Measurement of the helicity of W bosons in top quark decays.

We use the transverse momentum spectrum of leptons in the decay chain t-->bW with W-->lnu to measure the helicity of the W bosons in the top quark rest frame. Our measurement uses a t&tmacr; sample isolated in 106+/-4 pb(-1) of data collected in p&pmacr; collisions at sqrt[s] = 1.8 TeV with the CDF detector at the Fermilab Tevatron.

Measurement of J/psi and psi(2S) polarization in pp collisions at sqrt[s] = 1.8 TeV.

We have measured the polarization of J/psi and psi(2S) mesons produced in pp collisions at sqrt[s] = 1.8 TeV, using data collected at the Collider Detector at Fermilab during 1992-1995. The polarization of promptly produced J/psi [psi(2S)] mesons is isolated from those produced in B-hadron decay, and measured over the kinematic range 4 [5.

Search for a W' boson via the decay mode W'-->munumu in 1.8 TeV pp collisions.

We report the results of a search for a W' boson produced in pp collisions at a center-of-mass energy of 1.8 TeV using a 107 pb-1 data sample recorded by the Collider Detector at Fermilab. We consider the decay channel W'-->&munumu and search for anomalous production of high transverse mass munumu lepton pairs.

Search for scalar top and scalar bottom quarks in pp collisions at square root s=1.8 TeV.

We have searched for direct pair production of scalar top and scalar bottom quarks in 88 pb-1 of pp collisions at sqrt[s]=1.8 TeV with the CDF detector. We looked for events with a pair of heavy flavor jets and missing energy, consistent with scalar top (bottom) quark decays to a charm (bottom) quark and a neutralino.

Search for scalar top quark production in p&pmacr; collisions at sqrt.

We have searched for direct production of scalar top quarks at the Collider Detector at Fermilab in 88 pb(-1) of p&pmacr; collisions at sqrt[s] = 1.8 TeV. We assume the scalar top quark decays into either a bottom quark and a chargino or a bottom quark, a lepton, and a scalar neutrino.

Diffractive dijets with a leading antiproton in &pmacr;p collisions at sqrt.

We report results from a study of events with a leading antiproton of beam momentum fraction 0.905 View Article and Find Full Text PDF

The impact of risk shifting and contracting on mental health service costs in California.

This paper identifies the impact of "program realignment," a 1991 California state policy that significantly enhanced local governments' financial risk and programmatic authority for public mental health services, on treatment costs per user, and on the mix of inpatient and outpatient service costs. The study employs a natural pre-realignment and post-realignment design using the 59 California local mental health authorities (LMHAs) as the unit of analysis over a seven-year period spanning policy implementation. Total treatment and inpatient cost per user decreases and outpatient cost per user increases after program realignment.

Limits on light gravitino production and new processes with large missing transverse energy in p&pmacr; collisions at sqrt.

Events collected by the Collider Detector at Fermilab (CDF) with an energetic jet plus large missing transverse energy can be used to search for physics beyond the standard model. We see no deviations from the expected backgrounds and set upper limits on the production of new processes. We consider in addition the production of light gravitinos and set a limit at 95% confidence level on the breaking scale sqrt[F]>/=217 GeV, which excludes gravitino masses smaller than 1.

Search for new particles decaying to t&tmacr; in p&pmacr; collisions at radicals = 1.8 TeV.

We use 106 pb (-1) of data collected with the Collider Detector at Fermilab to search for narrow-width, vector particles decaying to a top and an antitop quark. Model independent upper limits on the cross section for narrow, vector resonances decaying to t&tmacr; are presented. At the 95% confidence level, we exclude the existence of a leptophobic Z' boson in a model of top-color-assisted technicolor with mass M(Z')<480 GeV/c(2) for natural width gamma = 0.

Search for second and third generation leptoquarks including production via technicolor interactions in p&pmacr; collisions at radicals = 1.8 TeV.

We report the results of a search for second and third generation leptoquarks using 88 pb(-1) of data recorded by the Collider Detector at Fermilab. Color triplet technipions, which play the role of scalar leptoquarks, are investigated due to their potential production in decays of strongly coupled color octet technirhos. Events with a signature of two heavy flavor jets and missing energy may indicate the decay of a second (third) generation leptoquark to a charm (bottom) quark and a neutrino.

Measurement of b-Quark Fragmentation Fractions in pp[over ¯] Collisions at sqrt[s]=1.8 TeV.

We have studied the production of B hadrons in 1.8-TeV pp[over ¯] collisions. We present measurements of the fragmentation fractions, f_{u}, f_{d}, f_{s}, and f_{baryon}, of produced b quarks that yield B^{+}, B^{0}, B_{s}^{0}, and Λ[over ¯]_{b}^{0} hadrons.

Effects of tylosin on concentrations of Fusobacterium necrophorum and fermentation products in the rumen of cattle fed a high-concentrate diet.

Objective: To determine effects of tylosin on ruminal concentrations of Fusobacterium necrophorum and fermentation products in cattle during rapid adaptation to a high-concentrate diet.

Animals: 6 steers fitted with ruminal cannulas.

Procedure: Steers were assigned randomly to 2 treatment groups and switched from a 0 to an 85% concentrate diet during a 4-day period.

Effect of virginiamycin on ruminal fermentation in cattle during adaptation to a high concentrate diet and during an induced acidosis.

The objective of Exp. 1 was to compare the effects of virginiamycin (VM; 0, 175, or 250 mg x animal(-1) x d(-1)) and monensin/tylosin (MT; 250/ 90 mg x animal(-1) x d(-1)) on ruminal fermentation products and microbial populations in cattle during adaptation to an all-concentrate diet. Four ruminally cannulated, Holstein steers were used in a 4x4 Williams square design with 21-d periods.

Effects of contracting and local markets on costs of public mental health services in California.

Objective: This study examined the factors that determine whether mental health services provided under contracts with private providers are more cost-efficient than services provided directly by public mental health agencies.

Methods: Data on service costs for 1993 were obtained from the California Department of Mental Health cost reporting and data collection system and from a survey of local mental health departments. Ordinary least-squares regression was used to estimate the effect of contracting, local market conditions, and contracting procedures on unit costs of seven core mental health services: psychiatric inpatient care, rehabilitative day service, intensive day service, individual therapy, medication management, crisis intervention, and case management.

Biochemical and ribotypic comparison of Actinomyces pyogenes and A pyogenes-like organisms from liver abscesses, ruminal wall, and ruminal contents of cattle.

Objective: To isolate Actinomyces pyogenes and A pyogenes-like (APL) organisms from the ruminal wall and ruminal contents of cattle and compare them with isolates from liver abscesses from the same animals, using ribosomal DNA restriction fragment length polymorphism analysis or ribotyping.

Procedure: Specimens of liver abscesses, ruminal walls, and ruminal contents were collected from 59 cattle at slaughter. All beta-hemolytic, pinpoint colonies that were gram positive, pleomorphic rod-shaped, and catalase negative, and that hydrolyzed casein and gelatin were presumptively identified as A pyogenes and were characterized biochemically, using an identification kit.

International health medical education consortium. Its history, philosophy, and role in medical education and health development.

The International Health Medical Education Consortium (IHMEC) is the first national organization created to link faculty in North American medical schools that teach international health. This article presents IHMEC's role in international medical education, including their mission, structure, and future agendas.

Motor unit behavior in canine motor neuron disease.

Hereditary canine spinal muscular atrophy (HCSMA) is an autosomally dominant disease of motor neurons that shares many pathological features with human motor neuron disease. A particularly striking feature of the affected, accelerated phenotype (homozygous HCSMA) is that profound weakness develops before appreciable motor neuron cell death occurs (Cork et al., 1989a), implying that motor unit functional defects occur initially.

Comparison of four commercially available rapid enzyme immunoassays with cytotoxin assay for detection of Clostridium difficile toxin(s) from stool specimens.

Rapid (2.5- to 3.5-h) enzyme immunoassays (EIAs) for the detection of Clostridium difficile toxins have been developed.

Adult spinal motoneurons remain viable despite prolonged absence of functional synaptic contact with muscle.

Several rat medial gastrocnemius (MG) motor axons were allowed to regenerate into normally innervated muscle. Under these conditions, synapse formation is known to be prevented by the existence of the original innervation of the host muscle. A study was made of the ability of the implanted spinal motoneurons to acquire and retrogradely transport horseradish peroxidase (HRP) injected into the host muscle at various postoperative intervals.

Trichohyalin: purification from porcine tongue epithelium and characterization of the native protein.

Trichohyalin, a protein of Mr between 190 and 220 kDa in different species, was first demonstrated in large granules of the inner root sheath and medulla of hair follicles and may provide a matrix for keratin filaments. We have purified trichohyalin in milligram quantities from a citric acid-insoluble fraction derived from pig tongue epithelium. Trichohyalin was extracted under conditions of low ionic strength from the citric acid-insoluble fraction, separated by gel-filtration chromatography in buffer containing 1 M NaBr, and concentrated by ion-exchange chromatography in buffer containing 4 M urea.

Cryopreservation evaluated with mitochondrial and Z line ultrastructure in striated muscle.

Single, intact, frog skeletal muscle fibres and whole frog hearts were quick-frozen on a polished, liquid-He-cooled copper block and examined in the electron microscope after freeze-substitution and freeze-fracture. In both kinds of striated muscle, collapse of the peripheral and intracristal membrane spaces in mitochondria was found to increase with increasing distance from the point of first impact (PFI) of the muscle cells on the cold copper block. The changes correlated with a previously described gradient of Z line and A band cryodamage occurring with distance from the PFI.