Universal features of annealing and aging in compaction of granular piles.

This paper links the nonequilibrium glassy relaxation behavior of otherwise athermal granular materials to those of thermally activated glasses. Thus, it demonstrates a much wider universality among complex glassy materials out of equilibrium. Our three-dimensional molecular dynamics simulations, fully incorporating friction and inelastic collisions, are designed to reproduce experimental behavior of tapped granular piles. A simple theory based on a dynamics of records explains why the typical phenomenology of annealing and aging after a quench should extend to such granular matter, activated by taps, beyond the more familiar realm of polymers, colloids, and magnetic materials that all exhibit thermal fluctuations.

Implementation of a pre-hospital network favoring primary angioplasty in STEMI to reduce mortality: the Algarve Project.

OBJECTIVE: To analyze the impact of reperfusion by either primary percutaneous coronary intervention (PPCI) or fibrinolysis, and mortality rates of a pre-hospital fast-track network for treating patients with ST-elevation myocardial infarction (STEMI). METHODS AND RESULTS: A pre-hospital network for STEMI patients, designated the Green Lane for Acute Myocardial Infarction (GL-AMI), has been implemented in the southern region of Portugal --the Algarve Project. We performed an observational study based on a prospective registry of 1338 patients admitted to Faro Hospital between 2004 and 2009, classified in two groups according to the method of admission: emergency department group (EDG) and GL-AMI group (GLG). More patients from GLG were reperfused (p < 0.0001). PPCI was the preferred method of reperfusion, 73.1% in GLG and 45.3% in EDG. Time delays were significantly shorter in GLG, except for pre-hospital delay: pre-hospital delay (p = 0.11); door-to-needle (p < 0.0001); door-to-balloon (p < 0.0001); and delay between symptoms and reperfusion (p < 0.0001). In-hospital mortality (4.3% vs 9.2%, p = 0.0007) and 6-month mortality (6.3% vs 13.8%, p < 0.0001) were significantly lower in GLG. CONCLUSIONS: The Algarve Project significantly reduced the time delay between onset of symptoms and reperfusion, significantly increased the rate of reperfusion, and significantly reduced in-hospital and six-month mortality.

Density fluctuations in granular piles traversing the glass transition: A grain-scale characterization via the internal energy.

The transition into a glassy state of the ensemble of static, mechanically stable configurations of a tapped granular pile is explored using extensive molecular dynamics simulations. We show that different horizontal subregions ("layers") along the height of the pile traverse this transition in a similar manner but at distinct tap intensities. We supplement the conventional approach based purely on properties of the static configurations with investigations of the grain-scale dynamics by which the tap energy is transmitted throughout the pile. We find that the effective energy that particles dissipate is a function of each particle's location in the pile and, moreover, that its value plays a distinctive role in the transformation between configurations. This internal energy provides a "temperature-like" parameter that allows us to align the transition into the glassy state for all layers, as well as different annealing schedules, at a critical value.

[Endomyocardial fibrosis with massive calcification of the left ventricle]. / Fibrose endomiocárdica com calcificação maciça do ventrículo esquerdo.

Endomyocardial fibrosis is a rare disease, endemic in tropical countries. It is characterized by fibrosis of the endocardium that can extend to myocardium. Important calcification of the endocardium is rare with only a few cases reported in the literature. We report a case of endomyocardial fibrosis in a european caucasian patient, associated with massive calcification of left ventricle.

Female gender: an independent factor in ST-elevation myocardial infarction.

INTRODUCTION: Cardiovascular disease is the leading cause of death in women. In ST-elevation myocardial infarction (STEMI) in particular, the question has been raised whether specific characteristics of women confer a worse prognosis. OBJECTIVE: To evaluate the differences in STEMI patients between the genders in cardiovascular risk profile, clinical presentation, therapeutic approach and in-hospital and 6-month mortality rates. METHODS: We analyzed 1578 patients admitted consecutively with STEMI during a 7-year period (from January 13, 2002 to December 31, 2008). The patients were divided into two groups according to gender, and compared in terms of baseline clinical and demographic characteristics, pre-hospital and in-hospital delay, clinical presentation on admission, reperfusion therapy, severity of coronary disease and in-hospital and 6-month mortality. RESULTS: Of the 1578 patients, 26% were female. Women were older (by 8 years), and had a higher cardiovascular risk profile. On admission, their clinical presentation was more severe, with a higher frequency of anterior myocardial infarction and acute heart failure symptoms. Women had longer ischemic times and lower rates of reperfusion therapy. Mortality in women was significantly higher than in men, both in-hospital (17.5 vs. 5.3%) and at 6 months (23.5% vs. 8.2%). After adjustment in multivariate analysis, mortality in women remained higher. CONCLUSIONS: The adverse demographic and clinical profile could partially explain the worse prognosis of STEMI in women. This, together with longer pre-hospital delays, led to underuse of reperfusion therapy. Even so, female gender by itself had a negative and independent influence on mortality in STEMI patients.

Fluid-induced fracture into weakly consolidated sand: Impact of confining stress on initialization pressure.

This paper studies the process of fluid injection driven fractures in granular packs where particles are held together by external confining stresses and weak intergrain cohesion. We investigate the process of fracture formations in soft sand confined into a radial Hele-Shaw cell. Two main regimes are well known for fluid injection in soft sand. For low fluid injection pressures it behaves as a solid porous material while for high enough injection pressures grain rearrangement takes place. Grain rearrangements lead to the formation of fluid channels or "fractures," the structure and geometry of which depend on the material and fluid properties. Due to macroscopic grain displacements and the predominant role of dissipative frictional forces in granular system dynamics, these materials do not behave as conventional brittle, linear elastic materials and the transition between these two regimes cannot usually be described using poroelastic models. In this work we investigate the change in the minimum fluid pressure required to start grain mobilization as a function of the confining stresses applied to the system using a spatially resolved computational fluid dynamics-discrete element method numerical model. We show that this change is proportional to the applied stress when the confining stresses can be regarded as uniformly distributed among the particles in the system. A preliminary analytical expression for this change is presented.

Stress inhomogeneity effect on fluid-induced fracture behavior into weakly consolidated granular systems.

We study the effect of stress inhomogeneity on the behavior of fluid-driven fracture development in weakly consolidated granular systems. Using numerical models we investigate the change in fracture growth rate and fracture pattern structure in unconsolidated granular packs (also referred to as soft-sands) as a function of the change in the confining stresses applied to the system. Soft-sands do not usually behave like brittle, linear elastic materials, and as a consequence, poroelastic models are often not applicable to describe their behavior. By making a distinction between "cohesive" and "compressive" grain-grain contact forces depending on their magnitude, we propose an expression that describes the fluid opening pressure as a function of the mean value and the standard deviation of the "compressive stress" distribution. We also show that the standard deviation of this distribution can be related with the extent to which fracture "branches" reach into the material.

In-hospital delay in ST-segment-elevation myocardial infarction after Manchester Triage.

INTRODUCTION: In ST-segment elevation myocardial infarction (STEMI), time to reperfusion influences morbidity and mortality, and reducing in-hospital delay (IHD) continues to be important. Doubts have been expressed whether the Manchester Triage System (MTS) contributes to this objective. OBJECTIVE: To evaluate the effectiveness of the MTS in classifying STEMI patients and its effect on IHD. METHODS: We analyzed 278 patients with STEMI admitted to the Coronary Care Unit through the Emergency Department between January 13 2005 and November 26 2006. The patients were divided into two groups according to their MTS classification: Group A--emergent and very urgent patients; Group B--urgent and standard patients. The two groups were compared in terms of clinical and demographic characteristics, pre-hospital delay (PHD), IHD and door-to-needle (DNT) and door-to-balloon (DBT) times. RESULTS: The mean age of the patients studied was 68 +/- 14 years, and 184 patients (65.7%) were male. Group A comprised 220 patients (79%) and Group B 58 patients (21%). There were no significant differences between the two groups in clinical or demographic characteristics or in PHD. IHD, DNT and DBT were significantly longer in Group B. CONCLUSIONS: 1) Although the majority of STEMI patients were classified as emergent or very urgent, the percentage not classified as such by the MTS was excessively high. 2) This could not be explained by clinical characteristics or by PHD. 3) The incorrect classification by the MTS of patients with STEMI resulted in significantly increased IHD in a large proportion of patients, limiting prompt access to reperfusion therapy.

Comparison of Eye Movement Desensitization Reprocessing and Cognitive Behavioral Therapy as Adjunctive Treatments for Recurrent Depression: The European Depression EMDR Network (EDEN) Randomized Controlled Trial.

Background: Treatment of recurrent depressive disorders is currently only moderately successful. Increasing evidence suggests a significant relationship between adverse childhood experiences and recurrent depressive disorders, suggesting that trauma-based interventions could be useful for these patients. Objectives: To investigate the efficacy of Eye Movement Desensitization and Reprocessing therapy (EMDR) in addition to antidepressant medication (ADM) in treating recurrent depression. Design: A non-inferiority, single-blind, randomized clinical controlled trial comparing EMDR or CBT as adjunctive treatments to ADM. Randomization was carried out by a central computer system. Allocation was carried out by a study coordinator in each center. Setting: Two psychiatric services, one in Italy and one in Spain. Participants: Eighty-two patients were randomized with a 1:1 ratio to the EMDR group (n = 40) or CBT group (n = 42). Sixty-six patients, 31 in the EMDR group and 35 in the CBT group, were included in the completers analysis. Intervention: 15 ± 3 individual sessions of EMDR or CBT, both in addition to ADM. Participants were followed up at 6-months. Main outcome measure: Rate of depressive symptoms remission in both groups, as measured by a BDI-II score <13. Results: Sixty-six patients were analyzed as completers (31 EMDR vs. 35 CBT). No significant difference between the two groups was found either at the end of the interventions (71% EMDR vs. 48.7% CBT) or at the 6-month follow-up (54.8% EMDR vs. 42.9% CBT). A RM-ANOVA on BDI-II scores showed similar reductions over time in both groups [F(6,59) = 22.501, p < 0.001] and a significant interaction effect between time and group [F(6,59) = 3.357, p = 0.006], with lower BDI-II scores in the EMDR group at T1 [mean difference = -7.309 (95% CI [-12.811, -1.806]), p = 0.010]. The RM-ANOVA on secondary outcome measures showed similar improvement over time in both groups [F(14,51) = 8.202, p < 0.001], with no significant differences between groups [F(614,51) = 0.642, p = 0.817]. Conclusion: Although these results can be considered preliminary only, this study suggests that EMDR could be a viable and effective treatment for reducing depressive symptoms and improving the quality of life of patients with recurrent depression. TRIAL REGISTRATION: ISRCTN09958202.

Sevoflurane-induced arrhythmia in healthy adult.

Inhalatory anesthetic agents are frequently used for anesthesia maintenance. Sevoflurane is considered one of the safest regarding its cardiac effects. We report a case of a cardiac arrhythmia induced by sevoflurane in an otherwise healthy adult and discuss sevoflurane's cardiac effects.

Cardiogenic shock: Inotropes and vasopressors. / Choque cardiogénico ­ fármacos inotrópicos e vasopressores.

Cardiogenic shock is characterized by a decrease in myocardial contractility, and presents a high mortality rate. Inotropic and vasopressor agents have been recommended and used for several years in the treatment of patients in shock, but they remain controversial. Despite its beneficial effect on myocardial contractility, the side effects of inotropic therapy (arrhythmias and increased myocardial oxygen consumption) may be associated with increased mortality. The pharmacodynamics of different inotropic agents suggest benefits in specific situations, but these differences have not been reflected in reduced mortality in most studies, making it difficult to formulate recommendations. This review integrates data from different studies on the use of inotropes and vasopressors in patients with cardiogenic shock, proposing a therapeutic scheme for the pharmacological treatment of patients in cardiogenic shock according to the patient's hemodynamic profile.

Coronary arteries anomalous aortic origin on a computed tomography angiography population: prevalence, characteristics and clinical impact.

Anomalous aortic origin of coronary arteries (AAOCA) is one of the most frequent causes of cardiovascular sudden death among the young population. We aimed to determine the prevalence and anatomic characteristics of AAOCA in a population referred to computed tomography angiography (CTA) and to describe the clinical prognosis of these findings at middle term follow-up. From a total of 3539 CTA, 53 were found to have AAOCA. This population was compared to an age and gender matched control group (n = 106) from the same CTA list. A telephone follow-up to determine cardiac events was conducted, with a mean follow-up of 45.9 ± 28.2 months. Prevalence of AAOCA was 1.5 %. The most common AAOCA was an origin of the right coronary artery (RCA) from the left coronary sinus, followed by an origin of the left circumflex artery (LCX) arising from the right coronary sinus. All patients with an anomalous origin of the RCA had an interarterial course. Four additional patients were found to have an interarterial course: 1 with an anomalous origin of LCX and 3 with an anomalous origin of the left main coronary artery (LMCA). At follow-up there were 33 (21.2 %) cardiac events, 9 (17.6 %) on the AAOCA group and 24 (22.9 %) on the control group (p = 0.46). Cardiac events and cardiovascular deaths were not related to any particular AAOCA or to interarterial courses. Among an adult population referred to CTA, AAOCA were not related with worse middle term prognosis when compared to an age- and gender- matched population.

Congenital left ventricular apical aneurysm presenting as ventricular tachycardia.

The authors present the case of a 34-year-old male patient seen in our department due to palpitations. On the electrocardiogram monomorphic ventricular tachycardia (VT) was documented, treated successfully with amiodarone. The subsequent study revealed a normal echocardiogram and an apical aneurysm of the left ventricle on magnetic resonance imaging, confirmed by computed tomography coronary angiography that also excluded coronary disease. He underwent an electrophysiological study to determine the origin of the VT and to perform catheter ablation using electroanatomical mapping. VT was induced and radiofrequency applications were performed in the left ventricular aneurysm area. VT was no longer inducible, with acute success. Despite this it was decided to implant a subcutaneous implantable cardioverter-defibrillator (ICD). Eight months after the ablation the patient was admitted again due to VT, treated by the ICD.

Relevance of system size to the steady-state properties of tapped granular systems.

We investigate the steady-state packing fraction ϕ and force moment tensor Σ of quasi-two-dimensional granular columns subjected to tapping. Systems of different height h and width L are considered. We find that ϕ and Σ, which describe the macroscopic state of the system, are insensitive to L for L>50d (with d the grain diameter). However, results for granular columns of different heights cannot be conciliated. This suggests that comparison between results of different laboratories on this type of experiments can be done only for systems of same height. We show that a parameter ɛ=1+(Aω)2/(2gh), with A and ω the amplitude and frequency of the tap and g the acceleration of gravity, can be defined to characterize the tap intensity. This parameter is based on the effective flight of the granular bed, which takes into account the h dependency. When ϕ is plotted as a function of ɛ, the data collapses for systems of different h. However, this parameter alone is unable to determine the steady state to be reached since different Σ can be observed for a given ɛ if different column heights are considered.

Changes in referral protocols for cardiac surgery: do financial considerations come at a cost?

INTRODUCTION AND OBJECTIVES: The aim of this study was to determine whether changes to referral protocols for cardiac surgery have had an impact on waiting times, hospitalizations and mortality during the waiting period and during the first year of follow-up after surgery. METHODS: In this retrospective study of patients referred for cardiac surgery between January 1, 2008 and September 30, 2014, the study population was divided into two groups: those referred before (group A, January 1, 2008 to August 31, 2011) and after (group B, September 1, 2011 to September 30, 2014) the change in referral protocols. A telephone follow-up was conducted. RESULTS: There were 864 patients referred for cardiac surgery, 557 in group A and 307 in group B. Patient characteristics were similar between groups. The mean waiting time for surgery was 10.6±18.5 days and 55.7±79.9 days in groups A and B, respectively (p=0.00). During the waiting period two patients (0.4%) were hospitalized in group A and 28 (9.1%) in group B (p=0:00); mortality was, respectively, 0% and 2.3% (p=0.00). During one-year follow-up 12.8% of group A patients and 16% of group B patients were hospitalized. Cardiovascular mortality in this period was around 5% in both groups (p>0.05). CONCLUSION: Changes to referral protocols for cardiac surgery had an impact on waiting times, on the number of hospitalizations and on mortality in this period.

Experimental proof of faster-is-slower in systems of frictional particles flowing through constrictions.

The "faster-is-slower" (FIS) effect was first predicted by computer simulations of the egress of pedestrians through a narrow exit [D. Helbing, I. J. Farkas, and T. Vicsek, Nature (London) 407, 487 (2000)]. FIS refers to the finding that, under certain conditions, an excess of the individuals' vigor in the attempt to exit causes a decrease in the flow rate. In general, this effect is identified by the appearance of a minimum when plotting the total evacuation time of a crowd as a function of the pedestrian desired velocity. Here, we experimentally show that the FIS effect indeed occurs in three different systems of discrete particles flowing through a constriction: (a) humans evacuating a room, (b) a herd of sheep entering a barn, and (c) grains flowing out a 2D hopper over a vibrated incline. This finding suggests that FIS is a universal phenomenon for active matter passing through a narrowing.

Clogging transition of many-particle systems flowing through bottlenecks.

When a large set of discrete bodies passes through a bottleneck, the flow may become intermittent due to the development of clogs that obstruct the constriction. Clogging is observed, for instance, in colloidal suspensions, granular materials and crowd swarming, where consequences may be dramatic. Despite its ubiquity, a general framework embracing research in such a wide variety of scenarios is still lacking. We show that in systems of very different nature and scale -including sheep herds, pedestrian crowds, assemblies of grains, and colloids- the probability distribution of time lapses between the passages of consecutive bodies exhibits a power-law tail with an exponent that depends on the system condition. Consequently, we identify the transition to clogging in terms of the divergence of the average time lapse. Such a unified description allows us to put forward a qualitative clogging state diagram whose most conspicuous feature is the presence of a length scale qualitatively related to the presence of a finite size orifice. This approach helps to understand paradoxical phenomena, such as the faster-is-slower effect predicted for pedestrians evacuating a room and might become a starting point for researchers working in a wide variety of situations where clogging represents a hindrance.

Evolution of pressure profiles during the discharge of a silo.

We report measurements of the pressure profile in the outlet plane of a discharging silo. We observe that, whatever the preparation of the granular system, a dynamic Janssen effect is at play: the apparent mass of the grains (i.e., the part of their mass sustained by the base) is significantly smaller than their actual mass because of the redirection of the weight to the lateral wall of the container. The pressure profiles reveal a significant decrease in pressure in the vicinity of the outlet as the system discharges, whereas the flow rate remains constant. The measurements are thus a direct experimental proof that the flow rates of granular material through an aperture are not controlled by the local stress conditions.

Towards a relevant set of state variables to describe static granular packings.

We analyze, experimentally and numerically, the steady states, obtained by tapping, of a two-dimensional granular layer. Contrary to the usual assumption, we show that the reversible (steady state branch) of the density-acceleration curve is nonmonotonous. Accordingly, steady states with the same mean volume can be reached by tapping the system with very different intensities. Simulations of dissipative frictional disks show that equal volume steady states have different values of the force moment tensor. Additionally, we find that steady states of equal stress can be obtained by changing the duration of the taps; however, these states present distinct mean volumes. These results confirm previous speculations that the volume and the force moment tensor are both needed to describe univocally equilibrium states in static granular assemblies.