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We consider a generalized version of Carrier-Sense Multiple Access (CSMA), where the contention window size is a constant and the back-off probability distribution can be varied. We address the optimization of a weighted throughput metric, identifying the optimal back-off Probability Density Function (PDF). We give a simple fixed-point algorithm to compute the optimal PDF and prove that the solution is unique. The weighted throughput definition caters for aspects other than the mere channel utilization. It reduces to plain utilization (normalized throughput) when all weights are equal to 1. We also reconnect our result to the classic analysis of saturated non-persistent CSMA, as introduced in the seminal paper by Tobagi and Kleinrock, proving formally that the modeling assumptions of that work, that lead to a Geometric PDF of back-off, actually correspond to the throughput-optimal choice, provided that the ratio of the Geometric PDF is suitably chosen.

In this article, a cooperative multitechnology simultaneous localization and signal mapping (CM-SLASM) technique is proposed to improve the signal map accuracy and to build on-the-fly a signal map to be used also in indoor environments where conditions can change over time. Moreover, the CM-SLASM combines wireless fidelity (WiFi), ultra wideband (UWB), and light detection and ranging (LIDAR) signals to improve positioning estimation by sharing information and cooperation among vehicles through vehicle-to-vehicle (V2V) communication links. In particular, LIDAR-based distance between vehicles is shared among neighbor vehicles to improve the vehicle positioning estimated by an extended Kalman filter (EKF) where WiFi fingerprinting is combined with UWB multilateration. The overall solution where EKF estimation allows to building of more precise signal MAP is validated by simulation in a defined indoor scenario where vehicles equipped with different percentages of LIDAR, and different quantities of UWB and WiFi emitters have been considered. The proposed strategy has been validated through an extensive simulation campaign in various scenarios of interest and through a real-world experiment conducted in a laboratory test environment.

Many studies in literature have shown that the bandwidth of an ongoing flow can dynamically change during multimedia sessions and an efficient bandwidth prediction scheme must be employed in order to guarantee the needed Quality of Service. Many contributions in literature focused on some specific reservation schemes for cellular systems, 3G/4G/5G networks, WLAN and so on. However, few of them exploited the trade-off between resource prediction error and bandwidth wastage through a general prediction technique based on the analysis of Cell Stay Time, on the direction probabilities of hand-in and hand-out events of mobile nodes among wireless cells and on the resource over-provisioning due to the uncertain mobility patterns. Our proposed scheme is based on the stochastic computation and characterization of user movements and it is absolutely general. Two novel metrics such as prediction error e and resource wastage u are defined. Moreover, predictive reservation schemes, admission prediction and resource wastage probabilistically associated to the stochastic hand-in/hand-out movement directions are proposed, with an optimization problem for the optimal pre-reservation of bandwidth in wireless system. A threshold-based reservation scheme has been considered as a practical case and it has been evaluated in terms of reservation prediction errors and resource wastage, to prove the practical effectiveness and consistence of the defined theoretical bounds.

Pregnancy loss is often caused by chromosomal abnormalities of the conceptus. The prevalence of these abnormalities and the allocation of (ab)normal cells in embryonic and placental lineages during intrauterine development remain elusive. In this study, we analyzed 1,745 spontaneous pregnancy losses and found that roughly half (50.4%) of the products of conception (POCs) were karyotypically abnormal, with maternal and paternal age independently contributing to the increased genomic aberration rate. We applied genome haplarithmisis to a subset of 94 pregnancy losses with normal parental and POC karyotypes. Genotyping of parental DNA as well as POC extra-embryonic mesoderm and chorionic villi DNA, representing embryonic and trophoblastic tissues, enabled characterization of the genomic landscape of both lineages. Of these pregnancy losses, 35.1% had chromosomal aberrations not previously detected by karyotyping, increasing the rate of aberrations of pregnancy losses to 67.8% by extrapolation. In contrast to viable pregnancies where mosaic chromosomal abnormalities are often restricted to chorionic villi, such as confined placental mosaicism, we found a higher degree of mosaic chromosomal imbalances in extra-embryonic mesoderm rather than chorionic villi. Our results stress the importance of scrutinizing the full allelic architecture of genomic abnormalities in pregnancy loss to improve clinical management and basic research of this devastating condition.

Many essential/beneficial elements including Ca, Mg, Sr, B, and F−play an important role in bone health. While elevated levels of F−are known to cause adverse health effects on bone, variations of these elements in nails that can be influenced by F−toxicity are unclear. This study aims to assess the relationship between the concentrations of Ca, Mg, Sr, and B in fingernails and bone quality of F−exposed individuals in the Ethiopian Rift Valley. Bone quality was determined using an ultrasonic method that measures the magnitude of speed of sound (SOS) conduction in cortical bones. We collected fingernails of individuals aged 10 to 70 years old (144 males and 123 females) in 25 communities drinking water from wells with F−concentrations ranging from 0.3 to 15.5 mg/L (mean 7 ± 4.7 mg/L). Fluoride concentrations in drinking water were measured using the ion selective electrode (ISE) method. Concentrations of Ca, Mg, Sr, and B in fingernails were measured using Inductively Coupled Plasma Spectrometry (ICP-MS). Mean Ca, Mg, Sr, and B concentrations (mg/kg) in fingernails were 740 ± 425, 98 ± 89, 1.33 ± 1.6, and 0.63 ± 1.2, respectively. Each element was categorized by F−concentrations (mg/L) in drinking water as groups: 1 (< 2), 2 (> 2–6), 3 (> 6–10), and 4 (> 10–15.5). The mean concentrations of these elements in fingernails increased with the increase in F−concentrations in drinking water, and significant differences were observed in the means of groups 1 and 4 for all elements, group 2 for Sr, and group 3 for B. The correlation trends for SOS measurements with these elements in fingernails at different age groups decrease with high F−exposure and the negative associations are more pronounced at older (51–70) ages. These associations suggest F−related bone deterioration in the studied subjects, which is noticeable with the increase in age. The study demonstrates the effect of F−exposure on bone quality, and the studied fingernail elemental variations in populations chronically exposed to F−in drinking water.

Background: Louisiana is ranked among the top 10 states with the highest COVID-19 death rate in the USA, and African Americans (AA) that account 32.2% (1.5 million) of the state’s population have been impacted differentially with higher rates of chronic health conditions such as hypertension, obesity, and diabetes. These conditions can compromise immune systems and increase susceptibility to COVID-19. Prior health disparity and COVID-19 studies in Louisiana are limited to comprehensively evaluate the risk of underlying health conditions on COVID-19 incidence and death in minority communities and thus the study aims to address this research gap. Methods: Negative binomial regression analyses were used to correlate risk factors with COVID-19 incidence and death rates using SAS software. Spatial distribution and burden of COVID-19 incidence and mortality rates were mapped using ArcGIS Pro. Results: We found that AA COVID-19 death was three times higher than other races, and mortality rate was ten times higher in counties with more than 40% AA. Highest AA case and death counts were found in Orleans County; mortality rate in Bienville; and incidence rate in East Feliciana. Hypertension, diabetes, and obesity were significantly correlated with both COVID-19 incidence and mortality rates in AA. Greater odds of incidence and death rates also found in counties with higher AA population density with higher burden of underlying health conditions. Furthermore, living in poverty, being 65 years and older significantly influenced COVID-19 cases and deaths in the state. Conclusions: The study highlights the need to reduce the burden of health disparities in underserved communities, and help to inform the public, scientific communities, and policy makers to plan effective responses to reduce the risks of COVID-19 infection, death, and other potential infectious diseases at the state.

Non-alcoholic fatty liver disease (NAFLD) is the leading cause of chronic liver disease in both adults and children. Along with obesity and metabolic syndrome, genetic predisposition influences the progression of NAFLD. Here, we investigated the effect of lifespan/healthspan-related single nucleotide polymorphisms (SNPs) on metabolically associated fatty liver disease in children. We evaluated the impact of 10 SNPs involved in both human liver/metabolic diseases and healthspan (interleukin-6 [IL-6] rs1800795, antisense non coding RNA in the INK4locus (ANRIL) rs1556516, SH2B3/ATXN2 rs7137828, FURIN rs17514846, TP53 rs1042522, APOC3 rs2542052, KL rs9536314, KL rs9527025, SIRT6 rs107251, FOXO3 rs2802292) on NAFLD-related metabolic and liver features in 177 pediatric patients with biopsy-proven NAFLD, by comparing them to 146 healthy controls. We then applied a multidimensional reduction (MDR) case–control analysis of SNP–SNP interactions, to identify the joint effect of analyzed SNPs in predicting NAFLD and associated features. Discrete SNPs were significantly associated with individual metabolic NAFLD features, but none of them significantly associated with NAFLD diagnosis. By testing potential synergies using the MDR approach, the best combination to diagnose NAFLD (P= 0.0011) resulted in the one encompassing IL-6 rs1800795 and ANRIL rs1556516. Consistently, the risk combinations suggested by SNP–SNP analysis strongly associated with a higher level of fasting plasma blood glucose level (P= 0.024). In conclusion, here we demonstrated a synergic interaction between IL-6 rs1800795 and ANRIL rs1556516 in the diagnosis of NAFLD, and NAFLD-associated hyperglycemia in children. Larger studies are required to confirm our findings and to elucidate mechanisms by which the genetic interaction between these two genes influences healthspan in pediatric NAFLD.

The crystal structure and overall magnetic properties of RE(Fe0.25Co0.75)2Hy with RE = Ho and Er, were analyzed versus y, the hydrogen content. The single phase C15 type compounds, synthesized using cold crucible HF melting, were hydrogenated and controlled using a PCI apparatus. The impact of hydrogen insertion on the cell parameter, the Curie temperature TC and the magnetization saturation were determined. All compounds and hydrides were found to be ferrimagnets, the magnetic moment of RE and 3d elements being opposite since Ho and Er belong to the 2nd row of rare earth elements. Depending on the formula, a typical compensation point was in evidence. The 2nd order character of the ferri ↔ paramagnetic transition was established using the Arrott plot method. Magnetization isotherms vs. magnetic field gives quantified results for the magnetic entropy variation by application of the Maxwell relation. Control of y, the hydrogen content, shows it is interesting for improvement of the MCE of the starting compounds. However increasing y leads to decreased TC at the lowest temperatures, suggesting potential cryogenic uses.

Benefit from carotid revascularization is supposed to be lower in women due to increased periprocedural risks. The aim of this study was to investigate the risk of stroke/death after carotid intervention in women treated within 15 days from last neurological event.

La tuberculosis (TB) en el sistema nervioso central (SNC) es infrecuente, más aún bajo una presentación atípica como la del tuberculoma en placa. El diagnóstico correcto puede ser dificultoso por no incorporarla como posible agente etiológico de tumores intracraneales.

Sex differences in presentation and outcomes of abdominal aortic aneurysms (AAA) with increased mortality rates in women are suggested. This study aimed to assess mortality risk after repair of ruptured AAA (rAAA) in women in the endovascular abdominal aortic repair (EVAR) era.

A 50-year-old man with chronic pancreatitis was admitted to hospital with increasing midabdominal pain, vomiting and weakness. His history included alcohol abuse, gastric resection and pancreatic pseudocyst. His hemoglobin level [...]

TiVCr alloys known for their potentially large hydrogen uptake were formulated as (TiCr1.8)100-xVx in order to quantify the impact of vanadium concentration. Parallel to this series of pure ternary, a 2nd ones was synthesized with 4 at.% of Zr7Ni10 addition. Electrochemical charging with hydrogen reveals a fair dependence of hydrogen uptake and hydrides stability versus the x (V) content, moreover conversely different due to the presence of the Zr-Ni additive.

Repair of isolated iliac aneurysm with stent-graft implantation and internal iliac coverage may induce significant type II endoleak from patent internal iliac refilling leading to ongoing aneurysm growth. Subsequent treatment of such complication can be challenging especially in case of bilateral iliac involvement. Open repair is technically demanding and often a high risk procedure, while embolization via transfemoral approach is unviable due to the stent-graft coverage precluding direct antegrade access between the common and the internal iliac lumen. Percutaneous retrograde embolization from superior gluteal artery is a feasible technique in case of impossible access through the origin of internal iliac artery.

Age is a main risk factor for stroke and perioperative risk. This study aims to analyze the effect of age by symptomatic status in young patients receiving carotid revascularization.

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Almost one fourth of all the AIDS cases identified in the US are in New York State, which has the largest number of AIDS cases in the nation. The NY State Department of Health predicts that 77,562 cases will have been recorded in the state by 1995, with 61,426 deaths. The case statistics may include 15,000 women and over 3,000 children. In response to this epidemic of staggering proportions, New York State established the AIDS Institute in 1983. This agency initially awarded research grants and contracted with regional service groups to help people infected with human immunodeficiency virus (HIV), the virus associated with AIDS; now, its focus has broadened to include preventive education, HIV counseling and testing, patient care, support of services based in communities, and other activities. Medical care for HIV-infected people and those with AIDS has become increasingly oriented toward outpatient, rather than inpatient, treatment. The Designated AIDS Center program, started in January 1986, allows hospitals to assume responsibility for all aspects of the health care needs of HIV/AIDS patients under a special reimbursement system. AIDS Centers also serve HIV-positive children, adolescents, and pregnant women. By late 1990, 21 hospitals in New York State (13 in New York City) had been designated as AIDS Centers. An important part of the AIDS Centers concept is quality assurance surveillance and utilization reviews: these are carried out by the AIDS Intervention Management System (AIMS), a subunit of which is the HIV Care Criteria Management Program. The Criteria Committee for the Care of HIV-Infected Children, made up of experts throughout the state, has established standards for the care of infected children and adolescents. These standards are presented in a series of articles in the Supplement to the July 1991 issue of The Journal of Pediatrics. (Consumer Summary produced by Reliance Medical Information, Inc.)

Several letters to the editor are presented in response to articles in previous issue including one related to riding experience of a rider with his brother in Florida, other on increase federal gas tax by Jeff Hennie and an article "Snippets" by Don Gomo.

La encefalitis límbica puede presentarse con síntomas psiquiátricos, reversibles con el tratamiento.

Nous montrons qu'il est possible d'obtenir à 1 050 °C, sans surchauffe préalable, un liquide permettant la solidification directionnelle, tout comme dans le procédé nécessitant de hautes températures pour éliminer les germes de cristallisation de YBa2Cu3O7dispersés dans le liquide. Une montée en température rapide d'un mélange de Y2BaCuO5, de BaCuO2et de CuO en proposition stoechiométrique 1-2-3 permet de former un liquide hors équilibre à partir de 880 °C, grâce à de fortes variations de composition locale au sein du mélange réactif, et permet d'atteindre ainsi 1 050 °C, le liquide ayant les propriétés du liquide surchauffé. On montre qu'il est possible de maîtriser une texturation radiale d'un cylindre à partir d'une combinaison de gradients de température de symétrie cylindrique et axiale. Les grains prélevés ont un comportement de monocristaux avec des densités de courants critiques voisines de celles observées dans les autres méthodes.

La texturation de composés YBa2Cu3O7-xa été réalisée par un dispositif de fusion de zone sous champ magnétique. Un fort gradient thermique vertical, suivant lequel les échantillons sont translatés, combiné à un champ magnétique horizontal de 5 teslas permet l'alignement des cristallites avec les plans (a,b) perpendiculaires au champ et parallèles au gradient thermique du four. En champ propre et à 77 K, un courant continu de 1 000 A a circulé à travers un échantillon multigrain de 13 mm2de section et de 20 mm de longueur, prouvant la qualité des joints de grains. Des courants de 200 A ont également circulé dans H = 8 T (H ⊥I ) pour une large fenêtre d'angles entre le champ et les plans (a, b). Ces premiers résultats sont encourageants pour des applications pratiques possibles avec des barreaux texturés de grandes dimensions.

An inhomogeneous magnetic field exerts a force on magnetic materials and can be used either to compensate gravity, control convection in a magnetic liquid or modify the microstructure of a solidified multiphased system where the phases exhibit dilferent magnetic susceptibilities. A homogeneous field may produce a preferred crystallographic alignment in systems which exhibit an anisotropy of their magnetic susceptibility near their melting point. We present an experimental study of those ef[ ects, demonstrating t heir impact on the elaboration of a wide range of materials.

Purpose To evaluate the late results of endovascular aneurysm repair (EVAR) with the endografts currently in use and compare outcomes to older devices.Methods Clinical, demographic, and imaging data on consecutive patients undergoing elective EVAR from January 1997 to December 2011 at a single center were retrieved from an electronic database and reviewed. Newer stent-grafts (NSG) were defined as those introduced after 2004 (second-generation Excluder and Anaconda) or currently in use without modifications (Zenith, Endurant). Of the 1412 consecutive patients (1290 men; mean age 73 years) who underwent elective EVAR in a tertiary university hospital, 882 were treated with NSGs and 530 with older stent-grafts (OSGs).Results In the NSG group, the abdominal aortic aneurysms (AAA) were larger (55.7 vs. 53.2 mm, p<0.0001) and the patients were older (p<0.0001) and less frequently smokers or had pulmonary disease, while hypertension and diabetes were more frequent (all p<0.0001). Thirty-day mortality was 0.8% in the NSG group vs. 1.1% in the OSG group (p=NS). Follow-up ranged from 1 to 174 months (mean 54.1±42.4); the OSG patients had longer mean follow-up compared to the NSG group (80.2±47.9 vs. 38.4±29.1 months, p<0.0001). All-cause survival rates were comparable in both groups. Freedom from late conversion (96.1% vs. 89.1% at 7 years, p<0.0001) or reintervention (83.6% vs. 74.2% at 7 years, p=0.015) and freedom from AAA diameter growth >5 mm (p=0.022) were higher in the NSG group. In adjusted analyses, the use of a new-generation device was a negative independent predictor of reintervention [hazard ratio (HR) 0.67, 95% confidence interval (CI) 0.49 to 0.93, p=0.015] and aneurysm growth (HR 0.63, 95% CI 0.45 to 0.89, p=0.010).Conclusion Newer-generation endografts can perform substantially better than the older devices. In the long term, incidences of reintervention, conversion, and AAA growth are decreased in patients treated with devices currently in use. However, the need for continuous surveillance is still imperative for all endografts.

Specific guidelines for management of cerebrovascular risk in women are currently lacking. This study aims to provide a consensus expert opinion to help make clinical decisions in women with carotid stenosis.

Paradoxical pulmonary embolisms are uncommon emergencies and can occur as a consequence of an aortocaval fistula due to unrecognized dislodgement of thrombus from aortic sac into pulmonary circulation. This study reviewed current literature and therapeutic options in this emergency condition requiring prompt management and repair.

Purpose Endovascular procedures have been increasingly used for salvage of failing vascular access with conflicting results. The aim of this study was to assess the mid-term patency and complication rates of angioplasty procedures performed in a single center for treatment of stenosis compromising vascular accesses.Methods A prospective database of vascular accesses performed in 2006–2010 was investigated. The endovascular approach was applied following a standardized protocol by a dedicated team. A total of 531 consecutive procedures were reviewed (326 men; mean age 70.94 years). Patency rates were estimated using the Kaplan-Meier method.Results There were 199 procedures for failing access: 135 were surgical and 64 angioplasties performed for anastomosis (n=27), venous (n=45) or arterial (n=7) stenosis. Immediate technical success of endovascular procedures was 95.3%(61/64); complication rate was 6.3% (4/64). Primary patency rates were 55% at six months, 49% at 12 months, and 21% at 24 months. In the concurrent group of 135 open procedures, primary patency rates were 80% at six months and 67% at 12 months (P=.002); nevertheless, at 24 months, patency was as low as 49%. Cost estimates for angioplasty revealed additional fees ranging from 411.34 to 446.34 Euro with respect to open surgical procedures.Conclusions Most dysfunctional vascular accesses can be successfully and safely treated by the endovascular route. In spite of poor mid-term durability, the angioplasty balloon might be considered as a bridge, effective, and repeatable solution with reasonable costs to prolong access survival avoiding additional surgery. The failure rate in the mid-term for dysfunctional vascular access may also be high after surgical reintervention.

This review article presents a summary of recent efforts to understand brain temperature and its regulation under different conditions. Brain temperature has a crucial influence on brain processes. Its regulation is the outcome of the balance of core and arterial blood temperatures, cerebral blood flow, brain metabolism, functional conditions, and external temperature. However, the relationship between these factors is not fully understood and several uncertainties remain. There are no satisfactory normative data on temperatures throughout the brain, but new technologies promise to fill this gap. Brain temperature changes with brain functional activation and under pathological conditions in ways that are not understood. A full understanding of brain temperature control is mandatory to optimize attempts at brain cooling during clinical conditions such as stroke and head injury.

The maintenance of a stable temperature is of the utmost importance for the proper functioning of the brain. Brain temperature is tightly linked to mitochondrial energetics. Although Parkinson’s disease is characterized by mitochondrial dysfunction, no data are available on brain temperature. We measured the temperature in the visual cortex and in the centrum semiovale at rest by proton magnetic resonance spectroscopy in patients with Parkinson’s disease and in age-matched and sex-matched control participants. We report evidence of increased temperature in the visual cortex and, to a minor extent, in the centrum semiovale of patients with Parkinson’s disease. The increase in brain temperature is best explained by an energy loss along the oxidative phosphorylationrespiratory chain.

Perturbed Angular Correlation (PAC) measurements were performed at room temperature on samples of Hf7Ni10 and of Hf7Ni10 combined with TiV0.8Cr1.2, and at temperatures in the range from 17 K to 350 K in a concentrated hydride of the combined alloy. The PAC results show that the Hf7Ni10 intergranular phase becomes amorphous in the combination process. The results for the hydride composite show in the Hf7Ni10 phase the formation of a stable interstitial hydrogen state below 100 K and a smooth rearrangement of the hydrogen atoms position above 100 K,corresponding to a slow diffusion movemnet of a short-range nature. A second phase transition is observed at around 300 K, presumably to aphase precursor of the hydrogen desorption of the hydride.

Occurrence of phase transitions in TixVyCrz-H systems was analyzed versus temperature. Hydrogen evacuates from the hydrogenated compounds via two main steps. The 1st step corresponds to the destabilization of the fcc hydrogenated lattice leading to a fcc → bcc martensitic type transformation. The 2nd step occurs according to the decomposition of the resulting hydride via evacuation of hydrogen from the bcc lattice. Both the kinetics and temperature of 1st and 2nd step transformations depend on the composition of the starting TixVyCrz alloys.

Unmanned aerial systems (UAS) have great potential as a platform for acquiring very high resolution aerial imagery for vegetation mapping. However, image processing and classification techniques require adaptation to images obtained with low-cost digital cameras. We developed and evaluated an image processing workflow that included the integration of resolution-appropriate field sampling, feature selection, and object-based image analysis for the purpose of classifying rangeland vegetation from a five-centimeter-resolution UAS image mosaic. Classification tree analysis was used to determine the optimal spectral, spatial, and contextual features. Segmentation and classification rule sets were developed on a test plot and were applied to the remaining study area, resulting in an overall classification accuracy of 78% at the species level and 81% at the structure-group level. The image processing approach provides a roadmap for deriving quality vegetation classification products from UAS imagery with very high spatial, but low spectral resolution.

Hemodynamic principles suggest that primary venous insufficiency follows the hydrostatic column of venous pressure of the limbs, and therefore, venous reflux begins at the lower points and rises upwards. To test the hypothesis of an “ascending development” of reflux, we carried an observational study to analyze the natural evolution of lower limb venous insufficiency.

Purpose: To evaluate the role of aortic stent-graft implantation in managing aortobronchial fistula (ABF).Methods: A search of the Medline, EMBASE, and Cochrane databases for studies reporting on ABF treated with stent-grafts from 1996 to 2008 retrieved 44 articles with data on 82 ABFs. Most (57 ABFs) were published in 30 case reports; the others were retrieved from 14 acute aortic series.Results: In the perioperative period, 4 (4.9%) deaths (3 from hemorrhage) were reported, but no paraplegia/stroke. Local graft-related complications were more common, including arm ischemia (n=4) and iliac ruptures (n=3). Long-term data were available for only a few studies. Recurrent hemorrhage (14%) occurred from 2 weeks to 9 years after repair. Reinterventions to manage recurrences were generally based on redo endografting.Conclusion: A contaminated field and the emergency setting make stent-graft repair of ABFs challenging. After successful stent-graft deployment, the risks of recurrence and mortality are concerning. One can infer from the data that endografting might be a reasonable temporary bridge solution, but potentially unstable in the long term. Open repair likely will remain indicated once the patient has been stabilized physiologically with emergent stent-graft repair.

Distributed wireless systems present many security issues, and offering security preserving network resources is often a challenging effort. Offering security through only cryptography is not always a suitable solution if the high dynamic context of MANET is considered and the trust mechanism that reduces the computationally intensive number of security operations becomes strategic. In this work, a well-known routing protocol, called SAODV, has been considered. To improve its performance and offer more resilience to attack from malicious nodes authenticated by the network, some additional features are added. A preventive approach based on a cryptographic mechanism and a reactive approach to detect anomalous and malicious nodes are considered. An extension of SAODV offering an Intrusion Detection Mechanism (IDM) and a Trust-based Mechanism (TBM) to promote the collaboration of the cooperating nodes and penalize the selfish nodes are proposed. Simulation results were performed under a NS-2 simulator to show the effectiveness of our proposal compared with AODV and SAODV. Simulation parameters, such as Normalized Routing Overhead, Data Packet Delivery Ratio, average number of signatures and throughput of collaborating and malicious nodes, have been considered.

The axonal forms of Charcot-Marie-Tooth (CMT2) disease are a clinically and genetically heterogeneous group of disorders. Mitofusin 2 gene (MFN2) mutations are the most common cause of CMT2. Complex phenotypes have been described in association with MFN2gene mutations, including CMT2 with pyramidal features (hereditary motor and sensory neuropathy HSMN V) and CMT2 with optic atrophy (HMSN VI).

Change in cognition is being increasingly recognized as an important outcome measure; however, the role of carotid revascularization on this issue remains to be determined. It is still under debate whether carotid artery stenting and carotid endarterectomy have the same influence on neuropsychological functions.

In this paper the performance of an Integrated Services (IntServ) Satellite network, loaded with two QoS traffic classes, Controlled Load Services (CLS) and Guaranteed Services (GS), has been shown. The GS Burst Loss Percentage (BLP) has been examined and the behavior of the system loaded with both classes of service has been analyzed. A novel management of CLS has been considered in order to analyze the system behavior with different percentages of GS and CLS traffic in terms of burst loss. We have studied the Call Admission Control (CAC) phase for CLS in the satellite network. Different simulations have been performed varying some network parameters and we have analyzed the CLS bandwidth levels declared in satellite admission phase. Furthermore, a regression analysis on simulation results is carried out in order to obtain an expression for the average GS BLP as a function of the traffic load and CLS peak values.