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J Wahl

Publications and source records attributed to J Wahl.

At least 37 records · Page 2Linked to original sources
PubMed2000

Search for color singlet technicolor particles in p&pmacr; collisions at radicals = 1.8 TeV

We search for color singlet technirho and technipion production in p&pmacr; collisions at sqrt[s] = 1.8 TeV recorded with the Collider Detector at Fermilab. These exotic technimesons are present in a model of walking technicolor. The signatures studied are lepton plus two jets plus E(T) and multijet final states. No excess of events is seen in either final state. We set an upper limit on the technirho production cross section and exclude a region in the technipion mass versus technirho mass plane.

Journal Article↗
PubMed2000

Search for a fourth-generation quark more massive than the Z0 boson in p&pmacr; collisions at radicals = 1.8 TeV

We present the results of a search for pair production of a fourth-generation charge -1 / 3 quark (b(')) in sqrt[s] = 1.8 TeV p&pmacr; collisions using 88 pb(-1) of data obtained with the Collider Detector at Fermilab. We assume that both quarks decay via the flavor-changing neutral current process b(')-->bZ(0) and that the b(') mass is greater than m(Z)+m(b). We studied the decay mode b(')b(');-->Z(0)Z(0)b&bmacr; where one Z0 decays into e(+)e(-) or &mgr;(+)&mgr;(-) and the other decays hadronically, giving a signature of two leptons plus jets. An upper limit on the sigma(p&pmacr;-->b(')b(');)x[B(b(')-->bZ(0))](2) is established as a function of the b(') mass. We exclude at 95% confidence level a b(') quark with mass between 100 and 199 GeV/c(2) for B(b(')-->bZ(0)) = 100%.

Journal Article↗
PubMed2000

Transverse momentum and total cross section of e(+)e(-) pairs in the Z-boson region from p&pmacr; collisions at sqrt

The transverse momentum and total cross section of e(+)e(-) pairs in the Z-boson region of 66<M(ee)<116 GeV/c(2) from p&pmacr; collisions at sqrt[s] = 1.8 TeV are measured using 110 pb(-1) of collisions taken by the Collider Detector at Fermilab during 1992-1995. The total cross section is measured to be 248+/-11 pb. The differential transverse momentum cross section is compared with calculations that match quantum chromodynamics perturbation theory at high transverse momentum with the gluon resummation formalism at low transverse momentum.

Journal Article↗
PubMed2000

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. Assuming a standard V-A weak decay, we find that the fraction of W's with zero helicity in the top rest frame is F0 = 0.91+/-0. 37(stat)+/-0.13(syst), consistent with the standard model prediction of F0 = 0.70 for a top mass of 175 GeV/c(2).

Journal Article↗
PubMed2000

Observation of diffractive b-quark production at the fermilab tevatron

We report a measurement of the fraction of b quarks produced diffractively in &pmacr;p collisions at sqrt[s] = 1.8 TeV. Diffraction is identified by the absence of particles in a forward pseudorapidity region. From events with an electron of transverse momentum 9.5<p(e)(T)<20 GeV/ c within the pseudorapidity region |eta|<1.1, the ratio of diffractive to total b-quark production rates is found to be R(&bmacr;b) = [0.62+/-0.19(stat)+/-0.16(syst)]%. This result is comparable in magnitude to corresponding ratios for W and dijet production but significantly lower than expectations based on factorization.

Journal Article↗
PubMed2000

Same-day surgery managed care: monitoring patient and system variances.

The Same-Day Surgery (SDS) nursing staff at a Midwestern medical center tracked the causative factors for prolonged stays (> 2 hours) in SDS. A review of retrospective data identified that postoperative patient stays averaged between 2 and 3 hours. The top three variances for prolonged stays in SDS were pain, nausea and transportation home. Based on this data, several practice changes that were incorporated to address these variances are reported in this article.

Ambulatory Surgical Procedures↗
PubMed1999

High school health teachers' perceived self-efficacy in identifying students at risk for suicide.

A national random sample of 228 high school health teachers completed a 45-item survey to examine their perceived self-efficacy regarding adolescent suicide. Most respondents were female, White, and held master's degrees. Most believed it was their role to recognize students at risk for suicide, believed that if they did recognize students at risk it would reduce the chances that the student would commit suicide, and believed that one of the most important things they could do would be to prevent a suicidal student from committing suicide. However, only 9% believed they could recognize a student at risk for suicide. High efficacy expectations scores were associated with working at a school that offered an inservice program on adolescent suicide, included teaching about suicide prevention in the curriculum, and had a crisis intervention team. This study suggests that teacher health education programs should spend more time on developing the skills necessary to identify students at risk. In addition, a comprehensive school suicide prevention program is strongly encouraged for all high schools.

Adolescent↗
PubMed1995

Importance of communication training for psychiatric residents and mental health trainees.

Through the illustration of a clinical vignette and excerpts from interviews with trainees, this paper suggests that communication and communication disorders are essential issues in child psychiatry training. The vignette shows how communication issues pervade a multidisciplinary psychoeducational day treatment program. The importance of communication in the clinical experience and its impact on the professional preparation of psychiatry residents and mental health trainees are examined, and conclusions and recommendations for the goals of a training program in child psychiatry are presented which expand upon those findings.

Child↗
PubMed1993

P- and E-cadherin are in separate complexes in cells expressing both cadherins.

E- and P-cadherin are members of a family of calcium-dependent, cell surface glycoproteins involved in cell-cell adhesion. Extracellularly, the transmembrane cadherins self-associate, while intracellularly, they interact with the actin-based cytoskeleton. Several intracellular proteins, collectively termed catenins, are tightly associated with E- and P-cadherin. These proteins appear to link the cadherin to the cytoskeleton and have been proposed to be involved in concentrating cadherins at cell-cell adherens junctions. In this paper we report the production of monoclonal antibodies against both alpha- and beta-catenin and use these antibodies to show that in cells simultaneously expressing two different cadherins, E-cadherin and P-cadherin, each cadherin appears to be present in a separate cadherin/catenin complex.

Antibodies, Monoclonal↗
PubMed1992

A multicenter, randomized, double-blind, placebo-controlled trial of pimobendan, a new cardiotonic and vasodilator agent, in patients with severe congestive heart failure.

Pimobendan, a new oral cardiotonic and vasodilator agent, increases myocardial contractile force through specific inhibition of phosphodiesterase type III and increased calcium sensitivity of the myocardial contractile elements. The effects of pimobendan on left ventricular performance and maximal exercise capacity were studied in a multicenter, randomized, double-blind, placebo-controlled trial involving 52 patients with severe congestive heart failure despite diuretics, digoxin, and angiotensin-converting enzyme inhibitors. The acute hemodynamic evaluation included three single doses of 2.5, 5.0, and 10.0 mg of oral pimobendan, which was subsequently administered at a daily dose of 5 or 10 mg for 4 weeks. Acute administration of pimobendan significantly increased the resting cardiac index and lowered pulmonary capillary wedge pressure in a dose-dependent manner, whereas heart rate and systemic arterial pressure were not substantially altered. Patients receiving pimobendan, 5 and 10 mg daily, had a significantly greater increase in maximal exercise duration than those receiving placebo, that is, 144 +/- 30 and 124 +/- 33 seconds versus 58 +/- 25 seconds (p = 0.05). Peak oxygen uptake increased by 1.7 +/- 0.8 and 2.2 +/- 1.3 ml/kg/min in patients receiving pimobendan at a daily dose of 5 and 10 mg, respectively, whereas it decreased by 0.1 +/- 0.6 ml/kg/min in patients receiving placebo (p = 0.06). Thus pimobendan acutely improves resting left ventricular performance and chronically increases exercise duration and peak oxygen uptake in patients with severe congestive heart failure concomitantly treated with digoxin, diuretics, and angiotensin-converting enzyme inhibitors.

Cardiotonic Agents↗
PubMed1991

Identification of a receptor protein for neuropeptide Y in rabbit kidney. G-protein association and inhibition of adenylate cyclase.

We previously identified the receptor for neuropeptide Y (NPY) on rabbit kidney membranes as a 100 kDa protein [(1990) J. Biol. Chem. 265, 18142-18143]. It is demonstrated in this study that the stable guanine nucleotide analogue, guanosine 5'-O-(3-thiotriphosphate) (GTP gamma S), is capable of decreasing the labeling of the 100 kDa protein in a concentration-dependent manner, with an IC50 value of 50 microM. This suggests that the 100 kDa protein represents a G-protein coupled receptor type. In isolated proximal tubules from rabbit kidney NPY decreases the parathyroid hormone stimulated cAMP production in a dose-dependent fashion. This indicates that the NPY receptor in rabbit kidney is negatively coupled to adenylate cyclase by a G1-like protein.

Adenylyl Cyclases↗
PubMed1989

Specific phosphodiesterase inhibition and maximal and submaximal exercise performance in patients with congestive heart failure.

The current therapeutic interest in specific phosphodiesterase (PDE) inhibition involves patients with severe congestive heart failure (CHF) whose symptoms are not controlled by diuretics, nitrates, angiotensin converting enzyme (ACE) inhibitors, and digitalis. Maximal exercise capacity is limited in these patients by an inadequate rise in cardiac output and a fixed capacity to dilate the skeletal muscle vasculature, which is perhaps compounded by disorders of the skeletal muscle metabolism. To improve maximal exercise capacity, the increase in cardiac performance produced by specific phosphodiesterase inhibitors must, in turn, reverse the abnormalities present in the periphery, and more specifically augment the capacity to dilate the skeletal muscle vasculature. Increased vasodilatory response to maximal exercise probably depends on the regression of structural changes in the skeletal muscle vasculature. Such regression may be mediated by a reduction in neurohormonal vasoconstrictor stimuli and/or chronic augmentation in resting limb blood flow. Submaximal exercise capacity, at work loads equivalent to less than 70% of peak aerobic capacity, appears to be directly limited by depressed cardiac output and high sympathetic vasoconstrictor activity. Specific phosphodiesterase inhibition, which consistently increases left ventricular performance during exercise, is more likely to improve exercise capacity at submaximal work loads than at maximal work loads.

Exercise↗
PubMed1986

Comparative hypotensive effects of acebutolol and hydrochlorothiazide in patients with mild to moderate essential hypertension: a double-blind multicenter evaluation.

A double-blind multicenter study compared oral acebutolol (n = 182) with hydrochlorothiazide (n = 178) in the treatment of mild to moderate essential hypertension (diastolic blood pressure 95 to 114 mm Hg). Both agents produced significant and comparable reductions in systolic, diastolic, and mean arterial blood pressures of 15.9, 14.9, and 15.3 mm Hg on acebutolol, and 15.2, 13.3, and 11.8 mm Hg on hydrochlorothiazide (p = 0.001). Acebutolol induced a significant reduction in resting heart rate of 9.3 bpm (p = 0.001) from baseline. The mean effective doses of acebutolol and hydrochlorothiazide were 757 and 68 mg, respectively. Significantly fewer patients on acebutolol experienced arrhythmia, anorexia, and flatulence, although an equal number of patients (14) in each group discontinued therapy prematurely due to side effects. More hydrochlorothiazide-treated patients developed abnormalities in the levels of serum glucose, uric acid, blood urea nitrogen (BUN), serum potassium, and chloride. No clinically significant trends in laboratory parameters were seen on acebutolol, although a small number of patients (11 on acebutolol and 3 on hydrochlorothiazide) developed asymptomatic positive antinuclear antibody (ANA) tests of low titer. The data show that acebutolol is as effective as hydrochlorothiazide in the treatment of hypertension, is as well tolerated, and produces fewer biochemical abnormalities.

Acebutolol↗
PubMed1986

[Spinal anesthesia with hyperbaric tetracaine and bupivacaine: velocity of spread, analgesic effect and motor blockade in various positions and injection volumes].

The effect of Trendelenburg position (5 degrees head-down) for 60 or 45 s on the spread of hyperbaric 0.5% tetracaine and 0.5% bupivacaine (3 or 4 ml) was studied in 80 patients scheduled for urological surgery. The mean spread of analgesia was faster (p less than 0.05) and greater (p less than 0.05) in patients tilted head-down for 45 s receiving 4 ml tetracaine than in those with 3 ml tetracaine and 60 s Trendelenburg position. With bupivacaine corresponding results of both volumes, 3 or 4 ml, were similar. Tetracaine compared with bupivacaine showed a faster cephalad spread with 4 ml (p less than 0.05) but not with 3 ml. The onset time of motor blockade in all groups was short (less than 10 min) and complete (Bromage III). The results prove that 4 ml of 0.5% tetracaine with 5% Trendelenburg position for 45 s ensure a rapid and safe spread of analgesia with adequate motor blockade for transurethral surgery.

Aged↗
PubMed1985

Comparison of acebutolol and propranolol in essential hypertension.

A multicenter, double-blind study compared oral acebutolol (n = 186) with propranolol (n = 190) in the treatment of mild to moderately severe essential hypertension (diastolic greater than or equal to 95 to 129 mm Hg). Both beta blockers produced significant and comparable reductions in diastolic, systolic, and mean arterial blood pressures of 16%, 12%, and 14% on acebutolol and 15%, 12%, and 14% on propranolol (all p less than 0.01). At equipotent, antihypertensive doses, acebutolol induced significantly less reduction in resting heart rate than propranolol (13% on acebutolol, 17% on propranolol, p = 0.02). The mean effective doses of acebutolol and propranolol were 738 mg and 231 mg, respectively. Significantly fewer acebutolol patients experienced central nervous system side effects (acebutolol, n = 50; propranolol, n = 75; p = 0.01) or withdrew from the study prematurely due to side effects (acebutolol, n = 11; propranolol, n = 29; p less than 0.01). No clinically significant trends in abnormalities of laboratory parameters were seen, and there were no statistically significant differences in the development of positive antinuclear antibody titers between the two treatment groups. It is concluded that acebutolol is as effective as propranolol in the treatment of hypertension, and acebutolol was better tolerated on the basis of heart rate and central nervous system side effects.

Acebutolol↗
PubMed1981

[A contribution towards metrical sex determination of cremated and uncremated human bone remains, worked out at the pars petrosa ossis temporalis (author's transl)].

A new method for sex diagnosis is presented; the uni-, di-, and multivariate analysis of the Pars petrosa, which is a part of the temporal bone. This work was initiated because the Pars petrosa can be found very often among human cremation remains. Two different discriminant functions were worked out, and their comparison shows the great value of considering all the characteristics. Consideration of three measurements can give a sex determination of remarkable accuracy (about 80%). Even the uni- and divariate examinations yield important leads. The last part of this work deals with the possibility of applying the method to cremated bones. The most important point to consider is the shrinking of burnt bones. Appropriate new mean values of the first three measurements and an adapted sectioning point are given. Yet, even without shrinkage-correction the functions possess great reliability in the application on cremated material.

Adult↗