4,551 research outputs found
Elastocaloric Effect in Graphene Kirigami
Kirigami, a traditional Japanese art of paper-cutting, has recently been
explored for its elastocaloric effect (ECE) in kirigami-based materials (KMs),
where applying strain induces temperature changes. In this study, we
investigate the ECE in a nanoscale graphene kirigami (GK) monolayer,
representing the thinnest possible KM, to better understand this phenomenon.
Through molecular dynamics simulations, we analyze the temperature change and
coefficient of performance (COP) of the nanoscale GK architecture. Our findings
reveal that while GKs lack the intricate temperature changes observed in
macroscopic KMs, they exhibit a substantial temperature change of approximately
9.32 K (23 times higher than that of macroscopic KMs, which is about 0.4K) for
heating and -3.50 K for cooling. Additionally, they demonstrate reasonable COP
values of approximately 1.57 and 0.62, respectively. It is noteworthy that the
one-atom-thick graphene configuration prevents the occurrence of the complex
temperature distribution observed in macroscopic KMs.Comment: 14 pages, 06 figures, and 01 tabl
Perfil compósito para colector solar, respectivo método de produção e utilização
A presente invenção diz respeito a um perfil compósito para caixa modular
utilizada em colectores solares para aquecimento de águas para uso doméstico
ou industrial cujas principais vantagens passam pela: produção através de um
processo de extrusão, redução das perdas energéticas do colector solar devido
ao design com perfil alveolar, fácil portabilidade devido a redução do peso por
metro quadrado de painel, utilização de compósitos recicláveis na sua
composição usando entre outros: borracha de pneu usado reciclada, redução dos
tempos de montagem dos colectores solares, eliminação da necessidade de
colocação de isolantes adicionais à caixa modular e redução dos custos de produção
Liver proteomics unravel the metabolic pathways related to feed efficiency in beef cattle
Improving nutrient utilization efficiency is essential for livestock, given the current scenario of increasing demand for animal protein and sustainable resource use. In this context, understanding the biology of feed efficiency (FE) in beef cattle allows the development of markers for identification and selection of best animals for animal production. Thus, 98 young Nellore bulls were evaluated for FE and at the end of the experiment liver samples from six High Feed Efficient (HFE) and six Low Feed Efficient (LFE) animals were collected for protein extraction, digestion and analysis by HPLC-MS/MS. Data were analyzed for differential abundant proteins (DAPs), protein networks, and functional enrichment. Serum endotoxin was also quantified. We found 42 DAPs and 3 protein networks significantly related to FE. The main pathways associated with FE were: microbial metabolism; biosynthesis of fatty acids, amino acids and vitamins; glycolysis/gluconeogenesis; xenobiotic metabolism and; antigen processing and presentation. Serum endotoxins were significantly higher in LFE animals supporting the results. Therefore, the findings presented here confirmed the altered hepatic metabolism and pronounced hepatic inflammation in LFE animals supporting that the increased bacterial load is at least in part responsible for the hepatic lesions and inflammation in LFE animals9COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPsem informação[2014/12492-8; 2014/07566-2; 2014/02493-7; 2014/04937-
Measurement of the sensitivity function in time-domain atomic interferometer
submitted to IEEE Trans. Instrum. Meas.We present here an analysis of the sensitivity of a time-domain atomic interferometer to the phase noise of the lasers used to manipulate the atomic wave-packets. The sensitivity function is calculated in the case of a three pulse Mach-Zehnder interferometer, which is the configuration of the two inertial sensors we are building at BNM-SYRTE. We successfully compare this calculation to experimental measurements. The sensitivity of the interferometer is limited by the phase noise of the lasers, as well as by residual vibrations. We evaluate the performance that could be obtained with state of the art quartz oscillators, as well as the impact of the residual phase noise of the phase-lock loop. Requirements on the level of vibrations is derived from the same formalism
from in uterus to elderly
Immune system recognize and fight back foreign microorganisms and inner modifications that lead to deficient cell and tissue functions. During a dog's life, the immune system needs to adapt to different physiological conditions, assuring surveillance and protection in a careful and controlled way. Pregnancy alters normal homeostasis, requiring a balance between immunity and tolerance. The embryos and fetus should be protected from infections, while the female dog must tolerate the growing of semi-allografts in her uterus. After birth, newborn puppies are at great risk of developing infectious diseases, because their immune system is in development and immune memory is absent. Passive transfer of immunity through colostrum is fundamental for puppy survival in the first weeks of life, but hampers the development of an active immune response to vaccination. At the end of life, dogs experience a decline in the structure and functional competence of the immune system, compromising the immune responses to novel antigenic challenges, such as infections and vaccines. Therefore, the current article reviews the general processes related to the development of the dog´s immune system, providing an overview of immune activity throughout the dog's life and its implications in canine health, and highlighting priority research goals.publishersversionpublishe
I.C.E.: a Transportable Atomic Inertial Sensor for Test in Microgravity
We present our the construction of an atom interferometer for inertial
sensing in microgravity, as part of the I.C.E. (\textit{Interf\'{e}rom\'{e}trie
Coh\'{e}rente pour l'Espace}) collaboration. On-board laser systems have been
developed based on fibre-optic components, which are insensitive to mechanical
vibrations and acoustic noise, have sub-MHz linewidth, and remain frequency
stabilised for weeks at a time. A compact, transportable vacuum system has been
built, and used for laser cooling and magneto-optical trapping. We will use a
mixture of quantum degenerate gases, bosonic Rb and fermionic K,
in order to find the optimal conditions for precision and sensitivity of
inertial measurements. Microgravity will be realised in parabolic flights
lasting up to 20s in an Airbus. We show that the factors limiting the
sensitivity of a long-interrogation-time atomic inertial sensor are the phase
noise in reference frequency generation for Raman-pulse atomic beam-splitters
and acceleration fluctuations during free fall
How far ‘AUG-proximity effect’ goes?
Nonsense-mediated mRNA decay (NMD) is a surveillance pathway that recognizes and selectively degrades mRNAs carrying premature termination codons (PTCs). We have previously shown that mRNAs carrying a PTC located in close proximity to the translation initiation AUG codon escape NMD. This was called the “AUG-proximity effect”. The present work illustrates that the extension of the AUG-proximity effect, i.e. to what position in the open reading frame (ORF) an AUG-proximal PTC does not trigger NMD, is different between human a- and b-globin mRNAs. Remarkably, our data also demonstrate that, contrary to what occurs in the b-globin transcripts, a-globin mRNAs carrying an AUG-proximal PTC allow for efficient translation re-initiation, although it only partially explains their NMD resistance. In addition, our results reveal that in the a- and b-globin transcripts, the extension of the AUG-proximity effect is determined by the ORF sequence. Furthermore, we show how the mRNA secondary structure, which is affected by the ORF sequence, determines the AUG-proximity effect extension. Our data point out that the time taken to translate the short ORF, affected by its sequence and stability, besides being involved in modulating translation re-initiation, also plays an important role in establishing the extension of the AUG-proximity effect
Material compósito de granulado de borracha de pneus usados reciclado numa matriz polimérica
A presente invenção apresenta uma solução que incorpora e melhora a adesão
entre o granulado de borracha de pneu usado e a matriz polimérica, pela adição
de um agente compatibilizador que para além de compatibilizar os materiais,
promove a homogeneidade da mistura e consequentemente obtém-se um
material com boas propriedades mecânicas e com bom aspecto superficial. A
presente invenção consiste na apresentação de novas formulações de materiais
que incorporam borracha de pneu usado em matrizes poliméricas termoplásticas
utilizando um agente compatibilizador. Desta mistura obtêm-se produtos com composição de borracha de pneu usado com uma matriz polimérica, recorrendo a
aditivos para melhorar as propriedades finais do compósito. O custo é primordial para competir com produtos feitos de matérias virgens e como tal, este processo visa
reduzir o custo do produto bem como a quantidade relativa da matéria virgem utilizada e o reaproveitamento da borracha reciclada
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