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1.
Phys Rev Lett ; 132(22): 221801, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38877905

RESUMO

Higgsinos with masses near the electroweak scale can solve the hierarchy problem and provide a dark matter candidate, while detecting them at the LHC remains challenging if their mass splitting is O(1 GeV). This Letter presents a novel search for nearly mass-degenerate Higgsinos in events with an energetic jet, missing transverse momentum, and a low-momentum track with a significant transverse impact parameter using 140 fb^{-1} of proton-proton collision data at sqrt[s]=13 TeV collected by the ATLAS experiment. For the first time since LEP, a range of mass splittings between the lightest charged and neutral Higgsinos from 0.3 to 0.9 GeV is excluded at 95% confidence level, with a maximum reach of approximately 170 GeV in the Higgsino mass.

2.
Opt Express ; 29(2): 2624-2636, 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33726454

RESUMO

We have developed an extreme ultraviolet (XUV) frequency comb for performing ultra-high precision spectroscopy on the many XUV transitions found in highly charged ions (HCI). Femtosecond pulses from a 100 MHz phase-stabilized near-infrared frequency comb are amplified and then fed into a femtosecond enhancement cavity (fsEC) inside an ultra-high vacuum chamber. The low-dispersion fsEC coherently superposes several hundred incident pulses and, with a single cylindrical optical element, fully compensates astigmatism at the w0 = 15 µm waist cavity focus. With a gas jet installed there, intensities reaching ∼ 1014 W/cm2 generate coherent high harmonics with a comb spectrum at 100 MHz rate. We couple out of the fsEC harmonics from the 7th up to the 35th (42 eV; 30 nm) to be used in upcoming experiments on HCI frequency metrology.

3.
Opt Lett ; 45(8): 2156-2159, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32287180

RESUMO

We raise the power from a commercial 10 W frequency comb inside an enhancement cavity and perform multi-photon ionization of gas-phase atoms at 100 MHz for the first time, to the best of our knowledge. An intra-cavity velocity-map-imaging setup collects electron-energy spectra of xenon at rates several orders of magnitude higher than those of conventional laser systems. Consequently, we can use much lower intensities ${\sim}{{10}^{12}} \;{\rm W}/{{\rm cm}^2} $∼1012W/cm2 without increasing acquisition times above just a few seconds. The high rate and coherence of the stabilized femtosecond pulses are known to be transferred to the actively stabilized cavity and will allow studying purely perturbative multi-photon effects, paving the road towards a new field of precision tests in nonlinear physics.

4.
Transfus Apher Sci ; 51(3): 44-52, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25457007

RESUMO

An audit was performed at a tertiary hospital in Bloemfontein, South Africa, to establish whether clinicians adhered to local platelet transfusion guidelines. The audit showed poor compliance with local guidelines, with 34% of platelet transfusions not aligned with guidelines and 29.9% of transfusions administered to patients with platelet counts of ≥ 150 × 10(9)/L. When compared to medical disciplines, surgical disciplines tended significantly more to transfuse platelets inappropriately (17.1% and 53.7%, respectively; p < 0.0001). Documentation was poor and in 48.4% of orders for platelets, the indication for the platelet transfusion was not clearly stated. Considerable cost could be avoided with improved adherence to guidelines. This study emphasises the need for improving education in transfusion medicine amongst medical doctors. It is hoped that the information gleaned from this study would assist in the design of educational programmes in transfusion medicine as we attempt to close the existing gaps in knowledge and skills in the field, while ensuring that blood is transfused in a cost-effective and appropriate manner.


Assuntos
Auditoria Médica , Transfusão de Plaquetas/economia , Centros de Atenção Terciária/economia , Adolescente , Adulto , Idoso , Custos e Análise de Custo , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Estudos Retrospectivos , África do Sul
5.
J Anesth ; 27(6): 815-21, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23748552

RESUMO

BACKGROUND: Hypoxemia caused by difficulties in airway management presents a major cause for perioperative morbidity and mortality. The ability to predict difficult laryngoscopy more accurately would enable anesthesiologists to take specific precautions to reduce airway risks and prevent patient-threatening events. METHODS: Over a 6-year period of time, all anesthesia records with a documented direct laryngoscopic view were retrieved from the electronic data management system and statistically processed. The Cormack-Lehane four-point scale of grading laryngoscopy was used to assess visibility of the vocal cords. RESULTS: Of 102,306 cases, the overall rate of difficult laryngoscopy was 4.9 %. Male gender (6.5 %), Mallampati score III and IV (17.3 %), obesity with a BMI ≥35 kg/m(2) (6.1 %), as well as physical status ASA III or IV (6.2 %), were identified as risk factors for difficult laryngoscopy. Patients undergoing surgery in the departments of oromaxillofacial (8.9 %), ear nose throat surgery (ENT) (7.4 %), and cardiac surgery (7.0 %) showed the highest rates of difficult laryngoscopy. CONCLUSIONS: The results indicate that the risk for difficult airway situations might substantially differ between surgical patient groups. In hospitals with departmental structures and spatially separated operating rooms, the deduction might be increased awareness and particular structural preparation for difficult airway situations in the respective subspecialties.


Assuntos
Anestesia Geral/efeitos adversos , Anestesia Geral/métodos , Hipóxia/fisiopatologia , Laringoscopia/efeitos adversos , Laringoscopia/métodos , Adulto , Idoso , Anestesia Geral/estatística & dados numéricos , Feminino , Humanos , Incidência , Laringoscopia/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Assistência Perioperatória/métodos , Estudos Retrospectivos
6.
Psychol Rep ; 124(6): 2795-2821, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33076765

RESUMO

Research on cognitive ability is done in different paradigms. In the Piagetian paradigm, cognitive ability focuses on cognitive development along qualitative stages. Interactive real scenarios, "Piagetian tasks", are constructed for measurement. According to age, tasks differing in complexity are applied in individual measurements. In the psychometric paradigm, the investigation of cognitive ability focuses on individual differences. Intelligence is seen as a quantitative construct with gradual differences between persons and ages. Paper-and-pencil tests with items differing in difficulty are used for IQ measurement of single persons or school classes. However, do those tasks measure two distinct cognitive abilities? Solving tasks in both approaches requires basic (speed, working memory) and complex cognitive abilities (reasoning, understanding). Regarding empirical relationships, we used three Austrian samples (in kindergarten four to six years old N = 40, in primary school six to eight years old N = 40, and nine to ten years old N = 41). They were tested with psychometric tests (Raven CPM or SPM) and Piagetian tasks. In addition, mental speed (ZVT) was measured in the two school samples. The average observed correlation between IQ and Piagetian tasks was r = .51. In factor analyses, the tests loaded on a common factor of general intelligence. Further analyses revealed that mental speed is correlated more strongly with psychometric (r = .50) than with Piagetian tasks (r = .39), while Piagetian tasks are more related to parental education indicators (speed: r = .11, Raven: r = .20, Piaget: r = .25).


Assuntos
Cognição , Inteligência , Criança , Pré-Escolar , Humanos , Testes de Inteligência , Resolução de Problemas , Psicometria , Instituições Acadêmicas
7.
Front Psychol ; 11: 1571, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32719644

RESUMO

Intelligence requires sufficient working-memory capacity. Traditionally, working memory was seen as a process and as a prerequisite for fluid intelligence. Working memory was assumed to be determined by maturation and health. There is a gap in the literature: It is still not fully understood to which extent and how working memory can be influenced. So this study tested how visual impairment and the extent of visual impairment are related to working memory capacity. In our study we compared N = 249 children (6-16 years) with and without visual impairment (blind, visually impaired, and sighted) in two countries (South Africa and Austria) at different development levels on their working-memory capacity and verbal comprehension. Using the WISC-IV, blind and visually impaired children showed higher working-memory capacity than sighted children (r = + 0.35, 14, and 3 IQ points, respectively). On the other hand, visually impaired children showed a weakness in verbal comprehension (r = -0.39, on average 13 IQ points lower). The pattern remained robust when SES and race-ethnicity were controlled. Our natural (quasi-)experiment shows a pattern, which is unlikely to be genetic, and so supports the view that working memory and intelligence scores can be modified.

8.
Value Health ; 17(7): A422, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27201075
9.
Neuron ; 14(2): 287-301, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7857639

RESUMO

The development of the adult central nervous system of Drosophila requires a precise and reproducible pattern of neuroblast proliferation during postembryonic neurogenesis. We show here that mutations in the minibrain (mnb) gene cause an abnormal spacing of neuroblasts in the outer proliferation center (opc) of larval brain, with the implication that mnb opc neuroblasts produce less neuronal progeny than do wild type. As a consequence, the adult mnb brain exhibits a specific and marked size reduction of the optic lobes and central brain hemispheres. The insufficient number of distinct neurons in mnb brains is correlated with specific abnormalities in visual and olfactory behavior. The mnb gene encodes a novel, cell type-specific serine-threonine protein kinase family that is expressed and required in distinct neuroblast proliferation centers during postembryonic neurogenesis. The mnb kinases share extensive sequence similarities with kinases involved in the regulation of cell division.


Assuntos
Proteínas de Drosophila , Drosophila melanogaster/fisiologia , Genes de Insetos , Sistema Nervoso/enzimologia , Proteínas Quinases/biossíntese , Proteínas Serina-Treonina Quinases/biossíntese , Sequência de Aminoácidos , Animais , Sequência de Bases , Primers do DNA , DNA Complementar , Drosophila melanogaster/embriologia , Embrião não Mamífero/enzimologia , Embrião não Mamífero/fisiologia , Gânglios dos Invertebrados/enzimologia , Gânglios dos Invertebrados/fisiologia , Expressão Gênica , Humanos , Camundongos , Dados de Sequência Molecular , Sistema Nervoso/embriologia , Sistema Nervoso/crescimento & desenvolvimento , Reação em Cadeia da Polimerase , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Tirosina Quinases , Mapeamento por Restrição , Homologia de Sequência de Aminoácidos , Quinases Dyrk
10.
Urologe A ; 46(9): 1242-7, 2007 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-17665162

RESUMO

INTRODUCTION AND OBJECTIVES: Laser therapy of symptomatic benign prostatic hyperplasia (BPH) remains a challenge for most urologic surgeons. The main goal of laser surgery is to achieve a marked volume reduction and to decrease bladder outlet obstruction and lower urinary tract symptoms with minimal morbidity. Laser therapy encompasses a variety of techniques using different laser wavelengths, application systems, and surgical techniques to achieve contrasting tissue effects. In an in vitro animal model we compared the vaporization and coagulation effects of the potassium-titanyl-phosphate (KTP) laser, holmium:yttrium-aluminum-garnet (Ho:YAG) laser, and diode laser (980 nm). MATERIAL AND METHODS: In an in vitro model using isolated perfused porcine kidneys we investigated the vaporization, the coagulation effect, and the bleeding rate of the KTP, Ho:YAG, and diode lasers on five porcine kidneys each. The application of each laser type was standardized. The area of laser application was 1 cm x 1 cm. The KTP group received an application with 80 W, the Ho:YAG group an application with 10-30 W, and the diode group an application with 30, 60, and 100 W. Hemostasis was measured semiquantitatively. Ablation and coagulation were investigated macro- and microscopically. RESULTS: Concerning the ablation capacity, the diode laser is most effective (more than fivefold) compared to the KTP and Ho:YAG lasers but demonstrated a rather large coagulation zone of up to tenfold in comparison to the KTP and Ho:YAG lasers. Semiquantitatively, in terms of bleeding rate, all lasers were equivalent in this ex vivo model. CONCLUSIONS: Our very early and limited experience indicates that KTP (80 W) and Ho:YAG (30 W) laser application are equivalent in terms of tissue ablation capacity and coagulation in an experimental setting. The diode laser at 980 nm is superior in terms of ablation capacity but has a large coagulation zone. Concerning the bleeding rate all tested lasers are equivalent in this ex vivo model.


Assuntos
Rim/cirurgia , Fotocoagulação a Laser/instrumentação , Terapia a Laser/instrumentação , Lasers de Estado Sólido/uso terapêutico , Animais , Desenho de Equipamento , Humanos , Técnicas In Vitro , Rim/patologia , Masculino , Hiperplasia Prostática/cirurgia , Suínos , Ressecção Transuretral da Próstata/instrumentação
11.
Br J Pharmacol ; 124(2): 291-8, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9641545

RESUMO

1. The aim of the present study was to determine the effect of nitric oxide (NO) on angiotensin-converting enzyme (ACE) activity. 2. A biochemical study was performed in order to analyse the effect of the NO-donors, SIN-1 and diethylamine/NO (DEA/NO), and of an aqueous solution of nitric oxide on the ACE activity in plasma from 3-month old male Sprague-Dawley rats and on ACE purified from rabbit lung. SIN-1 significantly inhibited the activity of both enzymes in a concentration-dependent way between 1 and 100 microM. DEA/NO inhibited the activity of purified ACE from 0.1 microM to 10 microM and plasma ACE, with a lower potency, between 1 and 100 microM. An aqueous solution of NO (100 and 150 microM) also inhibited significantly the activity of both enzymes. Lineweaver-Burk plots indicated an apparent competitive inhibition of Hip-His-Leu hydrolysis by NO-donors. 3. Modulation of ACE activity by NO was also assessed in the rat carotid artery by comparing contractions elicited by angiotensin I (AI) and AII. Concentration-response curves to both peptides were performed in arteries with endothelium in the presence of the guanylyl cyclase inhibitor, ODQ (10 microM), and the inhibitor of NO formation, L-NAME (0.1 mM). NO, which is still released from endothelium in the presence of 10 microM ODQ, elicited a significant inhibition of AI contractions at low concentrations (1 and 5 nM). In the absence of endothelium, 1 microM SIN-1 plus 10 microM ODQ, as well as 10 microM DEA/NO plus 10 microM ODQ induced a significant inhibition on AI-induced contractions at 1 and 5 nM and at 1-100 nM, respectively. 4. In conclusion, we demonstrated that (i) NO and NO-releasing compounds inhibit ACE activity in a concentration-dependent and competitive way and that (ii) NO release from endothelium physiologically reduces conversion of AI to AII.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Dietilaminas/farmacologia , Inibidores Enzimáticos/farmacologia , Molsidomina/análogos & derivados , Óxido Nítrico/farmacologia , Peptidil Dipeptidase A/sangue , Angiotensina I/metabolismo , Angiotensina II/metabolismo , Animais , Artérias Carótidas/efeitos dos fármacos , Artérias Carótidas/enzimologia , Relação Dose-Resposta a Droga , Guanilato Ciclase/antagonistas & inibidores , Masculino , Molsidomina/farmacologia , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/enzimologia , Óxido Nítrico/sangue , Oligopeptídeos/metabolismo , Oxidiazóis/farmacologia , Quinoxalinas/farmacologia , Coelhos , Ratos , Ratos Sprague-Dawley
12.
AIDS Res Hum Retroviruses ; 7(4): 417-21, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2069821

RESUMO

The diversity of human immunodeficiency virus type 1 (HIV-1) is mainly caused by mutations that affect the gene encoding the gp120 envelope protein. Isolates differ to a large extent in the hypervariable regions of gp120. This study was undertaken to determine the degree of variation of HIV-1 env genes isolated from seven individuals with hemophilia B who became infected in association with administration of a suspected clotting factor lot. Two hypervariable regions and part of a constant region from proviral DNA of the peripheral blood leukocytes of these patients were amplified and the products of the polymerase chain reactions were sequenced. The sequences derived from five of the individuals displayed 100% sequence homology, 1 had two and 1 had six deviations from the consensus sequence. The alignment of the amino acid sequence so deduced revealed no comparable homology to any of these two hypervariable regions from a number of published isolates. The genetic variability of HIV-1 seems to be limited, at least in the early phase of infection, allowing the determination of close relationships between epidemiologically related strains.


Assuntos
Genes env/genética , HIV-1/genética , Hemofilia B/microbiologia , Sequência de Aminoácidos , Sequência de Bases , DNA Viral/genética , Eletroforese em Gel de Poliacrilamida , Variação Genética , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Provírus/genética , Homologia de Sequência do Ácido Nucleico
13.
Int J Food Microbiol ; 76(1-2): 63-73, 2002 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-12038579

RESUMO

Malt has a complex microbial population, which changes as the malting process commences. Little is known about the proliferation of lactic acid bacteria (LAB) in each of the malting phases. In this study, we determined the number of LAB present in the different phases of malting with Clipper and Prisma barley cultivars. The strains were identified to species level by using numerical analysis of total soluble cell protein patterns, RAPD-PCR banding patterns and 16S rRNA sequencing. The number of viable LAB in the barley before steep was higher in Prisma than Clipper (7.6 x 10(4) and 1.2 x 10(3) cfu/g, respectively). Despite this, the number of viable cells recorded in the first steep water was slightly higher for Clipper (9.0 x 10(5) cfu/g) than Prisma (5.5 x 10(5) cfu/g). More or less, the same cell numbers were recorded for the two barley cultivars after the first and second dry stands. Both cultivars displayed more or less the same cell numbers (3.7 x 10(7) for Clipper and 3.2 x 10(7) cfu/g for Prisma) after the third day of germination. However, a higher number of LAB were detected in the kilned Prisma malt (6.9 x 10(4) cfu/g) than the Clipper malt (1.5 x 10(4) cfu/g). Leuconostoc argentinum, Le. lactis and Weissella confusa were the most predominant in both cultivars. A few strains were identified as W. paramesenteroides (four strains), Lactobacillus casei (five strains), Lactococcus lactis (five strains) and Lb. rhamnosus (two strains). Lb. casei and Lb. rhamnosus were not isolated from the Prisma cultivar, while W. paramesenteroides and Lc. lactis were absent in the Clipper cultivar. Kilned malt of the Clipper cultivar contained predominantly Le. argentinum, whereas the Prisma cultivar contained mainly Lc. lactis. To our knowledge. this is the first report of LAB in Clipper and Prisma barley and the various malting phases. The influence of the various groups of lactic acid bacteria on the fermenting ability of brewers' yeast is currently being determined.


Assuntos
Hordeum/microbiologia , Lactobacillus/crescimento & desenvolvimento , Contagem de Colônia Microbiana , Fermentação , Microbiologia de Alimentos , Lactobacillus/classificação , Lactobacillus/genética , Lactobacillus/isolamento & purificação , Filogenia , RNA Ribossômico 16S/análise , Técnica de Amplificação ao Acaso de DNA Polimórfico
14.
Rofo ; 185(5): 467-73, 2013 May.
Artigo em Alemão | MEDLINE | ID: mdl-23519903

RESUMO

PURPOSE: MRI examinations in children under sedation or general anesthesia are a multidisciplinary challenge for pediatric, radiology and anesthesiology departments. This article presents findings about patient population, anesthesiology procedures and process times in pediatric MRI procedures under sedation or general anesthesia. The analysis is focused on the potential to optimize process times. MATERIALS AND METHODS: Retrospectively over a 5-year period, data from diagnostic radiology procedures in children requiring sedation or general anesthesia were retrieved from anesthesia records and analyzed statistically. RESULTS: The median anesthesia time in patients without an airway device was 6 min. In patients with a laryngeal mask (19 min) and in patients receiving endotracheal intubation (20 min), the anesthesia time was significantly longer (p < 0.001). The need for airway management in the age groups was 67 % for neonates, 25 % for infants, 8 % for toddlers and 7 % for school children. Improved clinical pathways could potentially save additional time up to 69 hours in our period of investigation. CONCLUSION: In relation to older children, toddlers, infants and neonates had the longest process times in diagnostic radiology procedures, caused by the need to secure the airway. Improved pre-MRI processes have an enormous potential to generate additional examination time.


Assuntos
Manuseio das Vias Aéreas/estatística & dados numéricos , Anestesia Geral/estatística & dados numéricos , Sedação Consciente/estatística & dados numéricos , Imageamento por Ressonância Magnética/estatística & dados numéricos , Carga de Trabalho/estatística & dados numéricos , Adolescente , Criança , Pré-Escolar , Feminino , Alemanha/epidemiologia , Humanos , Lactente , Recém-Nascido , Masculino , Fatores de Tempo
15.
Ophthalmologe ; 109(9): 888-96, 2012 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-22740015

RESUMO

BACKGROUND: This study was carried out to test the reliability of a defined cut-off value for retinal thickness with estimation of the sensitivity, specificity and formation of an edema index in comparison to retinal thickness. MATERIALS AND METHODS: This was a single center prospective clinical non-blinded study of 100 eyes, including 22 eyes with central vein or branch vein occlusions, 20 eyes with diabetic macular edema, 6 eyes with postoperative macular edema, 2 eyes with uveitis and 50 healthy eyes. Detection of macular edema was carried out by third generation optical coherence tomography. Using the latest version of the Heidelberg retina tomograph (HRT 3) series of five images were produced and evaluated. The 9-zone circle of the HRT was used as the analysis contour. RESULTS: The reliability of measuring retinal thickness with the HRT in the subjects showed an intraclass correlation between 0.248 and 0.740 and patients with macular edema showed values between 0.515 and 0.949. The reliability of the edema index with the HRT in the subjects showed an intraclass correlation between 0.461 and 0.826 and patients with macular edema showed values between 0.383 and 0.826. The calculated cut-off values were between 285 µm and 360 µm. The corresponding sensitivity values were between 74.7% and 95.9% with a corresponding specificity of 74.7-90.2%. There was also a highly significant correlation between the edema index and retinal thickness (p < 0.001). CONCLUSIONS: The retina module of the latest generation HRT is capable of reproducible measurement of the retinal thickness in micrometers. The defined cut-off values correspond to expectations and can be used in this form in the clinical practice.


Assuntos
Edema Macular/patologia , Microscopia Confocal/instrumentação , Retina/patologia , Retinoscópios , Tomografia/instrumentação , Adulto , Idoso , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tomografia/métodos
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