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1.
Phys Rev Lett ; 120(5): 055002, 2018 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-29481207

RESUMO

Electron-ion collisional dynamics is of fundamental importance in determining plasma transport properties, nonequilibrium plasma evolution, and electron damage in diffraction imaging applications using bright x-ray free-electron lasers (FELs). Here we describe the first experimental measurements of ultrafast electron impact collisional ionization dynamics using resonant core-hole spectroscopy in a solid-density magnesium plasma, created and diagnosed with the Linac Coherent Light Source x-ray FEL. By resonantly pumping the 1s→2p transition in highly charged ions within an optically thin plasma, we have measured how off-resonance charge states are populated via collisional processes on femtosecond time scales. We present a collisional cross section model that matches our results and demonstrates how the cross sections are enhanced by dense-plasma effects including continuum lowering. Nonlocal thermodynamic equilibrium collisional radiative simulations show excellent agreement with the experimental results and provide new insight on collisional ionization and three-body-recombination processes in the dense-plasma regime.

2.
Musculoskelet Surg ; 101(Suppl 2): 129-135, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29086336

RESUMO

PURPOSE: The reverse shoulder prosthesis (RSP) was developed to relieve pain and improve functional outcomes in patients with glenohumeral arthritis and deficiency of the rotator cuff. Even if clinical and functional outcomes regarding the use of the RSP were reported by literature, data concerning progressive deltoid adaptation to this non-anatomic implant are still missing. The purpose of our study was to correlate clinical and functional outcomes with deltoid fibers activity and muscle fatigability in patients with reverse shoulder prosthesis at 2 years follow-up. METHODS: Twenty patients with reverse shoulder prosthesis due to symptomatic deficient or nonfunctional rotator cuff associated with osteoarthritis were referred by Cervesi Hospital Shoulder and Elbow Surgery Unit. Exclusion criteria were: axillary nerve palsy, a nonfunctioning deltoid muscle, diabetes, previous trauma, malignancy. Furthermore patients who received the RSP for revision arthroplasty, proximal humerus fractures were excluded. All the patients underwent clinical and functional evaluation with the support of electromyography measurement focused on deltoid activity. RESULTS: RSP surgical treatment in shoulder osteoarthritis confirms his good outcome in terms of pain relief. At 2 years anterior and lateral deltoid electromyographic activity was significantly lower compared with contralateral side (p < 0.001). Posterior deltoid activity was no detectable. Range of motion at 2 years of follow-up decreased in terms of forward flexion (p = 0.045), abduction (p = 0.03) and external rotation (p < 0.001). CONCLUSIONS: Our study demonstrates that even if the patients remain pain-free, progressive deterioration of the deltoid activity is unavoidable and may lead to poor functional outcomes overtime.


Assuntos
Artroplastia do Ombro , Músculo Deltoide/fisiopatologia , Adaptação Fisiológica , Idoso , Idoso de 80 Anos ou mais , Eletromiografia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Fadiga Muscular , Osteoartrite/cirurgia , Amplitude de Movimento Articular , Lesões do Manguito Rotador/fisiopatologia , Lesões do Manguito Rotador/cirurgia , Artropatia de Ruptura do Manguito Rotador/fisiopatologia , Artropatia de Ruptura do Manguito Rotador/cirurgia , Prótese de Ombro , Resultado do Tratamento
3.
Phys Rev Lett ; 119(5): 055001, 2017 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-28949745

RESUMO

We present new experiments to study the formation of radiative shocks and the interaction between two counterpropagating radiative shocks. The experiments are performed at the Orion laser facility, which is used to drive shocks in xenon inside large aspect ratio gas cells. The collision between the two shocks and their respective radiative precursors, combined with the formation of inherently three-dimensional shocks, provides a novel platform particularly suited for the benchmarking of numerical codes. The dynamics of the shocks before and after the collision are investigated using point-projection x-ray backlighting while, simultaneously, the electron density in the radiative precursor was measured via optical laser interferometry. Modeling of the experiments using the 2D radiation hydrodynamic codes nym and petra shows very good agreement with the experimental results.

4.
Comput Biol Med ; 72: 248-55, 2016 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-26724992

RESUMO

One of the most important problems in the pharmacy department of a hospital is stock management. The clinical need for drugs must be satisfied with limited work labor while minimizing the use of economic resources. The complexity of the problem resides in the random nature of the drug demand and the multiple constraints that must be taken into account in every decision. In this article, chance-constrained model predictive control is proposed to deal with this problem. The flexibility of model predictive control allows taking into account explicitly the different objectives and constraints involved in the problem while the use of chance constraints provides a trade-off between conservativeness and efficiency. The solution proposed is assessed to study its implementation in two Spanish hospitals.


Assuntos
Inventários Hospitalares , Modelos Organizacionais , Serviço de Farmácia Hospitalar/organização & administração
5.
Arch Environ Contam Toxicol ; 60(3): 444-51, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20607530

RESUMO

Behavioural responses are linked to complex biochemical and physiologic changes and may act as sensitive indicators of the sublethal effects of pollutants. This article investigates changes in the locomotor activity rhythms of the amphipod Gammarus aequicauda exposed to cadmium (Cd) as a model to study the effect of pollutants on an ecologically important species. Under a 12:12 h light-to-dark cycle, G. aequicauda showed a strict nocturnal rhythm, with 90.2±0.4% of their total daily activity occurring during the night. Under constant darkness, circadian rhythms persisted for 10 days, with a mean periodicity of 24.32 h, thus confirming endogenous control. Exposure to sublethal concentrations of Cd (0.16, 0.20, 0.24, and 0.28 mg l(-1)) did not change the nocturnal activity patterns of G. aequicauda, although their swimming activity during the night was significantly decreased by exposure to concentrations of 0.24 and 0.28 mg Cd l(-1). In conclusion, locomotor activity bioassays using the amphipod G. aequicauda appeared to be a sensitive indicator of Cd contamination, and sensitivity and tolerance to Cd in short-term bioassays may depend on the time of the day tests are carried out. These results provide further support for the idea that behavioural end points in amphipods are useful indicators of pollutant exposure and that future studies should take circadian rhythms into consideration.


Assuntos
Anfípodes/efeitos dos fármacos , Anfípodes/fisiologia , Cádmio/toxicidade , Animais , Ritmo Circadiano/efeitos dos fármacos , Feminino , Atividade Motora/efeitos dos fármacos , Fotoperíodo
6.
Opt Lett ; 34(17): 2640-2, 2009 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-19724517

RESUMO

Plasma-based seeded soft x-ray lasers have the potential to generate a high-energy, highly coherent, short pulse beam. Owing to their high density, plasmas created by interaction of an intense laser with a solid target should store the highest amount of energy among all plasma amplifiers. However, to date output energy from seeded solid amplifiers remains as low as 60 nJ. We demonstrated that careful tailoring of the plasma shape is crucial for extracting energy stored in the plasma. With 1-mm-wide plasma, energy as high as 20 microJ in sub-ps pulses is achievable. With such tailored plasma, gain and pumping efficiency have been increased by nearly a factor of 10 as compared to the narrower plasma amplifiers studied here.

7.
Rev Neurol ; 47(9): 464-8, 2008.
Artigo em Espanhol | MEDLINE | ID: mdl-18985595

RESUMO

INTRODUCTION: Inflammatory pseudotumor is a reactive process in which the etiology and pathogenesis are not well defined, that can be found in any location. The cases with central nervous system affection have been described in meninges, brain, choroid plexus and cranial and spinal nerves. Multicentric cases, synchronous and asynchronous have been described. CASE REPORT: A 45 years-old woman with a rheumatologic disease (a seronegative spondiloarthropathy) who developed an inflammatory pseudotumor in spleen, liver and abdominal lymph nodes in 1995, associated to fever of unknown origin, six years later she presented with an inflammatory pseudotumor of the meninges in the convexity of the right frontoparietal region, with fever, malaise, and increase of globular sedimentation rate, microcytic hypochromic anemia and thrombocytosis. CONCLUSION: The clinicopathologic features of this lesion are revised, including the different theories in regard to the etiology and pathogenesis, and the role of cytokines produced by inflammatory cells in the tumor.


Assuntos
Granuloma de Células Plasmáticas/patologia , Fígado/patologia , Linfonodos/patologia , Meninges/patologia , Baço/patologia , Espondiloartropatias/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Literatura de Revisão como Assunto
8.
J Agric Food Chem ; 55(12): 4828-34, 2007 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-17511468

RESUMO

The addition of organic amendments to soil increases soil organic matter content and stimulates soil microbial activity. Thus, processes affecting herbicide fate in the soil should be affected. The objective of this work was to investigate the effect of olive oil production industry organic waste (alperujo) on soil sorption-desorption, degradation, and leaching of diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea] and terbuthylazine [N2-tert-butyl-6-chloro-N4-ethyl-1,3,5-triazine-2,4-diamine], two herbicides widely used in olive crops. The soils used in this study were a sandy soil and a silty clay soil from two different olive groves. The sandy soil was amended in the laboratory with fresh (uncomposted) alperujo at the rate of 10% w/w, and the silty clay soil was amended in the field with fresh alperujo at the rate of 256 kg per tree during 4 years and in the laboratory with fresh or composted alperujo. Sorption of both herbicides increased in laboratory-amended soils as compared to unamended or field-amended soils, and this process was less reversible in laboratory-amended soils, except for diuron in amended sandy soil. Addition of alperujo to soils increased half-lives of the herbicides in most of the soils. Diuron and terbuthylazine leached through unamended sandy soil, but no herbicide was detected in laboratory-amended soil. Diuron did not leach through amended or unamended silty clay soil, whereas small amounts of terbuthylazine were detected in leachates from unamended soil. Despite their higher sorption capacity, greater amounts of terbuthylazine were found in the leachates from amended silty clay soils. The amounts of dissolved organic matter from alperujo and the degree of humification can affect sorption, degradation, and leaching of these two classes of herbicides in soils. It appears that adding alperujo to soil would not have adverse impacts on the behavior of herbicides in olive production.


Assuntos
Diurona/análise , Óleos de Plantas/química , Solo/análise , Triazinas/análise , Eliminação de Resíduos Líquidos , Diurona/química , Manipulação de Alimentos , Herbicidas/análise , Luz , Azeite de Oliva , Triazinas/química
10.
Rev. investig. UNSAAC ; 1: 29-32, dic. 2001. ilus
Artigo em Espanhol | LIPECS | ID: biblio-1110576

RESUMO

El objetivo de este estudio fue el de identificar los componentes de un agroecosistema en Pumamarca (Cusco) para diseñar un programa orientado al manejo racional de los recursos naturales al interior del agroecosistema. La colección de artrópodos se hizo usando dos métodos de colección: a) Trampas de caída, b) Red entomológica. Las muestras se tomaron en el interior del campo de cultivo así como en el borde, los muestreos fueron realizados mediante transectos. El tratamiento estadístico se realizó con datos no transformados determinando el índice de diversidad de Simpson. La evaluación de aves predadoras se hizo a través de observación directa. La composición de los diferentes niveles trópicos se hizo con un programa Visio. El índice de diversidad de Simpson (=.862) indica una alta diversidad registrándose dos picos poblacionales para la mayoría de taxa encontrados. El segundo pico poblacional puede deberse a una reinfestación tanto de las plagas como de sus enemigos naturales, los cuales pueden encontrarse en hospederos secundarios, de los cuales se desplazaron en busca de presas u hospederos. Se han identificado varios niveles en la cadena trófica: a) Productores primarios, entre los cuales se encuentran plantas silvestres y cultivadas, b) fitófagos e insectos que se alimentan de plantas cultivadas, c) Consumidores de primer nivel, predadores y parasitoides que se alimentan de fitófagos, d) Consumidores de segundo nivel, predadores y parasitoides que se alimentan de consumidores de primer nivel, e) Consumidores de tercer nivel, insectívoros como el pichinko (Zonotrichia capensis), f) consumidores de cuarto nivel como el Killicho (Falco sparverius) que preda en insectívoros, g) descomponedores, como Collembola, Acari y otros. ...


Assuntos
Biota , Peru
11.
Ann Thorac Surg ; 46(3): 349-50, 1988 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3261971

RESUMO

Fifteen years after aortocoronary bypass surgery, a 52-year-old asymptomatic man was found to have a large anterior mediastinal mass. Angiographic studies showed no evidence that a vascular structure was responsible. At operation, a saphenous vein graft to the left anterior descending artery was found to be affected by a large thrombus-filled aneurysm. This is one of the few known cases in which such an aneurysm has presented as a mediastinal mass.


Assuntos
Aneurisma/diagnóstico por imagem , Ponte de Artéria Coronária , Neoplasias do Mediastino/diagnóstico por imagem , Veia Safena , Aneurisma/etiologia , Aneurisma/cirurgia , Diagnóstico Diferencial , Humanos , Masculino , Pessoa de Meia-Idade , Reoperação , Fatores de Tempo , Tomografia Computadorizada por Raios X
12.
Tex Heart Inst J ; 15(3): 174-82, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-15227248

RESUMO

This article reexamines the subject of ventriculoarterial discordance in the light of a case report and the recent literature. The angiographic method of studying complex cardiac defects is illustrated by example, in order to stress the need for a systematic, step-by-step, segmental approach to diagnosis. We favor use of the term "ventriculoarterial" discordance to refer to a defect that involves incongruence of ventricular and arterial morphologies, as predicated on the loop rule. This rule calls for anticipation of certain spatial relationships between aortic and pulmonary trunks, given certain ventricular morphologies: with a right-sided, anatomically right ventricle, for example, the ascending aorta is expected to be on the right side, whether with normally crossed or transposed great vessels (D-loop derivatives). As in the case presented here, ventriculoarterial discordance features the ascending aorta on the opposite side of the anatomically right ventricle. The influence of the formation of an abnormal cardiac apex (as in crisscrossed or superoinferior hearts) on the cardiac segments' configurations is discussed, since this too can affect the spatial relationships between the great vessels.

13.
Tex Heart Inst J ; 14(1): 53-6, 1987 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15227330

RESUMO

Over a 3-year period, we performed 232 consecutive percutaneous transluminal coronary angioplasty (PTCA) procedures in 171 patients, 132 (77%) of whom were men and 39 (23%) of whom were women. The patients' ages ranged from 26 to 85 years (average, 56.5 years). All of the patients had symptoms of coronary insufficiency, manifested by stable angina in 106 cases, unstable angina in 44 cases, post myocardial infarction angina in 19 cases, arrhythmia in 1 case, and syncope in 1 case. All PTCA dilatations were done by the same operators, using the same technique. The procedures were categorized as follows: Group 1 included 157 single-vessel PTCA procedures, which had a success rate of 87.3%; these included 52 dilatations of the right coronary artery (success rate, 84%), 94 dilatations of the left anterior descending artery (success rate, 86%), and 11 dilatations of the left circumflex system (success rate, 90%). Group 2 included 29 double-vessel PTCA procedures (58 total procedures), which had an 88% success rate, and group 3 comprised 17 vein-graft PTCAs, with an 86.9% success rate. Complications included coronary artery occlusion in 15 cases (9.0%), myocardial infarction in four cases (2.3%), and cardiac arrhythmia in one case (0.6%). There were no deaths. Fifteen patients (8.8%) underwent coronary artery bypass surgery during the same hospitalization (3.8% of these operations were performed on an emergency basis). Thirty-six patients (15.5%) had a second PTCA procedure owing to restenosis, which occurred either before the patient was discharged from the hospital (eight cases) or 3 to 30 months after the original procedure. We conclude that, when performed by experienced operators with optimal technical resources, PTCA results in an acceptable success rate; therefore, this procedure should be a satisfactory method of myocardial revascularization in well-selected patients with either single- or double-vessel coronary artery disease.

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