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1.
Plant Dis ; 96(3): 454, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30727105

RESUMO

Early blight of potato (Solanum tuberosum) is caused by Alternaria solani and occurs annually to some degree in Idaho. The timing of its appearance and rate of disease progress determine the impact on the potato crop. Though losses rarely exceed 20%, they can be higher and occur in stored potatoes if the disease is not controlled. Early blight is managed mainly by cultural practices such as plant nutrition, water management, and avoidance of plant stress, but also with the use of foliar fungicides. Currently, the main fungicides labeled for control of early blight are in the carboxamide and strobilurin fungicide groups. Development of resistance to some fungicide groups may contribute to the loss of control of early blight. Isolates of A. solani from Idaho potatoes were tested for resistance to boscalid in the carboxamide group. Diseased potato leaves with early blight symptoms were collected from fields near Parma, Rupert, and Aberdeen in southern Idaho in 2009 and 2010 and Bonners Ferry in northern Idaho in 2010. To obtain A. solani isolates from leaves, small pieces of leaf tissue (5 × 5 mm) were taken from the center of early blight lesions and streaked across the surface of a thin layer (3 mm) of water agar. Plates were incubated at 25°C overnight to allow spores to germinate. Single germinated A. solani spores were transferred to acidified potato dextrose agar and incubated in the dark at 25°C. Germinated spores were identified based on spore morphology. Spores of A. solani can be easily distinguished from other Alternaria spp. found on potato because they are ellipsoid to oblong and taper to a long beak that is usually as long as the spore body. The identity of cultures grown from single spores was confirmed by colony and spore morphology. Sensitivity of A. solani isolates to boscalid was determined by the spiral gradient endpoint method (2). For all isolates, the effective concentration for 50% reduction in growth was outside the range of the spiral plate dilution series (i.e., isolates were either completely insensitive or completely sensitive to boscalid). In total, 46 isolates (20 collected in 2009 and 26 collected in 2010) were tested against boscalid. Experiments were carried out twice with 2009 isolates using mycelial strips and conidial suspensions. Experiments with 2010 isolates were carried out three times using only conidial suspensions. Of the isolates from 2009, 15% were insensitive. There was no difference between the use of mycelial strips or conidial suspensions. In 2010, 62% of isolates were insensitive. By location, 72% of isolates from Parma, 73% from Rupert, 63% from Aberdeen, and 44% from Bonners Ferry were insensitive. Resistance to boscalid has been reported in A. alternata isolates from pistachio (1,3). However, to our knowledge, this is the first report of resistance to boscalid in isolates of A. solani on potato. These data suggest that resistance to boscalid is widespread in Idaho, even in areas like Bonners Ferry where potato cultivation is limited. Boscalid insensitivity in vitro may not translate directly to commercial production and currently there is no evidence to suggest that boscalid has failed to control early blight in Idaho. However, the discovery of insensitive isolates suggests that boscalid should be considered at high risk of resistance development. References: (1) H. Avenot et al. Plant Dis. 91:1345, 2007. (2) H. Förster et al. Phytopathology 94:163, 2004. (3) N. Rosenzweig et al. (Abstr.) Phytopathology 93(suppl.):S75, 2003.

2.
Plant Dis ; 96(3): 460, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30727112

RESUMO

Rhizoctonia solani is an important pathogen of potato (Solanum tuberosum) causing qualitative and quantitative losses. It has been associated with black scurf and stem canker. Isolates of the fungus are assigned to one of 13 known anastomosis groups (AGs), of which AG3 is most commonly associated with potato disease (2,4). In August 2011, diseased potato plants originating from Rupert, ID (cv. Western Russet) and Three Rivers, MI (cv. Russet Norkotah) were received for diagnosis. Both samples displayed stem and stolon lesions typically associated with Rhizoctonia stem canker. The presence of R. solani was confirmed through isolation as previously described (4) and the Idaho and Michigan isolates were designated J11 and J8, respectively. AG was determined by sequencing the rDNA internal transcribed spacer (ITS) region using primers ITS5 and ITS4 (3). The resulting sequences of the rDNA ITS region of isolates J8 and J11 (GenBank Accession Nos. HE608839 and HE608840, respectively) were between 97 and 100% identical to that of other AG2-2IIIB isolates present in sequence databases (GenBank Accession Nos. FJ492075 and FJ492170, respectively). Koch's postulates were confirmed for each isolate by carrying out the following protocol. Each isolate was cultured on potato dextrose agar for 14 days. Five 10-mm agar plugs were then placed on top of seed tubers (cv. Maris Piper) in 1-liter pots containing John Innes Number 3 compost (John Innes Manufacturers Association, Reading, UK). Pots were held in a controlled environment room at 18°C with 50% relative humidity and watered as required. After 21 days, plants were removed and assessed for disease. Typical Rhizoctonia stem lesions were observed and R. solani was successfully reisolated from symptomatic material. To our knowledge, this is the first report of AG2-2IIIB causing disease on potatoes in the United States. In the United States, AGs 2-1, 3, 4, 5, and 9 have all been previously implicated in Rhizoctonia potato disease (2). AG2-2IIIB should now also be considered a potato pathogen in the United States. Knowledge of which AG is present is invaluable when considering a disease management strategy. AG2-2IIIB is a causal agent of sugar beet (Beta vulgaris) root rot in Idaho (1). Sugar beet is commonly grown in crop rotation with potato and such a rotation could increase the risk of soilborne infection to either crop by AG2-2IIIB. References: (1) C. A. Strausbaugh et al. Can. J. Plant Pathol. 33:210, 2011. (2) L. Tsror. J. Phytopatol. 158:649, 2010. (3) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, Inc., New York, 1990. (4) J. W.Woodhall et al. Plant Pathol. 56:286, 2007.

3.
Science ; 228(4696): 175-7, 1985 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-3975636

RESUMO

Computerized pattern recognition techniques can be applied to the study of complex chemical communication systems. Analysis of high resolution gas chromatographic concentration patterns of the major volatile components of the scent marks of a South American primate, Saguinus fuscicollis, demonstrates that the concentration patterns can be used to predict the gender and subspecies of unknown donors.


Assuntos
Computadores , Reconhecimento Automatizado de Padrão , Feromônios/fisiologia , Atrativos Sexuais/fisiologia , Animais , Fenômenos Químicos , Química , Cromatografia Gasosa , Feminino , Masculino , Saguinus/fisiologia , Glândulas Odoríferas/fisiologia , Relação Estrutura-Atividade
4.
Nanotechnology ; 20(43): 434003, 2009 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-19801750

RESUMO

In this paper, we present a detailed investigation into the suitability of atomic force microscopy (AFM) cantilevers with integrated deflection sensor and micro-actuator for imaging of soft biological samples in fluid. The Si cantilevers are actuated using a micro-heater at the bottom end of the cantilever. Sensing is achieved through p-doped resistors connected in a Wheatstone bridge. We investigated the influence of the water on the cantilever dynamics, the actuation and the sensing mechanisms, as well as the crosstalk between sensing and actuation. Successful imaging of yeast cells in water using the integrated sensor and actuator shows the potential of the combination of this actuation and sensing method. This constitutes a major step towards the automation and miniaturization required to establish AFM in routine biomedical diagnostics and in vivo applications.


Assuntos
Técnicas Biossensoriais/métodos , Microscopia de Força Atômica/instrumentação , Microscopia de Força Atômica/métodos , Saccharomyces cerevisiae/ultraestrutura , Ar , Reagentes de Ligações Cruzadas , Desenho de Equipamento , Água
5.
Nat Commun ; 10(1): 889, 2019 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-30792498

RESUMO

The biological carbon pump drives a flux of particulate organic carbon (POC) through the ocean and affects atmospheric levels of carbon dioxide. Short term, episodic flux events are hard to capture with current observational techniques and may thus be underrepresented in POC flux estimates. We model the potential hidden flux of POC originating from Antarctic krill, whose swarming behaviour could result in a major conduit of carbon to depth through their rapid exploitation of phytoplankton blooms and bulk egestion of rapidly sinking faecal pellets (FPs). Our model results suggest a seasonal krill FP export flux of 0.039 GT C across the Southern Ocean marginal ice zone, corresponding to 17-61% (mean 35%) of current satellite-derived export estimates for this zone. The magnitude of our conservatively estimated flux highlights the important role of large, swarming macrozooplankton in POC export and, the need to incorporate such processes more mechanistically to improve model projections.


Assuntos
Euphausiacea/metabolismo , Animais , Regiões Antárticas , Carbono/metabolismo , Ciclo do Carbono , Metabolismo Energético , Fezes/química , Gelo , Modelos Biológicos , Água do Mar , Zooplâncton/metabolismo
6.
Nat Commun ; 10(1): 5340, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31745095

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

7.
Nat Commun ; 10(1): 4742, 2019 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-31628346

RESUMO

Antarctic krill (Euphausia superba) are swarming, oceanic crustaceans, up to two inches long, and best known as prey for whales and penguins - but they have another important role. With their large size, high biomass and daily vertical migrations they transport and transform essential nutrients, stimulate primary productivity and influence the carbon sink. Antarctic krill are also fished by the Southern Ocean's largest fishery. Yet how krill fishing impacts nutrient fertilisation and the carbon sink in the Southern Ocean is poorly understood. Our synthesis shows fishery management should consider the influential biogeochemical role of both adult and larval Antarctic krill.


Assuntos
Biomassa , Euphausiacea/fisiologia , Cadeia Alimentar , Spheniscidae/fisiologia , Baleias/fisiologia , Animais , Regiões Antárticas , Carbono/metabolismo , Ciclo do Carbono , Euphausiacea/crescimento & desenvolvimento , Água do Mar/química
8.
Polar Biol ; 40(10): 2001-2013, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-32009725

RESUMO

Antarctic krill (Euphausia superba) play a central role in the food web of the Southern Ocean, forming a link between primary production and large predators. Krill produce large, faecal pellets (FP) which can form a large component of mesopelagic particulate organic carbon (POC) fluxes. However, the patchy distribution of krill swarms, highly variable pellet composition, and variable sinking and attenuation rates means that these episodic, but potentially large, carbon fluxes are difficult to sample or model. We measured particle flux and type using Marine Snow Catchers (MSC) in the marginal ice zone near the South Orkneys, Antarctica. Krill FP were the dominant component of the POC flux in the upper 200 m (typically 60-85%). FP sinking velocities measured onboard were highly variable (15-507 m d-1) but overall high, with mean equivalent velocities of 172, 267, and 161 m d-1 at our three stations. The high numbers of krill FP sinking through the mesopelagic suggest that krill FP can be transferred efficiently and/or that rates of krill FP production are high. We compared our direct MSC-derived estimates of krill FP POC flux (33-154 mg C m-2 d-1) and attenuation to estimates of krill FP production based on previous measurements of krill density and literature FP egestion rates, and estimated net krill FP attenuation rates in the upper mesopelagic. Calculated attenuation rates are sensitive to krill densities in the overlying water column but suggest that krill FP could be transferred efficiently through the upper mesopelagic, and, in agreement with our MSC attenuation estimates, could make large contributions to bathypelagic POC fluxes. Our study contrasts with some others which suggest rapid FP attenuation, highlighting the need for further work to constrain attenuation rates and assess how important the contribution of Antarctic krill FP could be to the Southern Ocean biological carbon pump.

9.
Drug Alcohol Depend ; 159: 181-9, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26775284

RESUMO

BACKGROUND: Methamphetamine abuse is linked with brain abnormalities, but its peripheral effects constitute an integral aspect of long-term methamphetamine use. METHODS: Eight male rhesus monkeys with long histories of intravenous methamphetamine self-administration were evaluated 1 day, and 1, 4, 12, 26, and 52 weeks after their last methamphetamine self-administration session. On test days, isoflurane-anesthetized animals received a 0.35 mg/kg IV methamphetamine challenge. A control group consisted of 10 age and gender matched drug naïve monkeys. Cardiovascular responses to methamphetamine were followed for 2.5h. Echocardiograms were acquired at 3 and 12 months of abstinence and in the control animals. RESULTS: No pre-methamphetamine baseline differences existed among 7 physiological measures across all conditions and controls. As expected, methamphetamine increased heart rate and blood pressure in controls. However, immediately following the self-administration period, the blood pressure response to methamphetamine challenge was reduced when compared to control monkeys. The peak and 150-min average heart rate increases, as well as peak blood pressure increases following methamphetamine were significantly elevated between weeks 12 to 26 of abstinence. These data indicate the development of tolerance followed by sensitization to methamphetamine cardiovascular effects. Echocardiography demonstrated decreased left ventricular ejection fraction and cardiac output at 3 months of abstinence. Importantly, both cardiovascular sensitization and cardiotoxicity appeared to be reversible as they returned toward control group levels after 1 year of abstinence. CONCLUSIONS: Enhanced cardiovascular effects may occur after prolonged abstinence in addicts relapsing to methamphetamine and may underlie clinically reported acute cardiotoxic events.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Débito Cardíaco/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Metanfetamina/administração & dosagem , Metanfetamina/farmacologia , Função Ventricular Esquerda/efeitos dos fármacos , Animais , Estudos de Casos e Controles , Tolerância a Medicamentos , Ecocardiografia , Macaca mulatta , Masculino , Metanfetamina/sangue , Autoadministração , Fatores de Tempo
10.
Oncology (Williston Park) ; 4(5): 197-9; discussion 207-8, 1990 May.
Artigo em Inglês | MEDLINE | ID: mdl-2143403

RESUMO

The evolution of cancer care from a focus on length of survival to quality of life is presented as a frame-work for the nurse's evolving role in the domain. Nurses have roles as clinicians, managers, researchers, teachers, and change agent/consultants and as such their impact on the specific factors affecting the quality of life of persons with cancer can be substantial. Patients are unique in their response to cancer and its treatment, as well as in their perspective as to what constitutes quality of life. The nurse's interventions must reflect and incorporate this uniqueness so that patients can be helped to live their lives fully and as they wish.


Assuntos
Neoplasias/enfermagem , Relações Enfermeiro-Paciente , Qualidade de Vida , Humanos , Neoplasias/terapia , Enfermagem Oncológica
11.
Am J Primatol ; 23(2): 87-98, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-31952410

RESUMO

Hydrolysis, extraction, and radioimmunoassay techniques for the estimation of excreted testosterone metabolites in the urine of saddle-back tamarins have been validated and are described. The steroids measured with the testosterone antiserum used are mostly present as glucuronides and sulfates. Immunoreactivity in high-performance liquid chromatography (HPLC) fractions of urinary extracts and in a standard mixture of cortisol, testosterone, and dihydrotestosterone (DHT) were compared. The fractions with the same retention data as testosterone accounted for the major part of the immunoreactivity. Several other immunoreactive compounds of unknown identity were present in low concentrations. These results suggest that testosterone conjugates are the major steroid metabolites measured with this method in Saguinus fuscicollis. Urinary testosterone levels of castrated males were much lower than those of intact males. Testosterone treatment of castrated males resulted in a temporary superphysiological increase in the levels of urinary testosterone and in an individually variable increase in the levels of the minor immunoreactive compounds. These results suggest that estimation of testosterone metabolite levels in urine is a valid method for the assessment of testicular activity in Saguinus fuscicollis.

12.
Am J Crit Care ; 10(4): 252-9, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11432213

RESUMO

BACKGROUND: Little is known about the acute pain experiences of traumatically injured critically ill patients. OBJECTIVES: To describe pain experiences of traumatically injured adults during the first 72 hours of hospitalization. METHODS: Thirty multiply injured adults at a level I trauma center participated in the study. Pain was measured by using the McGill Pain Questionnaire and a visual analog scale. Subjects completed pain measures while at rest in a supine recumbent position and after a turn onto the side. RESULTS: The typical subject was 37 years old, had 4 major blunt trauma injuries, and had received the equivalent of 55.9 mg of morphine during the 24 hours before data collection. Mean at-rest scores were 26.5 on the pain-rating index, 2 on the present pain intensity index, and 34.6 on the visual analog scale. Immediately after the turn, mean scores on the visual analog scale increased from 25 to 48.1 (P = .002). Other pain scores after the turn did not differ significantly from at-rest values. Subjects who turned had lower scores on the visual analog scale at rest (P = .02) and less anxiety (P = .02) than did those who refused to turn. Ninety-six percent reported pain in the injured areas, and 36% reported pain related to biomedical devices. No relationship was found among reported pain and demographic, treatment, or clinical variables. CONCLUSIONS: Additional research is needed on pain at rest and during commonly performed procedures and on improved methods for pain relief in traumatically injured critically ill patients.


Assuntos
Cuidados Críticos/métodos , Medição da Dor/estatística & dados numéricos , Dor/psicologia , Percepção , Ferimentos e Lesões/complicações , Centros Médicos Acadêmicos , Adolescente , Adulto , Baltimore , Feminino , Humanos , Masculino , Dor/classificação , Dor/tratamento farmacológico , Dor/etiologia , Inquéritos e Questionários , Centros de Traumatologia , Ferimentos e Lesões/enfermagem
13.
Oncol Nurs Forum ; 22(8 Suppl): 19-24, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8524674

RESUMO

PURPOSE/OBJECTIVES: To review the education of the advanced practice nurse (APN) with a focus on curriculum and issues related to the oncology specialization. DATA SOURCES: The State-of-the-Knowledge Conference on Advanced Practice in Oncology Nursing, journal articles, monographs, and authors' personal experiences. DATA SYNTHESIS: APN education is a current issue in nursing, as well as in the specialty of oncology nursing. Current trends in the delivery of health care require reform of graduate education in nursing to better prepare APNs to shape and respond to the healthcare needs of the public along the entire cancer care continuum. CONCLUSIONS: APN education remains a dynamic, ever-evolving enterprise. The Oncology Nursing Society (ONS) and the American Cancer Society (ACS) have taken a proactive stand on APN education by revising master's curriculum guidelines and supporting the conference. IMPLICATIONS FOR NURSING PRACTICE: APN education in oncology will be an ongoing area of exploration for both ONS and ACS, as well as for leaders in oncology nursing. Development of graduate, postgraduate, and continuing education programs at the APN level of expertise will support high-quality advanced practice in oncology nursing. The feedback mechanisms among practice, education, and research will provide educational programs that will make a difference in the care of patients with cancer.


Assuntos
Enfermeiros Clínicos/educação , Profissionais de Enfermagem/educação , Enfermagem Oncológica/educação , American Cancer Society , Currículo , Educação Continuada em Enfermagem/organização & administração , Educação de Pós-Graduação em Enfermagem/organização & administração , Humanos , Sociedades de Enfermagem , Estados Unidos
14.
Nurse Educ ; 16(4): 30-5, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1866094

RESUMO

This study was conducted to establish the reliability and validity of the Dunn, Dunn, and Price Productivity Environmental Preferences Survey (PEPS) with baccalaureate nursing students and to identify differences between subpopulations (age, class level, sex, type of student (RN versus generic] and students at risk. The findings have implications for nurse educators who choose teaching-learning experiences for a diverse student population.


Assuntos
Comportamento de Escolha , Aprendizagem , Estudantes de Enfermagem/psicologia , Inquéritos e Questionários/normas , Adolescente , Adulto , Atitude , Bacharelado em Enfermagem , Eficiência , Feminino , Humanos , Masculino , Modelos Psicológicos , Reprodutibilidade dos Testes , Ensino/métodos , Ensino/normas
15.
Ostomy Wound Manage ; 44(4): 76-8, 80, 82 passim, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9611608

RESUMO

Mentoring plays a significant role in business, industry, government, education, and healthcare. Mentoring relationships help promote the individual's professional growth and development. Such development involves knowledge and skill acquisition, which is facilitated by interaction with other, more experienced and proficient professionals. The Belcher-Sibbald Continuum of Learning describes the relationship among the concepts of role modeling, networking, preceptoring, and mentoring. Each concept is defined and described as a unique relationship which promotes professional growth and development. In addition, three mentoring/networking relationships in the context of the wound care community are presented to provide insight into this type of relationship.


Assuntos
Relações Interprofissionais , Mentores/psicologia , Estomia/enfermagem , Especialidades de Enfermagem/educação , Humanos , Modelos Educacionais , Papel (figurativo)
16.
Clin Nurse Spec ; 3(2): 60-5, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2736459

RESUMO

Although nurse researchers have generated research findings, practitioners in clinical practice have not consistently utilized them. Evaluation and modification of clinical practice through research is a key component of the role of the clinical nurse specialist (CNS). In this paper, an innovative model is described in which the Clinical Nurse Specialist coordinates specialty-based clinical research through the use of unit-based research forums, an outgrowth of unit-based quality assurance. Such a model allows staff at the unit level to engage in problem-solving dialogues, resulting in increased use of research findings and generation of original research.


Assuntos
Pesquisa em Enfermagem Clínica , Enfermeiros Clínicos , Pesquisa em Enfermagem , Prática Profissional , Protocolos Clínicos , Comunicação , Humanos , Liderança , Cuidados de Enfermagem , Resolução de Problemas , Garantia da Qualidade dos Cuidados de Saúde
17.
Med Phys ; 39(6Part8): 3688-3689, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28518910

RESUMO

PURPOSE: Real-time sub-millimeter head motion compensation during frameless SRS delivery has the potential to achieve the accuracy of frame-based SRS while being significantly less invasive. Previously, we demonstrated real-time 6D head motion monitoring using an optical camera, however, at the time we were limited to only 3D (x-y-z) of head motion correction due to mechanical restrictions of the head platform. In this work we investigate the feasibility of using a compact 6D robotic Stewart platform (hexapod) placed under the patient's head to perform both translational and rotational motion compensation in real-time. Benefits of a hexapod approach over a conventional serial kinematics stage include less flex, compactness, high force to weight ratio, and fast response times. METHODS: A hexapod is a parallel robotics device consisting of two platforms connected by six linear actuators oriented at particular angles. To provide accurate motion in 6D, the desired position of the top platform (head) was ascertained using inverse kinematics. MATLAB was used to simulate the six actuator positions for performing motion along x-y-z-phi -theta-psi. Prior recorded 6D human volunteer head motion data was used as an input for simulation of motion compensation. Six Firgelli L12-P linearservo actuators, together with a PCI-7344 motion controller and Labview software, were used for initial construction of a hexapod prototype. RESULTS: The necessary actuator lengths over time were computed for this data, simulating the required 6D movement of the hexapod for motion correction. Simulations on previously collected volunteer data indicate a hexapod system is capable of responding to subject head motion with corrections of precise movements, and solutions to the linear system can be computed at near real-time speeds. CONCLUSIONS: Based on simulated results, it was successfully demonstrated that a hexapod device can compensate for small patient head motions along all six degrees of freedom.

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