566 research outputs found
Enhanced dimerization of TiOCl under pressure: spin-Peierls - to - Peierls transition
We report high-pressure x-ray diffraction and magnetization measurements
combined with ab-initio calculations to demonstrate that the high-pressure
optical and transport transitions recently reported in TiOCl, correspond in
fact to an enhanced Ti3+-Ti3+ dimerization existing already at room
temperature. Our results confirm the formation of a metal-metal bond between
Ti3+ ions along the b-axis of TiOCl, accompanied by a strong reduction of the
electronic gap. The evolution of the dimerization with pressure suggests a
crossover from the spin-Peierls to a conventional Peierls situation at high
pressures.Comment: 9pages, 4 figure
Sexual dimorphism in brown adipose tissue activation and white adipose tissue browning
The present narrative review gathers the studies reported so far, addressing sex differences in the effects of cold exposure, feeding pattern and age on brown adipose tissue (BAT) thermogenesis and white adipose tissue (WAT) browning. In rodents, when exposed to decreasing temperatures, females activate thermogenesis earlier. Results obtained in humans go in the same line, although they do not provide results as solid as those obtained in rodents. Regarding the effects of overfeeding, interesting sex differences on BAT thermogenic capacity have been reported, and the greater or lower sensitivity of each sex to this dietary situation seems to be dependent on the type of feeding. In the case of energy restriction, females are more sensitive than males. In addition, sex differences have also been observed in thermogenesis changes induced by phenolic compound administration. During sexual development, an increase in BAT mass and BAT activity takes place. This phenomenon is greater in boys than in girls, probably due to its relation to muscle-mass growth. The opposite situation takes place during ageing, a lifespan period where thermogenic capacity declines, this being more acute in men than in women. Finally, the vast majority of the studies have reported a higher susceptibility to developing WAT browning amongst females. The scarcity of results highlights the need for further studies devoted to analysing this issue, in order to provide valuable information for a more personalised approach
Virulência de fungos entomopatogênicos a ninfas de Bemisia tabaci biótipo B (Hemiptera: Aleyrodidae).
Neste trabalho, avaliou-se a virulência de 14 isolados dos fungos Beauveria bassiana senso latu, Isaria fumosorosea e Lecanicillium spp. sobre ninfas de segundo ínstar de Bemisia tabaci biótipo B em folhas de feijoeiro (cv. Pérola) sob condições de laboratório (26°C, UR>80%, 14 h luz) e, em seguida, determinou-se a capacidade desses isolados em produzir inóculo sobre cadáveres do inseto
Short communication: Effect of subclinical mastitis on reproductive performance of Holstein dairy cows in the Northwest of Spain
Aim of study: To investigate the effect of subclinical mastitis (SCM) before and after first artificial insemination (AI), characterized by a somatic cell count (SCC) higher than 200×103 cell/mL, on reproductive performance including first service conception rate (FSCR) and pregnancy loss (PL) in Holstein dairy cows.
Area of study: The central area of Lugo, Galicia, Spain.
Material and methods: This retrospective study was conducted on herd database of a population of 80 commercial Holstein dairy cow farms. A total number of 2053 lactations were included in this study. A binary logistic regression was carried out to analyse all data.
Main results: The results of this study indicated that cows that registered a SCC lower than 200×103 cell/mL within 30 days after first AI were more likely to conceive pregnancy than cows with a higher SCC (31.2% and 25.1% FSCR, respectively; OR=1.285, 95% CI=1.000-1.653). Additionally, an increased SCC neither 30 days before nor 30 days after first AI had a negative effect on prevalence of PL in dairy cows.
Research highlights: These findings revealed that SCM within 30 days after first AI negatively affected FSCR, whilst 30 days before first AI did not affect it. Therefore, it could be suggested that preventing subclinical mastitis after first AI, during a critical period of 30 days, is important to maximize the reproductive performance of dairy cows
Flutuação populacional de artrópodes no milho em áreas de transição para produção orgânica.
Com o objetivo de construir um modelo de desenvolvimento agrícola sustentável em um assentamento no Estado de Goiás, procurou-se viabilizar o processo de transição de um sistema convencional de produção de grãos para um sistema sustentável, que recupere o solo, preserve os recursos naturais e o capital social. Neste trabalho, estudou-se o efeito de diferentes coberturas vegetais (adubos verdes) semeadas no mês de abril sobre a população de artropódes da parte aérea do milho semeado nas águas (outubro-novembro)
Coexistence of Two Rare Sarcomas: Primary Leiomyosarcoma of Bone and Epithelioid Hemangioendothelioma of the Liver
A 33-year-old woman sought medical attention for a painful swelling of the left
ankle. Plain radiographs revealed an osteolytic lesion involving the left distal tibia.
An excisional biopsy provided the diagnosis of leiomyosarcoma in the tibia. A
staging work-up was performed and an abdominal CT showed 4 liver hypodense
lesions in both lobes with peripheral contrast enhancement. A liver biopsy
confirmed the diagnosis of epithelioid hemangioendothelioma of the liver. No
association between these two entities has been described before. This case
introduces the importance of the pathological confirmation of apparent metastatic
lesions in low grade sarcomas and provides a review of the literature of both
tumours
Teor diferencial de ácidos fenólicos em variedades de algodoeiro infestadas ou não por mosca branca, Bemisia Tabaci.
Cost analysis of the management of brain metastases in patients with advanced ALK+ NSCLC: alectinib versus crizotinib
Aim: To estimate management cost of NSCLC ALK+ patients with and without brain metastasis (BM), and to compare annual costs in patients treated with alectinib or crizotinib. Methods: Management cost/year (euro 2018) in patients with and without BM was estimated with disaggregated resource consumption provided by local oncologists, including medical visits, hospitalizations, diagnostic/laboratory tests, imaging techniques and surgical procedures. The comparison of costs/year with alectinib and crizotinib, considered the cumulative 12-month incidence of BM in ALEX trial (9.4 and 41.4%, respectively). Results: Management cost was euro6173.42/patient-year without BM and euro21,637.50/patient-year with BM. With alectinib, average cost/patient was lower than crizotinib (euro4948.51/patient-year). Conclusion: Prevention of BM with alectinib may result in reductions of cost/year in the management of advanced ALK+ NSCLC
A Simple Entropic-Driving Separation Procedure of Low-Size Silver Clusters, Through Interaction with DNA
Synthesis and purification of metal clusters without strong binding agents by wet chemical methods are very attractive for their potential applications in many research areas. However, especially challenging is the separation of uncharged clusters with only a few number of atoms, which renders the usual techniques very difficult to apply. Herein, we report the first efficient separation of Ag2 and Ag3 clusters using the different entropic driving forces when such clusters interact with DNA, into which Ag3 selectively intercalates. After sequential dialysis of the samples and denaturalizing the DNA-Ag3 complex, pure Ag2 can be found in the dialysate after extensive dialysis. Free Ag3 is recovered after DNA denaturation
Parasitismo de ninfas de Bemisia tabaci biótipo B, em cultivos de soja no estado de Goiás.
Esse trabalho objetivou-se levantar o parasitismo de ninfas de mosca-branca em lavouras comerciais de soja (não orgânico)
- …