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1.
Phys Rev E ; 109(4-1): 044106, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38755890

RESUMO

In modern democracies, the outcome of elections and referendums is often remarkably tight. The repetition of these divisive events are the hallmark of a split society; to the physicist, however, it is an astonishing feat for such large collections of diverse individuals. Many sociophysics models reproduce the emergence of collective human behavior with interacting agents, which respond to their environment according to simple rules, modulated by random fluctuations. A paragon of this class is the Ising model which, when interactions are strong, predicts that order can emerge from a chaotic initial state. In contrast with many elections, however, this model favors a strong majority. Here we introduce a new element to this classical theory, which accounts for the influence of opinion polls on the electorate. This brings about a new phase in which two groups divide the opinion equally. These political camps are spatially segregated, and the sharp boundary that separates them makes the system size dependent, even in the limit of a large electorate. Election data show that, since the early 1990s, countries with more than about a million voters often found themselves in this state, whereas elections in smaller countries yielded more consensual results. We suggest that this transition hinges on the electorate's awareness of the general opinion.

4.
Rev Sci Instrum ; 93(10): 103512, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36319325

RESUMO

Hard x-ray (HXR) spectroscopy is applied for diagnostics of runaway electrons in nuclear fusion reactors. The scintillation counter is one of the most commonly used types of detectors for HXR spectroscopy. It consists of a detector that emits light when excited by HXR radiation (scintillator) directly coupled to a PMT (Photomultiplier Tube) that converts light pulses into an electrical signal. This type of detector is commonly used in existing tokamaks, such as Joint European Torus (JET), Experimental Advanced Superconducting Tokamak (EAST), Compact Assembly (COMPASS), and Axially Symmetric Divertor Experiment (ASDEX-U). In all these cases, the scintillator is directly coupled to the PMT to provide the best possible light transmission efficiency. The Hard X-ray Monitor (HXRM) is one among the first plasma diagnostic systems at ITER that provides information about the energy distribution of runaway electrons inside a tokamak by HXR spectroscopy. This system also uses a scintillator and a PMT as a detector. Due to the heavy shielding of the blanket modules, vacuum vessel, and port-plugs, it is not possible to assemble the scintillator outside the tokamak vacuum vessel. The PMT detector cannot be installed in the close vicinity of the tokamak due to either the significant magnetic field or temperature. A possible solution is to decouple the scintillator from the PMT and place the PMT inside the port-cell. Light pulses will be transmitted to the PMT via a 12 m long optical fiber bundle. Evaluation of the optical transmission was carried out to assess the performance of the HXR monitor and verify possible problems related to the PMT pulse discrimination under low light conditions.

5.
Interface Focus ; 11(1): 20200006, 2021 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-33343876

RESUMO

The goal of this paper is to present a dedicated high-performance computing (HPC) infrastructure which is used in the development of a so-called reduced-order model (ROM) for simulating the outcomes of interventional procedures which are contemplated in the treatment of valvular heart conditions. Following a brief introduction to the problem, the paper presents the design of a model execution environment, in which representative cases can be simulated and the parameters of the ROM fine-tuned to enable subsequent deployment of a decision support system without further need for HPC. The presentation of the system is followed by information concerning its use in processing specific patient cases in the context of the EurValve international collaboration.

6.
J Chem Phys ; 152(11): 114902, 2020 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-32199445

RESUMO

We study the critical Casimir interaction between two spherical colloids immersed in a binary liquid mixture close to its critical demixing point. The surface of each colloid prefers one species of the mixture with the exception of a circular patch of arbitrary size, where the other species is preferred. For such objects, we calculate, within the Derjaguin approximation, the scaling function describing the critical Casimir potential, and we use it to derive the scaling functions for all components of the forces and torques acting on both colloids. The results are compared with available experimental data. Moreover, the general relation between the scaling function for the potential and the scaling functions for the force and the torque is derived.

7.
J Dairy Sci ; 99(1): 57-67, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26506539

RESUMO

The effect of administration of lipid complex (LC) on cow milk and cheese characteristics was studied. Lipid complex was elaborated based on grapeseed oil with synthesized conjugated linoleic acid (CLA) and Atlantic mackerel oil enriched in n-3 fatty acids. The 4-wk experiment was conducted on 30 Polish Holstein Friesian cows. The experimental group cow diet was supplemented with 400 g/d of LC (containing 38% CLA, and eicosapentaenoic acid + docosahexaenoic acid in a relative amount of 36.5%) on a humic-mineral carrier. The chemical composition and fatty acid profile of milk and rennet cheese from raw fresh milk were analyzed. Lipid complex supplementation of the total mixed ration had no effect on milk yield and milk composition, except fat content, which decreased from 4.6 to 4.1%, a 10.9% decrease. Milk from cows treated with LC had greater relative amounts of unsaturated fatty acids, particularly polyunsaturated fatty acids, and lesser relative amounts of saturated fatty acids. Lipid complex addition changed milk fat fatty acid profile: C18:2 cis-9,trans-11 and trans-10,cis-12 isomer (CLA) contents increased by 278 and 233%, respectively, as did eicosapentaenoic acid (C20:5) and docosahexaenoic acid (C22:6) contents. Milk fat fatty acid profile changes were correlated with the modifications in rennet cheese fatty acid profile. Lipid complex supplementation of dairy cows produced considerable changes in the biological value of milk and cheese fat.


Assuntos
Queijo/análise , Óleos de Peixe/farmacologia , Ácidos Linoleicos Conjugados/farmacologia , Lipídeos/análise , Leite/química , Óleos de Plantas/farmacologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bovinos/metabolismo , Perciformes , Vitis/química
8.
J Microsc ; 237(3): 246-52, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20500374

RESUMO

RuO(2) thin films have been deposited on Si substrates by spin coating with precursor solutions having a pH varying between 1.4 and 4. X-ray diffraction and transmission electron microscopy analyses are used to determine correlations between the solution pH and the film microstructure. As the pH varies, the RuO(2) crystal sizes reach a minimum value then increase; the porosity increases at the substrate/film interface with formation of large cavities. The catalytic activity of these RuO(2) layers in the presence of flowing air-methane is analysed by Fourier transform infrared spectroscopy of the conversion of CH(4) into CO(2). The increasing porosity seems to improve the catalytic conversion rate of methane. Electrical impedance spectroscopy analyses show that the conductivity strongly depends on the thin-film microstructure and porosity.

9.
Transplant Proc ; 41(8): 3033-5, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19857669

RESUMO

To ensure appropriate function of the transplanted organ, it is necessary to adequately maintain vascular volume during the kidney transplantation procedure. For this purpose, central venous pressure (CVP) is monitored through a catheter inserted into the superior vena cava (SVC). Central venous cannulation is associated with a risk of serious complications. An objective of this study was to investigate whether there was a correlation between pressures measured in the SVC and in the external jugular vein (EJV). We studied 33 chronically dialyzed patients who had a short catheter placed in the EJV because of difficulties in peripheral vein cannulation in the limbs. In each case, general anesthesia was induced and a central catheter inserted into the SVC. Every 10 minutes venous pressure measurements were obtained simultaneously at both sites. A significant (P < .001) correlation was observed between external jugular vein pressure (EJVP) and CVP. CVP could be described as a function of EJVP by the equation CVP = {0.90299 x EJVP} - 0.8361. The results of this study indicated that monitoring the EJVP allows equally efficient evaluation of vascular volume as the CVP. In our opinion, EJVP is sufficient to evaluate vascular volume during kidney transplantation in patients with difficult vascular access.


Assuntos
Pressão Sanguínea , Veias Jugulares/fisiologia , Transplante de Rim/fisiologia , Adulto , Braço/irrigação sanguínea , Índice de Massa Corporal , Cateterismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Veia Cava Superior/fisiologia
10.
Dis Esophagus ; 20(4): 358-60, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17617887

RESUMO

Esophageus or gaster resection in patients with malignant disease is still a treatment of choice. It is obvious that each surgical procedure in these patients carries some possibility of complications. Esophageo-gastric or esophageo-jejuno anastomosis has a 4-27% frequency of fistula occurrence. All these result in 65% mortality in cases of poorer prognosis. The aim of this paper is not to present all types of complications but to objectively analyse the usefulness of the covered stent placement in the treatment of anastomotic fistulas. We present six patients who were treated for postoperative fistula of esophageo-gastric anastomosis (1 case) or esophageo-jejuno anastomosis (5 cases). All patients were treated with stapler suture for digestive tract reconstruction after malignancy removal during the primary surgical procedure. Signs and symptoms of suture leak between 5-8 days post-surgery were observed. Conservative therapy was not effective. Thus a new method of treatment was employed - covered stent placement. The procedure was performed under X-ray control. In all treated patients there was change for the better and quick reduction of secretion from the fistulas was observed. All patients were discharged from the department after several days and all had survived at 30 days follow-up. Covered esophageal stent placement seems to be a safe and promising method of treatment for patients with anastomotic fistula which significantly reduces mortality and improves quality of live. Our experiences confirms that of other investigators.


Assuntos
Fístula Esofágica/cirurgia , Esofagostomia/efeitos adversos , Fístula Gástrica/cirurgia , Gastrostomia/efeitos adversos , Fístula Intestinal/cirurgia , Doenças do Jejuno/cirurgia , Jejunostomia/efeitos adversos , Stents , Fístula Esofágica/etiologia , Feminino , Fístula Gástrica/etiologia , Humanos , Fístula Intestinal/etiologia , Doenças do Jejuno/etiologia , Masculino , Pessoa de Meia-Idade , Desenho de Prótese
11.
J Anim Sci ; 83(4): 871-8, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15753343

RESUMO

A 2 x 2 factorial arrangement of treatments with 78 mature ewes was used to evaluate the effects of supplementing the pregnant ewe's diet with high levels of minerals and vitamin E on immunoglobulin G (IgG) absorption by the lamb and whether any altered efficacy of IgG absorption was due to the colostrum or to the lamb. The ewes were estrus-synchronized in October and housed in wk 10 of gestation. In the final 7 wk of gestation, a grass silage-based diet, offered ad libitum, was supplemented with 500 g of a 19% CP concentrate, and from 1 wk later until lambing, half the ewes was offered 48 g of a mineral/vitamin supplement containing 6.5 g of Ca, 4.9 g of P, 5.9 g of Mg, 4.0 g of Na, 790 mg of Zn, 3.5 mg of Se, 40 mg of I, 200 mg of Mn, 20 mg of Co, and 40 IU of vitamin E. At birth, the lambs were allocated to one of four treatments in a 2 x 2 factorial arrangement, with lamb origin and colostrum origin as the two factors. The lambs born to ewes not offered the mineral supplement were fed colostrum obtained from their own dams or from ewes in the mineral-supplemented treatment, whereas lambs born to ewes given supplemental minerals were fed colostrum obtained either from their dams or from ewes in the control treatment. The ewes were milked at 1, 10, and 18 h postpartum and the lambs were fed using a stomach tube. A 5-mL blood sample was taken from each lamb at 24 h postpartum for IgG analysis. The level of fecal adhesion to the upper tail/rump area of the lamb was subjectively scored at 72 h postpartum. There was no difference in gestation length, lamb birth weight, colostrum yield, or IgG production (P = 0.16 to 0.82). When ewes were fed supplemental minerals, the serum IgG content of the progeny was lower than in their control counterparts (6.8 vs. 16.1 g/L; P < 0.001), regardless of whether the lamb received colostrum from ewes with or without access to supplementary minerals. The difference in serum IgG concentrations at 24 h postpartum was a direct reflection of a compromised efficiency in IgG absorption. The progeny of ewes with access to minerals had higher (P < 0.05) levels of fecal adhesion, which was not related to the origin of the colostrum, indicating altered digestive function in these lambs. We conclude, using the sheep as a model, that high mineral intakes in late pregnancy not only lower serum IgG concentrations in the lamb, but also that high mineral intakes result in the neonate being preprogrammed at birth so that it is born with a compromised ability to absorb colostral IgG.


Assuntos
Colostro/efeitos dos fármacos , Suplementos Nutricionais , Imunoglobulina G/metabolismo , Minerais/farmacologia , Ovinos/fisiologia , Vitamina E/farmacologia , Absorção , Ração Animal/análise , Animais , Peso ao Nascer/efeitos dos fármacos , Colostro/imunologia , Digestão/efeitos dos fármacos , Fezes , Feminino , Imunoglobulina G/sangue , Imunoglobulina G/fisiologia , Minerais/administração & dosagem , Gravidez , Distribuição Aleatória , Vitamina E/administração & dosagem
12.
Acta Chir Orthop Traumatol Cech ; 70(4): 207-13, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14569856

RESUMO

PURPOSE OF THE STUDY: The aim of this study was to assess the results of surgical treatment of 58 patients with pectus excavatum and 11 with pectus carinatum and discuss the problems connected with ethiopathogenesis and operative techniques. MATERIAL: 69 chest deformations treated between 1961-2001. METHODS: The clinical results were analyzed with 1) Kopera-Król Rtg-index, 2) Gizycka's Rtg-index of chest flattening, 3) Haller and Nakahara CT-index, 4) Heart position after operation, 5) Frequency of upper respiratory infections, 6) Appearance of postoperative scar, 7) Patient's opinion. Histopathological investigations were used to assess ethiopathogenesis of chest deformations. RESULTS: 90% permanent correction achieved in group of patients operated in the age from 12 to 17. Otherwise we noted between the patients who were operated in the age from 6 to 10-37% recurrence of deformity. Generally we had 70% excellent and good results. The opinion of patients (including cosmetics effects, psychical state and exercise tolerance) was much better-86.6%. Particularly correction of pectus carinatum gives good cosmetics effects as well as improvement of exercise tolerance. DISCUSSION: Nuss modified correction employing a substernal stabilizing plate is an alternative for transsternal traction in the classical Ravitsch' procedure. Authors present advantages and disadvantages of both methods. The optimal age for surgical correction and inter and post operative procedure are discussed. CONCLUSIONS: Ethipathogenesis of pectus excavatum and carinatum remains unsettled. Disturbances in endochondral ossification and growth of costal cartilage seem to be more probable cause of the deformities than diaphragm underdevelopment. Mild and severe forms of the two deformities result in circulatory-respiratory malfunctions, cosmetic defects and psychical problems. Due to possible circulatory-respiratory disorder, appropriate premedication as well as intra- and postoperative monitoring of RR, ECG, O2, CO2 are very important on the first day after the surgery. Ravistch-Garnier procedure for pectus excavatum and Chen procedure for pectus carinatum remain operations of choice. Transsternal traction can be replaced with internal stabilisation with a bar placed under the sternum what considerably reduces the time of hospitalisation but requires one more hospitalisation to remove the bar. Correction of pectus carinatum is permanent, correction of pectus excavatum turned out to be permanent in 90% cases providing that they were performed in patients aged 12-16. When patients were at the age 6-10, recurrence of the deformity occurred in 37% of cases. According to the clinical assessment, in both age groups, the proportion of very good or good scores equalled 70% and according to patient's evaluation--86.6%.


Assuntos
Parede Torácica/anormalidades , Parede Torácica/cirurgia , Adolescente , Criança , Tórax em Funil/cirurgia , Humanos
13.
Wiad Lek ; 54(9-10): 516-21, 2001.
Artigo em Polonês | MEDLINE | ID: mdl-11816295

RESUMO

Peripheral arteries disorders cause not only leg ischaemia, but also peripheral polyneuropathy. Polyneuropathy increases ischaemic pain. The aim of this study was to estimate how many patients suffering from critical leg ischaemia have symptoms of peripheral polyneuropathy. 40 patients were investigated: 37 men and 3 women; mean age was 57 years. All patients underwent electroneurographic examination. It consisted of measurements of motor conduction in tibial and peroneal nerves, wave F, sensory conduction in sural nerve. Polyneuropathy was observed in 95% of patients. The frequency of polyneuropathy was also significantly enlarged in leg with non critical ischaemia. We did not observe the greater risk of polyneuropathy in diabetic patients. The work is an introduction to the following clinical studies.


Assuntos
Isquemia/diagnóstico , Perna (Membro)/irrigação sanguínea , Perna (Membro)/inervação , Condução Nervosa , Polineuropatias/fisiopatologia , Adulto , Idoso , Feminino , Humanos , Isquemia/etiologia , Isquemia/fisiopatologia , Masculino , Pessoa de Meia-Idade , Nervo Fibular/fisiopatologia , Nervo Tibial/fisiopatologia
14.
Wiad Lek ; 53(11-12): 701-5, 2000.
Artigo em Polonês | MEDLINE | ID: mdl-11247416

RESUMO

A case of 69-year-old male patient with recurrent abdominal aortic aneurysm is described. The patient had been successfully operated on for infrarenal abdominal aortic aneurysm 4 years before, and 2 months postoperatively dilatation of juxtarenal part of abdominal aorta was diagnosed in ultrasonic examination. Due to progressive enlargement of juxtarenal aneurysm the patient was admitted to hospital again and operated on. Excision of aneurysm with implantation of both renal arteries to the prosthesis was done. The perioperative course was uneventful. Authors emphasize the importance of evaluation of abdominal aorta after operative treatment of aneurysm (ultrasonic, CT, MRI) to diagnose recurrent aneurysms.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Idoso , Aneurisma da Aorta Abdominal/diagnóstico , Prótese Vascular , Seguimentos , Humanos , Masculino , Recidiva , Artéria Renal/transplante , Reoperação
15.
Wiad Lek ; 52(11-12): 587-90, 1999.
Artigo em Polonês | MEDLINE | ID: mdl-10745696

RESUMO

The occurrence of the postcholecystectomy syndrome is very often connected with inappropriate preoperative diagnostics. One of the reasons might be the presence of gastric or duodenal ulcer, what can be connected with peri- and late postoperative complications. The prospective analysis of 250 patients admitted to the Department because of cholelithiasis was performed. In 28.8% of cases endoscopical changes in the upper alimentary tract were recognized. That is why, in patients qualified for cholecystectomy the upper alimentary tract endoscopy should be performed.


Assuntos
Colecistectomia/métodos , Colelitíase/diagnóstico , Colelitíase/cirurgia , Erros de Diagnóstico , Complicações Pós-Operatórias , Cuidados Pré-Operatórios , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Síndrome
16.
J Spinal Disord ; 10(5): 410-6, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9355058

RESUMO

This study assesses the ability of a two-stage treadmill test to distinguish stenotic from nonstenotic subjects by capitalizing on the postural dependency of stenotic symptoms. Forty-five subjects (26 stenotic, 19 nonstenotic) participated. An earlier onset of symptoms with level walking (p = 0.0009), increased total walking time on an inclined treadmill (p = 0.014), and prolonged recovery time after level walking (p = 0.001) were significantly associated with stenosis. Only one of four self-reported postural variables were significantly associated with stenosis. Linear discriminant analysis performed using the treadmill variables resulted in the correct classification of 76.9 and 94.7% of stenotic and nonstenotic subjects, respectively. Likelihood ratios for all treadmill variables were > 2.50, and < 2.00 for all self-report variables. A two-stage treadmill test may be useful in the differential diagnosis of lumbar stenosis, and clinical measurement of the postural nature of symptoms seems to be superior to subjects' self-reports.


Assuntos
Dor Lombar/diagnóstico , Estenose Espinal/diagnóstico , Adulto , Idoso , Diagnóstico Diferencial , Teste de Esforço/métodos , Feminino , Humanos , Vértebras Lombares , Masculino , Pessoa de Meia-Idade , Medição da Dor , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Caminhada
18.
Phys Ther ; 76(2): 187-90, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8592723

RESUMO

Symptoms for spinal stenosis apparently result from an incongruity between the capacity and contents of the spinal nerve passages. These symptoms are most frequently seen in men in their fifth or sixth decade of life. Spinal extension generally exacerbates the claudication-type symptoms (lower-extremity pain and paresthesia), whereas spinal flexion diminishes these symptoms. Differential diagnosis is needed to rule out vascular claudication due to atherosclerosis. Decisions regarding surgery should be made based not only on diagnostic imaging but also on a thorough history and clinical examination.


Assuntos
Estenose Espinal/fisiopatologia , Diagnóstico por Imagem , Humanos , Laminectomia , Fusão Vertebral , Estenose Espinal/diagnóstico , Estenose Espinal/cirurgia
19.
Theriogenology ; 42(4): 613-22, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16727567

RESUMO

Observations relating testes size to body weight in growing and adult Polish Merino rams were performed during 3 consecutive years in a flock of 1700 pedigree ewes. October-born ram lambs were measured for testis diameter (TD), scrotal circumference (SC), and body weight (BW) at 100 (January), 150 (March), 180 (April), 240 (June), 365 (October), and 480 d (February) of age. In adult rams (n = 63 to 73 per year) BW and SC were measured in March, May (prior to breeding), August and October. Semen quality was evaluated before each breeding season, and the results of controlled reproductive performance (2 natural services to designated rams) were analyzed. Indices were applied to relate testis size to body weight: TD BW , SC BW and TW BW . Heritability estimates of testes indices in ram lambs at 100 to 240 d and at 480 d of age ranged from 0.21 to 0.36 (SE = 0.067 to 0.090). In adult rams SC measurements within months in consecutive years were repeatable (r = 0.55 to 0.68; P< or =0.01). Single measurements of adult ram gonads were not related to other reproductive traits, but significant relations were found when dynamic changes in testes size were examined as the percentage of testes weight change from March to May. Consistent correlations (positive or negative r = 0.2 to 0.5; P < or = 0.01) between seasonal changes in adult ram testes, semen quality, reproductive performance and in testes size in growing ram lambs were observed. The data suggest that the best time for selecting Polish Merino rams for a seasonality in reproduction is in March at 150 d of age.

20.
J Neurosci Nurs ; 25(5): 313-16, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7903677

RESUMO

The epidural route of administration can be used safely for acute and chronic pain control. Although most frequently used in the obstetrical setting, the epidural route has been used more recently for pain control in general surgical and oncology patients. Nursing policies, physician order sets and nursing documentation provide a consistent approach to patients receiving epidural analgesia. Continuous quality improvement helps to assure patient satisfaction and program quality.


Assuntos
Analgesia Epidural/enfermagem , Dor Pós-Operatória/enfermagem , Analgésicos Opioides/administração & dosagem , Analgésicos Opioides/efeitos adversos , Cateteres de Demora , Humanos , Avaliação em Enfermagem , Medição da Dor , Satisfação do Paciente , Garantia da Qualidade dos Cuidados de Saúde
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