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1.
JAMA Surg ; 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39230915

RESUMEN

Importance: Women on the liver transplant waiting list are less likely to undergo a transplant than men. Recent approaches to resolving this disparity have involved adjustments to Model for End-Stage Liver Disease (MELD) scoring, but this will not affect candidates who rely on exception scores rather than calculated MELD score, the majority of whom have hepatocellular carcinoma (HCC). Objective: To evaluate the association between female sex, candidate size, and access to liver transplant among wait-listed patients with HCC. Design, Setting, and Participants: This retrospective cohort study used US transplant registry data of all adult (aged ≥18 years) wait-listed liver transplant candidates receiving an HCC exception score between January 1, 2010, and March 2, 2023. Exposure: Wait-listed liver transplant candidate sex. Main Outcomes and Measures: The association of female sex with (1) deceased-donor liver transplant (DDLT) and (2) death or waiting list removal for health deterioration were estimated using multivariable competing-risks regression. Results with and without adjustment for candidate height and weight (mediators of the sex disparity) were compared. Results: The cohort included 31 725 candidates with HCC (mean [SD] age at receipt of exception, 61.2 [7.1] years; 76.3% men). Compared with men, women had a lower 1-year cumulative incidence of DDLT (50.8% vs 54.0%; P < .001) and a higher 1-year cumulative incidence of death or delisting for health deterioration (16.2% vs 15.0%; P = .002). After adjustment, without accounting for size, women had a lower incidence of DDLT (subdistribution hazard ratio [SHR], 0.92; 95% CI, 0.89-0.95) and higher incidence of death or delisting (SHR, 1.06; 95% CI, 1.00-1.13) compared with men. When adjusting for candidate height and weight, there was no association of female sex with incidence of DDLT or death or delisting. However, at a height cutoff of 166 cm, short women compared with short men were still less likely to undergo a transplant (SHR, 0.93; 95% CI, 0.88-0.99). Conclusions and Relevance: In this study, women with HCC were less likely to receive a DDLT and more likely to die while wait-listed than men with HCC; these differences were largely (but not entirely) explained by sex-based differences in candidate size. For candidates listed with exception scores, additional changes to allocation policy are needed to resolve the sex disparity, including solutions to improve access to size-matched donor livers for smaller candidates.

2.
Clin Transplant ; 38(6): e15365, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38804605

RESUMEN

BACKGROUND: In May 2019, liver transplant (LT) allocation policy changed to limit MELD exception points for hepatocellular carcinoma (HCC) to median MELD at transplant minus three (MMaT-3). We evaluated this policy's impact on waitlist outcomes for HCC candidates, by race and ethnicity, hypothesizing that the introduction of the MMaT-3 reduced inequities in waitlist outcomes. METHODS: Retrospective cohort study of the Scientific Registry for Transplant Recipients, including all adult LT candidates (N = 10 751) who received HCC exception points from May 17, 2017 to May 18, 2019 (pre-policy; N = 6627) to May 19, 2019 to March 1, 2021 (post-policy; N = 4124). We compared incidence of LT and waitlist removal for death or becoming too sick pre- and post-policy for non-Hispanic White, non-Hispanic Black, Hispanic/Latinx, and Asian patients using competing risk regression adjusted for candidate characteristics. RESULTS: One-year cumulative incidence of LT decreased significantly pre-/post-policy among White (77.4% vs. 64.5%; p < .01) and Black (76.2% vs. 63.1%; p < .01) candidates only, while a 1-year incidence of death/non-LT waitlist removal decreased significantly only among Hispanics (13.4% vs. 7.5%; p < .01). After covariate adjustment, the effect of the policy change was a significantly decreased incidence of LT for White (SHR: .63 compared to pre-policy; p < .001), Black (SHR: .62; p < .001), and Asian (SHR: .68; p = .002), but no change for Hispanic patients. Only Hispanic patients had a significant decrease in death/waitlist removal after the policy change (SHR:  .69; p = .04). Compared to White patients in the pre-policy era, Hispanic (SHR:  .88, p < .007) and Asian candidates (SHR:  .72; p < .001) had lower unadjusted incidence of LT. This disparity was mitigated in the post-policy era where Hispanic patients had higher likelihood of LT than Whites (SHR: 1.22; p = .002). For the outcome of death/non-LT waitlist removal, the only significant difference was a 42% lower incidence of waitlist removal for Asian compared to White patients in the post-policy era (SHR:  .58; p = .03). CONCLUSION: Among LT recipients with HCC, racial/ethnic subpopulations were differentially affected by the MMAT-3 policy, resulting in a post-policy reduction of some of the previous disparities.


Asunto(s)
Carcinoma Hepatocelular , Etnicidad , Neoplasias Hepáticas , Trasplante de Hígado , Obtención de Tejidos y Órganos , Listas de Espera , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Carcinoma Hepatocelular/cirugía , Carcinoma Hepatocelular/mortalidad , Etnicidad/estadística & datos numéricos , Estudios de Seguimiento , Disparidades en Atención de Salud/estadística & datos numéricos , Neoplasias Hepáticas/cirugía , Neoplasias Hepáticas/mortalidad , Pronóstico , Grupos Raciales/estadística & datos numéricos , Sistema de Registros/estadística & datos numéricos , Estudios Retrospectivos , Tasa de Supervivencia , Obtención de Tejidos y Órganos/estadística & datos numéricos , Negro o Afroamericano , Hispánicos o Latinos , Asiático , Blanco
3.
Transplantation ; 108(1): 204-214, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37189232

RESUMEN

BACKGROUND: Patients with hepatocellular carcinoma (HCC) have been overprioritized in the deceased donor liver allocation system. The United Network for Organ Sharing adopted a policy in May 2019 that limited HCC exception points to the median Model for End-Stage Liver Disease at transplant in the listing region minus 3. We hypothesized this policy change would increase the likelihood to transplant marginal quality livers into HCC patients. METHODS: This was a retrospective cohort study of a national transplant registry, including adult deceased donor liver transplant recipients with and without HCC from May 18, 2017, to May 18, 2019 (prepolicy) to May 19, 2019, to March 1, 2021 (postpolicy). Transplanted livers were considered of marginal quality if they met ≥1 of the following: (1) donation after circulatory death, (2) donor age ≥70, (3) macrosteatosis ≥30% and (4) donor risk index ≥95th percentile. We compared characteristics across policy periods and by HCC status. RESULTS: A total of 23 164 patients were included (11 339 prepolicy and 11 825 postpolicy), 22.7% of whom received HCC exception points (prepolicy versus postpolicy: 26.1% versus 19.4%; P = 0.03). The percentage of transplanted donor livers meeting marginal quality criteria decreased for non-HCC (17.3% versus 16.0%; P < 0.001) but increased for HCC (17.7% versus 19.4%; P < 0.001) prepolicy versus postpolicy. After adjusting for recipient characteristics, HCC recipients had 28% higher odds of being transplanted with marginal quality liver independent of policy period (odds ratio: 1.28; confidence interval, 1.09-1.50; P < 0.01). CONCLUSIONS: The median Model for End-Stage Liver Disease at transplant in the listing region minus 3 policy limited exception points and decreased the quality of livers received by HCC patients.


Asunto(s)
Carcinoma Hepatocelular , Enfermedad Hepática en Estado Terminal , Neoplasias Hepáticas , Trasplante de Hígado , Obtención de Tejidos y Órganos , Adulto , Humanos , Carcinoma Hepatocelular/cirugía , Carcinoma Hepatocelular/patología , Trasplante de Hígado/efectos adversos , Neoplasias Hepáticas/cirugía , Neoplasias Hepáticas/patología , Enfermedad Hepática en Estado Terminal/diagnóstico , Enfermedad Hepática en Estado Terminal/cirugía , Estudios Retrospectivos , Donadores Vivos , Selección de Paciente , Índice de Severidad de la Enfermedad , Políticas , Listas de Espera
4.
PLoS One ; 18(5): e0285611, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37172020

RESUMEN

The splash phenomenon and the scale of the surface deformation of post-fire soils in the variants of various hydrophobicity and moisture content were studied. Splash erosion is the result of the impact of a single water drop and was analysed using high-speed cameras, while the surface deformation was parameterized using a structured light scanner. The extremely water-repellent variant (dry_V) showed distinct differences, expressed primarily in the number of ejected particles, which was 2.5 times higher than in the four soils with lower levels of hydrophobicity. It was also observed that as a result of the drop impact onto an extremely hydrophobic soil surface, a form known as liquid marble was created inside the crater. Soil moisture content determined the manner, scale and dynamics of the splash erosion. In the case of wet soils, the phenomenon proceeded up to five times faster, and as a result of the drop impact, a large number of fine particles were ejected, which reached nearly twice the velocities and three times the displacement distances compared to the dry soil group. However, the particles and/or aggregate splashed on the dry samples were larger, which also translated into the formation of craters up to twice as extensive as those in the wet soils.


Asunto(s)
Suelo , Agua , Suelo/química , Interacciones Hidrofóbicas e Hidrofílicas , Agua/química
5.
J Exp Bot ; 74(17): 5255-5272, 2023 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-37249250

RESUMEN

Pistia stratiotes is an aquatic plant with a complex structure that allows it to stay afloat. It grows quickly, and in large numbers becomes an undesirable plant as an invasive species. Describing the dynamics of a water drop splash on P. stratiotes leaves can contribute to increasing knowledge of its behavior and finding alternative methods for eradicating it or using it for the benefit of the environment. The non-wettable surface of P. stratiotes presents a complex structure-simple uniseriate trichomes and also ridges and veins. We analyzed the drop impact on a leaf placed on the water surface and recorded it by high-speed cameras. Based on the recordings, quantitative and qualitative analyses were performed. After impacting the leaf, the water drop spread until it reached its maximum surface area accompanied by the ejection of early droplets in the initial stage. Thereafter, three scenarios of water behavior were observed: (i) drop receding and stabilization; (ii) drop receding and ejection of late droplets formed in the later stage as an effect of elastic deformation of the leaf; and (iii) drop breaking apart and ejection of late droplets. The results indicated that the increasing kinetic energy of the impacting drops expressed by the Weber number and the complex leaf surface have an effect on the course of the splash. The simple uniseriate trichomes of the P. stratiotes leaf and the high energy of the falling drops were responsible for the formation and characteristics of the early droplets. The presence of ridges and veins and the leaf's mechanical response had an impact on the occurrence of late droplets.


Asunto(s)
Araceae , Interacciones Hidrofóbicas e Hidrofílicas , Plantas , Hojas de la Planta/fisiología , Agua/análisis
6.
Sci Adv ; 8(40): eabq7533, 2022 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-36197989

RESUMEN

The field of spinoptronics is underpinned by good control over photonic spin-orbit coupling in devices that have strong optical nonlinearities. Such devices might hold the key to a new era of optoelectronics where momentum and polarization degrees of freedom of light are interwoven and interfaced with electronics. However, manipulating photons through electrical means is a daunting task given their charge neutrality. In this work, we present electrically tunable microcavity exciton-polariton resonances in a Rashba-Dresselhaus spin-orbit coupling field. We show that different spin-orbit coupling fields and the reduced cavity symmetry lead to tunable formation of the Berry curvature, the hallmark of quantum geometrical effects. For this, we have implemented an architecture of a photonic structure with a two-dimensional perovskite layer incorporated into a microcavity filled with nematic liquid crystal. Our work interfaces spinoptronic devices with electronics by combining electrical control over both the strong light-matter coupling conditions and artificial gauge fields.

7.
ACS Omega ; 7(11): 9785-9795, 2022 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-35350322

RESUMEN

Flexoelectricity may have an important impact on the switching properties of nematic and cholesteric liquid crystals due to the linear coupling between the flexoelectric polarization of the liquid crystal and the applied electric field. This coupling is the origin of the extraordinary electro-optic effect in cholesterics aligned in the uniform lying helix texture, resulting in fast switching and field control of both rise and fall times. Therefore, the flexoelectric properties of the liquid crystals have become an important issue when designing and synthesizing liquid crystal materials and/or preparing their mixtures with appropriate flexoelectric compounds (dopants). Here, we report on the flexoelectric polarization of a highly polar nematic liquid crystal host enhanced by doping it with two newly synthesized dopants SK 1-6 and SK 1-8, possessing a hockey stick molecular shape, and comparing their doping effect with the one of the dimeric dopants CB7CB possessing a symmetric bend molecular shape. All dopants were dissolved in small concentration (5 wt %) in the nematic host so that the linear approximation of the dependence of the difference between splay e s and bend e b flexoelectric constants, that is, (e s - e b), on the concentration of the dopant in the host material can be applied. In this way, (e s - e b) was estimated for the hockey stick dopants SK 1-6 and SK 1-8 to be 0.182 and 0.204 nC/m, respectively. The obtained flexoelectric polarization of these dopants is among the highest reported in the literature so far.

8.
PLoS One ; 17(3): e0265546, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35333882

RESUMEN

The formation of craters is an important issue in the investigations of the surface of the earth and other planets. The aim of the study was to check whether the different textures of sand beds affect the size and dynamics of the formation of craters and ejection curtain after high-velocity impacts. The experiments were conducted using an aluminium impactor at two impact speeds (~700 and ~1300 m∙s-1) and a sand bed composed of either a broad range of sizes (<2.0 mm) or any of the three fractions obtained from it (<0.5, 0.5-1, 1-2 mm). The diameters, depths, wall slope, and rim heights of the resulting craters were measured. The ejecta curtain was characterized by the inclination angle of walls, base diameter, and expansion velocity. The mass of the transferred material and the depth of the impactor penetration were also determined. Additionally, the results were used to calculate dimensionless parameters commonly considered in crater studies (πV, π2 and α). The texture of the sand most clearly influenced the diameters of the craters, its effect could also be seen in the case of the distance covered by the ejected material. This information appears to be relevant for future research, providing some rationale to help assess in which aspects of the phenomenon the texture may be important.


Asunto(s)
Planetas , Arena , Planeta Tierra
9.
PLoS One ; 17(1): e0262203, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34995324

RESUMEN

Soil splash is the first step in the process of water erosion, where impacting raindrops cause the detachment and transport of soil material. One of the factors that strongly influences the magnitude of soil splash is the incline of the surface (slope). The aim of this study was to investigate the effect of the slope on the course of the splash phenomenon caused by single-drop impact (one drop impact per soil sample), with respect to the mass and proportions of the ejected material, taking into account its division into solid and liquid phases i.e. soil and water. The investigation was carried out using three types of soil with different textures, in moistened (pressure head corresponding to -1.0 kPa) and air-dry (-1500 kPa) conditions. The soil samples were on three angles of slope, being 5°, 15°, and 30°, respectively. After a single-drop impact with a diameter of 4.2 mm, the ejected material was collected using a splash cup. The following quantities of splashed material were measured: the total mass, the mass of the solid phase, and the mass of the liquid phase. Additionally, the distribution and proportions (soil/water) of the splashed material were analysed in both the upslope and downslope directions. It was found that: (i) the change of slope had a variable influence on the measured quantities for different soils; (ii) in the case of moistened samples, the measured values were mainly influenced by the texture, while in the dry samples, by the angle of the slope; (iii) with the increase of slope, the splashed material was mostly ejected in the downslope direction (irrespective of moisture conditions); (iv) in the moistened samples, the ejected material consisted mostly of water, while in the dry samples it was soil-this occurred for material ejected both upslope and downslope. The obtained results are important for improving the physical description of the process of splash erosion. A more thorough understanding and better recognition of the mechanisms governing this phenomenon at all stages could contribute to the development of more effective methods for protecting soil against erosion.


Asunto(s)
Transición de Fase , Lluvia , Suelo/química , Agua/análisis , Agua/química , Fenómenos Mecánicos , Propiedades de Superficie
10.
Sensors (Basel) ; 23(1)2022 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-36616719

RESUMEN

Water erosion is an unfavorable phenomenon causing soil degradation. One of the factors causing water erosion is heavy or prolonged rainfall, the first effect of which is the deformation of the soil surface and the formation of microcraters. This paper presents an overview of research methods allowing the study of microcraters as well as the process of their formation. A tabular summary of work on the measurements of various quantities describing the craters is presented. The said quantities are divided into three groups: (i) static quantities, (ii) dynamic quantities, and (iii) dimensionless parameters. The most important measurement methods used to study crater properties, such as (i) basic manual measurement methods, (ii) photography, (iii) high-speed imaging, (iv) profilometers, (v) 3D surface modelling, and (vi) computed tomography (CT) and its possibilities and limitations are discussed. The main challenges and prospects of research on soil surface deformation are also presented.

11.
J Am Acad Dermatol ; 86(1): 122-130, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34555481

RESUMEN

BACKGROUND: Psoriasis affects 0.13%-2.1% of children and adolescents. Despite a high unmet need, the current treatment options approved for pediatric psoriasis are limited. OBJECTIVE: To evaluate the efficacy and safety of 2 secukinumab dosage regimens (low dose: 75/75/150 mg; high dose: 75/150/300 mg) stratified and randomized by weight (<25 kg, 25 to <50 kg, ≥50 kg) and disease severity (moderate, severe) in pediatric patients aged 6-<18 years with moderate to severe plaque psoriasis. METHODS: This is a phase 3, open-label, randomized, multicenter study (NCT03668613). RESULTS: Both secukinumab doses were superior to historical placebo with respect to psoriasis area and severity index (PASI)-75/90 and investigator global assessment 0/1 responses at week 12. The estimated probability of a positive treatment effect (ie, log odds ratio > 0) for low- or high-dose secukinumab compared to historical placebo is 1 (ie, 100%). For the low and high doses at week 12, the investigator global assessment 0/1 response rates were 78.6% and 83.3%, respectively, and the PASI-90 response rates were 69% and 76.2%, respectively. The PASI-75 response rate was 92.9% for both the doses. LIMITATIONS: This is an open-label study design without a control arm. CONCLUSION: Secukinumab dosing regimens were efficacious and well tolerated in pediatric patients with moderate to severe plaque psoriasis.


Asunto(s)
Anticuerpos Monoclonales , Psoriasis , Adolescente , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales Humanizados , Niño , Método Doble Ciego , Humanos , Psoriasis/inducido químicamente , Psoriasis/diagnóstico , Psoriasis/tratamiento farmacológico , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
12.
Phys Rev Lett ; 127(19): 190401, 2021 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-34797125

RESUMEN

Spin-orbit interactions which couple the spin of a particle with its momentum degrees of freedom lie at the center of spintronic applications. Of special interest in semiconductor physics are Rashba and Dresselhaus spin-orbit coupling. When equal in strength, the Rashba and Dresselhaus fields result in SU(2) spin rotation symmetry and emergence of the persistent spin helix only investigated for charge carriers in semiconductor quantum wells. Recently, a synthetic Rashba-Dresselhaus Hamiltonian was shown to describe cavity photons confined in a microcavity filled with optically anisotropic liquid crystal. In this Letter, we present a purely optical realization of two types of spin patterns corresponding to the persistent spin helix and the Stern-Gerlach experiment in such a cavity. We show how the symmetry of the Hamiltonian results in spatial oscillations of the spin orientation of photons traveling in the plane of the cavity.

13.
Chin Med J (Engl) ; 133(22): 2665-2673, 2020 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-33060370

RESUMEN

BACKGROUND: Psoriasis is a chronic inflammatory skin disease, affecting about 0.6% of the Chinese population. Many patients are not well controlled by conventional treatments, thus there is need for new treatment regimens. In this study, we assessed the efficacy and safety of secukinumab in Chinese patients with moderate to severe plaque psoriasis. METHODS: This study was a 52-week, multicentre, randomized, double-blind, placebo-controlled, parallel-group, Phase 3 trial. A sub-population of study participants (≥18 years) of Chinese ethnicity were randomized to receive subcutaneous injections of 300 or 150 mg secukinumab, or placebo. The co-primary endpoints were psoriasis area severity index (PASI) 75 and Investigator's Global Assessment (IGA) 0/1 at Week 12. RESULTS: A total of 441 Chinese patients were enrolled in this study. Co-primary outcomes were achieved; 300 and 150 mg secukinumab were superior to placebo as shown in the proportion of patients that achieved PASI 75 (97.7% and 87.2% vs. 3.7%, respectively; P < 0.001), and IGA 0/1 (82.3% and 69.7% vs. 2.7%; P < 0.001) at Week 12. Treatment efficacy was maintained until Week 52. There was no increase in overall adverse events with secukinumab relative to placebo throughout the 52-week period. CONCLUSION: Secukinumab is highly effective and well tolerated in Chinese patients with moderate to severe plaque psoriasis. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03066609; https://clinicaltrials.gov/ct2/show/record/NCT03066609.


Asunto(s)
Anticuerpos Monoclonales , Psoriasis , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales Humanizados , China , Método Doble Ciego , Humanos , Psoriasis/tratamiento farmacológico , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
14.
Am J Case Rep ; 21: e924280, 2020 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-32883944

RESUMEN

BACKGROUND Carcinoid tumor is the most frequent neuroendocrine tumor (NET) that causes liver metastases. One of the best methods to assess this type of pathology is magnetic resonance imaging with hepatocyte-specific contrast media with low molecular weight gadolinium chelate Gd-BOPTA. As these lesions do not contain hepatocytes, they present as hypointense on MRI in comparison with liver tissue which enhances this type of contrast. CASE REPORT In this article, we present a case of a 65-year-old female patient who was admitted to the Emergency Department with abdominal pain. Computed tomography revealed a single focal lesion in her liver. The patient underwent further evaluation using magnetic resonance imaging (MRI). The hepatobiliary phase MRI showed an unspecific homogenous enhancement of the hepatobiliary agent Gd-BOPTA. Since the lesion was interpreted as a non-characteristic lesion, the patient was discharged from the hospital with a recommendation for early follow-up. The follow-up MRI 6 months after discharge disclosed multiple liver metastases. CONCLUSIONS Liver metastases generally demonstrate enhancement of hepatobiliary contrast agents in the T1-weighted hepatocellular phase. Metastasis from a carcinoid tumor may also demonstrate this enhancement.


Asunto(s)
Tumor Carcinoide , Neoplasias Hepáticas , Compuestos Organometálicos , Anciano , Tumor Carcinoide/diagnóstico por imagen , Medios de Contraste , Femenino , Humanos , Hígado , Neoplasias Hepáticas/diagnóstico por imagen , Imagen por Resonancia Magnética , Meglumina/análogos & derivados
15.
Radiol Case Rep ; 15(6): 775-779, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32322330

RESUMEN

Trifurcation is rare anatomical variant of the common carotid artery (CCA) termination. Knowledge of such alteration may prevent from the unintentional complications and influence on the course of various invasive medical procedures carried in the neck region. The best way to assess anatomy of neck arteries is computed tomography angiography (CTA). In this article we present a case of 64-year old male patient, who was admitted to the department with a chronic headaches and dizziness. CTA revealed a trifurcation of the right common carotid artery into: internal carotid artery and two branches of external carotid artery. The aneurysm of the proximal part of Vertebral Artery was also observed and it was considered as a cause of the symptoms which should not be related to the anatomical variety of the CCA.

16.
Science ; 366(6466): 727-730, 2019 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-31699934

RESUMEN

Spin-orbit interactions lead to distinctive functionalities in photonic systems. They exploit the analogy between the quantum mechanical description of a complex electronic spin-orbit system and synthetic Hamiltonians derived for the propagation of electromagnetic waves in dedicated spatial structures. We realize an artificial Rashba-Dresselhaus spin-orbit interaction in a liquid crystal-filled optical cavity. Three-dimensional tomography in energy-momentum space enabled us to directly evidence the spin-split photon mode in the presence of an artificial spin-orbit coupling. The effect is observed when two orthogonal linear polarized modes of opposite parity are brought near resonance. Engineering of spin-orbit synthetic Hamiltonians in optical cavities opens the door to photonic emulators of quantum Hamiltonians with internal degrees of freedom.

17.
Liver Transpl ; 25(12): 1800-1810, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31539195

RESUMEN

The high efficacy of current hepatitis C virus (HCV) therapy and increased numbers of HCV-infected deceased donors have changed the paradigm of HCV in liver transplantation (LT). Modeling studies have been performed to evaluate the optimal timing of HCV treatment (before versus after LT) in HCV-infected patients and to assess the cost-effectiveness of transplanting HCV-infected livers into HCV- patients. However, these models rely on historical data and have not quantified the temporal changes in the median Model for End-Stage Liver Disease (MELD) score at transplant of recipients of an HCV-infected liver across geographic areas. We performed a retrospective cohort study of Organ Procurement and Transplantation Network/United Network for Organ Sharing (UNOS) data of nonstatus 1 deceased donor LT recipients from January 1, 2016, to December 31, 2018, and we calculated the difference in allocation MELD score in recipients of HCV nucleic acid test (NAT)- versus NAT+ livers by year and UNOS region. We used Pearson correlation coefficients to assess the relationship between MELD score difference in recipients of HCV NAT+ versus HCV NAT- livers and the proportion of non-HCV recipients of HCV NAT+ livers. Nationally, the allocation MELD score difference at LT in recipients of HCV NAT+ versus NAT- livers did not change (4-point difference). This stability was seen in regions 3, 5, and 10. In regions 1, 7, 8, 9, and 11, the MELD score difference decreased, which is a diminishing advantage. However, in regions 2 and 4, it increased, which is a rising advantage. In 2018, recipients of HCV NAT+ livers had a lower MELD score in 9/11 regions, and the MELD score advantage of accepting HCV NAT+ livers had a moderate inverse correlation with the regional use in non-HCV patients (r = -0.53). These data should be used to inform clinicians of the pre- and post-LT trade-offs of HCV treatment.


Asunto(s)
Selección de Donante/tendencias , Enfermedad Hepática en Estado Terminal/cirugía , Hepatitis C/diagnóstico , Trasplante de Hígado/tendencias , Asignación de Recursos/tendencias , Viremia/diagnóstico , Adulto , Aloinjertos/provisión & distribución , Aloinjertos/virología , Antivirales/uso terapéutico , Selección de Donante/estadística & datos numéricos , Enfermedad Hepática en Estado Terminal/diagnóstico , Geografía , Hepacivirus/genética , Hepacivirus/aislamiento & purificación , Hepatitis C/sangre , Hepatitis C/tratamiento farmacológico , Hepatitis C/transmisión , Humanos , Hígado/virología , Trasplante de Hígado/estadística & datos numéricos , ARN Viral/aislamiento & purificación , Asignación de Recursos/estadística & datos numéricos , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Receptores de Trasplantes/estadística & datos numéricos , Estados Unidos , Viremia/tratamiento farmacológico , Viremia/transmisión , Viremia/virología
18.
J Child Neurol ; 34(10): 593-597, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31113283

RESUMEN

The main objective of this study was to assess the efficacy, safety, and retention rates of levetiracetam monotherapy in children with epilepsy. A retrospective review of pediatric patients receiving levetiracetam monotherapy at 2 large tertiary epilepsy centers over an 11-year period was conducted. One hundred two patients using levetiracetam monotherapy with a mean age of 13.1 years were identified. For the entire cohort, a 6-month retention rate was 61.1% and a 12-month retention rate 53.1%. With regard to seizure freedom, 46.8% of those patients that remained on monotherapy for at least 6 months became seizure free. Twelve-month seizure freedom was reached by 41.2%. About one-third (32.4%) of patients reported adverse effects, with irritability, moodiness, and depression being the most common. Despite a number of patients that reported adverse events, levetiracetam monotherapy was found to be potentially effective in this cohort of children with epilepsy and warrants further, prospective studies.


Asunto(s)
Anticonvulsivantes/uso terapéutico , Epilepsia/tratamiento farmacológico , Levetiracetam/uso terapéutico , Adolescente , Anticonvulsivantes/efectos adversos , Niño , Preescolar , Femenino , Humanos , Lactante , Levetiracetam/efectos adversos , Masculino , Cooperación del Paciente , Estudios Retrospectivos , Resultado del Tratamiento
20.
Beilstein J Nanotechnol ; 10: 71-78, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30680280

RESUMEN

We report a threshold voltage decrease in a nematic liquid crystal compound, 4-cyano-4'-pentylbiphenyl (5CB), doped with graphene oxide (GO) flakes at a concentration of 0.05-0.3 wt %. The threshold voltage decrease was observed at the same concentration in electro-optic and dielectric spectroscopy measurements. The effect is related to the disrupted planar alignment due to the strong π-π stacking between the 5CB's benzene rings and the graphene oxide's structure. Additionally, we present the GO concentration dependence on the isotropic-nematic phase transition temperature, electric anisotropy, splay elastic constant, switch-on time, and switch-off time. The shape and dimensions of the GO flakes were studied using atomic force microscopy (AFM) and scanning electron microscopy (SEM). The influence of the GO concentration on the physical properties and switching process in the presence of the electric field was discussed.

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