bluuebunny/crossref_metadata_2025 huggingface dataset:
Conditions spatiales de la démocratie participative. « Meetings » à Vosloorus (Ekurhuleni, Afrique du Sud)
Authors: Gervais-Lambony Philippe
Published: January 2013

Depuis la fin de l’apartheid, une « démocratie locale participative » est mise en œuvre dans les villes d’Afrique du Sud. Localement ceci a donné lieu à l’organisation d’un nombre incalculable de « meetings ». Une très large part de ces réunions publiques a pour but de faire formuler des demandes, d’établir des listes de besoins et les hiérarchiser. A-t-on seulement affaire à une façade démocratique qui consiste à réunir des citadins et les conduire à demander ce que l’on souhaite qu’ils demandent, ce que la norme dominante rendra acceptable de demander, et en conséquence les tenir dans l’illusion qu’on les consulte ? Ceci a été largement analysé dans une perspective critique et certains auteurs (Cornwall, 2004 ; Miraftab, 2004) proposent ainsi de distinguer ces formes d’espaces de participation organisés par les autorités locales aux formes « inventées » qui seraient d’initiative citadine : les premiers sont-ils stérilisants et les seconds créatifs ? L’auteur de l’article souhaite montrer que la simple mise en présence dans un même espace de personnes diverses a des conséquences sociales importantes et que le fonctionnement de la démocratie locale a aussi des conditions spatiales trop peu souvent prises en compte à leur juste mesure. Le texte repose sur une recherche de terrain sur une longue durée (1999-2010) dans le township de Vooslorus (situé dans l’aire métropolitaine d’Ekurhuleni qui fait elle-même partie de la province du Gauteng).
Vulnérabilité du territoire littoral guyanais aux maladies infectieuses à transmission vectorielle : esquisses de problématiques et perspectives de recherches pluridisciplinaires
Authors: Morel Valérie
Published: January 2013

Vulnerability is a concept increasingly mobilized for understanding the emergence of situations of risk regardless of their nature (Beck, Glatron, 2009; Bogardi, 2004, D'Ercole, 1991; D'Ercole et al., 1994; Fabiani, Theys 1987; Fabiani, 2010, Leone 2007, Leone, Vinet, 2007, Pierrat, 2011). The use of vulnerability for the knowledge of conditions for the emergence risk of vector-borne diseases (VBD) opens a way for systemic and multidisciplinary analysis of risk that exceeds the knowledge of traditional social criteria such as age, gender, social class or level of income taken into account in epidemiological studies. If since the beginning of the nineteenth century, the anglo-aaxon work on the risks of VBD (Cohen, 2000; Daszack et al., 2000 and 2001; Hong, Lee, 2005; Midley, Thuiller, 2005, Plowright et al., 2008 ) take into account the vulnerability assessment, however the France lags behind the Haut Conseil de la santé publique wishes to catch up (Leport and Guégan, 2011). The study of territorial vulnerability of French Guiana to VBD opens new possibilities of action for the management of health risks.
Movimento estudantil brasileiro: Práticas militantes na ótica dos Novos Movimentos Sociais
Authors: Mesquita Marcos Ribeiro
Published: January 2013

Este artigo visa identificar na estrutura e organização do movimento estudantil conteúdos e formas organizativas que nos indiquem o surgimento de uma nova sociabilidade militante. Para tanto, foi necessário analisar as relações entre os diversos grupos organizados do movimento estudantil, desde os mais institucionalizados, àqueles que empreendem outras formas de fazer política. A pluralidade de expressões estudantis, de novos formatos, metodologias e pautas parecem apontar para esta sociabilidade, apesar do forte caráter tradicional que a política estudantil institucional ainda possui.
Relationship Between Amniotic Fluid Index and Ultrasound Estimated Fetal Weight in Healthy Pregnant African Women
Authors: Adeyekun Ademola A. , Awosanya Gbolahan G.
Published: January 2013

Introduction:

Fetal weight (FW) estimation in late pregnancy is an important guide in obstetric care. Amniotic fluid protects the fetus against traumatic and infective insults. There possibly exists a relationship between FW and amniotic fluid index (AFI) that can be estimated by ultrasonography.

Materials and Methods:

Two hundred and fifty-eight low-risk pregnancies were prospectively studied by means of ultrasound over a 12-month period. FW was estimated using a combination of fetal parameters; bi-parietal diameter, fetal trunk cross sectional area, and femur length. AFI was assessed using the 4-quadrant method. Spearman's correlation was used to test possible relationship between amniotic fluid indices and estimated FW pairs. The level of statistical significance was set at P ≤ 0.05.

Results:

The mean AF1 and estimated fetal weight (EFW) pairs were as follows: at 27-29 weeks the values were 172.1 mm and 1,250.2 g; at 30-32 weeks AF1 and EFW values were 170.3 mm and 1,648.0 g; at 33-35 weeks values were 162.3 mm and 2,273.5 g; at 36-38 weeks values were 144.09 mm and 2,906.1 g; at 39-40 weeks AF1 and EFW values were 125.0 mm and 3,222.6 g. Overall, there was no statistically significant relationship between AFI and EFW (P > 0.05; r = 0.241).

Conclusion:

While FW calculations and amniotic index showed variations in value in late pregnancy, there does not appear to be a linear relationship between ultrasound estimate of FW and amniotic index. The implication of this is that fetal size need not be taken into cognizance when alterations in amniotic fluid values are noted.
The Impact of a Diabetes Self-Management Education Program Provided through a Telemedicine Link to Rural California Health Care Clinics
Authors: Nuovo Jim
Published: January 2013

Background

This project investigated the impact of a DM self-management education program provided through a telemedicine link at nine rural health clinics in Northern California.

Methods

Two hundred thirty nine patients were provided with a single 2-hour class on DM delivered through a live televideo connection. Patients provided pre-intervention information on: demographics and overall health, self-care behaviors, and knowledge about DM. All participants completed a post-education survey on knowledge and self-care behaviors.

Results

There was a significant decrease in the number of patients who felt overwhelmed with their DM; pre-intervention 18.8%; post-intervention 5.4% ( P < 0.0001). Patients increased the number of days they exercised; pre-intervention 3.4 days; post-intervention 3.9 days ( P = 0.02). Patients increased the number of days they checked their feet; pre-intervention 4.2 days; post-intervention 5.6 days ( P < 0.01). Knowledge about DM improved over the study period ( P < 0.01).

Conclusions

A single 2-hour class on DM administered through a telemedicine link to patients in rural health clinics resulted in feeling less overwhelmed, more knowledgeable about DM, and demonstrated an increase in self-care behavior; ie, exercise and foot care.
Distribution and extent of Cotesia Flavipes Cameron (Hymenoptera: Braconidae) Parasitism in Northeastern Ethiopia
Authors: Dejen Asmare , Getu Emana , Azerefegne Ferdu , Ayalew Amare
Published: January 2013

The distribution and extent of parasitism of Cotesia flavipes Cameron (Hymenoptera: Braconidae) on stem borer species attacking maize and sorghum were assessed in three zones of northeastern Ethiopia. Cotesia flavipes was found to be the key larval parasitoid of cereal stem borer species in all areas surveyed. This parasitoid has been introduced into several African countries for the control of Chilo partellus in maize and sorghum, but it has never been released in Ethiopia. The survey results indicated that the distribution and extent of parasitism of Cot. flavipes followed the distribution and severity of its suitable host, C. partellus. A Cotesia flavipes parasitism rate of between 33% and 82% was recorded in sub-moist warm (lowland) AEZs of all zones. In contrast, a parasitism rate of less than 6% was recorded in moist, cool highland areas where Busseola fusca was the predominant species. Cotesia flavipes caused lower rate of parasitism on stem borers in maize (up to 72%) than that of sorghum (up to 82%) in the three zones. In summary, high rates of parasitism of Cot. flavipes were recorded in lowland areas where C. partellus was the dominant borer species and low rates of parasitism were recorded in highland areas where B. fusca was the predominant species. Cotesia flavipes caused the highest parasitism (82%) on C. partellus. This result verified that Cot. flavipes contributed to the reduction of C. partellus population in lowlands, regardless of the zone, and its rate of parasitism varied between crop stages, crop types, elevations, host, and host stages. Findings of this study have particularly relevant information on the contribution of Cot. flavipes to the population reduction of stem borers, time or stage of its occurrence in relation to host stages and crop stages, and its distribution in relation to the availability of a suitable host across each zone. In conclusion, this larval parasitoid plays an important role in reducing stem borer populations and can be used as one component of integrated stem borer management in northeastern Ethiopia.
Safety and Efficacy of Acamprosate for the Treatment of Alcohol Dependence
Authors: Yahn Stephanie L. , Watterson Lucas R. , Olive M. Foster
Published: January 2013

Acamprosate (calcium acetylhomotaurine) is an amino acid modulator that has displayed efficacy in some clinical trials in reducing craving and promoting abstinence in alcohol dependent patients following detoxification. While acamprosate is safe and generally well-tolerated, not all studies have demonstrated clinical efficacy that is superior to placebo. In addition, the precise neurochemical mechanisms of action of acamprosate have still not yet been identified. In this review, we summarize current clinical data on the safety, efficacy, and pharmacokinetic properties of acamprosate, as well theories on its potential mechanism of action. We also discuss tolerability and patient preference issues and conclude with a discussion of the place of acamprosate in addiction medicine and therapy.
Transient stability analysis with equal-area criterion for out of step detection using phasor measurement units
Authors: Abdelaziz A.Y. , Ibrahim Amr M. , Hasan Zeinab G.
Published: January 2013

The electrical power systems function as a huge interconnected network dispersed over a large area. A balance exist between generated and consumed power, any disturbance to this balance in the system caused due to change in load as well as faults and their clearance often results in electromechanical oscillations. As a result there is variation in power flow between two areas. This phenomenon is referred as Power Swing. This paper presents a transmission line protection scheme that uses measured values of the currents and voltages of the three phases of two buses (equivalent to PMU data). The measured data is transformed from time domain into phasor domain using Discrete Fourier Transform to predict whether the swing is a stable or an unstable one. The performance of the method has been tested on a simulated system using PSCAD and MATLAB software. The proposed scheme can be used for the detection of out of step condition using equal-area criterion with different types of faults at different locations and different models of transmission lines.Keywords: Phasor Measurement Unit, Global positioning  system, Transmission line protection, Power system transient stability, Discrete Fourier Transform, Equal-Area Criterion, Out of step detection
Desafios da gestão em instituições de ensino superior: um estudo de caso a partir da percepção de diretores de centro de uma IES pública do sul do Brasil
Authors: Santos Leomar dos , Bronnemann Márcia Regina
Published: January 2013

Esta pesquisa objetivou analisar os desafios de gestão a partir da percepção de diretores de centro de uma instituição de ensino superior (IES) pública do sul do Brasil no tocante a conhecimentos; avaliações de outras pessoas; tempo disponível; comprometimento dos subordinados; gestão de divergências; burocracia e centralização; e cuidados éticos. Realizou-se um estudo de caso qualitativo com coleta de dados por meio de entrevistas em profundidade com sete diretores de centro a partir de um roteiro com questões abertas, cujas respostas se submeteram à análise de conteúdo. Os principais desafios enfrentados pelos diretores de centro estão relacionados à ausência de conhecimento prévio sobre a função e sobre aspectos de gestão; ao tempo disponível para o cargo em relação às atividades que necessitam ser realizadas; e à gestão de divergências relacionais de subordinados, administrativas e pessoais. Espera-se que este estudo possa contribuir para a gestão universitária ao apontar alguns dos desafios enfrentados por gestores universitários no exercício de sua função, auxiliando-os, assim, a melhorar seus processos de preparação, bem como auxiliar as IES no acompanhamento desses profissionais. Além disso, acredita-se que se possa contribuir com a área de conhecimento ao identificar diferentes desafios e, portanto, diferentes possibilidades de temas de pesquisa em gestão universitária.
Financiamento público e expansão da educação superior federal no Brasil: o REUNI e as perspectivas para o REUNI 2
Authors: Costa Danilo de Melo , Costa Alexandre Marino , Barbosa Francisco Vidal
Published: January 2013

O ensino superior brasileiro passa por uma grande transformação que ocorre por meio de sua reestruturação bem como sua expansão. Este trabalho apresenta e analisa as ações de financiamento da expansão do ensino superior público federal no Brasil, que está pautada em dois aspectos: criação de novas universidades e reestruturação e expansão das universidades existentes. Para tanto, escolheu-se no âmbito das universidades criadas a partir do ano de 2002 a Universidade Federal da Fronteira Sul (UFFS), e no âmbito das universidades reestruturadas a Universidade Federal de Santa Catarina (UFSC). Assim, identificou-se a percepção dos dirigentes universitários e buscou-se compreender as perspectivas para o financiamento e a expansão da educação superior no Brasil juntamente aos gestores públicos do MEC. A pesquisa é do tipo exploratória com tratamento dos dados predominantemente qualitativos. Os resultados apresentam que as universidades federais estão recebendo os recursos provenientes do financiamento público e nas respectivas universidades estudadas, este fenomeno se confirmou. Todos os gestores de ambas as instituições reconheceram a importância e a grandeza de tais investimentos mas acreditam que a continuidade do programa, o Reuni 2, será o diferencial para contribuir com o desenvolvimento não só das universidades como de todo o país.
Avaliação de cursos de graduação a partir da orientação para o mercado
Authors: Basso Kenny , Antoni Verner Luis
Published: January 2013

O artigo é resultado de um estudo desenvolvido para construir e avaliar cursos de graduação a partir de seus stakeholders (profissionais, vestibulandos, alunos e professores). A pesquisa foi dividida em duas etapas, a primeira para explorar atributos relacionados a um curso de graduação, e a segunda para descrever e quantificar esses atributos de acordo com a percepção dos alunos de cursos de graduação em direito, biologia, administração e fisioterapia. Os atributos identificados (corpo docente; estrutura física; currículo) foram relacionados com indicadores de desempenho (satisfação; relação custoXbenefício; relação alunoXprofessor; envolvimento). Ainda, o artigo discute a aplicabilidade do método utilizado e a relação entre os atributos e os indicadores de desempenho na formulação de um curso de graduação orientado para o mercado.
How do tree competition and stand dynamics lead to spatial patterns in monospecific mangroves?
Authors: Khan M. N. I. , Sharma S. , Berger U. , Koedam N. , Dahdouh-Guebas F. , Hagihara A.
Published: January 2013

Abstract. Information on mangrove stand development is rare because long-term monitoring data is often lacking. Such information is important in order to plan management measures effectively. Novel approaches are required to bridge this gap of knowledge based on existing data sets. This study uses a unique combination of field data analyses with simulation experiments in order to demonstrate how information on mangrove dynamics can be extracted if data are sparse. The paper provides a~baseline characterization of stand development in a monospecific pioneer mangrove stand of Kandelia obovata. Point pattern analyses revealed that in the young stage, self-thinning has started but has not yet lead to a regularity of spatial tree distribution in the entire stand, and trees located in smaller clumps hinder each other in growth but do not lead to a significant size class differentiation. However, after ca. 2 decades the self-thinning and the size class differentiation start to become more visible. A mutual inhibition of growth was observed within 2 m circular distance (r) in the young stage and within 3 m distance after two decades of stand development as confirmed by the negative values of mark correlation function. As a stand grows older the spatial pattern of individuals become more regular from a clustered pattern. In order to understand and predict the future stand development, simulation experiments were carried out by means of the individual-based model KiWi.
Environmental controls on the thermal structure of alpine glaciers
Authors: Wilson N. J. , Flowers G. E.
Published: January 2013

Abstract. Water entrapped in glacier accumulation zones represents a significant latent heat contribution to the development of thermal structure. It also provides a direct link between glacier environments and thermal regimes. We apply a two-dimensional mechanically-coupled model of heat flow to synthetic glacier geometries in order to explore the environmental controls on flowband thermal structure. We use this model to test the sensitivity of thermal structure to physical and environmental variables and to explore glacier thermal response to environmental changes. In different conditions consistent with a warming climate, mean glacier temperature and the volume of temperate ice may either increase or decrease, depending on the competing effects of elevated meltwater production, reduced accumulation zone extent and thinning firn. For two model reference states that exhibit commonly-observed thermal structures, the fraction of temperate ice is shown to decline with warming air temperatures. Mass balance and aquifer sensitivities play an important role in determining how the englacial thermal regimes of alpine glaciers will adjust in the future.
Discusiones sobre los asientos del registro público de la propiedad inmueble
Authors: González Riega José Gerardo
Published: January 2013

DOI: http://dx.doi.org/10.5377/derecho.v0i4.936 Revista de Derecho No.4 2003 pp.13-20
La complicidad a través de acciones cotidianas o externamente neutrales
Authors: Ambos Kai
Published: January 2013

DOI: http://dx.doi.org/10.5377/derecho.v0i4.942 Revista de Derecho No.4 2003 pp.131-139
The Effect of HIV/AIDS Education on Adolescents in Trinidad and Tobago
Authors: Jones Vanessa , Modeste Naomi , Hopp Marshak Helen , Fox Curtis
Published: January 2013

Objective. This study was conducted to determine the effectiveness of an HIV/AIDS educational intervention on adolescents’ knowledge about and perceptions of susceptibility and severity of HIV/AIDS. We also examined whether providing information about assertiveness skills led to an intention to delay initiation of sexual activity. Methods. A quasi-experimental design was used to conduct this study among secondary school students in Trinidad and Tobago. The five constructs of the Health Belief Model were used to design and test the impact of the educational lessons for the intervention group while the comparison group watched one educational video about HIV over four sessions. A total of 196 secondary school students (from nine schools) between the ages of 11 and 18 years participated in the study, 92 in the intervention group and 104 in the comparison group. Results. Those in the comparison group had higher knowledge scores at posttest than the intervention group, controlling for pretest knowledge (), but those in the intervention group were more likely to plan to delay sexual initiation (). Conclusions. While knowledge scores increased for both groups, intention to delay sexual intercourse was only seen among the intervention group and within the younger age groups.
Person-Specific Face Detection in a Scene with Optimum Composite Filtering and Colour-Shape Information
Authors: Yeom Seokwon , Woo Yong-Hyun
Published: January 2013

Face detection and recognition have wide applications in robot vision and intelligent surveillance. However, face identification at a distance is very challenging because long-distance images are often degraded by low resolution, blurring and noise. This paper introduces a person-specific face detection method that uses a nonlinear optimum composite filter and subsequent verification stages. The filter's optimum criterion minimizes the sum of the output energy generated by the input noise and the input image. The composite filter is trained with several training images under long-distance modelling. The candidate facial regions are provided by the filter's outputs of the input scene. False alarms are eliminated by subsequent testing stages, which comprise skin colour and edge mask filtering tests. In the experiments, images captured by a webcam and a CCTV camera are processed to show the effectiveness of the person-specific face detection system at a long distance.
A Survey of Collective Movement of Mobile Robots
Authors: Navarro Iñaki , Matía Fernando
Published: January 2013

Collective movement of mobile robots is the problem of how to control a group of robots making them move as a group, in a cohesive way, towards a common direction. Collective movement serves not only to move a group of robots from one point to another, but to perform more complex tasks such as using the group of robots as a moving sensor array, collective mapping and searching tasks. In this article, a survey of collective movement of mobile robots is done, including a classification and characterization of its different types, a review of the most important architectures and a list of its promising applications.
Inverse Kinematic Control of Humanoids under Joint Constraints
Authors: Kim Inhyeok , Oh Jun-Ho
Published: January 2013

We propose an inverse kinematic control framework for a position controlled humanoid robot with bounded joint range, velocity, and acceleration limits. The proposed framework comprises two components, an inverse kinematics algorithm and a damping controller. The proposed IKTC (Inverse Kinematics with Task Corrections) algorithm is based on the second order task-priority method in order to ensure the velocity-continuity of the solution. When the minimum norm solution exceeds the joint bounds, the problem is treated as a quadratic optimization problem with box constraints; an optimal task correction that lets the solution satisfy the constraints is found. In order to express the three kinds of joint constraints as a second order box constraint, a novel method is also proposed. The joint stiffness of a position controlled humanoid robot necessitates a damping controller to attenuate jolts caused by repeated contacts. We design a damping controller by using an inverted pendulum model with a compliant joint that takes into account the compliance around the foot. By using ZMP [ 20 ] measurement, the proposed damping controller is applicable not only in SSP (Single Support Phase) but also in DSP (Double Support Phase). The validity of the proposed methods is shown by imitating a captured whole-body human motion with a position controlled humanoid robot.
Bluetooth Platform for Wireless Measurements Using Industrial Sensors
Authors: Tašner Tadej , Les Kristian , Lovrec Darko
Published: January 2013

The past decade has seen significant advancement in the field of mobile devices. Various smart devices such as cellular phones, tablets and PDAs have become universal tools in our everyday lives. Their versatility is based on their computing power, portability and their integration with other devices and services such as the World Wide Web. However, these smart devices have an even wider usability spectrum. They can also be used for wireless industrial measurements using existing sensors. The wireless connectivity of existing industrial sensors is achieved by equipping them with a Bluetooth module, which digitizes the data and passes it to any Bluetooth capable smart device for further processing, evaluation and logging. This paper describes the specially designed Bluetooth platform for wireless measurements all the way from the basic concept, through hardware, firmware and software implementation, to the sample tests and measurements.
A Novel Method to Radiolabel Stealth Liposome through 1,2- dimyristoyl-sn-glycero-3-phosphoethanolamine-N-DTPA with 99mTc and Biological Evaluation
Authors: Mirel Cabrera  , Alejandra Medrano  , Nicole Lecot  , Marcelo Fernandez  , Maria Moreno  , Jose A Chabalgoity  , Juan Pablo Gambini  , Omar Alonso  , Henia Balter  , Pablo Cabral
Published: January 2013

Purpose: To study surface technetium labeling of stealth DTPA-Liposomeand to evaluate its potential as a molecular imaging tracer for both normal and melanoma-bearing mice. The radiolabeling yield of liposomes was greater than 90%and showed good chemical and biological stability. Biodistribution studies in normal mice showed blood clearance with hepatic and renal depuration. Melanoma-bearing mice showed a similar pattern of biodistribution with high tumor uptake allowing tumor imaging. The developed method of surface radiolabeled DTPA-PEG-Liposomes with 99mTc was effective and stable in vivo.
Saint-Denys Garneau : le jeu de l’ironie
Authors: Mainguy Thomas
Published: January 2013

Suivant l’image de la révolution copernicienne, le présent article traite de l’ironie dans les poèmes garnéliens. Il s’agira d’abord d’évaluer le « rêve poétique » de Garneau pour comprendre l’impact de cette révolution. Selon l’allégorie formulée dans « Le jeu », la poésie constitue un espace de liberté où l’imagination ordonne et invente le monde à sa guise. On sent poindre le sentiment d’une grâce qu’on retrouvera aussi dans les « Esquisses en plein air ». On ne peut toutefois pas s’en tenir à cette seule lecture. Le principe même de l’allégorie met ici en lumière la proximité foncière de l’ironie et de la poésie, chacune faisant place à une « parole oblique », pour reprendre l’expression de Philippe Hamon. Inscrite, pourrait-on dire, dans le code génétique de la poésie garnélienne, l’ironie est à la source de la révolution copernicienne que la deuxième partie de l’article analysera. En effet, le poème « Autrefois » relate une rupture sur le plan de la conscience poétique ; rupture illustrée notamment par l’usage discordant d’un vocabulaire scientifique. L’ironie intervient ainsi à la faveur d’un retournement critique qui dissipe les illusions provoquées par les premiers enthousiasmes poétiques, dont celle de la centralité du sujet dans le monde. Destinée à devenir un exercice de subtilité, la poésie en mode ironique refuse les excès du lyrisme, qu’ils soient euphoriques ou désespérés, mais cherche l’« équilibre impondérable » qui rallie les contraires : la gravité, le rire ; l’identité, l’altérité ; la poésie, la prose ; l’intelligible, le sensible ; l’apprentissage, le désapprentissage.
Study of Head Scatter Factor in 4 MV Photon Beam Used in Radiotherapy
Authors: Appasamy Murugan , Xavier Sidonia Valas , Kuppusamy Thayalan , Velayudham Ramasubramanian
Published: January 2013

The 4 MV photon beam offers equal build-up region behavior like Co-60 beam and it plays a major role in head and neck and pediatric radiotherapy. In this study an attempt is made to study the head scatter factor (SC) for 4 MV photon beam using locally designed PMMA and Brass miniphantoms. The SC is measured in combination of PMMA miniphantom with 0.6 cc chamber and Brass miniphantom with 0.6 cc and 0.13 cc chambers. The measured SC is compared with the literature data and it agrees within ±1.98%. The study reveals that either 0.13 cc or 0.6 cc chamber with PMMA or Brass phantom materials can be used for SC measurements in a 4 MV photon beam. The variation of SSD does not alter the head scatter factor. The collimator exchange effect is found to be within 1, and it is less than that of other linear accelerators. It is also found that the presence of internal wedge has significant contribution to head scatter factor. The Phantom scatter factor is also calculated and it agrees within ±1% with published data.
A Comparative Evaluation of Ultrasound Molecular Imaging, Perfusion Imaging, and Volume Measurements in Evaluating Response to Therapy in Patient-Derived Xenografts
Authors: Streeter J. E. , Herrera-Loeza S. G. , Neel N. F. , Yeh J. J. , Dayton P. A.
Published: January 2013

Most pre-clinical therapy studies use the change in tumor volume as a measure for disease response. However, tumor size measurements alone may not reflect early changes in tumor physiology that occur as a response to treatment. Ultrasonic molecular imaging (USMI) and Dynamic Contrast Enhanced-Perfusion Imaging (DCE-PI) with ultrasound are two attractive alternatives to tumor volume measurements. Since these techniques can provide information prior to the appearance of gross phenotypic changes, it has been proposed that USMI and DCE-PI could be used to characterize response to treatment earlier than traditional methods. This study evaluated the ability of tumor volume measurements, DCE-PI, and USMI to characterize response to therapy in two different types of patient-derived xenografts (known responders and known non-responders). For both responders and non-responders, 7 animals received a dose of 30 mg/kg of MLN8237, an investigational aurora-A kinase inhibitor, for 14 days or a vehicle control. Volumetric USMI (target integrin: αvβ3) and DCE-PI were performed on day 0, day 2, day 7, and day 14 in the same animals. For USMI, day 2 was the earliest point at which there was a statistical difference between the untreated and treated populations in the responder cohort (Untreated: 1.20 ± 0.53 vs. Treated: 0.49 ± 0.40; p < 0.05). In contrast, statistically significant differences between the untreated and treated populations as detected using DCE-PI were not observed until day 14 (Untreated: 0.94 ± 0.23 vs. Treated: 1.31 ± 0.22; p < 0.05). Volume measurements alone suggested no statistical differences between treated and untreated populations at any read-point. Monitoring volumetric changes is the “gold standard” for evaluating treatment in preclinical studies, however, our data suggests that volumetric USMI and DCE-PI may be used to earlier classify and robustly characterize tumor response.
Individual Beam Sharpening Improves Composite Dose Fall-off near a Target for Non-Isocentric Cyberknife Radiosurgery
Authors: Wahl Michael , Hwang Andrew , Nakamura Jean , Barani Igor , Fogh Shannon , Sneed Penny , McDermott Michael , Sahgal Arjun , Ma Lijun
Published: January 2013

Stereotactic radiosurgery (SRS) refers to a high dose of radiation delivered to a focal region of interest while maximizing the steep dose gradient to minimize dose to the surrounding normal tissues. Multiple factors can influence the dose fall-off, and the relative importance of such factors have not yet been characterized for non-isocentric Cyberknife SRS. Our aim was to investigate whether the composite dose fall-off near a target may be enhanced via sharpening the lateral beam profile (or penumbra) of each individual beam. Cyberknife beam profiles were fitted and parameterized to obtain a characteristic penumbra function for each collimator size. Simulated beam profiles with progressively sharper penumbras were then generated, and used to perform simulated treatment planning on seven pediatric intracranial arteriovenous malformations (AVMs) cases. Penumbra size was found to significantly influence the peripheral dose fall-off. Peripheral dose volumes were reduced by 5 to 10% with reductions in penumbra size ranging from 40 to 80%. Dose conformality and homogeneity were not significantly changed with decreasing penumbra size. Therefore, individual beam sharpening provides a straightforward way of improving the composite dose fall-off for non-isocentric Cyberknife SRS.
Einfach‐, Doppel‐, Dreifachbindungen und Ketten: Knüpfung elektronenpräziser B‐B‐Bindungen
Authors: Braunschweig Holger , Dewhurst Rian D.
Published: January 2013

Trotz des großen präparativen Interesses an Diboranen und der hohen B‐B‐Bindungsenthalpie ist die Knüpfung von Bor‐Bor‐Bindungen immer noch schwierig, kaum zu kontrollieren und schlecht vorhersagbar. Methoden zur Herstellung von B‐B‐Mehrfachbindungen sind sogar noch seltener. In den letzten Jahren gab es nun einige Fortschritte zur Lösung dieser Probleme, und dieser Kurzaufsatz unternimmt den Versuch, einen Überblick über die Geschichte der B‐B‐Bindungsbildung zu geben und neue Ergebnisse auf diesem Gebiet zusammenzufassen.
Synthesis and catalytic activity of the thermoresponsive polymers having pyrrolidine side chains as base functionalities
Authors: Uemukai Toru , Ishifune Manabu
Published: January 2013

Optically active polymers having chiral 2‐aminomethylpyrrolidine side chains have been newly synthesized by a radical homopolymerization of the corresponding protected acrylamide monomer and copolymerization with N‐isopropylacrylamide followed by deprotection. The resulting polymers were found to be thermoresponsive showing lower critical solution temperatures (LCSTs) at 27–65°C in their aqueous solutions. The pyrrolidine side chains of the resulting thermoresponsive polymer promoted aldol reaction between cyclohexanone and p‐nitrobenzaldehyde in water, and the reaction proceeded most smoothly at its LCST. Moreover, the diastereomeric ratio (syn : anti) of the aldol adducts obtained at the reaction at 40°C was 22 : 78, whereas the diastereomeric ratio (syn : anti) was 55 : 45 at 20°C. These results indicate that the pyrrolidine side chains catalyze the aldol reactions in the relatively hydrophobic field generated by the thermoresponsive polymer at its LCST. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Improvement of gas barrier property of polyolefins by diamond‐like carbon deposition and photografting polymerization
Authors: Takahashi Jun , Nakaya Masaki , Matsui Eitaro , Hotta Atsushi
Published: January 2013

The gas barrier properties of isotactic polypropylene (iPP) and high‐density polyethylene (HDPE) are both significantly improved by diamond‐like carbon (DLC) deposition and photografting polymerization using acrylic acid (AA) monomers. In fact, the gas barrier properties can be highly improved just by DLC or by AA‐photografting polymerization. The improvement observed by AA‐photografting polymerization is more pronounced than that by DLC deposition in our general experimental condition. In more detail, the oxygen barrier property of DLC‐deposited and AA‐grafted iPP is considerably improved by ∼10 times when compared with that of neat iPP. As for HDPE, the oxygen barrier property is enhanced by nearly six times through DLC deposition and photografting polymerization. By observing the surfaces, 30 nm layer of DLC and 1.0 μm of AA‐grafted layer are firmly constructed on the polyolefins, which should contribute to the enhancement of the oxygen barrier property. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
The effect of devulcanization level on mechanical properties of reclaimed rubber by thermal‐mechanical shearing devulcanization
Authors: Tao Guoliang , He Qianhu , Xia Yanping , Jia Guangcheng , Yang Haicun , Ma Wenzhong
Published: January 2013

Ground tire rubber (GTR) with crosslinked structure has hardly any plasticity and processability, which makes its property very poor. Thermal‐mechanical shearing devulcanization method can effectively destroy the crosslinked structure and restore GTR a certain extent of plasticity and processability. This article investigated the characteristic and reprocessing performance of reclaimed rubber prepared through thermal‐mechanical shearing devulcanization. The relationship between the devulcanization level (indicated by gel fraction and crosslink density) and the mechanical property was analyzed by sufficient experiments. Fourier transform infrared spectroscopy and elemental analyzer studies revealed the chemical structure of GTR changed and many complex reactions occurred after devulcanization. The gel permeation chromatography indicated the specific changes of molecular weight and molecular weight distribution in devulcanization process. The differential scanning calorimetry revealed various vulcanized abilities and vulcanized structures of reclaimed rubber. The scanning electron microscope further confirmed the recovery of plasticity after devulcanization and the distinct vulcanized structures between revulcanizates. The determination of devulcanization level and mechanical properties verified that mechanical properties especially tensile strength reached to the optimum value only at an appropriate devulcanization level. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Single nucleotide polymorphisms found in the red alga Furcellaria lumbricalis (Gigartinales): new markers for population and conservation genetic analyses
Authors: Olsson Sanna , Korpelainen Helena
Published: January 2013

Expressed sequence tag (EST) libraries were generated from two populations of the red alga Furcellaria lumbricalis (Hudson) Lamouroux originating from different environmental conditions (the Atlantic Ocean and the brackish Baltic Sea), compared with each other and used to guide the design of single nucleotide polymorphism (SNP) markers. The species is endemic to the northern Atlantic, while in the low‐salinity conditions of the Baltic Sea it occurs at the margin of its distribution and is presently threatened by eutrophication.

Primers were developed for 13 transcribed regions, five of which were found to be variable at population level, containing a total of 20 SNP sites, which were then utilized in population genetic analyses on F. lumbricalis originating from different geographical locations and salinity conditions in northern and western Europe, and the results were compared with previous data of putatively neutral and adaptive (EST‐derived) microsatellites.

Although no conclusive evidence of selection was detected in neutrality tests, the level of genetic differentiation based on SNP variation (FST = 0.522; but 0.398 and 0.095 for EST‐derived and putatively neutral microsatellites, respectively) is so great that the role of selection is evident. The Bayesian structure analysis supported the view of great differentiation between marine and brackish populations.

Although the new primers were designed for F. lumbricalis, the same gene regions may have utility in population genetic and phylogenetic studies across red algal species.

Copyright © 2013 John Wiley & Sons, Ltd.
Ligand Functionalization and Its Effect on CO2 Adsorption in Microporous Metal–Organic Frameworks
Authors: Liu Hui , Zhao Yonggang , Zhang Zhijuan , Nijem Nour , Chabal Yves J. , Peng Xiangfang , Zeng Heping , Li Jing
Published: January 2013

We report two new 3D structures, [Zn3(bpdc)3(2,2′‐dmbpy)] (DMF)x(H2O)y (1) and [Zn3(bpdc)3(3,3′‐dmbpy)]⋅(DMF)4(H2O)0.5 (2), by methyl functionalization of the pillar ligand in [Zn3(bpdc)3(bpy)] (DMF)4⋅(H2O) (3) (bpdc=biphenyl‐4,4′‐dicarboxylic acid; z,z′‐dmbpy=z,z′‐dimethyl‐4,4′‐bipyridine; bpy=4,4′‐bipyridine). Single‐crystal X‐ray diffraction analysis indicates that 2 is isostructural to 3, and the power X‐ray diffraction (PXRD) study shows a very similar framework of 1 to 2 and 3. Both 1 and 2 are 3D porous structures made of Zn3(COO)6 secondary building units (SBUs) and 2,2′‐ or 3,3′‐dmbpy as pillar ligand. Thermogravimetric analysis (TGA) and PXRD studies reveal high thermal and water stability for both compounds. Gas‐adsorption studies show that the reduction of surface area and pore volume by introducing a methyl group to the bpy ligand leads to a decrease in H2 uptake for both compounds. However, CO2 adsorption experiments with 1′ (guest‐free 1) indicate significant enhancement in CO2 uptake, whereas for 2′ (guest‐free 2) the adsorbed amount is decreased. These results suggest that there are two opposing and competitive effects brought on by methyl functionalization: the enhancement due to increased isosteric heats of CO2 adsorption (Qst), and the detraction due to the reduction of surface area and pore volume. For 1′, the enhancement effect dominates, which leads to a significantly higher uptake of CO2 than its parent compound 3′ (guest‐free 3). For 2′, the detraction effect predominates, thereby resulting in reduced CO2 uptake relative to its parent structure 3′. IR and Raman spectroscopic studies also present evidence for strong interaction between CO2 and methyl‐functionalized π moieties. Furthermore, all compounds exhibit high separation capability for CO2 over other small gases including CH4, CO, N2, and O2.
Robust Observer and Observer‐Based Controller for Time‐Delay Singular Systems
Authors: Hassan L. , Zemouche A. , Boutayeb M.
Published: January 2013

In this paper we address the problems of observer and observer‐based controller design for a class of nonlinear time‐delay singular systems. The proposed methods use particular Lyapunov functions depending on the disturbances in order to avoid a specific obstacle in the stability analysis. Consequently, two linear matrix inequality (LMI) conditions ensuring the convergence of the estimation error and the closed loop system were presented. These LMIs were obtained by manipulating Young's inequality in order to linearize some bilinear terms.
A comparison of the anticancer properties of isoxanthohumol and 8‐prenylnaringenin using in vitro models of colon cancer
Authors: Allsopp Philip , Possemiers Sam , Campbell David , Gill Chris , Rowland Ian
Published: January 2013

The hops plant (Humulus lupulus L.) is an essential ingredient in beer and contains a number of potentially bioactive prenylflavonoids, the predominant being the weakly estrogenic isoxanthohumol (Ix), which can be converted to the more strongly estrogenic 8‐PN by the colonic microbiota. The aim of this study was to investigate the biological activity of 8‐PN and Ix using in vitro models representing key stages of colorectal carcinogenesis, namely cell growth and viability (MTT assay), cell‐cycle progression (DNA content assay), DNA damage (Comet assay), and invasion (Matrigel assay). A significant decrease in Caco‐2 cell viability was noted after both 8‐PN and Ix treatments at the higher doses (40 and 50 μM, respectively) although the impact on cell cycle differed between the two compounds. The decreased cell viability observed after Ix treatment was associated with a concentration‐dependent increase in G2/M and an increased sub‐G1 cell‐cycle fraction, whereas treatment with 8‐PN was associated with an elevated G0/G1 and an increased sub‐G1 cell‐cycle fraction. Significant antigenotoxic activity was noted at all 8‐PN concentrations tested (5–40 μM). Although significant antigenotoxic activity was also noted with Ix treatment at ≤25 μM, at a higher dose, Ix itself exerted genotoxic activity. In a dose‐dependent manner, both compounds inhibited HT115 cell invasion with reductions up to 52 and 46% for Ix and 8‐PN, respectively, in comparison to untreated cells. This study demonstrated that both Ix and its gut microbial metabolite 8‐PN exert anticancer effects on models of key stages of colon tumourigenesis. © 2013 BioFactors, 39(4):441–447, 2013
DMT1 as a candidate for non‐transferrin‐bound iron uptake in the peripheral nervous system
Authors: Vivot Rocio Martínez , Goitia Belén , Usach Vanina , Setton‐Avruj Patricia C.
Published: January 2013

Iron, either in its chelated form or as holotransferrin (hTf), prevents the dedifferentiation of Schwann cells (SC), cells responsible for the myelination of the peripheral nervous system (PNS). This dedifferentiation is promoted by serum deprivation through cAMP release, PKA activation, and CREB phosphorylation. Since iron elicits its effect in a transferrin (Tf)‐free environment, in this work we postulate that non‐transferrin‐bound iron (NTBI) uptake must be involved. Divalent metal transporter 1(DMT1) has been widely described in literature as a key player in iron metabolism, but never before in the PNS context. The presence of DMT1 was demonstrated in nerve homogenate, isolated adult‐rat myelin, and cultured SC by Western Blot (WB) analysis and confirmed through its colocalization with S‐100β (SC marker) by immunocytochemical and immunohistochemical analyses. Furthermore, the existence of its mRNA was verified in sciatic nerve homogenate by RT‐PCR and throughout SC maturational stages. Finally, we describe DMT1′s subcellular location in the plasma membrane by confocal microscopy of SC and WB of different subcellular fractions. These data allow us to suggest the participation of DMT1 as part of a Tf independent iron uptake mechanism in SC and lead us to postulate a crucial role for iron in SC maturation and, as a consequence, in PNS myelination. © 2013 BioFactors, 39(4):476–484, 2013
Attenuation of glucose transport across Caco‐2 cell monolayers by a polyphenol‐rich herbal extract: Interactions with SGLT1 and GLUT2 transporters
Authors: Farrell Tracy L. , Ellam Samantha L. , Forrelli Taryn , Williamson Gary
Published: January 2013

Previous studies have indicated that secondary plant metabolites may modulate glucose absorption in the small intestine. We have characterized a polyphenol‐rich herbal extract and its potential intestinal metabolites by LC‐MS2 and investigated the inhibition of glucose transporters SGLT1 and GLUT2 using the well‐characterized Caco‐2 intestinal model. Differentiated Caco‐2 monolayers were incubated with an extract of a mixture of herbs and spices. Glucose transport under sodium‐dependent and sodium‐free conditions was determined by radiochemical detection of D−[U‐14C]‐glucose. A 54% decrease in transport was observed compared to control. Using sodium‐dependent and sodium‐free conditions, we demonstrate that the inhibition of GLUT2 was greater than SGLT1. Glycosidase and esterase enzymatic hydrolysis was used to assess the impact of metabolism on the efficacy of inhibition. Glucose transport across the membrane was reduced by 70% compared to the control and was associated with significant increases in flavonoid aglycones, caffeic acid, and p‐coumaric acid. These results suggest that intact and hydrolyzed polyphenols, likely to be found in the lumen after ingestion of the supplement, play an important role in the attenuation of glucose absorption and may have potentially beneficial antiglycemic effects in the body. © 2013 BioFactors, 39(4):448–456, 2013