Scattering of the UHECR at small pitch angle by damped plasma waves

In spite a lot of theoretical and experimental effort that has been achieved in ultra-high energy cosmic ray (UHECR) scattering research in last few decades, some questions remain unanswered, or partially answered. Two of them, that will be in the focus of this paper are: possible source of UHECRs and the acceleration mechanism of cosmic rays beyond PeV energies. Small pitch-angle scattering of UHECRs and possible confinement has been investigated using quasilinear theory in order to analytically calculate pitch-angle Fokker-Planck coefficient. CR particles resonantly interact with oblique low frequency damped waves. We show that the resonance function is broadened due to damping effects and this result is compared with the nonlinear broadening. Unlike the case of purely parallel (or antiparallel) propagating waves in slab turbulence, the presence of the compressive magnetic field component of oblique fast-mode waves allows the cosmic ray particles to resonantly interact with these waves through the n = 0 resonance, together with gyroresonance, which strongly influence the Hillas limit. The derived results can be used to compute the parallel mean free path for all forms of the turbulence spectrum; it has been applied on the transport and propagation of CRs close to ultra-high energies in the Galaxy. An accurate understanding of particle acceleration in astrophysical sources could help to interpret eventual transition from Galactic to extragalactic origin of cosmic rays, if any, and the shape of the UHECR spectrum at the highest energies

Army Information Technology Procurement: a Business Process Analysis

This thesis presents a business process analysis of the Army\u27s ICT procurement system. The research identified several inefficiencies and proposes several potential solutions. the contributions of this research include a unified taxonomy, a method to prioritize requests, and system architecture products for development of an automated and sustainable collaboration interface for the CIO/G6 to streamline their IT acquisition process. Development of a centralized system would reduce waste in the request process from submission to formal accounting, hasten the movement of requests between stakeholders, maintain a digital signature authorization for each approval authority, provide a reporting database to recognize reprogramming thresholds, and deliver relevant metrics and analysis to help inform the Army\u27s IT resourcing decisions

Bilateral anatomic variation in the relation of the upper trunk of the brachial plexus to the anterior scalene muscle

The brachial plexus represents a field of many anatomical variations with impor- tant clinical implications, especially in the diagnosis and treatment of the thoracic outlet syndrome (TOS). The case described in this paper presented a novel bilateral variation in the relation of the upper trunk of the brachial plexus to the anterior scalene muscle. The ventral rami of the C5 and C6 spinal nerves perforated the anterior scalene muscle simultaneously through a common opening, and joined to form the upper trunk. Previous literature reports described variations of the brachial plexus and the scalene muscles, as well as the embryological basis for their presence. The case reported herein helps to improve the comprehension of the TOS, as well as the diagnostic and therapeutical approach to this syndrome

Morphometric characteristics of the optic canal and the optic nerve

Background: The optic nerve (ON), a major component of the visual system, is divided into four segments: the intrabulbar (IB), the intraorbital (IO), the intraca- nalicular (ICn) and the intracranial (ICr). The ICr ends with the two nerves partially decussating in the optic chiasm (OCh). The purpose of this study is to provide a detailed description of the dimensions of the OC (the diameter and the surface area of its foramina and the central segment, as well as the length of the OC and the thickness of its walls) as well as the ON (the length of the ON segments, the diameter of the ICn segment of the ON, the angle of decussation in the OCh, as well as the distance between the two ON at the cranial foramen of the OC).  Materials and methods: The acquired data was then used to estimate the volu- me of the OC and the ICn segment of the ON. The morphometric research was performed on 25 cadavers (17 male and 8 female) and 30 skulls.  Results: The surface area of the central segment of the OC was significantly smaller than the cranial foramen (p = 0.02) and the orbital foramen (p = 0.009). The inferior wall of the OC was significantly shorter than the other OC walls (p < 0.0001). The IO segment of the ON was the longest, where the difference to the ICn and ICr was statistically significant (p < 0.0001). The surface area of the ON at the cranial foramen was significantly larger than the surface area at the central segment of the OC (p = 0.02) and orbital foramen (p < 0.0001). The difference between the surface areas of the ON at the orbital foramen and the central segment of the OC was also statistically significant (p = 0.01). The estimated volume of the OC was calculated to be 190.72 mm3, and the volume of the ICn segment of the ON was estimated to be 50.25 mm3.  Conclusions: It is absolutely crucial to open the central segment of the OC when decompressing the ON, due to the narrowing of the OC in this segment.

A multilevel control system for the large space telescope

A multilevel scheme was proposed for control of Large Space Telescope (LST) modeled by a three-axis-six-order nonlinear equation. Local controllers were used on the subsystem level to stabilize motions corresponding to the three axes. Global controllers were applied to reduce (and sometimes nullify) the interactions among the subsystems. A multilevel optimization method was developed whereby local quadratic optimizations were performed on the subsystem level, and global control was again used to reduce (nullify) the effect of interactions. The multilevel stabilization and optimization methods are presented as general tools for design and then used in the design of the LST Control System. The methods are entirely computerized, so that they can accommodate higher order LST models with both conceptual and numerical advantages over standard straightforward design techniques

Red mud-blast furnace slag-based alkali-activated materials

The aluminum Bayer production process is widespread all over the world. One of the waste products of the Bayer process is a basic aluminosilicate bauxite residue called red mud. The aluminosilicate nature of red mud makes it suitable as a precursor for alkali-activated materials. In this work, red mud was mixed with different percentages of blast furnace slag and then activated by sodium silicate solution at different SiO2/Na2O ratios. Obtained samples were characterized by chemical–physical analyses and compressive strength determination. Very high values of compressive strength, up to 50 MPa, even for high percentage of red mud in the raw mixture (70 wt.% of RM in powder mixture), were obtained. In particular, the higher compressive strength was measured for cubic samples containing 50 wt.% of RM, which showed a value above 70 MPa. The obtained mixtures were characterized by no or scarce environmental impact and could be used in the construction industry as an alternative to cementitious and ceramic materials

Alkali-Activated Red Mud and Construction and Demolition Waste-Based Components: Characterization and Environmental Assessment

The aluminum Bayer production process is the most diffused process in the world, but it creates a high amount of basic waste material known as red mud (RM). The use of RM as a precursor of alkali-activated materials is one of the best opportunities for both the ecosystem and the economy. In the present work, mortar samples were obtained by alkali activation of RM with various percentages of blast-furnace slag (BFS) and inert construction and demolition sands. This process creates samples that have a low environmental impact and that can be used as an alternative in the construction industry to cement materials or ceramic ones. The development of these new materials could also represent a way to reduce the CO2 emissions linked to cement and ceramic brick production. In the present study, cubic 40 mm samples reported very interesting values in compressive strength, with a maximum of about 70 MPa for low environmental impact mortars. With such a material, it is possible to create solid bricks for structural use and concrete tiles for road paving or use it for other purposes. Mortar specimens were prepared and characterized, and an LCA analysis with a “cradle-to-gate” approach was carried out for a comparison of the environmental impact of the studied mortars with other materials currently marketed

Characterisation of surface oxygen groups on different carbon materials by the Boehm method and temperature-programmed desorption

The surface characteristics of different carbon materials: activated carbon, carbon felt, glassy carbon and a porous carbon monolith were investigated. The specific surface area was examined by the BET method with N(2) adsorption, the amount and the type of surface oxygen groups by Boehm titration as well as by temperature-programmed desorption (TPD). By comparing the results obtained using BET analysis with those of TPD and the Boehm method, it was found that the number of surface groups was not proportional to the specific surface area. The total amount of oxygen groups, obtained by TPD, is higher than the amount obtained by Boehms method for porous samples. The inconsistencies between these results originate from the fact that the Boehm method is limited to the determination of acidic and basic groups, whereas TPD provides information on the total number of all surface oxygen groups. In addition, the presence of porosity could reduce the solvent-accessible surface in the Boehm method. The TPD profiles of CO evolution showed the presence of a low temperature maximum, below 650 K, which originates from CO(2) reduction on the carbon material surface

Percutaneous Ventricular Restoration (PVR) Therapy Using the Parachute Device in 100 Subjects with Ischaemic Dilated Heart Failure: One-Year Primary Endpoint Results of PARACHUTE III, a European Trial

AIMS: This prospective, non-randomised, observational study conducted in Europe was designed in order to assess the long-term safety and efficacy of the Parachute device in ischaemic heart failure subjects as a result of left ventricle remodelling after anterior wall myocardial infarction. METHODS AND RESULTS: One hundred subjects with New York Heart Association Class II-IV ischaemic heart failure (HF), ejection fraction (EF) between 15% and 40%, and dilated akinetic or dyskinetic anterior-apical wall without the need to be revascularised were enrolled. The primary safety endpoint was procedural- or device-related major adverse cardiac cerebral events (MACCE). The secondary safety endpoint was the composite of mortality and morbidity. Secondary efficacy endpoints included haemodynamic measurements determined by echocardiography, LV volume indices, and assessment of functional improvement measured by a standardised six-minute walk test. Of the 100 subjects enrolled, device implantation was successful in 97 (97%) subjects. The one-year rates of the primary and secondary safety endpoints were 7% and 32.3%, respectively. The secondary endpoints, LV volume reduction (p<0.0001) and six-minute walk distance improvement (p<0.01), were achieved. CONCLUSIONS: The favourable outcomes observed in this high-risk population provide reassuring safety and efficacy data to support adoption of this technology as a therapeutic option for HF subjects.info:eu-repo/semantics/publishedVersio