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The brain aging process triggers cognitive function impairment, such as memory loss and compromised quality of life. Cognitive impairment is based on bioenergetic status, with reduced glucose uptake and metabolism in aged brains. Anaplerotic substrates are reported to promote mitochondrial ATP generation, having been tested in clinical trials for the treatment of neurological disorders and metabolic diseases. Objectives and Methods: To assess whether the improvement in oxidative capacity ameliorates cognitive function in adults (12 weeks), and aged (22-month-old) C57/6BJ mice, they received (1) a ketogenic diet, (2) a ketogenic diet supplemented with the anaplerotic substance, triheptanoin, or (3) a control diet for 12 weeks. Spontaneous alternation and time spent in a previously closed arm in the Y-maze test and time interacting with an unknown object in the novel object recognition test (NORT) were used to evaluate working memory. Acetylcholinesterase (AChE) activity in the prefrontal lobe, brain left hemisphere, and cerebellum was also evaluated. Glucose transporter 3 (GLUT3) expression in the prefrontal lobe was analyzed by western blotting. Results: The ketogenic diet (KD) reduced spontaneous alternation in aged mice, leading to lower AChE activity in the aged prefrontal lobe and cerebellum, and in the parieto-temporal-occipital lobe of adult mice. Furthermore, KD decreased GLUT3 protein expression in the frontal lobe of the adults. Discussion: Supplementation of KD with triheptanoin prevented memory impairment and showed similar values of AChE activity and GLUT3 expression compared to the controls. Our data suggest that triheptanoin has a potential role in the bioenergetic capacity of the brain, improving cognitive function. [ABSTRACT FROM AUTHOR]

This study reports the synthesis of hybrid nanostructures composed of cerium dioxide and microcrystalline cellulose prepared by the microwave-assisted hydrothermal route under distinct temperature and pH values. Their structural, morphological and spectroscopic behaviors were investigated by X-Rays Diffraction, Field Emission Gun Scanning Electron Microscopy, High-Resolution Transmission Electron Microscopy, and Fourier-Transform Infrared, Ultraviolet–Visible, Raman and Positron Annihilation Lifetime spectroscopies to evaluate the presence of structural defects and their correlation with the underlying mechanism regarding the biocide activity of the studied material. The samples showed mean crystallite sizes around 10 nm, characterizing the formation of quantum dots unevenly distributed along the cellulose surface with a certain agglomeration degree. The samples presented the characteristic Ce–O vibration close to 450 cm−1 and a second-order mode around 1050 cm−1, which is indicative of distribution of localized energetic levels originated from defective species, essential in the scavenging of reactive oxygen species. Positron spectroscopic studies showed first and second lifetime components ranging between 202–223 ps and 360–373 ps, respectively, revealing the presence of two distinct defective oxygen species, in addition to an increment in the concentration of Ce3+-oxygen vacancy associates as a function of temperature. Therefore, we have successfully synthesized hybrid nanoceria structures with potential multifunctional therapeutic properties to be further evaluated against the COVID-19. [ABSTRACT FROM AUTHOR]

This paper is a proposal to embed tree-shaped vasculatures in a wall designed such that the wall withstands without excessive hot spots and peak stresses the intense heating and pressure that impinge on it. The vasculature is a quilt of square-shaped panels, each panel having a tree vasculature that connects the center with the perimeter. The vascular designs for volumetric cooling can be complemented by the shaping and distributing of channels for maximum strength and thermal performance at the same time. Numerical simulations of heat flow and thermal stresses in three directions show that it is possible to determine the optimal geometric features of configurations with radial channels and trees with radial and one level of bifurcations. The global performance is evaluated in terms of the overall thermal resistance and peak von Mises stresses. The dendritic design is superior under the studied thermal condition. [ABSTRACT FROM AUTHOR]

The search for the true ground state of the dense matter remains open since Bodmer, Terazawa and others raised the possibility of stable quark matter, boosted by Witten's strange matter hypothesis in 1984. Within this proposal, the strange matter is assumed to be composed of s t r a n g e quarks in addition to the usual u p s and d o w n s, having an energy per baryon lower than the strangeless counterpart, and even lower than that of nuclear matter. In this sense, neutron stars should actually be strange stars. Later work showed that a paired, symmetric in flavor, color-flavor locked (CFL) state would be preferred to the one without any pairing for a wide range of the parameters (gap Δ , strange quark mass m s and bag constant B). We use an approximate, yet very accurate, CFL equation-of-state (EoS) that generalizes the MIT bag model to obtain two families of exact solutions for the static Einstein Field Equations (EFE) constructing families of anisotropic compact relativistic objects. In this fashion, we provide exact useful solutions directly connected with microphysics. [ABSTRACT FROM AUTHOR]

Here we show that the production and use of heating on an area must be distributed in clusters organized such that the losses associated with centers of production are balanced by the losses associated with distribution lines. The energy needs increase in time because the population density and the individual need increase. We consider only the increase in the individual need in time. We illustrate the 'distributed energy systems' concept with the production and distribution of hot water on an area. Four classes of designs are analyzed and compared: (0) individual, i.e., one water heater for one user, (r) radial, i.e., N users supplied via radial pipes from a central heater, (2) dendritic network constructed by pairing N users around a central heating, and (4) dendritic network constructed by quadrupling the elemental areas occupied by the users. We show that there is an optimal cluster size (N) as a tradeoff between central losses and distributed losses. We also discover that several distinct (abrupt) design 'transitions' must exist: the recommended design changes through designs 0, r, 2, and 4, as the amount of water used by each individual increases in time with the standard of living. [ABSTRACT FROM AUTHOR]

The search for the true ground state of dense matter has remained open since Edward Witten proposed the strange matter hypothesis in 1984. In this hypothesis, the strange matter is assumed to be composed of u, d, and s quarks, having an energy per baryon lower than that of quark matter (only u and d), and even lower than that of the nuclear matter. In this sense, neutron stars would be strange stars. Later work showed that a color‐flavor‐locked (CFL) state would be preferred to the one without any pairing for a wide range of the parameters (gap Δ, strange quark mass ms, and bag constant B). We use an approximate, yet very accurate, CFL equation of state (EoS) to obtain exact solutions for the static Einstein field equations that describe a compact relativistic object, providing the first solution directly connected with microphysics. [ABSTRACT FROM AUTHOR]

Purulent vaginal discharge (PVD) is a common uterine disease in dairy cattle that has negative effects on reproductive performance. Reproductive management programs that synchronize ovulation use gonadotropin-releasing hormone (GnRH) to induce ovulation and prostaglandin F2α (PGF2α) to induce luteolysis. The objectives of this study were to evaluate ovarian response to treatment with GnRH and the odds of bearing a corpus luteum or being inseminated in dairy cows with or without PVD. Another objective was to determine the hazard of insemination after administration of PGF2α in dairy cows with or without PVD. Primiparous (n = 291) and multiparous (n = 402) cows were evaluated for PVD using a Metricheck device at 46 ± 3 and 35 ± 3 days in milk (DIM) (study day 0), respectively. On study day 14, primiparous (n = 107) and multiparous (n = 197) cows were treated with GnRH and subsequent ovulation was recorded. Primiparous (n = 178) and multiparous (n = 368) cows not inseminated by study day 21 were administered PGF2α and response to PGF2α treatment was determined by detection of estrus. Furthermore, cows were categorized by the presence of a CL or being inseminated by study days 14, 21, and 35. Overall prevalence of PVD was 28.5% and 13.4% for primiparous and multiparous cows, respectively. Projected 305-d milk yield was less (P < 0.01) in PVD+ multiparous cows compared with PVD- multiparous cows, however, no (P = 0.26) difference was detected between primiparous PVD+ and PVD- cows. Ovulatory response to GnRH treatment was 51.8% and 47.8% for primiparous and multiparous cows, respectively. Primiparous PVD- cows tended (P = 0.06) to be less likely to ovulate to GnRH than primiparous PVD+ cows, whereas multiparous PVD+ cows were less (P = 0.04) likely to ovulate to GnRH than PVD- multiparous cows. The odds of bearing a corpus luteum or being inseminated by study days 14, 21, or 35 was not associated with PVD in primiparous cows. In contrast, the odds of bearing a corpus luteum or being inseminated by study days 14 and 21 was (P ≤ 0.03) associated with PVD in multiparous cows, but not (P = 0.11) on study day 35. Hazard of insemination after PGF2α was not (P ≥ 0.38) associated with PVD in primiparous or multiparous cows. Purulent vaginal discharge is associated with response to treatment with GnRH in dairy cattle. Purulent vaginal discharge might negatively affect reproductive management programs that use GnRH to induce ovulation. [ABSTRACT FROM AUTHOR]

Background Electrical impedance spectroscopy ( EIS) is a noninvasive diagnostic technique that measures tissue impedance. Objectives To evaluate the effect of adding an EIS measurement at baseline to suspicious melanocytic lesions undergoing routine short-term sequential digital dermoscopy imaging ( SDDI). Methods Patients presented with suspicious melanocytic lesions that were eligible for short-term SDDI (with no clear feature of melanoma on dermoscopy). EIS measurement was performed at the first visit following dermoscopic photography. Normally, an EIS score of ≥ 4 is considered positive; however, this protocol investigated a higher cut-off in combination with SDDI. When the EIS score was ≥ 7 the lesion was excised immediately owing to the high risk of melanoma. Lesions with a score < 7 were monitored with standard SDDI over a 3-month period. Results From a total of 160 lesions analysed, 128 of 154 benign lesions received an EIS score of 0-6, giving a specificity of the EIS method for the diagnosis of melanoma of 83·1% [95% confidence interval ( CI) 76·3-88·7]. Five of the six melanomas found in this study had an EIS score ≥ 7, with a sensitivity for melanoma diagnosis of 83·3% (95% CI 35·9-99·6). When EIS 0-6 lesions were subsequently followed up with SDDI, one additional melanoma was detected (EIS = 6) giving a sensitivity for the diagnosis of melanoma overall of 100% (95% CI 54·1-100; six of six malignant melanomas excised) and a specificity of 69·5% (95% CI 61·5-76·6; 107 of 154 benign lesions not excised). Conclusions If utilizing a protocol where an EIS score ≤ 3 requires no SDDI and ≥ 7 requires immediate excision, it reduced the need for SDDI by 46·9% ( n = 75/160; 95% CI 39·0-54·9). [ABSTRACT FROM AUTHOR]

This paper presents generalized dynamic models for Marx derived multilevel half-bridge bipolar modulators. This high-voltage topology uses modular Marx multilevel converter diode ( \textM^\mathrm 3 CD) cells to generate positive and negative (bipolar) pulses or unipolar (positive or negative voltage pulses). The developed models are tested in transient studies of pulse voltages and currents in the load. Simulation and experimental results are presented and compared. [ABSTRACT FROM PUBLISHER]

Until recently, you had the idea that standardized procedures and attitudes were sufficient for success in business. However, this idea is in the transformation process. In this context, the decision model effectuation been proposed as an alternative to the classical decision model based on the principle of causality. The conceptual basis that allows the operationalization of the concept of effectuation is: (a) the idea of tolerable loss, rather than expected returns, (b) strategic alliances and pre - agreed, rather than competitive analysis and (c) the commitments operating contingencies, rather than pre-existing knowledge. By using processes under the effectuation logic to start a business, the entrepreneur can build different types of companies in completely different industries. Thus, the decision model effectuation emerges as an alternative model for the analysis of business creation, often being more appropriate to the current context. [ABSTRACT FROM AUTHOR]

This paper shows how to use modular Marx multilevel converter diode ( \textM^3 CD) modules to apply unipolar or bipolar high-voltage pulses for pulsed power applications. The \textM^3 CD cells allow the assembly of a multilevel converter without needing complex algorithms and parameter measurement to balance the capacitor voltages. This paper also explains how to supply all the modular cells in order to ensure galvanic isolation between control circuits and power circuits. The experimental results for a generator with seven levels, and unipolar and bipolar pulses into resistive, inductive, and capacitive loads are presented. [ABSTRACT FROM AUTHOR]

The objectives of the experiments were to compare ovarian responses, pregnancy per artificial insemination, and pattern of insemination of 2 estrus detectionbased presynchronization protocols before first artificial insemination (AI) during heat stress. In experiment 1, primiparous lactating dairy cows (n = 1,358) from 3 dairies were assigned randomly to 2 treatments at 60 ± 3 (±SD) DIM (study d 0): (1) treatment with 100 μg of GnRH on study d 0 (Gpresynch), or (2) no treatment on study d 0 (control). In experiment 2, multiparous lactating dairy cows (n = 1,971) from 3 dairies were assigned randomly to 2 treatments at 49 ± 3 (±SD) DIM (study d 0), similar to experiment 1. In both experiments, PGF2α injections were administered 14 d apart starting on study d 7 for all cows. Cows not inseminated after detection of estrus were submitted to a timed artificial insemination protocol at study d 35. In a subgroup of cows from 2 dairies, concentrations of progesterone were determined from blood samples collected on study d 0 and 7. Furthermore, ovaries were examined by ultrasonography on study d -14, 0, and 7 to determine cyclic status and ovulation in response to GnRH treatment. In experiment 1, progesterone concentration was not different on d 0, but progesterone was increased for Gpresynch compared with control cows on study d 7 (3.6 ± 0.3 vs. 2.7 ± 0.4 ng/mL), respectively. Ovulation risk from study d 0 to 7 was increased for Gpresynch compared with control (50.6 vs. 15.2%). Control cows were inseminated at a faster rate than Gpresynch cows [adjusted hazard ratio (AHR) = 0.89, 95% confidence interval = 0.80 to 1.00], and the interaction between treatment and dairy affected pregnancy per artificial insemination at 36 and 94 d post-artificial insemination. In experiment 2, concentrations of progesterone did not differ on study d 0 or 7, despite ovulation risk from study d 0 to 7 being greater in Gpresynch than control cows (46.9 vs. 23.8%). The interaction between treatment and dairy affected hazard of insemination with Gpresynch cows from dairy 1 (AHR = 1.21; 1.05 to 1.41) being inseminated faster than control cows. Hazard of pregnancy was affected by treatment because Gpresynch cows became pregnant at a faster rate than control cows (AHR = 1.25; 1.04 to 1.50). In conclusion, GnRH-based presynchronization protocols initiated before the end of the voluntary waiting period may have benefits in reproductive efficiency of estrus detection-based programs during heat stress. In addition, treatment with GnRH decreased the prevalence of anovular cows at the initiation of PGF2α injections. [ABSTRACT FROM AUTHOR]

The Fusarium oxysporum species complex ( FOSC) causes disease in plants and animals, but is also widely dispersed in natural ecosystems without evidence of disease. The present study screened a population representing natural ecosystems across the Australian continent for the putative effector genes pisatin demethylase 1 ( PDA1), pectate lyase ( pelD), secreted gene expression ( SGE1) and secreted in xylem ( SIX). The genes pelD and SGE1 were prevalent in the natural isolates, PDA1 was present at an intermediate level, whereas SIX genes were detected at low levels. Phylogenies of these putative effector genes were compared to the EF-1α species phylogeny to determine the likely modes of gene transmission: vertical gene transfer ( VGT) and horizontal gene transfer ( HGT). There was evidence of both modes of gene transmission within the F. oxysporum isolates. PDA1, pelD and SGE1 were likely to be only vertically inherited, whereas the SIX genes had evidence for both VGT and HGT. The phylogenetic relationships of SIX genes in isolates from natural ecosystems and formae speciales from agro-ecosystems were also established. These findings have important implications for the evolution of effectors in the FOSC. [ABSTRACT FROM AUTHOR]

In this study, a waste-based magnetic activated carbon (MAC) was used for the first time in a continuous-flow stirred tank reactor (CSTR). The aim was to evaluate the dynamic removal of diclofenac (DCF) from water and wastewater. Firstly, the breakthrough curves corresponding to DCF adsorption from distilled water at different feed flow rates and doses of MAC were determined. After selecting the most favourable conditions, namely 0.18 h L−1 flow rate and 400 mg L−1 of MAC, the effect of different aqueous matrices was studied, with the breakthrough curves evidencing a performance decline in wastewater in comparison with distilled water. Finally, the exhausted MAC was magnetically recovered, regenerated by microwave-assisted heating and applied in two subsequent adsorption cycles. The regeneration studies pointed to a decrease of the specific surface area and an improvement of the magnetic retrievability of MAC. After the first regeneration step, just mild effects were observed in the dynamic adsorptive performance of MAC. However, after a second regeneration step, the performance declined ca. 50%. Overall, the results highlight the feasibility of producing waste-based magnetic composites that simultaneously combine high adsorption efficiency under dynamic operation in a CSTR, with easy retrievability and successful one-stage regeneration for further reutilization. [Display omitted] • Diclofenac (DCF) adsorption by waste-based magnetic activated carbon (MAC) was aimed. • Adsorptive performance was evaluated in a continuous stirred tank reactor (CSTR). • Most favourable flow rate and MAC dose for DCF adsorption from water were selected. • Under such conditions but from wastewater, matrix effects affected DCF adsorption. • Regenerated MAC by microwave heating (1 step) kept its CSTR adsorptive performance. [ABSTRACT FROM AUTHOR]

A putative role of the brain-derived neurotrophic factor (BDNF) in epilepsy has emerged from in vitro and animal models, but few studies have analyzed human samples. We assessed the BDNF expression of transcripts with exons I (BDNFI), II (BDNFII), IV (BDNFIV) and VI (BDNFVI) and methylation levels of promoters 4 and 6 in the hippocampi of patients with pharmaco-resistant temporal lobe epilepsy (TLE) ( n = 24). Hippocampal sclerosis (HS) and pre-surgical pharmacological treatment were considered as clinical independent variables. A statistical significant increase for the BDNFVI ( p < 0.05) was observed in TLE patients compared to the autopsy control group ( n = 8). BDNFVI was also increased in anxiety/depression TLE ( N = 4) when compared to autopsies or to the remaining group of patients ( p < 0.05). In contrast, the use of the antiepileptic drug Topiramate (TPM) ( N = 3) was associated to a decrease in BDNFVI expression ( p < 0.05) when compared to the remaining group of patients. Methylation levels at the BDNF promoters 4 and 6 were similar between TLE and autopsies and in relation to the use of either Sertraline (SRT) or TPM. These results suggest an up-regulated expression of a specific BDNF transcript in patients with TLE, an effect that seems to be dependent on the use of specific drugs. [ABSTRACT FROM AUTHOR]

The objective of this study was to assess the relationship between the animal welfare conditions evaluated through the supply chain and pork quality variation. A total of 4,680 pigs from 12 farms--5 animal welfare improved raising system (AWIRS) and 7 conventional raising system (CON) farms--were assessed from farm to slaughter through a comprehensive audit protocol merging the European Welfare Quality, the Canadian Animal Care Assessment, and American Meat Institute audit guide criteria. At the abattoir, a subsample of 1,440 pigs (120 pigs/farm) was randomly chosen out of 24 loads (2 farms per wk) transported by 2 drivers (driver A and driver B) for the assessment of stunning effectiveness, carcass bruises, blood lactate levels, and meat quality traits. Meat quality was assessed in the longissimus lumborum (LL) muscle 24 h postmortem by measuring ultimate pH (pHu), color (L*, a*, and b*), and drip loss. Data were analyzed by the MIXED, GLIMMIX, and NAPAR1WAY procedures of SAS. Spearman correlations were calculated to determine the relationship between audit scores and meat quality traits. Better animal welfare conditions, as showed by greater final scores for good housing (GHo; P = 0.001) and good health (P = 0.006) principles, were recorded at AWIRS farms. Pigs from AWIRS farms handled by driver B displayed a greater percentage of turning back (P = 0.01) and slips (P < 0.001) during unloading and a greater (P = 0.02) frequency of falls in the stunning chute. A greater (P = 0.02) reluctance to move at loading was found in CON pigs loaded by driver A compared with driver B, whereas a greater (P < 0.001) reluctance to move was found in these pigs at unloading when they were unloaded by driver B. Drip loss was higher (P = 0.003) and pale, soft, and exudative pork percentage was greater (P < 0.001) in the LL muscle of the heavier AWIRS pigs. The GHO principle was best correlated with pHu (r = -0.75, P = 0.01) and Minolta L* value (r = 0.87, P < 0.001) of the LL muscle. Overall, drip loss variation in the LL muscle was correlated with the frequency of slips at unloading (r = 0.63, P = 0.001) and in the restrainer area (r = 0.74, P < 0.001). The results of this study showed that the quality of the raising system and truck driver skills as assessed by animal welfare audit protocols are important sources of variation in the behavioral response of pigs to preslaughter handling and may affect pork quality variation. However, the different live weight between CON and AWIRS pigs may have biased the meat quality results in this study. [ABSTRACT FROM AUTHOR]

Stylogaster Macquart, 1835 has been unknown in the fossil record until now, the only fossil conopid genus being Palaeomyopa Meulnier, 1912. Two Stylogaster specimens in amber from the American Museum of Natural History collection were studied and are described here. Both specimens, male and female, belong to a new species, S. grimaldii sp. nov., that is probably basal to at least the New World species with a short ocellar triangle. Photos and drawings of the new species are provided. The relationship with other Stylogaster species and ancient distributional patterns are briefly discussed. [ABSTRACT FROM AUTHOR]

The present work approaches the theme organizational culture and organizational climate in a Federal Institute of Education's campus situated in a Brazilian northeast state, being product of a research that began in these questions: How does approach the organizational culture and the organizational climate in Federal Institute of Education? How does the Federal Institute of Education's organizational culture influence the organizational climate? Methodologically, this research is a quantitative research, with a functionalist bias, that used a lot of statistic tests, as clusters analysis, discriminant analysis, T-Student test, Pearson correlation analysis, Spearman correlation analysis and canonic correlation analysis. This work looked for accomplishing a sample with all individuals in a Federal Institute of Education's campus and the surveys were answered by 92% of the public servants (57 of the 62 total public servants). The data collection was accomplished by structured and self-filled out survey sent to the answers and returned to the researchers by e-mail. The text concluded that there was a big influence of the organizational culture over the organizational climate, proving empirically what is defended by a lot of researchers [ABSTRACT FROM AUTHOR]

Gellan gum is a polysaccharide polymer used in the pharmaceutical and food industries due to its gelling ability. In this work, it was intended to innovatively develop a new chromatographic matrix based on this polymer. This new chromatographic approach takes into account properties like the porosity and hydrophilicity of gellan gels as well as its anionic nature in order to study the interactions established with three model proteins. The versatility of interactions of this new matrix was also tested applying hydrophobic interaction chromatography conditions. Binding/elution studies with three model proteins were performed using gellan cross-linked with calcium. These studies established the elution patterns of the studied biomolecules, separating simple mixtures of proteins with different interaction profiles. Finally, it was made experiments with nucleic acids in hydrophobic conditions with the same purposes, proving the versatility of interactions in the gellan matrix. The structure of the formulation applied in the chromatographic steps was evaluated by confocal laser microscopy. This technique showed the microscopic organization of the gels correlating it with its macroscopic porosity and permeability. Due to the necessity of the presence of calcium in the chemical environment of the stationary phase it was studied the stability that 3 different ions (calcium, copper and zinc) conferred to the matrix. Of the three studied ions it was copper who gave the biggest stability to the matrix. These preliminary results show a new potential application of gellan gum as a chromatography matrix, taking advantage of its natural charge without the necessity of functionalizing it with specific ligands. [ABSTRACT FROM AUTHOR]

Kidney transplantation in children has shown steady improvement in graft survival outcome over the last decades. Using data obtained from the transplantation registry of our center between 1984 and 2012, we assessed the independent determinants of graft failure using the Cox proportional hazards regression. Altogether, 128 recipients younger than 18 years of age at the time of kidney transplantation and who had >3 months graft survival were studied. During 9.95 years of medium follow-up, 27 censored graft failures occurred. Censored graft survival rates at 5, 10, 15, and 20 years post-transplantation were 93%, 82%, 70%, and 63%, respectively. Studied factors included recipient and donor age, recipient gender, dialysis vintage, donor/recipient cytomegalovirus (CMV) serology, panel-reactive antibody percentage, human leukocyte antigen mismatching, previous transplantation number, donor type (deceased vs living donation), cold ischemia time, induction therapy with antithymocyte globulin, occurrence of acute tubular necrosis, and development of acute rejection. Using univariate analysis, the significant predictors for graft-censored failure were adult donor (P < .001), recipient age (P = .035), human leukocyte antigen mismatching (P = .025), antithymocyte globulin induction (P = .03), and development of acute rejection (P < .001). Two factors independently predicted graft-censored failure in multivariate analysis. The odds ratios for graft failure in patients with acute rejection and in children who received an organ of an adult were 3.744 and 4.962, respectively. Pediatric recipients should receive the first priority for allografts from pediatric donors and acute rejection should be meticulously prevented. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effects of ractopamine supplementation, castration method, and their interaction on the behav-ioral and physiological response to preslaughter stress and carcass and meat quality of 2 Piétrain genotypes. A total of 1,488 male pigs (115 ± 5 kg BW) were dis-tributed according to a 2 * 2 x 2 factorial arrangement of treatments. The first factor was ractopamine supple-mentation with 2 groups of pigs (376 and 380 pigs each) receiving 7.5 mg/kg of ractopamine (RAC) or not (NRAC) in their diet during the last 28 d of the finish-ing period. The second factor was castration method, with 744 surgical castrates (SC) and 744 immunized males (IM), and the third factor was the genotype with 2 crossbreeds containing 50% (genotype A, GA; n = 744) or 25% (genotype B, GB; n = 744) Piétrain genet-ics. Surgical castration took place at 2 d of age, whereas immunization against gonadotropin-releasing factor (GnRF) was performed through 2 subcutaneous injec-tions of GnRF analog (Improvest, 2 mL) at 10 and 4 wk before slaughter. At loading more vocal stimulation was needed by the handler to drive GB pigs forward through the farm alley (P = 0.01) and RAC-fed GB pigs through the ramp (P = 0.02). Feeding RAC to IM increased the number of fights in lairage compared with SC (P = 0.03). Feeding RAC shortened fighting bouts compared with NRAC pigs (P = 0.05). The SC-GA pigs showed a greater gastrointestinal tract temperature dur-ing unloading (P = 0.05) and lairage time (P = 0.03). Blood creatine kinase (CK) concentrations were greater (P = 0.04) in SC compared with IM, and no difference was found in the concentrations of stress hormones in urine collected postmortem. Dressing yield was greater (P = 0.01) in RAC and SC-GB pigs. Carcasses from RAC pigs and IM were leaner than those from NRAC and SC pigs (P < 0.001 and P = 0.002, respectively). Feeding RAC to IM increased drip loss in the LM (P = 0.05). Warner-Bratzler shear force values were slightly greater in the LM from RAC-GB pigs and from IM compared with SC (P = 0.01 and P < 0.001, respec-tively) and in the semimembranosus muscle of RAC pigs (P = 0.006). In conclusion, immunization against GnRF more than the use of Piétrain genotypes appears to be a viable alternative to the use of ractopamine, as it seems to promote production of lean carcasses without compromising animal welfare and pork quality. [ABSTRACT FROM AUTHOR]

From a bibliographic research, this text shows, theoretically, by phenomenological and ontological ways, how the main ideas of Fourier's Utopian Socialism are present in principles of Solidarity Economy. The contemporary society's socioeconomic situation, based in consumerism and competitiveness, has created constraints, both for the capitalist economy and for most individuals. It is in times of crisis that Solidarity Economy appears as answer to inequalities and injustices inherent to capitalist system, focusing beyond the economy dimension, the social and environmental spheres. This not fragmented trend of life was thought in the past and is occurring - though in a limited way - nowadays. To show this understanding, throughout the work are recovered features of Fourier's thought that, today, appear strongly linked to the construct of Solidarity Economy. The realized exercise shows the vitality of the utopian socialism' ideals in the present. [ABSTRACT FROM AUTHOR]

The immune defence against Mycobacterium tuberculosis is complex and involves multiple interacting cells. Studies in subjects with polymorphisms in genes for IFN or its receptor gene evaluate their relationship with mycobacterium infections. The purpose of this study was to analyze the evidence of the effect of polymorphism +874 A/T from interferon-γ on the occurrence of tuberculosis. We performed a meta-analysis of studies published between June 2002 and April 2012. The articles analyzed assessed the relationship between the polymorphism +874 A/T and the development of tuberculosis. The meta-analysis was performed with a random effect model, considering the heterogeneity among studies. Genotype TT showed a protective effect (OR, 0.77; 95% CI = 0.67-0.88) while genotype AA may be associated with increased susceptibility to developing tuberculosis (OR, 1.51; 95% CI = 1.38-1.65). In relation to alleles, we can verify that the A allele is related to the development of tuberculosis (OR, 1.56; 95% CI = 1.42-1.71). This information reinforces the importance of host genetics in the development of infectious diseases. Studies in this area can result in the promotion of new and more accurate genetic markers. [ABSTRACT FROM AUTHOR]

Abstract: To better understand the impacts posed by soil contamination to aquatic ecosystems it is crucial to characterise the links between ecotoxicity, chemical availability and geochemical reactivity of potentially toxic elements (PTE’s) in soils. We evaluated the adverse effects of water extracts obtained from soils contaminated by chemical industry and mining, using a test battery including organisms from different trophic levels (bacteria, algae and daphnids). These tests provided a quick assessment of the ecotoxicity of soils with respect to possible adverse effects on aquatic organisms although the ecotoxicological responses could be related to the solubility of PTE’s only to a limited extent. The analysis of results of bioassays together with the chemical characterisation of water extracts provided additional relevant insight into the role of conductivity, pH, Al, Fe, and Mn of soil extracts on toxicity to organisms. Furthermore, an important conclusion of this study was that the toxicity of extracts to the aquatic organisms could also be related to the soil properties (pH, Org C and Feox) and to the reactivity of PTE’s in soils which in fact control the soluble fraction of the contaminants. The combined assessment of ecotoxicity in water fractions, solubility and geochemical reactivity of PTE’s in soils provided a more comprehensive understanding of the bioavailability of inorganic contaminants than ecotoxicological or chemical studies alone and can therefore be most useful for environmental risks assessment of contaminated soils. [Copyright &y& Elsevier]

This study constitutes an effort to assess the relevant issues which should be addressed in order to adapt models currently available in the literature to predict final particle distribution resulting from radial centrifugal casting (CC) of particle-reinforced metal-matrix functionally graded composites (FGM) to the conditions prevailing in longitudinal CC. As such, a comprehensive review of a set of those models is performed, in order to ascertain the methodologies, the physical assumptions made, and the inherent limitations in applicability, so as to clearly identify the main deviations from the physical conditions prevailing during longitudinal CC. That review is then complemented by evidence of phenomena observed in longitudinally centrifuged FGM composites which are not in accordance with the physical assumptions admitted by the examined models, thus illustrating some of the issues which must be catered for in any successful effort to establish an adequate model for longitudinal CC. [ABSTRACT FROM AUTHOR]

This paper describes an electro-mechanical auto-calibration technique for use in capacitive MEMS accelerometers. Auto-calibration is achieved using the combined information derived from an initial measurement of the resonance frequency and the measurement of the pull-in voltages during device operation, with an estimation of process-induced variations in device dimensions from layout and deviations in material properties from the known nominal value. An experiment-based analytical model is used to compute the required electrostatic forces required to simulate external accelerations allowing the electro-mechanical calibration of the accelerometer. Measurements on fabricated devices confirm the validity of the proposed technique and electro-mechanical calibration is experimentally demonstrated. [ABSTRACT FROM AUTHOR]

Abstract: This investigation addressed the processing of ultrafine tailings (slimes) from an iron ore concentrator via reverse cationic flotation to produce pellet feed fines, despite the traditional view that ultrafine particles do not float. Following size analyses, chemical and mineralogical characterisation, desliming and flotation tests were performed aiming at verifying the flotation behaviour of the slimes. Different dosages of collector and depressant were used. The promising results of the laboratory scale tests led to carrying out pilot scale tests with the currently produced slimes, and the slimes that will be generated in the future, after the commissioning of the mining company’s expansion project. It was observed that a reverse cationic column flotation process, using high depressant dosage, was selective, yielding high grade concentrates with low impurity content at high levels of iron recovery, approximately 60% mass recovery and 80% metallic recovery in the flotation stage. Excellent valuable product grade (less than 1% silica) and reject product grade (approximately 12% iron) were achieved, resulting in high selectivity levels. The overall mass recovery reached 20%. [ABSTRACT FROM AUTHOR]

Aims: To evaluate the sensitivity and specificity of polyclonal and monoclonal antibodies (Mabs) against intimin in the detection of enteropathogenic and enterohaemorrhagic Escherichia coli isolates using immunoblotting. Methods and Results: Polyclonal and Mabs against the intimin-conserved region were raised, and their reactivities were compared in enteropathogenic E. coli (EPEC) and enterohaemorrhagic E. coli (EHEC) isolates using immunoblotting analysis. In comparison with rat antiserum, rabbit anti-intimin IgG-enriched fraction had a stronger recognition pattern to a wide spectrum of intimin types in different EPEC and EHEC serotypes. On the other hand, murine monoclonal IgG2b specific to intimin, with dissociation constant of 1·3 × 10−8 mol l−1, failed in the detection of some of these isolates. Conclusion: All employed antibodies showed 100% specificity, not reacting with any of the eae-negative isolates. The sensitivity range was according to the employed antisera, and 97% for rabbit anti-intimin IgG-enriched fraction, followed by 92% and 78% sensitivity with rat antisera and Mab. Significance and Impact of the Study: The rabbit anti-intimin IgG-enriched fraction in immunoblotting analysis is a useful tool for EPEC and EHEC diagnoses. [ABSTRACT FROM AUTHOR]

Background: Sexual and reproductive health indicators and behaviors may occur differently between sex and according to sexual orientation. In addition, there is a lack of studies that consider sexual orientation and approach young adults in Brazil. Objective: To analyze sexual and reproductive health indicators of young Brazilian adults and their differences according to sex and sexual orientation. Methods: Cross-sectional study with 2,063 young adults, undergraduate students from a public university who responded to the online survey. We estimated the prevalence of sexual and reproductive health indicators, desire or not to have children, report of pregnancy and feeling about the pregnancy state), according to sex (male and female) and sexual orientation (heterosexual, bisexual, homosexual). Differences between prevalence were assessed using Pearson’s chi-square test. Results: Among heterosexuals, condoms were the contraceptive method most used by men (90.6%) and women (75.5%). Women used double protection (53.5%) and had a fixed sexual partner (67.8%) in a greater proportion. Men, on the other hand, maintain the practice of casual relationships more frequently (70.5%) and 43.2% have already had unprotected casual relationships. Among bisexuals, condoms were the method most used by men (97.7%) and women (85.4%). In this group, 51% of women use double protection and have a steady partner (62.2%). Among homosexuals, 99.1% of gays and 46.1% of lesbians used condoms at the last sexual intercourse and 46.1% of lesbians used hormonal methods. Also, 28.8% of gays have already had an STI, a higher rate than among heterosexuals. Conclusions: There are important differences in sexual and reproductive behaviors between genders and according to the sexual orientation of young people, such as greater vulnerability to STIs among gays and lesbians, and medicalization around the female body, highlighted by the permanence of questionable practices among lesbians. Key messages: • Gender issues could also explain the differences found between men and women. • Differences between the sexes are also present when evaluating the use of protection against STIs or unplanned pregnancies. [ABSTRACT FROM AUTHOR]

Covering <0·1% of the ocean’s surface, coral reefs harbour about one-third of all marine fishes or c. 5000 species. Allopatry (geographic isolation) is believed to be the primary mode of speciation, yet few biogeographic barriers exist between reefs, and most reef fishes have a pelagic larval stage capable of extensive dispersal. Under these circumstances, why are there so many species of reef fishes? Since most biogeographic barriers in the oceans are either spatially or temporally permeable on a relatively short time frame, the requirement of isolation during allopatric speciation is hard to satisfy. Evidence from empirical and theoretical studies, the biological characteristics of coral reefs, and a reanalysis of biogeographic barriers indicate that sympatric speciation is possible but not common at small spatial scales and that parapatric speciation is a common (and probably the prevalent) mode of diversification in coral-reef fishes. Regardless of the speciation mode, previous hypotheses of accelerated diversification in the Pleistocene due to sea level fluctuations are not supported by phylogenetic analyses. Recent developments in the area of comparative genomics can fuel a new revolution in the way marine speciation is studied. [ABSTRACT FROM AUTHOR]

Aim To understand why and when areas of endemism (provinces) of the tropical Atlantic Ocean were formed, how they relate to each other, and what processes have contributed to faunal enrichment. Location Atlantic Ocean. Methods The distributions of 2605 species of reef fishes were compiled for 25 areas of the Atlantic and southern Africa. Maximum-parsimony and distance analyses were employed to investigate biogeographical relationships among those areas. A collection of 26 phylogenies of various Atlantic reef fish taxa was used to assess patterns of origin and diversification relative to evolutionary scenarios based on spatio-temporal sequences of species splitting produced by geological and palaeoceanographic events. We present data on faunal (species and genera) richness, endemism patterns, diversity buildup (i.e. speciation processes), and evaluate the operation of the main biogeographical barriers and/or filters. Results Phylogenetic (proportion of sister species) and distributional (number of shared species) patterns are generally concordant with recognized biogeographical provinces in the Atlantic. The highly uneven distribution of species in certain genera appears to be related to their origin, with highest species richness in areas with the greatest phylogenetic depth. Diversity buildup in Atlantic reef fishes involved (1) diversification within each province, (2) isolation as a result of biogeographical barriers, and (3) stochastic accretion by means of dispersal between provinces. The timing of divergence events is not concordant among taxonomic groups. The three soft (non-terrestrial) inter-regional barriers (mid-Atlantic, Amazon, and Benguela) clearly act as ‘filters’ by restricting dispersal but at the same time allowing occasional crossings that apparently lead to the establishment of new populations and species. Fluctuations in the effectiveness of the filters, combined with ecological differences among provinces, apparently provide a mechanism for much of the recent diversification of reef fishes in the Atlantic. Main conclusions Our data set indicates that both historical events (e.g. Tethys closure) and relatively recent dispersal (with or without further speciation) have had a strong influence on Atlantic tropical marine biodiversity and have contributed to the biogeographical patterns we observe today; however, examples of the latter process outnumber those of the former. [ABSTRACT FROM AUTHOR]

Aims: To determine the suitability of eight different commercial broth media for Shiga toxin (Stx) production. Methods and Results: Shiga toxin-producing Escherichia coli (STEC) strains producing Stx1 or Stx2 were grown at 37°C (250 rev min−1) for 24 h in brain heart infusion broth, E. coli broth, Evans medium, Luria-Bertani broth, Penassay broth, buffered-peptone water, syncase broth and trypticase soy broth. Toxin production was measured by enzyme-linked immunosorbent assay (ELISA) in polymyxin-treated cell pellets and/or supernatants of cultures, ELISA optical densities reached 1 when isolates were grown for 2–4 h in E. coli broth in the presence of antibiotic. Besides, a collection of STEC-expressing Stx strains was evaluated and the Stx production was assayed in the supernatants and in polymyxin-treated pellets of bacterial growth after 4 h of cultivation in E. coli broth in the presence of antibiotic. Conclusions: The most suitable medium for Stx production was E. coli broth when the bacterial isolates were grown for 4 h in the presence of ciprofloxacin and the Stx production is detected in the supernatant. Significance and Impact of the Study: This study presents the first comprehensive comparison of different broth media with regard to Stx production to establish optimal culture conditions for STEC detection in routine diagnostic laboratories. [ABSTRACT FROM AUTHOR]

Objectives: To assess the frequency and variability of eleven non-metric dental crown traits (winging, shovel-shape, double shovel shape, Carabelli trait, deflecting wrinkle, protostylid, groove pattern, cusp number, sixth and seventh cusps) in permanent (UI1/UI2/UM1/LM1) teeth, in order to understanding the ethnic influence and the biological distance of the sample in study. Materials and methods: In this descriptive and quantitative study, frequency and variability of twelve non-metric dental crown traits were analyzed, through the ASUDAS System, in dental casts from 84 African-Colombian children of both sexes (42 females and 42 males), in mixed-dentition from Puerto Tejada, Cauca (Colombia) inhabitants. Results: High frequencies of Carabelli trait in grade 5; and +5 y +6 groove patterns, suggests Western dental complex influence. High frequencies of protostylid (P point or foramen secum) and deflecting wrinkle that suggest Mongoloid influence from the miscegenation with regional indigenous groups were observed. Winging, shovel-shape, double shovel, cusp number and cusp 6 showed low frequencies. Bilateral symmetry and absence of sexual dimorphism were demonstrated (except winging, shovel-shape and protostylid). [ABSTRACT FROM AUTHOR]

Complex networks have established themselves in recent years as being particularly suitable and flexible for representing and modelling several complex natural and artificial systems. In the same time in which the structural intricacies of such networks are being revealed and understood, efforts have also been directed at investigating how such connectivity properties define and constrain the dynamics of systems unfolding on such structures. However, less attention has been focused on hybrid systems, i.e. involving more than one type of network and/or dynamics. Several real systems present such an organization, e.g. the dynamics of a disease coexisting with the dynamics of the immune system. The current paper investigates a specific system involving diffusive (linear and nonlinear) dynamics taking place in a regular network while interacting with a complex network of defensive agents following Erdös-Rényi (ER) and Barabási-Albert (BA) graph models with moveable nodes. More specifically, the complex network is expected to control, and if possible, to extinguish the diffusion of some given unwanted process (e.g. fire, oil spilling, pest dissemination, and virus or bacteria reproduction during an infection). Two types of pattern evolution are considered: Fick and Gray-Scott. The nodes of the defensive network then interact with the diffusing patterns and communicate between themselves in order to control the diffusion. The main findings include the identification of higher efficiency for the BA control networks and the presence of relapses in the case of the ER model. [ABSTRACT FROM AUTHOR]

Autotaxin is a secreted cell motility-stimulating exo-phosphodiesterase with lysophospholipase D activity that generates bioactive lysophosphatidic acid. Lysophosphatidic acid has been implicated in various neural cell functions such as neurite remodeling, demyelination, survival and inhibition of axon growth. Here, we report on the in vivo expression of autotaxin in the brain during development and following neurotrauma. We found that autotaxin is expressed in the proliferating subventricular and choroid plexus epithelium during embryonic development. After birth, autotaxin is mainly found in white matter areas in the central nervous system. In the adult brain, autotaxin is solely expressed in leptomeningeal cells and oligodendrocyte precursor cells. Following neurotrauma, autotaxin is strongly up-regulated in reactive astrocytes adjacent to the lesion. The present study revealed the cellular distribution of autotaxin in the developing and lesioned brain and implies a function of autotaxin in oligodendrocyte precursor cells and brain injuries. [ABSTRACT FROM AUTHOR]

The article discusses the diagnostic relevance of pyuria in dialysis patients through a case study presentation involving of a 50-year-old white male on chronic maintenance hemodialysis evaluated for abdominal pain and urinary hesitancy. He acquired end-stage kidney disease as a complication of hypertension and renovascular disease and had been on peritoneal dialysis for 3.5 years. Clinical examinations conducted are discussed. Other information relative to the matter is presented.

Abstract: The weak absorption of the photoactive layer appears as a one of the main factors limiting organic photovoltaic solar cells performances. In order to increase the interaction of the incident light with the photoactive materials, we investigate the effect of a periodic patterning of the solar cells surface with microstructures in the optical wavelength scale. In this aim, we present an original all optical patterning technique of polymer films. The method is based on a laser controlled mass transport in azopolymer films leading to efficient deformation of the film surface in conjunction with the incoming light interference pattern. The technique is used to pattern one-dimensional gratings on the surface of solar cells. In the work presented here, the cell photoactive material is based on the interpenetrated network of a conjugated donor polymer and a fullerene derivative. The cells investigated are illuminated in a reverse configuration through a semi-transparent top cathode. The effect of the periodic structures onto the incident light propagation has been investigated through optical characterizations. We demonstrate that a part of the incident light can be trapped inside the solar cell layers due to diffraction onto the periodic structures. [Copyright &y& Elsevier]

This work describes how the formalization of complex network concepts in terms of discrete mathematics, especially mathematical morphology, allows a series of generalizations and important results ranging from new measurements of the network topology to new network growth models. First, the concepts of node degree and clustering coefficient are extended in order to characterize not only specific nodes, but any generic subnetwork. Second, the consideration of distance transform and rings are used to further extend those concepts in order to obtain a signature, instead of a single scalar measurement, ranging from the single node to whole graph scales. The enhanced discriminative potential of such extended measurements is illustrated with respect to the identification of correspondence between nodes in two complex networks, namely a protein-protein interaction network and a perturbed version of it. [ABSTRACT FROM AUTHOR]

The nonlinear dynamics of the parallel-plate electro- statically driven microstructure have been investigated with the objective of finding a dynamic voltage drive suitable for full-gap operation. Nonlinear dynamic modeling with phase-portrait presentation of both position and velocity of a realistic microstructure demonstrate that instability is avoided by a timely and sufficient reduction of the drive voltage. The simulation results are confirmed by experiments on devices fabricated in an epi-poly process. A 5.5-V peak harmonic drive voltage with frequency higher than 300 Hz allows repetitive microstructure motion up to 70% of gap without position feedback. The results of the analysis have been applied to the design of a new concept for positioning beyond the static pull-in limitation that does include position feedback. The measured instantaneous actuator displacement is compared with the desired displacement setting and, unlike traditional feedback, the voltage applied to the actuator is changed according to the comparison result between two values. The "low" level is below the static pull-in voltage and opposes the motion, thus bringing the structure back into a stable regime, while the "high" level is larger than the static pull-in voltage and will push the structure beyond the static pull-in displacement. Operation is limited only by the position jitter due to the time delay introduced by the readout circuits. Measurements confirm flexible operation up to a mechanical stopper positioned at 2 µm of the 2.25 µm wide gap with a 30 nm ripple. [ABSTRACT FROM AUTHOR]

Abstract: Pharmacological evidence indicates a specific role of 5-HT4 receptors on memory function. These receptors are members of G-protein-coupled 7-transmembrane domain receptor superfamily, are positively coupled to adenylyl cyclase, and are heterogeneously located in some structures important for memory, such as the hippocampus and cortical regions. To further clarify 5-HT4 receptors'' role in memory, the expression of these receptors in passive (P3) untrained and autoshaping (A3) trained (3 sessions) adult (3 months) and old (P9 or A9; 9 months) male rats was determined by autoradiography. Adult trained (A3) rats showed a better memory respect to old trained (A9). Using [3H] GR113808 as ligand (0.2 nM specific activity 81 Ci/mmol) for 5-HT4 receptor expression, 29 brain areas were analyzed, 16 areas of A3 and 17 of A9 animals displayed significant changes. The medial mammillary nucleus of A3 group showed diminished 5-HT4 receptor expression, and in other 15 brain areas of A3 or 10 of A9 animals, 5-HT4 receptors were increased. Thus, for A3 rats, 5-HT4 receptors were augmented in olfactory lobule, caudate putamen, fundus striatum, CA2, retrosplenial, frontal, temporal, occipital, and cingulate cortex. Also, 5-HT4 receptors were increased in olfactory tubercule, hippocampal CA1, parietal, piriform, and cingulate cortex of A9. However, hippocampal CA2 and CA3 areas, and frontal, parietal, and temporal cortex of A9 rats, expressed less 5-HT4 receptors. These findings suggest that serotonergic activity, via 5-HT4 receptors in hippocampal, striatum, and cortical areas, mediates memory function and provides further evidence for a complex and regionally specific regulation over 5-HT receptor expression during memory formation. [Copyright &y& Elsevier]

It has been suggested that kainic acid enhances opioid peptide release. However, no direct evidence exists to support this hypothesis. The main aim of the present study was to determine whether such release occurs in the hippocampus of the rat after status epilepticus induced by kainic acid. Microdialysis experiments revealed significant opioid peptide release in the hippocampus 90-150 min (100%) and 270-300 min (50%) after kainic acid-induced status epilepticus. The peptides released were identified by high-performance liquid chromatography linked to radioimmunoassay as Met-enkephalin, Leu-enkephalin, Dynorphin-A (1-6), and Dynorphin-A (1-8). Reduced extracellular opioid peptide immunoreactivity was detected 28 days after status epilepticus (38% compared with control situation). The present results indicate an important activation of opioid peptide systems by kainic acid-induced status epilepticus. In addition, the reduced hippocampal extracellular opioid peptide levels long-term after kainic acid administration could have important implications for the progressive nature of epileptogenesis. Hippocampus 2003;13:472-480. © 2003 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Submicrometric periodic patterning of an organic solar cell surface is investigated in order to optimize the photovoltaic conversion efficiency of the device. Patterning is achieved using a single-step all-optical technique based on photoinduced mass transport in azopolymer films. The polymer film with a structured surface is used as a substrate for an organic solar cell based on a copper phthalocyanine/C60 heterojunction. The effect of periodic patterning is investigated through the solar-cell optical-absorption properties and external quantum efficiency measurements. The possibility to increase the short circuit current density and the corresponding photovoltaic conversion efficiency is evidenced with one-dimensional periodic structures. [ABSTRACT FROM AUTHOR]

Introduction/Background Pain depends on the interaction of cognitive, and emotional factors. Individuals with negative coping strategies such as catastrophizing are prone to develop chronic pain syndromes, and poor functional outcomes. This maladapted behavior may be caused by abnormalities in attention systems and amplification of pain processing. Low back pain (LBP) is a disabling pain syndrome, but it is poorly known how catastrophizing affects brain activity. To explore catastrophizing neural correlates in LBP, we performed an fMRI study to verify the central pain system (pain matrix), and anticipation responses. Under unpredictable stimuli, we expected to see catastrophizing LBP showing lower ability to disengage attention to pain and lower pain threshold. Material and method We studied 43 LBP and 27 C subjects. LBP responded catastrophizing questionnaires (FABQ, CSQ). We used a pressure-pain device, to deliver stimuli in the thumbnail. Pain thresholds detected a priori, for moderate pain. Subjects performed 2 event-related fMRI experiments: 1 - Supraliminal Pain for the pain matrix study; 2 – Variable Pain for anticipation at unpredictable stimuli. T2* images acquired in a 3 T Siemens scanner. FMRI data was preprocessed and carried out using FSL tool. Corrected cluster significance threshold: P = 0.05. Results Both groups were similar for demographics. LBP had lower threshold for pressure stimulus. Both groups activated pain matrix areas, and had the same pattern during anticipation. When covarying with FABQ during experiment 2, LBP showed greater posterior cingulate cortex activation, indicating that in LBP, FABQ reduces brain activity. Conclusion LBP had lower pain threshold, suggesting central sensitization. Although both groups activated the pain matrix and had the same anticipation pattern, catastrophizing LBP had decreased activity in posterior cingulate cortex, suggesting negative coping skill influences pain appraisal in anticipation. The area belongs to the attention system and antinociception pathways in healthy subjects. Our results are in line with previous data showing greater posterior cingulate activity in low catastrophizers. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Avoiding (Re)extinction" by B. A. Minteer et al. from the April 18, 2014 issue regarding scientific specimen collection.