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Aging is associated a decrease in thirst sensation, which makes old people more susceptible to dehydration. Dehydration produces energy metabolism alterations. Our objective was to determinate the effect of water deprivation (WD) in the lipid metabolism of old male and female rats. Here we show that in the state of WD, aging and sex alters retroperitoneal white adipose tissue (R-WAT) weight of rats, WD old female rats had more lipolysis products than old male rats, a sexual dimorphism in the hormonal response related with metabolism of the adipose tissue of old rats during WD, the expression of P-para mRNA in R-WAT did not present any alteration in animals submitted to WD, the expression of Aqp7 mRNA in R-WAT is altered by WD, age, and sex. Also, WD stimulated an increase in the plasma concentration of oxytocin and the expression of mRNA of the oxytocin receptors in R-WAT.

Background and purpose: The analgesics, paracetamol and dipyrone are weak inhibitors of the cyclooxygenase isoforms 1 or 2 (COX‐1, COX‐2) but more potent on COX‐3. Both are also weak anti‐inflammatory agents, relative to their analgesic and antipyretic activities. In a model of inflammatory pain mediated by prostaglandins, both compounds were analgesic. We have analysed this shared effect further in order to elucidate the underlying mechanisms. Experimental approach: Inflammation was induced in one hind paw of rats by intraplantar injection of 250 μg λ‐carrageenan (CG) and the contralateral paw injected with saline. Nociceptive thresholds to mechanical stimulation were measured immediately before and for 6 h after, injection of CG. The analgesics were s.c. or locally (intraplantar) injected either 30 min before or 2 h after CG. In some groups, naltrexone was injected (s.c. or intraplantar), 1 h before CG. Key results: Pretreatment with paracetamol or dipyrone (60–360 mg kg−1) reversed hyperalgesia induced by CG and increased nociceptive threshold in the inflamed paw above the basal level (hypoalgesia). Paracetamol, but not dipyrone, also raised nociceptive thresholds in the non‐inflamed paw. Subcutaneous, but not local, administration of naltrexone, a specific opioid antagonist, reversed the hypoalgesia induced by paracetamol, but similar naltrexone treatment had no effect on dipyrone‐induced analgesia. Conclusions and implications: Although both paracetamol and dipyrone are inhibitors of COX isoforms and thus of prostaglandin biosynthesis and were analgesic in our model, their analgesic actions were functionally and mechanistically different. Satisfactory mechanisms of action for these analgesics still remain to be established. British Journal of Pharmacology (2008) 153, 760–768; doi:10.1038/sj.bjp.0707630; published online 24 December 2007

Pluto's twin is out in the cold Four trans-Neptunian objects are currently recognized as dwarf planets: Eris, Haumea, Makemake and Pluto. Of these, the 'demoted' planet Pluto has been studied for many years and has a detected atmosphere. The others are difficult to observe because of their extreme distance from the Sun, but a stellar occultation event on 6 November 2010 provided an opportunity for a closer look at Eris. The data obtained reveal Eris as a 'twin' for Pluto in terms of size, and previous work showed the two to have similar surface compositions. Eris, however, has no detectable atmosphere and its surface is bright, possibly a result of atmospheric collapse in an extremely cold environment. The dwarf planet Eris is a trans-Neptunian object with an orbital eccentricity of 0.44, an inclination of 44 degrees and a surface composition very similar to that of Pluto 1 . It resides at present at 95.7 astronomical units (1  au is the Earth-Sun distance) from Earth, near its aphelion and more than three times farther than Pluto. Owing to this great distance, measuring its size or detecting a putative atmosphere is difficult. Here we report the observation of a multi-chord stellar occultation by Eris on 6 November 2010 ut . The event is consistent with a spherical shape for Eris, with radius 1,163 ± 6 kilometres, density 2.52 ± 0.05 grams per cm 3 and a high visible geometric albedo, . No nitrogen, argon or methane atmospheres are detected with surface pressure larger than ∼1 nanobar, about 10,000 times more tenuous than Pluto's present atmosphere 2 , 3 , 4 , 5 . As Pluto's radius is estimated 3 , 4 , 5 , 6 , 7 , 8 to be between 1,150 and 1,200 kilometres, Eris appears as a Pluto twin, with a bright surface possibly caused by a collapsed atmosphere, owing to its cold environment. We anticipate that this atmosphere may periodically sublimate as Eris approaches its perihelion, at 37.8 astronomical units from the Sun.

A fundamental aspect in performance engineering of wireless sensor networks (WSN) is optimizing the set of links that can be concurrently activated to meet a given signal-to-interference-plus-noise ratio (SINR) threshold. The solution of this combinatorial problem is a key element in wireless link scheduling. Another key architectural goal in WSN is connectivity. The connectivity of sensor nodes is critical for WSN, as connected graphs can be used for both data collection and data dissemination. In this paper, we investigate the joint scheduling and connectivity problem in WSN assuming the SINR model. We propose algorithms to build connected communication graphs with power-efficient links to be scheduled simultaneously in one time slot. The algorithms aiming at minimizing the number of time slots needed to successfully schedule all the given links such that the nodes can communicate without interference in the SINR model. While power-efficient and interference-free schedules reduce energy consumption, minimization of the schedule length (shortest link scheduling) has the effect of maximizing network throughput. We propose one greedy randomized constructive heuristic, two local search procedures, and three greedy randomized adaptive search procedures metaheuristics. We report computational experiments comparing the effectiveness of the proposed algorithms. Our simulation also shows the trade-off between power consumption and schedule length and the results indicate that not only the overall performance of our algorithms, but also show that the total power and schedule length value of its solutions are better than the existing work.

Background/Aims: In this study we analyzed the mechanisms underlying celecoxib-induced analgesia in a model of inflammatory pain in rats, using the intracerebroventricular (i.c.v.) administration of selective opioid and cannabinoid antagonists. Methods and Results: Analgesic effects of celecoxib were prevented by selective µ-(β-funaltrexamine) and δ-(naltrindole), but not ĸ-(nor-binaltorphimine) opioid antagonists, given i.c.v. 30 min before celecoxib. Similar pretreatment with AM 251, but not SR 144528, cannabinoid CB 1 and CB 2 receptor antagonists, respectively, prevented celecoxib-induced analgesia. The fatty acid amide hydrolase inhibitor, URB 597, also prevented celecoxib-induced analgesia. Conclusions: Our data provided further evidence for the involvement of endogenous opioids and revealed a new cannabinoid component of the mechanism(s) underlying celecoxib-induced analgesia.

Failures in centrifugal pump shafts used in ore slurry applications can cause significant downtime in mining operations. However, limited studies focus on the comprehensive analysis of such failures, particularly in terms of fatigue behavior, microstructure, and stress distribution. This study investigates the fracture failure of an AISI 4140 steel shaft from a centrifugal ore slurry pump used by a large mining company in Brazil. The research includes chemical and microstructural analyses, as well as mechanical tests (tensile, hardness, impact, and fatigue), with numerical simulations conducted under defined boundary conditions: torque of 3885 Nm and shaft support through two rolling bearings. Results revealed that fatigue nucleation occurred at multiple stress concentration points in the threaded region, leading to final fracture. The maximum equivalent stress was quantified as 203.57 MPa, consistent with the simulation results. The shaft’s coarse bainitic microstructure reduced impact toughness, with a measured impact energy of 9 ± 2 J, while the fatigue limit was determined to be approximately 350 MPa.

To compare the production of hyperalgesic substances by cells from aged (A; 24-month) and juvenile (J; 2-month) rats. 4 x 10(5) purified mononuclear cells from J and A were 2 h-stimulated (test) or not (control) by 250 microg lambda-carrageenan/well. Supernatants (0.1 ml) were intraplantarly (ipl) injected in rat paws and development of mechanical hyperalgesia, in grams, evaluated. Rat interleukin 2 (IL 2) and prostaglandin E2 (PGE2) were also assessed for hyperalgesia development. Test supernatants from A compared with J induced significantly less hyperalgesia (-56 +/- 8.1 and -88.4 +/- 4.6 g, respectively, p < 0.05, ANOVA t test). Local injection of a specific, but not a control, antiserum against IL 2 significantly blocked both pure IL 2- and stimulated supernatants-derived hyperalgesia. In contrast to PGE-like materials, IL 2 content in supernatants was compatible with hyperalgesia development. Hyperalgesia induced by test supernatants was significantly less intense when derived from aged animals. IL 2 may have accounted for such hyperalgesia.

ABSTRACT Closure of the rotator cuff interval is an important component of open stabilization techniques in shoulder surgery. This study describes a technique in which the deep layer of the capsule within the rotator cuff interval is closed arthroscopically. The effect of closure of this capsule within the rotator cuff interval on glenohumeral motion also is quantified. Sutures were placed from the superior glenohumeral ligament to the middle glenohumeral ligament and tied intra-articularly in fresh-frozen cadaveric shoulders. Closure of the interval capsule resulted in statistically significant limitation of humeral elevation, external rotation, and extension. Arthroscopic closure of the deep layer of the rotator cuff interval capsule produced a visible superior shifting of the middle and inferior glenohumeral ligaments and imbricated the anterosuperior capsule of the shoulder. In addition, this procedure can be performed in conjunction with arthroscopic capsulolabral reconstruction.

Este artigo parte da constatação de um deslocamento do lugar ocupado pela ideia da representação na esquerda contemporânea para embasar um diagnóstico da experiência do PT na história política recente no Brasil. Embora tivesse partido de uma contestação da \"democracia representativa\", o PT terminou por patrocinar o mais vasto experimento de multiplicação de formas e instâncias de representação em curso no Brasil contemporâneo, frequentemente sob a rubrica de um ideal \"participativo\". O artigo tende a sublinhar o caráter inapelável dessa \"deriva\" rumo à representação, bem como identificar a raiz desses experimentos num compromisso político do partido com certos setores até então periféricos da população, bem mais que numa presumível clareza ideológica quanto a diagnósticos teoricamente orientados sobre o Brasil.