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91.
Renata Reisfeld Tsiala Saraidarov Gerard Panzer Viktoria Levchenko Michael Gaft 《Optical Materials》2011,34(2):351-354
In our search for efficient Luminescent Solar Concentrators (LSC) we have prepared polyvinyl pyrrolidone (PVP) films incorporated by ethylenediamine tetraacetic acid (EDTA) complex of europium and co-doped with silver nanoparticles (NPs). Steady state fluorescence was studied under weak and strong excitation. Dynamical study was performed by second harmonic of Nd laser. Under weak excitation the fluorescence of europium co-doped with silver plasmons increased by a factor of three and excited by continuous laser by a factor of 50. The lifetimes of films doped by the complex were 755 μs and co-doped with silver nanoparticles 946 μs. This is the first finding that the photon density accumulates the number of plasmons interacting with electronic states of europium increasing its transition probability resulting in the strong intensification of fluorescence. In dynamical measurements of lifetimes a single pulse does not provide enough energy to create such number of plasmons. 相似文献
92.
Renata Braga Araújo Guilherme Henrique Trielli Ferreira Gustavo Henrique Orair Wagner Meira Jr. Renato Antônio Celso Ferreira Dorgival Olavo Guedes Neto Mohammed Javeed Zaki 《International journal of parallel programming》2008,36(2):226-249
Analyzing gene expression patterns is becoming a highly relevant task in the Bioinformatics area. This analysis makes it possible
to determine the behavior patterns of genes under various conditions, a fundamental information for treating diseases, among
other applications. A recent advance in this area is the Tricluster algorithm, which is the first algorithm capable of determining
3D clusters (genes × samples × timestamps), that is, groups of genes that behave similarly across samples and timestamps.
However, even though biological experiments collect an increasing amount of data to be analyzed and correlated, the triclustering
problem remains a bottleneck due to its NP-Completeness, so its parallelization seems to be an essential step towards obtaining
feasible solutions. In this work we propose and evaluate the implementation of a parallel version of the Tricluster algorithm
using the filter-labeled-stream paradigm supported by the Anthill parallel programming environment. The results show that
our parallelization scales well with the data size, being able to handle severe load imbalances that are inherent to the problem.
Further more, the parallelization strategy is applicable to any depth-first searches. 相似文献
93.
Mrcia A. F. S. Neves Fernanda M. B. Coutinho Marcos L. Dias Renata A. Simo Carlos A. Achete 《应用聚合物科学杂志》2002,84(3):541-551
Macroporous poly(styrene‐co‐divinylbenzene) and poly(divinylbenzene) beads were synthesized by modified suspension polymerization in the presence of different mixtures of toluene and heptane as porogen agent. Through atomic force microscopy, it was possible to identify the microspheres and the channels between them that constitute the bead pores. It was also possible to make a comparison with the results obtained by nitrogen desorption, a traditional technique used to determine the porosity of macroporous copolymers in the dry state. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 541–551, 2002; DOI 10.1002/app.10290 相似文献
94.
Renata Cardoso Magagnin Maria Solange Gurgel de Castro Fontes Rosio Fernandez Baca Salcedo 《土木工程与建筑:英文版》2014,(12):1567-1574
This paper presents an assessment of the spatial quality of a pedestrian street located in downtown Bauru, S~o Paulo State, Brazil, from the application of some urban sustainability indicators. Multi-method was used to evaluate the thermal comfort quality of users, urban accessibility and preservation of architectural heritage. The results show that the sustainability indicators, apart from being effective tools in identifying problems, can assist local managers in decision making, planning and monitoring of pedestrian public space. These indicators contribute to a broad diagnosis of the pedestrian street and also the formulation of programs, projects and municipal policies, aimed at providing a better life quality for pedestrians. 相似文献
95.
Nogueira IR Carneiro G Yoshida MI de Oliveira RB Ferreira LA 《Drug development and industrial pharmacy》2011,37(9):1083-1089
Topical chemotherapy with paromomycin (PA) has been used as an alternative for the treatment of cutaneous leishmaniasis; however, poor skin penetration of this drug limits the efficacy of formulations. The objective of this work was to study the ability of the PA free base to form ion pairing with organic acids, as well as evaluate the effect of these compounds on the topical delivery of PA. PA permeation across intact skin was low, while drug penetration into skin from PA ion pairing was the higher than that observed for the PA base. Data obtained on the stripped skin, a damaged skin model, clearly showed that the ion pairing presented a potential to improve PA skin permeation. 相似文献
96.
The objective was to evaluate the association between the single nucleotide polymorphism at position +735 in the interleukin-8 receptor-α (CXCR1) gene (CXCR1c.735) and disease incidence, milk production, reproductive performance, and survival in Holstein cows. Three-hundred fifty Holstein cows were enrolled. No association was found between CXCR1c.735 genotype and retained fetal membranes, metritis, or endometritis. Incidence rate of clinical mastitis was associated with CXCR1c.735 genotype; cows with genotypes CC and GC had a decreased incidence rate of clinical mastitis compared with GG cows. Milk yield was associated with CXCR1c.735 genotype; cows with genotype GC had greater milk yield than GG cows. Hazard of pregnancy was not associated with CXCR1c.735 genotype. Cows that had clinical mastitis had decreased hazard of pregnancy, and cows that had endometritis tended to have a decreased hazard of pregnancy. Hazard of death or culling was not associated with CXCR1c.735 genotype. Multiparous cows and cows that had mastitis had increased hazard of death or culling. In contrast to what we expected, cows with the genotype GG had an increased incidence rate of clinical mastitis and decreased milk yield. 相似文献
97.
The objectives of this observational study were (1) to assess the time from the appearance of the amniotic sac (AS) or feet outside the vulva to birth in Holstein cows (primiparous and multiparous) with (dystocia) or without assistance (eutocia) at calving, and (2) to estimate reference times to be used as guidelines for obstetric intervention in Holstein cows that need assistance during difficult births. Cows (n = 92) from 1 commercial dairy operation were used in this study. Periparturient dairy cows (primiparous, n = 58; multiparous, n = 34) were placed in a maternity pen and constantly monitored until birth. The calving ease of cows, time from AS or feet appearance to birth, calving progress from a subset of 15 cows (frequency and duration of abdominal contractions during labor), calf birth weight, calf sex, and stillbirths (born dead or died within 24 h after birth) were recorded. The reference times for obstetric intervention during dystocia were estimated based on values from unassisted births (normal). The normal range of times from the appearance of AS or feet outside the vulva to birth was estimated based on the mean + 2 standard deviations (SD) of unassisted births. According to farm protocol, assistance was provided to cows without calving progress 80 min after AS appearance or earlier (e.g., to correct malpositions). Cows with dystocic births had a longer time from AS appearance to birth and increased incidence of stillbirth compared with cows with eutocic calvings. After the appearance of the AS, calving progress was evident every 15 min for eutocic births. The estimated reference times (mean + 2 SD) from AS appearance to birth were 69.7 min and from feet appearance to birth were 64.6 min for eutocic births. Findings from this study suggested that calving personnel should start assisting cows 70 min after AS appearance (or 65 min after feet appearance) outside the vulva. The time spent in labor (straining) combined with the time from the appearance of the AS or feet to birth, and the assessment of calving progress (as described for eutocic births) should be used as guidelines for obstetric intervention during difficult births under field conditions. These reference times should be interpreted in combination with adequate obstetrical knowledge and examination. 相似文献
98.
99.
Giulia Minniti Letícia Maria Pescinini-Salzedas Guilherme Almeida dos Santos Minniti Lucas Fornari Laurindo Sandra Maria Barbalho Renata Vargas Sinatora Lance Alan Sloan Rafael Santos de Argollo Haber Adriano Cressoni Araújo Karina Quesada Jesselina F. dos Santos Haber Marcelo Dib Bechara Katia Portero Sloan 《International journal of molecular sciences》2022,23(21)
Sarcopenia is a disease that becomes more prevalent as the population ages, since it is directly linked to the process of senility, which courses with muscle atrophy and loss of muscle strength. Over time, sarcopenia is linked to obesity, being known as sarcopenic obesity, and leads to other metabolic changes. At the molecular level, organokines act on different tissues and can improve or harm sarcopenia. It all depends on their production process, which is associated with factors such as physical exercise, the aging process, and metabolic diseases. Because of the seriousness of these repercussions, the aim of this literature review is to conduct a review on the relationship between organokines, sarcopenia, diabetes, and other metabolic repercussions, as well the role of physical exercise. To build this review, PubMed-Medline, Embase, and COCHRANE databases were searched, and only studies written in English were included. It was observed that myokines, adipokines, hepatokines, and osteokines had direct impacts on the pathophysiology of sarcopenia and its metabolic repercussions. Therefore, knowing how organokines act is very important to know their impacts on age, disease prevention, and how they can be related to the prevention of muscle loss. 相似文献
100.
Teodor Paul Kacso Renata Zahu Alexandru Tirpe Elina Valeria Paslari Andreea Nuu Ioana Berindan-Neagoe 《International journal of molecular sciences》2022,23(17)
Long non-coding RNAs (lncRNA) have recently been identified as key regulators of oxidative stress in several malignancies. The level of reactive oxygen species (ROS) must be constantly regulated to maintain cancer cell proliferation and chemoresistance and to prevent apoptosis. This review will discuss how lncRNAs alter the ROS level in cancer cells. We will first describe the role of lncRNAs in the nuclear factor like 2 (Nrf-2) coordinated antioxidant response of cancer cells. Secondly, we show how lncRNAs can promote the Warburg effect in cancer cells, thus shifting the cancer cell’s “building blocks” towards molecules important in oxidative stress regulation. Lastly, we explain the role that lncRNAs play in ROS-induced cancer cell apoptosis and proliferation. 相似文献