The meaning of the h-index

The questions in this article were formulated by G. Buela-Casal, the answers were given by J.E. Hirsch.The h-index originates from the assumption that the number of citations received by a scientist is a better indicator of the relevance of his or her work than the number of papers he or she publishes or the journals where they are published. It takes into account the number of papers published and the citations to those papers in a balanced way, and thus is useful to make comparisons between scientists. The present paper addresses the most frequent questions about the h-index. Specifically, it explains its origin, its advantages compared to other indices, the factors that can influence it (e.g. age, field of knowledge, topic of research and language of publication), its variants, and the injustices it may lead to. In short, this paper provides a clear exposition of the hoped-for role of the h-index in the evaluation of scientists: that it serves as a useful complement to other indicators that are more subjective, and that it contributes to the progress of science by aiding decision-making on allocation of research resources in a more effective way, and on rewarding researchers who contribute to scientific progress in a more fair way.El índice h surge del presupuesto de que el número de citas que recibe un científico constituye un mejor indicador de la relevancia de su trabajo que el número de artículos que publica o en qué revistas lo hace. Se trata de un indicador que, a partir del balance entre el número de publicaciones y las citas a éstas, permite la comparación entre distintos científicos. En este artículo se da respuesta a las preguntas más frecuentes acerca del índice h. En concreto, se describe su origen, cuáles son sus ventajas con respecto a otros índices, los factores que pueden influirle (edad, campo de conocimiento, las propias temáticas de investigación o idioma en que se publica), sus variantes y sus injusticias. En definitiva, se expone de forma clara cuál es la función esperada del índice h en la evaluación de los científicos: que complemente a otros indicadores más subjetivos, y que contribuya en forma positiva al avance de la ciencia al ayudar la toma de decisiones de alocación de recursos para la investigación en forma más efectiva y de recompensar a los que contribuyen al avance científico en forma más ecuánime.Open Access funded by Asociación Española de Psicología Conductua

Integrated electromyogram and eye-gaze tracking cursor control system for computer users with motor disabilities

This research pursued the conceptualization, implementation, and testing of a system that allows for computer cursor control without requiring hand movement. The target user group for this system are individuals who are unable to use their hands because of spinal dysfunction or other afflictions. The system inputs consisted of electromyogram (EMG) signals from muscles in the face and point-of-gaze coordinates produced by an eye-gaze tracking (EGT) system. Each input was processed by an algorithm that produced its own cursor update information. These algorithm outputs were fused to produce an effective and efficient cursor control. Experiments were conducted to compare the performance of EMG/EGT, EGT-only, and mouse cursor controls. The experiments revealed that, although EMG/ EGT control was slower than EGT-only and mouse control, it effectively controlled the cursor without a spatial accuracy limitation and also facilitated a reliable click operation

Structure-function analysis of the curli accessory protein CsgE defines surfaces essential for coordinating amyloid fiber formation

Curli amyloid fibers are produced as part of the extracellular biofilm matrix and are composed primarily of the major structural subunit CsgA. The CsgE chaperone facilitates the secretion of CsgA through CsgG by forming a cap at the base of the nonameric CsgG outer membrane pore. We elucidated a series of finely tuned nonpolar and charge-charge interactions that facilitate the oligomerization of CsgE and its ability to transport unfolded CsgA to CsgG for translocation. CsgE oligomerization in vitro is temperature dependent and is disrupted by mutations in the W48 and F79 residues. Using nuclear magnetic resonance (NMR), we identified two regions of CsgE involved in the CsgE-CsgA interaction: a head comprising a positively charged patch centered around R47 and a stem comprising a negatively charged patch containing E31 and E85. Negatively charged residues in the intrinsically disordered N- and C-terminal “tails” were not implicated in this interaction. Head and stem residues were mutated and interrogated using in vivo measurements of curli production and in vitro amyloid polymerization assays. The R47 head residue of CsgE is required for stabilization of CsgA- and CsgE-mediated curli fiber formation. Mutation of the E31 and E85 stem residues to positively charged side chains decreased CsgE-mediated curli fiber formation but increased CsgE-mediated stabilization of CsgA. No single-amino-acid substitutions in the head, stem, or tail regions affected the ability of CsgE to cap the CsgG pore as determined by a bile salt sensitivity assay. These mechanistic insights into the directed assembly of functional amyloids in extracellular biofilms elucidate possible targets for biofilm-associated bacterial infections.Curli represent a class of functional amyloid fibers produced by Escherichia coli and other Gram-negative bacteria that serve as protein scaffolds in the extracellular biofilm matrix. Despite the lack of sequence conservation among different amyloidogenic proteins, the structural and biophysical properties of functional amyloids such as curli closely resemble those of amyloids associated with several common neurodegenerative diseases. These parallels are underscored by the observation that certain proteins and chemicals can prevent amyloid formation by the major curli subunit CsgA and by alpha-synuclein, the amyloid-forming protein found in Lewy bodies during Parkinson’s disease. CsgA subunits are targeted to the CsgG outer membrane pore by CsgE prior to secretion and assembly into fibers. Here, we use biophysical, biochemical, and genetic approaches to elucidate a mechanistic understanding of CsgE function in curli biogenesis

Implementação BIM ao nível do licenciamento municipal: verificação automatizada do RGEU

O setor da construção civil tem registado um crescente desenvolvimento no que se refere à metodologia ‘Building Information Modelling’ (BIM) e aos seus diversos usos e aplicações. A verificação de regras, no âmbito do Licenciamento de Obras, é uma das vertentes que se encontra em franco desenvolvimento a nível mundial. Neste contexto, o presente artigo que baseia numa dissertação de mestrado desenvolvida na Universidade do Minho, elaborada em colaboração com a Gaiurb EM, aborda a utilização da verificação automatizada de regras com o intuito de entender como esta pode ser implementada pelas Câmaras Municipais. Foi desenvolvido um caso de estudo posteriormente testado para a verificação do cumprimento das regras estabelecidas no Decreto-Lei n.º 220/2008, de 12 de novembro, que define o Regulamento Geral das Edificações Urbanas (RGEU). Para isso, foi necessário classificar as regras previstas no RGEU quanto à possibilidade de serem interpretadas e verificadas através de um software, e posteriormente testar a verificação automatizada através do modelo do caso de estudo, possibilitando compreender os desafios gerados pela verificação automatizada, como a interpretação das regras escolhidas, a sua inserção num software de verificação e as necessidades de informação que o modelo precisa conter para que a verificação ocorra corretamente. Desta forma, foi possível sugerir propostas para a implementação do uso da verificação automatizada de regras para licenciamento, no caso particular do RGEU

Implementation of an Ultraviolet Phototherapy Service at a National Referral Hospital in Western Kenya: Reflections on Challenges and Lessons Learned.

IntroductionIn order to manage skin conditions at a national referral hospital level in Kenya, specialized dermatology services, such as dermatologic surgery, dermatopathology, phototherapy, and sub-specialty care, should be offered, as is typically available in referral hospitals around the world. A Kenyan patient with prurigo nodularis, whose severe itch remitted after phototherapy treatment at the University of California, San Francisco (UCSF), inspired the development of a phototherapy service at Academic Model Providing Access to Healthcare (AMPATH), a partnership in Western Kenya between Moi Teaching and Referral Hospital, Moi University College of Health Sciences, and a consortium of North American academic medical centers.MethodsInitial project funds were raised through a crowdfunding campaign and fundraising events. A new narrowband ultraviolet B phototherapy unit and replacement bulbs were donated and air shipped to Eldoret, Kenya. A team of dermatologists and phototherapy nurses from UCSF conducted a 2-day training session. US-based dermatologists affiliated with AMPATH provide ongoing support through regular communication and on-site visits.ResultsEarly in implementation, challenges faced included training clinical staff with limited experience in phototherapy and improving communication between nurses and clinicians. More recent challenges include frequent rotation of specialty clinic nurses in the dermatology clinic, adaptation of phototherapy guidelines to balance patient volume with service delivery capacity, and training assessment of disease activity in darkly pigmented skin.ConclusionStrategies that have been helpful in addressing implementation challenges include: increasing on-site and remote training opportunities for clinicians and nurses, developing a tiered payment schema, educating patients to combat misconceptions about phototherapy, dynamic phototherapy referral guidelines to accommodate service delivery capacity, and prioritizing the engagement of a multidisciplinary team

Association of falls, fear of falling, handgrip strength and gait speed with frailty levels in the community elderly

Introduction: The Frailty Syndrome is not synonymous with disability, but may be a precursor of etiological and physiological dysfunction, which affects mobility before causing reduced functional capacity, explaining conditions of weakness, weight loss, and abnormal gait. Study design: This is an analytical, observational, cross-sectional study. Objective: To verify the association of handgrip strength, gait speed, fear of falling, and falls with the level of frailty. Methods: Study consisting of 54 participants, aged 65 and older, enrolled in a health care and monitoring government program in the municipality of Uberaba, Minas Gerais, Brazil. The volunteers were assessed for frailty, – non-frail group (NG), pre-frail group (PG), and frail group (FG) – according to the Fried criteria, and based on the outcomes of handgrip strength, gait speed, fear of falling, and falls. An inferential descriptive statistical analysis followed, with Chi-square and KruskallWallis tests performed by the Stata11.0 software. Results: In the comparative analysis between the groups studied there was statistical significance relative to handgrip strength (FG and NG), gait speed (NG and FG / NG and PG), and fear of falling (NG and FG). There was no significant difference between the levels of frailty and falls. Conclusions: Frailty is associated with reduced muscle strength, decreased gait speed, and greater fear of falling in elderly people of the communit

Parameters That Influence the Extent of Site Occupancy by a Candidate Telomere End-binding Protein

The MF3 protein specifically recognizes telomeric and non-telomeric DNA probes that can form G.G base-paired structures (Gualberto, A., Patrick, R. M., and Walsh, K. (1992) Genes & Dev. 6, 815-824). Here we further characterize the nucleic acid recognition properties of MF3 and present a mathematical analysis that evaluates the potential extent of telomere site occupancy by this factor. The substitution of dI at dG positions in telomeric DNA probes revealed that a single dG at any position within the internal repeat was sufficient for high affinity binding to MF3. The RNA analogs of high affinity DNA sites were not bound specifically by MF3, but the substitution of dU for dT in a DNA probe had little or no effect on binding. These data demonstrate that ribose ring structure is a critical feature of nucleoprotein complex formation, and this ribose specificity may enable MF3 to occupy sites of unusual DNA structure while minimizing interactions with cellular RNAs. Collectively, the nucleic acid binding properties of MF3 suggest that it may occupy a significant fraction of sites at telomere ends or other G-rich regions of altered DNA structure in vivo

Desempenho agronômico de grupos de cultivares de alface sistema orgânico no Distrito Federal.

Este trabalho teve com objetivo avaliar o desempenho agronômico de cultivares de alface crespa, lisa e americana cultivadas em sistema orgãnico.Trabalho apresentado no 4. Seminário de Agroecologia do Distrito Federal e Entorno, Brasília, DF