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A generic model for MIMO wireless propagation channels in macro- and microcells

This paper derives a generic model for the multiple-input multiple-output (MIMO) wireless channel. The model incorporates important effects, including i) interdependency of directions-of-arrival and directions-of-departure, ii) large delay and angle dispersion by propagation via far clusters, and iii) rank reduction of the transfer function matrix. We propose a geometry-based model that includes t

Interactions between Sulfide Minerals and Alkylxanthate Ions .2. A Vibration Spectroscopic and Atomic-Absorption Spectrophotometric Study of the Interactions between Sphalerite and Copper-Activated Sphalerite, and Ethyl-Decylxanthate and N-Decylxanthate Ions in Aqueous and Acetone Solutions

The reactions between three sphalerite samples and ethyl- and n-decylxanthate ions have been studied in aqueous and acetone solutions. Qualitative analysis of the species present on the sphalerite surfaces before and after treatment with these ions have been performed by means of diffuse reflectance infrared Fourier transform spectroscopy. Atomic absorption spectrophotometry has been used to deter

L22 ribosomal protein and effect of its mutation on ribosome resistance to erythromycin

The ribosomal protein L22 is a core protein of the large ribosomal subunit interacting with all domains of the 23 S rRNA. The triplet Met82-Lys83-Arg84 deletion in L22 from Escherichia coli renders cells resistant to erythromycin which is known as an inhibitor of the nascent peptide chain elongation. The crystal structure of the Thermus thermophilus L22 mutant with equivalent triplet Leu82-Lys83-A

More on the 1/f2 Phase Noise Performance of CMOS Differential-Pair LC-Tank Oscillators

This paper presents a rigorous phase noise analysis in the 1/f2 region for the differential CMOS LC-tank oscillator with both nMOS and pMOS switch pairs. A compact, closed-form phase noise equation is obtained, accounting for the noise contributions from both tank losses and transistors currents, which allows a robust comparison between LC oscillators built with either one or two switch pairs. The

Physical characteristics of young men with cleft lip, with or without cleft palate, and cleft palate only.

We report the weight, stature, body mass index (BMI), and muscular strength of men about 19 years old who have cleft lip, either with or without cleft palate (CLP), or cleft palate only (CP). Data were obtained from the Swedish National Service enrolment register for the years 1991 - 97, and concerned 335 men with CLP and 88 with CP, who were compared with a control group of 272 879 men. The data

The relation between accidents and output in Swedish industry

Traditionally, occupational injury rates are measured as number of injuries per amount of work. In contrast, we propose that for certain purposes of economic policy, a more relevant measure could be obtained by considering them as production costs and comparing them with output. This was accomplished by replacing “hours worked” in the traditional formulae for estimating accident risk with “value a

Prostate specific antigen based biennial screening is sufficient to detect almost all prostate cancers while still curable

PURPOSE: We evaluated whether biennial screening with prostate specific antigen (PSA) only is sufficient to detect prostate cancer while still curable. MATERIALS AND METHODS: In Goteborg, Sweden 9,972 men 50 to 65 years old were randomized to PSA screening. During 1995 and 1996 these men were invited for a first PSA screening and invited during 1997 and 1998 for a second screening. The screening p

How do Swedish paediatric clinics diagnose coeliac disease? Results of a nationwide questionnaire study

Background and aim: Diagnosis of coeliac disease is based on the demonstration of enteropathy in a small bowel biopsy. Correct diagnosis is of utmost importance, since the need for dietary management is life long, and inadequate treatment may lead to potentially serious complications. The Swedish Working Group for Paediatric Coeliac Disease has published guidelines for the diagnosis of childhood c

The role of vascular surgery in chronic leg ulcers: report from a specialized ulcer clinic.

Experience gained from cooperation between dermatologists and vascular surgeons in 177 patients evaluated at a joint leg ulcer clinic is reported. Patients were divided into two subgroups: (i) 86 patients with healed ulcers and (ii) 91 patients with ongoing therapy-resistant ulcers. Venous insufficiency was the most common etiology in both subgroups (87% and 55%, respectively). Of previous therapy

Morphogenesis in the nematode-trapping fungus Arthrobotrys oligospora - an extensive plasticity of infection structures

st nematode-trapping fungi are dependent on specific hyphal structures on or in which nematodes can be trapped mechanically or by adhesion. These structures are a prerequisite for the ability of the fungus to invade a host and are thus crucial for survival as well as virulence. The diversity of trapping structures is large and highly dependent on the environment of the fungus. Within one single sp

Photon events with missing energy in e(+)e(-) collisions at root s=130 to 209 GeV

The production of single- and multi-photon events has been studied in the reaction e(+) e(-) --> gamma(gamma) + invisible particles. The data collected with the DELPHI detector during the years 1999 and 2000 at centre-of-mass energies between 191 GeV and 209 GeV was combined with earlier data to search for phenomena beyond the Standard Model. The measured number of light neutrino families was cons

Blunt renal trauma. Analysis of 417 patients

Case records of 417 patients, from a well-defined area, who were hospitalized because of blunt renal trauma during the period 1950-1979 were analyzed. The incidence increased during the final decade, corresponding to a rising incidence of motor traffic accidents and sports injuries. Young patients, between 10 and 29 years of age, were responsible for the increase and half of all patients were in t