ATM-based transport architecture for multiservices wirelesspersonal communication networks

This paper presents an ATM-based transport architecture for next-generation multiservices personal communication networks (PCN). Such “multimedia capable” integrated services wireless networks are motivated by an anticipated demand for wireless extensions to future broadband networks. An ATM compatible wireless network concept capable of supporting a mix of broadband ISDN services including constant bit-rate (CBR), variable bit-rate (VBR), and packet data transport is explored from an architectural viewpoint. The proposed system uses a hierarchical ATM switching network for interconnection of PCN microcells, each of which is serviced by high-speed, shared-access radio links based on ATM-compatible cell, relay principles. Design issues related to the physical (modulation), media access control (MAC), and data-link layers of the ATM-based radio link are discussed, and preliminary technical approaches are identified in each case. An example multiservice dynamic reservation (MDR) TDMA media access protocol is then considered in further detail, and simulation results are presented for an example voice/data scenario with a proportion of time-critical (i.e., multimedia) packet data. Time-of-expiry (TOE) based queue service disciplines are also investigated as a mechanism for improving the quality-of-service (QoS) in this scenario     

Cognitive treatments for eating disorders.

Cognitive-behavioral therapy (CBT) is applicable to all eating disorders but has been most intensively studied in the treatment of bulimia nervosa (BN). CBT is designed to alter abnormal attitudes about body shape and weight, replace dysfunctional dieting with normal eating habits, and develop coping skills for resisting binge eating and purging. CBT is effective in reducing all core features of BN and shows good maintenance of therapeutic improvement. Although superior to therapy with antidepressant drugs, CBT has not been shown to be consistently superior to alternative psychological treatments. Different hypotheses about CBT's mechanisms of action are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Energy dissipation via radiative recombination and vibronic relaxation in σ-delocalized silicon backbone network polymers

The nature of ultrafast energy dissipation in poly(n-hexylsilyne), a prototypical σ-delocalized alkysilicon network polymer, is explored. This disordered silicon backbone material exhibits strong near-UV to visible band-edge absorption and a high quantum yield of visible emission. The time evolution of the emission band is studied over four decades of time using time-resolved luminescence as a probe. The data indicate that while there is an ‘intrinsic’ Stokes shift after photoexcitation due to kinetic energy relaxation (<10ps), thermalization within a dense band of vibronic states via intramolecular phonon-assisted hopping on a nanosecond timescale is the dominant mechanism for excited-state decay. The data can be understood in terms of theoretical predictions for energy relaxation in disordered materials.     

Survey of animal livers for vitamin A content.

Retail samples of livers from calf (23), ox (18), lamb (17), pig (15), chicken (16) and turkey (1) were analysed to determine levels of vitamin A (all trans-retinol) and to aid assessment of the effects of using vitamin supplemented compound feedingstuffs for livestock. For comparison, 22 liver samples from lambs reared on diets not containing vitamin-supplemented compound feedingstuffs and four samples of liver from ox which had received supplemented feed but not during the last four months prior to slaughter were also analysed. The chosen method of analysis utilized saponification, solvent extraction and normal-phase high performance liquid chromatography with fluorescence detection. For all species analysed, the levels of vitamin A ranged from 10 to 1100 mg/kg, with all but seven at or below 400 mg/kg. For lamb and ox livers, the mean levels were 310 mg/kg and 200 mg/kg respectively for retail samples. The mean levels were 220 mg/kg (lamb) and 120 mg/kg (ox) in liver samples from animals fed controlled diets. The results are of the same order as those reported over recent years.     

The role of dopamine in the mechanism of the regulation of the digestive-transport functions of the enterocyte membrane during stress

The L-DOPA and sulpiridinum effects on the enzymatic transporting function of the enterocytes' membrane, were studied in rats under stress. The L-DOPA was shown to hinder the absorption rate of glucose, whereas sulpiridinum was shown to suppress the main enzymes excepting snerase and alkaline phosphatase, to increase the monomeric and hydrolysate glucose transport. The L-DOPA seems to play a modifying role in the regulation and integration of the digestive-transporting function of the enterocytes' membrane in rats under stress.     

Microbiological results from milk samples obtained premilking and postmilking for the diagnosis of bovine intramammary infections.

Bacteriological culture results were compared between 336 pairs of quarter milk samples collected premilking and postmilking. Using a positive result on either premilking or postmilking samples as the definitive diagnosis, premilking sampling sensitivity was 91% for Staphylococcus aureus, 91% for coagulase-negative staphylococci, and 97% for Streptococcus other than agalactiae. Postmilking sampling sensitivities were 81, 45, and 58%, respectively, for the same pathogens. Requiring both premilking and postmilking samples for the definitive diagnosis, specificities were 92, 86, and 95% for premilking sampling alone and 96, 98, and 99% for postmilking sampling alone. Such differences in specificity would result in major differences in predictive value of a positive culture for herds with a low prevalence. Multiple isolates were significantly more common from premilking samples.     

Spectral predictions for pulse interval and width modulation

An expression for the frequency spectrum of pulse interval and width modulation (PIWM) is presented. Experimental results obtained have shown close agreement with spectral predictions from the formula. Performance figures are also included from a practical PIWM optical-fibre transmission system intended for use with TV and video signals.<>