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BACKGROUND Previous literature demonstrates increased mortality for traumatic brain injury (TBI) with transfer to a Level II versus Level I trauma center. Our objective was to determine the effect of the most recent American College of Surgeons-Committee on Trauma (ACS-COT) "Resources for the Optimal Care of the Injured Patient" resources manual ("The Orange Book") on outcomes after severe TBI after interfacility transfer to Level I versus Level II center. METHODS Utilizing the Trauma Quality Program Participant Use File of the American College of Surgeons admission year 2017, we identified patients with isolated TBI undergoing interfacility transfer to either Level I or Level II trauma center. Logistic regression was performed to determine independent associations with mortality. RESULTS There were 10,268 (71.6%) transferred to a Level I center and 4,025 (28.4%) were transferred to a Level II center. They were mostly male (61.4%) with a mean ± SD age of 61 ± 20.8 years. Mean Injury Severity Score was 16.3 ± 6.3 and most were injured in a single-level fall (51.5%). Patients transferred to a Level I center were less likely to be White (82.3% vs. 84.7%, 0.002) and more likely to have sustained penetrating trauma (2.7% vs. 1.6%

This paper addresses Co-Channel Interference (CCI) problem in cellular networks. Therefore, network performance improvements through reducing CCI are evaluated using different four interference mitigation techniques. These techniques represent traditional sectored Fractional Frequency Reuse (FFR), sectored FFR do Beamforming (BF), Relay Assisted (R-A) sectored FFR and R-A sectored FFR do BF technique. Additionally, each one of the techniques which cooperative BF covers the horizontal, vertical and Three Dimensional (3D) BF techniques. Consequently, sectored FFR do BF contains three different scenarios. These scenarios indicate sectored FFR do horizontal BF, sectored FFR do vertical BF and sectored FFR do 3D BF. Furthermore, there are three different configurations of applying BF in R-A sectored FFR do BF. These configurations signify Relay Station (RS) do BF only, Base Station (BS) do BF only and both RS and BS do BF. Therefore, each configuration consists of three different scenarios according to the applied BF technique. Consequently, nine different scenarios are studied. A comparison of all scenarios in different techniques is introduced to enhance the network Quality of Service (QoS). Analytical treatments are conducted. As a result, closed-form expressions for worst-cases Cell Edge User's (CEU's) Signal to Interference Ratio (SIR), Cell Centre User's (CCU's) SIR and inner radius are implemented. These expressions are used to compare different techniques using various performance evaluation metrics. The results show, that as unpredicted, the performance of R-A sectored FFR is close to that of R-A sectored FFR BF in low SIR threshold and high PL exponent ranges. Therefore, R-A sectored FFR is preferred in use from the network cost and power consumption perspectives. Furthermore, vertical BF shows performance close to 3D BF in low Path-loss (PL) exponent range. Therefore, applying vertical BF is preferable with regard to the network budget and energy preserve. Moreover, it is observed, that configuration of BS do BF is superior to other configurations when horizontal or vertical BF technique is applied. Additionally, the configuration of both RS and BS do BF outperforms the other configurations when 3D BF is applied. However, as unexpected, it performs worse than them when the other BF techniques are applied. The work outcomes attain much higher CEU's SIR improvement. Therefore, the outage probability is decreased. Thus, network can cover more users. Accordingly, the total network cost is reduced. So, this treatment improves the network performance while keeping lower network cost. .

The grafting of methacrylic acid (MAA) and other vinyl monomers onto cotton cellulose in fabric form was investigated in an aqueous medium with a potassium peroxydiphosphate–metal ion–cellulose thiocarbonate redox initiation system. The graft copolymerization reaction was influenced by peroxydiphosphate (PP) concentration, the pH of the reaction medium, monomer concentration, the duration and temperature of polymerization, the nature of vinyl monomers, and the nature and concentration of metallic ions (activators). On the basis of a detailed investigation of these factors, the optimal conditions for the grafting of MAA onto cotton fabric with the said redox system were as follows: [Fe2+] = 0.1 mmol/L, [PP] = 2 mmol/L, [MAA] = 4%, pH-2, grafting time = 2 h, grafting temperature = 70°C, and material/liquor ratio = 1 : 50. Under these optimal conditions, the graft yields of different monomers were in the following sequence: MAA ≫ acrylonitrile > acrylic acid > methyl acrylate > methyl methacrylate. The unmodified cellulosic fabric (the control) had no ability to be grafted with MAA with the PP–Fe2+ redox system. The percentage of grafting onto the thiocarbonated cellulosic fabric was more greatly enhanced in the presence of iron salts than in their absence. This held true when the lowest concentrations of these salts were used separately. A suitable mechanism for the grafting processes is suggested, in accordance with the experimental results. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1879–1889, 2003

The feasibility of a cellulose thiocarbonate–azobisisobutyronitrile (AIBN) initiation system to induce graft copolymerization of methyl methacrylate (MMA) and other acrylic monomers onto cotton fabric was investigated. Other acrylic monomers were acrylic acid, acrylonitrile, and methyl acrylate. The initiation system under investigation was highly activated in the presence of a metal-ion reductant or a metal-ion oxidant in the polymerization medium. A number of variables in the grafting reaction were studied, including AIBN concentration, pH of the polymerization medium, nature of substrate, monomer concentration, duration and temperature of polymerization, and composition of the solvent/water polymerization medium. The solvents used were methanol, isopropanol, 1,4-dioxane, cyclohexane, benzene, dimethyl formamide, and dimethyl sulfoxide. There were optimal concentrations of AIBN (5 mmol/L), MMA (8%), Fe2+ (0.1 mmol/L), Mn2+ (8 mmol/L), and Fe3+ (2 mmol/L). A polymerization medium of pH 2 and temperature of 70°C constituted the optimal conditions for grafting. The methanol/water mixture constituted the most favorable reaction medium for grafting MMA onto cotton fabric by using the Fe2+–cellulose thiocarbonate–AIBN redox system. MMA was superior to other monomers for grafting. The unmodified cotton cellulose showed very little tendency to be grafted with MMA compared with the chemically modified cellulosic substrate. A tentative mechanism for the grafting reaction was proposed. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1261–1274, 2004

Two new flavonol glycosides were isolated from dried leaves of Koelreuteria paniculata Laxm. (Sapindaceae) and characterized as 6,8-dihydroxy-afzelin and afzelin 3"-O-gallate, based on chemical and spectral evidences, in addition to nine known polyphenolic metabolites, including eight isolated for the first time from this species.

Casein was enzymatically hydrolyzed for potential use in a hypoallergenic infant formula. Samples from the digest at different hydrolysis time (HT) intervals were tested for antigenicity, hydrophobicity, net charge (zeta potential), and emulsifying activity. Casein antigenicity loss could be approximated by three-phased first-order kinetics. Extensive antigenicity loss occurred during the first 10% of HT and relatively small changes occurred during the remaining 90% of HT. Hydrophobicity and emulsifying activity decreased, while the magnitude of the net charge increased (P

Cette structure hexagonale C 14 peut etre traitee comme un empilement compact hexagonal de couches doubles A et B, formant la sequence AB AB AB...AB AB AB. Toute alteration de cette sequence entraine la formation de defauts de deformation et de twin

Etude de la composition des phases, de la structure et des reorientations de spins dans ces alliages quasi-binaires. Construction d'un diagramme de phases magnetique. Cette etude est effectuee par spectroscopie Mossbauer (resonance-γ) et par diffractometrie de rayons-X des polycristaux dans l'intervalle de temperatures 4,2-300 K