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1.
Plant Dis ; : PDIS04230770RE, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38301222

RESUMO

Phoma black stem (PBS), caused by Phoma macdonaldii Boerema (teleomorph Leptosphaeria lindquistii Frezzi), is the most common stem disease of sunflower (Helianthus annuus L.) in the northern Great Plains region of the United States. However, the impact of PBS on sunflower yield in the United States is unclear, and a near complete absence of information on the impact of fungicides on disease management exists. The objectives of this study were to determine the impact of PBS on sunflower yield, the efficacy of available fungicides, the optimal fungicide application timing, and the economic viability of fungicides as a management tool. Fungicide timing efficacy was evaluated by applying single and/or sequential applications of pyraclostrobin fungicide at three sunflower growth stages in 10 field trials between 2017 and 2019. Efficacy of 10 fungicides from the Fungicide Resistance Action Committee (FRAC) groups 3, 7, and 11 were evaluated in four field trials between 2018 and 2019. The impact of treatments on PBS were evaluated by determination of incidence, severity, maximum lesion height, disease severity index (DSI), and harvested yield. Nine of the 10 fungicides evaluated and all fungicide timings that included an early bud application resulted in disease reductions when compared with the nontreated controls. The DSI was negatively correlated to sunflower yield in high-yield environments (P = 0.0004; R2 = 0.3425) but not in low- or moderate-yield environments. Although FRAC 7 fungicides were generally most efficacious, the sufficient efficacy and lower cost of FRAC 11 fungicides make them more economically viable in high-yielding environments at current market conditions.

2.
Phys Rev Lett ; 128(13): 132002, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35426724

RESUMO

The first measurement of lepton-jet momentum imbalance and azimuthal correlation in lepton-proton scattering at high momentum transfer is presented. These data, taken with the H1 detector at HERA, are corrected for detector effects using an unbinned machine learning algorithm (multifold), which considers eight observables simultaneously in this first application. The unfolded cross sections are compared with calculations performed within the context of collinear or transverse-momentum-dependent factorization in quantum chromodynamics as well as Monte Carlo event generators.

3.
Science ; 380(6641): 198-203, 2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37053312

RESUMO

Direct imaging of gas giant exoplanets provides information on their atmospheres and the architectures of planetary systems. However, few planets have been detected in blind surveys with direct imaging. Using astrometry from the Gaia and Hipparcos spacecraft, we identified dynamical evidence for a gas giant planet around the nearby star HIP 99770. We confirmed the detection of this planet with direct imaging using the Subaru Coronagraphic Extreme Adaptive Optics instrument. The planet, HIP 99770 b, orbits 17 astronomical units from its host star, receiving an amount of light similar to that reaching Jupiter. Its dynamical mass is 13.9 to 16.1 Jupiter masses. The planet-to-star mass ratio [(7 to 8) × 10-3] is similar to that of other directly imaged planets. The planet's atmospheric spectrum indicates an older, less cloudy analog of the previously imaged exoplanets around HR 8799.

4.
Eur Phys J C Part Fields ; 77(11): 791, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-31997933

RESUMO

The strong coupling constant α s is determined from inclusive jet and dijet cross sections in neutral-current deep-inelastic ep scattering (DIS) measured at HERA by the H1 collaboration using next-to-next-to-leading order (NNLO) QCD predictions. The dependence of the NNLO predictions and of the resulting value of α s ( m Z ) at the Z-boson mass m Z are studied as a function of the choice of the renormalisation and factorisation scales. Using inclusive jet and dijet data together, the strong coupling constant is determined to be α s ( m Z ) = 0.1157 ( 20 ) exp ( 29 ) th . Complementary, α s ( m Z ) is determined together with parton distribution functions of the proton (PDFs) from jet and inclusive DIS data measured by the H1 experiment. The value α s ( m Z ) = 0.1142 ( 28 ) tot obtained is consistent with the determination from jet data alone. The impact of the jet data on the PDFs is studied. The running of the strong coupling is tested at different values of the renormalisation scale and the results are found to be in agreement with expectations.

5.
J Gen Physiol ; 117(2): 103-18, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11158164

RESUMO

Tyrosine side chains participate in several distinct signaling pathways, including phosphorylation and membrane trafficking. A nonsense suppression procedure was used to incorporate a caged tyrosine residue in place of the natural tyrosine at position 242 of the inward rectifier channel Kir2.1 expressed in Xenopus oocytes. When tyrosine kinases were active, flash decaging led both to decreased K(+) currents and also to substantial (15-26%) decreases in capacitance, implying net membrane endocytosis. A dominant negative dynamin mutant completely blocked the decaging-induced endocytosis and partially blocked the decaging-induced K(+) channel inhibition. Thus, decaging of a single tyrosine residue in a single species of membrane protein leads to massive clathrin-mediated endocytosis; in fact, membrane area equivalent to many clathrin-coated vesicles is withdrawn from the oocyte surface for each Kir2.1 channel inhibited. Oocyte membrane proteins were also labeled with the thiol-reactive fluorophore tetramethylrhodamine-5-maleimide, and manipulations that decreased capacitance also decreased surface membrane fluorescence, confirming the net endocytosis. In single-channel studies, tyrosine kinase activation decreased the membrane density of active Kir2.1 channels per patch but did not change channel conductance or open probability, in agreement with the hypothesis that tyrosine phosphorylation results in endocytosis of Kir2.1 channels. Despite the Kir2.1 inhibition and endocytosis stimulated by tyrosine kinase activation, neither Western blotting nor (32)P labeling produced evidence for direct tyrosine phosphorylation of Kir2.1. Therefore, it is likely that tyrosine phosphorylation affects Kir2.1 function indirectly, via interactions between clathrin adaptor proteins and a tyrosine-based sorting motif on Kir2.1 that is revealed by decaging the tyrosine side chain. These interactions inhibit a fraction of the Kir2.1 channels, possibly via direct occlusion of the conduction pathway, and also lead to endocytosis, which further decreases Kir2.1 currents. These data establish that side chain decaging can provide valuable time-resolved data about intracellular signaling systems.


Assuntos
Ativação do Canal Iônico/fisiologia , Canais de Potássio Corretores do Fluxo de Internalização , Canais de Potássio/genética , Canais de Potássio/metabolismo , Transporte Proteico/fisiologia , Tirosina/metabolismo , Animais , Clatrina/metabolismo , Dinaminas , Condutividade Elétrica , Endocitose/fisiologia , Corantes Fluorescentes , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo , Oócitos/fisiologia , Técnicas de Patch-Clamp , Fosforilação , Potássio/metabolismo , Canais de Potássio/química , Proteínas Tirosina Quinases/metabolismo , Rodaminas , Xenopus
6.
Thromb Haemost ; 79(3): 567-70, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9531042

RESUMO

Very little data is available assessing the clinical utility of coagulation-based APC resistance assays compared to DNA-based analysis for the factor V Leiden mutation in children. Therefore, the clinical utility of four aPTT-based assays for APC resistance was evaluated in 169 children, ages 3 months through 16 years. The prevalence of the Arg506 to Gln mutation was 7/169 (4.1%). Using cutoff points derived from the normal PCR-screened population (n = 162), two assays for APC resistance (APC-SR and n-APC-SR) gave poor concordance with the PCR assay (sensitivity 29% and 57%, respectively). Two modified assays (FDAPC-SR and n-FDAPC-SR), in which patient plasma was prediluted 1:5 in factor V deficient plasma, gave excellent concordance (sensitivity 100%). The predictive value of a positive test was 0.25, 0.44, 1.00 and 0.88 for the APC-SR, n-APC-SR, FDAPC-SR and n-FDAPC-SR, respectively. The FDAPC-SR and n-FDAPC-SR tests gave excellent discrimination using cutoff values derived from the total population (n = 169) without regard to previous PCR screening results.


Assuntos
Testes de Coagulação Sanguínea , Resistência a Medicamentos , Proteína C/farmacologia , Adolescente , Criança , Pré-Escolar , Humanos , Lactente , Valor Preditivo dos Testes , Sensibilidade e Especificidade
7.
Am J Clin Pathol ; 76(1): 43-9, 1981 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7020407

RESUMO

The importance of the incorporation of microbiology information into the laboratory cumulative report implies that continuing efforts need to be made to enhance the readability and style of such reports. In addition, the optimizing of laboratory work flow around a computer record-keeping system in microbiology is essential to guarantee technologist satisfaction with and usage of the system. The efforts and results of extending a commercially available system in the microbiology laboratory are discussed and compared with another approach using the same system base. The project led to smooth laboratory work flow and highly successful combined reports. Necessary software modifications are summarized.


Assuntos
Computadores , Sistemas de Informação , Laboratórios/organização & administração , Técnicas Microbiológicas , Coleta de Dados , Registros
8.
Cancer Genet Cytogenet ; 44(2): 253-62, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2153441

RESUMO

This article discusses the results of cytogenetic investigations of a cell line derived from a malignant tumor arising in a benign salivary gland pleomorphic adenoma. Initial karyotypic studies became possible with cells of the second in vitro passage and revealed the existence of hypertetraploidy. Furthermore, a marked polysomy 7 and a translocation involving 12q13-15, a breakpoint also frequently seen in benign pleomorphic adenomas, were noteworthy. During long term culture, the number of chromosomes per cell decreased as well as the number of copies of chromosome 7. Cell tumorigenicity was proved by heterotransplantation to nude mice. The resulting tumors were karyotyped again. No significant changes of the chromosome number or of the degree of polysomy 7 were found compared to the cells before heterotransplantation. In contrast, the cells from the nude mice tumors showed a remarkable number of different isochromosomes probably indicating an unknown factor supporting the generation of isochromosomes. The consistent presence of the t(12;?)(q13-15;?) makes the cell line well suited for molecular studies of this breakpoint region.


Assuntos
Adenoma Pleomorfo/genética , Carcinoma/genética , Aberrações Cromossômicas , Neoplasias das Glândulas Salivares/genética , Adenoma Pleomorfo/patologia , Animais , Carcinoma/patologia , Bandeamento Cromossômico , Marcadores Genéticos , Humanos , Cariotipagem , Camundongos , Camundongos Nus , Transplante de Neoplasias , Neoplasias das Glândulas Salivares/patologia , Transplante Heterólogo , Células Tumorais Cultivadas
9.
Rofo ; 165(4): 349-52, 1996 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-8963046

RESUMO

PURPOSE: To compare the x-ray images made by the Kodak InSight Pediatric Imaging System (InSight P) with conventional film-screen systems in pediatric chest radiography. MATERIAL AND METHODS: The comparison involved chest radiographs made using Quanta-Fast-Detail/Cronex 4 (DuPont), Trimax 16/XDA (3 M) and DuPont UVR/UVL systems. The image quality of critical structures and the physical parameters of quantum interference, contrast and resolution were assessed. The energy path of the system was assessed by preparing density curves. Test conditions were in accordance with the latest guidelines of the Bundesärztekammer (German Physician's Association). RESULTS: The mediastinal area, retrocardiac and paravertebral spaces and the peripheral vessels of the lung were all displayed more distinctly using InSight P. The reason for this seems to be a lower degree of quantum interference associated with this system. With tube voltages between 60 and 80 kV, InSight P displayed a relatively low degree of sensitivity. CONCLUSION: InSight P can be used to produce predominantly high quality chest radiographs of infants between one and five years of age. However, this system has limited sensitivity in the tube voltage range recommended by the German Physicians' Association.


Assuntos
Radiografia Torácica/instrumentação , Ecrans Intensificadores para Raios X , Fatores Etários , Pré-Escolar , Estudos de Avaliação como Assunto , Humanos , Lactente , Sensibilidade e Especificidade
10.
Psychiatr Serv ; 48(1): 102-4, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9117488

RESUMO

Acute treatment records of all medical and surgical patients evacuated to Walter Reed Army Medical Center in Washington, D.C., from the Persian Gulf theater (N = 161) were examined to better understand the relationship of injury to psychiatric symptoms. A total of 110 (68 percent) sustained a traumatic injury. They were significantly more likely to have an axis I disorder or psychiatric symptoms of concern than participants in the Persian Gulf War who did not sustain traumatic injuries but who were evacuated for medical conditions. The results indicate that traumatically injured veterans are at greater risk of psychiatric symptoms than veterans who are not injured and that they should be referred for psychiatric evaluation.


Assuntos
Distúrbios de Guerra/epidemiologia , Veteranos/estatística & dados numéricos , Guerra , Ferimentos por Arma de Fogo/epidemiologia , Adolescente , Adulto , Distúrbios de Guerra/psicologia , Feminino , Humanos , Oceano Índico , Masculino , Pessoa de Meia-Idade , Equipe de Assistência ao Paciente , Fatores de Risco , Veteranos/psicologia , Ferimentos por Arma de Fogo/psicologia
11.
Hepatogastroenterology ; 28(2): 99-101, 1981 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7216156

RESUMO

It has been demonstrated that acute thioacetamide intoxication causes a significant increase in copper and zinc in the dystrophic liver of rats. Heart, skeletal muscle, cerebrum and cerebellum showed neither significant deviations of copper and zinc content, nor noticeable histopathologic changes in comparison with controls. Thus, hepatotropia in thioacetamide intoxication receives minimal pathological confirmation.


Assuntos
Acetamidas/intoxicação , Cobre/análise , Fígado/análise , Tioacetamida/intoxicação , Zinco/análise , Animais , Química Encefálica , Masculino , Músculos/análise , Miocárdio/análise , Ratos
12.
IEEE Trans Inf Technol Biomed ; 3(4): 252-60, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10719475

RESUMO

The CRIGOS (compact robot for image-guided orthopedic surgery) project was set up for the development of a compact surgical robot system for image-guided orthopedic surgery based on user requirements. The modular system comprises a compact parallel robot and a software system for planning of the surgical interventions and for supervision of the robotic device. Because it is not sufficient to consider only technical aspects in order to improve in clinical routine the therapeutic outcome of conventional interventions, a user-centered and task-oriented design process has been developed which also takes human factors into account. The design process for the CRIGOS system was started from requirement analysis of various orthopedic interventions using information gathered from literature, questionnaires, and workshops with domain experts. This resulted in identification of conventional interventions for which the robotic system would improve the medical and procedural quality. A system design concept has been elaborated which includes definitions of components, functionalities, and interfaces. Approaches to the acquisition of calibrated X-rays will be presented in the paper together with design and evaluation of a first human-computer interface. Finally, the first labtype parallel robot based on low-cost standard components is presented together with the first evaluation results concerning positioning accuracy.


Assuntos
Ortopedia , Robótica , Terapia Assistida por Computador , Humanos , Raios X
13.
Chirurg ; 57(11): 741-5, 1986 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-3542424

RESUMO

Because of the risk of carcinoma, choledochal cysts always should be completely removed. If the cyst is extrahepatic, this should not offer any problem. Radical excision of an intrahepatic cyst, however, can present as a major problem and is in fact not always achievable. The anatomical situation (involvement of both lobes of the liver) or the general condition of a patient can force us to limit the surgical procedure. We report our experience with 5 cases of intrahepatic choledochal cyst, emphasizing the difficulties of achieving the before mentioned therapeutic goal. Details on today's pathogenetic theories and classification of choledochal cysts are reported from the literature.


Assuntos
Doenças dos Ductos Biliares/cirurgia , Ductos Biliares Intra-Hepáticos/cirurgia , Cistos/cirurgia , Idoso , Idoso de 80 Anos ou mais , Doenças dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/patologia , Cistos/patologia , Feminino , Hepatectomia , Humanos , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Ultrassonografia
14.
Urologe A ; 14(6): 306-14, 1975 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-1108341

RESUMO

Rats fed abnormally composed isocaloric diets during 21 days (low magnesium, atherogenous, high in proteins or carbohydrates) develop a mean increase in total number of pancreatic A cells, a significant increase of A/B ratio (atherogenous), and hyperglucagonemia in most of the groups under study. Histologic examination reveals calcification most marked in animals under low magnesium and atherogenous diets. They are only scarce following high protein diet; a normal or carbohydrate rich diet nullifies this phenomenon. Independent of the morphologic and functional state of the islets, supplementation by argining and histidine of normal chow is followed by a certain degree of renal calcification. Lowered urinary magnesium and calcium and elevated urinary sodium and phosphate together with a tendency toward hypercalcemia point to stimulation of parathyroids during malnutrition. Absolute or relative hyperglucagonemia must be considered the main causstive factor.


Assuntos
Dieta , Glucagon/sangue , Ilhotas Pancreáticas , Nefrocalcinose/etiologia , Animais , Arginina , Glicemia , Cálcio/urina , Dieta Aterogênica , Carboidratos da Dieta , Proteínas Alimentares , Histidina , Insulina/sangue , Ilhotas Pancreáticas/patologia , Magnésio/urina , Deficiência de Magnésio , Masculino , Fosfatos/urina , Projetos Piloto , Estudos Prospectivos , Ratos , Sódio/urina
15.
Adolescence ; 15(60): 807-22, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-7211541

RESUMO

A five day weight management camp for adolescents is described. Three components of weight management comprise of the camp's educational basis: 1) Nutrition Education, 2) Behavior Modeling, and 3) Physical Activity. Program planning and organizational methods are described. Thirty-five teenagers, age 13-17, attended the program. The mean weight loss for camp participants, measured at six months after camp, was 3.3 pounds. Triceps skinfold measurements showed an average decrease of 3.6mm after three months. The Wahler Self-Description Inventory was administered to measure favorable and unfavorable attributes through a self-evaluation process. Results showed a steady and continuous increase in favorable scores through the course of the camp and at the time of follow-up. Unfavorable scores were high prior to camp, followed by a sudden drop in unfavorable scores after the week of supportive therapy, followed by a leaving off effect of the 3-month follow-up session. A program evaluation by camp participants revealed that the residential camp environment was a useful approach to adolescent weight management therapy.


Assuntos
Acampamento , Obesidade/terapia , Tratamento Domiciliar , Adolescente , Terapia Comportamental , Dieta Redutora/psicologia , Feminino , Processos Grupais , Humanos , Masculino , Obesidade/psicologia , Esforço Físico , Autoimagem
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