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1.
J Synchrotron Radiat ; 26(Pt 1): 280-290, 2019 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-30655496

RESUMEN

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.

2.
Phys Rev Lett ; 113(24): 247202, 2014 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-25541801

RESUMEN

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.

3.
Chirurgia (Bucur) ; 105(3): 331-7, 2010.
Artículo en Ro | MEDLINE | ID: mdl-20726298

RESUMEN

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.


Asunto(s)
Gastroscopía , Ovariectomía/métodos , Estómago/cirugía , Animales , Modelos Animales de Enfermedad , Trompas Uterinas/cirugía , Estudios de Factibilidad , Femenino , Análisis de Supervivencia , Sus scrofa , Porcinos , Factores de Tiempo
4.
Chirurgia (Bucur) ; 105(2): 177-86, 2010.
Artículo en Ro | MEDLINE | ID: mdl-20540229

RESUMEN

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.


Asunto(s)
Cirrosis Hepática/cirugía , Trasplante de Hígado/métodos , Adolescente , Adulto , Atresia Biliar/cirugía , Niño , Preescolar , Femenino , Enfermedad del Almacenamiento de Glucógeno/cirugía , Humanos , Lactante , Cirrosis Hepática/patología , Cirrosis Hepática/virología , Hepatopatías/cirugía , Trasplante de Hígado/efectos adversos , Trasplante de Hígado/mortalidad , Donadores Vivos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Rumanía/epidemiología , Tasa de Supervivencia
5.
J Visc Surg ; 157(6): 461-467, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32146147

RESUMEN

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.


Asunto(s)
Técnicos Medios en Salud , Antineoplásicos/envenenamiento , Quimioterapia del Cáncer por Perfusión Regional/métodos , Hipertermia Inducida/métodos , Exposición Profesional/efectos adversos , Quirófanos , Neoplasias Peritoneales/tratamiento farmacológico , Administración de la Seguridad , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Peritoneales/secundario , Equipo de Protección Personal , Encuestas y Cuestionarios
6.
Nat Commun ; 11(1): 1726, 2020 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-32265449

RESUMEN

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.

7.
Sci Rep ; 6: 36307, 2016 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-27796347

RESUMEN

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.

8.
J Med Life ; 8(3): 258-62, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26351523

RESUMEN

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.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico/dietoterapia , Terapia Nutricional , Carbohidratos de la Dieta/uso terapéutico , Fibras de la Dieta , Proteínas en la Dieta/uso terapéutico , Ingestión de Energía , Humanos
9.
Arch Environ Health ; 34(6): 461-3, 1979.
Artículo en Inglés | MEDLINE | ID: mdl-518128

RESUMEN

The incidence of chromosome aberrations was studied by peripheral blood incubation (52 hr, the last 4 hr in the presence of Colcemid) using a modification of the Evans' technique in twenty-two men exposed to either vapors of metallic mercury (Group I) or organic mercury (Group II). Mercury concentrations of the work areas frequently exceeded the Maximum Allowable Concentrations in the past. During the year proceding the investigation, mercury values ranged between 0.15 and 0.44 mg/m3. None of the investigated men were poisoned, but all had had repeated increased mercury absorption with urinary eliminations reaching 890 microgram/l and 896 microgram/l for subjects in Groups I and II, respectively. The incidence of chromosome aberrations was significantly higher (P less than .001) in subjects exposed to mercury as compared with a control group (ten subjects) of a similar mean age. There was no statistical difference in the incidence of chromosome aberrations between men belonging to Groups I and II. Although an increase of both chromatid gaps and breaks was noticed in exposed men, the incidence did not significantly differ from controls. No chromatid interchanges were recorded and no difference between exposed and control subjects was noticed concerning the frequency of aneuploid or polyploid cells.


Asunto(s)
Aberraciones Cromosómicas , Mercurio/efectos adversos , Medicina del Trabajo , Adulto , Humanos , Masculino , Persona de Mediana Edad
10.
Arch Environ Health ; 30(8): 396-401, 1975 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1155972

RESUMEN

The reproductive ability of 150 men occupationally exposed to lead were studied by clinical and toxicological analysis. Subjects were divided into four groups: lead-poisoned workmen (23) and those showing a moderate (42), slight (35), or physiologic absorption (50). Findings show that (1) Lead poisoning as well as moderate increased absorption of lead decrease the fertile ability of men. An increased frequency of asthenospermia, hypospermia, and teratospermia have objectified the decrease. (2) Slight increased or physiologic absorption of lead do not significantly influence the fertile ability of workmen. (3) Hypofertility induced by lead is due, perhaps, to its direct toxic effect on the gonads, as no interference with the hypothalamopituitary axis were evidenced.


Asunto(s)
Plomo/farmacología , Reproducción/efectos de los fármacos , Adulto , Consumo de Bebidas Alcohólicas , Relación Dosis-Respuesta a Droga , Eyaculación/efectos de los fármacos , Exposición a Riesgos Ambientales , Humanos , Sistema Hipotálamo-Hipofisario/efectos de los fármacos , Plomo/sangre , Plomo/orina , Libido/efectos de los fármacos , Masculino , Oligospermia/inducido químicamente , Orgasmo/efectos de los fármacos , Enfermedades del Pene/inducido químicamente , Conducta Sexual/efectos de los fármacos , Fumar/complicaciones , Espermatozoides/efectos de los fármacos , Testículo/efectos de los fármacos
11.
Curr Health Sci J ; 39(4): 232-6, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24778863

RESUMEN

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.

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