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1.
Nano Lett ; 24(18): 5536-5542, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38657957

RESUMO

Electro-optic metasurfaces have demonstrated significant potential in enhancing the modulation speed and efficiency for fast and large-scale free-space optical devices. Barium titanate has a strong electro-optic Pockels coefficient, but its availability in thin-film form is restricted due to costly growth processes or low thickness. Here, we fabricated active metasurfaces using an etch-free bottom-up process with sol-gel-based polycrystalline barium titanate with a large electro-optic coefficient similar to bulk lithium niobate. We achieve strong hybrid Mie/surface lattice resonances with a quality-factor of 200 at 633 nm wavelength, enhancing the light-matter interaction and therefore the Pockels effect. The metasurface transmission is electro-optically modulated with up to 5 MHz driving frequency at low voltages of less than 1 V thanks to resonant enhancement of the modulation amplitude by 2 orders of magnitude. This successful demonstration of electro-optic modulation in nanoimprinted barium titanate structures paves the way for low-cost and large-scale free-space modulators or tunable metalenses.

2.
Nanoscale ; 14(24): 8858-8864, 2022 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-35697049

RESUMO

We present a wearable device with III-V nanowires in a flexible polymer, which is used for active mechanical tuning of the second-harmonic generation intensity. An array of vertical GaAs nanowires was grown with metalorganic vapour-phase epitaxy, then embedded in polydimethylsiloxane and detached from the rigid substrate with mechanical peel off. Experimental results show a tunability of the second-harmonic generation intensity by a factor of two for 30% stretching which matches the simulations including the distribution of sizes. We studied the impact of different parameters on the band dispersion and tunability of the second-harmonic generation, such as the pitch, the length, and the diameter. We predict at least three orders of magnitude active mechanical tuning of the nonlinear signal intensity for nanowire arrays. The flexibility of the array together with the resonant wavelength engineering make such structures perspective platforms for future bendable or stretchable nanophotonic devices as light sources or sensors.

3.
J Biol Regul Homeost Agents ; 33(5 Suppl. 1): 39-44. Special Issue: Focus on Pediatric Nephrology, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31630712

RESUMO

Urolithiasis is a well-known condition that can affect any part of the urinary tract. With a rate of 3-5% the incidence of upper urinary tract for long has been higher in adults (1-3), but recently it has increased among children reaching 3,3% . Indeed, more than 1% of all urinary stones are seen in patients aged less than 18 years (4). Pediatric urolithiasis is endemic in Turkey and Far East and it is probably due to malnutrition and racial factors (5). The spontaneous stone passage is more likely in children than in adults, indeed ureteral calculi spontaneously pass into 41-63% of children (1). Rate of stone passage depends on size and stone location in the urinary system. Stones sized less than 5 mm have a passage rate ranging from 40% to 98%, whilst stones > 5 mm have between 55% and 50% (6). In the last decade, the use of alpha blockers has proven well efficacious in helping spontaneous passage of distal ureteric stones in adults (7-9). The latest EAU guidelines support their use in adults while remain vague about their use in children because of unclear safety and efficacy (4). In search of evidence supporting or not the use of medical expulsive therapy in children we reviewed the literature dealing with the management of urolithiasis in pediatric patients. The primary aim of the present study was to evaluate the efficacy of medical expulsive therapy (MET), defined as stone expulsion rate, with a-blockers compared to a control group. The secondary aim was to assess the safety, defined as side effects rate, of MET compared to a control group.


Assuntos
Cálculos Ureterais/terapia , Urolitíase/terapia , Antagonistas Adrenérgicos alfa/uso terapêutico , Criança , Pré-Escolar , Humanos
4.
J Biol Regul Homeost Agents ; 33(5 Suppl. 1): 87-89. Special Issue: Focus on Pediatric Nephrology, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31630720

RESUMO

End-stage renal diseases requiring chronic dialysis are rare in childhood and adolescence, but they are associated with high mortality and impaired quality of life (1, 2). The most common disease that causes chronic kidney disease (CKD) is primary glomerular disease (GD), followed by congenital abnormalities of the kidney and urinary tract, cystic, hereditary or congenital disorders and, more rarely, secondary GD. However, patients with secondary GD, urologic disorders, and metabolic diseases have greater mortality risk than patients with primary GD (3). Here, we focused on the different options of treatment available, and specifically we compared peritoneal dialysis and hemodialysis, showing pros and cons between them.


Assuntos
Falência Renal Crônica/terapia , Diálise Peritoneal , Diálise Renal , Adolescente , Criança , Humanos , Falência Renal Crônica/mortalidade , Qualidade de Vida
5.
G Chir ; 37(4): 167-170, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27938534

RESUMO

Acute chylous peritonitis is defined as the onset of acute abdomen findings due to abrupt chylous fluid accumulation in the peritoneal space. A correct diagnosis of this condition is seldom made preoperatively. The optimal management of true chylous pancreatitis depends upon the underlying etiology. Thorough lavage of the abdomen and adequate drainage has proven to be an excellent treatment modality for acute chylous peritonitis, since resolution of chylous ascites usually occurs within the next few days. However, conservative treatment may be appropriate in selected cases. We present a case report and a brief review of the literature.


Assuntos
Ascite Quilosa/complicações , Ascite Quilosa/terapia , Drenagem , Pancreatite/complicações , Pancreatite/terapia , Irrigação Terapêutica , Dor Abdominal/etiologia , Adulto , Ascite Quilosa/diagnóstico , Drenagem/métodos , Feminino , Humanos , Náusea/etiologia , Pancreatite/diagnóstico , Irrigação Terapêutica/métodos , Resultado do Tratamento , Vômito/etiologia
6.
Neuroimage ; 91: 109-19, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24287441

RESUMO

Explicit negative attitudes and blameful beliefs (e.g. poor diet, laziness) towards obese individuals are well documented and are pervasive even among health professionals. Here we sought to determine whether obesity stigma is reflected in a fundamental feature of intersubjectivity namely the automatic neural resonance with others' affective experiences. During fMRI, normal-weight female participants observed short clips depicting normal-weight (NW) and obese (Ob) models experiencing pain. Importantly, participants believed that half of the Ob were overweight due to a hormonal disorder (HormOb) and ignored the cause of obesity of the remaining models (Unknown obese models; UnkOb). Analyses of hemodynamic responses showed reduced activity to the pain of Ob compared to that of NW in areas associated with pain processing and early visual processing. The comparison between the two Ob conditions revealed a further decrease of activity to HormOb's pain compared to UnkOb's (and NW) pain in the right inferior frontal gyrus, an area associated with emotional resonance. Our study demonstrates that stigma for obese individuals can be observed at implicit levels, and that it is modulated by knowledge concerning the etiology of obesity, with the seemingly surprising result that obesity due to disease may result in greater stigmatization. Moreover, the perceived similarity with the models and the ambivalent emotion of pity may index biased brain responses to obese individuals' pain. The study highlights a possibly important neural link between resonance with the pain of others and obesity stigma.


Assuntos
Obesidade/psicologia , Estereotipagem , Índice de Massa Corporal , Mapeamento Encefálico , Córtex Cerebral/anatomia & histologia , Córtex Cerebral/fisiologia , Circulação Cerebrovascular , Síndrome de Cushing/complicações , Imagem Ecoplanar , Empatia/fisiologia , Face , Expressão Facial , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Motivação/fisiologia , Obesidade/etiologia , Dor/psicologia , Medição da Dor , Estimulação Luminosa , Reflexo Pupilar/fisiologia , Percepção Social , Adulto Jovem
7.
Science ; 341(6150): 1062, 2013 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-24009374
8.
Neurocrit Care ; 2(3): 325-9, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16159084

RESUMO

Rifampin, a protein synthesis inhibitor, reduced mortality in a mouse model of meningitis compared to bacteriolytic cephalosporin standard therapy. To assess whether moxifloxacin (known to cause a less rapid bacteriolysis than cephalosporins) can similarly reduce mortality, mice infected with Streptococcus pneumoniae by deep intracerebral injection were treated subcutaneously with either 200 mg/kg of moxifloxacin or ceftriaxone every 8 hours for 5 days (n = 49 each). They were then observed for an additional 8 days. Overall mortalities were 35 and 29 in moxifloxacin- and ceftriaxone-treated mice, respectively (p = 0.29). Kaplan-Meier survival analysis also revealed no statistically significant differences (p = 0.32). Moxifloxacin failed to reduce mortality compared to cephalosporin standard therapy.


Assuntos
Antibacterianos/uso terapêutico , Compostos Aza/uso terapêutico , Ceftriaxona/uso terapêutico , Meningite Pneumocócica/tratamento farmacológico , Quinolinas/uso terapêutico , Animais , Antibacterianos/administração & dosagem , Antibacterianos/farmacocinética , Compostos Aza/administração & dosagem , Compostos Aza/farmacocinética , Ceftriaxona/administração & dosagem , Ceftriaxona/farmacocinética , Modelos Animais de Doenças , Esquema de Medicação , Fluoroquinolonas , Injeções Subcutâneas , Masculino , Meningite Pneumocócica/mortalidade , Meningite Pneumocócica/patologia , Camundongos , Camundongos Endogâmicos C57BL , Moxifloxacina , Quinolinas/administração & dosagem , Quinolinas/farmacocinética , Resultado do Tratamento
9.
Phys Rev Lett ; 93(13): 132701, 2004 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-15524714

RESUMO

Breakup densities of hot 197Au-like residues have been deduced from the systematic trends of Coulomb parameters required to fit intermediate-mass-fragment kinetic-energy spectra. The results indicate emission from nuclei near normal nuclear density below an excitation energy E(*)/A less, similar 2 MeV, followed by a gradual decrease to a near-constant value of rho/rho(0) approximately 0.3 for E(*)/A greater, similar 5 MeV. Temperatures derived from these data with a density-dependent Fermi-gas model yield a nuclear caloric curve that is generally consistent with those derived from isotope ratios.

10.
Phys Rev Lett ; 92(6): 062701, 2004 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-14995234

RESUMO

Using symmetric 112Sn+112Sn, 124Sn+124Sn collisions as references, we probe isospin diffusion in peripheral asymmetric 112Sn+124Sn, 124Sn+112Sn systems at an incident energy of E/A=50 MeV. Isoscaling analyses imply that the quasiprojectile and quasitarget in these collisions do not achieve isospin equilibrium, permitting an assessment of isospin transport rates. We find that comparisons between isospin sensitive experimental and theoretical observables, using suitably chosen scaled ratios, permit investigation of the density dependence of the asymmetry term of the nuclear equation of state.

11.
Phys Rev Lett ; 88(2): 022701, 2002 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-11801007

RESUMO

A percolation model of nuclear fragmentation is used to interpret 10.2 GeV/c p+197Au multifragmentation data. Emphasis is put on finding signatures of a continuous nuclear matter phase transition in finite nuclear systems. Based on model calculations, corrections accounting for physical constraints of the fragment detection and sequential decay processes are derived. Strong circumstantial evidence for a continuous phase transition is found, and the values of two critical exponents, sigma = 0.5+/-0.1 and tau = 2.35+/-0.05, are extracted from the data. A critical temperature of T(c) = 8.3+/-0.2 MeV is found.

12.
Phys Rev Lett ; 88(4): 042701, 2002 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-11801117

RESUMO

The thermal component of the 8 GeV/c pi+ Au data of the ISiS Collaboration is shown to follow the scaling predicted by Fisher's model when Coulomb energy is taken into account. Critical exponents tau and sigma, the critical point (p(c),rho(c),T(c)), surface energy coefficient c(0), enthalpy of evaporation DeltaH, and critical compressibility factor C(F)(c) are determined. For the first time, the experimental phase diagrams, (p,T) and (T,rho), describing the liquid vapor coexistence of finite neutral nuclear matter have been constructed.

13.
Phys Rev Lett ; 84(26 Pt 1): 5971-4, 2000 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-10991101

RESUMO

Excitation-energy-gated two-fragment correlation functions have been studied between E(*)/A = (2-9)A MeV for equilibriumlike sources formed in 8-10 GeV/c pi(-) and p+197Au reactions. Comparison with an N-body Coulomb-trajectory code shows an order of magnitude decrease in the fragment emission time in the interval E(*)/A = (2-5)A MeV, followed by a nearly constant breakup time at higher excitation energy. The decrease in emission time is strongly correlated with the onset of multifragmentation and thermally induced radial expansion, consistent with a transition from surface-dominated to bulk emission expected for spinodal decomposition.

14.
G Chir ; 21(5): 239-41, 2000 May.
Artigo em Italiano | MEDLINE | ID: mdl-10862460

RESUMO

The Authors report the case of a male patient, 52 year old, suffering from retroperitoneal leiomyosarcoma, submitted to multiple operations in the space of about seven years, for the presence of liver metastases and local relapses; the good general health state, the moderate grade of the neoplasm and the disease's fair interval free, have justified the therapeutic attitude adopted; the patient at present enjoys good health.


Assuntos
Leiomiossarcoma/cirurgia , Recidiva Local de Neoplasia/cirurgia , Neoplasias Retroperitoneais/cirurgia , Humanos , Leiomiossarcoma/secundário , Masculino , Pessoa de Meia-Idade , Neoplasias Retroperitoneais/patologia
15.
Minerva Urol Nefrol ; 50(2): 121-5, 1998 Jun.
Artigo em Italiano | MEDLINE | ID: mdl-9707966

RESUMO

BACKGROUND AND AIMS: The scarce availability of organs and the excellent results obtained using living donors, due to the improved degree of compatibility between donor and recipient, the short period of organ storage and the possibility of choosing the ideal surgical "timing", in the authors' opinion justify the use of living donors from a clinical and ethical-moral point of view. METHODS: Between April 1986 and December 1996 a 406 renal transplants were performed; of these, 10 patients received grafts from living donors. Preliminary screening consisted in a careful clinical and immunological evaluation to evaluate the operating risk, good compatibility with the recipient and the perfect bilateral function of the kidney. RESULTS: The 10 donors had no postoperative mortality or morbidity, no alterations of renal function, and no onset of hypertension and/or proteinuria in the immediate post-operative period or at a distance. The organ and patient survival rate (including a follow-up of between 2 and 54 months, mean 25 months) was 100%. CONCLUSIONS: The authors suggest that living donors represent a valid alternative in uremic patients. This therapeutic act must be carried out in complete respect for ethical, moral and legislative principles and must be based on a careful clinical selection to minimise the risks of donation and to guarantee the maximum benefit for the recipient. It is to be hoped that further improvements are made in immunodepressive treatment, and above all an appropriate increase in transplants from cadaveric donors, making the use of living donors superfluous since this practice maims a perfectly healthy individual.


Assuntos
Falência Renal Crônica/cirurgia , Transplante de Rim/métodos , Doadores de Tecidos , Animais , Humanos , Uremia/cirurgia
16.
Minerva Urol Nefrol ; 50(2): 127-31, 1998 Jun.
Artigo em Italiano | MEDLINE | ID: mdl-9707967

RESUMO

BACKGROUND: The incidence of malignancies after transplantation is higher when compared with expected cancer in control patients, particularly skin and female genital cancer, non-Hodgkin's disease and Kaposi's sarcoma. The aim of this study is to evaluate the frequency and the efficacy of the treatment of cancer following renal transplantation. METHODS: A retrospective analysis of 404 recipients was performed and it showed the onset of 15 cancers (8 skin cancers, 3 Kaposi's sarcomas, 2 renal carcinomas, 1 urotelioma and 1 colon cancer) in 11 patients (3.7%). At the time of diagnosis, the mean period of immunosuppressive therapy (7 cases of double therapy, 4 cases of triple therapy) was 44.8 months. Skin cancer (53.3%) and Kaposi's sarcoma (20%) were the most frequent in personal experience as reported in literature. Neither lymphomas, nor female genital cancers were detected. RESULTS: All the cases were surgically treated, except patients with Kaposi's sarcoma, whose immunosuppressive therapy was reduced without alteration of renal function. Death-rate was 0.25% (1 case), the remaining patients show no signs of local recurrence or metastasis with preserved renal function except for the patient with renal carcinoma of the transplanted kidney, who underwent nephrectomy and returned in replacement therapy. CONCLUSIONS: The conclusion is drawn that the research of relationship between type of immunosuppressive therapy and cancer incidence and careful clinical and instrumental examination of transplant patients may contribute to reduce the onset of neoplastic degenerations and lead to an early diagnosis.


Assuntos
Transplante de Rim , Neoplasias/etiologia , Antineoplásicos/uso terapêutico , Feminino , Humanos , Imunossupressores/uso terapêutico , Neoplasias Renais/etiologia , Neoplasias Renais/terapia , Masculino , Pessoa de Meia-Idade , Neoplasias/imunologia , Neoplasias/terapia , Complicações Pós-Operatórias , Estudos Retrospectivos , Sarcoma de Kaposi/etiologia , Sarcoma de Kaposi/imunologia , Sarcoma de Kaposi/terapia , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/terapia
17.
G Chir ; 16(1-2): 36-42, 1995.
Artigo em Italiano | MEDLINE | ID: mdl-7779628

RESUMO

The authors report their experience with hiatus hernia surgery (9 cases of large hernia with severe gastroesophageal reflux). The fundamental role of instrumental diagnostics in establishing both a clear indication for surgical correction and the quality of the results obtained is emphasized. Technical details of the surgical treatment are report as well. On the basis of their experience and in accordance with other authors the Nissen fundoplication is considered a valid antireflux procedure. Furthermore, the abdominal approach used for this procedure allows to treat other abdominal pathologies often associated with hiatal hernia.


Assuntos
Hérnia Hiatal/cirurgia , Feminino , Seguimentos , Fundoplicatura/métodos , Refluxo Gastroesofágico/diagnóstico , Refluxo Gastroesofágico/cirurgia , Gastroscopia , Hérnia Hiatal/diagnóstico , Humanos , Masculino , Radiografia , Estômago/diagnóstico por imagem
18.
Angiology ; 45(2): 95-100, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8129196

RESUMO

UNLABELLED: To assess the role of transesophageal pacing (TP) at very high rates in the follow-up of patients with recurrent and sustained paroxysmal atrial fibrillation (AF) on therapy, the authors studied 15 patients (10 women, 5 men; aged forty-four to seventy-seven years old). Of them only 1 had a mild mitral regurgitation; none had hyperthyroidism or acute ischemic heart disease. They tested propafenone (P) at a dose of 1.4-2 mg/kg over ten minutes as an intravenous bolus and 0.5 mg/minute as intravenous maintenance for two hours and then 300 mg twice daily orally and chronically. Serial TPs at very rapid rates (up to 600 bpm) were performed to test the long-term efficacy of P to prevent paroxysmal AF. The mean follow-up was fifteen months (nine to twenty-four months). RESULTS: Intravenous P converted AF in five to ninety minutes (mean twenty-one minutes) in 9/15 patients (conversion rate of 60%); in an additional 4 patients oral P converted AF in two to fifteen hours. In the other 2 patients P failed to convert AF. Three patients experienced recurrence of AF in the early follow-up. Of the 10 patients who completed the entire protocol, only 1, who had mild mitral prolapse regurgitation and AF induction by TP, experienced new episodes of AF during follow-up. No significant side effects were noted during P therapy. CONCLUSIONS: Propafenone appears safe and effective for controlling and preventing recurrent and sustained AF. Transesophageal pacing is a valid tool for predicting the efficacy of long-term therapy in the follow-up of patients with paroxysmal atrial fibrillation.


Assuntos
Fibrilação Atrial/diagnóstico , Estimulação Cardíaca Artificial , Propafenona/uso terapêutico , Administração Oral , Adulto , Idoso , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/prevenção & controle , Estimulação Cardíaca Artificial/métodos , Ecocardiografia Doppler , Feminino , Seguimentos , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Propafenona/administração & dosagem , Recidiva
19.
Chir Ital ; 45(1-6): 53-72, 1993.
Artigo em Italiano | MEDLINE | ID: mdl-7923500

RESUMO

Diagnostic imaging modalities play a key role in the definition of the possible causes of constipation. Barium Enema (BE), Defecography (DG), Intestinal Transit Time (ITT), Computed Axial Tomography (CT) and Magnetic Resonance (MR) are necessary diagnostic tools for the identification either of the possible organic causes of the disease or of the functional disorders. The ITT evaluation is the main investigation to look for functional colic constipation; this method is in fact able to distinguish between the hypertonic type (in which the fecal progression is slowed down to such an extent that radiopaque markers accumulate in the most proximal part of the colon) and the atonic one (characterized by a global slowing down with the markers distributed along the whole colon). DG gives very accurate dynamic documentation of the pathologic alteration of the rectum-anal conduit, as well as of the disease of the supporting and anchoring system and of the levator complex; this type of investigation allows the definition (characterisation) of the different types of the functional rectum-anal constipation. Even in this case TAC and RM can greatly contribute to the definition of the whole picture of the constipation.


Assuntos
Constipação Intestinal/diagnóstico , Constipação Intestinal/diagnóstico por imagem , Constipação Intestinal/etiologia , Defecação , Feminino , Trânsito Gastrointestinal , Humanos , Imageamento por Ressonância Magnética , Masculino , Tomografia Computadorizada por Raios X
20.
Ann Ig ; 1(5): 1197-206, 1989.
Artigo em Italiano | MEDLINE | ID: mdl-2483902

RESUMO

The present report is a research on air samples taken in the operating theatres environment in the hospitals of Umbria to control in order the concentration of anaesthetics in use and to define ambient pollution and to propose changes. The A.A. have divided operating theatres in for groups to analyze the data: 1) operating theatres where there were both systems: air change system and air intake system; 2) operating theatres where there was only the air-change system; 3) operating theatres where there was only the air intake system; 4) operating theatres where there were no systems. These data have been compared with the limit values advised by N.I.O.S.H. The lowest value of pollution have been recorded in those operating theatres with both systems. The A.A. have also compared the ethrane or other alogenated anaesthetics values in the air-change system equipped operating theatres with those (values) found in the intake-air system equipped operating theatres. The lowest values have been recorded in those operating theatres with normal air-change system. Where changes have been made to improve the operating theatres environment, the A.A. have effectuated new controls and found lower values of the anaesthetics levels. The concentration of anaesthetics appeared lower then before.


Assuntos
Poluentes Ocupacionais do Ar/análise , Anestésicos/análise , Salas Cirúrgicas , Gases , Itália , Risco , Ventilação/métodos , Ventilação/normas
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