Extending the limits of wireless power transfer to miniaturized implantable electronic devices

Implantable electronic devices have been evolving at an astonishing pace, due to the development of fabrication techniques and consequent miniaturization, and a higher efficiency of sensors, actuators, processors and packaging. Implantable devices, with sensing, communication, actuation, and wireless power are of high demand, as they pave the way for new applications and therapies. Long-term and reliable powering of such devices has been a challenge since they were first introduced. This paper presents a review of representative state of the art implantable electronic devices, with wireless power capabilities, ranging from inductive coupling to ultrasounds. The different power transmission mechanisms are compared, to show that, without new methodologies, the power that can be safely transmitted to an implant is reaching its limit. Consequently, a new approach, capable of multiplying the available power inside a brain phantom for the same specific absorption rate (SAR) value, is proposed. In this paper, a setup was implemented to quadruple the power available in the implant, without breaking the SAR limits. A brain phantom was used for concept verification, with both simulation and measurement data.This work is supported by FCT with the reference project PTDC/EEI-TEL/5250/2014, by FEDER funds through Projecto 3599-Promover a Produção Científica e Desenvolvimento Tecnológico e a Constituição de Redes Temáticas (3599-PPCDT) and by grant SFRH/BD/116554/2016.info:eu-repo/semantics/publishedVersio

Cave-Dwelling Populations of the Monstrous Rainfrog (Craugastor pelorus) from Mexico

Amphibians are known cave dwellers, and a few anurans have shown to make exploratory or opportunistic use of subterranean environments. We report on the use of karst ecosystems and cavernicolous environments by the monstrous rainfrog Craugastor pelorus in Chiapas and Tabasco (Mexico). Individuals were found in crevices and wall depressions within the twilight zone of the cave, both during the day and at night. Although threatened by human activities and often severely understudied, caves are the last refugia for some endangered species. This report allows us to extend the known distribution of the species, increase our knowledge on a threatened species, and better understand the biodiversity and ecology of cave environments.info:eu-repo/semantics/publishedVersio

Influence of HOTAIR rs920778 and rs12826786 genetic variants on prostate cancer risk and progression-free survival

Aim: Evaluate the impact of the single nucleotide polymorphisms rs920778 and rs12826786 in the long noncoding RNA HOTAIR in the susceptibility and prognosis of prostate cancer (PCa) patients. Patients & methods: HOTAIR single nucleotide polymorphisms were genotyped by restriction fragment length polymorphism in 151 PCa cases and 180 cancer-free controls. Odds ratio, 95% CIs and prognostic significance were calculated. Results: Our data showed no statistically significant associations between HOTAIR polymorphic variants in rs920778 and rs12826786 and PCa susceptibility. However, the CC genotype in rs12826786 was significantly associated with shorter biochemical recurrence-free survival in pT3-stage PCa patients. Conclusion: Our results indicate that HOTAIR rs12826786 CC genotype may be an independent prognostic biomarker in a particular subset of PCa tumors.Fundação para a Ciência e Tecnologia (IF/00601/2012 to BM Costa; SFRH/BD/52287/2013 to AI Oliveira; SFRH/BD/88220/2012 to AX Magalhaes), Fundação Calouste Gulbenkian (BM Costa), Liga Portuguesa Contra o Cancro (BM Costa) and Inter-University Doctoral Programme in Ageing and Chronic Disease (PhDOC; to AI Oliveira and AX Magalhaes). Project co-financed by Programa Operacional Regional do Norte (ON.2-O Novo Norte), Quadro de Referencia Estratégico Nacional (QREN), Fundo Europeu de Desenvolvimento Regional (FEDER) and a grant (74-CI-IPOP) from Research Center of Portuguese Oncology Institute of Porto (C Jeronimo).info:eu-repo/semantics/publishedVersio

Fast calculation of spectral optical properties and pigment content detection in human normal and pathological kidney

A fast calculation method was used to obtain the spectral optical properties of human normal and pathological (chromophobe renal cell carcinoma) kidney tissues. Using total transmittance, total reflectance and collimated transmittance spectra acquired from ex vivo kidney samples, the spectral optical properties of both tissues, namely the absorption, the scattering and the reduced scattering coefficients, as well as the scattering anisotropy, dispersion and light penetration depth, were calculated between 200 and 1000 nm. Analysis of the mean ab sorption coefficient spectra of the kidney tissues showed that both contain melanin and lipofuscin, and that 83 % of the melanin in the normal kidney converts into lipofuscin in the pathological kidney.info:eu-repo/semantics/publishedVersio

Assessment of potato peel and agro-forestry biochars supplementation on in vitro ruminal fermentation

UIDB/50006/2020 UIDB/04033/2020 grant ref. PDE/BDE/114434/2016 DL 57/2016 -Norma transitória.Background. The awareness of environmental and socio-economic impacts caused by greenhouse gas emissions from the livestock sector leverages the adoption of strategies to counteract it. Feed supplements can play an important role in the reduction of the main greenhouse gas produced by ruminants-methane (CH4). In this context, this study aims to assess the effect of two biochar sources and inclusion levels on rumen fermentation parameters in vitro. Methods. Two sources of biochar (agro-forestry residues, AFB, and potato peel, PPB) were added at two levels (5 and 10%, dry matter (DM) basis) to two basal substrates (haylage and corn silage) and incubated 24-h with rumen inocula to assess the effects on CH4 production and main rumen fermentation parameters in vitro. Results. AFB and PPB were obtained at different carbonization conditions resulting in different apparent surface areas, ash content, pH at the point of zero charge (pHpzc), and elemental analysis. Relative to control (0% biochar), biochar supplementation kept unaffected total gas production and yield (mL and mL/g DM, pD0.140 and pD0.240, respectively) and fermentation pH (p D 0.666), increased CH4 production and yield (mL and mL/g DM, respectively, pD0.001) and ammonia-N (NH3-N, pD0.040), and decreased total volatile fatty acids (VFA) production (p < 0.001) and H2 generated and consumed (p ≤ 0.001). Biochar sources and inclusion levels had no negative effect on most of the fermentation parameters and efficiency. Acetic.propionic acid ratio (pD0.048) and H2 consumed (pD0.019) were lower with AFB inclusion when compared to PPB. Biochar inclusion at 10% reduced H2 consumed (p < 0.001) and tended to reduce total gas production (pD0.055). Total VFA production (pD0.019), acetic acid proportion (pD0.011) and H2 generated (pD0.048) were the lowest with AFB supplemented at 10%, no differences being observed among the other treatments. The basal substrate affected most fermentation parameters independently of biochar source and level used. Discussion. Biochar supplementation increased NH3-N content, iso-butyric, iso-valeric and valeric acid proportions, and decreased VFA production suggesting a reduced energy supply for microbial growth, higher proteolysis and deamination of substrate N, and a decrease of NH3-N incorporation into microbial protein. No interaction was found between substrate and biochar source or level on any of the parameters measured. Although AFB and PPB had different textural and compositional characteristics, their effects on the rumen fermentation parameters were similar, the only observed effects being due to AFB included at 10%. Biochar supplementation promoted CH4 production regardless of the source and inclusion level, suggesting that there may be other effects beyond biomass and temperature of production of biochar, highlighting the need to consider other characteristics to better identify the mechanism by which biochar may influence CH4 production.publishersversionpublishe

Magnetic and transport properties of diluted granular multilayers

The magnetic and transport properties of Co80Fe20t /Al2O34 nm multilayers with low nominal thicknesses t=0.7 and 0.9 nm of Co80Fe20 granular layers are studied. Magnetic studies find a superparamagnetic state above the blocking temperature Tb of field-cooled/zero-field-cooled splitting that grows with t and decreases with H. The low-voltage Ohmic tunnel transport passes to non-Ohmic IV3/2 law for applied fields above 500 V/cm. At fixed V, the temperature dependence of conductance reveals an anomalous dip around 220 K, which can be attributed to the effect of surface contamination by supercooled water. Current-in-plane tunnel magnetoresistance MR ratio tends, at lower t, to higher maximum values 8% at room temperature but to lower field sensitivity. This may indicate growing discorrelation effect e.g., between shrinking areas of correlated moments in this regime and corroborates the deficit of granule magnetization estimated from the Inoue–Maekawa MR fit, compared to that from direct magnetization measurements. MR displays a mean-field-like critical behavior when t approaches the point of superparamagnetic/ superferromagnetic transition tc1.3 nm at room temperature from below, different from the formerly reported percolationlike behavior at approaching it from above.With growing temperature, MR reveals, beyond the common decrease, an anomalous plateau from Tb30–50 K up to some higher value T150–200 K, not seen at higher t

Preservando a memória das pedras

Para as comunidades do passado o mundo “físico” seria entendido como cheio de propriedades significantes. No seguimento dos trabalhos de Ingold (2000), Bradley (2000, 2009), ou Scarre (2009), o que hoje vemos como material inerte seria considerada “viva”. Essa será a presente perspetiva de abordagem. Certos afloramentos naturais estão associados a lendas ou crenças muitas vezes ligadas a criaturas mágicas ou estranhas “habitando” no seu interior ou “vivendo” entre eles o que, em muitos casos, converge na determinação de um lugar com denominação. Tal como as pessoas, os afloramentos podem ser vistos como entidades que podem e fazem a diferença, atuando como agentes que corporizam significados e histórias (Tilley, 2002, 2004), consequentemente passados ao longo de gerações. Durante a Pré-História alguns afloramentos foram gravados com motivos; outros, pela sua forma peculiar ou estranha, formaram parte de mitos históricos e de folclore. Em ambos os casos os afloramentos funcionaram como contentores de memória. Pretende-se focar a importância da fotogrametria e do registo tridimensional deste tipo de património cultural (frequentemente em risco de destruição), mostrando o potencial desta ferramenta na inventariação e no estudo deste tipo de lugares de memória. Muitos casos de estudo apresentados foram objeto de análise em diferentes projetos, desenvolvidos de acordo com metodologias da Arqueologia e Antropologia Cultural aplicadas ao Noroeste da Ibéria. Este tipo de trabalho é fundamental tendo em conta a interpretação e o entendimento do papel dos afloramentos para as sociedades humanas e o seu contributo para a construção das paisagens pré-históricas e presentes.To past and pre-modern societies “physical” world was full of significant properties. Following the works of Ingold (2000), Bradley (2000, 2009), Gosden (2009), or Scarre (2009), what today is seen as inert matter was considered “alive”, and that should be the present perspective. Certain natural outcrops are attached to legends and beliefs often referred to magical or odd creatures “inhabiting” inside or “living” within them, and the majority is linked to place-names. Like people, outcrops can be seen as entities that can and make difference, acting as agents that embody meanings and stories (Tilley, 2002, 2004) subsequently passed over generations. During Prehistory some outcrops were engraved with motifs; others, by their odd or peculiar forms, formed part of historical myths and folklore. In both cases outcrops worked as memory containers. It is pretended to focus on the importance of photogrammetry and tridimensional record of this kind of cultural heritage (frequently in risk or destruction) and to show the potential of this tool in matters of inventory and study of these places of memory. Several case studies presented were matter of analysis in different projects and developed according to archaeological and cultural anthropology methodologies applied to the Northwest of Iberia. This type of work is fundamental to achieve rock art interpretations and to understand the role of outcrops to human societies and their contribution to the construction of prehistoric and present landscape

Review: Heads or Tails? Toward a Clear Role of Biochar as a Feed Additive on Ruminant’s Methanogenesis

The use of biochar has been suggested as a promising strategy in bio-waste management and greenhouse gases mitigation. Additionally, its use, as a feed additive, in ruminants has been reported to have contrasting effects on enteric methane production. Hence, this chapter intends to overview the most relevant literature that exploited the use of biochar as a mitigation strategy for methane. This includes the reported effects of biochar on methane production and rumen fermentation observed in in vitro and in vivo assays, as well as manure’s methane emission. The information available about the biochar and the experimental conditions used in the different studies is still limited, which created additional challenges in identifying the biological mechanisms that potentially drive the contrasting results obtained. Nevertheless, it is clear from the current state-of-the-art that biochar may be a key player in the modulation of gut fermentation and in the reduction of greenhouse gases produced by ruminants that need to be consolidated by further research