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CD81 is a member of the tetraspanin family that has been described to have a key role in cell migration of tumor and immune cells. To unravel the mechanisms of CD81-regulated cell migration, we performed proteomic analyses that revealed an interaction of the tetraspanin C-terminal domain with the small GTPase Rac. Direct interaction was confirmed biochemically. Moreover, microscopy cross-correlation analysis demonstrated the in situ integration of both molecules into the same molecular complex. Pull-down experiments revealed that CD81-Rac interaction was direct and independent of Rac activation status. Knockdown of CD81 resulted in enhanced protrusion rate, altered focal adhesion formation, and decreased cell migration, correlating with increased active Rac. Reexpression of wild-type CD81, but not its truncated form lacking the C-terminal cytoplasmic domain, rescued these effects. The phenotype of CD81 knockdown cells was mimicked by treatment with a soluble peptide with the C-terminal sequence of the tetraspanin. Our data show that the interaction of Rac with the C-terminal cytoplasmic domain of CD81 is a novel regulatory mechanism of the GTPase activity turnover. Furthermore, they provide a novel mechanism for tetraspanin-dependent regulation of cell motility and open new avenues for tetraspanin-targeted reagents by the use of cell-permeable peptides. © 2013 Jo et al., PI080794 and PI11/01645 from the Instituto de Salud Carlos III; SAF2011-25834 and ERC AdG-2011; BIO2009-07990 from the Ministerio de Educación y Ciencia; CAM BIO/0194/2006 from Comunidad de Madrid, and RECAVA RD06/0014 from the Fondo de Investigaciones Sanitarias (Ministerio de Sanidad y Consumo, Instituto Salud Carlos III); National Institutes of Health grant GM23244 and the Cell Migration Consortium (U54 GM064346)

In recent decades, we have seen the emergence of private higher education in many European countries. This has been associated with the waves of significant expansion of the higher education system and with changes in regulation patterns, which have promoted a growing private-like behavior of public higher education institutions and the development of private provision in several European countries. The aim of this text is to discuss the relevance of the various dimensions of privatization in European higher education and to explore the relationship between public and private sectors in several European countries. This analysis points out some major patterns of the private higher education sector in Europe and reflects about the major issues faced by those systems regarding the potential contribution of private higher education.

We adopt a process-based approach to investigate the influence of entrepreneurial bosses on the two main decisions of employees towards becoming entrepreneurs: exit from the current firm and entry into entrepreneurship. In other words, we study the push and pull mechanisms possibly underlying the influence of entrepreneurial bosses. We do so by employing an identification strategy based on comparisons of same-gender matches of bosses and employees, using rich register data for Denmark. We show that same-gender entrepreneurial bosses have a great impact on employees' future entrepreneurship choices, especially among women. We do not find any evidence that female bosses push female employees out of the workplace, by creating a discriminatory environment that forces them to search for alternative career paths. Instead, our analysis finds consistent support for pull mechanisms, with role modeling being the main explanation for the positive influence of female entrepreneurial bosses on female employees' transition into entrepreneurship. We show that the female boss effect is greater than other social interactions identified in prior research. We conclude that entrepreneurial bosses can be role models and female entrepreneurial bosses may thus act as a lever to reducing gender gaps in entrepreneurship rates.

Syntenin-1 is recruited to the human immunodeficiency virus (HIV)-induced capping area but vanishes once the viral particles have entered the cell. Syntenin-1 limits HIV-1 infection. Moreover, syntenin-1 depletion specifically increases the HIV-1 entry step without affecting viral attachment to the cell surface. Silencing of syntenin-1 expression blocks actin polymerization triggered by HIV-1 contact and enhances phosphatidylinositol 4,5-bisphosphate production., Syntenin-1 is a cytosolic adaptor protein involved in several cellular processes requiring polarization. Human immunodeficiency virus type 1 (HIV-1) attachment to target CD4+ T-cells induces polarization of the viral receptor and coreceptor, CD4/CXCR4, and cellular structures toward the virus contact area, and triggers local actin polymerization and phosphatidylinositol 4,5-bisphosphate (PIP2) production, which are needed for successful HIV infection. We show that syntenin-1 is recruited to the plasma membrane during HIV-1 attachment and associates with CD4, the main HIV-1 receptor. Syntenin-1 overexpression inhibits HIV-1 production and HIV-mediated cell fusion, while syntenin depletion specifically increases HIV-1 entry. Down-regulation of syntenin-1 expression reduces F-actin polymerization in response to HIV-1. Moreover, HIV-induced PIP2 accumulation is increased in syntenin-1–depleted cells. Once the virus has entered the target cell, syntenin-1 polarization toward the viral nucleocapsid is lost, suggesting a spatiotemporal regulatory role of syntenin-1 in actin remodeling, PIP2 production, and the dynamics of HIV-1 entry.

The expansion of higher education systems has often been associated with the need for increasing diversification, namely at the program level, based on the pressures to adapt more general programmes to a more diverse student population and multiple regional, social, and economic needs. This paper explores empirically the question of programme diversity by drawing on the Portuguese higher education’ experience, which presented massive expansion during the last decades and significant institutional competition in recent years. The study provides a longitudinal approach and analyzes in detail the evolution of diversification and specialization of the public and private sectors, as well as the university and polytechnic subsectors. The analysis aims at helping to illustrate the relevance of analysing diversity from an empirical point of view and its contribution to our understanding of the complex relationships between competition and diversity in contemporary higher education.

The persistent increasing duration of unemployment has become an issue during economic crises. Although lay-offs at large firms normally make headlines during crises, we still know little about the potential impact of firm size on adjustment behavior in a crisis. We studied effects of firm size on employment growth during economic slowdowns using a rich microeconomic database for the 1988-2007 period in Portuguese manufacturing industry. The results show that economic downturns affect firm growth negatively. This negative effect is found to be higher for larger firms, both during and immediately following crisis periods. Small and medium-sized enterprises (SMEs) emerge as potential stabilizers in downturn periods. However, larger firms seem to be able to quickly recover from downturn periods. Our results contribute to the scarce literature and to the understanding of the Portuguese case, where many SMEs secure most jobs. These first results may be useful, because SMEs play a determinant role in other European Union economies.

Recent studies comparing lifetime earnings of individuals with and without entrepreneurial experience have chal-lenged the previously stylized fact that entrepreneurship yields lower and riskier ea...

The human capital of the founding team provides a basis for how the organization is designed and structured, and this founding team imprint influences future resource acquisition due to the path de...

We posit that the decisions to enter and persist into self-employed, are shaped by and intertwined with the decision to become parent. By considering how motherhood and fatherhood influence the par...

Attention is a multidimensional construct with variations throughout development. In Brazil, there is a lack of instruments with adequate psychometric characteristics to evaluate such differences. This study analyzed the contributions of different papers that used attention by cancelling test (ACT and AC) to evaluate development of attention in a normative sample of children (n = 722) and its comparison to clinical sample with ADHD (n = 46). An ANOVA was performed to evaluate the effect of age on ACT, demonstrating a significant difference for correct numbers of responses and of errors. An ANOVA was performed in the ACT to compare data of 78 children, which also showed significantly higher scores based on age. The same pattern occurred in the comparison of 46 children with attention deficit and hyperactivity. The results show improvement on attentional performance with age progression, besides the possibility to use these instruments for characterization of groups with and without indicators compatible with ADHD. Keywords: attention; evaluation; development; cognitive abilities; psychometrics La atención es un constructo multidimensional con variaciones a lo largo del desarrollo. En Brasil hay una falta de instrumentos con características de las psicometrías adecuadas para evaluar tales diferencias. Este estudio analizó las contribuciones de diferentes estudios que utilizaron las pruebas de cancelación de atención (TAC y AC) para evaluar el desarrollo de la atención en una muestra normativa de niños (n = 722) y su comparación con la muestra clínica con TDAH (n = 46). Anova se realizó para evaluar el efecto de la edad en el TAC, demonstrando una diferencia significativa para número de los aciertos y errores. En el teste AC se realizó una Anova de los datos de 78 niños, apuntando también puntuaciones significativamente más altas en base a la edad. El mismo patrón se produjo en la comparación con 46 niños con falta de atención e hiperactividad. Los resultados muestran un mejor rendimiento en la atención con la progresión de la edad y la oportunidad de utilizar estos instrumentos para la caracterización de grupos con y sin indicadores compatibles con TDAH. Palabras clave: atención; evaluación; desarrollo; habilidades cognitivas; psicometría. A atenção é um construto multidimensional com variações ao longo do desenvolvimento. No Brasil, há carência de instrumentos com características psicométricas adequadas para avaliar tais diferenças. Este trabalho analisou contribuições de diferentes estudos que utilizaram testes de atenção por cancelamento (TAC e AC) para avaliação do desenvolvimento da atenção em uma amostra normativa de crianças (n = 722) e sua comparação em amostra clínica com TDAH (n = 46). Foi realizada uma Anova para avaliar o efeito de idade no TAC, demonstrando diferença significativa para número de acertos e erros. No teste AC, realizou-se uma Anova dos dados de 78 crianças que também apontou aumento significativo de acertos em função da idade. O mesmo padrão ocorreu na comparação com 46 crianças com desatenção e hiperatividade. Os resultados mostram melhor desempenho atencional com a progressão da idade, além da possibilidade de uso desses instrumentos para caracterização de grupos com e sem indicadores compatíveis com TDAH. Palavras-chave: atenção; avaliação; desenvolvimento; habilidades cognitivas; psicometria.

This paper studies three related questions: To what extent otherwise similar startups employ different quantities and qualities of human capital at the moment of entry? How persistent are initial human capital choices over time? And how does deviating from human capital benchmarks influence firm survival? The analysis is based on a matched employer-employee dataset and covers about 17,500 startups in manufacturing and services. We adopt a new procedure to estimate individual benchmarks for the quantity and quality of initial human resources, acknowledging correlations between hiring decisions, founders' human capital, and the ownership structure of startups (solo entrepreneurs versus entrepreneurial teams). We then study the survival implications of exogenous deviations from these benchmarks, based on spline models for survival data. Our results indicate that (especially negative) deviations from the benchmark can be substantial, are persistent over time, and hinder the survival of firms. The implications may, however, vary according to the sector and the ownership structure at entry. Given the stickiness of initial choices, wrong human capital decisions at entry turn out to be a close to irreversible matter with significant survival penalties.

Although previous research shows that spin-offs are among the most successful firms in an industry, outperforming de novo entrants, few studies consider the heterogeneity of corporate spin-offs in relation to firm performance or survival. Against this backdrop, the objective of the present chapter is twofold. First, this study aims to add to our knowledge on the relationship between spin-off type and firm survival using a comprehensive matched employer-employee dataset from Portugal. After controlling for their different start-up conditions—namely regarding initial hiring schemes, business-owners’ characteristics, and the industrial and geographical relatedness to the parent firm—and a set of firm, industry, and macroeconomic characteristics, we found no significant survival differences between opportunity and necessity spin-offs. Second, based on the findings, we suggest that necessity spin-offs have not received the attention they deserve. Not only do necessity spin-offs perform an important role in the dynamics of competitive markets, by offering a possible solution for recently displaced individuals, but they also create new jobs and help to prevent the depreciation of workers’ human capital.

The most frequent type of Charcot–Marie–Tooth (CMT) neuropathy is that associated with the 17p11.2–p12 chromosome duplication, whose characteristics have been well described in European and North American populations. In this study, we analyzed a Brazilian population exhibiting the mutation, found in 57 patients from 42 families (79%) of a cohort of 53 families with demyelinating CMT. Almost 20% of the duplicated cases were sporadic. In 77% of the duplicated families the mutation event occurred in the hot spot area of the CMT1A–Rep region. Forty–five percent of patients were females, 84% were Caucasians and 13% of African descent. Distal limb weakness was the most frequent abnormality, appearing in 84% of patients, although uncommon manifestations such as severe proximal weakness, floppy baby syndrome, diaphragmatic weakness and severe scoliosis were also observed. One patient was wheelchair–bound, and three suffered severe hand weakness. Sensory abnormalities were detected in 84% of the cases, but 80% were unaware of this impairment. Twelve patients complained of positive sensory manifestations such as pain and paresthesias. Progression was reported by 40%. Motor conduction velocities in the upper limbs were always less than 35 m/s, and less than 30.4 m/s in the peroneal nerve. The findings of this study expand the clinical spectrum of the disease.

We adopt a process-based approach to investigate the influence of entrepreneurial bosses on the two main decisions of employees towards becoming entrepreneurs: exit from the current firm and entry into entrepreneurship. In other words, we study the push and pull mechanisms possibly underlying the influence of entrepreneurial bosses. We do so by employing an identification strategy based on comparisons of same-gender matches of bosses and employees, using rich register data for Denmark. We show that same-gender entrepreneurial bosses have a great impact on employees’ future entrepreneurship choices, especially among women. We do not find any evidence that female bosses push female employees out of the workplace, by creating a discriminatory environment that forces them to search for alternative career paths. Instead, our analysis finds consistent support for pull mechanisms, with role modeling being the main explanation for the positive influence of female entrepreneurial bosses on female employees’ transition into entrepreneurship. We show that the female boss effect is greater than other social interactions identified in prior research. We conclude that entrepreneurial bosses can be role models and female entrepreneurial bosses may thus act as a lever to reducing gender gaps in entrepreneurship rates.

Mitochondrial respiratory chain (MRC) disorders, defined as primary diseases of the oxidative phosphorylation system, are a protean group of metabolic disorders, difficult to diagnose and classify. The diagnosis is complex and requires the integration of information obtained by clinical, laboratory testing, imaging and muscle biopsy. They may be associated with endocrine disorders, including hypothyroidism, diabetes mellitus, hyperinsulinemia and growth hormone (GH) deficiency.: We describe a case of five years old male with polymalformative syndrome with a systemic involvement. At 6 months of age, he was sent to metabolic consultation because of facial dysmorphy and short stature. During the investigation it was diagnosed at the boy a growth hormone deficiency and because of his multisystemic involvement, muscle biopsy was carried out and showed reduced activity of complex II (38%) of the mitochondrial respiratory chain. Currently, the boy is under GH therapy with growth in the 5th percentile and coenzime Q10.: Mitochondrial biology is one of the fastest growing areas in genetics and medicine. Disturbances in mitochondrial metabolism are now known to play a role not only in rare childhood diseases, but also in many common diseases of aging. In mitochondrial disorders, short stature is a common symptom, but its underlying lesion, growth hormone deficiency, is rarely investigated.

In many cell types, nuclear A-type lamins regulate multiple cellular functions, including higher-order genome organization, DNA replication and repair, gene transcription, and signal transduction; however, their role in specialized immune cells remains largely unexplored. We showed that the abundance of A-type lamins was almost negligible in resting naïve T lymphocytes, but was increased upon activation of the T cell receptor (TCR). The increase in lamin-A was an early event that accelerated formation of the immunological synapse between T cells and antigen-presenting cells. Polymerization of F-actin in T cells is a critical step for immunological synapse formation, and lamin-A interacted with the linker of nucleoskeleton and cytoskeleton (LINC) complex to promote F-actin polymerization. We also showed that lamin-A expression accelerated TCR clustering and led to enhanced downstream signaling, including extracellular signal-regulated kinase 1/2 (ERK1/2) signaling, as well as increased target gene expression. Pharmacological inhibition of the ERK pathway reduced lamin-A-dependent T cell activation. Moreover, mice lacking lamin-A in immune cells exhibited impaired T cell responses in vivo. These findings underscore the importance of A-type lamins for TCR activation and identify lamin-A as a previously unappreciated regulator of the immune response. Spanish Ministerio de Economia y Competitividad (MINECO) [SAF2011-25834, SAF2010-16044]; Comunidad de Madrid [INDISNET-S2011/BMD-2332]; Instituto de Salud Carlos III (ISCIII) [RD12/0042/0028, RD12/0042/0056, CP11/00145]; Progeria Research Foundation [PRF 2012-42]; European Commission [ERC-2011AdG 294340-GENTRIS, 317916-Liphos]; Sara Borrell ISCIII program [CP11/00145]; Miguel Servet ISCIII program [CP11/00145]; Fundacion Mario Losantos del Campo; Fundacion Ferrer para la Investigacion; Obra Social Cajastur; Spanish MINECO; Pro-CNIC Foundation Sí

1. Entrepreneurship And Post-Entry Performance: The Microeconomic Evidence 2. Gibrat's Law, Firms' Growth (and decline) and the Evolution of Firms' Size Distribution 3. Firm Size Distribution and Returns to Scale. Non-Parametric Frontier Estimates from Italian Manufacturing 4. Innovation, growth and survival of Spanish manufacturing firms 5. Survival of the Fittest: Productivity versus Corruption Effects 6. Innovation and Exports of German Business Services Enterprises: First Evidence from a New Type of Firm Data 7. Young, Small and Export Oriented: the Moroccan Winners? 8. Financial fragility and the distribution of firm growth rates: A Quantile Regressions Approach 9. Determinants of Entry and Exit: Evidence from Tunisian Manufacturing Industries 10. Foreign Direct Investment and Firm Survival in Transition Countries 11. Foreign Ownership, Survival and Growth Dynamics in Turkish Manufacturing 12. Foreign investment and firm selection in Italy: the role of linkages and absorptive capacity 13. Global Activities and Plant Survival - The Case of Sweden 14. Firm Survival and Employment Dynamics during Crises 15. What have We Learned? Lessons for Enterprise Policy

For the first time, data on individual European higher education institutions (rather than data aggregated at the country level) is used in order to examine a wide range of issues that are both theoretically challenging and relevant from policy-making and societal perspectives. The contributors integrate statistics on universities and colleges with other sources of information such as patents, start-up firms and bibliometric data, and employ rigorous empirical methods to address a range of key questions, including: what is the role of non-university tertiary education, such as vocational training? How important is the private sector? Are European universities internationalized? Are they efficient from the point of view of costs and educational output? Are there pure research universities in Europe? How do universities contribute to economic growth?

Decades of expansion in European higher education have led to the need to cater to an increasingly diverse student population in a more economical and efficient way. The realities of mass higher education have resulted in major transformations, with visible changes in the modes and instruments of regulation and a greater emphasis on market forces and institutional competition. In this article we reflect about the relevance of those changes from a regional point of view, especially by looking at the public–private mix of higher education and the way those regulatory changes may have influenced patterns of spatial and programmatic diversification across a sample of European countries.

Financial stringency has been an increasing concern in the higher education sector, especially in the aftermath of the financial crisis. As a result, public higher education institutions have been under increasing pressure to diversify their funding sources through tuition fees and other nonpublic revenues. This article reflects on the institutional impact of those changes by analyzing a panel of 30 higher education institutions from the Portuguese public university and polytechnic sectors for the period between 2003 and 2009. The authors explore the relevance of institutional characteristics such as enrollments in undergraduate and postgraduate programs, the qualifications of academic staff, and the regional environment where institutions are located. Results suggest that certain institutional characteristics related to mission differentiation and the path of development of binary systems are important determinants of higher education institutions’ ability to earn income from tuition fees and other nonpublic sources.

Understanding how the immune response is activated and amplified requires detailed knowledge of the stages in the formation of the immunological synapse (IS) between T lymphocytes and antigen-presenting cells (APCs). We show that tetraspanins CD9 and CD151 congregate at the T-cell side of the IS. Silencing of CD9 or CD151 blunts the IL-2 secretion and expression of the activation marker CD69 by APC-conjugated T lymphocytes, but does not affect the accumulation of CD3 or actin to the IS, or the translocation of the microtubule-organizing center toward the T-B contact area. CD9 or CD151 silencing diminishes the relocalization of α4β1 integrin to the IS and reduces the accumulation of high-affinity β1 integrins at the cell-cell contact. These changes are accompanied by diminished phosphorylation of the integrin downstream targets FAK and ERK1/2. Our results suggest that CD9 and CD151 support integrin-mediated signaling at the IS.

HIV-1 contact with target cells triggers F-actin rearrangements that are essential for several steps of the viral cycle. Successful HIV entry into CD4+ T cells requires actin reorganization induced by the interaction of the cellular receptor/co-receptor complex CD4/CXCR4 with the viral envelope complex gp120/gp41 (Env). In this report, we analyze the role of the actin modulator drebrin in HIV-1 viral infection and cell to cell fusion. We show that drebrin associates with CXCR4 before and during HIV infection. Drebrin is actively recruited toward cell-virus and Env-driven cell to cell contacts. After viral internalization, drebrin clustering is retained in a fraction of the internalized particles. Through a combination of RNAi-based inhibition of endogenous drebrin and GFP-tagged expression of wild-type and mutant forms, we establish drebrin as a negative regulator of HIV entry and HIV-mediated cell fusion. Down-regulation of drebrin expression promotes HIV-1 entry, decreases F-actin polymerization, and enhances profilin local accumulation in response to HIV-1. These data underscore the negative role of drebrin in HIV infection by modulating viral entry, mainly through the control of actin cytoskeleton polymerization in response to HIV-1. Background: Drebrin binds to F-actin and CXCR4 in T cells. Thus, it is a potential candidate for the modulation of HIV-1 infection. Results: Drebrin and CXCR4 accumulate at viral attachment areas. Drebrin knockdown decreases F-actin polymerization, and increases local profilin accumulation and HIV-1 infection. Conclusion: Drebrin inhibits HIV-1 entry by stabilizing HIV-1-triggered F-actin polymerization. Significance: Modulation of actin dynamics differentially regulates each viral step for an effective viral infection.

It remains a question whether serial entrepreneurs typically perform better than their novice counterparts owing to learning by doing e¤ects or mostly because they are a selected sample of higher-than-average ability entrepreneurs. This paper tries to unravel these two effects by exploring a novel empirical strategy based on continuous time duration models with selection. We use a large longitudinal matched employer-employee dataset that allows us to track almost 220,000 individuals who have left their first entrepreneurial experience. Over 35,000 serial entrepreneurs are identified and followed in their second business, in order to evaluate how entrepreneurial experience acquired in the previous business improves persistence by reducing their exit rates. Our results show that serial entrepreneurs are not a random selection of ex-business-owners. The positive association found between prior experience and serial entrepreneurs' survival is mainly due to selection on ability, rather than the result of learning by doing.

Selective attention directs cognitive resources to relevant objects or events through either voluntary (top-down) or automatic (bottom-up) control. This paper analyzes voluntary and automatic orienting of attention during childhood development. Seventy-four children (6 to 10 years old) were asked to press a key in response to a visual target presented in a previously oriented position (voluntary orienting; Experiment 1) or after a peripheral unpredictable cue (automatic orienting; Experiment 2). A systematic reduction of reaction times was observed in older children in both experiments. For automatic orienting in Experiment 2, reaction times were shorter in the ipsilateral condition than in the contralateral condition. However, for older children, the differences in reaction times between these conditions decreased. This may be attributable to the appearance of Inhibition of Return as a result of the maturation of the attentional system derived from childhood development, which contributes to more effective exploration of the environment.

This paper conducts a comprehensive study on entrepreneurship dynamics using a large longitudinal matched employer-employee dataset. We identify the transition of over 200,000 nascent business-owners and follow their survival patterns in the respective businesses using discrete time competing risks models. Different profiles of new business-owners are identified, taking into account their entry routes and how such entry choices impact on their persistence in the firm. Exits by dissolution are distinguished from exits by ownership transfer. We also analyze how previous labor market experiences and macroeconomic environment shape the individuals' decision to become and persist as business-owners. Controlling for a set of individual and previous job characteristics, we found that those experiencing a recent displacement are more likely to become entrepreneurs and to persist longer in the business. Concerning macroeconomic conditions, nascent entrepreneurs entering via start-up enter counter-cyclically, while all other nascent business-owners behave in line with the "prosperity-pull" hypothesis. Business-owners' entry choices significantly affect their post-entry persistence and exit modes. Particular experiences in the labor market while paid employees are also found to significantly influence the way individuals enter into and exit from entrepreneurship.

Tetraspanin-enriched microdomains (TEMs) are specialized platforms in the plasma membrane that include certain adhesion receptors, mainly integrins and receptors of the Ig superfamily. Insertion into TEMs increases the local concentration of these adhesion receptors, facilitating their function as avidity regulators. TEMs also regulate interaction and crosstalk between different receptors at the plasma membrane, as well as their internalization rate. Moreover, certain signaling pathways are regulated by association with tetraspanins. Thus, tetraspanins emerge as critical regulators of biological phenomena involving adhesion to the extracellular matrix or homotypic or heterotypic intercellular interactions. These proteins are implicated in different steps of cancer progression, the regulation of intercellular adhesion between polarized epithelial cells, angiogenesis, antigen presentation and extravasation of leukocytes or tumor cells. In addition, several pathogens hijack these tetraspanin-adhesion platforms to increase their infectivity.

The development of mass higher education and growing competition between higher education institutions has given increasing visibility to the issue of diversification. This paper analyses the issue of program diversification using a panel of 181 Portuguese higher education institutions over the period 1995-2007 by comparing the behavior of public and private institutions. The institutional diversity found within the Portuguese higher education system and its evolution over the recent decades provides a suitable and interesting case to perform this analysis. The results show that the legal status of institutions is a major factor regarding diversification, as private institutions are far more specialized than their public counterparts. The study also evaluates which the role of other institutional variables such assize, age, location, category, and research intensity to explain differences in the diversification behavior of higher education institutions. The results provide important insights, as competition has been thought to improve the performance of higher education institutions.

Lactente de 3 meses, com o diagnóstico neonatal de Trissomia 21, deu entrada no serviço de urgência com obstrução nasal e tosse produtiva com quatro dias de evolução. Sem febre. Ao exame objectivo apresentava razoável estado geral, tórax em quilha, obstrução nasal marcada, tiragem global, saturações de O2 de 98% em ar ambiente e frequência respiratória de 40 ciclos/minuto. À auscultação pulmonar apresentava murmúrio vesicular simétrico com raras crepitações bilaterais dispersas. A radiografia do tórax (Figura 1) revelou herniação de vísceras ocas para a cavidade torácica (setas). A tomografia computorizada tóraco-abdominal (Figura 2) confirmou a presença de hérnia diafragmática anterior com presença intra-torácica de cólon. A hérnia de Morgagni é rara, representando apenas 2% dos defeitos diafragmáticos congénitos. Ainda mais rara, é a sua associação com a trissomia 21. A apresentação clínica é variável, desde assintomática a dificuldade respiratória grave, podendo manifestar-se desde o período neonatal à idade adulta. O doente foi submetido a correcção cirúrgica da hérnia diafragmática, com sucesso., Portuguese Journal of Pediatrics, Vol 43 No 3 (2012)

In a context of financial stringency like that characterizing the current economic land-scape in Portugal and in several other countries, accountability and efficiency questions gain an additional relevance in the higher education sector. In this paper we apply DEA techniques to evaluate the comparative efficiency of public higher education institutions in Portugal. The analysis is performed for three separate groups: public universities, public polytechnics and the several faculties of University of Porto. By using several inputs and outputs at the institutional-level, we are able to identify the most technically efficient institutions that may work as benchmark in the sector. The results suggest that a great portion of institutions may be working inefficiently, contributing to a significant waste of resources. This exploratory study is a first step towards a deeper understanding of the efficiency deter-minants of higher education institutions.

EWI motif-containing protein 2 (EWI-2) is a member of the Ig superfamily that links tetraspanin-enriched microdomains to the actin cytoskeleton. We found that EWI-2 colocalizes with CD3 and CD81 at the central supramolecular activation cluster of the T cell immune synapse. Silencing of the endogenous expression or overexpression of a cytoplasmic truncated mutant of EWI-2 in T cells increases IL-2 secretion upon Ag stimulation. Mass spectrometry experiments of pull-downs with the C-term intracellular domain of EWI-2 revealed the specific association of EWI-2 with the actin-binding protein α-actinin; this association was regulated by PIP2. α-Actinin regulates the immune synapse formation and is required for efficient T cell activation. We extended these observations to virological synapses induced by HIV and found that silencing of either EWI-2 or α-actinin-4 increased cell infectivity. Our data suggest that the EWI-2–α-actinin complex is involved in the regulation of the actin cytoskeleton at T cell immune and virological synapses, providing a link between membrane microdomains and the formation of polarized membrane structures involved in T cell recognition.

In recent years we have observed significant growth in the private sector in many higher education systems around the globe. This growth of private higher education is associated with high political expectations, notably concerning greater choice of programs and greater responsiveness of institutions to students' and labor markets' demands. Looking at the experience of several European and Latin American countries, this study analyzes the patterns of program diversification of public and private higher education and discusses the impact of the private sector for the diversification of higher education's supply. The results show a contrasting picture between political beliefs about privatization in higher education and its actual results, suggesting that private institutions tend to be far more specialized than their public counterparts.

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CD81 is a tetraspanin protein that is involved in several essential cellular functions, as well as in the hepatitis C virus (HCV) infection. CD81 interacts with a high stoichiometry with its partner proteins EWI-2, EWI-2wint, and EWI-F. These latter proteins modify the functions of CD81 and can thereby potentially inhibit infection or modulate cell migration. Here, we characterized the cleavage of EWI-2 leading to the production of EWI-2wint, which has been shown to inhibit HCV infection. We determined the regions of EWI-2/EWI-2wint and CD81 that are important for their interaction and their functionality. More precisely, we identified a glycine zipper motif in the transmembrane domain of EWI-2/EWI-2wint that is essential for the interaction with CD81. In addition, we found that palmitoylation on two juxtamembranous cysteines in the cytosolic tail of EWI-2/EWI-2wint is required for their interaction with CD81 as well as with CD9, another tetraspanin. Thus, we have shown that palmitoylation of a tetraspanin partner protein can influence the interaction with a tetraspanin. We therefore propose that palmitoylation not only of tetraspanins, but also of their partner proteins is important in regulating the composition of complexes in tetraspanin networks. Finally, we identified the regions in CD81 that are necessary for its functionality in HCV entry and we demonstrated that EWI-2wint needs to interact with CD81 to exert its inhibitory effect on HCV infection.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Attention can be understood as a group of neural processes that allow an adequate selection of information from the environment, in this way orienting adaptive responses. Thus, its study is made necessary so that cognitive processes and how their alterations express themselves through adaptive difficulties can be comprehended, such as it is observed in cases of Attention Deficit Disorder and/or Hyperactivity (ADDH). This study aims at performing a neuropsychological and behavioral evaluation, centered in the analysis of the attentional process of 78 junior high children, enrolled in a private school, with ages between 6 and 11. Traditional manuscript tests and computer-based tests were employed for the evaluation of attention. The instruments used were: WISC-III; Wisconsin; Focused Attention (AC and TECON) and Diffuse Attention (TEDIF) In behavioral evaluation the Behavioral Scale (CBCL/6-18), applied to parents, was used. For the teachers, the Signs of Disattention and Hyperactivity Scale (Benzic) was employed, along with the Behavioral Scale (TRF). The computer-based tests evaluated the voluntary and automatic orientation, temporal direction an attention management. The results from the computer-based instruments were compared to the results from the traditional pencil and paper tests, along with the behavioral and the Signs of Disattention and Hyperactivity scales. No indicators of behavioral problems were observed, and there was no report from either parents (CBCL) or teachers (TRF) on that matter. The results of the traditional tests related to Focused Attention (FC, TECON-1 and TECON-2, TEDIF 1 and TEDIF-3) showed significantly higher scores and points related to schooling. The computer-based tests, on the other hand, showed a systematic lowering of the reaction time related to the increase in schooling. However, as schooling increases, there is a decrease in the differences between the valid and the invalid conditions, making participants more efficient in perceiving stimuli outside the indicated location. Another factor that presented significant difference was the Clue Target relation factor, in which it is possible to observe that the reaction time for the condition in which the target and the clue come from the same side (ipsolateral condition) is lower than the reaction time for the condition in which the target and the clue come from opposite sides (contralateral condition). With the Wisconsin test is possible to verify that with the increase in schooling there is a decrease in the number of tests administered and also an increase in the number of categories completed, as well as a decrease on the total amount of errors and the number of preservative answers, and that this fact correlates with the decrease in the reaction time in computer-based tests, demonstrating that the skills that were evaluated by each one of this tests are also correlated. A atenção pode ser compreendida enquanto conjunto de processos neurais que possibilitam a seleção adequada de informações do ambiente e que por isso orientam respostas adaptativas. Desse modo, seu estudo é necessário para a compreensão dos processos cognitivos e de como suas alterações se expressam por dificuldades adaptativas, tais como as observadas em casos de Transtorno de Déficit de Atenção e/ou Hiperatividade (TDAH). O objetivo deste estudo foi o de fazer uma avaliação neuropsicológica e comportamental centrada na análise do processo atencional de 78 crianças do Ensino Fundamental I, matriculadas em uma escola particular e com idade entre 6 e 11 anos. Foram empregados testes tradicionais de realização em lápis e papel e testes computadorizados para avaliação da atenção. Os instrumentos utilizados foram: WISC-III; Wisconsin; Atenção Concentrada (AC e TECON) e Atenção Difusa (TEDIF). Na avaliação comportamental foi utilizada a Escala Comportamental (CBCL/6 18) aplicada aos pais. Para os professores foram empregadas a Escala de Sinais de Desatenção e Hiperatividade (Benczik), além de Escala Comportamental (TRF). Os testes computadorizados avaliaram a orientação voluntária e automática, o direcionamento temporal e a manutenção da atenção. Foram comparados os resultados dos instrumentos computadorizados com os resultados dos testes tradicionais de respostas em lápis e papel e com as escalas comportamentais e de sinais de desatenção e hiperatividade. Não foram observados nos participantes indicadores de problemas de comportamento relato dos pais (CBCL) ou pelos professores (TRF). Os resultados dos testes tradicionais relacionados à Atenção Concentrada (AC, TECON-1 e TECON -2, TEDIF-1 e TEDIF-3) demonstram aumento significativo de acertos e pontos em função da escolaridade. Já nos testes computadorizados houve uma diminuição sistemática do tempo de reação em função do aumento da escolaridade. Entretanto, à medida que a escolaridade aumenta há uma diminuição das diferenças entre a condição válida e inválida, tornando os participantes mais eficientes em perceber estímulos fora dos locais indicados. Outro fator que apresentou diferença significativa foi quanto ao tempo de reação para a condição aonde pista alvo vêm na mesma posição (condição ipsolateral) é menor do que o tempo de reação para a condição na qual a pista e o alvo vêm em lados opostos (condição contralateral). No teste Wisconsin é possível verificar que com o aumento da escolaridade há uma diminuição no número de ensaios administrados e também um aumento de número de categorias completadas bem como diminuição no total de erros e de número de respostas perseverativas, e que tal fato se correlaciona com a diminuição do tempo de reação nos testes computadorizados, demonstrando que as habilidades avaliadas por cada um desses testes também estão correlacionadas.

The global crisis has called to further reflection on the role of multinationals in host economies during crisis. The evidence on this matter is scarce and no definite conclusions were achieved. Using panel data analysis, this paper examines the link between foreign ownership, firm employment and turnover growth over 20 years and during economic downturns in particular. We analyse the determinants of firm employment and turnover growth and investigate whether there are significant differences in both variables among domestic and foreign firms when controlling for firm and industry specificities. Additionally we assess if the foreignness effect alters during economic downturns. After controlling for several firm and industry characteristics, we find no significant differences between domestic and foreign firms in what concerns employment growth. However, our results suggest that foreign ownership may affect positively firms’ sales turnover growth during recessions.

Background Three percent of the world's population is chronically infected with hepatitis C virus (HCV) and thus at risk of developing liver cancer. Although precise mechanisms regulating HCV entry into hepatic cells are still unknown, several cell surface proteins have been identified as entry factors for this virus. Among these molecules, the tetraspanin CD81 is essential for HCV entry. Interestingly, CD81 is also required for Plasmodium infection. A major characteristic of tetraspanins is their ability to interact with each other and other transmembrane proteins to build tetraspanin-enriched microdomains (TEM). Results In our study, we describe a human hepatoma Huh-7 cell clone (Huh-7w7) which has lost CD81 expression and can be infected by HCV when human CD81 (hCD81) or mouse CD81 (mCD81) is ectopically expressed. We took advantage of these permissive cells expressing mCD81 and the previously described MT81/MT81w mAbs to analyze the role of TEM-associated CD81 in HCV infection. Importantly, MT81w antibody, which only recognizes TEM-associated mCD81, did not strongly affect HCV infection. Furthermore, cholesterol depletion, which inhibits HCV infection and reduces total cell surface expression of CD81, did not affect TEM-associated CD81 levels. In addition, sphingomyelinase treatment, which also reduces HCV infection and cell surface expression of total CD81, raised TEM-associated CD81 levels. Conclusion In contrast to Plasmodium infection, our data show that association of CD81 with TEM is not essential for the early steps of HCV life cycle, indicating that these two pathogens, while using the same molecules, invade their host by different mechanisms.

In order to develop an efficient large-scale extraction of secologanin from Symphoricarpos albus, different methods have been compared. Ultrasonication with organic solvents and water, microwave-assisted extraction and hot water extraction methods were evaluated for their efficiencies. Among the methods tested, ultrasonication with methanol showed the highest yield of secologanin (3.35 ± 0.24 mg/g fresh weight). For reliable quantification of secologanin a 1H-NMR method was developed. The experiment was performed by the analysis of the integral of the signal of H-9, which was well separated in the range δ 7.4–7.5 in the 1H-NMR spectrum. The quantity of the compound was calculated from the relative ratio of intensity of the target peak to the known amount of internal standard, 200 µg of gallic acid. This method allows rapid and simple quantification of secologanin in 5 min without any pre-purification steps. Copyright © 2004 John Wiley & Sons, Ltd.

Two to three percent of the world's population is chronically infected with hepatitis C virus (HCV) and thus at risk of developing liver cancer. Although precise mechanisms regulating HCV entry into hepatic cells are still unknown, several cell surface proteins have been identified as entry factors for this virus. Among these molecules, the tetraspanin CD81 is essential for HCV entry. Here, we have identified a partner of CD81, EWI-2wint, which is expressed in several cell lines but not in hepatocytes. Ectopic expression of EWI-2wint in a hepatoma cell line susceptible to HCV infection blocked viral entry by inhibiting the interaction between the HCV envelope glycoproteins and CD81. This finding suggests that, in addition to the presence of specific entry factors in the hepatocytes, the lack of a specific inhibitor can contribute to the hepatotropism of HCV. This is the first example of a pathogen gaining entry into host cells that lack a specific inhibitory factor.

For the first time, data on individual European higher education institutions (rather than data aggregated at the country level) is used in order to examine a wide range of issues that are both theoretically challenging and relevant from policy-making and societal perspectives. The contributors integrate statistics on universities and colleges with other sources of information such as patents, start-up firms and bibliometric data, and employ rigorous empirical methods to address a range of key questions, including: what is the role of non-university tertiary education, such as vocational training? How important is the private sector? Are European universities internationalized? Are they efficient from the point of view of costs and educational output? Are there pure research universities in Europe? How do universities contribute to economic growth?

The actin cytoskeleton plays a key role during the replication cycle of human immunodeficiency virus-1 (HIV-1). HIV-1 infection is affected by cellular proteins that influence the clustering of viral receptors or the subcortical actin cytoskeleton. Several of these actin-adaptor proteins are controlled by the second messenger phosphatidylinositol 4,5-biphosphate (PIP2), an important regulator of actin organization. PIP2 production is induced by HIV-1 attachment and facilitates viral infection. However, the importance of PIP2 in regulating cytoskeletal proteins and thus HIV-1 infection has been overlooked. This review examines recent reports describing the roles played by actin-adaptor proteins during HIV-1 infection of CD4+ T cells, highlighting the influence of the signaling lipid PIP2 in this process.