinent information for public health and radiation protection, future epidemiology studies should be targeted and designed to answer specific questions, concerning, for example, the risk for specific populations (children, patients, people with genetic predisposition). An integrated approach, combining epidemiology and studies on the mechanisms of radiation induction should provide particularly pertinent information. (author)

Epidemiological studies on syncope--a register based approach

DEFF Research Database (Denmark)

Ruwald, Martin Huth

2013-01-01

of the patients play an essential role. In epidemiology these factors have major impact on the outcome of the patients. Until recently, even the definition of syncope, differed from one study to another which has made literature reviews difficult. Traditionally the data on epidemiology of syncope has been taken......: 1) the use, validity and accuracy of the ICD-10 diagnosis of syncope R55.9 in the National Patient Registry for the use of this diagnosis in the epidemiology of syncope, 2) diagnostics used and etiology of a random selection of patients who had a discharge diagnosis of R55.9, 3) the incidence...... thesis demonstrated that the ICD-10 discharge diagnosis could reliably identify a cohort of patients admitted for syncope and that the discharge code carried a high number of unexplained cases despite use of numerous tests. The last studies showed that syncope is a common cause for hospital contact...

Update on the epidemiology of the rheumatic diseases.

Science.gov (United States)

Gabriel, S E

1996-03-01

Epidemiologic studies continue to enhance our understanding of the rheumatic diseases. Such studies now indicate that 26 million American women are at risk for osteoporotic fractures. Contrary to previous recommendations, the identification and treatment of patients at risk for osteoporosis may be valuable even among very elderly people. Other epidemiologic studies suggest that the incidence of rheumatoid arthritis is decreasing and that it is a more benign disease than previously recognized. Osteoarthritis remains a leading cause of physical and work disability in North America. The roles of occupational physical activity, obesity, and highly competitive (though not low-impact) exercise as risk factors for osteoarthritis continue to be explored. Pharmacoepidemiologic research has recently demonstrated that a policy of prior authorization for prescription of nonsteroidal anti-inflammatory drugs may be highly cost effective. Finally, controlled epidemiologic studies have not confirmed an association between silicone breast implants and connective tissue diseases, a conclusion recently endorsed by the American College of Rheumatology.

Epidemiology, hunger and development

Directory of Open Access Journals (Sweden)

Paulo H. Battaglin Machado

2008-06-01

Full Text Available Understanding the relationship between epidemiology and food security implies in disclosing famine causes, the way it is distributed in the society and to which extent it affects the populations. Building up from that perspective, this paper attempts to understand the famine logic throughout the various transitions accomplished in the past decades: epidemiologic, demographic, risk, nutritional and development. The reflexes of the demographic transition that took place in Brazil in the XXth century are related to the population nutritional status standard changes, that is, they shifted from malnutrition high prevalence to a significant increase in obesity. However, the paradox of this situation is due to the fact that most risk factors that bring about diseases of the modern world come from the “excess”, while millions die around the globe because of “deprivation”. The food production alone does not ensure its equitable distribution among the various groups of the society. The access alone does not lead to quality. The choices are made individually, but life style options imply in a set of correlations that go from economy to culture. It means that this field has a collective basis and encompasses environment and development.

Social epidemiology and political economy: ICU as point of convergence

Directory of Open Access Journals (Sweden)

Segura, Omar

2016-10-01

Full Text Available Questions around epidemiology, economics and critical care are often in the mind of almost any healthcare professional. However, it is seldom realized that epidemiology and economy may converge -in spite of being apparently separated fields of study- in order to explain the present situation or future trends of a hospital or public health service. This essay briefly depicts how social epidemiology and political economy have developed and how both academic activities may find a common ground about the Intensive Care Unit (ICU, particularly to pose questions, to create possible research lines and feasible alternatives towards more efficient, effective and humane health services.

Anticholinesterase pesticides: metabolism, neurotoxicity, and epidemiology

National Research Council Canada - National Science Library

Satoh, Tetsuo, Ph. D; Gupta, Ramesh C

2010-01-01

...; and epidemiology of poisonings and fatalities in people from short- and long- term exposures to these pesticides in different occupational settings on a individual country basis as well as on a global basis...

The role of epigenetics in genetic and environmental epidemiology.

Science.gov (United States)

Ladd-Acosta, Christine; Fallin, M Daniele

2016-02-01

Epidemiology is the branch of science that investigates the causes and distribution of disease in populations in order to provide preventative measures and promote human health. The fields of genetic and environmental epidemiology primarily seek to identify genetic and environmental risk factors for disease, respectively. Epigenetics is emerging as an important piece of molecular data to include in these studies because it can provide mechanistic insights into genetic and environmental risk factors for disease, identify potential intervention targets, provide biomarkers of exposure, illuminate gene-environment interactions and help localize disease-relevant genomic regions. Here, we describe the importance of including epigenetics in genetic and environmental epidemiology studies, provide a conceptual framework when considering epigenetic data in population-based studies and touch upon the many challenges that lie ahead.

Epidemiological review of human and animal fascioliasis in Egypt.

Science.gov (United States)

Soliman, Maha F M

2008-06-01

One of the neglected food-borne-diseases in the international public health arena is fascioliasis. It is a serious infectious parasitic disease infecting humans and animals worldwide and tops all the zoonotic helminthes. Human cases are being increasingly reported from Europe, the Americas, Oceania, Africa and Asia. Hence, human fascioliasis is considered now as a zoonosis of major global and regional importance. In Egypt, animal and human fascioliasis is an endemic clinical and epidemiological health problem. Doubtless, understanding the epidemiology of the parasitic diseases and factors affecting their incidence provides the foundation upon which effective prevention and control programs should be established. This article reviews the history, life cycles, transmission, incidence, geographical distribution, and environmental and human determinants that contribute to the epidemiological picture of fascioliasis with special reference to Egypt.

Toward systems epidemiology of coffee and health.

Science.gov (United States)

Cornelis, Marilyn C

2015-02-01

Coffee is one of the most widely consumed beverages in the world and has been associated with many health conditions. This review examines the limitations of the classic epidemiological approach to studies of coffee and health, and describes the progress in systems epidemiology of coffee and its correlated constituent, caffeine. Implications and applications of this growing body of knowledge are also discussed. Population-based metabolomic studies of coffee replicate coffee-metabolite correlations observed in clinical settings but have also identified novel metabolites of coffee response, such as specific sphingomyelin derivatives and acylcarnitines. Genome-wide analyses of self-reported coffee and caffeine intake and serum levels of caffeine support an overwhelming role for caffeine in modulating the coffee consumption behavior. Interindividual variation in the physiological exposure or response to any of the many chemicals present in coffee may alter the persistence and magnitude of their effects. It is thus imperative that future studies of coffee and health account for this variation. Systems epidemiological approaches promise to inform causality, parse the constituents of coffee responsible for health effects, and identify the subgroups most likely to benefit from increasing or decreasing coffee consumption.

Acute kidney injury: definition, epidemiology, and outcome.

Science.gov (United States)

Srisawat, Nattachai; Kellum, John A

2011-12-01

Acute kidney injury (AKI) is a common clinical syndrome whose definition has standardized as a result of consensus by leading experts around the world. As a result of these definitions, reported AKI incidences can now be compared across different populations and settings. Evidence from population-based studies suggests that AKI is nearly as common as myocardial infarction, at least in the western world. This review aims to highlight the recent advances in AKI epidemiology as well as to suggest future directions for prevention and management. This review will focus on the recent studies exploring the AKI epidemiology in and outside the ICU. In particular, the risk of AKI in less severe sepsis is notable as is evidence linking AKI to chronic kidney disease. New emphasis on renal recovery is shaping current thinking as is the use and utility of new biomarkers. This article reviews the recent information about the definition, classification, and epidemiology of AKI. Although new biomarkers are being developed, the 'tried and true' markers of serum creatinine and urine output, disciplined by current criteria, will be important components in the definition and classification of AKI for some time to come.

Does the recent evolution of Canadian mortality agree with the epidemiologic transition theory?

Directory of Open Access Journals (Sweden)

Robert Choinière

2008-06-01

Full Text Available After studying the epidemiologic transition's situation in Canada, it is determined that the delimitation of temporal stages within the epidemiologic transition as put forward by Omran (1971, 1998, Olshansky and Ault (1986, Rogers and Hackenberg (1987 and Olshansky et al. (1998 does not suit the Canadian evolution. Many of the researchers' postulates on the epidemiologic transition were not confirmed, which leads us to assert that, since 1958, the epidemiologic transition is best described as an evolution process rather than specific stages confined within time limits.

Epidemiologic research programs at the Department of Energy: Looking to the future

International Nuclear Information System (INIS)

1994-01-01

The secretary of the Department of Energy (DOE) asked the National Research Council in 1989 to establish a Committee on Radiation Epidemiological Research Programs to provide scientific advice on the current status and future direction of DOE's epidemiologic research program. This report is in response to a request from the National Research Council committee to provide advice regarding the future directions of OEHS's epidemiologic research. This report begins with some of the background leading to the current activities of OEHS. In 1990, a committee (the Secretarial Panel for the Evaluation of Epidemiological Research Activities, or SPEERA) established by the secretary of the DOE recommended that DOE enter into a memorandum of understanding (MoU) with the Department of Health and Human Services that outlined the responsibilities of the two departments regarding epidemiologic research. The present report points out that the implementation of the SPEERA recommendations and the MoU by DOE have raised issues that have not been satisfactorily resolved

Molecular epidemiology of Mycobacterium tuberculosis complex in Brussels, 2010-2013.

Directory of Open Access Journals (Sweden)

Christelle Vluggen

Full Text Available The tuberculosis (TB incidence rate in Brussels-Capital Region is 3-fold higher than in Belgium as a whole. Eight years after the realization of initial prospective population-based molecular epidemiology investigations in this Region, a similar study over the period 2010-2013 was conducted. TB strains isolated from 945 patients were submitted to genotyping by standardized 24-locus-MIRU-VNTR typing and spoligotyping. The phylogenetic analysis showed that the LAM (16.7% and Haarlem (15.7% branches are the two most prevalent TB lineages circulating in Brussels. Analysis of the MDR subgroup showed an association with Beijing strains (39.9% and patients native of Eastern Europe (40.7%. Genotyping detected 113 clusters involving 321 patients, giving a recent transmission index of 22.9%. Molecular-guided epidemiological investigations and routine surveillance activities revealed family transmission or social contact for patients distributed over 34 clusters. Most of the patients were foreign-born (75.7%. However, cluster analysis revealed only limited trans-national transmission. Comparison with the previous study shows a stable epidemiological situation except for the mean age difference between Belgian-born and foreign-born patients which has disappeared. This study confirms that molecular epidemiology has become an important determinant for TB control programs. However, sufficient financial means need to be available to perform all required epidemiological investigations.

A Fantastic Epidemiology Journey: from China to Africa and back

Science.gov (United States)

Dr. Ann Hsing is a professor of medicine at Stanford University and a co-leader of the Population Sciences Program at Stanford Cancer Institute. She is also a professor in the Department of Health Research and Policy (epidemiology, by courtesy) and a faculty fellow for the Center for Innovation in Global Health. In addition, she chairs the Pacific Rim Alliance for Population Health at Stanford’s Center for Population Health Sciences. Prior to joining Stanford School of Medicine, Dr. Hsing served four years as Chief Scientific Officer at the Cancer Prevention Institute of California and 22 years as an intramural scientist (tenured senior investigator) at the Division of Cancer Epidemiology and Genetics, National Cancer Institute. Dr. Hsing received her PhD in epidemiology from the Johns Hopkins University and is widely recognized as a leading expert in the epidemiology of prostate and hepatobiliary cancer, as well as hormonal carcinogenesis and molecular epidemiology. She has authored more than 280 peer-reviewed articles and mentored over 60 pre- and post-doctoral fellows and junior scholars. At Stanford, she leads the Liver Cancer Working Group and the LDCT Screening Group, and serves as the principal investigator (PI) for wellness cohort studies in China, Taiwan, and Singapore as well as liver cancer studies in the Bay area, Taiwan, Mongolia, and Africa.

Clinical epidemiology in the era of big data: new opportunities, familiar challenges

OpenAIRE

Ehrenstein,Vera; Nielsen,Henrik; Pedersen,Alma B; Johnsen,Søren P; Pedersen,Lars

2017-01-01

Vera Ehrenstein, Henrik Nielsen, Alma B Pedersen, Søren P Johnsen, Lars Pedersen Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus N, Denmark Abstract: Routinely recorded health data have evolved from mere by-products of health care delivery or billing into a powerful research tool for studying and improving patient care through clinical epidemiologic research. Big data in the context of epidemiologic research means large interlinkable data s...

Installed capacity in New York

International Nuclear Information System (INIS)

Charlton, J.

2006-01-01

This presentation discussed capacity issues related to the New York Independent System Operator (NYISO). The NYISO's market volume was approximately $11 billion in 2005, and it was responsible for providing 32,075 MW of electricity at peak load to its users. Regulatory uncertainty is currently discouraging investment in new generating resources. All load serving entities are required to contract for sufficient capacity in order to meet their capacity obligations. Market participants currently determine capacity and energy revenues. The NYISO market allows suppliers to recover variable costs for providing ancillary services, and the economic value of the revenue source governs decisions made in the wholesale electricity market. The installed capacity market was designed as a spot auction deficiency auction. Phased-in demand curves are used to modify the installed capacity market's design. A sloped demand curve mechanism is used to value capacity above the minimum requirement for both reliability and competition. Participation in the day-ahead market enhances competition and exerts downward pressure on energy and ancillary service market prices. It was concluded that the market structures and design features of the installed capacity markets recognize the need for system reliability in addition to encouraging robust competition and recognizing energy price caps and regulatory oversights. tabs., figs

Demographic and epidemiological characteristics of HIV ...

African Journals Online (AJOL)

Department of Epidemiology and Medical Statistics, College of Medicine, University of Ibadan, Ibadan, Nigeria ... Methods: Analysis of data extracted from electronic records of 17, 312 .... system for the purpose of privacy and confidentiality of.

Mathematical and statistical approaches to AIDS epidemiology

CERN Document Server

1989-01-01

The 18 research articles of this volume discuss the major themes that have emerged from mathematical and statistical research in the epidemiology of HIV. The opening paper reviews important recent contributions. Five sections follow: Statistical Methodology and Forecasting, Infectivity and the HIV, Heterogeneity and HIV Transmission Dynamics, Social Dynamics and AIDS, and The Immune System and The HIV. In each, leading experts in AIDS epidemiology present the recent results. Some address the role of variable infectivity, heterogeneous mixing, and long periods of infectiousness in the dynamics of HIV; others concentrate on parameter estimation and short-term forecasting. The last section looks at the interaction between the HIV and the immune system.

Manipulating small ruminant parasite epidemiology through the combination of nutritional strategies.

Science.gov (United States)

Houdijk, Jos G M; Kyriazakis, Ilias; Kidane, Alemayehu; Athanasiadou, Spiridoula

2012-05-04

It is increasingly being recognized that non-chemical parasite control strategies may need to be combined to control more effectively gastrointestinal parasitism, result in resilient production systems and reduce reliance on anthelmintics. Here, we consider if and how metabolizable protein (MP) supplementation and anti-parasitic plant secondary metabolites (PSM) may modulate parasite epidemiology through intervention in pasture contamination, development of infection on pasture and larval challenge as target processes. We then propose that combining two or more non-chemical parasite control strategies may have additive effects on host resistance, especially if the individual strategies target different drivers of parasite epidemiology, different processes in the parasite life cycle or different phases of acquired immunity to parasites. This epidemiological framework is used to review recent findings on combining maternal MP supplementation and grazing the PSM-rich bioactive forage chicory as an example of combining nutritional treatments to manipulate parasite epidemiology in a temperate production system. In the absence of available data for combined nutritional strategies in tropical production systems, we make predictions on the consequences of combining such strategies in these systems. We conclude that currently published studies on combining nutritional strategies under temperate conditions show potential to improve additively host resilience and reduce reliance on anthelmintics; however, effects on epidemiology have to date not shown the additive results hypothesized. The framework developed may assist further in evaluating combined (nutritional) strategies to manipulate parasite epidemiology. Copyright © 2011 Elsevier B.V. All rights reserved.

Candida infections : detection and epidemiology

NARCIS (Netherlands)

Borst, A. (Annemarie)

2002-01-01

Despite the fact that the yeast Candida is the number 4 cause of bloodstream infections in the United States and ranks number 8 in Europe, adequate detection methods are lacking. Furthermore, relatively little is known about the epidemiology of Candida. Our aim was to improve the detection and

[To the 90th anniversary of State Sanitary Epidemiologic Service Formation in Russian Federation].

Science.gov (United States)

Beliaev, E N; Podunova, L G

2012-01-01

State Educational Institution of Higher Professional Training of the Ministry of Health Care and Social Development Foundation of Russian Sanitary Epidemiologic Service dates back to September, 15, 1922, when a Decree on Sanitary Institutions of the Republic was signed. Afterwards the institutions of Sanitary Epidemiologic Service were improved: foundation of State Sanitary Inspectorate (1933-1951), approval of new concept of the Service and intensification of State Sanitary Inspectorate (1951-1991), foundation of State Sanitary Epidemiologic Service, centralization of management and financing of the Service, formation of Sanitary Epidemiologic Legislation (1991-2004), further restructurization of Sanitary Epidemiologic Service in accordance with administrative changes in Russia (2004 until now).

Population health and status of epidemiology in Western European, Balkan and Baltic countries.

Science.gov (United States)

Seniori Costantini, Adele; Gallo, Federica; Pega, Frank; Saracci, Rodolfo; Veerus, Piret; West, Robert

2015-02-01

This article is part of a series commissioned by the International Epidemiological Association, aimed at describing population health and epidemiological resources in the six World Health Organization (WHO) regions. It covers 32 of the 53 WHO European countries, namely the Western European countries, the Balkan countries and the Baltic countries. The burdens of mortality and morbidity and the patterns of risk factors and inequalities have been reviewed in order to identify health priorities and challenges. Literature and internet searches were conducted to stock-take epidemiological teaching, research activities, funding and scientific productivity. These countries have among the highest life expectancies worldwide. However, within- and between-country inequalities persist, which are largely due to inequalities in distribution of main health determinants. There is a long tradition of epidemiological research and teaching in most countries, in particular in the Western European countries. Cross-national networks and collaborations are increasing through the support of the European Union which fosters procedures to standardize educational systems across Europe and provides funding for epidemiological research through framework programmes. The number of Medline-indexed epidemiological research publications per year led by Western European countries has been increasing. The countries accounts for nearly a third of the global epidemiological publication. Although population health has improved considerably overall, persistent within- and between-country inequalities continue to challenge national and European health institutions. More research, policy and action on the social determinants of health are required in the region. Epidemiological training, research and workforce in the Baltic and Balkan countries should be strengthened. European epidemiologists can play pivotal roles and must influence legislation concerning production and access to high-quality data. © The

Capacity planning and management

OpenAIRE

Boydell, Briony

2011-01-01

After reading this chapter you should be able to: • Define and measure capacity and appreciate the factors that influence it. • Assess the difficulties of matching capacity to demand. • Evaluate and apply the different strategies for matching capacity with demand in the short, medium and long term. • Analyse the impact of constraints and bottlenecks on a process and consider the Theory of Constraints. • Outline the different strategies available for both manufacturing and service operations. ...

Epidemiology and effects on health of low ionizing radiation doses

International Nuclear Information System (INIS)

Rodriguez Artalejo, F.; Andres Manzano, B. de; Rel Calero, J. del

1997-01-01

This article describes the concept and aims of epidemiology, its methods and contribution to the knowledge of the effects of low ionizing radiation doses on health. The advantages of epidemiological studies for knowing the consequences of living near nuclear facilities and the effects of occupational exposure to radiations are also described. (Author) 43 refs

EPIDEMIOLOGY OF CHOLERA OUTBREAK IN KAMPALA ...

African Journals Online (AJOL)

hi-tech

77 No. 7 July 2000. EPIDEMIOLOGY OF CHOLERA OUTBREAK IN KAMPALA, UGANDA ... spread much (106 cases in 1995), resulting in a low level of immunity ... An intensive social ... development of a network of community health workers,.

Short term clearing of capacity markets : an alternative approach to capacity pricing

NARCIS (Netherlands)

Sadeghi, Ariobarzan; Torbaghan, Shahab Shariat; Gibescu, Madeleine

2017-01-01

In the presence of increasing penetration from renewable energy sources, several control areas in Europe and the US have introduced Capacity Remuneration Mechanisms (CRMs) to ensure sufficient investment in firm electricity generation capacity. However, due to their long-term focus, these mechanisms

Capacity Maximizing Constellations

Science.gov (United States)

Barsoum, Maged; Jones, Christopher

2010-01-01

Some non-traditional signal constellations have been proposed for transmission of data over the Additive White Gaussian Noise (AWGN) channel using such channel-capacity-approaching codes as low-density parity-check (LDPC) or turbo codes. Computational simulations have shown performance gains of more than 1 dB over traditional constellations. These gains could be translated to bandwidth- efficient communications, variously, over longer distances, using less power, or using smaller antennas. The proposed constellations have been used in a bit-interleaved coded modulation system employing state-ofthe-art LDPC codes. In computational simulations, these constellations were shown to afford performance gains over traditional constellations as predicted by the gap between the parallel decoding capacity of the constellations and the Gaussian capacity

Visual attention capacity

DEFF Research Database (Denmark)

Habekost, Thomas; Starrfelt, Randi

2009-01-01

Psychophysical studies have identified two distinct limitations of visual attention capacity: processing speed and apprehension span. Using a simple test, these cognitive factors can be analyzed by Bundesen's Theory of Visual Attention (TVA). The method has strong specificity and sensitivity......, and measurements are highly reliable. As the method is theoretically founded, it also has high validity. TVA-based assessment has recently been used to investigate a broad range of neuropsychological and neurological conditions. We present the method, including the experimental paradigm and practical guidelines...... to patient testing, and review existing TVA-based patient studies organized by lesion anatomy. Lesions in three anatomical regions affect visual capacity: The parietal lobes, frontal cortex and basal ganglia, and extrastriate cortex. Visual capacity thus depends on large, bilaterally distributed anatomical...

Ergonomics and epidemiology in evidence based health prevention

DEFF Research Database (Denmark)

Jensen, Olaf Chresten

2009-01-01

According to the definitions, ergonomics is a natural part of the health and safety activity but it has its own research methods and causal models. Public health, occupational and clinical medicines are closely related to epidemiology and differ from ergonomics by using a disease model with a wide...... success of health effects from the clinical trials could not be obtained. It is argued that the ergonomics design, Integration and Implementation can be strengthened by adapting the epidemiological methods and causal models. The ergonomics can then contribute to a common development of public health...

1995 Annual epidemiologic surveillance report for Pantex Plant

International Nuclear Information System (INIS)

1998-01-01

This report provides a summary of epidemiologic surveillance data collected from the Pantex Plant from January 1, 1995 through December 31,1995. The data were collected by a coordinator at Pantex and submitted to the Epidemiologic Surveillance Data Center,located at Oak Ridge Institute for Science and Education, where quality control procedures and data analyses were carried out. The data presented apply only to Pantex. The main sections of the report are the same as in previous years; the 1995 report provides additional information describing the work force by age and occupational groups

1995 Annual epidemiologic surveillance report for Pantex Plant

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-06-01

This report provides a summary of epidemiologic surveillance data collected from the Pantex Plant from January 1, 1995 through December 31,1995. The data were collected by a coordinator at Pantex and submitted to the Epidemiologic Surveillance Data Center,located at Oak Ridge Institute for Science and Education, where quality control procedures and data analyses were carried out. The data presented apply only to Pantex. The main sections of the report are the same as in previous years; the 1995 report provides additional information describing the work force by age and occupational groups.

Composition of Anopheles Species Collected from Selected Malarious Areas of Afghanistan and Iran

Directory of Open Access Journals (Sweden)

Helen Hoosh-Deghati

2017-10-01

Full Text Available Background: Malarious areas in Iran are close to Afghanistan and Pakistan that urge the researchers to extend their knowledge on malaria epidemiology to the neighboring countries as well. Vectorial capacity differs at species or even at population level, the first essential step is accurate identification of vectors. This study aimed to identify Anopheles species composition in selected malarious areas of Afghanistan and Iran, providing further applied data for other research in two countries.Methods: Adults Anopheles spp. were collected from four provinces in Afghanistan (Badakhshan, Herat, Kunduz, Nangarhar by pyrethrum spray catch, hand collection methods through WHO/EMRO coordination and from Chaba­har County in Iran by pyrethrum spray catch method. Identification was performed using reliable identification key.Results: Totally, 800 female Anopheles mosquitos, 400 from each country were identified at species level. Anophe­les composition in Afghanistan was An. superpictus, An. stephensi and An. hyrcanus. Most prevalent species in Ba­dakhshan and Kunduz were An. superpictus, whereas An. stephensi and An. hyrcanus were respectively found in Nangarhar and Heart. Anopheles species in Chabahar County of Iran were An. stephensi, An. fluviatilis, An. culicifa­cies and An. sergentii. The most prevalent species was An. stephensi.Conclusion: Current study provides a basis for future research such as detection of Plasmodium infection in col­lected samples which is on process by the authors, also for effective implementation of evidence-based malaria vec­tor intervention strategies.

Measurement of Radiofrequency Radiation Exposure in Epidemiological Studies (invited paper)

International Nuclear Information System (INIS)

Swerdlow, A.J.

1999-01-01

The measurement of radiofrequency (RF) exposure is important to the quality of epidemiological studies of the possible association of RF exposure with disease. The extent and type of exposure measurement in past epidemiological studies of RF, and the features of measurement that would be desirable for better studies in the future are summarised. Measurement characteristics that are discussed include quantification of radiation frequency and of intensity and timing of exposures, measurement (or good estimation) of exposures for individuals rather than only for groups, quality of measurement, and measurement of RF exposures experienced outside the study setting. Integration of exposure measurement into the design of epidemiological studies is needed for better assessments of possible RF effects. (author)

Landfill Construction and Capacity Expansion

NARCIS (Netherlands)

Andre, F.J.; Cerda, E.

2003-01-01

We study the optimal capacity and lifetime of landfills taking into account their sequential nature.Such an optimal capacity is characterized by the so-called Optimal Capacity Condition.Particular versions of this condition are obtained for two alternative settings: first, if all the landfills are

Total iron binding capacity

Science.gov (United States)

... page: //medlineplus.gov/ency/article/003489.htm Total iron binding capacity To use the sharing features on this page, please enable JavaScript. Total iron binding capacity (TIBC) is a blood test to ...

Globalization and the Changing Epidemiology of Hepatitis A Virus.

Science.gov (United States)

Jacobsen, Kathryn H

2018-03-02

Increased economic interdependence, social integration, and other aspects of globalization are contributing to significant changes in hepatitis A epidemiology. Globally, the incidence of hepatitis A virus (HAV) infection is decreasing, the age at midpoint of population immunity (AMPI) is increasing, and the proportion of symptomatic cases is increasing as the average age at infection increases. In low-income countries, HAV remains endemic but improved water and sanitation systems are reducing transmission rates among young children. In high-income countries, most adults remain susceptible to HAV and foodborne outbreaks are becoming more frequent. Middle-income countries have diverse epidemiological profiles, and they play important roles in the global spread of HAV through international trade and travel. Future changes in the epidemiology of hepatitis A will be heavily influenced by globalization processes. Copyright © 2018 Cold Spring Harbor Laboratory Press; all rights reserved.

Capacity-achieving CPM schemes

OpenAIRE

Perotti, Alberto; Tarable, Alberto; Benedetto, Sergio; Montorsi, Guido

2008-01-01

The pragmatic approach to coded continuous-phase modulation (CPM) is proposed as a capacity-achieving low-complexity alternative to the serially-concatenated CPM (SC-CPM) coding scheme. In this paper, we first perform a selection of the best spectrally-efficient CPM modulations to be embedded into SC-CPM schemes. Then, we consider the pragmatic capacity (a.k.a. BICM capacity) of CPM modulations and optimize it through a careful design of the mapping between input bits and CPM waveforms. The s...

Simulations of floor cooling system capacity

International Nuclear Information System (INIS)

Odyjas, Andrzej; Górka, Andrzej

2013-01-01

Floor cooling system capacity depends on its physical and operative parameters. Using numerical simulations, it appears that cooling capacity of the system largely depends on the type of cooling loads occurring in the room. In the case of convective cooling loads capacity of the system is small. However, when radiation flux falls directly on the floor the system significantly increases productivity. The article describes the results of numerical simulations which allow to determine system capacity in steady thermal conditions, depending on the type of physical parameters of the system and the type of cooling load occurring in the room. Moreover, the paper sets out the limits of system capacity while maintaining a minimum temperature of the floor surface equal to 20 °C. The results are helpful for designing system capacity in different type of cooling loads and show maximum system capacity in acceptable thermal comfort condition. -- Highlights: ► We have developed numerical model for simulation of floor cooling system. ► We have described floor system capacity depending on its physical parameters. ► We have described floor system capacity depending on type of cooling loads. ► The most important in the obtained cooling capacities is the type of cooling loads. ► The paper sets out the possible maximum cooling floor system capacity

Measles outbreak in adults: A changing epidemiological pattern

Directory of Open Access Journals (Sweden)

Swati Bajaj

2017-01-01

Full Text Available Background: Thirty-one cases of fever with rash were reported among students of a college in Pune, India, from March to May 2014. The clinical profile was similar to that of measles and 7 of them tested positive for measles-specific immunoglobulin M (IgM. An outbreak of measles was declared, and epidemiological investigation was carried out to assess the situation and suggest preventive measures. Methods: An epidemiological case sheet filled for each case to identify the source and likely contacts. Medical and administrative authorities were sensitized about the increase in incidence and clustering of cases. A surveillance system was set up for detection of new cases and follow-up of contacts. Throat swabs and blood samples from 12 cases were tested by ELISA method for commonly occurring viral exanthematous fevers to confirm the diagnosis and 7 were positive for measles-specific IgM antibody. Preventive measures were advised to control the outbreak. Results: A total of 31 cases of fever with rashes were reported among students of a college in Pune, India, during the months of March–May 2014. Most of the students were in the age group of 18–24 years. Samples from 12 cases were sent for testing and 7 tested positive for measles-specific IgM antibodies. Seven cases were epidemiologically linked to a lab-confirmed case. All cases had fever, maculopapular rash, and sore throat and gave a history of vaccination for measles in childhood. Conclusion: An epidemiological investigation was carried out for outbreak of measles in a young adult population of college students from Pune. It is reported that, with increase in overall coverage of vaccination, there is a rise in incidence of measles in vaccinated individuals. The age profile also shifts to higher age groups. Investigation of such outbreaks provides an opportunity to identify high-risk groups, changes in measles epidemiology and weaknesses in the routine immunization programs.

Assessment of epidemiological parameters and their use in epidemiological and forecasting models of cereal airborne diseases

DEFF Research Database (Denmark)

Vallavieille-Pope, C. de; Giosue, S.; Munk, L.

2000-01-01

Assessments of epidemiological parameters (e.g. infection efficiency, latent period, spore production) are required for the prediction of epidemic progress, for the estimation of components of partial resistance for different host plant cultivars and for the estimation of fitness components of pa...

Competitive Capacity Investment under Uncertainty

NARCIS (Netherlands)

X. Li (Xishu); R.A. Zuidwijk (Rob); M.B.M. de Koster (René); R. Dekker (Rommert)

2016-01-01

textabstractWe consider a long-term capacity investment problem in a competitive market under demand uncertainty. Two firms move sequentially in the competition and a firm’s capacity decision interacts with the other firm’s current and future capacity. Throughout the investment race, a firm can

Epidemiology and moral philosophy.

OpenAIRE

Westrin, C G; Nilstun, T; Smedby, B; Haglund, B

1992-01-01

To an increasing extent ethical controversies affect and sometimes obstruct public health work and epidemiological research. In order to improve communication between the concerned parties a model for identification and analysis of ethical conflicts in individual-based research has been worked out in co-operation between epidemiologists and moral philosophers. The model has two dimensions. One dimension specifies relevant ethical principles (as beneficence, non-maleficence, autonomy and justi...

Epidemiologic studies based on the Chernobyl accident

International Nuclear Information System (INIS)

Beebe, G.

1996-01-01

There are great opportunities in the post-Chernobyl experience for significant epidemiologic research, perhaps even more in the area of disaster research than in the area of the human health effects of ionizing radiation. But the potential opportunity for learning the effects of radioiodine on the thyroid is very great and has aroused widespread national and international investigative interest. The opportunities for significant epidemiologic research are, however, severely limited currently by the worsening economic situation in Belarus and Ukraine, where the greatest exposure occurred, and by the lack of personnel trained in appropriate methods of study, the lack of modern equipment, the lack of supplies, the poor communication facilities, and the difficulties of accurate dose estimation. the disadvantages may or may not outweigh the obvious advantages of large numbers, the extensive direct thyroidal measurements made shortly after the accident in 1986, the magnitude of the releases of radioiodine, and the retention of the former Soviet system of universal medical care. Both the European Commission (EC) and the World Health Organization (WHO) have been working actively to strengthen the infrastructure of Russia, Belarus, and Ukraine. New scientific knowledge has yet to emerge from the extensive epidemiologic work but information of considerable public health significance has begun to accumulate. The bulk of the thyroid cancer has been shown to be valid by international pathology review; both EC and WHO representatives have declared the increase in thyroid cancer among children to have been caused in large part by Chernobyl. No increase in leukemia has been seen in the general population. The WHO pilot studies have shown no evidence of an increase in psychologic or neurologic complications among those exposed in utero. Ongoing epidemiologic work can be described by review of the inventory that the WHO has begun to maintain and publish. 20 refs., 7 tabs

Clinical Epidemiology Unit - overview of research areas

Science.gov (United States)

Clinical Epidemiology Unit (CEU) conducts etiologic research with potential clinical and public health applications, and leads studies evaluating population-based early detection and cancer prevention strategies

Glossary for econometrics and epidemiology.

Science.gov (United States)

Gunasekara, F Imlach; Carter, K; Blakely, T

2008-10-01

Epidemiologists and econometricians are often interested in similar topics-socioeconomic position and health outcomes-but the different languages that epidemiologists and economists use to interpret and discuss their results can create a barrier to mutual communication. This glossary defines key terms used in econometrics and epidemiology to assist in bridging this gap.

Integrated capacity and inventory decisions

NARCIS (Netherlands)

Dellaert, N.P.; Flapper, S.D.P.; Tan, T.; Jeunet, J.; Klatte, D.; Lüthi, H.-J.; Schmedders, K.

2012-01-01

This paper deals with the simultaneous acquisition of capacity and material in a situation with uncertain demand, with non-zero lead-times for the supply of both material and capacity. Although there is a lot of literature on the time-phased acquisition of capacity and material, most of this

Capacity Building in Land Administration

DEFF Research Database (Denmark)

Enemark, Stig; Williamson, I

2004-01-01

Capacity building increasingly seen as a key component of land administration projects in developing and countries in transition undertaken by the international development banks and individual country development assistance agencies. However, the capacity building concept is often used within...... infrastructures for implementing land policies in a sustainable way. Where a project is established to create land administration infrastructures in developing or transition countries, it is critical that capacity building is a mainstream component, not as an add-on, which is often the case. In fact such projects...... should be dealt with as capacity building projects in themselves.    The article introduces a conceptual analytical framework that provides some guidance when dealing with capacity building for land administration in support of a broader land policy agenda....

Large capacity temporary visual memory

Science.gov (United States)

Endress, Ansgar D.; Potter, Mary C.

2014-01-01

Visual working memory (WM) capacity is thought to be limited to three or four items. However, many cognitive activities seem to require larger temporary memory stores. Here, we provide evidence for a temporary memory store with much larger capacity than past WM capacity estimates. Further, based on previous WM research, we show that a single factor — proactive interference — is sufficient to bring capacity estimates down to the range of previous WM capacity estimates. Participants saw a rapid serial visual presentation (RSVP) of 5 to 21 pictures of familiar objects or words presented at rates of 4/s or 8/s, respectively, and thus too fast for strategies such as rehearsal. Recognition memory was tested with a single probe item. When new items were used on all trials, no fixed memory capacities were observed, with estimates of up to 9.1 retained pictures for 21-item lists, and up to 30.0 retained pictures for 100-item lists, and no clear upper bound to how many items could be retained. Further, memory items were not stored in a temporally stable form of memory, but decayed almost completely after a few minutes. In contrast, when, as in most WM experiments, a small set of items was reused across all trials, thus creating proactive interference among items, capacity remained in the range reported in previous WM experiments. These results show that humans have a large-capacity temporary memory store in the absence of proactive interference, and raise the question of whether temporary memory in everyday cognitive processing is severely limited as in WM experiments, or has the much larger capacity found in the present experiments. PMID:23937181

Epidemiology and risk assessment for radiation

International Nuclear Information System (INIS)

Badwe, R.A.

2014-01-01

The hazard and exposures from radiation are known with reasonable accuracy. However, at 'low levels' uncertainty persists as to whether the dose response relationship is linear and whether there is a dose threshold, below which there is no risk. Some have proposed that 'low' exposures to radiation may be beneficial, a hypothesis referred to as 'hormesis'. Over recent decades, various expert groups have adopted linear no-threshold dose-response models for radiation and cancer, based on review of epidemiological and biological evidence. The unexpected epidemic of thyroid cancer among children following the Chernobyl disaster was noticed. The research with epidemiological data and knowledge of the radionuclides to which the children were exposed is needed. Currently a debate concerning potential risks of high frequency electromagnetic radiation from mobile phones illustrates another need for further research

Neuroscience-related research in Ghana: a systematic evaluation of direction and capacity.

Science.gov (United States)

Quansah, Emmanuel; Karikari, Thomas K

2016-02-01

Neurological and neuropsychiatric diseases account for considerable healthcare, economic and social burdens in Ghana. In order to effectively address these burdens, appropriately-trained scientists who conduct high-impact neuroscience research will be needed. Additionally, research directions should be aligned with national research priorities. However, to provide information about current neuroscience research productivity and direction, the existing capacity and focus need to be identified. This would allow opportunities for collaborative research and training to be properly explored and developmental interventions to be better targeted. In this study, we sought to evaluate the existing capacity and direction of neuroscience-related research in Ghana. To do this, we examined publications reporting research investigations authored by scientists affiliated with Ghanaian institutions in specific areas of neuroscience over the last two decades (1995-2015). 127 articles that met our inclusion criteria were systematically evaluated in terms of research foci, annual publication trends and author affiliations. The most actively-researched areas identified include neurocognitive impairments in non-nervous system disorders, depression and suicide, epilepsy and seizures, neurological impact of substance misuse, and neurological disorders. These studies were mostly hospital and community-based surveys. About 60% of these articles were published in the last seven years, suggesting a recent increase in research productivity. However, data on experimental and clinical research outcomes were particularly lacking. We suggest that future investigations should focus on the following specific areas where information was lacking: large-scale disease epidemiology, effectiveness of diagnostic platforms and therapeutic treatments, and the genetic, genomic and molecular bases of diseases.

Phage typing or CRISPR typing for epidemiological surveillance of Salmonella Typhimurium?

Science.gov (United States)

Mohammed, Manal

2017-11-07

Salmonella Typhimurium is the most dominant Salmonella serovar around the world. It is associated with foodborne gastroenteritis outbreaks but has recently been associated with invasive illness and deaths. Characterization of S. Typhimurium is therefore very crucial for epidemiological surveillance. Phage typing has been used for decades for subtyping of S. Typhimurium to determine the epidemiological relation among isolates. Recent studies however have suggested that high throughput clustered regular interspaced short palindromic repeats (CRISPR) typing has the potential to replace phage typing. This study aimed to determine the efficacy of high-throughput CRISPR typing over conventional phage typing in epidemiological surveillance and outbreak investigation of S. Typhimurium. In silico analysis of whole genome sequences (WGS) of well-documented phage types of S. Typhimurium reveals the presence of different CRISPR type among strains belong to the same phage type. Furthermore, different phage types of S. Typhimurium share identical CRISPR type. Interestingly, identical spacers were detected among outbreak and non-outbreak associated DT8 strains of S. Typhimurium. Therefore, CRISPR typing is not useful for the epidemiological surveillance and outbreak investigation of S. Typhimurium and phage typing, until it is replaced by WGS, is still the gold standard method for epidemiological surveillance of S. Typhimurium.

[Clostridium difficile infection: epidemiology, disease burden and therapy].

Science.gov (United States)

Gulácsi, László; Kertész, Adrienne; Kopcsóné Németh, Irén; Banai, János; Ludwig, Endre; Prinz, Gyula; Reményi, Péter; Strbák, Bálint; Zsoldiné Urbán, Edit; Baji, Petra; Péntek, Márta; Brodszky, Valentin

2013-07-28

C. difficile causes 25 percent of the antibiotic associated infectious nosocomial diarrhoeas. C. difficile infection is a high-priority problem of public health in each country. The available literature of C. difficile infection's epidemiology and disease burden is limited. Review of the epidemiology, including seasonality and the risk of recurrences, of the disease burden and of the therapy of C. difficile infection. Review of the international and Hungarian literature in MEDLINE database using PubMed up to and including 20th of March, 2012. The incidence of nosocomial C. difficile associated diarrhoea is 4.1/10 000 patient day. The seasonality of C. difficile infection is unproved. 20 percent of the patients have recurrence after metronidazole or vancomycin treatment, and each recurrence increases the chance of a further one. The cost of C. difficile infection is between 130 and 500 thousand HUF (430 € and 1665 €) in Hungary. The importance of C. difficile infection in public health and the associated disease burden are significant. The available data in Hungary are limited, further studies in epidemiology and health economics are required.

1996 Savannah River Site annual epidemiologic surveillance report

Energy Technology Data Exchange (ETDEWEB)

None

2000-03-01

This report provides a summary of epidemiologic surveillance data collected from Savannah River Site from January 1, 1996 through December 31, 1996. The data were collected by a coordinator at Savannah River Site and submitted to the Epidemiologic Surveillance Data Center located at Oak Ridge Institute for Science and Education, where quality control procedures and preliminary data analyses were carried out. The analyses were interpreted and the final report prepared by the DOE Office of Epidemiologic Studies. The information in this report provides highlights of the data analyses conducted on the 1996 data collected from Savannah River Site. The main sections of the report include: work force characteristics; absences due to injury or illness lasting 5 or more consecutive workdays; workplace illnesses, injuries, and deaths that were reportable to the Occupational Safety and Health Administration (''OSHA-recordable'' events); and disabilities and deaths among current workers. The 1996 report includes a new section on time trends that provides comparative information on the health of the work force from 1994 through 1996.

1997 Savannah River Site annual epidemiologic surveillance report

Energy Technology Data Exchange (ETDEWEB)

None

2000-06-01

This report provides a summary of epidemiologic surveillance data collected from Savannah River Site from January 1, 1997 through December 31, 1997. The data were collected by a coordinator at Savannah River Site and submitted to the Epidemiologic Surveillance Data Center located at Oak Ridge Institute for Science and Education, where quality control procedures and preliminary data analyses were carried out. The analyses were interpreted and the final report prepared by the DOE Office of Epidemiologic Studies. The information in this report provides highlights of the data analyses conducted on the 1997 data collected from Savannah River Site. The main sections of the report include: work force characteristics; absences due to injury or illness lasting 5 or more consecutive workdays; workplace illnesses, injuries, and deaths that were reportable to the Occupational Safety and Health Administration (''OSHA-recordable'' events); and disabilities and deaths among current workers. The 199 7 report includes a section on time trends that provides comparative information on the health of the work force from 1994 through 1997.

Epidemiology in wonderland: Big Data and precision medicine.

Science.gov (United States)

Saracci, Rodolfo

2018-03-01

Big Data and precision medicine, two major contemporary challenges for epidemiology, are critically examined from two different angles. In Part 1 Big Data collected for research purposes (Big research Data) and Big Data used for research although collected for other primary purposes (Big secondary Data) are discussed in the light of the fundamental common requirement of data validity, prevailing over "bigness". Precision medicine is treated developing the key point that high relative risks are as a rule required to make a variable or combination of variables suitable for prediction of disease occurrence, outcome or response to treatment; the commercial proliferation of allegedly predictive tests of unknown or poor validity is commented. Part 2 proposes a "wise epidemiology" approach to: (a) choosing in a context imprinted by Big Data and precision medicine-epidemiological research projects actually relevant to population health, (b) training epidemiologists, (c) investigating the impact on clinical practices and doctor-patient relation of the influx of Big Data and computerized medicine and (d) clarifying whether today "health" may be redefined-as some maintain in purely technological terms.

Epidemiological characteristics of Brazilian spotted fever in Minas Gerais State, Brazil, 2000-2008

Directory of Open Access Journals (Sweden)

Frederico Figueiredo Amâncio

2011-10-01

Full Text Available Brazilian spotted fever is the most common rickettsiosis in Brazil, most prevalent in the States of São Paulo and Minas Gerais. The aim of this study was to describe the epidemiological characteristics of Brazilian spotted fever in Minas Gerais from 2000 to 2008. Of the 132 cases of Brazilian spotted fever, 53 patients died, representing a case-fatality rate of 40.2%. Males predominated, with 78.8% of confirmed cases, and median age was 26.5 years. Absence of rash was associated with increased risk of death (p = 0.005. Greater Metropolitan Belo Horizonte, Rio Doce Valley, and Zona da Mata accounted for 70.6% of the cases, which occurred mainly from May to November. There was an increase in the number of cases, which could suggest an expansion of the disease, but probably resulted from an increase in the health system's diagnostic capacity and sensitivity. Despite this improvement, the case-fatality rate remains high and with no apparent tendency to decrease, thus indicating the need for improved prevention and patient care.

Gastric cancer: epidemiology, prevention, classification, and treatment

Directory of Open Access Journals (Sweden)

Sitarz R

2018-02-01

Full Text Available Robert Sitarz,1–3 Małgorzata Skierucha,1,2 Jerzy Mielko,1 G Johan A Offerhaus,3 Ryszard Maciejewski,2 Wojciech P Polkowski1 1Department of Surgical Oncology, Medical University of Lublin, Lublin, Poland; 2Department of Human Anatomy, Medical University of Lublin, Lublin, Poland; 3Department of Pathology, University Medical Centre, Utrecht, The Netherlands Abstract: Gastric cancer is the second most common cause of cancer-related deaths in the world, the epidemiology of which has changed within last decades. A trend of steady decline in gastric cancer incidence rates is the effect of the increased standards of hygiene, conscious nutrition, and Helicobacter pylori eradication, which together constitute primary prevention. Avoidance of gastric cancer remains a priority. However, patients with higher risk should be screened for early detection and chemoprevention. Surgical resection enhanced by standardized lymphadenectomy remains the gold standard in gastric cancer therapy. This review briefly summarizes the most important aspects of gastric cancers, which include epidemiology, risk factors, classification, diagnosis, prevention, and treatment. The paper is mostly addressed to physicians who are interested in updating the state of art concerning gastric carcinoma from easily accessible and credible source. Keywords: gastric cancer, epidemiology, classification, risk factors, treatment

Global epidemiology of sporotrichosis.

Science.gov (United States)

Chakrabarti, Arunaloke; Bonifaz, Alexandro; Gutierrez-Galhardo, Maria Clara; Mochizuki, Takashi; Li, Shanshan

2015-01-01

Sporotrichosis is an endemic mycosis caused by the dimorphic fungus Sporothrix schenckii sensu lato. It has gained importance in recent years due to its worldwide prevalence, recognition of multiple cryptic species within the originally described species, and its distinctive ecology, distribution, and epidemiology across the globe. In this review, we describe the current knowledge of the taxonomy, ecology, prevalence, molecular epidemiology, and outbreaks due to S. schenckii sensu lato. Despite its omnipresence in the environment, this fungus has remarkably diverse modes of infection and distribution patterns across the world. We have delved into the nuances of how sporotrichosis is intimately linked to different forms of human activities, habitats, lifestyles, and environmental and zoonotic interactions. The purpose of this review is to stimulate discussion about the peculiarities of this unique fungal pathogen and increase the awareness of clinicians and microbiologists, especially in regions of high endemicity, to its emergence and evolving presentations and to kindle further research into understanding the unorthodox mechanisms by which this fungus afflicts different human populations. © The Author 2014. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Clinical Epidemiology Of Stroke

Directory of Open Access Journals (Sweden)

Nagaraja D

2005-01-01

Full Text Available Stroke is a huge public health problem because of its high morbidity and disability. The epidemiology of stroke is of relevance to construct practical paradigms to tackle this major health issue in the community. Recent data have shown that about 72-86% of strokes are ischemic, 9-18% are due to hemorrhage (intracerebral of subarachnoid and the rest are undefined. The risk factors for stroke are multiple and combined. At present, stroke is no more considered as unavoidable and untreatable. It is an emergency and specialized units and teams improve outcome and lower costs. Death related to stroke is declining in many countries and in both sexes. This decrease in multifactorial. The detection and more effective treatment of hypertension may play an important factor, as well as the improved medical care and improvement in diagnostic procedures. While stroke incidence appears stable and stroke mortality is slowly declining, the absolute magnitude of stroke is likely to grow over the next 30 years. as the population ages, the absolute number of stroke victims and demands on healthcare and other support systems is likely to increase substantially in the future. Keeping this in perspective, this chapter shall focus on the epidemiology of stroke in the world and in Indian, in particular.

Molecular Epidemiology of Heart Failure

Directory of Open Access Journals (Sweden)

J. Gustav Smith, MD, PhD

2017-12-01

Full Text Available Heart failure (HF is the end-stage of all heart disease and arguably constitutes the greatest unmet therapeutic need in cardiovascular medicine today. Classic epidemiological studies have established clinical risk factors for HF, but the cause remains poorly understood in many cases. Biochemical analyses of small case-control series and animal models have described a plethora of molecular characteristics of HF, but a single unifying pathogenic theory is lacking. Heart failure appears to result not only from cardiac overload or injury but also from a complex interplay among genetic, neurohormonal, metabolic, inflammatory, and other biochemical factors acting on the heart. Recent development of robust, high-throughput tools in molecular biology provides opportunity for deep molecular characterization of population-representative cohorts and HF cases (molecular epidemiology, including genome sequencing, profiling of myocardial gene expression and chromatin modifications, plasma composition of proteins and metabolites, and microbiomes. The integration of such detailed information holds promise for improving understanding of HF pathophysiology in humans, identification of therapeutic targets, and definition of disease subgroups beyond the current classification based on ejection fraction which may benefit from improved individual tailoring of therapy. Challenges include: 1 the need for large cohorts with deep, uniform phenotyping; 2 access to the relevant tissues, ideally with repeated sampling to capture dynamic processes; and 3 analytical issues related to integration and analysis of complex datasets. International research consortia have formed to address these challenges and combine datasets, and cohorts with up to 1 million participants are being collected. This paper describes the molecular epidemiology of HF and provides an overview of methods and tissue types and examples of published and ongoing efforts to systematically evaluate molecular

Epidemiology of Dyslipidemia in the Asia Pacific Region

Directory of Open Access Journals (Sweden)

Chao-Feng Lin

2018-03-01

Full Text Available Summary: Dyslipidemia, including high levels of total cholesterol, low-density lipoprotein cholesterol, and triglyceride, and low levels of high-density lipoprotein cholesterol, is a major risk factor of atherosclerosis that leads to various cardiovascular diseases. This article compares the epidemiology of dyslipidemia among countries of the Asia Pacific region, including Australia, China, Indonesia, Japan, Korea, Malaysia, New Zealand, Singapore, Thailand, and Taiwan, based on public-accessible data from websites. Sources of lipid management guidelines of the countries are also summarized. Before comparing the data from each of the countries, the readers should pay attention to the impact of lipid testing methods, medication use, the year of data acquisition, the age range of the examinees, and the definition of dyslipidemia in each country. Apart from the mentioned factors that may affect the epidemiology data, some of the countries have unique features. For example, substantial ethnic differences existed in Indonesia and Malaysia; whereas the reports from China and Thailand exhibited significant regional variations. However, a common feature is that the levels of serum lipids change with age, and men and women may have quite different levels of serum lipids even of the same age range. Nevertheless, there is a lot of room for improvement in the awareness, treatment, and control rate of dyslipidemia. To reduce the prevalence of dyslipidemia and promote cardiovascular health, the epidemiological surveys of dyslipidemia and implementation of management guidelines according to their own national conditions are encouraged. Keywords: Asia Pacific region, dyslipidemia, epidemiology

Integrating remote sensing and spatially explicit epidemiological modeling

Science.gov (United States)

Finger, Flavio; Knox, Allyn; Bertuzzo, Enrico; Mari, Lorenzo; Bompangue, Didier; Gatto, Marino; Rinaldo, Andrea

2015-04-01

Spatially explicit epidemiological models are a crucial tool for the prediction of epidemiological patterns in time and space as well as for the allocation of health care resources. In addition they can provide valuable information about epidemiological processes and allow for the identification of environmental drivers of the disease spread. Most epidemiological models rely on environmental data as inputs. They can either be measured in the field by the means of conventional instruments or using remote sensing techniques to measure suitable proxies of the variables of interest. The later benefit from several advantages over conventional methods, including data availability, which can be an issue especially in developing, and spatial as well as temporal resolution of the data, which is particularly crucial for spatially explicit models. Here we present the case study of a spatially explicit, semi-mechanistic model applied to recurring cholera outbreaks in the Lake Kivu area (Democratic Republic of the Congo). The model describes the cholera incidence in eight health zones on the shore of the lake. Remotely sensed datasets of chlorophyll a concentration in the lake, precipitation and indices of global climate anomalies are used as environmental drivers. Human mobility and its effect on the disease spread is also taken into account. Several model configurations are tested on a data set of reported cases. The best models, accounting for different environmental drivers, and selected using the Akaike information criterion, are formally compared via cross validation. The best performing model accounts for seasonality, El Niño Southern Oscillation, precipitation and human mobility.

Epidemiologic research program: Selected bibliography

International Nuclear Information System (INIS)

1993-05-01

This bibliography is a current listing of scientific reports from epidemiologic and related activities sponsored by the Department of Energy. The Office of Epidemiology and Health Surveillance now is the departmental focal point for these activities and any others relating to the study of human health effects. The Office's mission is evolving to encompass the new role of the Department in environmental restoration, weapons dismantlement and nuclear material storage, and development of new energy technologies. Publications in these areas will be included in future editions of the bibliography. The present edition brings the listing up to date, and should facilitate access to specific reports. The program has been divided into several general areas of activity: the Radiation Effects Research Foundation, which supports studies of survivors of the atomic weapons in Hiroshima and Nagasaki; mortality and morbidity studies of DOE workers; studies on internally deposited alpha emitters; medical/histologic studies; studies on the genetic aspects of radiation damage; community health surveillance studies; and the development of computational techniques and of databases to make the results as widely useful as possible

Paper vs. electrons. Epidemiologic publishing in a changing world.

Science.gov (United States)

Rothenberg; Frank; Fitzmaurice

2000-10-01

PURPOSE: To present the parallel histories of epidemiologic and electronic publishing and consider positive and negative factors that might affect their amalgam.METHODS: We performed a quantitative assessment of the arc of epidemiologic publication from 1966-1999, using major self-designated epidemiologic journals as a sample, and of scholarly electronic publication from 1991-1997, based on current literature review. We use an online, paperless journal as a case study, and review selected information-technology opinion in the area.RESULTS: By traditional standards, growth in epidemiologic publication has been considerable, with the addition of six new journals since 1966. In contrast, scholarly electronic publication for the period 1991-1997 grew from 27 to 2459 journals (not all exclusively online). Positive features of electronic publishing include flexibility, shortened time to publication, freedom from fixed publication date, diversity in presentation, and instant linkage to relevant material. A case study of a new online journal illustrates the substantive power of the medium. Negative factors include restriction (or unrestricted expansion) of the audience, the potential for hasty peer review, pitfalls in establishing credibility, an emphasis on style over content, technologic dependence, and additions to the information explosion. Relative cost and archiving are still debated. In assessing the pros and cons, it is important to distinguish electronic mechanisms that facilitate publication from electronic publishing, and to appreciate the difference between moving an existing journal to the electronic medium, and creating a new online journal.CONCLUSIONS: The movement from print to internet is probably inexorable, but a headlong rush may be ill-advised. Several models for dual publishing now exist, with the expectation that many, including the journals that serve epidemiology, will do so. The ultimate configuration is difficult to predict, but likely to be

The household contact study design for genetic epidemiological studies of infectious diseases

Directory of Open Access Journals (Sweden)

Catherine eStein

2013-04-01

Full Text Available Most genetic epidemiological study designs fall into one of two categories: family-based and population-based (case-control. However, recent advances in statistical genetics call for study designs that combine these two approaches. We describe the household contact study design as we have applied it in our several years of study of the epidemiology of tuberculosis. Though we highlight its applicability for genetic epidemiological studies of infectious diseases, there are many facets of this design that are appealing for modern genetic studies, including the simultaneous enrollment of related and unrelated individuals, closely and distantly related individuals, collection of extensive epidemiologic and phenotypic data, and evaluation of effects of shared environment and gene by environment interaction. These study design characteristics are particularly appealing for current sequencing studies.

1990s: High Capacity Backbones

Indian Academy of Sciences (India)

First page Back Continue Last page Overview Graphics. 1990s: High Capacity Backbones. Backbone capacities increased from 2.5 Gb/s to 100s of Gb/s during the 1990's. Wavelength division multiplexing with 160 waves of 10 Gb/s was commercially available. Several high-capacity backbones built in the US and Europe.

Maximizing the optical network capacity.

Science.gov (United States)

Bayvel, Polina; Maher, Robert; Xu, Tianhua; Liga, Gabriele; Shevchenko, Nikita A; Lavery, Domaniç; Alvarado, Alex; Killey, Robert I

2016-03-06

Most of the digital data transmitted are carried by optical fibres, forming the great part of the national and international communication infrastructure. The information-carrying capacity of these networks has increased vastly over the past decades through the introduction of wavelength division multiplexing, advanced modulation formats, digital signal processing and improved optical fibre and amplifier technology. These developments sparked the communication revolution and the growth of the Internet, and have created an illusion of infinite capacity being available. But as the volume of data continues to increase, is there a limit to the capacity of an optical fibre communication channel? The optical fibre channel is nonlinear, and the intensity-dependent Kerr nonlinearity limit has been suggested as a fundamental limit to optical fibre capacity. Current research is focused on whether this is the case, and on linear and nonlinear techniques, both optical and electronic, to understand, unlock and maximize the capacity of optical communications in the nonlinear regime. This paper describes some of them and discusses future prospects for success in the quest for capacity. © 2016 The Authors.

Measures of Financial Capacity: A Review.

Science.gov (United States)

Ghesquiere, Angela R; McAfee, Caitlin; Burnett, Jason

2017-05-23

Capacity to manage finances and make financial decisions can affect risk for financial exploitation and is often the basis for legal determinations of conservatorship/guardianship. Several structured assessments of financial capacity have been developed, but have not been compared regarding their focus, validity, or reliability. Therefore, we conducted a review of financial capacity measures to examine these factors. We searched electronic databases, reference lists in identified articles, conference proceedings and other grey literature for measures of financial capacity. We then extracted data on the length and domains of each measure, the population for which they were intended, and their validity and reliability. We identified 10 structured measures of financial capacity. Most measures could be completed in 25-30 min, and were designed to be administered to older adults with some level of cognitive impairment. Reliability and validity were high for most. Measurement of financial capacity is complex and multidimensional. When selecting a measure of financial capacity, consideration should be made of the population of focus and the domains of capacity to be assessed. More work is needed on the cultural sensitivity of financial capacity measures, their acceptability, and their use in clinical work. Better understanding of when, and to whom, to administer different financial capacity measures could enhance the ability to accurately detect those suffering from impaired financial capacity, and prevent related negative outcomes like financial exploitation. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Use of medical imaging as an epidemiologic tracer

International Nuclear Information System (INIS)

Dartigues, J.F.

1987-01-01

Medical imaging is a source of data for clinical and epidemiological research just like any other factual information obtained during medical treatment. Medical imaging data, like any other information, are not really useful unless they are obtained in rigorously controlled and determined conditions, defined a priori in the research protocol. In order to be use as an epidemiologic tracer (that is, as a meaning of finding a given pathology in a given population and during a given time period), the imaging data have to be valid, reliable, and representative, of easy access and obtained at a low cost [fr

An Application of Epidemiological Modeling to Information Diffusion

Science.gov (United States)

McCormack, Robert; Salter, William

Messages often spread within a population through unofficial - particularly web-based - media. Such ideas have been termed "memes." To impede the flow of terrorist messages and to promote counter messages within a population, intelligence analysts must understand how messages spread. We used statistical language processing technologies to operationalize "memes" as latent topics in electronic text and applied epidemiological techniques to describe and analyze patterns of message propagation. We developed our methods and applied them to English-language newspapers and blogs in the Arab world. We found that a relatively simple epidemiological model can reproduce some dynamics of observed empirical relationships.

Epidemiology of West Nile in Europe and in the Mediterranean Basin

Czech Academy of Sciences Publication Activity Database

Calistri, P.; Giovannini, A.; Hubálek, Zdeněk; Ionescu, A.; Monaco, F.; Savini, G.; Lelli, R.

2010-01-01

Roč. 4, - (2010), s. 29-37 ISSN 1874-3579 Institutional research plan: CEZ:AV0Z60930519 Keywords : Epidemiology * Europe * West Nile * Mediterranean Basin Subject RIV: FN - Epidemiology, Contagious Diseases ; Clinical Immunology http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2878979/pdf/TOVJ-4-29.pdf

[Interaction of the bodies and institutions of the Russian Inspectorate for the protection of consumer rights and human welfare on sanitary-and-epidemiological examinations and issuing sanitary-and-epidemiological opinions].

Science.gov (United States)

Safonkina, S G

2009-01-01

The paper describes problems in the organization of the interaction of the Russian Inspectorate for the Protection of Consumer Rights and Human Welfare in Moscow and the Center for Hygiene and Epidemiology in Moscow to perform sanitary-and-epidemiological examinations and to issue sanitary-and-epidemiological opinions. The goals of setting up a one-window service and measures required for its effective work are defined. Positive results of one-window activities are shown.

Confounding and exposure measurement error in air pollution epidemiology.

Science.gov (United States)

Sheppard, Lianne; Burnett, Richard T; Szpiro, Adam A; Kim, Sun-Young; Jerrett, Michael; Pope, C Arden; Brunekreef, Bert

2012-06-01

Studies in air pollution epidemiology may suffer from some specific forms of confounding and exposure measurement error. This contribution discusses these, mostly in the framework of cohort studies. Evaluation of potential confounding is critical in studies of the health effects of air pollution. The association between long-term exposure to ambient air pollution and mortality has been investigated using cohort studies in which subjects are followed over time with respect to their vital status. In such studies, control for individual-level confounders such as smoking is important, as is control for area-level confounders such as neighborhood socio-economic status. In addition, there may be spatial dependencies in the survival data that need to be addressed. These issues are illustrated using the American Cancer Society Cancer Prevention II cohort. Exposure measurement error is a challenge in epidemiology because inference about health effects can be incorrect when the measured or predicted exposure used in the analysis is different from the underlying true exposure. Air pollution epidemiology rarely if ever uses personal measurements of exposure for reasons of cost and feasibility. Exposure measurement error in air pollution epidemiology comes in various dominant forms, which are different for time-series and cohort studies. The challenges are reviewed and a number of suggested solutions are discussed for both study domains.

[Epidemiology of rabies in Algeria].

Science.gov (United States)

Benelmouffok, A; Belkaid, M; Benhassine, M

An epidemiological study on rabies in Algeria has been carried out on data provided by the "Institut national de Santé publique" and the "Institut Pasteur d'Algérie". It showed that no region is unhurt. The animal reservoir is of the domestic type, essentially the dog. In 40% of cases, bites are due to stray dogs.

Algorithmic complexity of quantum capacity

Science.gov (United States)

Oskouei, Samad Khabbazi; Mancini, Stefano

2018-04-01

We analyze the notion of quantum capacity from the perspective of algorithmic (descriptive) complexity. To this end, we resort to the concept of semi-computability in order to describe quantum states and quantum channel maps. We introduce algorithmic entropies (like algorithmic quantum coherent information) and derive relevant properties for them. Then we show that quantum capacity based on semi-computable concept equals the entropy rate of algorithmic coherent information, which in turn equals the standard quantum capacity. Thanks to this, we finally prove that the quantum capacity, for a given semi-computable channel, is limit computable.

Epidemiology and risk factors of schizophrenia

Czech Academy of Sciences Publication Activity Database

Janoutová, J.; Janáčková, P.; Šerý, Omar; Zeman, T.; Ambrož, P.; Kovalová, M.; Vařechová, K.; Hosák, L.; Jiřík, V.; Janout, V.

2016-01-01

Roč. 37, č. 1 (2016), s. 1-8 ISSN 0172-780X R&D Projects: GA MZd NT14504 Institutional support: RVO:67985904 Keywords : schizophrenia * risk factors * epidemiology Subject RIV: FQ - Public Health Care, Social Medicine Impact factor: 0.918, year: 2016