bluuebunny/crossref_metadata_2025 huggingface dataset:
LETRAMENTO MATEMÁTICO Y DESEMPEÑO ESTUDIANTIL EN ENEM-BRASIL
Authors: Da Silva e Neto Jhemerson , Santos Wádila Caroline da Silva , Ripardo Ronaldo Barros , Sousa Silva José Fábio
Published: August 2022

En Brasil, se han realizado evaluaciones a gran escala con el propósito de medir los niveles de competencia matemática de los estudiantes, como el Exame Nacional do Ensino Médio (Enem), además de utilizarlo como prueba de selección para la admisión de estudiantes para cursos de pregrado. Consideramos lo letramento matemático como una matemática que se desarrolla a partir de las prácticas sociales de lectura y escritura en el ámbito de los conceptos matemáticos, es decir, un uso para una comprensión más amplia del mundo, más allá de la decodificación de códigos numéricos y geométricos, etc. El objetivo de este artículo es analizar el dominio de las habilidades de letramento matemático de los estudiantes que terminan la escuela secundaria en función de su desempeño en la prueba de matemáticas del Enem. Como supuesto metodológico, la presente investigación sigue el método de investigación mixto. El marco temporal de los datos comprende el período de 2013 a 2017 y el período geográfico a la Mesorregión Sur y Sudeste del Estado de Pará em Brasil. Los resultados muestran que el porcentaje promedio de respuestas correctas es 21 y que en el ranking de las ocho primeras Las competencias con menores índices de éxito se centran en los Ejes III y V, respectivamente, afrontando situaciones problemáticas y elaborando propuestas de intervención en la realidad.
ANÁLISIS DE LA PRODUCCIÓN CIENTÍFICA BRASILEÑA SOBRE ALFABETIZACIÓN CIENTÍFICA COMO ACCIÓN PEDAGÓGICA EN LOS PRIMEROS AÑOS DE LA ESCUELA PRIMARIA
Authors: Sobrinho Elizimari de Queiroz , Leão Marcelo Franco
Published: August 2022

O presente estudo teve como objetivo compreender o tratamento dado aos conteúdos no desenvolvimento de ações pedagógicas da Alfabetização Científica (AC) para estudantes dos anos iniciais do Ensino Fundamental conforme as publicações em periódicos nacionais, na última década. Metodologicamente, esta pesquisa se configura como básica, exploratória, de abordagem qualitativa, bibliográfica, do tipo estado do conhecimento. Ademais, o estudo considerou como recorte temporal a última década, devido ser um período de transição entre documentos norteadores da prática educativa. Optou-se, também, pelos repositórios Periódicos CAPES e o SciELO como banco de dados e fontes de informações. Das 82 produções científicas encontradas sobre AC nos anos iniciais do Ensino Fundamental, selecionou-se 10 artigos que tinham caráter prático, ou seja, que envolviam estudantes desta etapa da escolarização. Além do mais, foram pré-estabelecidos os seguintes critérios de análises: Conceituação do objeto; Autores basilares; Abordagem ou menção aos documentos educacionais norteadores; Ação metodológica; Tratamento dado ao conteúdo. Ressalta-se que foi possível identificar que as sequências didáticas se mostraram recorrentes para desenvolver conteúdos com foco na construção de habilidades que são constituintes da Alfabetização Científica. Logo, foi possível conhecer mais de uma visão por parte dos teóricos sobre a definição de AC e notar que as concepções variam entre a vertente da linguagem, do domínio de conceitos, de termos e da formação crítica.
TAC y Estrategias de Enseñanza para Favorecer la Permanencia y Terminalidad en Educación Superior
Authors: Mallo Adriana , Bertazzi Graciela
Published: August 2022

Las universidades nacionales argentinas son gratuitas y de libre acceso, lo que produce masividad en el ingreso. Sin embargo, a pesar de la cantidad de estudiantes que ingresan, las altas tasas de deserción y el bajo índice de egreso son datos alarmantes (Secretaría de Políticas Universitarias del Ministerio de Educación de la Nación Argentina).  En este contexto, las instituciones universitarias enfrentan el desafío de adecuar sus prácticas y metodologías para producir aprendizajes significativos y, así, favorecer la permanencia y terminalidad de los estudiantes. Para ello, la educación debería enfocarse en la formación de los estudiantes como seres autónomos, responsables y críticos (Delgadillo, Valderrama & Guachetá, 2006), con un rol activo en relación a su propio aprendizaje y comprometidos en el proceso; estudiantes capaces de analizar y resolver problemas de diferentes índoles, de asumir responsabilidades sociales, con competencias y aptitudes para la buena comunicación, el análisis creativo, el pensamiento independiente y la habilidad para el trabajo en equipo. Para formar un estudiante con estas competencias, existen modelos pedagógicos emergentes que, junto con las tecnologías del aprendizaje y el conocimiento (TAC), permitirían viabilizar las trasformaciones que la educación requiere en la actualidad, disminuir las tasas de deserción de los estudiantes y motivarlos a finalizar sus estudios. Se pueden mencionar, entre esos modelos, la Clase Invertida, el Aprendizaje Basado en Proyecto, la Gamificación, el Pensamiento de Diseño. En cuanto a las TAC se cuenta, hoy, con variadas y creativas herramientas que posibilitan la implementación de estos modelos. Asimismo, se necesita un cambio en el rol docente, quien debería poseer no sólo capacidad reflexiva y una actitud crítica, sino también utilizar las TAC y las estrategias de enseñanza adecuadas y convertirse en acompañante del proceso de aprendizaje del estudiante. El objetivo del presente trabajo es analizar las estrategias pedagógicas más apropiadas para lograr este cometido. Es decir, qué replanteos deberían hacer los docentes para que las clases, en la universidad, estimulen a los estudiantes para que finalicen, en tiempo y forma, sus carreras y adquieran las destrezas y competencias necesarias para desempeñarse con éxito como profesionales.
UJI CEMARAN MIKROBA DAN AKTIVITAS ANTIBAKTERI EKSTRAK BAWANG PUTIH TUNGGAL TERHADAP BAKTERI GRAM NEGATIF
Authors: Suriawati Junie , Siti Rahayu Rachmawati
Published: August 2022

Bawang putih (Allium sativum L) merupakan salah satu tanaman obat yang sudah dikenal sejak lama. Bawang putih mengandung senyawa aktif yaitu senyawa organosulfur diantaranya allicin (diallyl disulfide) dan ajoene (dially thiosulfinate) yang berperan sebagai antibakteri. Ekstrak bawang putih digunakan sebagai sediaan farmasi dan makanan, sehingga harus memenuhi syarat cemaran mikroba. Tujuan penelitian untuk mengetahui jumlah cemaran mikroba dan aktivitas antibakteri ekstrak bawang putih terhadap bakteri Gram negatif (Escherichia coli). Sampel penelitian ini adalah bawang putih tunggal yang sebelumnya sudah dideterminasi di “Herbarium Bogoriense”, Direktorat Pengelolaan Koleksi Ilmiah BRIN Cibinong. Kontaminasi mikroba ekstrak bawang putih dideteksi dengan angka lempeng total (ALT) dan angka kapang khamir (AKK). Uji aktivitas antibakteri menggunakan metode difusi sumur dengan konsentrasi ekstrak 25%, 50%, 75%, 100%, serta diulang sebanyak tiga kali. Diperoleh hasil uji ALT sebesar 1,05 x 102 CFU/mL dan AKK sebesar 1 x 101 CFU/mL. Ekstrak bawang putih dapat membentuk zona hambat pada konsentrasi 25%, 50%, 75% dan 100% masing-masing 14,7 mm, 17,7 mm, 19,0 mm dan 20,0 mm. Semakin besar konsentrasi nilai zona hambat semakin besar. Kesimpulan ekstrak bawang putih telah memenuhi persyaratan sesuai dengan standar jumlah cemaran mikroba yaitu ALT ? 105 CFU/mL dan AKK ? 103 CFU/mL serta aman digunakan sebagai bahan baku. Aktivitas antibakteri ekstrak bawang putih menunjukkan efek antibakteri terhadap Escherichia coli.
Penetration Testing and Cyber Security Studies in Bangladesh
Authors: Hossain Shahadat , Rahman Lamiya , Azad Rafat , Hasan Md. Manzurul , Jebin Mehenaj , Mahmud Md. Siam , Sakib Md. Sadman
Published: August 2022

The COVID-19 pandemic and consecutive lockdowns have made people dependent on the online environment and have made society compatible with virtual platforms. But the management of the electronic environment is not so easy but too crucial and vital as well as needs to be user-friendly. As a developing country, Bangladesh has welcomed digital changes. Unfortunately, threats and vulnerabilities have risen in lockstep with technological advancement. To deal with this issue, businesses and educational institutions are turning to cyber security. Penetration testing (Pen-Test) is a way of assessing the security of a web application, system, or network by systematically checking and confirming the efficacy of that system. The purpose, classifications, and uses of penetration testing in Bangladesh's IT industries are discussed in this chapter and depict the present state of cyber security in Bangladesh. The authors highlight some of the aspects that contribute to the country's cyber vulnerabilities. Finally, several proposals are made to protect Bangladesh's cyberspace against harmful assaults.
Compassionate Acts as Missional Theosis: A Call to the Evangelical Church of Southern Africa (ESCA)
Authors: Harold Prof. Dr Godfrey
Published: August 2022

The Church is God's agency to bring about well-being in the world (Harold, 2018a). This
bringing out of well-being to humanity call for an understanding of justice and compassion through a missional reading of the Bible and its intersection with "actions" of the Evangelical Church in post-apartheid South Africa. The aim of this article is two-fold, the first, is to examine the praxis of the Evangelical Church and its relevance to the marginalised in South Africa critically, and the second, is to help the ECSA understand that a missional reading or a missional hermeneutic through theosis brings about a correct understanding (orthodoxy) of compassion, justice and the Missio Dei leading to the right action (orthopraxis). Using literature, this article will explore and recommend ways the ECSA can act prophetically by speaking to and on behalf of the voiceless in South Africa. The researcher then employs the notion of Theosis to show that by acting compassionately, the Church reflects the very nature of God.
KUCHUM KHAN AGAİNST THE RUSSİAN OCCUPATİON OF SİBERİA
Authors: İREVANLI Sevil
Published: August 2022

When examining the Finn branch, one of the five main branches of the Turanians, it is seen that; The Finn branch separated from the Altai steppes in prehistoric times, much earlier than other tribes, by migrating to the north and west. It is seen that the language of the Turanians, their historical data and their current places are considered together; The first Turan people to come into contact with Europe are the Finns. In fact, when we look at the Turkish epics and written documents of the Irtysh River tribes, BC. It is a geography where Turks have lived and settled since ancient times. After the disintegration of the Göktürk Khaganate, of which the Kipchaks were an important element, it is seen that the Kimek clan united in Western Siberia, which was under its dominance, and then spread to the wide steppe area. Senior Siberian researcher M. A. Castren, in a letter he wrote to his friend from Nazımova in 1847, with his own irony; “You can say hi to Runeberg (a Swedish-language Shahname poet in Finland) from me. Consider the Kuchum Khan Empire, which has hitherto been the only Finnish state, as a suitable subject to study. Kuchum Khan himself was a Turk, but his effort in resisting Yermak and the relations of these two heroes are really worth processing in the poem," he wrote. The research results of the Castren era have since been repeatedly censored. Key words: Siberya,Ural-Altai, Kimek-Kipchaks, Kuchun Khan, Russian Attack, Censorhip.
Developing an Electric Mobility Roadmap: International Experiences from Subnational Case Studies for Vietnamese Cities
Authors: Liu Kangjie , Ly Stephanie , Jackson Eleanor , Steimer Hamilton , Cassius Sarah , Li Xiangyi , Myers Erika , Hernandez Duarte Lorenzo , Freehafer Lydia
Published: August 2022

This paper uses subnational case studies to compare city and provincial electric mobility roadmaps and provides preliminary recommendations for Vietnamese cities based on case study observations. In addition, the paper discusses the process of preparing, creating, and implementation an electric mobility roadmap, covering aspects such as prerequisite analyses, stakeholder engagement, supporting policy formulation, and monitoring. Throughout the paper, experiences from actual case studies are referenced and analyzed.
Physiological and metabolic responses of microcystin-producer cyanobacterial strains to inorganic carbon
Authors:   , Oder Jean Coutinho
Published: August 2022

The phylum Cyanobacteria (Bacteria domain) constitutes a group of gram-negative prokaryotes able to perform oxygenic photosynthesis. These organisms are widely distributed around the globe and can be found in free form or in symbiotic associations with plants, diatoms, fungi, and sponges. Cyanobacteria are very important for the biogeochemical cycles of carbon (C) and nitrogen (N), because they are able to fix inorganic C (Ci) and some genera also perform biological N fixation (BNF). Some cyanobacterial strains also produce toxins (cyanotoxins), such as microcystins (MCs), which have hepatotoxic effects in animals. In this study, we evaluated the effects of different Ci sources on the metabolism of two filamentous heterocytous MC-producer strains (Scytonemataceae CCM-UFV057 and Neowestiellopsis sp. CCM-UFV026), characterizing their growth and metabolic responses. For this, the two strains were grown separately in BG-11 0 medium, with 0.02 g·L -1 of sodium carbonate [control (C)]; and in BG-11 0 medium, with 0 g·L -1 (T1), 0.016 g·L -1 (T2), 0.032 g·L -1 (T3), 0.16 g·L -1 (T4), 0.8 g·L -1 (T5) and 1.6 g·L -1 of sodium bicarbonate (T6). The growth parameters of strain Neowestiellopsis sp. CCM-UFV026 were affected at T1 (0.016 g·L -1 of sodium bicarbonate), but were not affected as the Ci concentration increased. The strain Scytonemataceae CCM-UFV057 showed lower growth at T6 (1.6 g·L -1 of sodium bicarbonate). In the highest sodium bicarbonate concentration, both strains showed decreased pigment contents (chlorophyll a and phycobiliproteins). The strain Neowestiellopsis sp. CCM-UFV026 had its metabolism and growth rate less impacted at the higher Ci concentration than the strain Scytonemataceae CCM-UFV057, since the latter showed signs of chlorosis in its culture and high values of cellular glycogen. Keywords: Heterocitous strains. Growth rate. Growth curves. Metabolites contents.
Hipertensão Intra-Abdominal e Síndrome Compartimental Abdominal
Authors: M. Pereira Bruno , K. A. Fiorelli Rossano , Gonçalves Matheus , Biscalquin Helena , Sampaio Nathália , Fracari Yana , Matoba Caio , K. A.Fiorelli Stenio , M. S. Ascenção Agostinho , Rossi Maurício , G. Pereira Renato , R. Almeida Camila , Novellino Pietro
Published: August 2022

A hipertensão intra-abdominal (HIA) e a síndrome compartimental abdominal (SCA) são causas estabelecidas de morbidade e mortalidade em pacientes gravemente enfermos. Quando o interesse na HIA pós-operatória após grandes cirurgias, cirurgias vasculares, trauma e pacientes críticos surgiu na década de 1980, a SCA era a única síndrome clínica reconhecida e a laparotomia descompressiva o único tratamento definitivo. Desde então, elevações menos extremas da pressão intra-abdominal (PIA), definidas como HIA, foram reconhecidas como altamente prevalentes entre todos os tipos de pacientes internados em unidade de terapia intensiva (UTI). Avanços significativos na compreensão da fisiopatologia, diagnóstico e tratamento de HIA e SCA ocorreram nas últimas décadas. A importância da HIA foi estudada especificamente em pacientes críticos, levando a uma melhor compreensão dos mecanismos de disfunção orgânica devido ao aumento da PIA e oportunidades mais precoces de intervenção terapêutica. Além disso, técnicas médicas e minimamente invasivas foram desenvolvidas e relatadas como potencialmente eficazes em pequenos estudos.
MILITARES E PROTESTANTES EM DEFESA DO CAPITALISMO DURANTE A DITADURA MILITAR NO BRASIL
Authors: Souza Rogério Luiz Klaumann de , Silva Thiago Rodrigo da
Published: August 2022

Neste trabalho, buscamos apresentar uma reflexão sobre a ideia da defesa do ocidente capitalista como uma das características comuns aos grupos majoritários das instituições militares e das igrejas protestantes brasileiras.
historia da religiao e das praticas de religiosidade
Authors: Corso João Carlos
Published: August 2022

A percepção de que mesmo com esforço de inúmeros intelectuais em desvendar o campo da História da Religião e das práticas de Religiosidade ainda há muito a se fazer. Desse modo pensamos em contribuir com esse importante debate acadêmico através da publicação de e-book.
Chemical Aspects of the Deep Repository Safety
Authors: Vokál Antonín
Published: August 2022

This review summarises the basic principles of evaluating the safety of the deep geological repository and describes the considered safety and technical concept of the deep geological repository planned in the Czech Republic. This concept is compared with similar concepts planned abroad. The next part of the review focuses on the discussion of chemical processes affecting the safety of the deep geological repository, especially on the degradation of engineered barriers and chemical processes related to the migration of radionuclides into the environment.
Study of Emotional Intelligence and Well-Being among Working Professionals
Authors: Kochhar Megha , Tripathi K N
Published: August 2022

Working professionals’ social and mental capacities are critical to the smooth operation of
organizations. Emotional intelligence (EI) nowadays has become synonymous with mental health,
happiness, and well-being. Looking at the importance of emotional intelligence, the present study
examined the pattern of emotional intelligence and wellbeing with its dimensions of professionals working
as managers in private and government sector banks. It was also investigated whether professional
hierarchy and work tenure produced any significant differences for the aforementioned variables. The
results of the study indicated that professionals working in different sectors, in different cadres, and in
different work tenures indicated significant differences in their perceptions. Similarly, co-relational
analysis results demonstrated that all essential components of well-being (WB) are profoundly,
fundamentally, and decisively linked (p.01) with EI. To be sure, emotion influences how individuals
think and act and influences judgement and information processing. Employees with higher EI can
discover appropriate arrangements all the more easily, work and apply emotional resources sensibly
and can frequently rapidly get social help in correspondence and cooperation with individuals, thereby
lessening the chance of disappointment and the depersonalization achieved by disappointment.
Unravelling the ‘Help’ in Self-Help
Authors: Sharma Radhika , Bharadwaj Ishita U
Published: August 2022

The present article intends to explore the challenges faced by the urban professionals in reaching for the emotional and professional amidst the neoliberal marketplace, via the narratives salient in Self-Help texts. Self-Help texts embody metaphors that rely on agency bound “bootstrapping” narratives, where individuals are compelled to maximise their agency in terms of tangible profits and fulfil their calculated potential in the social marketplace of competition. The neoliberal marketplace obfuscates the existing inequalities through narratives of multiculturalism and individual empowerment. Deliberation through thematic analysis, this article intends to look into the emergence of the ‘achievable self’ through the prevalence of Self Help texts as a popular genre in the Indian scenario. It also seeks to discuss the mental health challenges faced by individuals in meeting the achievement benchmarks of the current ethos, and how Self-Help texts posit themselves as providing the means to do so. The emergent themes will be discussed in the article in detail. This article seeks to explore the relationship between the reader and self-help texts to better understand the process by which newer conceptualisations of mental wellbeing as an achievement benchmark have emerged.
Relationship between Alexithymia, difficulties in emotion regulation, mental health and internet addiction in young adults
Authors: Nahar Riya N , Kakulte Arvind
Published: August 2022

The internet has become a necessary tool for everyone in the 21st century. From using Google, YouTube, Facebook, Instagram to paying bills, shopping, etc. the internet provides us with a range of services. But at the same time, the number of hours spent online mindlessly scrolling through the websites or binge watching your favorite shows has increased and has become a cause of worry – for both, physical and mental health related issues. The present study aimed to investigate the role of certain psychological variables which are associated with addiction, mainly internet addiction. Alexithymia, emotion regulation difficulties and poor mental health can result into problematic internet use among young adults. Based on these views, it was hypothesized that these variables have association with internet addiction and internet addiction can be predicted by them. Total 250 young adults from different parts of the country participated in the study via offline and online modes of data collection following the safety protocols for COVID-19 virus. Consent form, demographic details and variable tests were given to the sample. Data analysis indicated that alexithymia and difficulties in emotion regulation had a positive correlation with internet addiction, mental health had a negative correlation and regression was significant. Out of all the three variables emotion regulation difficulties could explain internet addiction. Results showed that there was an association between alexithymia, difficulties in emotion regulation, mental health and internet addiction (is greater than 0.01 significant level).
Operational evaluation of atomization indicators for gasoline with admixtures of ethanol and butanol during Keep-Clean tests
Authors: Pielecha Ireneusz , Stępień Zbigniew
Published: August 2022

The global policy of reducing road transport sector pollution requires the introduction of significantly modified already in use technologies and construction solutions. Currently, direct fuel injection technology is the best solution in terms of reducing fuel consumption and exhaust emissions of standard pollutants into the atmosphere, as well as further improving the engine performance. In terms of exhaust emissions, direct injection spark ignition engines are characterized by significantly higher exhaust emissions of particulate matter (approximately 10 times higher) compared to indirect fuel injection SI engines, they show a greater tendency to knocking combustion and are prone to the formation of harmful deposits on engine parts, including in the fuel injectors. The injector tips located in the combustion chamber are exposed to the direct influence of the very high pressure and temperature caused by the combusting fuel-air mixture, which contributes to the rapid formation of harmful deposits. Operation-based injectors contamination in spark ignition engines results in a reduction of the cross-sectional flow diameter of the injector, which then necessitates the extension of the injection time in order to maintain the fuel dose and the expected engine operating parameters. The tests were carried out on an engine dynamometer and an optical test stand for fuel atomization process. The presented research analyzes indicate the possibility of using admixtures that effectively reduce the likelihood of contamination. The paper presents a results analysis of engine tests performed in accordance with the CEC F-113-KC procedure. Additionally, the injectors were tested to conduct an analysis of the injected fuel stream’s geometric indicators. The range, surface area and speed of the injected fuel stream as well as the fuel distribution in the stream were determined based on an equivalent indicator. The obtained results indicated that ethanol and butanol admixtures of 10% (V/V) to gasoline did not significantly extend the fuel injection time as compared to the reference fuel. A further increase in the proportion of ethanol caused a significant deterioration of the fuel flow and the geometric indicators of the fuel spray.
Extending the social category label effect to stigmatized groups: Lesbian and gay people’s reactions to “homosexual” as a label
Authors: Matsick Jes L. , Kruk Mary , Palmer Lindsay , Layland Eric K. , Salomaa Anna C.
Published: August 2022

The social category label effect describes how labels influence people’s perceptions of social groups. Though the label “homosexual” versus “lesbian/gay” decreases some heterosexual people’s support for sexual minorities, it is unknown how lesbian and gay (LG) people respond to “homosexual” as a label used to describe them. Across three experiments in a largely U.S. context (Total N = 831), we examined how use of “homosexual” influenced people’s responses on psychological instruments, preferences for demographic questions, and evaluations of individuals who use “homosexual.” The use of different labels in psychological measures did not influence LG people’s responses (Study 1). However, LG people reacted less positively to “homosexual” compared to “lesbian/gay” in demographic questions and in interpersonal exchanges (Studies 2-3), whereas heterosexual people’s reactions were largely unaffected (Study 2). LG people’s more negative reactions to “homosexual” than “lesbian/gay” were partially explained by them perceiving the “homosexual” label user as less culturally competent (i.e., less inclusive, less engaged in LGBTQ activism). In this article, we make progress in new empirical territory (sexual orientation-based cues research), propose the notion of linguistic heterosexism, and discuss the sociopolitical implications of people’s language choices.
Gênero e saúde: uma articulação necessária
Authors: Brandrão Elaine Reis
Published: August 2022

O objetivo das autoras com este livro é gerar reflexão e diálogo – entre pesquisadores/as e estudantes de graduação e pós-graduação das áreas de ciências da saúde, ciências sociais e humanas, profissionais da saúde, gestores públicos, integrantes de instâncias de controle social do SUS e ativistas de movimentos sociais organizados – sobre a importância da compreensão da problemática de gênero como modo de organização da vida social, focando, especialmente, em seu impacto na configuração dos processos de saúde e doença em diversos grupos sociais. Para tanto, apresentam os íntimos entrelaçamentos entre os estudos históricos, sociológicos e antropológicos sobre gênero, os estudos sociais da ciência e tecnologia e o campo da saúde, que foram se consolidando ao longo da segunda metade do século XX até o presente, com implicações teóricas, éticas e políticas que incidem tanto na compreensão dos fenômenos de saúde-doença, nas práticas de atenção à saúde e de cuidados com o corpo, quanto na formulação de políticas públicas de saúde.
Jump risk in the U.S. stock market: Evidence using political information
Authors: Lobo Bento J.
Published: July 2002

We examine the impact of U.S. elections and partisan politics on the stock market using jump–diffusion models of daily stock returns from 1965 to 1996. Our approach permits us to track jump risk in stock markets stemming from political incentives, and to separate the impact of routine trading and informational surprises, or jumps, on the mean and volatility of stock returns in election years and across partisan administrations. Our estimates reveal that the pattern of jumps and of routine trading varies with the political calendar. We find that midterm elections are a more important source of uncertainty compared to presidential elections. Jump risk increases by 10 and 20 percent for small and large‐cap stocks, respectively, in midterm election years. We also find that small stocks perform better under Democrats relative to Republicans. However, unexpected events are more frequent during Democratic administrations and these increase the jump risk, especially for large stocks, in these regimes.
Interaction of protein tyrosine phosphatase (PTP) 1B with its substrates is influenced by two distinct binding domains
Authors: DADKE Shrikrishna , CHERNOFF Jonathan
Published: July 2002

We have shown previously that protein tyrosine phosphatase (PTP) 1B interacts with insulin receptor and negatively regulates insulin signalling by an N-terminal binding domain [Dadke, Kusari and Chernoff (2000) J. Biol. Chem. 275, 23642–23647] and it also negatively regulates integrin signalling through a proline-rich region present in the C-terminus [Liu, Hill and Chernoff (1996) J. Biol. Chem. 271, 31290–31295; Liu, Sells and Chernoff (1998) Curr. Biol. 8, 173–176]. Here we show that PTP1B mutants that are defective in Src homology 3 domain binding fully retain the ability to inhibit insulin signalling, whereas mutants defective in insulin-receptor binding fully retain the ability to inhibit integrin signalling. In contrast, both the C-terminal proline-rich region and the tandem tyrosine residues present in the N-terminal region are required for the activation of Src family kinases. These data show that PTP1B can independently regulate insulin and integrin signals, and that Src might represent a convergence point for regulating signal transduction by this phosphatase.
Supporting pupils in mainstream school with an illness or disability: young people’s views
Authors: Lightfoot J. , Wright S. , Sloper P.
Published: July 2002

To date, little research has focused directly on health‐related support in school for children with a chronic illness or physical disability, yet these children are known to be at increased risk for psychosocial and academic problems. In addition, few studies have sought the views of pupils directly: those which have report a wide range of problems with school life. The increasing numbers of children surviving and managing their health conditions, together with UK policy for inclusive education, means that a growing proportion of pupils in mainstream schools require understanding of their special health needs and may need service support from education and health professionals. This paper presents findings from semistructured interviews with 33 mainstream secondary school pupils with a variety of illnesses and disabilities on the impact of their health condition on school life. Results show that young people valued school and were actively managing the effects of their condition, but needed support from others. Informal support was most frequently cited, including parents — particularly mothers — teachers and close friends. The main difficulties were implications of school absence, exclusion from school life, teachers’ reactions to the illness or disability, and peer relationships. The discussion focuses on ways in which health professionals can play a part in supporting pupils both directly and indirectly, through helping others in school understand the condition and its impact on school life.
Prevalence of muscle relaxant sensitivity in a general population: implications for a preoperative screening
Authors: PORRI F. , LEMIERE C. , BIRNBAUM J. , GUILLOUX L. , LANTEAUME A. , DIDELOT R. , CHARPIN D. , VERVLOET D.
Published: July 2002

Background

Muscle relaxants (MR) are responsible for 59% of peroperative anaphylactic reactions. A major issue would be to determine whether a systematic preoperative screening in the general population should be recommended.

Objective

The purpose of the study was to evaluate the prevalence of muscle relaxant sensitivity in a sample of the general population and to assess the role of possible risk factors.

Methods

Two hundred and fifty‐eight subjects, aged 20–40 years, visiting a health care centre for a check‐up were evaluated. Protocol included a questionnaire (occupation, symptoms of atopy, previous surgery, history of drug allergy), skin‐prick tests to four commercial muscle relaxants and measurement of specific IgE against quaternary ammonium ions. Atopy was evaluated by skin‐prick tests to common inhalant allergens and by a Phadiatop test.

Results

Of the study group, 9.3% had either a positive skin test to one or more muscle relaxant or a presence of specific IgE to quaternary ammonium ions. No risk factor was identified in the studied group.

Conclusion

Since the rate of MR sensitivity is much higher than the anticipated rate of peroperative reactions due to allergy, a systematic preoperative screening for MR allergy should not be recommended for adults in a general population.
Differential Expression and Modulation of Costimulatory Molecules CD80 and CD86 on Monocytes from Patients with Systemic Lupus Erythematosus
Authors: LIU M.‐F. , LI J.‐S. , WENG T.‐H. , LEI H.‐Y.
Published: July 2002

Patients with systemic lupus erythematosus (SLE) were recently shown to be defective in costimulatory molecule CD80 (B7‐1) expression on antigen‐presenting cells. This study was undertaken to further investigate the expression and cytokine regulation of both CD80 and CD86 (B7‐2) on monocytes from patients with SLE. Freshly isolated and in vitro cytokine‐stimulated peripheral blood mononuclear cells from 13 patients with SLE and 10 healthy subjects were analysed, cytometrically with dual‐fluorescence staining, to detect expression of CD80 and CD86 in the CD14+ monocyte population. The results showed that, as in normal individuals, an overwhelming majority (95.62 ± 3.54%) of monocytes from patients with SLE expressed the CD86 molecule, but only a few monocytes (5.54 ± 4.36%) had detectable CD80 expression. The effects of interleukin‐10 (IL‐10) on the expression of CD80 and CD86 on monocytes from patients with SLE and normal controls were similar. IL‐10 down‐regulated the expression of CD86 while it slightly enhanced that of CD80. Interferon‐γ (IFN‐γ) increased both CD80 and CD86 expression on monocytes from both SLE patients and normal groups, albeit less significantly in the former than in the latter, i.e. CD80: 142.84 ± 65.99% versus 226.08 ± 78.90%, P < 0.05; and CD86: 72.55 ± 74.23% versus 153.99 ± 94.14%, P < 0.05, when expressed as percentage modulation. Granulocyte–macrophage colony‐stimulating factor (GM‐CSF) showed a capacity for up‐regulation of CD80 and CD86 expression on monocytes, of a magnitude that was similar both in patients with SLE and in normal subjects. We concluded that CD80 and CD86 were differentially expressed and modulated on monocytes and the defective IFN‐γ‐induced up‐regulation of CD80 and CD86 expression on SLE monocytes might be a factor in the pathogenesis of SLE.
Fertilization and the first cleavage mitosis in insects
Authors: Kawamura Naoko
Published: July 2002

Fertilization in animals is now considered to be of the ‘sea urchin type’; that is, haploid male and female pronuclei completely fuse shortly after sperm entry into the egg, followed by the formation of a mitotic spindle to allow cleavage mitoses to proceed. However, two other patterns of fertilization and early embryonic mitosis in some animal species are known: an Ascaris type and a gonomeric type. The gonomeric type of fertilization in insects and other arthropods is not well known and is quite different from the sea urchin and Ascaris types. In the present article, the author examines the peculiar gonomeric fertilization, using mainly the silkworm as an example.
Healthy Ageing – Adults with Intellectual Disabilities: Summative Report
Authors:   World Health Organization
Published: July 2002

This document has been jointly prepared by International Association for the Scientific Study of Intellectual Disabilities (IASSID) and Inclusion International (II) in collaboration with the Department of Mental Health and Substance Dependence and the Programme on Ageing and Health, World Health Organization, Geneva to which, jointly, all rights are reserved. The document may, however, be freely reviewed, abstracted, reproduced or translated in part, but not for sale or use in conjunction with commercial purposes. It may also be reproduced in full by non‐commercial entities for information or for educational purposes with prior permission from WHO/IASSID/II. The document is likely to be available in other languages also. For more information on this document, please visit the following websites:  and .
High current density in bulk YBa2Cu3Ox superconductor
Authors: Salama K. , Selvamanickam V. , Gao L. , Sun K.
Published: July 2002

A liquid phase processing method for the fabrication of bulk YBa2Cu3Ox superconductors with large current carrying capacity has been developed. Slow cooling through the peritectic transformation (1030–980 °C) has been shown to control the microstructure of these superconductors. A cooling rate of 1 °C/h in this temperature range has yielded a microstructure with long plate type, thick grains oriented over a wide area. Current density up to 18 500 A/cm2 has been obtained by continuous direct current measurements and in excess of 62 000 A/cm2 with pulse current of 10 ms duration and 75 000 A/cm2 using 1 ms pulse. The strong magnetic field dependence observed in sintered bulk 1-2-3 superconductors is also minimized to a large extent where a current density in excess of 37 000 A/cm2 is obtained in a field of 6000 G.
Formation of quasicrystals by mechanical alloying
Authors: Eckert J. , Schultz L. , Urban K.
Published: July 2002

Quasi-crystalline Al65Cu20Mn15 powder has been produced by mechanical alloying from crystalline elemental powders. The alloying process has been monitored by x-ray diffraction, and the resulting product has been characterized by transmission electron microscopy. The quasi-crystalline phase forms after about 90 h of milling. The crystallization temperature and enthalpy have been determined by differential scanning calorimetry. The results are compared with data for melt-spun material.
Bragg confinement of carriers in a quantum barrier
Authors: Lenz Gadi , Salzman Joseph
Published: July 2002

A high band-gap material surrounded by two short-period superlattices of lower band gap is proposed for carrier confinement to the barrier. The combined structure behaves as a Fabry–Perot cavity for carriers as long as coherence of the carrier wave function is maintained. Since Bragg confinement and creation of a mini-gap energy state is sensitive to the value of the carrier effective mass, the system is also an effective mass filter for light holes.
Novel method for determining the electromagnetic dispersion relation of periodic slow wave structures
Authors: Carmel Y. , Guo H. , Lou W. R. , Abe D. , Granatstein V. L. , Destler W. W.
Published: July 2002

A novel method for calculating the dispersion relation of electromagnetic modes in an arbitrary periodic slow wave structure is reported. In this method it is sufficient to know the frequencies corresponding to three special wave number values, with other points calculated using an approximate analytical expression. This technique was successfully applied to determine the dispersion relation of the TM01 mode in a sinusoidally corrugated slow wave structure. This structure is commonly used in relativistic high-power backward wave oscillators and traveling-wave tubes, and is expected to have many additional applications.
Structure of the ZnSe/GaAs heteroepitaxial interface
Authors: Li D. , Gonsalves J. M. , Otsuka N. , Qiu J. , Kobayashi M. , Gunshor R. L.
Published: July 2002

Interfaces of pseudomorphic (100) ZnSe/GaAs heterostructures grown by molecular beam epitaxy have been studied by transmission electron microscopy. The observation of three different heterostructures suggests the existence of a transition structure at the ZnSe/GaAs interfaces which have formed on As-deficient GaAs surfaces. The transition structure appears as a bright line in dark field images of the 200 reflection, while it becomes a dark line in dark field images of the 400 reflection. These observations are explained by assuming the existence of an interface layer which has a zinc blende type structure having vacancies in one of the face centered cubic sublattices.
Optoelectronic generation of time-division multiplexed ultrafast bit stream on a coplanar waveguide
Authors: Shu C. , Zhang X.-C. , Yang E. S. , Auston D. H.
Published: July 2002

We have developed a technique to generate a two-dimensional array of optical beams with equal intensities and a constant sequential time delay from a mode-locked laser. A light modulator was used to code the spatially separated beams, which were then multiplexed to form a serial pulse string. With the multiplexed beam focused on a picosecond photoconductor, an ultrafast electrical signal was generated.
Onset of incoherency and defect introduction in the initial stages of molecular beam epitaxical growth of highly strained InxGa1−xAs on GaAs(100)
Authors: Guha S. , Madhukar A. , Rajkumar K. C.
Published: July 2002

Direct evidence for interplanar relaxation in islands at the initial stages of strained epitaxy is presented using molecular beam epitaxically deposited In0.5Ga0.5As on GaAs(100). Concomitant existence of atomic displacements in the substrates to unexpectedly large depths of ∼150 Å is found. In incoherent islands, defects are found to be introduced symmetrically near the island edges.
Use of high-temperature superconductors for resonators of far-infrared p-germanium lasers
Authors: Bespalov A. V. , Lang P. T. , Betz J. , Renk K. F.
Published: July 2002

We report for the first time on the use of high-temperature superconductor material for fabricating a resonator of a far-infrared solid-state laser. In our experiment the active medium consisted of a p-germanium crystal at 4.2 K in crossed electric and magnetic fields. We used a SrTiO3 plate as highly reflecting mirror and a YBa2Cu3O7−δ thin films on an MgO plate as output coupling mirror. We demonstrate highly reproducible operation of the laser.
Secondary cavitation due to interaction of a collapsing bubble with a rising free surface
Authors: Tomita Y. , Kodama T. , Shima A.
Published: July 2002

An experimental investigation was made of the motion of a cavitation bubble in the vicinity of a free surface in order to study an induced secondary cavitation during the bubble rebound. A bubble was produced by focusing a ruby laser into water, and its subsequent behavior was observed with a high-speed camera. The deformable nature of both a bubble and a free surface becomes significant as the mutual distance between them is decreased. Immediately after bubble rebound, a secondary cavitation occurs at around zero dynamic pressure region which is developed in water between a rising free surface and a collapsing bubble, due to the local pressure reduction mainly caused by the interaction of expansion waves originated from the surface.
Impact-induced failure waves in glass bars and plates
Authors: Brar N. S. , Bless S. J. , Rosenberg Z.
Published: July 2002

Glass bars and plates were subjected to impact loading. Failure waves were observed to propagate behind the compression waves. Material traversed by the failure wave suffers total loss of tensile strength and substantial drop in shear strength. Failure wave propagation velocities exceed the maximum crack propagation speed, but are not constant. In bars, failure wave speed range from 2.3 to 5.2 mm/μs, increasing with increasing impact velocity; in plates, the wave speed is about 2 mm/μs. The failure is ‘‘explosive’’ in nature, leading to radial expansion in bars and an increase in mean stress in plates.
Molecular beam epitaxial growth and characterization of CoAl on AlAs/GaAs
Authors: Tanaka M. , Sakakibara H. , Nishinaga T.
Published: July 2002

We study molecular beam epitaxial growth and structural properties of intermetallic compound CoAl on AlAs/GaAs III-V semiconductors. CoAl has a CsCl structure whose lattice constant is nearly half the lattice constant of GaAs and AlAs, hence, it is a good candidate for the constituent material in epitaxial metal/semiconductor heterostructures. We investigate the dependence of crystallinity of Co1−xAlx epitaxial layers on Al composition x and on growth temperature Ts, by in situ reflection high-energy electron diffraction and ex situ x-ray measurements. It is found that the single-crystalline CoAl with high quality can be obtained at x=0.5 and Ts=350 °C. Under appropriate growth procedures and conditions, the epitaxial growth orientation is (001)[110]CoAl on (001)[110]AlAs/GaAs.
Experimental evidence of Bragg confinement of carriers in a quantum barrier
Authors: Zahler M. , Brener I. , Lenz G. , Salzman J. , Cohen E. , Pfeiffer L.
Published: July 2002

We report the low-temperature photoluminescence and its excitation spectra of GaAs/Al0.32Ga0.68As Bragg confining structures. The spectra of these structures, which consist of short superlattice sections separated by Al0.32Ga0.68As spacer layers, are compared with those of conventional superlattices. The energies of the observed optical transitions between the Bragg confined levels (localization on the spacer layer) are in a good agreement with calculations, based on the Kronig–Penney model for the envelope functions of the electrons and holes.
Quantum pillar structures on n+ gallium arsenide fabricated using ‘‘natural’’ lithography
Authors: Green Mino , Garcia-Parajo M. , Khaleque F. , Murray R.
Published: July 2002

Random arrays of CsCl hemispherically shaped islands with average diameters as small as 500 Å have been made on n+GaAs substrates. The CsCl behaves as a resist of high selectivity when the GaAs is reactively ion etched in a BCl3 plasma. The resulting structure is a set of pillars all the same height, but with varying diameters, typically ±15% of the average value, 〈D〉. Typical pillar packing density, S, is 20%. Photoluminescence (PL) studies were made at 10 K on n+ and semi-insulating GaAs using 514.5 nm exciting radiation. PL spectra from n+GaAs structures of 〈D〉=520±78 Å, h=800 Å, S=20%; 〈D〉=610±97 Å, h=450 Å, S=12%; 〈D〉=1215±210 Å, h=600 Å, S=20%, as well as a plane surface, are reported. There is a shift in the peak value of the PL curves with respect to the planar structure of 26, 13, and 2.5 meV, respectively. It may be possible to understand these shifts in terms of quantum confinement effects if the effective pillar size is reduced by surface space charge effects.
Donor and acceptor concentrations in molecular beam epitaxial GaAs grown at 300 and 400 °C
Authors: Look D. C. , Robinson G. D. , Sizelove J. R. , Stutz C. E.
Published: July 2002

The first Hall-effect measurements on molecular beam epitaxial GaAs layers grown at the low temperatures of 300 and 400 °C are reported. Two independent methods were used to determine donor ND and acceptor NA concentrations and activation energy ED0, with the following combined results: ND≂3±1×1018, NA≂1.5±1×1017 cm−3, and ED0=0.645±0.009 eV for the 300 °C layer; ND≂2±1×1017, NA≂7±3×1016 cm−3, and ED0=0.648±0.003 eV for the 400 °C layer. Thus, the deep donor is not the expected EL2, which has ED0=0.75±0.01 eV.
Observation of impurity effects on the nucleation of arsenic precipitates in GaAs
Authors: Ibbetson J. P. , Speck J. S. , Gossard A. C. , Mishra U. K.
Published: July 2002

The precipitation of arsenic in low temperature GaAs uniformly doped with Si and Be has been studied by transmission electron microscopy. Following an in situ anneal at 600 °C, precipitate size and density is found to be strongly dependent on the dopant type. Impurities at the epilayer/substrate interface lead to heterogeneous nucleation of precipitates. Although precipitates were observed to nucleate heterogeneously at threading dislocations, the precipitates predominantly form homogeneously. These results are consistent with the general theory of precipitation in solids.