Reducing Beat Frequency Oscillation in a Two-phase Sliding Mode-controlled Voltage Regulator Module

During static and dynamic loading conditions, voltage regulator modules (VRMs) are expected to provide regulated voltage with minimal ripple even at high current requirement.  Compared to regular power supplies, VRMs repetitively experience high-frequency loading conditions that is greatly dependent on the software running in the processor utilizing them. In the scenario that when the transient load frequency is near the VRM’s switching frequency, high-magnitude and low-frequency oscillations are observed at the phase currents.  This phenomenon is called the beat frequency oscillation.  In this study, the sliding mode control principle is employed to both the voltage and current share loops of the VRM to reduce the phase currents’ beat frequency oscillations. A fixed frequency sliding mode controller is derived and extensively evaluated using the PSIM simulator.  Our results show that while maintaining equal load sharing among VRMs at less than 5% sharing error and various types of loading conditions, the sliding mode controller can reduce the beat frequency oscillation phenomenon to 20 kHz at maximum with reduced peak current values.   The output voltage is also regulated within the desired ±1.65% band

Doença inflamatória pélvica: um desfecho inesperado

Pelvic inflammatory disease is a polymicrobial infection of the upper genital tract, representing the most common complication of sexually transmitted diseases. Multiple agents are frequently involved, although some unusual agents have also been reported. The presentation is frequently sub-clinical, but may assume an acute form. We report a clinical case of a 39-year-old woman with recurrent pelvic inflammatory disease, resistant to systemic antibiotics, submitted to an exploratory surgery, with a histologic finding of tubal cysticercosis

Spillover events of rabbit haemorrhagic disease virus 2 (recombinant GI.4P-GI.2) from Lagomorpha to Eurasian badger

Rabbit haemorrhagic disease (RHD) is a major threat to domestic and wild European rabbits. Presently, in Europe, the disease is caused mainly by Rabbit haemorrhagic disease virus 2 (RHDV2/b or Lagovirus europaeus GI.2), the origin of which is still unclear, as no RHDV2 reservoir hosts were identified. After the RHDV2 emergence in 2010, viral RNA was detected in a few rodent species. Furthermore, RHDV2 was found to cause disease in some hare species resembling the disease in rabbits, evidencing the ability of the virus to cross the species barrier. In this study, through molecular, histopathologic, antigenic and morphological evidences, we demonstrate the presence and replication of RHDV2 in Eurasian badgers (Meles meles) found dead in the district of Santarém, Portugal, between March 2017 and January 2020. In two of these seven animals, we further classify the RHDV2 as a Lagovirus europaeus recombinant GI.4P‐GI.2. Our results indicate that Meles meles is susceptible to RHDV2, developing systemic infection, and excreting the virus in the faeces. Given the high viral loads seen in several organs and matrices, we believe that transmission to the wild rabbit is likely. Furthermore, transmission electron microscopy data shows the presence of Calicivirus compatible virions in the nucleus of hepatocytes, which has not been demonstrated before and constitutes a paradigm shift for caliciviruses’s replication cycle

3D-Printed Ergonomic Tool Handles

Although hand tools serve as an instrument for extending one’s capabilities through the use of hands, the comfort it brings is important especially since the welfare of the user is at stake. Aside from using the hand tools repetitively and with an awkward posture, the tool handle compositions and design also contribute to accumulating some work-related musculoskeletal disorders that require further attention in the long run. To provide a long-term solution, 3D-printed new designs of six commonly used hand tools that fit the average hand measurements of Filipinos have been developed. The hand tools are printed using two filaments namely; thermoplastic polyurethane (TPU) which was found to be skin-friendly and polylactic acid (PLA) which is proven to be more functional, both are used on the outer and inner layer of the handle, respectively. The 3D-printed tool handles were evaluated through the use of a comfort questionnaire for hand tools distributed to 10 respondents per tool handle testing, results show that 3D-printed tool handles are found to be more comfortable and convenient rather than the commercial ones. Meanwhile, the researchers note that the adequate length of tool handles may also vary according to functions and not rely alone on the average hand measurements

Anisotropy in the dielectric spectrum of hydration water and its relation to water dynamics

Proteins, molecules, and macromolecular assemblies in water are surrounded by a nanometer-sized hydration layer with properties very different from bulk water. Here, we use classical molecular dynamics simulations to study the dielectric response of hydration water next to hydrophobic and hydrophilic planar surfaces. We find the interfacial dielectricabsorption of water to be strongly anisotropic: compared to bulk water, which shows a broad dielectricabsorption maximum around 15 GHz in the imaginary part of the dielectric function, the absorption for electric fields parallel to the surface is of similar strength and shows a slight redshift, while for perpendicular electric fields it is strongly attenuated and blueshifted. This anisotropy is generic for hydrophobic and hydrophilic surfaces. From our spatially resolved dielectric functions and a modified Maxwell-Garnett theory that accounts for anisotropic hydration layers around spherical particles, the dielectricabsorption of solutions of organic molecules and micelles is derived to exhibit the experimentally known attenuation in combination with a redshift. These two features are traced back to the subtle interplay of interfacial depolarization effects and the dielectricanisotropy in the hydration layer. By a detailed analysis of the individual water molecule dynamics the perpendicular blueshift is shown not to be linked to accelerated water reorientation, but rather to dielectric boundary effects. Carefully conducted angularly resolved experiments at planar aqueous interfaces will be able to resolve this dielectricanisotropy and thus to confirm the subtle connection between spectralabsorption features and the molecular water dynamics in hydration layers

Range expansion of the Bluetongue vector, Culicoides imicola, in continental France likely due to rare wind-transport events

The role of the northward expansion of Culicoides imicola Kieffer in recent and unprecedented outbreaks of Culicoides-borne arboviruses in southern Europe has been a significant point of contention. We combined entomological surveys, movement simulations of air-borne particles, and population genetics to reconstruct the chain of events that led to a newly colonized French area nestled at the northern foot of the Pyrenees. Simulating the movement of air-borne particles evidenced frequent wind-transport events allowing, within at most 36 hours, the immigration of midges from north-eastern Spain and Balearic Islands, and, as rare events, their immigration from Corsica. Completing the puzzle, population genetic analyses discriminated Corsica as the origin of the new population and identified two successive colonization events within west-Mediterranean basin. Our findings are of considerable importance when trying to understand the invasion of new territories by expanding species

ÁCAROS TROMBICULÍDEOS: REVISÃO DE UMA PARASITOSE NEGLIGENCIADA EM ANIMAIS DE COMPANHIA

A trombiculose é uma parasitose causada por ácaros trombiculídeos (Acari: Trombiculidae) que afeta vertebrados, incluindo cães, gatos e o ser humano. É a fase larvar dos ácaros trombiculídeos que se caracteriza por ser parasita obrigatório e responsável pelo aparecimento de sinais clínicos. Estes incluem prurido, várias lesões cutâneas, podendo, em alguns casos, surgir distúrbios gastrointestinais, neurológicos ou mesmo a morte do animal quando as infestações são massivas. Apesar da sua distribuição mundial, incluindo em Portugal, esta é uma parasitose negligenciada, sobretudo no contexto da medicina veterinária de animais de companhia. Os estudos existentes são escassos, contribuindo para o seu desconhecimento, e a sua verdadeira prevalência nestes animais é pouco conhecida a nível mundial. Apesar do seu papel enquanto vetores de agentes patogénicos não ser claro, alguns estudos já demonstraram a presença de ADN de Anaplasma spp., Bartonella spp., Borrelia spp. e Rickettsia spp., em trombiculídeos. O facto de os ácaros trombiculídeos afetarem várias espécies animais, incluindo os animais de companhia e o ser humano, bem como o seu potencial papel no ciclo de manutenção de vários agentes infeciosos, revela a importância de um maior conhecimento acerca desta parasitose, tanto ao nível da comunidade científica como da comunidade médico veterinária. Assim, esta revisão pretende reunir os dados disponíveis à data quanto à epidemiologia, características clínicas e tratamento desta parasitose, com especial enfoque em Portugal

An interferon-inducible neutrophil-driven blood transcriptional signature in human tuberculosis

Tuberculosis (TB), caused by infection with Mycobacterium tuberculosis (M. tuberculosis), is a major cause of morbidity and mortality worldwide and efforts to control TB are hampered by difficulties with diagnosis, prevention and treatment 1,2. Most people infected with M. tuberculosis remain asymptomatic, termed latent TB, with a 10% lifetime risk of developing active TB disease, but current tests cannot identify which individuals will develop disease 3. The immune response to M. tuberculosis is complex and incompletely characterized, hindering development of new diagnostics, therapies and vaccines 4,5. We identified a whole blood 393 transcript signature for active TB in intermediate and high burden settings, correlating with radiological extent of disease and reverting to that of healthy controls following treatment. A subset of latent TB patients had signatures similar to those in active TB patients. We also identified a specific 86-transcript signature that discriminated active TB from other inflammatory and infectious diseases. Modular and pathway analysis revealed that the TB signature was dominated by a neutrophil-driven interferon (IFN)-inducible gene profile, consisting of both IFN-γ and Type I IFNαβ signalling. Comparison with transcriptional signatures in purified cells and flow cytometric analysis, suggest that this TB signature reflects both changes in cellular composition and altered gene expression. Although an IFN signature was also observed in whole blood of patients with Systemic Lupus Erythematosus (SLE), their complete modular signature differed from TB with increased abundance of plasma cell transcripts. Our studies demonstrate a hitherto under-appreciated role of Type I IFNαβ signalling in TB pathogenesis, which has implications for vaccine and therapeutic development. Our study also provides a broad range of transcriptional biomarkers with potential as diagnostic and prognostic tools to combat the TB epidemic

Advances in technologies for propagation and domestication of plants of economic and environmental interest in Argentina

En el Laboratorio de Estudios de la Madera de la Facultad de Ciencias Agrarias y Forestales de la Universidad Nacional de La Plata, Argentina, se implementa el proyecto de desarrollo tecnológico denominado Métodos y tecnologías de propagación y domesticación de plantas para el desarrollo de una bioeconomía local basada en la biodiversidad. El objetivo del mismo es desarrollar, optimizar y adaptar nuevas metodologías y tecnologías de propagación y conservación de recursos genéticos vegetales para la producción de plantas en nuevo escenario de la bioeconomía nacional. La diversidad está en la base de la bioeconomía, y muchas veces el material vegetal para plantar para diferentes fines es escaso. Las especies contempladas en éste proyecto son: Quercus sp.; Polylepis tarapacana; Prosopis alpataco, Eranthemun pulchelum y Heteropteris angustifolia Griseb. En este trabajo se comunican algunos de los avances alcanzados aplicando diferentes enfoques para la producción de plantas de calidad (semillas, cultivo de tejidos in vitro, macropropagación y plantines en contenedores).The Timber Research Laboratory of the Faculty of Agricultural and Forestry Sciences of the National University of La Plata (LIMAD), Argentina, implements the technological development project called Methods and technologies of plant propagation and domestication for the development of a local bioeconomy based on biodiversity. Its objective is to develop, optimize and adapt new methodologies and technologies for the propagation and conservation of plant genetic resources for the production of plants in a new scenario of national bioeconomy. Diversity is at the base of bioeconomy, and often planting plant material for different purposes is scarce. The species covered by this project are: Quercus sp. (exotic forest); Polylepis tarapacana (native forest); Prosopis alpataco. (multipurpose native forestry), Eranthemun pulchelum and Heteropteris angustifolia Griseb (ornamental species of great potential and use in green roofs). This work communicates some of the progress made by applying different approaches to the production of quality plants (seeds, in vitro tissue culture, macro propagation and seed container planting).Fil: Sharry, E.S.. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; ArgentinaFil: Weber, C.. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; ArgentinaFil: Cellini, M.. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; ArgentinaFil: Lopez, Victoria Lien. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Boeri, P.. Universidad Nacional de Rio Negro. Sede Alto Valle y Valle Medio.; ArgentinaFil: Roussy, L.. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; ArgentinaFil: Sceglio, P.. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; ArgentinaFil: Ramilo, D.. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; ArgentinaFil: Galarco, S.. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; Argentin

Enhanced Monocyte Response and Decreased Central Memory T Cells in Children with Invasive Staphylococcus aureus Infections

Staphylococcus aureus has emerged as a significant pathogen causing severe invasive disease in otherwise healthy people. Despite considerable advances in understanding the epidemiology, resistance mechanisms, and virulence factors produced by the bacteria, there is limited knowledge of the in vivo host immune response to acute, invasive S. aureus infections. Herein, we report that peripheral blood mononuclear cells from patients with severe S. aureus infections demonstrate a distinctive and robust gene expression profile which is validated in a distinct group of patients and on a different microarray platform. Application of a systems-wide modular analysis framework reveals significant over-expression of innate immunity genes and under-expression of genes related to adaptive immunity. Simultaneous flow cytometry analyses demonstrated marked alterations in immune cell numbers, with decreased central memory CD4 and CD8 T cells and increased numbers of monocytes. CD14+ monocyte numbers significantly correlated with the gene expression levels of genes related to the innate immune response. These results demonstrate the value of applying a systems biology approach that reveals the significant alterations in the components of circulating blood lymphocytes and monocytes in invasive S. aureus infections