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1.
Plant Dis ; 2024 Feb 01.
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 (NGP) region of the United States (US). However, the impact of PBS on sunflower yield in the US 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 ten field experiments between 2017 and 2019. Efficacy of ten fungicides from FRAC groups 3, 7, and 11 were evaluated in four field experiments between 2018 and 2019. The impact of treatments on PBS were evaluated by determination of incidence, severity, maximum lesion height (MLH), disease severity index (DSI) and harvested yield. Nine of the ten fungicides evaluated, and all fungicide timings that included an early bud application, resulted in disease reductions when compared to the non-treated 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.
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.

3.
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.

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.
Int J Obes (Lond) ; 30(1): 68-72, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16172618

RESUMO

OBJECTIVE: Endogenous peptide YY(3-36) (PYY(3-36)) is associated with postprandial regulation of appetite. We investigated the safety and effectiveness of peripherally administered synthetic human PYY(3-36) for 14 days in New Zealand white rabbits. Weight gain and food consumption were assessed and pharmacokinetics and toxicity characterized. RESEARCH METHODS AND PROCEDURES: In all, 24 animals were randomized to one of four intravenous treatment groups - control (0.9% saline) or PYY(3-36) bolus at 4.1, 41.0, or 205 microg/kg/day. Body weight and consumption of fixed food allotment were measured daily. Hematology and serum chemistries were profiled at baseline and Day 15, and pharmacokinetics measured following dose 14. Histopathologic examination of designated tissues and organs in control and PYY(3-36) 205 mug/kg animals was conducted. All animals were subject to clinical and macroscopic observation. RESULTS: The trend effect of higher dose PYY(3-36) on lower average weight was significant (P = 0.01; Day 14 compared to baseline) and its effect on reduced food consumption was suggested (P = 0.065; number of days < or =75% food eaten, compared with control). Hematology and clinical chemistries were within normal limits pretest and at Day 15. No clinical, macroscopic, histologic, or microscopic changes related to the test article were observed over the course of study. DISCUSSION: Lower average weight occurs in rabbits treated once daily with intravenous injection PYY(3-36) (205 microg/kg/day) over 14 days. No clinical or histologic signs of toxicity were observed. Further research is warranted to describe alternate routes of peripheral administration for optimizing weight control.


Assuntos
Depressores do Apetite/uso terapêutico , Peso Corporal , Obesidade/prevenção & controle , Peptídeo YY/uso terapêutico , Animais , Depressores do Apetite/farmacocinética , Depressores do Apetite/toxicidade , Regulação do Apetite , Peso Corporal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Infusões Intravenosas , Masculino , Obesidade/sangue , Fragmentos de Peptídeos , Peptídeo YY/sangue , Peptídeo YY/toxicidade , Coelhos , Resposta de Saciedade/efeitos dos fármacos , Aumento de Peso/efeitos dos fármacos
6.
Am J Physiol Cell Physiol ; 281(1): C195-206, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11401842

RESUMO

The nonsense codon suppression technique was used to incorporate o-nitrobenzyl cysteine or o-nitrobenzyl tyrosine (caged Cys or Tyr) into the 9' position of the M2 transmembrane segment of the gamma-subunit of the muscle nicotinic ACh receptor expressed in Xenopus oocytes. The caged amino acids replaced an endogenous Leu residue that has been implicated in channel gating. ACh-induced current increased substantially after ultraviolet (UV) irradiation to remove the caging group. This represents the first successful incorporation of caged Cys into a protein in vivo and the first incorporation of caged amino acids within a transmembrane segment of a membrane protein. The bulky nitrobenzyl group does not prevent the synthesis, assembly, or trafficking of the ACh receptor. When side chains were decaged using 1-ms UV light flashes, the channels with caged Cys or caged Tyr responded with strikingly different kinetics. The increase in current upon photolysis of caged Cys was too rapid for resolution by the voltage-clamp circuit [time constant (tau) <10 ms], whereas the increase in current upon photolysis of caged Tyr was dominated by a phase with tau approximately 500 ms. Apparently, the presence of a bulky o-nitrobenzyl Tyr residue distorts the receptor into an abnormal conformation. Upon release of the caging group, the receptor relaxes, with tau approximately 500 ms, into a conformation that allows the channel to open. Tyr at the 9' position of the gamma-subunit greatly increases the ability of ACh to block the channel by binding within the channel pore. This is manifested in two ways. 1) A "rebound," or increase in current, occurs upon removal of ACh from the bathing medium; and 2) at ACh concentrations >400 microM, inward currents are decreased through the mutated channel. The ability to incorporate caged amino acids into proteins should have widespread utility.


Assuntos
Cisteína/metabolismo , Receptores Nicotínicos/metabolismo , Tirosina/metabolismo , Animais , Membrana Celular/metabolismo , Códon sem Sentido/genética , Potenciais da Membrana/fisiologia , Camundongos , Técnicas de Sonda Molecular , Estrutura Molecular , Oócitos/fisiologia , Fotólise , Estrutura Terciária de Proteína , Receptores Nicotínicos/genética , Supressão Genética/genética , Xenopus laevis
7.
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
8.
Orthopade ; 29(7): 645-9, 2000 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-10986710

RESUMO

In this paper, we present a medical robot system dedicated to support the surgeon during challenging tasks within orthopedic interventions. The main goal of this work is to develop a system as technically simple as the surgical requirements allow to keep its cost and complexity to a minimum. Therefore, we primarily focus on calibrated X-ray imaging for image acquisition, an easy registration procedure and robotic execution using a positioning device with simple parallel kinematics. Examples of different orthopedic interventions using the compact robot system for image-guided orthopedic surgery (CRIGOS) are presented, as well as various modes of execution of the device.


Assuntos
Ortopedia , Robótica , Terapia Assistida por Computador , Artroplastia do Joelho , Humanos , Raios X
10.
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
11.
Monografia em Inglês | BINACIS | ID: bin-139408

RESUMO

El suministro de agua potable en Dinamarca se basa principalmente en la extraccion de aguas subterraneas. Para asegurar el suministro en el futuro, Dinamarca trabaja en tres politicas: la proteccion del agua subterranea contra la contaminacion, metodos alternativos de extraccion y tratamiento, y ahorro en el consumo. El articulo trata sobre las dos primeras y propone la recarga artificial del agua subterranea


Assuntos
Dinamarca , Abastecimento de Água , Água Subterrânea
12.
Monografia em Inglês | BINACIS | ID: bin-64903

RESUMO

El suministro de agua potable en Dinamarca se basa principalmente en la extraccion de aguas subterraneas. Para asegurar el suministro en el futuro, Dinamarca trabaja en tres politicas: la proteccion del agua subterranea contra la contaminacion, metodos alternativos de extraccion y tratamiento, y ahorro en el consumo. El articulo trata sobre las dos primeras y propone la recarga artificial del agua subterranea


Assuntos
Abastecimento de Água , Água Subterrânea
13.
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
15.
Clin Orthop Relat Res ; (338): 139-52, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9170375

RESUMO

Thrombophilia may cause thrombotic venous occlusion in the femoral head, with venous hypertension and hypoxic bone death, leading to Legg-Perthes disease. Resistance to activated protein C, the most common thrombophilic trait, was measured in 64 children with Legg-Perthes disease. Genomic deoxyribonucleic acid was studied to delineate the CGA-->CAA substitution at position 1691 of the Factor V Leiden gene responsible for resistance to activated protein C. The activated protein C ratio was calculated by dividing clotting time obtained with activated protein C-calcium chloride by clotting time obtained with calcium chloride alone. Resistance to activated protein C, with a low activated protein C ratio (less than 2.19, the 5th percentile for 160 normal pediatric controls) was the most common coagulation defect, found in 23 of 64 children with Legg-Perthes disease versus 7 of 160 pediatric controls. Eight of 64 children with Legg-Perthes disease had a low activated protein C ratio and the mutant Factor V gene (7 heterozygotes, 1 homozygote) versus 1 of 101 normal pediatric controls. Two or 3 generation vertical and horizontal transmission of heterozygosity for the mutant Factor V gene was found in 4 of the 8 kindreds. Of 64 children with Legg-Perthes disease, only 14 (22%) had entirely normal coagulation measures. Resistance to activated protein C appears to be a pathogenetic cause of Legg-Perthes disease.


Assuntos
Transtornos da Coagulação Sanguínea/fisiopatologia , Doença de Legg-Calve-Perthes/fisiopatologia , Proteína C/metabolismo , Transtornos da Coagulação Sanguínea/complicações , Transtornos da Coagulação Sanguínea/genética , Testes de Coagulação Sanguínea , Criança , Fator V/análise , Feminino , Heterozigoto , Homozigoto , Humanos , Doença de Legg-Calve-Perthes/etiologia , Doença de Legg-Calve-Perthes/genética , Masculino , Mutação , Linhagem
16.
Aktuelle Radiol ; 7(2): 104-11, 1997 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-9172662

RESUMO

Guidelines and standards supplementing the German "Röntgenverordnung" initiated a complex system of quality control in diagnostic radiology. Cost and profit are analysed for two hospitals of comparable size (Klinikum Buch and Klinikum Nürberg). The considerable expenses that must be incurred for measuring devices, equipment, working time and extra charges on the one hand, are the items that are opposed to achieving a higher image quality and dose reduction on the other. Public quality control enables to demonstrate the quality and to optimise imaging procedures in diagnostic radiology. A critical evaluation of the results of quality control suggests further developments. We should consider larger time intervals for quality tests in some cases, while focussing on techniques with high radiation exposure, e.g. computed tomography, where dose reductions are highly effective.


Assuntos
Garantia da Qualidade dos Cuidados de Saúde/legislação & jurisprudência , Radiografia/instrumentação , Adolescente , Criança , Análise Custo-Benefício , Feminino , Alemanha , Humanos , Lactente , Masculino , Garantia da Qualidade dos Cuidados de Saúde/economia , Doses de Radiação , Radiografia/economia
17.
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
18.
Chirality ; 9(1): 32-6, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9094201

RESUMO

A specific plasma level assay for the enantiomers of alpha-lipoic acid is described. It makes use of liquid-liquid extraction, chemical reduction to the dithiol enantiomers, and their precolumn chiral derivatisation with o-phthalaldehyde in the presence of D-phenylalanine. The two diastereomeric derivatives are separated by reversed-phase HPLC with fluorescence detection. The working range of the assay is between 15 ng/ml (lower limit of quantitation) and 1,000 ng/ml for either enantiomer.


Assuntos
Ácido Tióctico/sangue , Calibragem , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Padrões de Referência , Espectrometria de Fluorescência , Estereoisomerismo
19.
Aktuelle Radiol ; 7(6): 344-50, 1997 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-9467031

RESUMO

Relationships from benefits-costs analyses in radiography are presented. The impact of several factors (equipment, frequency of examinations, ...) on the planning of a department and special financial aspects, e.g., leasing of equipment, are discussed. The cost relationships of conventional versus digital radiography are demonstrated for the example of a 1000-bed hospital.


Assuntos
Intensificação de Imagem Radiográfica/economia , Radiografia/economia , Análise Custo-Benefício , Alemanha , Custos Hospitalares , Humanos , Tomografia Computadorizada por Raios X/economia
20.
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
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