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1.
Nat Commun ; 11(1): 1726, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32265449

RESUMO

Magnetic skyrmions are topologically nontrivial particles with a potential application as information elements in future spintronic device architectures. While they are commonly portrayed as two dimensional objects, in reality magnetic skyrmions are thought to exist as elongated, tube-like objects extending through the thickness of the host material. The study of this skyrmion tube state (SkT) is vital for furthering the understanding of skyrmion formation and dynamics for future applications. However, direct experimental imaging of skyrmion tubes has yet to be reported. Here, we demonstrate the real-space observation of skyrmion tubes in a lamella of FeGe using resonant magnetic x-ray imaging and comparative micromagnetic simulations, confirming their extended structure. The formation of these structures at the edge of the sample highlights the importance of confinement and edge effects in the stabilisation of the SkT state, opening the door to further investigation into this unexplored dimension of the skyrmion spin texture.

2.
J Visc Surg ; 157(6): 461-467, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32146147

RESUMO

BACKGROUND: In the last two decades, intraperitoneal(IP) chemotherapy during surgery achieved recognition in the management of peritoneal metastases. Occupational hazard became a concern leading to standardized safety measures. The aim of this study is to evaluate the perceived level of information and protection among the non-medical caregivers involved in HIPEC and PIPAC in a high-volume center. METHODS: All non-medical caregivers in the operating theatre of our institution were asked to answer a questionnaire between April and May 2018. The questionnaire included multiple choice questions and open questions structured in four parts: demographic variables, perceived level of information, perceived level of protection, interest in further education. RESULTS: Forty-nine caregivers agreed to answer the questionnaire. All identified IP chemotherapy as an occupational risk. Thirty-eight persons (77.55%) trusted the protective value of safety measures during HIPEC compared to 32 (65.3%) during PIPAC. A total of 29 persons (59.18%) used some of the measures while 16 (32.65%) used all of them. Main reasons of non-use were slips and lapses (7 persons) and lack of comfort (4 persons). A total of 34 caregivers considered the level of information about safety protocols as good or very good (69%). A total of 46 persons considered the level of protection as satisfying or excellent (93.87%). A total of 36 (73.47%) interviewees expressed the need of receiving more information. CONCLUSIONS: The present study shows that non-medical caregivers in the operating theatres are aware of the occupational hazards related to the use of IP chemotherapy. The use of protective measures is associated with decreased level of perceived risk. However there is a high need of continuous education on this subject for the involved personnel.


Assuntos
Pessoal Técnico de Saúde , Antineoplásicos/intoxicação , Quimioterapia do Câncer por Perfusão Regional/métodos , Hipertermia Induzida/métodos , Exposição Ocupacional/efeitos adversos , Salas Cirúrgicas , Neoplasias Peritoneais/tratamento farmacológico , Gestão da Segurança , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Peritoneais/secundário , Equipamento de Proteção Individual , Inquéritos e Questionários
3.
J Synchrotron Radiat ; 26(Pt 1): 280-290, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30655496

RESUMO

A new instrument named COMET for COherent Magnetic scattering Experiments in Transmission using polarized soft X-rays has been designed and built. This high-vacuum setup is placed at the intermediate focal point of the elastic branch of the SEXTANTS beamline at Synchrotron SOLEIL. The main application is in solid state physics, the instrument being optimized for studying material properties using coherent scattering of soft X-rays with an emphasis on imaging, with chemical selectivity, the magnetic domains of artificially nano-structured materials. The instrument's principal features are presented and illustrated through recently performed experiments.

4.
Sci Rep ; 6: 36307, 2016 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-27796347

RESUMO

The magnetisation dynamics of the vortex core and Landau pattern of magnetic thin-film elements has been studied using holography with extended reference autocorrelation by linear differential operator (HERALDO). Here we present the first time-resolved x-ray measurements using this technique and investigate the structure and dynamics of the domain walls after excitation with nanosecond pulsed magnetic fields. It is shown that the average magnetisation of the domain walls has a perpendicular component that can change dynamically depending on the parameters of the pulsed excitation. In particular, we demonstrate the formation of wave bullet-like excitations, which are generated in the domain walls and can propagate inside them during the cyclic motion of the vortex core. Based on numerical simulations we also show that, besides the core, there are four singularities formed at the corners of the pattern. The polarisation of these singularities has a direct relation to the vortex core, and can be switched dynamically by the wave bullets excited with a magnetic pulse of specific parameters. The subsequent dynamics of the Landau pattern is dependent on the particular configuration of the polarisations of the core and the singularities.

5.
J Med Life ; 8(3): 258-62, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26351523

RESUMO

BACKGROUND AND AIM: Non-alcoholic fatty liver disease (NAFLD) is the most common cause of liver disease worldwide, with a prevalence of 20%-40% in Western populations. The purpose of this article is to review data related to lifestyle changes in patients with NAFLD. METHOD: We searched a public domain database (PubMed) with the following categories: disease (NAFLD, fatty liver, and non-alcoholic steatohepatitis [NASH]) and intervention (lifestyle intervention, diet, nutrition) with each possible combination through 25 September 2014, for relevant articles. Review of articles was restricted to those published in English. We selected the studies involving adult patients only. CONCLUSION: There is no consensus as to what diet or lifestyle approach is the best for NAFLD patients. However, patients with NAFLD may benefit from a moderate- to low-carbohydrate (40%-45% of total calories) diet, coupled with increased dietary MUFA and n-3 PUFAs, reduced SFAs. More CRT are needed to clarify the specific effects of different diets and dietary components on the health of NAFLD patients. ABBREVIATIONS: NAFL = Non-alcoholic fatty liver, NAFLD = non-alcoholic fatty liver disease, NASH = non-alcoholic steatohepatitis, HCC = hepatocarcinoma, BEE = basal energy expenditure, CRT = A small clinical randomized trial showed that short-term carbohydrate restriction is more efficacious in reducing intrahepatic triglyceride, IHT = intrahepatic triglyceride, VLCD = Very low calorie diets, AST = aspartate aminotransferases, SFAs = saturated fatty acids.


Assuntos
Hepatopatia Gordurosa não Alcoólica/dietoterapia , Terapia Nutricional , Carboidratos da Dieta/uso terapêutico , Fibras na Dieta , Proteínas Alimentares/uso terapêutico , Ingestão de Energia , Humanos
6.
Phys Rev Lett ; 113(24): 247202, 2014 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-25541801

RESUMO

Thin film magnetization reversal without applying external fields is an attractive perspective for applications in sensors and devices. One way to accomplish it is by fine-tuning the microstructure of a magnetic substrate via temperature control, as in the case of a thin Fe layer deposited on a MnAs/GaAs(001) template. This work reports a time-resolved resonant scattering study exploring the magnetic and structural properties of the Fe/MnAs system, using a 100 fs optical laser pulse to trigger local temperature variations and a 100 fs x-ray free-electron laser pulse to probe the induced magnetic and structural dynamics. The experiment provides direct evidence that a single optical laser pulse can reverse the Fe magnetization locally. It reveals that the time scale of the magnetization reversal is slower than that of the MnAs structural transformations triggered by the optical pulse, which take place after a few picoseconds already.

7.
Curr Health Sci J ; 39(4): 232-6, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24778863

RESUMO

THE PURPOSE OF THIS STUDY WAS THE QUALITATIVE AND QUANTITATIVE ANALYSIS OF FLAVONOIDS FROM ROBINIA PSEUDOACACIA USING TWO DIFFERENT TECHNIQUES OF ANALYSIS: Thin Layer Chromatography (TLC) and TLC coupled with photo-densitometry. The results obtained by chromatographic analysis showed a higher concentration of flavonoids in flowers than in leaves. The flowers harvested in the plains have a higher concentration of hyperoside (0.9 mg/mL) compared with the flowers collected from the hills (0.54 mg/mL). The leaves are richer in ruthoside (0.98 mg/mL) compared with the flowers.

8.
Chirurgia (Bucur) ; 105(3): 331-7, 2010.
Artigo em Romano | MEDLINE | ID: mdl-20726298

RESUMO

INTRODUCTION: Transabdominal routes for surgery entail general anaesthesia with its inherent risks and complications (prolonged hospital stay, abdominal incisions that may be difficult in obese patients). Minimally invasive procedures require shorter hospitalization, have shorter recovery periods, less postoperative discomfort, and lower morbidity and complications. The purpose of this study was to use a porcine model to determine the feasibility and the safety of organ resection (oophorectomy and tubectomy). MATERIALS AND METHODS: 10 Big White pigs between 25-30 kg underwent transgastric ooforectomy. The first 5 cases were performed in a hybrid procedure (laparoscopic-NOTES) in order to have a better control and supervise the maneuvers done by the mobile endoscope and to guide in the abdominal cavity. RESULTS: Adnexectomy was possible in all ten experiments. Full operative time (from starting endoscopy to complete gastrectomy closing) was 180 min to 270 min. The gastric defect closing was the most difficult manoever lasting from 10 min with OTSC clips to 100 using endoloops and clips. The animals have tolerated well the experiments and there have been no remarkable incidents during our 10 experments. In only one case a bleeding from gastotomy required electric coagulation. CONCLUSION: Transgastric ooforectomy in an experimental model is a procedure that requires advanced laparoscopical and endoscopical skills. Our early results are promissing. Its application in humans needs further confirmation of the method.


Assuntos
Gastroscopia , Ovariectomia/métodos , Estômago/cirurgia , Animais , Modelos Animais de Doenças , Tubas Uterinas/cirurgia , Estudos de Viabilidade , Feminino , Análise de Sobrevida , Sus scrofa , Suínos , Fatores de Tempo
9.
Chirurgia (Bucur) ; 105(2): 177-86, 2010.
Artigo em Romano | MEDLINE | ID: mdl-20540229

RESUMO

INTRODUCTION: Initially considered experimental, liver transplantation (LT) has become the treatment of choice for the patients with end-stage liver diseases. MATERIAL AND METHODS: Between April 2000 and October 2009, 200 LTs (10 reLTs) were performed in 190 patients, this study being retrospective. There were transplanted 110 men and 80 women, 159 adults and 31 children with the age between 1 and 64 years old (mean age--39.9). The main indication in the adult group was represented by viral cirrhosis, while the pediatric series the etiology was mainly glycogenosis and biliary atresia. There were performed 143 whole graft LTs, 46 living donor LTs, 6 split LTs, 4 reduced LTs and one domino LT RESULTS: The postoperative survival was 90% (170 patients). The patient and graft one-year and five-year survivals were 76.9%, 73.6% and 71%, 68.2%, respectively. The early complications occurred in 127 patients (67%). The late complications were recorded in 71 patients (37.3%). The intraoperative and early postoperative mortality rate was 9.5% (18 patients). CONCLUSIONS: The Romanian liver transplantation program from Fundeni includes all types of current surgical techniques and the results are comparable with those from other international centers.


Assuntos
Cirrose Hepática/cirurgia , Transplante de Fígado/métodos , Adolescente , Adulto , Atresia Biliar/cirurgia , Criança , Pré-Escolar , Feminino , Doença de Depósito de Glicogênio/cirurgia , Humanos , Lactente , Cirrose Hepática/patologia , Cirrose Hepática/virologia , Hepatopatias/cirurgia , Transplante de Fígado/efeitos adversos , Transplante de Fígado/mortalidade , Doadores Vivos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Romênia/epidemiologia , Taxa de Sobrevida
10.
Phys Rev Lett ; 101(10): 105002, 2008 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-18851220

RESUMO

A gamma-ray source with an intense component around the giant dipole resonance for photonuclear absorption has been obtained via bremsstrahlung of electron bunches driven by a 10-TW tabletop laser. 3D particle-in-cell simulation proves the achievement of a nonlinear regime leading to efficient acceleration of several sequential electron bunches per each laser pulse. The rate of the gamma-ray yield in the giant dipole resonance region (8

11.
Phys Rev Lett ; 99(18): 185002, 2007 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-17995415

RESUMO

We report on simultaneous measurements of backward- and forward-accelerated protons spectra when an ultrahigh intensity (approximately 5 x 10(18) W/cm(20), ultrahigh contrast (>10(10)) laser pulse interacts with foils of thickness ranging from 0.08 to 105 microm. Under such conditions, free of preplasma originating from ionization of the laser-irradiated surface, we show that the maximum proton energies are proportional to the p component of the laser electric field only and not to the ponderomotive force and that the characteristics of the proton beams originating from both target sides are almost identical. All these points have been corroborated by extensive 1D and 2D particle-in-cell simulations showing a very good agreement with the experimental data.

12.
Phys Rev Lett ; 94(4): 045004, 2005 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-15783566

RESUMO

The comparative efficiency and beam characteristics of high-energy ions generated by high-intensity short-pulse lasers (approximately 1-6 x 10(19) W/cm2) from both the front and rear surfaces of thin metal foils have been measured under identical conditions. Using direct beam measurements and nuclear activation techniques, we find that rear-surface acceleration produces higher energy particles with smaller divergence and a higher efficiency than front-surface acceleration. Our observations are well reproduced by realistic particle-in-cell simulations, and we predict optimal criteria for future applications.

13.
Phys Rev Lett ; 91(10): 105001, 2003 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-14525484

RESUMO

The second harmonic of the laser light (2omega(0)) is observed on the rear side of thick solid targets irradiated by a laser beam at relativistic intensities. This emission is explained by the acceleration by the laser pulse in front of the target of short bunches of electrons separated by the period (or half the period) of the laser light. When reaching the rear side of the target, these electron bunches emit coherent transition radiation at 2omega(0). The observations indicate that, in our conditions, the minimum fraction of the laser energy transferred to these electron bunches is of the order of 1%.

20.
Endocrinologie ; 25(1): 45-53, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-2883720

RESUMO

The morphotype of 40 children with cryptorchidism (18 bilateral, 22 unilateral), selected by complex endocrine examination, was assessed in relation to age and clinical form of cryptorchidism. The morphotype was established on the basis of 9 anthropometric parameters (weight, stature, pube-ground distance, a-a, thr-thr, thoracic, abdominal, hips and cephalic circumferences). The malformed lot consists of 28 children with common and 12 with symptome cryptorchidism (5 adiposogenital, 3 male Turner's syndrome and 3 with gonadal dysgenesis). In the child with symptom cryptorchidism, the morphogram reveals, irrespective of age, a morphotype which corresponds in point of absolute dimensions and proportions, to the somatotype in which cryptorchidism as a symptome is included. The child with common cryptorchidism has irrespective of age, a normal or short stature and is underweight. Compared to the stature, the head is small, the lower limbs are short, the trunk is long and the hips are well developed. In our series of common cryptorchid child, the most marked statural deficit was found between 11 and 15 years as well as under the age of 6.


Assuntos
Constituição Corporal , Criptorquidismo/patologia , Disgenesia Gonadal/patologia , Humanos , Hipogonadismo/patologia , Doenças Hipotalâmicas/patologia , Masculino , Síndrome de Noonan/patologia , Obesidade/patologia , Síndrome
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