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1.
Nature ; 565(7738): 209-212, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30602792

RESUMEN

The Einstein-de Haas effect was originally observed in a landmark experiment1 demonstrating that the angular momentum associated with aligned electron spins in a ferromagnet can be converted to mechanical angular momentum by reversing the direction of magnetization using an external magnetic field. A related problem concerns the timescale of this angular momentum transfer. Experiments have established that intense photoexcitation in several metallic ferromagnets leads to a drop in magnetization on a timescale shorter than 100 femtoseconds-a phenomenon called ultrafast demagnetization2-4. Although the microscopic mechanism for this process has been hotly debated, the key question of where the angular momentum goes on these femtosecond timescales remains unanswered. Here we use femtosecond time-resolved X-ray diffraction to show that most of the angular momentum lost from the spin system upon laser-induced demagnetization of ferromagnetic iron is transferred to the lattice on sub-picosecond timescales, launching a transverse strain wave that propagates from the surface into the bulk. By fitting a simple model of the X-ray data to simulations and optical data, we estimate that the angular momentum transfer occurs on a timescale of 200 femtoseconds and corresponds to 80 per cent of the angular momentum that is lost from the spin system. Our results show that interaction with the lattice has an essential role in the process of ultrafast demagnetization in this system.

2.
Learn Behav ; 49(1): 36-53, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33532988

RESUMEN

Animal cooperation in the wild often involves multiple individuals that must tolerate each other in close proximity. However, most cooperation experiments in the lab are done with two animals, that are often also physically separated. Such experiments are useful for answering some pertinent questions, for example about the understanding of the role of the partner and strategies of partner control, but say little about factors determining successful cooperation with multiple partners in group settings. We explored the influence of dominance, rank distance, tolerance, affiliation, and coordination by testing kea parrots with a box requiring two, three, or four chains to be pulled simultaneously to access food rewards. The reward could be divided unevenly, but not monopolized completely. Eventually dyadic, triadic, and tetradic cooperation tasks were solved, showing that non-human animals are capable of tetradic cooperation in an experimental setup. Starting with two chains, we found that in a dyad monopolization of the box by the highest-ranking bird was the largest obstacle preventing successful cooperation. High-ranking birds learned to restrain themselves from monopolizing the box during a single session in which monopolization was hindered by the presence of a large number of birds. Thereafter, restraint by dominants remained the strongest factor determining success in the first trial in dyadic, triadic, and tetradic setups. The probability of success increased with the degree of restraint shown by all dominant subjects present. Previous experience with the task contributed to success in subsequent sessions, while increasing rank distance reduced success notably in the four-chain setup.


Asunto(s)
Loros , Animales , Comprensión , Alimentos , Aprendizaje , Recompensa
3.
Women Health ; 61(1): 15-26, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33256565

RESUMEN

Antenatal care (ANC) can improve maternal health. We examined associations of individual and community socioeconomic status (SES) with the quality of ANC in West and Central Africa. Data were from the 2009-2011 UNICEF Multiple Indicator Cluster Surveys for women in seven countries (n = 24,718). Individual SES variables included women's education and wealth; community SES was defined as low or high poverty index. ANC quality was defined as receiving six services: blood pressure monitoring, blood tests, urine tests, malaria prophylaxis, tetanus vaccine, and HIV screening, and coded low or high. We used multilevel logistic regression to estimate fixed and random effects of individual and community SES on ANC quality. Less than one-fourth of women received high-quality ANC. Only small percentages of women had malaria prophylaxis and were counseled and tested for HIV. In adjusted country-stratified results, living in a poor community was associated with reduced odds of receiving high-quality ANC in six countries (Central African Republic: odds ratio, OR = 0.76; 95% confidence interval, CI:0.58-0.98; Chad: OR = 0.48; CI:0.32-0.74; Ghana: OR = 0.86; CI:0.61-0.97; Nigeria: OR = 0.74; CI:0.61-0.92; Sierra Leone: OR = 0.71; CI:0.57-0.91; and Togo: OR = 0.80; CI:0.47-0.91). The health system may be missing important opportunities to provide high-quality ANC and, thereby, improve pregnancy outcomes in these settings.


Asunto(s)
Servicios de Salud Materna/estadística & datos numéricos , Pobreza , Atención Prenatal/estadística & datos numéricos , Calidad de la Atención de Salud , Adolescente , Adulto , Femenino , Ghana , Humanos , Salud Materna , Análisis Multinivel , Nigeria , Aceptación de la Atención de Salud/estadística & datos numéricos , Embarazo , Factores Socioeconómicos , Adulto Joven
4.
HNO ; 68(12): 935-943, 2020 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-32617608

RESUMEN

Necrotizing fasciitis (NF) is a life-threatening, usually bacterial, soft tissue infection that rarely affects the head and neck region. Rapid progression and systemic illness are typical for the disease and complicate diagnosis. Immediate surgical and antimicrobial therapy is required. Three cases of cervicofacial NF are presented in this case report. All patients showed a rapidly progressing, painful swelling and redness in the cervicofacial region. After diagnosing NF based on clinical symptoms, laboratory parameters, and CT, the patients were treated with systemic antibiotics and multiple extensive debridements. Two of the three patients died within 48 h from systemic illness with septic organ failure; one patient was discharged after intensive care treatment and reconstruction of the tissue defects caused by debridement. NF is a fast-developing soft tissue infection associated with high mortality and morbidity, and is often recognized too late. Diagnosis is based on clinical signs such as progressive diffuse swelling, pain, erythema, and early systemic illness. Laboratory parameters (Laboratory Risk Indicator for Necrotizing Fasciitis [LRINEC] score) and imaging via CT or MRT are helpful. CT/MRT images can show soft tissue swelling with pathognomonic gas formation. Immediate surgical debridement and antimicrobial therapy are critical for survival. Intravenously administered immunoglobulins and hyperbaric pressure therapy should only be used as supplementary treatments.


Asunto(s)
Fascitis Necrotizante , Antibacterianos/uso terapéutico , Desbridamiento , Fascitis Necrotizante/tratamiento farmacológico , Fascitis Necrotizante/terapia , Humanos , Dolor , Factores de Riesgo
5.
Opt Express ; 27(8): 10854-10865, 2019 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-31052939

RESUMEN

Using reflective cross-polarized 2D THz time-domain spectroscopy in the range of 1-12 THz, we follow the trajectory of the out-of-equilibrium electron population in the low-bandgap semiconductor InSb. The 2D THz spectra show a set of distinct features at combinations of the plasma-edge and vibration frequencies. Using finite difference time domain simulations combined with a tight binding model of the band structure, we assign these features to electronic nonlinearities and show that the nonlinear response in the first picoseconds is dominated by coherent ballistic motion of the electrons. We demonstrate that this technique can be used to investigate the landscape of the band curvature near the Γ-point, as illustrated by the observation of anisotropy in the (100)-plane.

6.
Eur J Neurol ; 26(2): 333-341, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30308696

RESUMEN

BACKGROUND AND PURPOSE: Early pharmacological deep vein thrombosis (DVT) prophylaxis is recommended by guidelines, but rarely started within 48 h. We aimed to analyze the effect of early (within 48 h) versus late (>48 h) DVT prophylaxis on hematoma expansion (HE) and outcome in patients with spontaneous intracerebral hemorrhage (ICH). METHODS: We analyzed 134 consecutive patients admitted to a tertiary neurointensive care unit with diagnosed spontaneous ICH, without previous anticoagulation, severe coagulopathy, hematoma evacuation, early withdrawal of therapy or ineligibility for DVT prophylaxis according to our institutional protocol. Significant late HE was defined as ≥6 mL increase of hematoma volume between neuroimaging within 48 h and day 3-6. Multivariate analysis was performed to identify risk factors for late HE, poor 3-month outcome (modified Rankin Scale score ≥ 4) and mortality. RESULTS: Patients had a median Glasgow Coma Scale score of 14 [interquartile range (IQR), 10-15], ICH volume of 11 (IQR, 5-24) mL and were 71 (IQR, 61-76) years old. A total of 56% (n = 76) received early DVT prophylaxis, 37% (n = 50) received late DVT prophylaxis and 8 (6%) had unknown bleeding onset. Patients with early DVT prophylaxis had smaller ICH volume [9.5 (IQR, 4-18.5) vs. 17.5 (IQR, 8-29) mL, P = 0.038] and were more often comatose (26% vs. 10%, P = 0.025). Significant late HE [n = 5/134 (3.7%)] was associated with larger initial ICH volume (P = 0.02) and lower thrombocyte count (P = 0.03) but not with early DVT prophylaxis (P = 0.36). Early DVT prophylaxis was not associated with worse outcome. CONCLUSION: Significant late HE is uncommon and DVT prophylaxis within 48 h of symptom onset may be safe in selected patients with ICH.


Asunto(s)
Anticoagulantes/uso terapéutico , Hemorragia Cerebral/complicaciones , Enoxaparina/uso terapéutico , Hematoma/etiología , Trombosis de la Vena/prevención & control , Anciano , Anticoagulantes/efectos adversos , Enoxaparina/efectos adversos , Femenino , Escala de Coma de Glasgow , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Terapia Trombolítica/efectos adversos , Trombosis de la Vena/tratamiento farmacológico
7.
Ann Bot ; 121(7): 1299-1308, 2018 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-29579151

RESUMEN

Background and Aims: Growing cultivars differing by their disease resistance level together (cultivar mixtures) can reduce the propagation of diseases. Although architectural characteristics of cultivars are little considered in mixture design, they could have an effect on disease, in particular through spore dispersal by rain splash, which occurs over short distances. The objective of this work was to assess the impact of plant height of wheat cultivars in mixtures on splash dispersal of Zymoseptoria tritici, which causes septoria tritici leaf blotch. Methods: We used a modelling approach involving an explicit description of canopy architecture and splash dispersal processes. The dispersal model computed raindrop interception by a virtual canopy as well as the production, transport and interception of splash droplets carrying inoculum. We designed 3-D virtual canopies composed of susceptible and resistant plants, according to field measurements at the flowering stage. In numerical experiments, we tested different heights of virtual cultivars making up binary mixtures to assess the influence of this architectural trait on dispersal patterns of spore-carrying droplets. Key Results: Inoculum interception decreased exponentially with the height relative to the main inoculum source (lower diseased leaves of susceptible plants), and little inoculum was intercepted further than 40 cm above the inoculum source. Consequently, tall plants intercepted less inoculum than smaller ones. Plants with twice the standard height intercepted 33 % less inoculum than standard height plants. In cases when the height of suscpeptible plants was doubled, inoculum interception by resistant leaves was 40 % higher. This physical barrier to spore-carrying droplet trajectories reduced inoculum interception by tall susceptible plants and was modulated by plant height differences between cultivars of a binary mixture. Conclusions: These results suggest that mixture effects on spore dispersal could be modulated by an adequate choice of architectural characteristics of cultivars. In particular, even small differences in plant height could reduce spore dispersal.


Asunto(s)
Resistencia a la Enfermedad , Enfermedades de las Plantas/prevención & control , Triticum/anatomía & histología , Ascomicetos , Flores/anatomía & histología , Imagenología Tridimensional , Enfermedades de las Plantas/etiología , Hojas de la Planta/anatomía & histología , Lluvia , Esporas Fúngicas , Triticum/inmunología , Triticum/fisiología
8.
Nat Mater ; 15(6): 601-5, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27159018

RESUMEN

Measuring how the magnetic correlations evolve in doped Mott insulators has greatly improved our understanding of the pseudogap, non-Fermi liquids and high-temperature superconductivity. Recently, photo-excitation has been used to induce similarly exotic states transiently. However, the lack of available probes of magnetic correlations in the time domain hinders our understanding of these photo-induced states and how they could be controlled. Here, we implement magnetic resonant inelastic X-ray scattering at a free-electron laser to directly determine the magnetic dynamics after photo-doping the Mott insulator Sr2IrO4. We find that the non-equilibrium state, 2 ps after the excitation, exhibits strongly suppressed long-range magnetic order, but hosts photo-carriers that induce strong, non-thermal magnetic correlations. These two-dimensional (2D) in-plane Néel correlations recover within a few picoseconds, whereas the three-dimensional (3D) long-range magnetic order restores on a fluence-dependent timescale of a few hundred picoseconds. The marked difference in these two timescales implies that the dimensionality of magnetic correlations is vital for our understanding of ultrafast magnetic dynamics.


Asunto(s)
Iridio/química , Campos Magnéticos , Simulación de Dinámica Molecular , Estroncio/química , Superconductividad
9.
Phys Rev Lett ; 118(24): 247401, 2017 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-28665649

RESUMEN

Femtosecond time-resolved x-ray diffraction is used to study a photoinduced phase transition between two charge density wave (CDW) states in 1T-TaS_{2}, namely the nearly commensurate (NC) and the incommensurate (I) CDW states. Structural modulations associated with the NC-CDW order are found to disappear within 400 fs. The photoinduced I-CDW phase then develops through a nucleation and growth process which ends 100 ps after laser excitation. We demonstrate that the newly formed I-CDW phase is fragmented into several nanometric domains that are growing through a coarsening process. The coarsening dynamics is found to follow the universal Lifshitz-Allen-Cahn growth law, which describes the ordering kinetics in systems exhibiting a nonconservative order parameter.

10.
Phytopathology ; 107(10): 1109-1122, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28643581

RESUMEN

Scenario analysis constitutes a useful approach to synthesize knowledge and derive hypotheses in the case of complex systems that are documented with mainly qualitative or very diverse information. In this article, a framework for scenario analysis is designed and then, applied to global wheat health within a timeframe from today to 2050. Scenario analysis entails the choice of settings, the definition of scenarios of change, and the analysis of outcomes of these scenarios in the chosen settings. Three idealized agrosystems, representing a large fraction of the global diversity of wheat-based agrosystems, are considered, which represent the settings of the analysis. Several components of global changes are considered in their consequences on global wheat health: climate change and climate variability, nitrogen fertilizer use, tillage, crop rotation, pesticide use, and the deployment of host plant resistances. Each idealized agrosystem is associated with a scenario of change that considers first, a production situation and its dynamics, and second, the impacts of the evolving production situation on the evolution of crop health. Crop health is represented by six functional groups of wheat pathogens: the pathogens associated with Fusarium head blight; biotrophic fungi, Septoria-like fungi, necrotrophic fungi, soilborne pathogens, and insect-transmitted viruses. The analysis of scenario outcomes is conducted along a risk-analytical pattern, which involves risk probabilities represented by categorized probability levels of disease epidemics, and risk magnitudes represented by categorized levels of crop losses resulting from these levels of epidemics within each production situation. The results from this scenario analysis suggest an overall increase of risk probabilities and magnitudes in the three idealized agrosystems. Changes in risk probability or magnitude however vary with the agrosystem and the functional groups of pathogens. We discuss the effects of global changes on the six functional groups, in terms of their epidemiology and of the crop losses they cause. Scenario analysis enables qualitative analysis of complex systems, such as plant pathosystems that are evolving in response to global changes, including climate change and technology shifts. It also provides a useful framework for quantitative simulation modeling analysis for plant disease epidemiology.


Asunto(s)
Hongos/fisiología , Modelos Teóricos , Enfermedades de las Plantas/prevención & control , Triticum/microbiología , Cambio Climático , Simulación por Computador , Productos Agrícolas , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/estadística & datos numéricos , Riesgo , Triticum/fisiología
11.
J Tissue Viability ; 26(2): 95-102, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28153472

RESUMEN

Critical limb ischemia (CLI) with distal leg necrosis in lung transplant recipients (LTR) is associated with a high risk for systemic infection and sepsis. Optimal management of CLI has not been defined so far in LTR. In immunocompetent individuals with leg necrosis, surgical amputation would be indicated and standard care. We report on the outcome of four conservatively managed LTR with distal leg necrosis due to peripheral arterial disease (PAD) with medial calcification of the distal limb vessels. Time interval from lung transplantation to CLI ranged from four years (n = 1) to more than a decade (n = 3). In all cases a multimodal therapy with heparin, acetylsalicylic acid, iloprost and antibiotic therapy was performed, in addition to a trial of catheter-based revascularization. Surgical amputation of necrosis was not undertaken due to fear of wound healing difficulties under long-term immunosuppression and impaired tissue perfusion. Intensive wound care and selective debridement were performed. Two patients developed progressive gangrene followed by auto-amputation during a follow-up of 43 and 49 months with continued ambulation and two patients died of unrelated causes 9 and 12 months after diagnosis of CLI. In conclusion, we report a conservative treatment strategy for distal leg necrosis in LTR without surgical amputation and recommend this approach based on our experience.


Asunto(s)
Isquemia/terapia , Pierna/irrigación sanguínea , Dedos del Pie/irrigación sanguínea , Receptores de Trasplantes , Adulto , Resultado Fatal , Femenino , Humanos , Huésped Inmunocomprometido , Isquemia/complicaciones , Pierna/diagnóstico por imagen , Recuperación del Miembro/métodos , Trasplante de Pulmón/efectos adversos , Masculino , Necrosis/complicaciones , Necrosis/terapia , Enfermedad Arterial Periférica/complicaciones , Radiografía , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Adulto Joven
12.
Phys Rev Lett ; 113(2): 026401, 2014 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-25062214

RESUMEN

Using femtosecond time-resolved x-ray diffraction, we directly monitor the coherent lattice dynamics through an ultrafast charge-density-wave-to-metal transition in the prototypical Peierls system K(0.3)MoO(3) over a wide range of relevant excitation fluences. While in the low fluence regime we directly follow the structural dynamics associated with the collective amplitude mode; for fluences above the melting threshold of the electronic density modulation we observe a transient recovery of the periodic lattice distortion. We can describe these structural dynamics as a motion along the coordinate of the Peierls distortion triggered by the prompt collapse of electronic order after photoexcitation. The results indicate that the dynamics of a structural symmetry-breaking transition are determined by a high-symmetry excited state potential energy surface distinct from that of the initial low-temperature state.

13.
Ann Bot ; 114(4): 863-75, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24989786

RESUMEN

BACKGROUND AND AIMS: Recent developments in plant disease management have led to a growing interest in alternative strategies, such as increasing host diversity and decreasing the use of pesticides. Use of cultivar mixtures is one option, allowing the spread of plant epidemics to be slowed down. As dispersal of fungal foliar pathogens over short distances by rain-splash droplets is a major contibutor to the spread of disease, this study focused on modelling the physical mechanisms involved in dispersal of a non-specialized pathogen within heterogeneous canopies of cultivar mixtures, with the aim of optimizing host diversification at the intra-field level. METHODS: Virtual 3-D wheat-like plants (Triticum aestivum) were used to consider interactions between plant architecture and disease progression in heterogeneous canopies. A combined mechanistic and stochastic model, taking into account splash droplet dispersal and host quantitative resistance within a 3-D heterogeneous canopy, was developed. It consists of four sub-models that describe the spatial patterns of two cultivars within a complex canopy, the pathway of rain-splash droplets within this canopy, the proportion of leaf surface area impacted by dispersal via the droplets and the progression of disease severity after each dispersal event. KEY RESULTS: Different spatial organization, proportions and resistance levels of the cultivars of two-component mixtures were investigated. For the eight spatial patterns tested, the protective effect against disease was found to vary by almost 2-fold, with the greatest effect being obtained with the smallest genotype unit area, i.e. the ground area occupied by an independent unit of the host population that is genetically homogeneous. Increasing both the difference between resistance levels and the proportion of the most resistant cultivar often resulted in a greater protective effect; however, this was not observed for situations in which the most resistant of the two cultivars in the mixture had a relatively low level of resistance. CONCLUSIONS: The results show agreement with previous data obtained using experimental approaches. They demonstrate that in order to maximize the potential mixture efficiency against a splash-dispersed pathogen, optimal susceptible/resistant cultivar proportions (ranging from 1/9 to 5/5) have to be established based on host resistance levels. The results also show that taking into account dispersal processes in explicit 3-D plant canopies can be a key tool for investigating disease progression in heterogeneous canopies such as cultivar mixtures.


Asunto(s)
Hongos/fisiología , Interacciones Huésped-Patógeno , Modelos Biológicos , Enfermedades de las Plantas/microbiología , Triticum/microbiología , Simulación por Computador , Resistencia a la Enfermedad , Hojas de la Planta/microbiología , Lluvia , Triticum/inmunología
14.
Pneumologie ; 68(6): 386-93, 2014 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-24715431

RESUMEN

Whereas pulmonary arterial hypertension is an orphan disease, the term pulmonary hypertension includes several common entities and is of major clinical significance. The pathophysiological triad of vasoconstriction, microthrombosis and vascular remodeling is found in most forms of pulmonary hypertension, independently of the underlying etiology. In this review, novel aspects in the pathogenesis of the remodeling, in particular microRNAs, will be discussed. MicroRNAs are small RNA fragments which bind specifically to the mRNA of a target gene thus decreasing its stability or inhibiting further translation ("gene silencing"). Of major interest is the association between microRNAs and the expression of bone morphogenetic protein receptor type II which has been found to be dysregulated on pulmonary endothelial and vascular smooth muscle cells in several forms of pulmonary hypertension. The specific inhibition of microRNAs by antagomiRs makes microRNAs a potential therapeutic target. Moreover, microRNAs are being validated in serum as biomarkers for diagnosis, severity and prognosis of pulmonary hypertension.


Asunto(s)
Pruebas Genéticas/métodos , Terapia Genética/métodos , Hipertensión Pulmonar/diagnóstico , Hipertensión Pulmonar/terapia , MicroARNs/sangre , MicroARNs/genética , Técnicas de Diagnóstico Molecular/métodos , Biomarcadores/sangre , Humanos , Hipertensión Pulmonar/genética
15.
Pneumologie ; 68(11): 719-26, 2014 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-25003906

RESUMEN

Molecular biomarkers are becoming increasingly significant in the workup of lung carcinoma patients. They assist in diagnosis, selecting the most adequate therapy and determining prognosis. Obtaining blood based biomarkers or volatile markers in exhaled breath may provide a less invasive method in the future. For the time being, bronchoscopy is still the method of choice to obtain specimen and assess tissue based biomarkers. The techniques how specimen are collected and processed for analysis are of paramount importance.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Bronquios/metabolismo , Broncoscopía/métodos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/metabolismo , Proteínas de Neoplasias/metabolismo , Humanos , Neoplasias Pulmonares/terapia , Cuidados Preoperatorios/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
16.
Ear Nose Throat J ; : 1455613231226046, 2024 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-38247118

RESUMEN

Tularemia is a rare disease but shows an approximately 10-fold increase in reported cases over the last 15 years in Germany. Clinical symptoms of acute tularemia infection are various, which often delays diagnosis. This case report gives an overview of the clinical manifestations of acute tularemia and shows the importance of interdisciplinary work to shorten the time from the onset of symptoms to effective treatment in infection with Francisella tularensis. Since some cases of tularemia are life-threatening, early diagnosis is vital. This case report serves as a reminder that rare diseases need to be considered in cervical lymphadenopathy.

17.
Anim Cogn ; 16(3): 483-92, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23269471

RESUMEN

Animals sometimes succeed quickly in solving a mechanical problem that is a modification of one they have previously learnt to solve. However, they may do so by attending to the visible features of the relevant physical dimension without knowing its causal functionality, if that is not directly perceivable. This kind of problem solving can be tested by simultaneously offering two mechanical devices with the same visual features but different inherent appropriateness for problem solving. Here, we provide data collected by following this procedure for the first time in a bird species. Captive kea, Nestor notabilis, a parrot species highly interested in the affordances of objects, were offered a mechanical problem in which they had to remove a baited tube from one of two upright poles where removal was blocked at the end of one pole but not the other. With extended but not with restricted exploration of a baseline apparatus, the kea immediately succeeded in removing the tube from an apparatus that had modified pole ends when they were able to visually observe (without touching) that one of these ends would block tube removal but the other would not. However, when the kea were allowed to explore two poles that had a removable and a fixed obstruction where the difference in function was not visible, they preferred the removable one during unbaited exploration but failed afterwards to push a tube to the end of the pole with the loose structure during subsequent baited test trials. Thus, in spite of the speed with which the kea learnt the tasks, there was no indication that they understood the underlying unobservable causal structure of the problem.


Asunto(s)
Loros , Animales , Cognición , Femenino , Masculino , Solución de Problemas , Percepción Visual
18.
Epidemiol Infect ; 141(6): 1244-52, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23200262

RESUMEN

In November 2009, we initiated a multistate investigation of Salmonella Montevideo infections with pulsed-field gel electrophoresis pattern JIXX01.0011. We identified 272 cases in 44 states with illness onset dates ranging from 1 July 2009 to 14 April 2010. To help generate hypotheses, warehouse store membership card information was collected to identify products consumed by cases. These records identified 19 ill persons who purchased company A salami products before onset of illness. A case-control study was conducted. Ready-to-eat salami consumption was significantly associated with illness (matched odds ratio 8·5, 95% confidence interval 2·1-75·9). The outbreak strain was isolated from company A salami products from an environmental sample from one manufacturing plant, and sealed containers of black and red pepper at the facility. This outbreak illustrates the importance of using membership card information to assist in identifying suspect vehicles, the potential for spices to contaminate ready-to-eat products, and preventing raw ingredient contamination of these products.


Asunto(s)
Capsicum/microbiología , Brotes de Enfermedades , Microbiología de Alimentos , Piper nigrum/microbiología , Intoxicación Alimentaria por Salmonella/etiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Niño , Preescolar , Comercio , Electroforesis en Gel de Campo Pulsado , Femenino , Abastecimiento de Alimentos , Humanos , Lactante , Masculino , Persona de Mediana Edad , Salmonella/clasificación , Intoxicación Alimentaria por Salmonella/epidemiología , Intoxicación Alimentaria por Salmonella/microbiología , Serotipificación , Estados Unidos/epidemiología , Adulto Joven
19.
Transl Anim Sci ; 7(1): txad121, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37965427

RESUMEN

At weaning, one hundred pigs (21 d of age; 6.96 ±â€…0.23 kg BW) were used to determine the effect of partially replacing soybean meal (SBM) in corn- and SBM-based nursery diets on growth performance, fecal scores, Escherichia coli (E. coli) colony forming units (CFU), and cecal mucosal microbial profile when weaned into non-disinfected nursery pens. Pens were randomly assigned to one of four dietary treatments (n = 5): high-complexity (contained highly digestible animal proteins and 10.8% SBM) with and without 3,000 ppm ZnO (HC + and HC-, respectively; representative of commercial diets), low-complexity (corn- and SBM-based; 31.8% SBM; LC), or LC with 30% inclusion of full-fat black soldier fly larvae meal (BSFLM) to partially replace SBM (LCFL; 8.0% SBM). Diets were fed for 14 d (phase I), followed by 4 wk of a common corn-SBM diet (phase II). Fecal E. coli CFU and cecal mucosal microbial 16s rRNA community profiles were assessed 7 d after weaning. During phase I, pigs fed LC and LCFL had lower average daily gains (P < 0.05) than pigs fed HC + and HC-, which were not different. Average daily feed intake was not different for pigs fed LC and LCFL, but lower than for pigs fed HC- (P < 0.001); pigs fed HC + had greater feed intake in phase I vs. all other treatment groups (P < 0.001). Upon nursery exit, only pigs fed LCFL had lower BW than pigs fed HC- (P < 0.05), with intermediate values observed for HC + and LC. Day 3 fecal scores were greater for pigs fed LCFL vs. HC + (P < 0.05) and day 7 E. coli CFU were greater for all treatment groups vs. HC + (P < 0.001). Pigs fed HC- (P < 0.01), LC (P < 0.05), and LCFL (P < 0.05) had lower alpha diversity for cecal mucosal microbiota compared to HC+. At the genus level, pigs fed LC had lower Lactobacillus relative abundance vs. pigs fed HC + (P < 0.01). Therefore, BSFLM can partially replace SBM without sacrificing growth performance vs. nursery pigs fed corn- and SBM-based diets, but both groups had reduced phase I growth performance vs. pigs fed highly digestible diets containing animal proteins when weaned into non-disinfected pens. The BSFLM did not influence fecal E. coli CFU or improve fecal consistency after weaning and therefore, is less effective at minimizing digestive upsets vs. HC + diets.

20.
Internist (Berl) ; 53(6): 756-9, 2012 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-22476211

RESUMEN

We report the case of a 76-year-old female patient presenting with deep venous thrombosis and upper cervical lymphadenopathy. A computed tomography (CT) scan showed multiple hepatic lesions with a high suspicion of metastatic disease from an unknown primary tumor. The differential diagnosis of lymphadenopathy and hepatic lesions includes malignant tumors and various infectious diseases. The diagnostic process, however, revealed lymph node tuberculosis with multiple hepatic granulomas despite a repeatedly negative interferon-γ release assay. A combined antituberculosis therapy led to complete clinical remission.


Asunto(s)
Tuberculosis Ganglionar/etiología , Tuberculosis Pulmonar/complicaciones , Tuberculosis Pulmonar/diagnóstico , Trombosis de la Vena/diagnóstico , Trombosis de la Vena/etiología , Anciano , Antituberculosos/uso terapéutico , Diagnóstico Diferencial , Femenino , Humanos , Resultado del Tratamiento , Tuberculosis Pulmonar/tratamiento farmacológico , Trombosis de la Vena/prevención & control
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