Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 71
Filter
2.
Phys Rev Lett ; 128(13): 132501, 2022 Apr 01.
Article in English | MEDLINE | ID: mdl-35426696

ABSTRACT

We report the first measurement of the parity-violating elastic electron scattering asymmetry on ^{27}Al. The ^{27}Al elastic asymmetry is A_{PV}=2.16±0.11(stat)±0.16(syst) ppm, and was measured at ⟨Q^{2}⟩=0.02357±0.00010 GeV^{2}, ⟨θ_{lab}⟩=7.61°±0.02°, and ⟨E_{lab}⟩=1.157 GeV with the Q_{weak} apparatus at Jefferson Lab. Predictions using a simple Born approximation as well as more sophisticated distorted-wave calculations are in good agreement with this result. From this asymmetry the ^{27}Al neutron radius R_{n}=2.89±0.12 fm was determined using a many-models correlation technique. The corresponding neutron skin thickness R_{n}-R_{p}=-0.04±0.12 fm is small, as expected for a light nucleus with a neutron excess of only 1. This result thus serves as a successful benchmark for electroweak determinations of neutron radii on heavier nuclei. A tree-level approach was used to extract the ^{27}Al weak radius R_{w}=3.00±0.15 fm, and the weak skin thickness R_{wk}-R_{ch}=-0.04±0.15 fm. The weak form factor at this Q^{2} is F_{wk}=0.39±0.04.

3.
Phys Rev Lett ; 125(11): 112502, 2020 Sep 11.
Article in English | MEDLINE | ID: mdl-32976004

ABSTRACT

A beam-normal single-spin asymmetry generated in the scattering of transversely polarized electrons from unpolarized nucleons is an observable related to the imaginary part of the two-photon exchange process. We report a 2% precision measurement of the beam-normal single-spin asymmetry in elastic electron-proton scattering with a mean scattering angle of θ_{lab}=7.9° and a mean energy of 1.149 GeV. The asymmetry result is B_{n}=-5.194±0.067(stat)±0.082 (syst) ppm. This is the most precise measurement of this quantity available to date and therefore provides a stringent test of two-photon exchange models at far-forward scattering angles (θ_{lab}→0) where they should be most reliable.

5.
Plant Dis ; 103(3): 468-474, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30632471

ABSTRACT

In 2017, potato tubers suspected of being infected with the bacterium 'Candidatus Liberibacter solanacearum' were received from the Animal and Plant Health Inspection Service in the United States. A total of 368 chipping tubers were observed for internal symptoms of zebra chip disease, which is associated with 'Ca. L. solanacearum' infection in the United States, Mexico, Central America, and New Zealand. A single tuber sliced at the stem end showed classic zebra chip symptoms of darkened medullary rays, with streaking and necrotic flecking. The symptomatic tuber was confirmed positive for the bacterium by polymerase chain reaction targeting three different 'Ca. L. solanacearum' genes. Sequence analysis of these three genes, and subsequent BLAST analysis, identified the pathogen with 99, 98, and 97% identity to 'Ca. L. solanacearum' for the 16S ribosomal RNA gene, 50S ribosomal proteins L10/L12 genes, and the outer membrane protein gene, respectively. Sequence analysis did not identify the sample as one of the six known haplotypes of 'Ca. L. solanacearum,' indicating that a seventh haplotype of the pathogen was identified. This new haplotype, designated haplotype F, is now the third haplotype of the bacterium that infects Solanum tuberosum in the United States.


Subject(s)
Haplotypes , Rhizobiaceae , Solanum tuberosum , Animals , Genes, Bacterial/genetics , Plant Diseases/microbiology , Rhizobiaceae/classification , Rhizobiaceae/genetics , Solanum tuberosum/microbiology
6.
Internist (Berl) ; 59(6): 618-629, 2018 06.
Article in German | MEDLINE | ID: mdl-29619572

ABSTRACT

A number of rare cardiac diseases can be recognized by electrocardiogram (ECG). This article illustrates the clinical importance of ECG as a key diagnostic tool to detect Wolff-Parkinson-White syndrome and channelopathies, which are frequently diagnosed late after one or more affected family members have become victims of sudden cardiac death. These channelopathies include long QT syndrome, short QT syndrome, Brugada syndrome, and catecholaminergic polymorphic ventricular tachycardia. In addition, typical ECG findings are frequently present in patients with idiopathic ventricular tachycardia, arrhythmogenic right ventricular dysplasia, digitalis intoxication, hyperkalemia, acute cor pulmonale due to pulmonary embolism, as well as severe left ventricular hypertrophy as in hypertrophic cardiomyopathy.


Subject(s)
Brugada Syndrome , Electrocardiography , Long QT Syndrome , Tachycardia, Ventricular , Arrhythmias, Cardiac/diagnosis , Brugada Syndrome/diagnosis , Death, Sudden, Cardiac , Humans , Long QT Syndrome/diagnosis , Tachycardia, Ventricular/diagnosis
7.
Psychol Med ; 47(7): 1179-1191, 2017 May.
Article in English | MEDLINE | ID: mdl-27998319

ABSTRACT

BACKGROUND: The public health, public safety and clinical implications of violent events among adults with mental illness are significant; however, the causes and consequences of violence and victimization among adults with mental illness are complex and not well understood, which limits the effectiveness of clinical interventions and risk management strategies. This study examined interrelationships between violence, victimization, psychiatric symptoms, substance use, homelessness and in-patient treatment over time. METHOD: Available data were integrated from four longitudinal studies of adults with mental illness. Assessments took place at baseline, and at 1, 3, 6, 9, 12, 15, 18, 24, 30 and 36 months, depending on the parent studies' protocol. Data were analysed with the autoregressive cross-lag model. RESULTS: Violence and victimization were leading indicators of each other and affective symptoms were a leading indicator of both. Drug and alcohol use were leading indicators of violence and victimization, respectively. All psychiatric symptom clusters - affective, positive, negative, disorganized cognitive processing - increased the likelihood of experiencing at least one subsequent symptom cluster. Sensitivity analyses identified few group-based differences in the magnitude of effects in this heterogeneous sample. CONCLUSIONS: Violent events demonstrated unique and shared indicators and consequences over time. Findings indicate mechanisms for reducing violent events, including trauma-informed therapy, targeting internalizing and externalizing affective symptoms with cognitive-behavioral and psychopharmacological interventions, and integrating substance use and psychiatric care. Finally, mental illness and violence and victimization research should move beyond demonstrating concomitant relationships and instead focus on lagged effects with improved spatio-temporal contiguity.


Subject(s)
Crime Victims/statistics & numerical data , Hospitalization/statistics & numerical data , Ill-Housed Persons/statistics & numerical data , Mental Disorders/epidemiology , Violence/statistics & numerical data , Adult , Humans , Mental Disorders/therapy
8.
Phys Rev Lett ; 111(14): 141803, 2013 Oct 04.
Article in English | MEDLINE | ID: mdl-24152148

ABSTRACT

The Q(weak) experiment has measured the parity-violating asymmetry in ep elastic scattering at Q(2)=0.025(GeV/c)(2), employing 145 µA of 89% longitudinally polarized electrons on a 34.4 cm long liquid hydrogen target at Jefferson Lab. The results of the experiment's commissioning run, constituting approximately 4% of the data collected in the experiment, are reported here. From these initial results, the measured asymmetry is A(ep)=-279±35 (stat) ± 31 (syst) ppb, which is the smallest and most precise asymmetry ever measured in ep scattering. The small Q(2) of this experiment has made possible the first determination of the weak charge of the proton Q(W)(p) by incorporating earlier parity-violating electron scattering (PVES) data at higher Q(2) to constrain hadronic corrections. The value of Q(W)(p) obtained in this way is Q(W)(p)(PVES)=0.064±0.012, which is in good agreement with the standard model prediction of Q(W)(p)(SM)=0.0710±0.0007. When this result is further combined with the Cs atomic parity violation (APV) measurement, significant constraints on the weak charges of the up and down quarks can also be extracted. That PVES+APV analysis reveals the neutron's weak charge to be Q(W)(n)(PVES+APV)=-0.975±0.010.

9.
Phys Rev Lett ; 111(8): 082501, 2013 Aug 23.
Article in English | MEDLINE | ID: mdl-24016222

ABSTRACT

We report on parity-violating asymmetries in the nucleon resonance region measured using inclusive inelastic scattering of 5-6 GeV longitudinally polarized electrons off an unpolarized deuterium target. These results are the first parity-violating asymmetry data in the resonance region beyond the Δ(1232). They provide a verification of quark-hadron duality-the equivalence of the quark- and hadron-based pictures of the nucleon-at the (10-15)% level in this electroweak observable, which is dominated by contributions from the nucleon electroweak γZ interference structure functions. In addition, the results provide constraints on nucleon resonance models relevant for calculating background corrections to elastic parity-violating electron scattering measurements.

10.
Eur J Clin Microbiol Infect Dis ; 32(11): 1483-9, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23733319

ABSTRACT

To determine the spread of Staphylococcus aureus within and between nursing home (NH) residents in the Euregion Meuse-Rhine, a cross-border region of the Netherlands and Germany, we investigated the prevalence of antibiotic resistance, genetic background and population structure of both methicillin-susceptible S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) isolates. A total of 245 S. aureus isolates were collected from NH residents. Susceptibility testing was performed with microbroth dilution. The genetic background was determined using spa typing, SCCmec typing, pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Differences in the prevalence of resistance between the German and Dutch MSSA isolates were observed for the macrolides (15 % vs. 2 %, p = 0.003), clindamycin (15 % vs. 0 %, p = 0.003) and ciprofloxacin (34 % vs. 25 %). The macrolide and ciprofloxacin resistance varied between the NHs, while trimethoprim-sulfamethoxazole resistance was low in all residents. The MRSA prevalence was 3.5 % and <1 % among the German and Dutch NH residents, respectively (p = 0.005). The German MRSAs, isolated in 7 out of 10 NHs, belonged to ST22-MRSA-IV or ST225-MRSA-II. spa clonal complexes (spa-CCs) 015 and 002 were prevalent among the German MSSA isolates and spa-CCs 024 and 1716 were prevalent among the Dutch MSSA isolates. The antibiotic resistance of MSSA and the MRSA prevalence were significantly higher among the German NH residents. The spread of two MRSA clones was observed within and between the German NHs, but not between the Dutch and German NHs. Differences in the prevalence of resistance and the prevalence of MRSA between NHs on both sides of the border warrant the continuation of surveillance at a local level.


Subject(s)
Cross Infection/epidemiology , Drug Resistance, Bacterial , Nursing Homes , Staphylococcal Infections/epidemiology , Staphylococcus aureus/classification , Staphylococcus aureus/drug effects , Anti-Bacterial Agents/pharmacology , Cross Infection/microbiology , Drug Resistance, Microbial , Genotype , Germany/epidemiology , Humans , Microbial Sensitivity Tests , Molecular Epidemiology , Molecular Typing , Netherlands/epidemiology , Staphylococcal Infections/microbiology , Staphylococcus aureus/genetics , Staphylococcus aureus/isolation & purification
11.
Phys Rev Lett ; 108(10): 102001, 2012 Mar 09.
Article in English | MEDLINE | ID: mdl-22468841

ABSTRACT

The parity-violating cross-section asymmetry in the elastic scattering of polarized electrons from unpolarized protons has been measured at a four-momentum transfer squared Q2 = 0.624 GeV2 and beam energy E(b) = 3.48 GeV to be A(PV) = -23.80 ± 0.78(stat) ± 0.36(syst) parts per million. This result is consistent with zero contribution of strange quarks to the combination of electric and magnetic form factors G(E)(s) + 0.517G(M)(s) = 0.003 ± 0.010(stat) ± 0.004(syst) ± 0.009(ff), where the third error is due to the limits of precision on the electromagnetic form factors and radiative corrections. With this measurement, the world data on strange contributions to nucleon form factors are seen to be consistent with zero and not more than a few percent of the proton form factors.

12.
Chirurg ; 82(7): 625-30, 2011 Jul.
Article in German | MEDLINE | ID: mdl-21161142

ABSTRACT

BACKGROUND: Pelvic exenteration for advanced or recurrent rectal cancer often results in complex defects associated with high complication rates and morbidity for the patients. The goal of therapy is therefore restoration of functional stability and adequate soft tissue coverage, thus enhancing the quality of life with limited life expectancy by an interdisciplinary approach. PATIENTS AND METHODS: We report on eight patients treated by combined interdisciplinary pelvic exenteration with resection of the sacrum and subsequent coverage of the pelvic floor defect with free latissimus dorsi muscle flaps. All patients were treated in two stages according to a pre-established therapeutic algorithm. First, an abdominal and transsacral pelvic exenenteration was performed with an ileostomy and ileum conduit system and the pelvic floor was closed with vicryl meshes. The open wound was optimized by vacuum-assisted closure (VAC) therapy before reconstruction of the pelvic floor was undertaken 10-12 days later with free latissimus dorsi musculocutaneous flaps either anastomosed to the lower or upper gluteal vessels or to an AV-loop using the saphenous vein as connection to the groin vessels. RESULTS: In all cases a sufficient and stable reconstruction of the pelvic floor could be achieved and no flap loss occurred. In three patients a minor wound dehiscence occurred, which could be closed by secondary suture. The time span between the free flap transfer and stable wound closure was 19-28 days. Later complications such as fistula formation and chronic wound infections were not observed. The survival of the patients ranged from 10-36 months. CONCLUSION: The present two-stage concept of pelvic floor reconstruction with free latissimus dorsi muscle flaps for wound closure after pelvic exenteration improves postoperative morbidity and mortality and increases the quality of life of the affected patients. A shortened period of open wound therapy brings additional economic benefits. Because of its anatomical features the free latissimus dorsi flap can be regarded as the method of choice of microsurgical reconstruction within an interdisciplinary concept after pelvic exenteration.


Subject(s)
Cooperative Behavior , Interdisciplinary Communication , Microsurgery/methods , Neoplasm Recurrence, Local/surgery , Patient Care Team , Pelvic Exenteration/methods , Plastic Surgery Procedures/methods , Postoperative Complications/etiology , Postoperative Complications/prevention & control , Quality of Life , Rectal Neoplasms/surgery , Aged , Disease-Free Survival , Female , Free Tissue Flaps/blood supply , Humans , Male , Middle Aged , Negative-Pressure Wound Therapy , Neoplasm Recurrence, Local/mortality , Neoplasm Recurrence, Local/pathology , Neoplasm Staging , Postoperative Complications/mortality , Rectal Neoplasms/mortality , Rectal Neoplasms/pathology , Sacrum/surgery
13.
Dtsch Med Wochenschr ; 135(27): 1368-71, 2010 Jul.
Article in German | MEDLINE | ID: mdl-20589583

ABSTRACT

HISTORY AND ADMISSION FINDINGS: A 39-year-old woman was admitted for the treatment of recurrent septicemia, corrosive esophageal and gastric mucosal injury, and bloody stools. INVESTIGATIONS: A search of her hospital room provided evidence of a self-inflicted disorder. Bacteremia with typical fecal flora had been caused by self-injected intravenous inoculation of stool and the esophageal ulcers by swallowed vinegar. TREATMENT AND COURSE: The patient was initially treated with meropenem. After initial clinical and psychological stabilization the patient refused further psychiatric or psychosomatic treatment. CONCLUSION: Fluctuating or bizarre symptoms and unusual diagnostic findings may indicate self-inflicted disorders, in which the symptoms of illness are caused by the afflicted person him/herself.


Subject(s)
Acetic Acid/toxicity , Bacterial Infections/diagnosis , Burns, Chemical/diagnosis , Duodenum/injuries , Esophagus/injuries , Factitious Disorders/diagnosis , Gastric Mucosa/injuries , Intestinal Mucosa/injuries , Sepsis/diagnosis , Adult , Bacterial Infections/psychology , Endoscopy, Digestive System , Factitious Disorders/psychology , Female , Fever of Unknown Origin , Gastrointestinal Hemorrhage/diagnosis , Gastrointestinal Hemorrhage/psychology , Humans , Occult Blood , Patient Care Team , Recurrence , Referral and Consultation , Sepsis/psychology
14.
Int J STD AIDS ; 21(3): 166-71, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20215619

ABSTRACT

Regimen selection in antiretroviral therapy can impact treatment adherence, quality of life (QoL) and treatment satisfaction, and may influence clinical outcome. We evaluated the effect of regimen switching on virological, safety and patient-reported outcomes. In this 48-week, open-label, randomized, non-inferiority study, 262 HIV-1-infected adult patients with a viral load <50 copies/mL on protease inhibitor (PI)-based regimens were switched to either once-daily efavirenz, lamivudine and enteric-coated didanosine (efavirenz-A [QD]) or once-daily efavirenz plus continuation of current nucleoside reverse transcriptase inhibitors (efavirenz-B). In the primary outcome of patients who maintained virological suppression at week 48, efavirenz-A (QD) was non-inferior to efavirenz-B (81% versus 79%, respectively). Both regimens were associated with low virological failure rates and significant improvements in treatment satisfaction, adherence and QoL after switching from PI-based therapy, with no differences between regimens. Switching from a PI- to an efavirenz-based regimen was generally safe and well tolerated.


Subject(s)
Benzoxazines/therapeutic use , HIV Infections/drug therapy , HIV Protease Inhibitors/therapeutic use , HIV-1 , Reverse Transcriptase Inhibitors/therapeutic use , Adult , Alkynes , Antiretroviral Therapy, Highly Active , CD4 Lymphocyte Count , Cyclopropanes , Didanosine/therapeutic use , Female , HIV Infections/immunology , HIV Infections/virology , Humans , Lamivudine/therapeutic use , Male , Patient Compliance , Patient Satisfaction , Quality of Life , Treatment Outcome , United States , Viral Load
15.
J Clin Pathol ; 63(2): 177-9, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20154041

ABSTRACT

Mesenchymal neoplasms of the gallbladder are rare, and most represent sarcomas of various histological types. To our knowledge, only a few patients with multiple Epstein-Barr virus (EBV)-associated smooth muscle tumours of the gallbladder in the setting of immunodeficiency have been reported in the English literature, but no single case of conventional leiomyoma has been well documented to date. A case of gallbladder leiomyoma in a healthy 34-year-old woman is described here. The tumour was found incidentally on a routine ultrasound examination and was removed by simple cholecystectomy. The patient is alive and well at last follow-up, 6 months after surgery. Histology and immunohistochemistry were consistent with a benign smooth muscle neoplasm that is very similar to conventional uterine leiomyoma. The tumour was negative for both EBV-encoded nuclear RNAs and EBV latent membrane antigen. The patient had no history of uterine leiomyoma or other neoplasms or clinical evidence of an immune defect. Leiomyoma should be included in the differential diagnosis of spindle cell tumours of the gallbladder and must be distinguished from leiomyosarcoma and the rare gastrointestinal stromal tumour-like neoplasms reported recently at this unusual anatomical site.


Subject(s)
Gallbladder Neoplasms/diagnosis , Leiomyoma/diagnosis , Adult , Diagnosis, Differential , Female , Gallbladder Neoplasms/pathology , Humans , Leiomyoma/pathology
16.
Phys Rev Lett ; 105(26): 262302, 2010 Dec 31.
Article in English | MEDLINE | ID: mdl-21231649

ABSTRACT

The electric form factor of the neutron was determined from studies of the reaction 3He(e,e'n)pp in quasielastic kinematics in Hall A at Jefferson Lab. Longitudinally polarized electrons were scattered off a polarized target in which the nuclear polarization was oriented perpendicular to the momentum transfer. The scattered electrons were detected in a magnetic spectrometer in coincidence with neutrons that were registered in a large-solid-angle detector. More than doubling the Q2 range over which it is known, we find G(E)(n)=0.0236±0.0017(stat)±0.0026(syst), 0.0208±0.0024±0.0019, and 0.0147±0.0020±0.0014 for Q(2)=1.72, 2.48, and 3.41 GeV2, respectively.

17.
Phys Rev Lett ; 99(9): 092301, 2007 Aug 31.
Article in English | MEDLINE | ID: mdl-17930999

ABSTRACT

We have measured the beam-normal single-spin asymmetry in elastic scattering of transversely polarized 3 GeV electrons from unpolarized protons at Q2=0.15, 0.25 (GeV/c)2. The results are inconsistent with calculations solely using the elastic nucleon intermediate state and generally agree with calculations with significant inelastic hadronic intermediate state contributions. A(n) provides a direct probe of the imaginary component of the 2gamma exchange amplitude, the complete description of which is important in the interpretation of data from precision electron-scattering experiments.

18.
Phys Rev Lett ; 98(3): 032301, 2007 Jan 19.
Article in English | MEDLINE | ID: mdl-17358678

ABSTRACT

We report new measurements of the parity-violating asymmetry A(PV) in elastic scattering of 3 GeV electrons off hydrogen and 4He targets with approximately 6.0 degrees . The 4He result is A(PV)=(+6.40+/-0.23(stat)+/-0.12(syst))x10(-6). The hydrogen result is A(PV)=(-1.58+/-0.12(stat)+/-0.04(syst))x10(-6). These results significantly improve constraints on the electric and magnetic strange form factors G(E)(s) and G(M)(s). We extract G(E)(s)=0.002+/-0.014+/-0.007 at =0.077 GeV2, and G(E)(s)+0.09G(M)(s)=0.007+/-0.011+/-0.006 at =0.109 GeV2, providing new limits on the role of strange quarks in the nucleon charge and magnetization distributions.

19.
Br J Sports Med ; 40 Suppl 1: i48-54, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16799104

ABSTRACT

BACKGROUND AND OBJECTIVES: Glucocorticosteroids are widely used in medicine and have shown unchallenged therapeutic potential in several chronic inflammatory and other diseases. They are also widely used in sports medicine for the treatment of conditions such as asthma and acute injuries. In fact, as banned substances, most requests for therapeutic use exemption concern glucocorticosteroids. Nevertheless, their beneficial effect in certain conditions in sports, where inflammation is only a secondary reaction, remains to be validated. This paper aimed to provide a comprehensive review of the literature covering the therapeutic use of glucocorticosteroids since 1977 in conditions ranging from chronic rheumatic illness to peritendinous or intra-articular injection in acute injuries. METHODS: Search of the medical literature published between 1977 and 2006 using PubMed. Articles relevant to the question "When and if at all is the use of glucocorticosteroids justified in football?" were selected and analysed. RESULTS AND CONCLUSIONS: The findings clearly point out that, despite the common use of glucocorticosteroids in acute injuries in sports, there is actually limited evidence of the true benefits of such a practice. Physicians must take the possible adverse effects into consideration. In an athlete with clinically verified asthma, inhalational glucocorticosteroids remain first line therapy. Finally, for the purposes of education and prevention of misuse, it should be stressed that a measurable performance enhancing effect of glucocorticoids could not be proved on the basis of the results of the scientific studies to date.


Subject(s)
Athletic Injuries/drug therapy , Doping in Sports/prevention & control , Glucocorticoids/administration & dosage , Soccer/injuries , Glucocorticoids/pharmacokinetics , Humans
20.
Phys Rev Lett ; 95(9): 092001, 2005 Aug 26.
Article in English | MEDLINE | ID: mdl-16197209

ABSTRACT

We have measured parity-violating asymmetries in elastic electron-proton scattering over the range of momentum transfers 0.12 < or =Q2 < or =1.0 GeV2. These asymmetries, arising from interference of the electromagnetic and neutral weak interactions, are sensitive to strange-quark contributions to the currents of the proton. The measurements were made at Jefferson Laboratory using a toroidal spectrometer to detect the recoiling protons from a liquid hydrogen target. The results indicate nonzero, Q2 dependent, strange-quark contributions and provide new information beyond that obtained in previous experiments.

SELECTION OF CITATIONS
SEARCH DETAIL
...