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1.
Cell ; 179(6): 1409-1423.e17, 2019 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-31778655

RESUMO

The evolution of flight in feathered dinosaurs and early birds over millions of years required flight feathers whose architecture features hierarchical branches. While barb-based feather forms were investigated, feather shafts and vanes are understudied. Here, we take a multi-disciplinary approach to study their molecular control and bio-architectural organizations. In rachidial ridges, epidermal progenitors generate cortex and medullary keratinocytes, guided by Bmp and transforming growth factor ß (TGF-ß) signaling that convert rachides into adaptable bilayer composite beams. In barb ridges, epidermal progenitors generate cylindrical, plate-, or hooklet-shaped barbule cells that form fluffy branches or pennaceous vanes, mediated by asymmetric cell junction and keratin expression. Transcriptome analyses and functional studies show anterior-posterior Wnt2b signaling within the dermal papilla controls barbule cell fates with spatiotemporal collinearity. Quantitative bio-physical analyses of feathers from birds with different flight characteristics and feathers in Burmese amber reveal how multi-dimensional functionality can be achieved and may inspire future composite material designs. VIDEO ABSTRACT.


Assuntos
Adaptação Fisiológica , Plumas/anatomia & histologia , Plumas/fisiologia , Voo Animal/fisiologia , Animais , Evolução Biológica , Aves/anatomia & histologia , Moléculas de Adesão Celular/metabolismo , Citoesqueleto/metabolismo , Derme/anatomia & histologia , Células-Tronco/citologia , Fatores de Tempo , Transcriptoma/genética , Via de Sinalização Wnt/genética
2.
Public Health ; 213: 181-188, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36444823

RESUMO

OBJECTIVES: Housing stability is essential for health and social well-being, and the United States is focused on preventing homelessness among veterans, so this study examined the prevalence of different events related to housing instability among low-income US veterans. STUDY DESIGN: This was a nationally representative survey. METHODS: Using a sample of 1004 low-income veterans in 2021, this study examined the lifetime prevalence and characteristics associated with eviction, home foreclosure, and homelessness among low-income US veterans. RESULTS: In the total sample, 10.9% reported a lifetime history of eviction, 8.0% reported a lifetime history of home foreclosure, and 19.9% reported a lifetime history of homelessness. Among those with a history of homelessness, 39.2% also reported a history of eviction, and 13.9% reported a history of home foreclosure. Hierarchical logistic regression analyses found that for eviction, sociodemographic characteristics (e.g. being Hispanic, having private insurance, and being from the Northeast was associated with lower risk of eviction) together explained 26% of the variance, and clinical characteristics explained an incremental 12% additional variance. For homelessness, sociodemographic characteristics explained 18% of the variance, and clinical characteristics explained an incremental 20% (e.g. diagnosis of schizophrenia or bipolar disorder, any history of suicide attempt, and lower physical health scores were associated with higher risk of homelessness). For home foreclosure, sociodemographic, clinical, and psychosocial variables together only explained 14% of the variance. CONCLUSION: Evictions, home foreclosures, and homelessness are discrete events and occur at relatively high rates among low-income veterans. In addition, homelessness was more associated with biosocial dysfunction, whereas eviction was more closely associated with socio-economic vulnerability, which may inform intervention efforts for both events.


Assuntos
Pobreza , Tentativa de Suicídio , Humanos
3.
Soft Matter ; 16(32): 7535-7543, 2020 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-32700708

RESUMO

We study the responses of fluid-immersed soft hydrogel spheres that are sheared under controlled volume fractions. Slippery, deformable particles along with the density-matched interstitial fluid are sandwiched between two opposing rough cones, allowing studies for a wide range of volume fraction φ both above and below the jamming of granular suspension. We utilize sudden cessations of shearing, accompanied by refraction-matched internal imaging, to supplement the conventional flow-curve measurements. At sufficiently high volume fractions, the settling of particles after the cessations exhibits a continuous yet distinct transition over the change of the shear rate. Such changes back out the qualitative difference in the state of flowing prior to the cessations: the quasi-static yielding of a tightly packed network, as opposed to the rapid sliding of particles mediated by the interstitial fluid whose dynamics depends on the driving rate. In addition, we determine the solid-fluid transition using two independent methods: the extrapolation of stress residues and the estimated yield stress from high values of φ, and the settling of particles upon shear cessations as φ goes across the transition. We also verify the power law on values of characteristic stress with respect to the distance from jamming φ - φc, with an exponent close to 2. These results demonstrate a multitude of relaxation timescales behind the dynamics of soft particles, and raise questions on how we extend the existing paradigms of the flow of a densely packed system when the softness is actively involved.

4.
Public Health ; 168: 107-116, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30739834

RESUMO

OBJECTIVES: This study examines rates of lifetime adult homelessness among foreign-born adults in the United States and how they differ from native-born adults. STUDY DESIGN: Cross-sectional data from a nationally representative US sample were analyzed. METHODS: A sample of 29,896 native-born (weighted 84.1%) and 6404 foreign-born (weighted 16.0%) US adults participating in the National Epidemiologic Survey on Alcohol and Related Conditions-III were compared on rates of homelessness, controlling for sociodemographic characteristics, mental and substance-use disorders, health insurance, and use of welfare. RESULTS: There was no significant difference in rates of lifetime adult homelessness between foreign-born adults and native-born adults (1.0% vs 1.7%). Foreign-born participants were less likely to have various mental and substance-use disorders, less likely to receive welfare, and less likely to have any lifetime incarceration. The number of years foreign-born adults lived in the United States was significantly associated with risk for homelessness. CONCLUSIONS: These findings suggest the 'healthy immigrant effect' applies to the mental health and social functioning of US immigrants but may not necessarily apply to homelessness. Long-standing immigration procedures requiring mental health and psychosocial evaluations may contribute to selection effects.


Assuntos
Emigrantes e Imigrantes/estatística & dados numéricos , Pessoas Mal Alojadas/estatística & dados numéricos , Grupos Populacionais/estatística & dados numéricos , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Estados Unidos
5.
Acta Neurol Scand ; 137(4): 378-391, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29214650

RESUMO

Epileptic seizures are refractory to treatment in approximately one-third of patients despite the recent introduction of many newer antiepileptic drugs (AEDs). Development of novel AEDs therefore remains a high priority. Perampanel is a first-in-class non-competitive selective AMPA receptor antagonist with a unique mechanism of action. Clinical efficacy and safety of perampanel as adjunctive treatment for focal seizures with/without secondary generalization (±SG) and primary generalized tonic-clonic (PGTC) seizures have been established in five phase 3 randomized controlled trials (RCTs), and a long-term extension study, and perampanel is approved as monotherapy for focal seizures ±SG in the USA. In patients with focal seizures ±SG, add-on perampanel resulted in median percent reduction in seizure frequency 23.3%-34.5% and ≥50% responder rate 28.5%-37.6%; in PGTC seizures, these results were 76.5% and 64.2%, respectively. Efficacy among adolescents (reduction in seizure frequency 34.8%-35.6%; ≥50% responder rate 40.9%-45.0%) and elderly people (reduction in seizure frequency 12.5%-16.9%; ≥50% responder rate 22.2%-42.9%) is similar to those in adults, and results remain comparable between Asian (reduction in seizure frequency 17.3%-38.0%) and global populations. Perampanel has been extensively studied in real-world clinical practice, with similar efficacy and safety results to the RCTs (≥50% responder rate 12.8%-75.0%; adverse events of somnolence/sedation, dizziness, ataxia, and behavioral changes). Real-world observational studies suggest that perampanel tolerability can be improved by slow titration (2 mg every 2-4 weeks), and bedtime administration can mitigate somnolence and dizziness. Counseling about the potential for behavioral changes and close monitoring are recommended.


Assuntos
Anticonvulsivantes/uso terapêutico , Piridonas/uso terapêutico , Receptores de AMPA/antagonistas & inibidores , Convulsões/tratamento farmacológico , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Nitrilas , Resultado do Tratamento
6.
Nature ; 484(7394): 355-8, 2012 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-22517162

RESUMO

A hundred years after the discovery of superconductivity, one fundamental prediction of the theory, coherent quantum phase slip (CQPS), has not been observed. CQPS is a phenomenon exactly dual to the Josephson effect; whereas the latter is a coherent transfer of charges between superconducting leads, the former is a coherent transfer of vortices or fluxes across a superconducting wire. In contrast to previously reported observations of incoherent phase slip, CQPS has been only a subject of theoretical study. Its experimental demonstration is made difficult by quasiparticle dissipation due to gapless excitations in nanowires or in vortex cores. This difficulty might be overcome by using certain strongly disordered superconductors near the superconductor-insulator transition. Here we report direct observation of CQPS in a narrow segment of a superconducting loop made of strongly disordered indium oxide; the effect is made manifest through the superposition of quantum states with different numbers of flux quanta. As with the Josephson effect, our observation should lead to new applications in superconducting electronics and quantum metrology.

7.
Bull Math Biol ; 80(9): 2452-2480, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30097919

RESUMO

The Neolithic transition began the spread of early agriculture throughout Europe through interactions between farmers and hunter-gatherers about 10,000 years ago. Archeological evidence produced by radiocarbon dating indicates that the expanding velocity of farming is roughly constant all over Europe. Theoretical understanding of such evidence has been performed from mathematical modeling viewpoint. However, the expanding velocity determined by existing modeling approaches is faster than the observed velocity. For understanding this difference, we propose a three-component reaction-diffusion system which consists of two different types of farmers (sedentary and migratory) and hunter-gatherers from the viewpoint of the influence of farming technology. Our purpose is to study the relation between the expanding velocity of farmers and the farming technology parameter (say, [Formula: see text]). In this paper, we mainly focus on the one-dimensional traveling wave solution with minimal velocity and show that the minimal velocity decreases, as [Formula: see text] increases. This can be compatible with the observed velocity when farming technology is developed. Our results suggest that the reason for the slowdown of the Neolithic transition might be related to the increase in the development of farming technology.


Assuntos
Agricultura/história , Fazendeiros/história , Migração Humana/história , Agricultura/estatística & dados numéricos , Animais , Arqueologia/estatística & dados numéricos , Dieta Paleolítica/história , Domesticação , Europa (Continente) , Fazendeiros/estatística & dados numéricos , História Antiga , Humanos , Conceitos Matemáticos , Modelos Teóricos
8.
Acta Psychiatr Scand ; 136(5): 483-492, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28846800

RESUMO

OBJECTIVE: This study examined the nature and determinants of predominant trajectories of posttraumatic growth (PTG) over time. METHOD: Using data from a prospective, nationally representative survey of 2718 US veterans assessed in 2011, 2013, and 2015, we used latent growth mixture modeling to identify PTG trajectories, and to examine key determinants of PTG trajectories from a comprehensive set of sociodemographic, military, health, and psychosocial variables. RESULTS: Three PTG trajectories were identified, labeled as Low and Decreasing PTG (74.0%), Consistently Moderate PTG (12.0%), and High and Increasing PTG (14.0%). Greater severity of posttraumatic stress disorder symptoms, specifically re-experiencing and avoidance symptoms, at baseline predicted Consistently Moderate and High and Increasing PTG trajectories. Compared to the Low and Decreasing PTG trajectory, the High and Increasing PTG trajectory scored higher on baseline measures of gratitude, purpose in life, Spirituality, and social support. CONCLUSION: Posttraumatic growth is a dynamic process with divergent trajectories. Developing interventions that target certain psychosocial factors may help trauma survivors maintain PTG over time.


Assuntos
Resiliência Psicológica , Apoio Social , Espiritualidade , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Veteranos/estatística & dados numéricos , Adulto , Feminino , Humanos , Masculino , Estudos Prospectivos , Estados Unidos/epidemiologia
10.
Ann Oncol ; 27(4): 660-7, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26782957

RESUMO

BACKGROUND: Neoadjuvant therapy improves long-term survival after oesophagectomy, treating oesophageal cancer, but the evidence to date is insufficient to determine which of the two main neoadjuvant therapy types, chemotherapy (nCT) or chemoradiotherapy (nCRT), is more beneficial. We aimed to compare the effects of nCT with those of nCRT. PATIENTS AND METHODS: This multicentre trial, which was conducted in Sweden and Norway, recruited 181 patients with carcinoma of the oesophagus or the gastro-oesophageal junction who were candidates for curative-intended treatment. The primary end point was histological complete response after neoadjuvant treatment, which has been shown to be correlated with increased long-term survival. Study participants were randomized to nCT or nCRT, followed by surgery with two-field lymphadenectomy. Three cycles of platin/5-fluorouracil were administered in both arms, whereas 40 Gy of concomitant radiotherapy was added in the nCRT arm. RESULTS: The trial met the primary end point, histological complete response being achieved in 28% after nCRT versus 9% after nCT (P = 0.002). Lymph-node metastases were observed in 62% in the nCT group versus 35% in the nCRT group (P = 0.001). The R0 resection rate was 87% after nCRT and 74% after nCT (P = 0.04). There was no difference in overall survival between the treatment arms. CONCLUSION: The addition of radiotherapy to neoadjuvant chemotherapy results in higher histological complete response rate, higher R0 resection rate, and a lower frequency of lymph-node metastases, without significantly affecting survival. CLINICALTRIALSGOV: NCT01362127 (https://clinicaltrials.gov; The full study protocol was registered in the Clinical Trials Database).


Assuntos
Adenocarcinoma/tratamento farmacológico , Neoplasias Esofágicas/tratamento farmacológico , Fluoruracila/administração & dosagem , Terapia Neoadjuvante , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Adulto , Idoso , Intervalo Livre de Doença , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/cirurgia , Junção Esofagogástrica/patologia , Junção Esofagogástrica/cirurgia , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Noruega , Indução de Remissão , Suécia , Resultado do Tratamento
12.
Dis Esophagus ; 29(7): 734-739, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26316181

RESUMO

The therapeutic strategy to be recommended in case of recurrent or persistent squamous cell esophageal cancer after completed definitive chemoradiotherapy (dCRT) has to be documented. Salvage esophagectomy has traditionally been recognized as a viable option, but many clinicians oppose the use of surgery due to the associated excessive morbidity and mortality. 'Second-line' chemoradiotherapy (CRT) without surgery may offer a treatment alternative in these difficult and demanding clinical situations. Until now, no comprehensive attempt has been carried out to compare the respective therapeutic options. A systematic literature search was performed focusing on studies comparing survival and treatment-related mortality in patients submitted to salvage esophagectomy or second-line CRT for recurrent or persistent esophageal squamous cell carcinoma after dCRT. Hazard ratios and risk ratios were calculated to compare the effect of these therapeutic strategies on overall survival and treatment-related mortality, respectively. Four studies containing 219 patients, with persistent or recurrent esophageal squamous cell carcinoma after dCRT, were included in the meta-analysis. The analysis revealed an overall survival benefit following salvage esophagectomy with a pooled hazard ratio for death of 0.42 (95% confidence interval 0.21-0.86, P = 0.017) compared with second-line CRT. A treatment-related mortality of 10.3% was recorded in the 36 patients who were submitted to salvage esophagectomy, while it was impossible to perform a meta-analysis comparing treatment-related mortality between the groups. Salvage esophagectomy offers significant gain in long-term survival compared with second-line CRT, although the surgery is potentially at a price of a high treatment-related mortality.


Assuntos
Adenocarcinoma/terapia , Carcinoma de Células Escamosas/terapia , Neoplasias Esofágicas/terapia , Esofagectomia/mortalidade , Recidiva Local de Neoplasia/terapia , Terapia de Salvação/mortalidade , Adenocarcinoma/patologia , Idoso , Carcinoma de Células Escamosas/patologia , Quimiorradioterapia/mortalidade , Terapia Combinada , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago , Esofagectomia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Modelos de Riscos Proporcionais , Terapia de Salvação/métodos , Resultado do Tratamento
13.
Dis Esophagus ; 29(5): 442-7, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25809837

RESUMO

Dysphagia is the main symptom of cancer of the esophagus and gastroesophageal junction and causing nutritional problems and weight loss, often counteracted by insertion of self-expandable metal stents or nutrition via an enteral route. Clinical observations indicate that neoadjuvant therapy may effectively and promptly alleviate dysphagia, making such nutrition supportive interventions redundant before surgical resection. The objective of the current study was to carefully study the effects of induction neoadjuvant therapy on dysphagia and its subsequent course and thereby investigate the actual need for alimentary gateways for nutritional support. Thirty-five consecutive patients scheduled for neoadjuvant therapy were recruited and assessed regarding dysphagia and appetite at baseline, after the first cycle of preoperative treatment with either chemotherapy alone or with chemoradiotherapy and before surgery. Platinum-based therapy in combination with 5-fluorouracil was administered intravenously days 1-5 every 3 weeks and consisted of three treatments. Patients receiving combined chemoradiotherapy started radiotherapy on day one of second chemotherapy cycle. They received fractions of 2 Gy/day each up to a total dose of 40 Gy. Watson and Ogilvie dysphagia scores were used to assess dysphagia, while appetite was assessed by the Edmonton Assessment System Visual analogue scale-appetite questionnaire. Patients were evaluated at regular outpatient clinic visits or by telephone. The histological tumor response in the surgical specimen was assessed using the Chirieac scale. Ten patients scheduled for neoadjuvant chemotherapy and 25 patients scheduled for chemoradiotherapy were included in the analysis. There was a significant improvement in dysphagia in both treatment groups, according to both scales, already from baseline to the completion of the first chemotherapy cycle which remained to the end of the neoadjuvant treatment (P < 0.001). Appetite also improved after the first chemotherapy cycle (P = 0.03). Body weight did not change during any type of neoadjuvant therapy. We were unable to demonstrate any association between relief of dysphagia and the degree of histological response to neoadjuvant therapy in the surgical specimen. The present study shows that a platin - 5FU-based neoadjuvant chemotherapy, with or without concomitant radiotherapy, effectively and promptly relieves dysphagia in patients presenting with cancers of the esophagus or gastroesophageal junction already after the first cycle.


Assuntos
Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Transtornos de Deglutição/terapia , Neoplasias Esofágicas/terapia , Junção Esofagogástrica , Adulto , Quimiorradioterapia Adjuvante/métodos , Quimioterapia Adjuvante/métodos , Cisplatino/administração & dosagem , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/patologia , Neoplasias Esofágicas/complicações , Neoplasias Esofágicas/patologia , Junção Esofagogástrica/patologia , Feminino , Fluoruracila/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Projetos Piloto , Estudos Prospectivos , Índice de Gravidade de Doença , Resultado do Tratamento
15.
Phys Rev Lett ; 115(22): 223603, 2015 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-26650305

RESUMO

A single superconducting artificial atom can be used for coupling electromagnetic fields up to the single-photon level due to an easily achieved strong coupling regime. Bringing a pair of harmonic oscillators into resonance with the transitions of a three-level atom converts atomic spontaneous processes into correlated emission dynamics. We present the experimental demonstration of two-mode correlated emission lasing in harmonic oscillators coupled via a fully controllable three-level superconducting quantum system (artificial atom). The correlation of emissions with two different colors reveals itself as equally narrowed linewidths and quenching of their mutual phase diffusion. The mutual linewidth is more than 4 orders of magnitude narrower than the Schawlow-Townes limit. The interference between the different color lasing fields demonstrates that the two-mode fields are strongly correlated.

16.
Psychol Med ; 45(1): 165-79, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25065450

RESUMO

BACKGROUND: There is increasing recognition that, in addition to negative psychological consequences of trauma such as post-traumatic stress disorder (PTSD), some individuals may develop post-traumatic growth (PTG) following such experiences. To date, however, data regarding the prevalence, correlates and functional significance of PTG in population-based samples are lacking. METHOD: Data were analysed from the National Health and Resilience in Veterans Study, a contemporary, nationally representative survey of 3157 US veterans. Veterans completed a survey containing measures of sociodemographic, military, health and psychosocial characteristics, and the Posttraumatic Growth Inventory-Short Form. RESULTS: We found that 50.1% of all veterans and 72.0% of veterans who screened positive for PTSD reported at least 'moderate' PTG in relation to their worst traumatic event. An inverted U-shaped relationship was found to best explain the relationship between PTSD symptoms and PTG. Among veterans with PTSD, those with PTSD reported better mental functioning and general health than those without PTG. Experiencing a life-threatening illness or injury and re-experiencing symptoms were most strongly associated with PTG. In multivariable analysis, greater social connectedness, intrinsic religiosity and purpose in life were independently associated with greater PTG. CONCLUSIONS: PTG is prevalent among US veterans, particularly among those who screen positive for PTSD. These results suggest that there may be a 'positive legacy' of trauma that has functional significance for veterans. They further suggest that interventions geared toward helping trauma-exposed US veterans process their re-experiencing symptoms, and to develop greater social connections, sense of purpose and intrinsic religiosity may help promote PTG in this population.


Assuntos
Acontecimentos que Mudam a Vida , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Veteranos/psicologia , Veteranos/estatística & dados numéricos , Adulto , Idoso , Feminino , Indicadores Básicos de Saúde , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Análise de Componente Principal , Escalas de Graduação Psiquiátrica , Religião e Psicologia , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Estados Unidos/epidemiologia
17.
Soft Matter ; 11(20): 4142, 2015 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-25939696

RESUMO

Correction for 'Real-space evidence of the equilibrium ordered bicontinuous double diamond structure of a diblock copolymer' by C. Y. Chu et al., Soft Matter, 2015, 11, 1871-1876.

18.
Soft Matter ; 11(10): 1871-6, 2015 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-25635830

RESUMO

The ordered bicontinuous double diamond (OBDD) structure has long been believed to be an unstable ordered network nanostructure, which is relative to the ordered bicontinuous double gyroid (OBDG) structure for diblock copolymers. Using electron tomography, we present the first real-space observation of the thermodynamically stable OBDD structure in a diblock copolymer composed of a stereoregular block, syndiotactic polypropylene-block-polystyrene (sPP-b-PS), in which the sPP tetrapods are interconnected via a bicontinuous network with Pn3̄m symmetry. The OBDD structure underwent a thermally reversible order-order transition (OOT) to OBDG upon heating, and the transition was accompanied with a slight reduction of domain spacing, as demonstrated both experimentally and theoretically. The thermodynamic stability of the OBDD structure was attributed to the ability of the configurationally regular sPP block to form helical segments, even above its melting point, as the reduction of internal energy associated with the helix formation may effectively compensate the greater packing frustration in OBDD relative to that in the tripods of OBDG.

19.
Br J Surg ; 101(4): 321-38, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24493117

RESUMO

BACKGROUND: The long-term survival benefits of neoadjuvant chemotherapy (NAC) and chemoradiotherapy (NACR) for oesophageal carcinoma are well established. Both are burdened, however, by toxicity that could contribute to perioperative morbidity and mortality. METHODS: MEDLINE, the Cochrane Library and Embase were searched to capture the incidence of any postoperative complications, cardiac complications, respiratory complications, anastomotic leakage, postoperative 30-day mortality, total postoperative mortality and treatment-related mortality in randomized clinical trials comparing NAC or NACR with surgery alone, or NAC versus NACR. Meta-analyses comparing NAC and NACR were conducted by using adjusted indirect comparison. RESULTS: Twenty-three relevant studies were identified. Comparing NAC or NACR with surgery alone, there was no increase in morbidity or mortality attributable to neoadjuvant therapy. Subgroup analysis of NACR for squamous cell carcinoma (SCC) suggested an increased risk of total postoperative mortality and treatment-related mortality compared with surgery alone: risk ratio 1·95 (95 per cent confidence interval 1·06 to 3·60; P = 0·032) and 1·97 (1·07 to 3·64; P = 0·030) respectively. A combination of direct comparison and adjusted indirect comparison showed no difference between NACR and NAC regarding morbidity or mortality. CONCLUSION: Neither NAC nor NACR for oesophageal carcinoma increases the risk of postoperative morbidity or perioperative mortality compared with surgery alone. There was no clear difference between NAC and NACR. Care should be taken with NACR in oesophageal SCC, where an increased risk of postoperative mortality and treatment-related mortality was apparent.


Assuntos
Adenocarcinoma/terapia , Carcinoma de Células Escamosas/terapia , Quimiorradioterapia/efeitos adversos , Neoplasias Esofágicas/terapia , Junção Esofagogástrica/cirurgia , Complicações Pós-Operatórias/etiologia , Adenocarcinoma/mortalidade , Fístula Anastomótica/etiologia , Fístula Anastomótica/mortalidade , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma de Células Escamosas/mortalidade , Quimioterapia Adjuvante/efeitos adversos , Neoplasias Esofágicas/mortalidade , Carcinoma de Células Escamosas do Esôfago , Cardiopatias/etiologia , Cardiopatias/mortalidade , Humanos , Complicações Pós-Operatórias/mortalidade , Ensaios Clínicos Controlados Aleatórios como Assunto , Doenças Respiratórias/etiologia , Doenças Respiratórias/mortalidade , Fatores de Risco , Viés de Seleção
20.
Phys Rev Lett ; 113(6): 063604, 2014 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-25148329

RESUMO

By driving a dispersively coupled qubit-resonator system, we realize an "impedance-matched" Λ system that has two identical radiative decay rates from the top level and interacts with a semi-infinite waveguide. It has been predicted that a photon input from the waveguide deterministically induces a Raman transition in the system and switches its electronic state. We confirm this through microwave response to a continuous probe field, observing near-perfect (99.7%) extinction of the reflection and highly efficient (74%) frequency down-conversion. These proof-of-principle results lead to deterministic quantum gates between material qubits and microwave photons and open the possibility for scalable quantum networks interconnected with waveguide photons.

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