55 resultados para Traffic volume.


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BACKGROUND AND PURPOSE: Functional brain variability has been scarcely investigated in cognitively healthy elderly subjects, and it is currently debated whether previous findings of regional metabolic variability are artifacts associated with brain atrophy. The primary purpose of this study was to test whether there is regional cerebral age-related hypometabolism specifically in later stages of life. MATERIALS AND METHODS: MR imaging and FDG-PET data were acquired from 55 cognitively healthy elderly subjects, and voxel-based linear correlations between age and GM volume or regional cerebral metabolism were conducted by using SPM5 in images with and without correction for PVE. To investigate sex-specific differences in the pattern of brain aging, we repeated the above voxelwise calculations after dividing our sample by sex. RESULTS: Our analysis revealed 2 large clusters of age-related metabolic decrease in the overall sample, 1 in the left orbitofrontal cortex and the other in the right temporolimbic region, encompassing the hippocampus, the parahippocampal gyrus, and the amygdala. The division of our sample by sex revealed significant sex-specific age-related metabolic decrease in the left temporolimbic region of men and in the left dorsolateral frontal cortex of women. When we applied atrophy correction to our PET data, none of the above-mentioned correlations remained significant. CONCLUSIONS: Our findings suggest that age-related functional brain variability in cognitively healthy elderly individuals is largely secondary to the degree of regional brain atrophy, and the findings provide support to the notion that appropriate PVE correction is a key tool in neuroimaging investigations.

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OBJECTIVE center dot To evaluate early trifecta outcomes after robotic-assisted radical prostatectomy (RARP) performed by a high-volume surgeon. PATIENTS AND METHODS center dot We evaluated prospectively 1100 consecutive patients who underwent RARP performed by one surgeon. In all, 541 men were considered potent before RARP; of these 404 underwent bilateral full nerve sparing and were included in this analysis. center dot Baseline and postoperative urinary and sexual functions were assessed using self-administered validated questionnaires. center dot Postoperative continence was defined as the use of no pads; potency was defined as the ability to achieve and maintain satisfactory erections for sexual intercourse > 50% of times, with or without the use of oral phosphodiesterase type 5 inhibitors; Biochemical recurrence (BCR) was defined as two consecutive PSA levels of > 0.2 ng/mL after RARP. center dot Results were compared between three age groups: Group 1, < 55 years, Group 2, 56-65 years and Group 3, > 65 years. RESULTS center dot The trifecta rates at 6 weeks, 3, 6, 12, and 18 months after RARP were 42.8%, 65.3%, 80.3%, 86% and 91%, respectively. center dot There were no statistically significant differences in the continence and BCR-free rates between the three age groups at all postoperative intervals analysed. center dot Nevertheless, younger men had higher potency rates and shorter time to recovery of sexual function when compared with older men at 6 weeks, 3, 6 and 12 months after RARP (P < 0.01 at all time points). center dot Similarly, younger men also had a shorter time to achieving the trifecta and had higher trifecta rates at 6 weeks, 3 and 6 months after RARP compared with older men (P < 0.01 at all time points). CONCLUSION center dot RARP offers excellent short-term trifecta outcomes when performed by an experienced surgeon. center dot Younger men had a shorter time to achieving the trifecta and higher overall trifecta rates when compared with older men at 6 weeks, 3 and 6 months after RARP.

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Background and objective: Vascular endothelial growth factor (VEGF) is known to increase vascular permeability and promote angiogenesis. It is expressed in most types of pleural effusions. However, the exact role of VEGF in the development of pleural effusions has yet to be determined. The anti-VEGF mAb, bevacizumab, has been used in the treatment of cancer to reduce local angiogenesis and tumour progression. This study describes the acute effects of VEGF blockade on the expression of inflammatory cytokines and pleural fluid accumulation. Methods: One hundred and twelve New Zealand rabbits received intrapleural injections of either talc or silver nitrate. In each group, half the animals received an intravenous injection of bevacizumab, 30 min before the intrapleural agent was administered. Five animals from each subgroup were sacrificed 1, 2, 3, 4 or 7 days after the procedure. Twelve rabbits were used to evaluate vascular permeability using Evans`s blue dye. Pleural fluid volume and cytokines were quantified. Results: Animals pretreated with anti-VEGF antibody showed significant reductions in pleural fluid volumes after talc or silver nitrate injection. IL-8 levels, vascular permeability and macroscopic pleural adhesion scores were also reduced in the groups that received bevacizumab. Conclusions: This study showed that bevacizumab interferes in the acute phase of pleural inflammation induced by silver nitrate or talc, reinforcing the role of VEGF as a key mediator in the production of pleural effusions. The results also suggest that bevacizumab should probably be avoided in patients requiring pleurodesis.

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Neuroimaging studies in bipolar disorder report gray matter volume (GMV) abnormalities in neural regions implicated in emotion regulation. This includes a reduction in ventral/orbital medial prefrontal cortex (OMPFC) GMV and, inconsistently, increases in amygdala GMV. We aimed to examine OMPFC and amygdala GMV in bipolar disorder type 1 patients (BPI) versus healthy control participants (HC), and the potential confounding effects of gender, clinical and illness history variables and psychotropic medication upon any group differences that were demonstrated in OMPFC and amygdala GMV Images were acquired from 27 BPI (17 euthymic, 10 depressed) and 28 age- and gender-matched HC in a 3T Siemens scanner. Data were analyzed with SPM5 using voxel-based morphometry (VBM) to assess main effects of diagnostic group and gender upon whole brain (WB) GMV. Post-hoc analyses were subsequently performed using SPSS to examine the extent to which clinical and illness history variables and psychotropic medication contributed to GMV abnormalities in BPI in a priori and non-a priori regions has demonstrated by the above VBM analyses. BPI showed reduced GMV in bilateral posteromedial rectal gyrus (PMRG), but no abnormalities in amygdala GMV. BPI also showed reduced GMV in two non-a priori regions: left parahippocampal gyrus and left putamen. For left PMRG GMV, there was a significant group by gender by trait anxiety interaction. GMV was significantly reduced in male low-trait anxiety BPI versus male low-trait anxiety HC, and in high-versus low-trait anxiety male BPI. Our results show that in BPI there were significant effects of gender and trait-anxiety, with male BPI and those high in trait-anxiety showing reduced left PMRG GMV. PMRG is part of medial prefrontal network implicated in visceromotor and emotion regulation. (C) 2008 Elsevier Ireland Ltd. All rights reserved.

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Objective: To examine whether there is an association between fetal and/or placental weight and exposure to ambient levels of air pollution in mice. Design: Chronic experiments on mice that were exposed to polluted vs. clean air. Setting: Environmental exposure to atmospheric pollution. Animal(S): Female Swiss mice (n = 70) were maintained at different stages of gestation in an exposure chamber located at an intersection with heavy traffic in a major city in Brazil. Control mice were maintained in a similar chamber, located adjacent to the exposure chamber but equipped with filters for particles and reactive gases. Intervention(s): Animals were divided into six groups as follows: no exposure, exposure to a polluted chamber throughout gestation, exposure to a polluted chamber during the 1st week of pregnancy, exposure to a polluted chamber during the 2nd and 3rd weeks, exposure to a polluted chamber during the 1st and 2nd week, and exposure to a polluted chamber during the 3rd week. Main Outcome Measure(S): At the end of the gestational period, the determination of fetal and placental weight was performed after cesarean section. Result(s): Exposure to air pollution during the 1st week of pregnancy promoted a significant reduction in fetal weight. Mice exposed to polluted air, in any phase of gestation, presented with lower placental weight in comparison to mice maintained in clean chambers. Conclusion(s): Exposure to ambient levels of traffic pollution at early phases of gestation is a determinant for decreased final fetal weight. Placental weight is reduced with exposure to air pollution at any phase of gestation. (Fertil Steril (R) 2008;90:1921-4. (C)2008 by American Society for Reproductive Medicine.)

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Rationale- Chronic exposure to air pollution has been associated with adverse effects on children`s lung growth. Objectives: We analyzed the effects of chronic exposure to urban levels of particulate matter (PM) on selected phases of mouse lung development. Methods: The exposure occurred in two open-top chambers (filtered and nonfiltered) placed 20 m from a street with heavy traffic in Sao Paulo, 24 hours/day for 8 months. There was a significant reduction of the levels of PM(2.5) inside the filtered chamber (filtered = 2.9 +/- 3.0 mu g/m(3), nonfiltered = 16.8 +/- 8.3 mu g/m(3); P = 0.001). At this exposure site, vehicular sources are the major components of PM(2.5) (PM <= 2.5 mu m). Exposure of the parental generation in the two chambers occurred from the 10th to the 120th days of life. After mating and birth of offspring, a crossover of mothers and pups occurred within the chambers, resulting in four groups of pups: nonexposed, prenatal, postnatal, and pre+postnatal. Offspring were killed at the age of 15 (n = 42) and 90 (n = 35) days; lungs were analyzed by morphometry for surface to volume ratio (as an estimator of alveolization). Pressure-volume curves were performed in the older groups, using a 20-ml plethysmograph. Measurements and Main Results: Mice exposed to PM(2.5) pre+postnatally presented a smaller surface to volume ratio when compared with nonexposed animals (P = 0.036). The pre+postnatal group presented reduced inspiratory and expiratory volumes at higher levels of transpulmonary pressure (P = 0.001). There were no differences among prenatal and postnatal exposure and nonexposed animals. Conclusions: Our data provide anatomical and functional support to the concept that chronic exposure to urban PM affects lung growth.

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Context.-Studies analyzing the concordance of biopsy and radical prostatectomy (RP) Gleason scores have limitations. Some included 2 or more centers, used historical controls from the early prostate specific antigen era or lacked a clear definition of the biopsy schemes. Furthermore, most did not control the results for prostate volume. Objective.-To confirm whether prediction of RP Gleason score can be optimized by taking more biopsy cores in a contemporary series of patients, with pathologic samples analyzed by the same pathologist, and controlling these results for prostate volume. Design.-The study comprised a retrospective case-control analysis of 393 patients with prostate cancer treated with RP. Patients were divided into 3 groups: those in group 1 underwent a 6-core biopsy; group 2, an 8-core biopsy; and group 3, a 10 or more-core biopsy. Concordance rates between biopsy and RP Gleason scores, as well as the rates of undergrading and overgrading, were determined for each biopsy scheme. Results.-Concordance rates were 60.9%, 58.3%, and 64.6% for patients from groups 1, 2, and 3, respectively (P = .18). When we analyzed patients with prostate volumes of less than 50 cm(3), concordance rates were 58.3%, 58.3%, and 65.1% for each group, respectively (P = .03). Among patients with prostate volumes of 50 cm3 or more, concordance rates were 70%, 58.1%, and 63.6%, respectively (P = .66). Conclusions.-Taking 10 or more cores can improve the prediction of RP Gleason score in patients with prostate volumes of less than 50 cm3. For patients with prostate volumes of 50 cm3 or more, increasing the biopsy cores to 10 or more did not improve prediction of RP Gleason score.

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Background and objective: Dynamic indices represented by systolic pressure variation and pulse pressure variation have been demonstrated to be more accurate than filling pressures in predicting fluid responsiveness. However, the literature is scarce concerning the impact of different ventilatory modes on these indices. We hypothesized that systolic pressure variation or pulse pressure variation could be affected differently by volume-controlled ventilation and pressure-controlled ventilation in an experimental model, during normovolaemia and hypovolaemia. Method: Thirty-two anaesthetized rabbits were randomly allocated into four groups according to ventilatory modality and volaemic status where G1-ConPCV was the pressure-controlled ventilation control group, G2-HemPCV was associated with haemorrhage, G3-ConVCV was the volume-controlled ventilation control group and G4-HemVCV was associated with haemorrhage. In the haemorrhage groups, blood was removed in two stages: 15% of the estimated blood volume withdrawal at M1, and, 30 min later, an additional 15% at M2. Data were submitted to analysis of variance for repeated measures; a value of P < 0.05 was considered to be statistically significant. Results: At MO (baseline), no significant differences were observed among groups. At M1, dynamic parameters differed significantly among the control and hypovolaemic groups (P < 0.05) but not between ventilation modes. However, when 30% of the estimated blood volume was removed (M2), dynamic parameters became significantly higher in animals under volume-controlled ventilation when compared with those under pressure-controlled ventilation. Conclusions: Under normovolaemia and moderate haemorrhage, dynamic parameters were not influenced by either ventilatory modalities. However, in the second stage of haemorrhage (30%), animals in volume-controlled ventilation presented higher values of systolic pressure variation and pulse pressure variation when compared with those submitted to pressure-controlled ventilation.

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Background: Traffic accidents constitute the main cause of death in the first decades of life. Traumatic brain injury is the event most responsible for the severity of these accidents. The SBN started an educational program for the prevention of traffic accidents, adapted from the American model ""Think First"" to the Brazilian environment, since 1995, with special effort devoted to the prevention of TBI by using seat belts and motorcycle helmets. The objective of the present study was to set up a traffic accident prevention program based on the adapted Think First and to evaluate its impact by comparing epidemiological variables before and after the beginning of the program. Methods: The program was executed in Maringa city, from September 2004 to August 2005, with educational actions targeting the entire population, especially teenagers and young adults. The program was implemented by building a network of information facilitators and multipliers inside the organized civil society, with widespread population dissemination. To measure the impact of the program, a specific software was developed for the storage and processing of the epidemiological variables. Results: The results showed a reduction of trauma severity due to traffic accidents after the execution of the program, mainly TBI. Conclusions: The adapted Think First was systematically implemented and its impact measured for the first time in Brazil, revealing the usefulness of the program for reducing trauma and TBI severity in traffic accidents through public education and representing a standardized model of implementation in a developing country. (C) 2009 Elsevier Inc. All rights reserved.

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Secretion of vasopressin (VP), oxytocin (OT) and atrial natriuretic peptide (ANP) is an essential mechanism for the maintenance of hydromineral homeostasis. Secretion of these hormones is modulated by several circulating factors, including oestradiol. However, it remains unclear how oestradiol exerts this modulation. In the present study we investigated the participation of oestradiol in the secretion of VP, OT and ANP and in activation of vasopressinergic and oxytocinergic neurones of the supraoptic (SON) and paraventricular (PVN) nuclei of the hypothalamus in response to extracellular volume expansion (EVE). For this purpose, ovariectomised (OVX) rats treated for 7 days with vehicle (corn oil, 0.1 ml/rat, OVX+O group) or oestradiol (oestradiol cypionate, 10 mu g/kg, OVX+E group) were subjected to either isotonic (0.15 m NaCl, 2 ml/100 g b.w., i.v.) or hypertonic (0.30 m NaCl, 2 ml/100 g b.w., i.v.) EVE. Blood samples were collected for plasma VP, OT and ANP determination. Another group of rats was subjected to cerebral perfusion, and brain sections were processed for c-Fos-VP and c-Fos-OT double-labelling immunohistochemistry. In OVX+O rats, we observed that both isotonic and hypertonic EVE increased plasma OT and ANP concentrations, although no changes were observed in VP secretion. Oestradiol replacement did not alter hormonal secretion in response to isotonic EVE, but it increased VP secretion and potentiated plasma OT and ANP concentrations in response to hypertonic EVE. Immunohistochemical data showed that, in the OVX+O group, hypertonic EVE increased the number of c-Fos-OT and c-Fos-VP double-labelled neurones in the PVN and SON. Oestradiol replacement did not alter neuronal activation in response to isotonic EVE, but it potentiated vasopressinergic and oxytocinergic neuronal activation in the medial magnocellular PVN (PaMM) and SON. Taken together, these results suggest that oestradiol increases the responsiveness of vasopressinergic and oxytocinergic magnocellular neurones in the PVN and SON in response to osmotic stimulation.

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The endocannabinoid system includes important signaling molecules that are involved in several homeostatic and neuroendocrine functions. In the present study, we evaluated the effects of the type 1 cannabinoid (CB(1)) receptor antagonist, rimonabant (10 mg/kg, p.o.), on hormone secretion, neuronal activation and mRNA expression in the hypothalamus following isotonic (I-) or hypertonic (H-) extracellular volume expansion (EVE). The total nitrate content in the PVN and SON was also assessed under the same experimental conditions. Our results showed that OT and AVP plasma concentrations were increased in response to H-EVE, while decreased AVP levels were found following I-EVE. Accordingly, both I- and H-EVE stimulated oxytocinergic neuronal activation, as evidenced by the increased number of c-Fos/OT double labeled neurons in the hypothalamus. The vasopressinergic cells of the PVN and SON, however, were only activated in response to H-EVE. Furthermore, increased amounts of both AVP and OT mRNAs were found in the hypothalamus following EVE. Pretreatment with rimonabant significantly potentiated hormone secretion and also vasopressinergic and oxytocinergic neuronal activation induced by EVE, although decreased AVP and OT mRNA expression was found in the hypothalami of rimonabant pretreated groups. In addition, the nitrate content in the PVN and SON was not altered in response to EVE or rimonabant pretreatment. Taken together, these results suggest that the CB(1) receptor may modulate several events that contribute to the development of appropriate responses to increased fluid volume and osmolality. (C) 2010 Elsevier Inc. All rights reserved.

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Several studies suggest that hypothalamic cocaine- and amphetamine-regulated transcript (CART) may interact with the hypothalamic-pituitary-adrenal (HPA) axis in the control of neuroendocrine function and may also participate in cardiovascular regulation. Therefore, this study aimed to evaluate, in experimental models of isotonic (I-EVE) and hypertonic (H-EVE) extracellular volume expansion and water deprivation (WD), the activation of CART- and corticotrophin releasing factor (CRF)-immunoreactive neurons, as well as the relative expression of CART and CRF mRNAs in the paraventricular (PVN) and supraoptic (SON) nuclei of the hypothalamus. Both H-EVE (0.30M NaCl, 2mL/100g of body weight, in 1 minute) and 24 hours of WD significantly increased plasma sodium concentrations, producing, respectively, either an increase or a decrease in extracellular volume. I-EVE (0.15M NaCl, 2mL/100g of body weight, in 1 minute) evoked a significant increase in the circulating volume accompanied by unaltered plasma concentrations of sodium. CART-expressing neurons of both magnocellular and parvocellular hypothalamic divisions were activated to produce Fos in response to H-EVE but not in response to I-EVE. Furthermore, increased expression of CART mRNA was found in the PVN of H-EVE but not I-EVE rats. These data show for the first time that EVE not only activates hypothalamic CRF neurons but also increases CRF mRNA expression in the PVN. In contrast, WD increases the number of CART-immunoreactive neurons activated to produce Fos in the PVN and SON but does not change the number of neurons double labeled for Fos and CRF or expression of CRF mRNA in the PVN. These findings provided new insights into the participation of CART in diverse processes within the PVN and SON, including its possible involvement in activation of the HPA axis and cardiovascular regulation in response to changes in extracellular volume and osmolality. (C) 2011 IBRO. Published by Elsevier Ltd. All rights reserved.

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Recent evidence has shown that the serotonergic mechanism of the lateral parabrachial nucleus (LPBN) participates in the regulation of renal and hormonal responses to isotonic blood volume expansion (BVE). We investigated the BVE-induced Fos activation along forebrain and hindbrain nuclei and particularly within the serotonergic clusters of the raphe system that directly project to the LPBN. We also examined whether there are changes in the concentration of serotonin (5HT) within the raphe nucleus in response to the same stimulus. With this purpose, we analyzed the cells doubly labeled for Fos and Fluorogold (FG) following BVE (NaCl 0.15 M, 2 ml/100 g b.w., 1 min) 7 days after FG injection into the LPBN. Compared with the control group, blood volume-expanded rats showed a significant greater number of Fos-FG double-labeled cells along the nucleus of the solitary tract, locus coeruleus, hypothalamic paraventricular nucleus, central extended amygdala complex, and dorsal raphe nucleus (DRN) cells. Our study also showed an increase in the number of serotonergic DRN neurons activated in response to isotonic BVE. We also observed decreased levels of 5HT and its metabolite 5-hydroxyindoleacetic acid (measured by high-pressure liquid chromatography) within the raphe nucleus 15 min after BVE. Given our previous evidence on the role of the serotonergic system in the LPBN after BVE, the present morphofunctional findings suggest the existence of a key pathway (DRN-LPBN) that may control BVE response through the modulation of 5HT release. (c) 2008 Wiley-Liss, Inc.

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Production and secretion of testosterone in Leydig cells are mainly controlled by the luteinizing hormone (LH). Biochemical evidences suggest that the activity of Cl(-) ions can modulate the steroidogenic process, but the specific ion channels involved are not known. Here, we extend the characterization of Cl(-) channels in mice Leydig cells (50-60 days old) by describing volume- activated Cl(-) currents (I(Cl,swell)). The amplitude of I(Cl,swell) is dependent on the osmotic gradient across the cell membrane, with an apparent EC(50) of similar to 75 mOsm. These currents display the typical biophysical signature of volume- activated anion channels (VRAC): dependence on intracellular ATP, outward rectification, inactivation at positive potentials, and selectivity sequence (I(-)>Cl(-)>F(-)). Staurosporine (200 nM) did not block the activation of I(Cl), swell. The block induced by 5-nitro-2-(3-phenylpropylamino) benzoic acid (NPPB; 128 mu M), SITS (200 mu M), ATP (500 mu M), pyridoxalphosphate-6- azophenyl-2`,4`-disulfonate (PPADS; 100 mu M), and Suramin (10 mu M) were described by the permeant blocker model with apparent dissociation constant at 0 mV K(d)(0) and fractional distance of the binding site (delta) of 334 mu M and 47%, 880 mu M and 35%, 2,100 mu M and 49%, 188 mu M and 27%, and 66.5 mu M and 49%, respectively. These numbers were derived from the peak value of the currents. We conclude that ICl, swell in Leydig cells are activated independently of purinergic stimulation, that Suramin and PPADS block these currents by a direct interaction with VRAC and that ATP is able to permeate this channel.

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Objective To investigate whether standardization of the multiplanar view (SMV) when evaluating the uterus using three-dimensional ultrasonography (3D-US) improves intra-and interobserver reliability and agreement with regard to endometrial measurement. Methods Two-dimensional (2D) and 3D-US was used to measure endometrial thickness by two observers in 30 women undergoing assisted reproduction treatment. Endometrial volume was measured with Virtual Organ Computer-aided AnaLysis (VOCAL (TM)) in the longitudinal (A) and coronal (C) planes using an unmodified multiplanar view (UMV) and a standardized multiplanar view (SMV). Measurement reliability was evaluated by intraclass correlation coefficient (ICC) and agreement was examined using Bland-Altman plots with limits of agreement (LoA). The ease of outlining the endometrial-myometrial interface was compared between the A-and C-planes using subjective assessment. Results Endometrial volume measurements using the SMV and A-plane were more reliable (intra-and interobserver ICCs, 0.979 and 0.975, respectively) than were measurements of endometrial thickness using 2D-US (intra-and interobserver ICCs, 0.742 and 0.702, respectively) or 3D-US (intra-and interobserver ICCs, 0.890 and 0.784, respectively). The LoAs were narrower for SMV than for UMV. Reliability and agreement were not much different between the A- and C-planes. However the observers agreed that delineating the endometrial-myometrial interface using the A-plane was easier (first and second observer, 50.0 and 46.7%, respectively) or `comparable` (50 and 53.3%, respectively), but never more difficult than using the C-plane. Conclusions Endometrial volume measurements are more reliable than endometrial thickness measurements and are best performed using SMV and the A-plane. Copyright (C) 2011 ISUOG. Published by John Wiley & Sons, Ltd.