Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 19 de 19
Filter
Add more filters











Publication year range
1.
Phys Rev Lett ; 131(20): 201801, 2023 Nov 17.
Article in English | MEDLINE | ID: mdl-38039482

ABSTRACT

A new dark sector antibaryon, denoted ψ_{D}, could be produced in decays of B mesons. This Letter presents a search for B^{+}→ψ_{D}+p (and the charge conjugate) decays in e^{+}e^{-} annihilations at 10.58 GeV, using data collected in the BABAR experiment. Data corresponding to an integrated luminosity of 398 fb^{-1} are analyzed. No evidence for a signal is observed. Branching fraction upper limits in the range from 10^{-7}-10^{-5} are obtained at 90% confidence level for masses of 1.0

2.
Ultrasound Obstet Gynecol ; 61(6): 682-690, 2023 06.
Article in English | MEDLINE | ID: mdl-36840981

ABSTRACT

OBJECTIVES: To investigate the predictive performance of the Fetal Medicine Foundation (FMF) first-trimester screening algorithm for pre-eclampsia in a Danish population and compare screening performance with that of the current Danish strategy, which is based on maternal risk factors. METHODS: This was a prospective study of women with a singleton pregnancy attending for their first-trimester ultrasound scan and screening for aneuploidies at six Danish university hospitals between May 2019 and December 2020. Prenatal data on maternal characteristics and medical history were recorded, and measurements of mean arterial pressure (MAP), uterine artery pulsatility index (UtA-PI), serum pregnancy-associated plasma protein-A (PAPP-A) and serum placental growth factor (PlGF) were collected without performing a risk assessment for pre-eclampsia. Information on acetylsalicylic acid use was recorded. After delivery, pregnancy outcome, including gestational age at delivery and pre-eclampsia diagnosis, was recorded. Pre-eclampsia risk assessment for each woman was calculated blinded to outcome using the FMF screening algorithm following adjustment to the Danish population. Detection rates (DRs) of the FMF algorithm were calculated for a fixed screen-positive rate (SPR) of 10% and for the SPR achieved in the current Danish screening. RESULTS: A total of 8783 pregnant women were included, with a median age of 30.8 (interquartile range (IQR), 28.1-33.9) years. The majority were white (95%), naturally conceiving (90%), non-smokers (97%) and had no family history of pre-eclampsia (96%). The median body mass index was 23.4 (IQR, 21.2-26.6) kg/m2 . A complete risk assessment including maternal characteristics, MAP, UtA-PI, PlGF and PAPP-A was available for 8156 women (92.9%). In these women, UtA-PI was measured bilaterally with a median value of 1.58 (IQR, 1.27-1.94) and the median resting MAP of 80.5 (IQR, 76.1-85.4) mmHg in two consecutive measurements. Among these, 303 (3.7%) developed pre-eclampsia, including 55 (0.7%) cases of pre-eclampsia with delivery < 37 weeks of gestation and 16 (0.2%) cases of pre-eclampsia with delivery < 34 weeks. At a SPR of 10%, combined screening using the FMF algorithm based on maternal characteristics, MAP, UtA-PI, PlGF and PAPP-A had a DR of 77.4% (95% CI, 57.6-97.2%) for pre-eclampsia with delivery < 34 weeks, 66.8% (95% CI, 54.4-79.1%) for pre-eclampsia with delivery < 37 weeks and 44.1% (95% CI, 38.5-49.7%) for pre-eclampsia with delivery at any gestational age. The current Danish screening strategy using maternal risk factors detected 25.0% of women with pre-eclampsia with delivery < 34 weeks and 19.6% of women with pre-eclampsia with delivery < 37 weeks at a SPR of 3.4%. When applying the FMF algorithm including maternal characteristics, MAP, UtA-PI and PlGF at the fixed SPR of 3.4%, the DRs were 60.5% (95% CI, 36.9-84.1%) for PE with delivery < 34 weeks and 45.2% (95% CI, 32.0-58.5%) for PE with delivery < 37 weeks. CONCLUSION: In this large Danish multicenter study, the FMF algorithm based on maternal characteristics, MAP, UtA-PI, PlGF and PAPP-A predicted 77.4% of cases with pre-eclampsia with delivery < 34 weeks and 66.8% of cases with pre-eclampsia with delivery < 37 weeks of gestation at a SPR of 10%, suggesting that the performance of the algorithm in a Danish cohort matches that in other populations. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Subject(s)
Pre-Eclampsia , Prenatal Diagnosis , Pregnancy , Female , Humans , Pre-Eclampsia/epidemiology , Prospective Studies , Pregnancy-Associated Plasma Protein-A , Placenta Growth Factor , Arterial Pressure , Uterine Artery/diagnostic imaging , Biomarkers , Pulsatile Flow , Denmark/epidemiology
3.
Phys Rev Lett ; 122(8): 081802, 2019 Mar 01.
Article in English | MEDLINE | ID: mdl-30932586

ABSTRACT

We report the observation of the rare charm decay D^{0}→K^{-}π^{+}e^{+}e^{-}, based on 468 fb^{-1} of e^{+}e^{-} annihilation data collected at or close to the center-of-mass energy of the ϒ(4S) resonance with the BABAR detector at the SLAC National Accelerator Laboratory. We find the branching fraction in the invariant mass range 0.675

4.
Phys Rev Lett ; 122(7): 072002, 2019 Feb 22.
Article in English | MEDLINE | ID: mdl-30848619

ABSTRACT

Recent investigations have suggested that the six-quark combination uuddss could be a deeply bound state (S) that has eluded detection so far, and a potential dark matter candidate. We report the first search for a stable, doubly strange six-quark state in ϒ→SΛ[over ¯]Λ[over ¯] decays based on a sample of 90×10^{6}ϒ(2S) and 110×10^{6}ϒ(3S) decays collected by the BABAR experiment. No signal is observed, and 90% confidence level limits on the combined ϒ(2S,3S)→SΛ[over ¯]Λ[over ¯] branching fraction in the range (1.2-1.4)×10^{-7} are derived for m_{S}<2.05 GeV. These bounds set stringent limits on the existence of such exotic particles.

5.
Phys Rev Lett ; 119(20): 202003, 2017 Nov 17.
Article in English | MEDLINE | ID: mdl-29219353

ABSTRACT

We measure the mass difference, Δm_{+}, between the D^{*}(2010)^{+} and the D^{+} using the decay chain D^{*}(2010)^{+}→D^{+}π^{0} with D^{+}→K^{-}π^{+}π^{+}. The data were recorded with the BABAR detector at center-of-mass energies at and near the ϒ(4S) resonance, and correspond to an integrated luminosity of approximately 468 fb^{-1}. We measure Δm_{+}=(140 601.0±6.8[stat]±12.9[syst]) keV. We combine this result with a previous BABAR measurement of Δm_{0}≡m(D^{*}(2010)^{+})-m(D^{0}) to obtain Δm_{D}=m(D^{+})-m(D^{0})=(4824.9±6.8[stat]±12.9[syst]) keV. These results are compatible with and approximately five times more precise than the Particle Data Group averages.

6.
Phys Rev Lett ; 118(3): 031802, 2017 Jan 20.
Article in English | MEDLINE | ID: mdl-28157371

ABSTRACT

We search for the rare flavor-changing neutral current process B^{+}→K^{+}τ^{+}τ^{-} using data from the BABAR experiment. The data sample, collected at the center-of-mass energy of the ϒ(4S) resonance, corresponds to a total integrated luminosity of 424 fb^{-1} and to 471×10^{6} BB[over ¯] pairs. We reconstruct one B meson, produced in the ϒ(4S)→B^{+}B^{-} decay, in one of many hadronic decay modes and search for activity compatible with a B^{+}→K^{+}τ^{+}τ^{-} decay in the rest of the event. Each τ lepton is required to decay leptonically into an electron or muon and neutrinos. Comparing the expected number of background events with the data sample after applying the selection criteria, we do not find evidence for a signal. The resulting upper limit, at the 90% confidence level, is B(B^{+}→K^{+}τ^{+}τ^{-})<2.25×10^{-3}.

7.
Phys Rev Lett ; 119(13): 131804, 2017 Sep 29.
Article in English | MEDLINE | ID: mdl-29341718

ABSTRACT

We search for single-photon events in 53 fb^{-1} of e^{+}e^{-} collision data collected with the BABAR detector at the PEP-II B-Factory. We look for events with a single high-energy photon and a large missing momentum and energy, consistent with production of a spin-1 particle A^{'} through the process e^{+}e^{-}→γA^{'}; A^{'}→invisible. Such particles, referred to as "dark photons," are motivated by theories applying a U(1) gauge symmetry to dark matter. We find no evidence for such processes and set 90% confidence level upper limits on the coupling strength of A^{'} to e^{+}e^{-} in the mass range m_{A^{'}}≤8 GeV. In particular, our limits exclude the values of the A^{'} coupling suggested by the dark-photon interpretation of the muon (g-2)_{µ} anomaly, as well as a broad range of parameters for the dark-sector models.

9.
Am J Cardiol ; 79(11): 1549-52, 1997 Jun 01.
Article in English | MEDLINE | ID: mdl-9185655

ABSTRACT

Prevalence and echocardiographic characteristics of strands on the leaflets of native aortic valves were examined. According to our data, the strands we found in 39% of patients are most likely Lambl's excrescences.


Subject(s)
Aortic Valve/diagnostic imaging , Aortic Valve/pathology , Echocardiography, Transesophageal , Adult , Aged , Diagnosis, Differential , Female , Heart Valve Diseases/diagnostic imaging , Heart Valve Diseases/pathology , Humans , Male , Middle Aged , Prospective Studies
10.
Work ; 8(1): 73-5, 1997.
Article in English | MEDLINE | ID: mdl-24441782

ABSTRACT

This case report demonstrates the difficulty in treating women who are being abused within their environments. A frequent site of injury is the upper extremity. This issue may have significant effects on desired outcomes and should be properly assessed to improve intervention, return to work, and programs following discharge.

13.
Anesthesiology ; 81(6): 1516-26, 1994 Dec.
Article in English | MEDLINE | ID: mdl-7992921

ABSTRACT

BACKGROUND: Increases in brain glucose will worsen outcome after global cerebral ischemia, and some experimental evidence suggests that the duration of hyperglycemia also may influence outcome. Different types of hyperglycemia were studied to identify metabolic differences that might account for alterations in postischemic outcome. METHODS: Ninety pentobarbital-anesthetized Sprague-Dawley rats were divided into three groups: normoglycemic nondiabetic rats (N) (n = 30), chronically hyperglycemic diabetic rats (HD) (n = 30), and acutely hyperglycemic, glucose-infused nondiabetic rats (HN) (n = 30). These groups were further subdivided into groups of six rats each that received 0, 2.5, 5, 10, or 15 min of complete cerebral ischemia (potassium chloride--induced cardiac arrest). Brains were excised after 10-kW focused microwave radiation and metabolites were measured using enzymatic fluorometric techniques. RESULTS: At all study intervals, plasma glucose concentrations in HD and HN were fourfold greater than in N. Before ischemia, brain glucose concentrations in all groups were proportional to plasma glucose concentrations; however, brain glycogen concentrations did not differ among groups. After the onset of ischemia, there was an immediate diminution of brain glucose, glycogen, adenosine triphosphate (ATP), and phosphocreatine that in all cases was most pronounced during the initial 2.5 min of ischemia. Consumption of carbohydrate stores and lactate production were greater in HD and HN than in N. HD had lesser preischemic ATP concentrations and energy charges relative to N and HN (P < 0.05), perhaps reflecting their disease state; however, at 2.5 min of ischemia, the relationship of ATP concentrations and energy charges was HN > HD > N (P < 0.05 among all). In all groups, ATP and phosphocreatine were more than 96% depleted by 10 min of ischemia. With few exceptions (ATP concentrations and energy charges before ischemia and at 2.5 min, and lactate concentration in HD < HN at 15 min), there were no measured metabolic differences between HD and HN. CONCLUSIONS: In these studies, the duration of hyperglycemia did not affect intraischemic carbohydrate consumption. At short durations of ischemia (2.5 min), both HD and HN groups had greater intraischemic ATP concentrations and energy charges than N; however, at longer durations of ischemia (> 5.0 min), high-energy phosphate depletion was similarly severe in all groups. These studies suggest that energy failure is not the origin of worse postischemic neurologic injury in hyperglycemic subjects, nor does energy failure readily explain reported differences between acutely and chronically hyperglycemic subjects exposed to global cerebral ischemia.


Subject(s)
Adenine Nucleotides/metabolism , Brain Ischemia/metabolism , Brain/metabolism , Diabetes Mellitus, Experimental/metabolism , Glucose/metabolism , Glycogen/metabolism , Hyperglycemia/metabolism , Animals , Blood Glucose , Blood Pressure , Energy Metabolism , Lactates/blood , Rats , Rats, Sprague-Dawley
14.
J Pharmacol Exp Ther ; 241(3): 915-20, 1987 Jun.
Article in English | MEDLINE | ID: mdl-3298622

ABSTRACT

MDL 25,637 is a novel compound designed as a transition-state inhibitor of alpha-glucohydrolases. This compound inhibits rat intestinal sucrase, maltase, isomaltase, glucoamylase and trehalase activities at micromolar concentrations. It is a much weaker inhibitor of alpha-amylase and lactase. Inhibition of sucrase was competitive with sucrose. In mice, MDL 25,637 inhibited the rise in serum glucose after a sucrose or starch load but not after a glucose load. MDL 25,637 also reduced the glycemic response to sucrose in rats. The drug was most effective when administered 0 to 30 min before the sucrose load and was as effective in streptozotocin-treated rats as in normals. The inhibition by MDL 25,637 of intestinal glucohydrolases is an effective means of reducing the hyperglycemic response to an oral sucrose or starch load and, as such, warrants further investigation as a potential drug for the treatment of diabetes mellitus.


Subject(s)
Blood Glucose/metabolism , Disaccharidases/antagonists & inhibitors , Intestines/enzymology , Sugar Alcohols/pharmacology , Animals , Gastrointestinal Motility/drug effects , Insulin/blood , Rats
SELECTION OF CITATIONS
SEARCH DETAIL