Transporter protein genes are differentially expressed in Acidithiobacillus ferrooxidans LR maintained in contact with covellite

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Simultaneous Determination of Ba, Cr, Mo (Group 1), and Cu, Fe, Ni, and Pb (Group 2) in Commercial Fuel Ethanol by Graphite Furnace AAS

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Strontium zirconate heterogeneous catalyst for biodiesel production: Synthesis, characterization and catalytic activity evaluation

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Bioestimulante na promoção da brotação em estacas de raiz de amoreira-preta

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

On the development of the brown spider Loxosceles gaucho Gertsch (Araneae, Sicariidae): the nympho-imaginal period

Observations of the developmental biology of Loxosceles gaucho Gertsch, 1967, the brown spider of southeastern Brazil are scarce. The present study reports the method of individualized rearing of 18 populations of L. gaucho, kept in laboratory under varied diet conditions, and characterizes their nympho-imaginal period as well as factors related to their reproduction. Females built the first egg sac about 20 days after copulation and nymphs hatched 40 days after the laying date. Average offspring was 61.3 spiderlings and females usually built three to four successive egg sacs in a period of five to seven months. First nymphs initiated their predatory activity between the 5th and 8th days after hatching and the majority reached adulthood within six moults (range of five to eight) in approximately 15 to 17 months (male) and 15.5 to 18 months (female). The average sex ratio equaled 1.0:1.7 (male:female). The wide individual variability of this species intermoult intervals is herewith expressed by the intermoult rate, which was fairly uniform for both intra and interpopulations and gives a relevant aspect for a general idea of the life cycles of spiders.

Fibra solúvel e amido como fontes de carboidratos para terminação de novilhos em confinamento

Avaliou-se o efeito da utilização de duas fontes de carboidratos solúveis, amido ou fibra solúvel em detergente neutro, associadas a dois níveis de FDN, sobre o desempenho de novilhos de corte em confinamento na fase de terminação. Foram confinados 24 novilhos ½ Angus x ½ Nelore, com idade inicial de 18 meses e peso de 329 ± 24 kg. As quatro dietas foram calculadas para fornecer nível de PB suficiente para ganho diário de 1,4 kg. As dietas foram constituídas de 40% de silagem de milho e 60% de concentrado (grão de milho, polpa cítrica e casca de soja), além de minerais e uréia, arranjados de forma a promover nível alto de amido associado a dois níveis de FDN (48 e 39%) ou nível alto de fibra solúvel associado aos dois níveis de FDN. Observou-se que os animais alimentados com a dieta com maior nível de polpa cítrica (45%), com baixos teores de fibra solúvel e FDN, apresentaram consumo reduzido e, conseqüentemente, baixo ganho de peso e pior conversão alimentar. Entre as dietas com maior nível de FDN, verificou-se que os animais alimentados com fibra solúvel apresentaram o melhor ganho de peso (1,435 vs 1,262 kg/dia) e a melhor conversão alimentar (7,494 vs 8,651), mas não diferiram daqueles do tratamento com amido e baixo teor de FDN. Os resultados demonstraram que é possível alterar o desempenho animal manipulando a fonte e a concentração dos carboidratos solúveis.

Mass fractal characteristics of wet sonogels as determined by small-angle x-ray scattering and differential scanning calorimetry

Low density silica sonogels were prepared from acid sonohydrolysis of tetraethoxysilane. Wet gels were studied by small-angle x-ray scattering (SAXS) and differential scanning calorimetry (DSC). The DSC tests were carried out under a heating rate of 2 degrees C/min from -120 degrees C up to 30 degrees C. Aerogels were obtained by CO(2) supercritical extraction and characterized by nitrogen adsorption and SAXS. The DSC thermogram displays two distinct endothermic peaks. The first, a broad peak extending from about -80 degrees C up to practically 0 degrees C, was associated to the melting of ice nanocrystals with a crystal size distribution with pore diameter ranging from 1 or 2 nm up to about 60 nm, as estimated from Thomson's equation. The second, a sharp peak with onset temperature close to 0 degrees C, was attributed to the melting of macroscopic crystals. The DSC incremental nanopore volume distribution is in reasonable agreement with the incremental pore volume distribution of the aerogel as determined from nitrogen adsorption. No macroporosity was detected by nitrogen adsorption, probably because the adsorption method applies stress on the sample during measurement, leading to a underestimation of pore volume, or because often positive curvature of the solid surface is in aerogels, making the nitrogen condensation more difficult. According to the SAXS results, the solid network of the wet gels behaves as a mass fractal structure with mass fractal dimension D=2.20 +/- 0.01 in a characteristic length scale below xi=7.9 +/- 0.1 nm. The mass fractal characteristics of the wet gels have also been probed from DSC data by means of an earlier applied modeling for generation of a mass fractal from the incremental pore volume distribution curves. The results are shown to be in interesting agreement with the results from SAXS.

Debris perturbed by radiation pressure: relative velocities across circular orbits

In the present work we consider a dynamical system of mum size particles around the Earth subject to the effects of radiation pressure. Our main goal is to study the evolution of its relative velocity with respect to the co-planar circular orbits that it crosses. The particles were initially in a circular geostationary orbit, and the particles size were in the range between 1 and 100 mum. The radiation pressure produces variations in its eccentricity, resulting in a change in its orbital velocity. The results indicated the maximum linear momentum and kinetic energy increases as the particle size increases. For a particle of 1 mum the kinetic energy is approximately 1.56 x 10(-7) J and the momentum is 6.27 x 10(-11) kg m/s and for 100 mum the energy is approximately 1.82 x 10(-4) J and the momentum is 2.14 x 10(-6) kg m/s. (C) 2004 COSPAR. Published by Elsevier Ltd. All rights reserved.

Morphological characterization of follicle deviation in Nelore (Bos indicus) heifers and cows

Follicle diameter deviation is defined as the beginning of the differential change in growth rates between the largest and next largest follicles subsequent to wave emergence and is considered a key component of follicle selection. Follicle selection has been extensively studied in European breeds of cattle (Bos taurus) but has not been critically studied in Zebu breeds (Bos indicus). The objectives of the present study were to determine and compare the morphological characteristics of deviation associated with the first post-ovulatory wave (Wave 1) of the estrous cycle in Nelore heifers (n = 8) and nonlactating cows (n = 11). Beginning on the day of ovulation (day 0), the three largest follicles (F1-F3, respectively) were individually tracked every 12 h for 6 d using transrectal ultrasonography. In individual animals, deviation was determined graphically using visual inspection of the diameter profiles of F1, F2 and sometimes F3 (observed deviation) and mathematically using segmented regression analysis of the diameter differences between F1 and F2 or sometimes F3 (calculated deviation). Mean day of emergence of Wave 1 when F1 reached >3 rum (approximately 1 d after ovulation) and growth rate of F1 during deviation (approximately 1.4 mm/d) were not significantly different between heifers and cows. The results of determining the beginning of deviation within heifers and cows using the observed and calculated methods were not significantly different. Averaged over both methods, diameter deviation occurred 2.8 d after ovulation when F1 reached 5.7 mm in heifers, and 2.4 d after ovulation when F1 reached 6.1 mm in cows. In conclusion, the emergence of Wave 1 and growth rates and diameters of the future dominant follicles at the beginning of deviation were similar in Nelore heifers and nonlactating cows, regardless of the methods used to determine deviation. Relative to Holstein cattle, emergence of Wave 1 appeared to occur about 1 d later and diameter of the future dominant follicle at the beginning of deviation was about 2 turn smaller in Nelore. (C) 2004 Elsevier B.V. All rights reserved.

Spermatogenic cycle length and spermatogenic efficiency in the gerbil (Meriones unguiculatus)

The gerbil (Meriones unguiculatus) is a rodent native of the and regions of Mongolia and China. Because the gerbil can be easily bred in laboratory conditions, this species has been largely used as an experimental model in biomedical research. However, there is still little information concerning the testis structure and function in the gerbil. In this regard, we performed a detailed morphofunctional analysis of the gerbil testis and estimated the spermatogenic cycle length utilizing H-3-thymidine as a marker for germ cell progression during their evolution through the spermatogenic process. The stage frequencies of the XII stages characterized according to the acrosome formation and development were (I-XII) 13.8, 10.1, 8.1, 7.8, 4.0, 11.2, 7.5, 7.1, 5.9, 7.6, 8.1, and 8.9. The mean duration of each seminiferous epithelium cycle was determined to be 10.6 +/- 1.0 days and the total duration of spermatogenesis, based on 4.5 cycles, was approximately 47.5 days. The volume density of tubular and interstitial compartments was approximately 92% and 8%, respectively. Based on the volume occupied by seminiferous tubules in the testis and the tubular diameter, about 9 and 18 m of seminiferous tubules were found per testis and per gram of testis, respectively. Twelve primary spermatocytes were formed from each type A1 spermatogonia. The meiotic index was 2.8, indicating that 30% of cell loss occurs during meiosis. The number of Leydig and Sertoli cells per gram of the testis was 28 million and each Sertoli cell was able to support approximately 13 spermatids. The daily sperm production per gram of testis (spermatogenic efficiency) was 33 million. Taken together, these data indicate that, mainly due to the high seminiferous tubule volume density and Sertoli cell support capacity for germ cells, the gerbil presents high spermatogenic efficiency compared with other mammalian species already investigated. The data obtained in the present study might provide the basis for future research involving the reproductive biology in this species.

Progesterone upregulates GATA-1 on erythroid progenitors cells in liquid culture

Steroids hormones modify the hematological features of homozygous sickle cell disease, including the levels of fetal hemoglobin. We used semi-quantitative RT-PCR analysis of GATA-1, GATA-2, NF-E2, and gamma-globin mRNA levels in a two-phase liquid culture system of human adult erythroid cells in order to assay the effect of progesterone upon gene expression. The levels of expression of GATA-1 and gamma-globin mRNA were significantly increased in cells treated with progesterone compared to untreated cells (1.7- to 2.0-fold). Progesterone treatment did not produce any stimulatory effect upon GATA-2 and NF-E2 mRNA expression. Differences in the synthesis of HbF protein could not be detected by flow cytometry, although we observed a small difference in mean intensity fluorescence between cells treated and cells untreated with progesterone on days 7 and 9. Using anti-transferrin receptor and anti-glycophorin A antibodies, we verified that addition of progesterone did not cause any change in erythroid proliferation and differentiation. In conclusion, it is possible that the increased expression of gamma-globin mRNA after progesterone treatment observed in this study may be related to the increased GATA-1 mRNA expression. Interactions of the steroid receptors with the basal transcriptional machinery and with transcription factors might mediate their transcriptional effects. (C) 2002 Elsevier B.V. (USA).

Patients' Expectations Before and Evaluation After Dental Implant Therapy

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Effect of intraperitoneal or incisional bupivacaine on pain and the analgesic requirement after ovariohysterectomy in dogs

Objective To compare the effect of intraperitoneal (IP) or incisional (INC) bupivacaine on pain and the analgesic requirement after ovariohysterectomy in dogs.Study design Prospective, randomized clinical study.Animals Thirty female dogs undergoing ovariohysterectomy (OHE).Methods Dogs admitted for elective OHE were anesthetized with acepromazine, butorphanol, thiopental and halothane. Animals were randomly assigned to one of three groups (n = 10 per group). The treatments consisted of preincisional infiltration with saline solution (NaCl 0.9%) or bupivacaine with epinephrine and/or IP administration of the same solutions, as follows: INC and IP 0.9% NaCl (control group); INC 0.9% NaCl and IP bupivacaine (5 mg kg(-1), IP group); INC bupivacaine (1 mg kg(-1)) and IP 0.9% NaCl (INC group). Postoperative pain was evaluated by a blinded observer for 24 hours after extubation by means of a visual analog scale (VAS) and a numeric rating scale (NRS). Rescue analgesia (morphine, 0.5 mg kg(-1), IM) was administered if the VAS was > 5/10 or the NRS > 10/29.Results At 1 hour after anesthesia, VAS pain scores were [medians (interquartile range)]: 6.4 (3.1-7.9), 0.3 (0.0-2.6) and 0.0 (0.0-7.0) in control, IP and INC groups, respectively. VAS pain scores were lower in the IP compared to the control group. Over the first 24 hours, rescue analgesia was administered to 7/10, 5/10 and 3/10 dogs of the control, INC and IP groups, respectively. Total number of dogs given rescue analgesia over the first 24 hours did not differ significantly among groups.Conclusions and clinical relevance Intraperitoneal bupivacaine resulted in lower pain scores during the first hour of the postoperative period and there was a trend towards a decreased need for rescue analgesia after OHE in dogs.

Strong infrared spectral broadening in low-loss As-S chalcogenide suspended core microstructured optical fibers

We report the fabrication and characterization of the first guiding chalcogenide As(2)S(3) microstructured optical fibers (MOFs) with a suspended core. At 1.55 mu m, the measured losses are approximately 0.7 dB/m or 0.35 dB/m according to the MOF core size. The fibers have been designed to present a zero dispersion wavelength (ZDW) around 2 mu m. By pumping the fibers at 1.55 mu m, strong spectral broadenings are obtained in both 1.8 and 45-m-long fibers by using a picosecond fiber laser. (C) 2010 Optical Society of America

Effect of surface treatments on the resin bond to zirconium-based ceramic

Purpose: This study tested the hypothesis that the tribochemical silica coating on ceramic surfaces increases the bond strength of resin cement to a glass-infiltrated zirconium-based ceramic. Materials and Methods: Fifteen blocks of In-Ceram Zirconia from CEREC InLab (5 per group) and 15 composite blocks (Z-250) 5 mm x 5 mm x 4 mm were made. The ceramic surfaces were polished, and the blocks were divided into three groups: (1) airborne abrasion with 110-μm aluminum oxide particles; (2) Rocatec system, tribochemical silica coating; and (3) CoJet system, tribochemical silica coating. The ceramic blocks were cemented to the composite blocks using Panavia F according to the manufacturer's specifications. All samples were stored in 37°C distilled water for 7 days and later sectioned in two axes using a diamond disk under cooling to obtain specimens with a cross-sectional area of approximately 1 mm2 (n = 45). Each specimen was then attached with cyanoacrylate glue to an adapted device for the microtensile test, which was carried out on a universal testing machine. Results: The results were subjected to ANOVA and Tukey's test. Group 2 (23.0 ± 6.7 MPa) and group 3 (26.8 ± 7.4 MPa) showed greater bond strength than group 1 (15.1 ± 5.3 MPa). There was no significant difference between groups 2 and 3. All failures were in the adhesive zone. Conclusion: The hypothesis was confirmed - the tribochemical systems increased the bond strength between Panavia F and In-Ceram Zirconia.