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Adhesives can be made by patterning surfaces with discrete adhesive elements. Nature uses this approach to provide animals with highly adaptive and robust approaches towards gaining an effective grip on surfaces. The mechanism of patterned surface adhesion involve many different attachment principles, adhesive site interactions, and probabilistic effects, the interplay of which is not understood. This limits our ability to design patterned surface adhesives for engineering applications. In this work, we quantify how a mechanically patterned adhesive based on passive mushroom-shaped elements performs. We explore a range of surface design features and model the mechanical adhesion dynamics with an approach based on the fiber bundle model (FBM). We find that the fiber bundle model can be used to rationalize the observations after modifying it to capture the initial non-linear force response of the adhesives. Additionally, we investigate the behavior of the system's elastic energy and damage energy, as it is stretched under strain-controlled conditions. Our experimental data indicates that the elastic energy has a maximum that appears after the macroscopic strength (σc), corresponding to strains where a full rupture of the system can no longer be prevented. Moreover, we observed that below the maximum of the constitutive curve σc, the elastic energy consistently exceeds the damage energy. Finally, we found that the derivative of the elastic energy has a maximum, which always appears before σc. Therefore, the derivative of the elastic energy would serve as a reliable signal of upcoming catastrophic failure in experiments under stress-controlled conditions. [ABSTRACT FROM AUTHOR]

Trypanosomosis is a tropical disease caused by various protozoan haemoparasites, which affects wild and domestic animals, the latter ones related to worldwide livestock production systems. Species such as Trypanosoma vivax and Trypanosoma evansi have been described using serological and molecular tools in several countries from South and Central America. However, Ecuador presents a relevant knowledge gap in the associated general epidemiology and risk factors of the disease. Therefore, the objective of this study was to determine the seroprevalence of trypanosomosis in cattle from different regions of Ecuador. 745 serum samples from 7 Coastal and 3 Amazon provinces were screened for IgG anti-Trypanosoma spp. antibodies, using an in-house indirect ELISA. The seropositivity was explored and associated with several variables such as sex, age, breed, region, management, and province, using statistical tools. The general seroprevalence of trypanosomosis was 19.1% (95% CI: 16.30–22.1%). The Amazonian provinces of Sucumbíos and Napo and the Coastal province of Esmeraldas presented the highest seroprevalence values of 36.7% (95% CI: 27.67–46.47%), 23.64% (95% CI: 16.06–32.68%) and 25% (95% CI: 15.99–35.94%), respectively. Statistical significance was found for the region, province, and management variables, indicating as relevant risk factors the extensive management and Amazon location of the cattle analyzed. Specific actions should be taken to identify the exact species on reservoirs and susceptible hosts, evaluate the implication of farm management and cattle movement as risk factors, and implement surveillance and treatment plans for affected herds. [ABSTRACT FROM AUTHOR]

Copyright of Agriscientia is the property of Revista AgriScientia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the present work, we investigate experimentally and numerically the motion of solid macroscopic spheres (Brownian and colloidal effects are negligible) when settling from rest in a quiescent fluid toward a solid wall under confined and unconfined configurations. Particle trajectories for spheres of two types of materials are measured using a high-speed digital camera. For unconfined configurations, our experimental findings are in excellent agreement with well-established analytical frameworks, used to describe the forces acting on the sphere. Besides, the experimental values of the terminal velocity obtained for different confinements are also in very good agreement with previous theoretical formulations. Similar conditions are simulated using a resolved CFD-DEM approach. After adjusting the parameters of the numerical model, we analyze the particle dynamic under several confinement conditions. The simulations results are contrasted with the experimental findings, obtaining a good agreement. We analyze several systems varying the radius of the bead and show the excellent agreement of our results with previous analytical approaches. However, the results indicate that confined particles have a distinct dynamics response when approaching the wall. Consequently, their motion cannot be described by the analytical framework introduced for the infinite system. Indeed, the confinement strongly affects the spatial scale where the particle is affected by the bottom wall and, accordingly, the dimensionless results can not be collapsed in a single master curve, using the particle size as a characteristic length. Alternatively, we rationalize our findings using a kinematic approximation to highlight the relevant scale of the problem. Our outcomes suggest it is possible to determine a new spatial scale to describe the collisional process, depending on the specific confining conditions. [ABSTRACT FROM AUTHOR]

With people trying to keep a safe distance from others due to the COVID-19 outbreak, the way in which pedestrians walk has completely changed since the pandemic broke out1,2. In this work, laboratory experiments demonstrate the effect of several variables—such as the pedestrian density, the walking speed and the prescribed safety distance—on the interpersonal distance established when people move within relatively dense crowds. Notably, we observe that the density should not be higher than 0.16 pedestrians per square meter (around 6 m2 per pedestrian) in order to guarantee an interpersonal distance of 1 m. Although the extrapolation of our findings to other more realistic scenarios is not straightforward, they can be used as a first approach to establish density restrictions in urban and architectonic spaces based on scientific evidence. [ABSTRACT FROM AUTHOR]

Background: To investigate the incidence of non-cancer mortalities and prognostic factors associated with competitive causes of death in a homogeneous cohort of patients with locally advanced head and neck cancer treated with radiotherapy and systemic treatment.Methods: This study included 284 patients with locally advanced head and neck cancer treated with radiotherapy and systemic treatment between 2005 and 2017. The cumulative incidence of death associated with tumour, second tumours, treatment, side effects and comorbidity was calculated. A Fine and Gray regression model was used to investigate factors associated with cancer and competitive mortality.Results: The cumulative incidence of tumoral death at 5 and 10 years were 35 and 47% respectively, whereas the cumulative incidence of competitive mortality were 10 and 12% respectively. In the multivariate analysis, age and comorbidity were independent factors for non-cancer mortality. Patients with a high risk of non-cancer mortality presented a cumulative incidence of 17.3% at 5 years and 18.4% at 10 years.Conclusions: This study demonstrated a high incidence of competing mortality in older patients with comorbidities. Non-cancer deaths should be considered when selecting patients for combination therapies and in the study design ofclinical trials. [ABSTRACT FROM AUTHOR]

Background and purpose: Alcohol overuse (AOu) is considered an important risk factor for spontaneous intracerebral hemorrhage (ICH). The clinical and outcome characteristics of these patients (AOu‐ICH) are not well known. Methods: All patients with ICH admitted to a single university tertiary stroke center were prospectively studied from May 2005 to May 2015. Demographic profiles, radiologic characteristics and clinical outcomes of patients with acute ICH and previous AOu (>40 g/day or >300 g/week) were analyzed. Results: During the study period, 555 patients with spontaneous primary ICH met the inclusion criteria. A total of 81 patients (14.6%) reported AOu (24.3% of men vs. 3.1% of women; P < 0.0001; mean age, 63 years old for AOu vs. 74 years old for non‐AOu; P < 0.0001). Of the classic cardiovascular risk factors, only smoking was associated with AOu (63% vs. 12.2% of non‐AOu; P < 0.0001). Initial severity and hematoma volume were similar in both groups, with no observed differences in stroke care or in‐hospital medical complications. Patients with AOu had worse outcome (modified Rankin Scale score, 3–6 points) than patients without AOu at 3 months [odds ratio (OR), 2.50; 95% confidence interval (CI), 1.32–4.75; P = 0.005] and 12 months (OR, 2.47; 95% CI, 1.23–5.00; P = 0.011). A similar trend was observed at 5 years (OR, 2.48; 95% CI, 0.96–6.39; P = 0.059). Conclusions: Alcohol overuse was present in 14.6% of patients with ICH, who were predominantly male, smokers and a mean of 11 years younger than the non‐AOu group. Despite a lack of differences in initial clinical severity, stroke care and early medical complications, patients with AOu had worse short‐ and long‐term outcomes. [ABSTRACT FROM AUTHOR]

Abstract: Over the past decades, the development of high performance lightweight polymer nanocomposites and, in particular, of epoxy nanocomposites has become one the greatest challenges in material science. The ultimate goal of epoxy nanocomposites is to extrapolate the exceptional intrinsic properties of the nanoparticles to the bulk matrix. However, in spite of the efforts, this objective is still to be attained at commercially attractive scales. Key aspects to achieve this are ultimately the full understanding of network structure, the dispersion degree of the nanoparticles, the interfacial adhesion at the phase boundaries and the control of the localization and orientation of the nanoparticles in the epoxy system. In this Personal Account, we critically discuss the state of the art and evaluate the strategies to overcome these barriers. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Zoology is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background and purpose: Patients with acute intracerebral hemorrhage (ICH) pretreated with antithrombotic drugs may have increased early hematoma growth, which would increase mortality risk. The effect of antiplatelet (AP) and vitamin K antagonist (VKA) pretreatment on ultra-early hematoma growth (uHG) and its relationship with mortality in patients with acute supratentorial ICH was analyzed. Methods: This is an observational retrospective study of a prospective register of 197 ICH patients with first computed tomography (CT) scan taken <6 h from ICH symptom onset. ICH volume was calculated by the ABC/2 formula and uHG by the baseline ICH volume/onset-to-CT time (ml/h) formula. The uHG analysis took into account the patient's pretreatment (none, AP or VKA) and the relationship between uHG and very-early (first 24 h) and 3-month mortality. Results: In the pretreatment group, 50 (25.4%) patients were treated with AP and 37 (18.8%) with VKA. The median (interquartile range 25-75) uHG was 19.7 ml/h (2.9-44.8) for AP pretreated patients, 16.2 ml/h (5.1-42.5) for VKA pretreated patients and 8.4 ml/h (2.4-21.8) for non-pretreated patients, P = 0.019. The uHG was higher in patients with very-early [42.1 ml/h (20.1-79.6)] and total 3-month mortality [28.0 ml/h (15.8-52.5)] compared with survivors [3.9 ml/h (1.5-10.4)], P < 0.0001. Adjusted by ICH severity and previous functional status, uHG was an independent factor related to very-early (P = 0.028) and total 3-month mortality (P = 0.014). Conclusions: Patients pretreated with antithrombotics have much higher uHG, which would explain the increased mortality in these patients compared to untreated patients. [ABSTRACT FROM AUTHOR]

Background and purpose Epilepsy has been associated with cardiovascular comorbidity. Risk prediction equations are the standard tools in primary prevention of cardiovascular disease. Our aim was to compare the prevalence of cardiovascular risk factors ( CVRFs), cardiovascular risk and statin use in people with epilepsy ( PWE) and the general population. Methods The CVRFs and cardiovascular risk score were compared between 815 PWE from an outpatient register and 5336 participants from a general population cohort. Results People with epilepsy had less hypertension (43.3% vs. 50.4%), less diabetes (15.8% vs. 19.2%), more dyslipidemia (40.2% vs. 34.6%) and lower cardiovascular risk than the general population ( P < 0.01). No etiology was associated with a worse CVRF profile or higher cardiovascular risk. Patients taking enzyme-inducing antiepileptic drugs ( EIAEDs) had more dyslipidemia than the general population (41.6% vs. 34.6%) but similar cardiovascular risk. Independently of risk or CVRFs, PWE had 60% more probability of receiving statins than the general population. Conclusions People with epilepsy had more dyslipidemia, related to EIAEDs, and lower cardiovascular risk but still took more statins than the general population. Physicians should use clinical judgement to decide on further treatment of CVRFs in PWE who are below the recommended risk threshold for treatment and should consider lipid abnormalities a potential side-effect of EIAEDs. Other therapy options may need to be evaluated before starting lipid-lowering treatment. [ABSTRACT FROM AUTHOR]

Aims To perform a comparative study for determining the optimum culture method (direct plating or enrichment) and medium (ampicillin dextrin agar ( ADA), starch ampicillin agar ( SAA), bile salts irgasan brilliant green modified ( BIBG-m)) for recovering Aeromonas species from water and shellfish samples. Methods and Results By direct culture, Aeromonas was detected in 65% (13/20) of the water samples and in 54·5% (6/11) of the shellfish samples. However, when a pre-enrichment step was included, the number of positive water samples increased to 75% (15/20) and the ones of shellfish to 90·1% (10/11). The enriched culture significantly favoured ( P < 0·05) the isolation of Aeromonas allosaccharophila from water, Aeromonas salmonicida from shellfish and Aeromonas caviae from both types of samples. The most specific ( P < 0·05) culture medium for detecting Aeromonas from water was ADA. However, no differences were observed in the case of shellfish samples ( P > 0·05). Isolation of Aeromonas media from water was favoured ( P < 0·05) in the ADA medium, while SAA enhanced ( P < 0·05) the isolation of Aer. salmonicida from shellfish. Conclusions The culture method and medium used influenced the recovery of some Aeromonas species from water and shellfish samples. Significance and Impact of the Study This fact should be considered in future prevalence studies to avoid overestimating the above mentioned Aeromonas species. [ABSTRACT FROM AUTHOR]

The fundamentals for the topological classification of periodic orientation-preserving self-homeomorphisms of a closed orientable topological surface X of genus $$g \ge 2$$ have been established, by Nielsen, in the thirties of the last century. Here we consider two concepts related to this classification; rigidity and weak rigidity. A cyclic action G of order N on X is said to be topologically rigid if any other cyclic action of order N on X is topologically conjugate to it. If this assertion holds for arbitrary other action but having, in addition, the same orbit genus and the same structure of singular orbits, then G is said to be weakly topologically rigid. We give a precise description of rigid and weakly rigid cyclic quasi-platonic actions which mean actions having three singular orbits and for which X / G is a sphere. [ABSTRACT FROM AUTHOR]

In this work we apply the discrete element method (DEM) to model packings of spherocylinders. The so-called composite spheres method was used to construct particles of different aspect ratio, surface shape and curvature. Using the DEM we probe in detail the effect of particle curvature and surface shape on packing morphology and stress transmission. We find that particle shape has a remarkable influence on both the packing morphology (quantified via the solid fraction, particle orientation distribution and radial distribution function) and stress transmission. Specifically, elongated particles have a high preference for horizontal alignment, whereas an increasing particle curvature leads to a more continuous (i.e. less discrete) particle orientation distribution. Generally, we observe that rough and curved particles have a stronger tendency for interlocking (in particular for small particle aspect ratios, i.e. $$AR=2$$ and 3) leading to the formation of dense packing structures. In addition packings of rough and curved particles of small aspect ratios favor stress transmission in the gravitational direction, thus, limiting stress saturation with depth. [ABSTRACT FROM AUTHOR]

In this work, we examine theoretically the cooling dynamics of binary mixtures of spheres and rods. To this end, we introduce a generalized mean field analytical theory, which describes the free cooling behavior of the mixture. The relevant characteristic time scale for the cooling process is derived, depending on the mixture composition and the aspect ratio of the rods. We simulate mixtures of spherocylinders and spheres using a molecular dynamics algorithm implemented on graphics processing unit (GPU) architecture. We systematically study mixtures composed of spheres and rods with several aspect ratios and varying the mixture composition. A homogeneous cooling state, where the time dependence of the system's intensive variables occurs only through a global granular temperature, is identified. We find cooling dynamics in excellent agreement with Haff's law, when using an adequate time scale. Using the scaling properties of the homogeneous cooling dynamics, we estimated numerically the efficiency of the energy interchange between rotational and translational degrees of freedom for collisions between spheres and rods. [ABSTRACT FROM AUTHOR]

We present experimental and numerical results for particle alignment and stress distribution in packings of faceted particles deposited in a small-scale bi-dimensional silo. First, we experimentally characterize the deposits' morphology in terms of the particles' aspect ratio and feeding rate. Then we use the experimental results to validate our discrete element method (DEM) based on spheropolygons. After achieving excellent agreement, we use contact forces and fabric provided by the simulations to calculate the coarse-grained stress tensor. For low feeding rates, square particles display a strong tendency to align downwards, i.e., with a diagonal parallel to gravity. This morphology leads to stress transmission towards the walls, implying a quick development of pressure saturation, in agreement with the Janssen effect. When the feed rate is increased, both the disorder and the number of horizontal squares in the silo increase, hindering the Janssen effect. Conversely, for elongated particles the feed rate has a weak effect on the final deposit properties. Indeed, we always observe highly ordered structures of horizontal rods where the stress is transmitted mainly in the vertical direction. [ABSTRACT FROM AUTHOR]

The resistivity structure of the Tenerife geothermal system has been determined by the 3-D inversion of data from different magnetotelluric surveys. In this paper, the ocean and topography effects on the magnetotelluric data were investigated by constructing a 3-D conceptual geoelectrical model of the island. The study showed that these effects should be taken into account in order to obtain a reliable subsurface model of the island. Data from 148 sites were used during three-dimensional inversion. The most interesting feature in the final geoelectrical model of the geothermal system is a low resistivity structure (<10 Ωm) above the resistive core of the system. The low resistivity structure has been interpreted as a hydrothermal clay alteration cap typically generated in the conventional geothermal systems. The resistivity model has been correlated with a recent seismic velocity model, showing that a low resistivity structure surrounds an area with high P wave velocity and medium-high resistivity. This medium-high resistivity area can be associated with a slowly solidified magma and, therefore, with a hotter part of the geothermal system. [ABSTRACT FROM AUTHOR]

In this work, we examine a quasi-2D silo that clogs due to the spontaneous formation of stable arches. We validate a numerical scheme comparing the morphology of clogging arches with previous experimental findings. Additionally, we inspect the forces that act on particles, both on those in the bulk of the silo as well as those belonging to the arches formed above the outlet. In the silo, we have found that normal forces are higher close to the wall, in contrast to the central part of the silo, where normal forces are notably lower. Besides, it is revealed that normal forces on particles belonging to the clogging arches are significantly larger than in their surroundings. In a particle of the arch, the magnitude of the force strongly depends on the angle subtended from its center to the contact points with its two neighbors in the arch. Indeed, for angles exceeding $$180^{\circ }$$ , the larger the angle, the lower the normal force and the higher the tangential one. On the contrary, for smaller angles the behavior is reversed, so the normal forces increase with the angle. Finally, we present a comparison of the normal and tangential force distributions for the particles within the arch and in the bulk. All this shows the special nature of the forces developed in clogging arches, which suggests that direct extrapolations of bulk properties should not be taken for granted. [ABSTRACT FROM AUTHOR]

A real algebraic curve of genus g is a pair (S,〈 τ 〉), where S is a closed Riemann surface of genus g and τ: S → S is a symmetry, that is, an anti-conformal involution. A Schottky uniformization of (S,〈 τ 〉) is a tuple (Ω,Γ,P:Ω → S), where Γ is a Schottky group with region of discontinuity Ω and P:Ω → S is a regular holomorphic cover map with Γ as its deck group, so that there exists an extended Möbius transformation $\widehat{\tau}$ keeping Ω invariant with P o $\widehat{\tau}$=τ o P. The extended Kleinian group K=〈 Γ, $\widehat{\tau}$〉 is called an extended Schottky groups of rank g. The interest on Schottky uniformizations rely on the fact that they provide the lowest uniformizations of closed Riemann surfaces. In this paper we obtain a structural picture of extended Schottky groups in terms of Klein–Maskit's combination theorems and some basic extended Schottky groups. We also provide some insight of the structural picture in terms of the group of automorphisms of S which are reflected by the Schottky uniformization. As a consequence of our structural description of extended Schottky groups, we get alternative proofs to results due to Kalliongis and McCullough (J. Kalliongis and D. McCullough, Orientation-reversing involutions on handlebodies, Trans. Math. Soc. 348(5) (1996), 1739–1755) on orientation-reversing involutions on handlebodies. [ABSTRACT FROM PUBLISHER]

It is widely recognized that Aeromonas infections produce septicaemia, and ulcerative and haemorrhagic diseases in fish, causing significant mortality in both wild and farmed freshwater and marine fish species that damage the economics of the aquaculture sector. The descriptions of the complete genomes of Aeromonas species have allowed the identification of an important number of virulence genes that affect the pathogenic potential of these bacteria. This review will focus on the most relevant information derived from the available Aeromonas genomes in relation to virulence and on the diverse virulence factors that actively participate in host adherence, colonization and infection, including structural components, extracellular factors, secretion systems, iron acquisition and quorum sensing mechanisms. [ABSTRACT FROM AUTHOR]

We report numerical results of effective attractive forces on the packing properties of two-dimensional elongated grains. In deposits of non-cohesive rods in 2D, the topology of the packing is mainly dominated by the formation of ordered structures of aligned rods. Elongated particles tend to align horizontally and the stress is mainly transmitted from top to bottom, revealing an asymmetric distribution of local stress. However, for deposits of cohesive particles, the preferred horizontal orientation disappears. Very elongated particles with strong attractive forces form extremely loose structures, characterized by an orientation distribution, which tends to a uniform behavior when increasing the Bond number. As a result of these changes, the pressure distribution in the deposits changes qualitatively. The isotropic part of the local stress is notably enhanced with respect to the deviatoric part, which is related to the gravity direction. Consequently, the lateral stress transmission is dominated by the enhanced disorder and leads to a faster pressure saturation with depth. [ABSTRACT FROM AUTHOR]

We present experimental and numerical results of the effect that a partial discharge has on the morphological and micro-mechanical properties of non-spherical, convex particles in a silo. The comparison of the particle orientation after filling the silo and its subsequent partial discharge reveals important shear-induced orientation, which affects stress propagation. For elongated particles, the flow induces an increase in the packing disorder which leads to a reduction of the vertical stress propagation developed during the deposit generated prior to the partial discharge. For square particles, the flow favors particle alignment with the lateral walls promoting a behavior opposite to the one of the elongated particles: vertical force transmission, parallel to gravity, is induced. Hence, for elongated particles the flow developed during the partial discharge of the silo leads to force saturation with depth whereas for squares the flow induces hindering of the force saturation observed during the silo filling. [ABSTRACT FROM AUTHOR]

Abstract: (Neuro)cysticercosis is an important zoonotic disease caused by infection with Taenia solium metacestode larvae. Existing immunodiagnostic techniques detect antibodies and circulating antigens (Ag) in serum and cerebrospinal fluid (CSF). Blood/CSF collection is an invasive procedure associated with blood-borne infections and is often not well accepted by communities. Detection of circulating Ag in urine has been suggested as an alternative, however this has been evaluated in clinical settings only. The aim of the present study was to evaluate the performance of a urine Ag-ELISA under field conditions. Paired serum and urine samples were obtained from participants in endemic areas of Ecuador (n =748) and Zambia (n =690) and were subjected to a monoclonal antibody-based Ag-ELISA. Calculation of positive and negative agreement indices (AI) showed better agreement in the negative direction both for Ecuadorian and Zambian samples (AI of 93.1 and 86.8, respectively). Using a Bayesian approach to determine the test characteristics, similar sensitivities were obtained for serum and urine Ag detection, whereas a decreased specificity was determined for the urine Ag-ELISA with a lower specificity (78.6%) for Zambian samples than for Ecuadorian samples (88.4%). This study indicates a higher specificity for the serum test under field conditions and promotes further research to improve the urine test. [Copyright &y& Elsevier]

A knowledge-based expert system (KBES) is proposed for the scheduling of an energy storage system (ESS) installed in a wind-diesel isolated power system. The program optimises the cost of operation by determining the diesel generation and the charging/discharging cycles of the storage system from the wind and load profiles one hour in advance. The rules created aim to minimise the use of the dump load normally associated with diesel operation. The results are compared to an offline optimisation algorithm applied to the same power system and ESS size that has a 24-h lookahead. The results obtained show that by minimising the energy wasted through the dump load with the use of the ESS and KBES controller, the required diesel generation is reduced, therefore reducing operation costs and emissions. [ABSTRACT FROM AUTHOR]

Brain ischemic lesions identified by diffusion-weighted imaging (DWI) have been shown to predict high risk of early future ischemic events in patients with transient ischemic attacks and minor stroke. The aim of this study is to analyze different brain MRI–DWI patterns in patients with mild-moderate stroke to define acute patterns related with a higher risk of stroke recurrence in long-term follow-up (from 6 to 36 months). Retrospective review of case series from a prospective stroke record including 253 patients with mild-moderate stroke (NIHSS from 1 to 7) and acute MRI–DWI lesions. MRI–DWI lesions were analyzed to determine clinically relevant lesions, based on the number, location, age and affected arterial territories. We defined three patterns: (1) multiple versus single lesions; (2) single deep versus single cortical lesions; and (3) single lesions versus multiple lesions affecting different arterial territories and/or of different age. The impact of these patterns on recurrence was analyzed by Cox regression analysis. 38 patients (15.0%) suffered a recurrence. Univariate analysis showed the risk of recurrence for each pattern. Pattern 1: patients with multiple lesions had greater risk of recurrence than those with single lesions (28.2 vs. 9.9%; OR: 3.75 (95% CI: 1.76–7.27), p < 0.0001). Pattern 2: patients with single cortical lesions had higher risk than those with deep lesions (14.3 vs. 6.7% OR: 2.33 (95% CI: 0.86–6.33), p < 0.089). Pattern 3: patients with multiple DWI in different territories or different age had the highest recurrence rate (30.6%), OR: 4.01 (95% CI: 1.70–9.47), p < 0.001, compared to patients with single lesions. Cox regression analysis adjusted by possible confounders, showed that for pattern 1 the OR for recurrence was 2.49 (95% CI: 1.27–4.89), p = 0.008; for pattern 2, OR:1.99 (95% CI: 0.74–5.37), p = 0.17; for pattern 3, OR: 2.85 (95% CI: 1.31–6.15), p = 0.008. Brain MRI–DWI patterns assessed in the acute phase of mild-moderate stroke are useful to identify those patients at high risk of recurrence. [ABSTRACT FROM AUTHOR]

Oral Diseases (2010) 16, 388–395 Objectives: Periodontal disease is characterized by an increased collagen metabolism. Although membrane type-1 matrix metalloproteinase (MT1-MMP) plays a critical role in collagen degradation, its involvement in human periodontitis remains to be determined. Methods: MT1-MMP and TIMP-2 expression and distribution were evaluated in gingival tissue samples derived from 10 healthy and 12 periodontitis-affected human subjects. MT1-MMP and TIMP-2 expression were assessed through Western-blot of tissue homogenates. The main cell types involved in MT1-MMP and TIMP-2 production were evaluated by means of immunohistochemistry. Results: Both MT1-MMP and TIMP-2 were significantly increased in periodontitis-affected gingival tissues when compared to healthy gingiva. Moreover, the balance between MT1-MMP and its inhibitor TIMP-2 was altered in periodontitis-affected tissues, suggesting an imbalance in this proteolytic axis. Immunohistochemistry demonstrated the expression of MT1-MMP in fibroblasts and macrophages in gingival tissues. MT1-MMP was detected in cells in close association with the gingival collagen matrix. TIMP-2 expression was identified in fibroblasts, macrophages and epithelial cells. Conclusions: Our observations show an increased expression of MT1-MMP and TIMP-2 in periodontitis-affected gingival tissues. The altered balance between these two molecular mediators of collagen remodeling suggests their involvement in human periodontal disease. [ABSTRACT FROM AUTHOR]

A geometric orbifold of dimension d is the quotient space S = X/K, where ( X,G) is a geometry of dimension d and K < G is a co-compact discrete subgroup. In this case {ie38-01} is called the orbifold fundamental group of S. In general, the derived subgroup K’ of K may have elements acting with fixed points; i.e., it may happen that the homology cover MS = X/K’ of S is not a geometric manifold: it may have geometric singular points. We are concerned with the problem of deciding when K′ acts freely on X; i.e., when the homology cover MS is a geometric manifold. In the case d = 2 a complete answer is due to C. Maclachlan. In this paper we provide necessary and sufficient conditions for the derived subgroup S to act freely in the case d = 3 under the assumption that the underlying topological space of the orbifold K is the 3-sphere S3. [ABSTRACT FROM AUTHOR]

Background Causality assessment in hepatotoxicity is challenging. The current standard liver-specific Council for International Organizations of Medical Sciences/Roussel Uclaf Causality Assessment Method scale is complex and difficult to implement in daily practice. The Naranjo Adverse Drug Reactions Probability Scale is a simple and widely used nonspecific scale, which has not been specifically evaluated in drug-induced liver injury. Aim To compare the Naranjo method with the standard liver-specific Council for International Organizations of Medical Sciences/Roussel Uclaf Causality Assessment Method scale in evaluating the accuracy and reproducibility of Naranjo Adverse Drug Reactions Probability Scale in the diagnosis of hepatotoxicity. Methods Two hundred and twenty-five cases of suspected hepatotoxicity submitted to a national registry were evaluated by two independent observers and assessed for between-observer and between-scale differences using percentages of agreement and the weighted kappa (κw) test. Results A total of 249 ratings were generated. Between-observer agreement was 45% with a κw value of 0.17 for the Naranjo Adverse Drug Reactions Probability Scale, while there was a higher agreement when using the Council for International Organizations of Medical Sciences/Roussel Uclaf Causality Assessment Method scale (72%, κw: 0.71). Concordance between the two scales was 24% (κw: 0.15). The Naranjo Adverse Drug Reactions Probability Scale had low sensitivity (54%) and poor negative predictive value (29%) and showed a limited capability to distinguish between adjacent categories of probability. Conclusion The Naranjo scale lacks validity and reproducibility in the attribution of causality in hepatotoxicity. [ABSTRACT FROM AUTHOR]