RESUMO
Globally, there has been a recent surge in 'citizens' assemblies'1, which are a form of civic participation in which a panel of randomly selected constituents contributes to questions of policy. The random process for selecting this panel should satisfy two properties. First, it must produce a panel that is representative of the population. Second, in the spirit of democratic equality, individuals would ideally be selected to serve on this panel with equal probability2,3. However, in practice these desiderata are in tension owing to differential participation rates across subpopulations4,5. Here we apply ideas from fair division to develop selection algorithms that satisfy the two desiderata simultaneously to the greatest possible extent: our selection algorithms choose representative panels while selecting individuals with probabilities as close to equal as mathematically possible, for many metrics of 'closeness to equality'. Our implementation of one such algorithm has already been used to select more than 40 citizens' assemblies around the world. As we demonstrate using data from ten citizens' assemblies, adopting our algorithm over a benchmark representing the previous state of the art leads to substantially fairer selection probabilities. By contributing a fairer, more principled and deployable algorithm, our work puts the practice of sortition on firmer foundations. Moreover, our work establishes citizens' assemblies as a domain in which insights from the field of fair division can lead to high-impact applications.
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Pessoal Administrativo/organização & administração , Algoritmos , Democracia , Formulação de Políticas , Probabilidade , Conjuntos de Dados como Assunto , Feminino , Humanos , Masculino , Distribuição AleatóriaRESUMO
The body of vertebrate embryos forms by posterior elongation from a terminal growth zone called the tail bud. The tail bud is a source of highly motile cells that eventually constitute the presomitic mesoderm (PSM), a tissue that plays an important role in elongation movements. PSM cells establish an anterior-posterior cell motility gradient that parallels a gradient associated with the degradation of a specific cellular signal (FGF) known to be implicated in cell motility. Here, we combine the electroporation of fluorescent reporters in the PSM with time-lapse imaging in the chicken embryo to quantify cell diffusive movements along the motility gradient. We show that a simple microscopic model for random cell motility induced by FGF activity along with geometric confinement leads to rectified tissue elongation consistent with our observations. A continuum analog of the microscopic model leads to a macroscopic mechano-chemical model for tissue extension that couples FGF activity-induced cell motility and tissue rheology, and is consistent with the experimentally observed speed and extent of elongation. Together, our experimental observations and theoretical models explain how the continuous addition of cells at the tail bud combined with lateral confinement can be converted into oriented movement and drive body elongation.
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Embrião de Mamíferos , Mesoderma , Animais , Movimento Celular , Embrião de Galinha , Mesoderma/metabolismo , Transdução de Sinais , VertebradosRESUMO
Biomolecular and physical cues of the extracellular matrix environment regulate collective cell dynamics and tissue patterning. Nonetheless, how the viscoelastic properties of the matrix regulate collective cell spatial and temporal organization is not fully understood. Here we show that the passive viscoelastic properties of the matrix encapsulating a spheroidal tissue of breast epithelial cells guide tissue proliferation in space and in time. Matrix viscoelasticity prompts symmetry breaking of the spheroid, leading to the formation of invading finger-like protrusions, YAP nuclear translocation and epithelial-to-mesenchymal transition both in vitro and in vivo in a Arp2/3-complex-dependent manner. Computational modelling of these observations allows us to establish a phase diagram relating morphological stability with matrix viscoelasticity, tissue viscosity, cell motility and cell division rate, which is experimentally validated by biochemical assays and in vitro experiments with an intestinal organoid. Altogether, this work highlights the role of stress relaxation mechanisms in tissue growth dynamics, a fundamental process in morphogenesis and oncogenesis.
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Células Epiteliais , Matriz Extracelular , Viscosidade , ElasticidadeRESUMO
India is home to one-fifth of the world's population and is currently the fastest-growing economy. As the health industry is growing, India needs to develop robust implementation of evidence-based health care addressing the major public health issues. Two of such issues India is grappling with are the establishment of stroke care and the reduction of road accidents. Australia has achieved notable success in implementing stroke care and reducing road accidents. In stroke, Australian initiatives include dedicated stroke units, the development of clinical guidelines, the implementation of acute interventions, the establishment of a national stroke foundation, and the stroke registry. As a result, the combined, primary, and secondary prevention measures, acute treatment, and rehabilitation have reduced the total disease burden of stroke from 2003 to 2023 by 53 per cent, from 7.4 to 3.5 Disability Adjusted Life Years (DALYS) per 1,000 population, which is a 56 per cent decline in fatal burden and 23 per cent decline in non-fatal burden. For road safety, Australia implemented evidence-based practices such as education, legislation including mandatory use of seat belts, and other road safety initiatives. Data show that seat belt use reached 98 per cent in Australia in 2023. Furthermore, about 20 per cent of drivers as well as passengers who were killed in crashes in 2024 did not wear seat belts. The reduction of speed limits in built-up areas, the adoption of monitoring technology, and the clever use of infrastructure are proving to be effective in reducing fatalities and serious injuries. Australia's implementation research can provide valuable insights into the efforts of mitigating the impact of stroke and enhancing road safety in India.
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Acidentes de Trânsito , Acidente Vascular Cerebral , Humanos , Índia/epidemiologia , Austrália/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/prevenção & controle , Acidente Vascular Cerebral/terapia , Acidentes de Trânsito/prevenção & controle , Cintos de Segurança/estatística & dados numéricosRESUMO
The Rehabilitation Medicine Society of Australia and New Zealand advocates the safe, effective and evidence-based use of botulinum toxin type A for spasticity management. The process requires appropriate training, alongside considerable knowledge and skills, to maximise efficacy. The processes before and after injection contribute to effectiveness. The gold standard of managing spasticity is for assessment by a multidisciplinary specialist team, deriving patient-centric goals, and designing an injection protocol to match these goals. The patient and/or carers are considered part of the decision-making team. Postinjection therapy and measurement of goal achievement are highly recommended as part of the wider holistic approach to management. The Society believes treatment failures can be minimised by following clear clinical guidelines.
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Toxinas Botulínicas Tipo A , Humanos , Toxinas Botulínicas Tipo A/uso terapêutico , Nova Zelândia , Austrália , Falha de TratamentoRESUMO
OBJECTIVE: To observe the effect of overground gait training with 'Mobility Assisted Robotic System-MARS' on gait parameters in patients with stroke. PATIENTS & METHODS: This prospective pre-post study was conducted in a tertiary teaching research hospital with 29 adult stroke patients, with age up to 65 years. Patients fulfilling the inclusion criteria were divided in 2 groups based on the duration of stroke (≤ 6 months-sub-acute & > 6 months-chronic stroke) and provided overground gait training with MARS robot for 12 sessions (1 h/session) over a period of 2-3 weeks. Primary outcome measures were; 10-Meter walk test-10MWT, 6-min' walk test-6MWT and Timed up & Go-TUG tests. Secondary outcome measures were Functional Ambulation Category-FAC, Modified Rankin Scale-MRS and Scandinavian Stroke Scale-SSS. RESULTS: No adverse events were reported. Twenty-five patients who were able to perform 10-MWT at the beginning of study were included in the final analysis with 12 in sub-acute and 13 in chronic stroke group. All primary and secondary outcome measures showed significant improvement in gait parameters at the end of the training (p < 0.05) barring 10-Meter walk test in sub-acute stroke group (p = 0.255). Chronic stroke group showed significant minimum clinically important difference-MCID difference in endurance (6MWT) at the end of the training and both groups showed better 'minimal detectable change-MDC' in balance (TUG) at the end of the training. CONCLUSIONS: Patients in both the groups showed significant improvement in walking speed, endurance, balance and independence at the end of the training with overground gait training with MARS Robot. CLINICAL TRIAL REGISTRY: National Clinical Trial Registry of India (CTRI/2021/08/035695,16/08/2021).
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Transtornos Neurológicos da Marcha , Procedimentos Cirúrgicos Robóticos , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Adulto , Humanos , Terapia por Exercício , Marcha , Estudos Prospectivos , Acidente Vascular Cerebral/complicações , Resultado do Tratamento , CaminhadaRESUMO
BACKGROUND: Cancer-related fatigue (CRF) is a common debilitating condition. International evidence supports an exercise prescription for CRF. The majority of Australians with cancer do not meet recommended exercise targets. AIMS: To analyse the effects of a guideline-based supervised exercise programme on CRF among a representative private hospital cancer patient sample (n = 268). METHODS: We collected data from 268 patients recruited from haematology and oncology over a 5-year period. Participants underwent a 3-month CRF exercise programme based on internationally recognised exercise guidelines. The programme, conducted by a multidisciplinary team, operated twice weekly sessions of 2 h duration comprising aerobic, resistance and balance exercises; hydrotherapy and condition counselling; fatigue management; and dietetic, speech pathology and swallowing education (head and neck cancers). The effect of the programme was measured in relation to the following outcomes: Functional Assessment of Chronic Illness Therapy, Fatigue (self-reported fatigue); Functional Assessment of Cancer Therapy, general quality of life (health-related quality of life in cancer); six-minute walk test; and Lawton's Instrumental Activities of Daily Living Scale. RESULTS: Multivariate outcomes showed statistically significant improvements in all four major outcome measures, plus a programme effect of greater than 0.7 for each outcome variable. The programme treatment outcomes were consistent over the 5 years of the programme. CONCLUSIONS: The outcomes of this programme contribute to exercise guidelines in Australia. Currently only position statements exist on the subject, but there are no programme guidelines. An exercise prescription is critical to cancer outcomes. This programme is likely to benefit cancer survivors experiencing CRF across private and public hospitals in Australia.
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Neoplasias , Qualidade de Vida , Humanos , Atividades Cotidianas , Pacientes Ambulatoriais , Austrália/epidemiologia , Terapia por Exercício , Neoplasias/complicações , Neoplasias/terapia , Fadiga/etiologia , Fadiga/terapiaRESUMO
INTRODUCTION: Uncommon but increasingly diagnosed, ipsilateral femoral neck and shaft fracture represents a complex injury pattern with challenging management. The conundrum involves optimal diagnostic modality, timing of surgery, sequence of fixation, and the choice of implant. METHODOLOGY: A retrospective review was conducted at a Level-I trauma centre to assess the outcome of concomitant femoral neck and shaft fractures managed with various implants and attempt to provide solutions to the aforementioned queries. The time between injury and definitive surgery, choice of implant, sequence of fixation, time to fracture union, and complications were documented and analyzed. RESULTS: A total of 46 patients were included in the study wherein associated neck fracture was identified preoperatively in 93.5% of patients. In patients with isolated limb fractures, the mean time to surgery was 16.7 ± 5 h whereas patients with polytrauma witnessed an average delay of 4.6 days before fracture fixation. 72% of patients were managed by dual implants and in the remaining both the fractures were addressed using a single implant with no union time difference amongst implants. The mean time to the union for neck fracture was 21.7 weeks and 24.2 weeks for shaft femur fracture. 21.7% patients developed delayed union of fracture shaft femur and infection complicated 11% shaft fractures. CONCLUSION: Although, 6% neck fractures were missed in the series, we advocate that careful pre/intra/post-operative fluoroscopic evaluation of the femoral neck along with a low threshold for a pre-operative CT scan remains the optimal diagnostic modality while avoiding universal employment of computed tomography (CT). With fracture union being unaffected by implant choice, authors suggest that anatomical fixation of the femoral neck is of paramount importance followed by restoration of the length, alignment and rotation of the femoral shaft, and the implant selection primarily depends on surgeon's experience and the pattern of injury.
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Fraturas do Fêmur , Fraturas do Colo Femoral , Fixação Intramedular de Fraturas , Humanos , Fraturas do Colo Femoral/cirurgia , Colo do Fêmur , Centros de Traumatologia , Fraturas do Fêmur/cirurgia , Fixação de Fratura , Estudos RetrospectivosRESUMO
PURPOSE: To present a radiographic analysis of the anatomy of the lumbar plexus and retroperitoneal blood vessels with respect to psoas morphology and safe working zones (SWZ) for LLIF. METHODS: A retrospective radiographic analysis of 158 MRI scans was performed. Selected morphometric measurements were performed at L1-L2, L2-L3, L3-L4 and L4-L5 levels: disc anteroposterior distance, psoas anteroposterior distance, lumbar plexus-anterior disc distance, lumbar plexus-anterior psoas distance, vena cava-anterior disc distance and calculation of SWZ in psoas on both left and right sides. The morphometric measurements were analysed for differences with sex and the level. RESULTS: All the morphometric parameters differed significantly at all levels between males and females. The SWZ was significantly wider on the left side compared to the right-at L2-L3, L3-L4 and L4-L5 levels in females and at L3-L4 and L4-L5 levels in males. The SWZ at L4-L5 was narrowest on both left and right sides-and significantly reduced compared to other levels. 6.9% patients had a SWZ > 20 mm on the left side, and 44.9% patients had SWZ < 20 mm on the right side. With caudal progression of levels, the lumbar plexus and psoas muscle migrated anteriorly and the vena cava/right iliac vein migrated posteriorly. CONCLUSION: A detailed study of preoperative MRI scans should be carried out in patients planned for LLIF-particularly, at L4-L5 level and in females. A left-sided trans-psoas approach is safer to perform compared to the right side-a right-sided approach should be avoided at L4-L5 considering the narrow SWZ at that level.
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Vértebras Lombares , Fusão Vertebral , Estudos Transversais , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Masculino , Músculos Psoas/diagnóstico por imagem , Estudos Retrospectivos , Fusão Vertebral/efeitos adversosRESUMO
INTRODUCTION: Most studies of transcranial direct current stimulation (tDCS) for motor deficits in patients with stroke administered few sessions of tDCS and with low current amplitude. METHODS: During 2015 to 2019, we randomized 60 inpatients with ischemic/hemorrhagic stroke and motor deficits to true or sham tDCS. Transcranial direct current stimulation was administered at 2- to 3-mA current strength, twice daily, 6 days a week, for 2 weeks; anode and cathode were placed over ipsilesional and contralesional motor cortices, respectively. All patients received individualized motor and cognitive rehabilitation. Motor outcomes were assessed 1 day before and 1 day after the tDCS course using the Fugl-Meyer Assessment, the Jebson-Taylor Hand Function Test, and the Barthel index (all coprimary outcomes). Mood and cognition were also assessed. Motor outcomes were compared between groups using age, baseline scores, and latency to treatment as covariates. The study was prospectively registered (CTRI/2017/01/007733). RESULTS: The mean age of the patients was 46.9 years. The sample was 73.3% male. Six patients did not complete the study. The covariates were significantly related to motor outcomes. Although all patients showed motor improvements, after adjusting for covariates, tDCS was not superior to sham treatment on any motor, mood, or cognitive outcome. Laterality of hemispheric lesion influenced spatial but not motor outcomes with tDCS. One true tDCS patient developed blistering under the anode and was withdrawn from the study; 3 more reported transient itching during sessions. CONCLUSIONS: An intensive course of tDCS, as delivered in this study, does not improve motor, mood, and cognitive outcomes in ischemic/hemorrhagic stroke in patients undergoing individualized rehabilitation. The study provides important leads for directions for future research.
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Eletroconvulsoterapia , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Estimulação Transcraniana por Corrente Contínua , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recuperação de Função Fisiológica , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/terapia , Resultado do Tratamento , Extremidade SuperiorRESUMO
Spasticity is a common manifestation of many upper motor neuron lesions such as stroke, traumatic brain injury, and multiple sclerosis. In some cases, spastic fingers in the hand press hard into the palm, resulting in skin breakdown and atypical pressure ulcerations. We treated 10 such patients living in the nursing homes with long-standing treatment-resistant hand ulcers in our spasticity clinic first, with Botulinum toxin A (BoNTA) injection into the spastic muscles followed by dressing, splinting, and hand therapy. These ulcers failed to respond to standard treatment, causing significant pain, offensive smell, increased carer burden, and difficulty in maintaining hygiene as hands could barely be opened for dressing and therapy. We noted complete healing of ulcers with significant improvement in the following outcome measures-Modified Ashworth Scale for spasticity, Visual Analog Scale for pain, pressure ulcer grading for the ulcers, Fingertip to Palm distance for hand opening, Carer Burden Scale, and in the Goal Attainment Scale pre, 4 weeks, and 3 months postinjection with P values of .003, .003, .004, .005, .004, and .004, respectively. Reducing spasticity with BoNTA should be the first step in treating hand ulcerations caused by focal spasticity, followed by dressing, splinting, and hand therapy.
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Toxinas Botulínicas Tipo A/uso terapêutico , Mãos , Espasticidade Muscular/complicações , Espasticidade Muscular/tratamento farmacológico , Fármacos Neuromusculares/uso terapêutico , Úlcera Cutânea/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Bandagens , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Úlcera Cutânea/etiologia , Úlcera Cutânea/patologia , CicatrizaçãoRESUMO
We report a rare case of post-traumatic cutaneous diphtheria in a patient referred from a hospital in rural India. The diagnosis of cutaneous diphtheria was confirmed by the isolation of Corynebacterium diphtheriae cultured from the ulcer of the leg, along with Staphylococcus aureus, Streptococcus pyogenes, and Arcanobacterium haemolyticum. The patient was kept on isolation and treated with erythromycin for 14 days without antitoxin. He was discharged when his subsequent cultures turned out to be negative. Chemoprophylaxis was also given to his family members. Such a case highlights the revisiting of vaccination strategies and the role of cutaneous carriers in transmission of this deadly disease.
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Antibacterianos/uso terapêutico , Corynebacterium diphtheriae/isolamento & purificação , Difteria/diagnóstico , Eritromicina/uso terapêutico , Dermatopatias/diagnóstico , Adulto , Difteria/classificação , Difteria/microbiologia , Humanos , Índia , Masculino , Dermatopatias/microbiologia , Resultado do TratamentoRESUMO
BACKGROUND: Post-stroke lower limb spasticity (PSLLS) has a prevalence of 28-37%. PSLLS can cause difficulty in walking and reduce quality of life (QOL). Post stroke spasticity impairs the ability to intervene to improve walking ability. Botulinum Toxin A (BT) is an effective intervention for focal spasticity, but its use is currently restricted in many countries by their reimbursement system stating that the evidence for improvement in walking and quality of life (QOL) is not robust for treatment in the lower limb. This randomized control trial (RCT) will investigate the effectiveness of BT in modifying spasticity, and improving functioning (mobility, walking, activities of daily living (ADL's) and QOL. METHODS/DESIGN: A double-blind placebo-controlled trial injection will assess the effect of BT compared with a placebo (normal saline) in a sample of n = 94 patients. Following treatment of spasticity measured by Modified Ashworth Scale (MAS), the primary outcome of gait velocity will be measured by i) Gait Rite (Electronic Walkway); ii) walking by 2 Min Walk Test; iii) balance by Berg Balance Scale; mobility by iv) Timed Up and Go (TUG); v) lower limb function by ABILICO; vi) patient related goal by Goal Attainment Scale (GAS); vii) QOL by SF 12 (Rand version); viii) activities of daily living by the Functional Autonomy Measurement System (SMAF). There will be an associated health economic analysis. DISCUSSION: The study methodology is based on our systematic review 2026 studies, which concluded the evidence for improving mobility following use of BT to reduce spasticity was not robust. The results of this study could establish the use of BT in improving gait and lower limb function in PSLLS. This study could provide the evidence needed for reimbursement schemes to consider and changes to its funding policy for BT in PSLLS. TRIAL REGISTRATION: The trial is registered with the Australia New Zealand Clinical Trails Registry (ANZCTR)- ANZCTRN12617001603303 . Registered 07/12/2017.
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Toxinas Botulínicas Tipo A/uso terapêutico , Espasticidade Muscular/tratamento farmacológico , Fármacos Neuromusculares/uso terapêutico , Qualidade de Vida , Acidente Vascular Cerebral/complicações , Atividades Cotidianas , Idoso , Método Duplo-Cego , Feminino , Humanos , Extremidade Inferior/fisiopatologia , Masculino , Pessoa de Meia-Idade , Espasticidade Muscular/etiologia , Projetos de Pesquisa , CaminhadaRESUMO
BACKGROUND: Stroke leads to devastating impact on health as well as quality of life making it one of the leading causes of disability. Restoring the functions of upper extremities after ischemic (ISC) stroke is one of the challenges for rehabilitation. Lack of trained professionals and accessibility to rehabilitation centers are limited in many counties. Constraint induced movement therapy (CIMT) has been practiced in regaining the functional activity following stroke. CIMT can be practiced with minimum clinical set up which makes it cost effective. However, the neural plasticity mechanism underlying the recovery with CIMT is not well understood. METHODS: In the current study, we sought to investigate the extent to which CIMT helps in ameliorating neurological deficits in rat model of ISC stroke, induced by Endothelin-1 (ET-1). As well as to understand the cortical plasticity with Golgi-Cox staining and interhemispheric interaction with biotinylated dextran amine (BDA) following CIMT. Neurological deficits were identified within 24 hours of ET-1 infusion. RESULTS: CIMT restored the impaired skilled movements after ISC stroke and improved the quality of fine movements. Golgi-Cox staining showed significant decrease in dendritic arborization in the injured motor cortex following ISC stroke. CIMT was efficient in reversing this effect as indicated by increased dendritic arborization especially in layer III pyramidal neurons. Also, the stroke induced asymmetry in dendritic length across both hemispheres was found to be reduced with CIMT. BDA tracing showed a re-establishment of the axonal connections between the hemispheres after CIMT. CONCLUSIONS: Implications of CIMT can be one of the promising and low cost rehabilitative technique for the individuals with upper limb movement deficits.
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Terapia por Exercício/métodos , Membro Anterior/inervação , Córtex Motor/fisiopatologia , Plasticidade Neuronal , Desempenho Psicomotor , Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/terapia , Animais , Comportamento Animal , Avaliação da Deficiência , Modelos Animais de Doenças , Masculino , Córtex Motor/patologia , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/psicologia , Fatores de TempoRESUMO
Horseshoe bats have dynamic biosonar systems with interfaces for ultrasonic emission (reception) that change shape while diffracting the outgoing (incoming) sound waves. An information-theoretic analysis based on numerical and physical prototypes shows that these shape changes add sensory information (mutual information between distant shape conformations <20%), increase the number of resolvable directions of sound incidence, and improve the accuracy of direction finding. These results demonstrate that horseshoe bats have a highly effective substrate for dynamic encoding of sensory information.
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Quirópteros , Ecolocação , Ultrassom , Animais , Modelos Biológicos , Localização de SomRESUMO
Based on mesoscale lattice Boltzmann (LB) numerical simulations, we investigate the effects of viscoelasticity on the break-up of liquid threads in microfluidic cross-junctions, where droplets are formed by focusing a liquid thread of a dispersed (d) phase into another co-flowing continuous (c) immiscible phase. Working at small Capillary numbers, we investigate the effects of non-Newtonian phases in the transition from droplet formation at the cross-junction (DCJ) to droplet formation downstream of the cross-junction (DC) (Liu and Zhang, Phys. Fluids. 23, 082101 (2011)). We will analyze cases with Droplet Viscoelasticity (DV), where viscoelastic properties are confined in the dispersed phase, as well as cases with Matrix Viscoelasticity (MV), where viscoelastic properties are confined in the continuous phase. Moderate flow-rate ratios Q≈O(1) of the two phases are considered in the present study. Overall, we find that the effects are more pronounced with MV, where viscoelasticity is found to influence the break-up point of the threads, which moves closer to the cross-junction and stabilizes. This is attributed to an increase of the polymer feedback stress forming in the corner flows, where the side channels of the device meet the main channel. Quantitative predictions on the break-up point of the threads are provided as a function of the Deborah number, i.e., the dimensionless number measuring the importance of viscoelasticity with respect to Capillary forces.
RESUMO
The effects of viscoelasticity on the dynamics and break-up of fluid threads in microfluidic T-junctions are investigated using numerical simulations of dilute polymer solutions at changing the Capillary number (Ca), i.e. at changing the balance between the viscous forces and the surface tension at the interface, up to Ca ≈ 3×10(-2). A Navier-Stokes (NS) description of the solvent based on the lattice Boltzmann models (LBM) is here coupled to constitutive equations for finite extensible non-linear elastic dumbbells with the closure proposed by Peterlin (FENE-P model). We present the results of three-dimensional simulations in a range of Ca which is broad enough to characterize all the three characteristic mechanisms of break-up in the confined T-junction, i.e. squeezing, dripping and jetting regimes. The various model parameters of the FENE-P constitutive equations, including the polymer relaxation time τP and the finite extensibility parameter L2, are changed to provide quantitative details on how the dynamics and break-up properties are affected by viscoelasticity. We will analyze cases with Droplet Viscoelasticity (DV), where viscoelastic properties are confined in the dispersed (d) phase, as well as cases with Matrix Viscoelasticity (MV), where viscoelastic properties are confined in the continuous (c) phase. Moderate flow-rate ratios Q ≈ O(1) of the two phases are considered in the present study. Overall, we find that the effects are more pronounced in the case with MV, as the flow driving the break-up process upstream of the emerging thread can be sensibly perturbed by the polymer stresses.
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OBJECTIVES: To describe and compare epidemiologic characteristics and clinical outcomes of patients with nontraumatic spinal cord dysfunction according to etiology. DESIGN: Retrospective, multicenter open-cohort case series. SETTING: Spinal rehabilitation units (SRUs) in 9 countries. PARTICIPANTS: Patients (N=956; men, 60.8%; median age, 59.0y [interquartile range, 46-70.0y]; paraplegia, n=691 [72.3%]) with initial onset of spinal cord dysfunction consecutively admitted between January 1, 2008, and December 31, 2010. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Etiology of spinal cord dysfunction, demographic characteristics, length of stay (LOS) in rehabilitation, pattern of spinal cord dysfunction onset, discharge destination, level of spinal cord damage, and the American Spinal Injury Association Impairment Scale (AIS) grade on admission and discharge. RESULTS: The most common etiologies were degenerative (30.8%), malignant tumors (16.2%), infections (12.8%), ischemia (10.9%), benign tumors (8.7%), other vascular (8.5%), and other conditions (12.1%). There were major differences in epidemiologic characteristics and clinical outcomes of patients with different etiologies of spinal cord dysfunction. Paraplegia was more common in patients with a malignant tumor and vascular etiologies, while tetraplegia was more common in those with a degenerative etiology, a benign tumor, and infections. Patients with a malignant tumor tended to have the shortest LOS in the SRU, while those with a vascular etiology tended to have the longest. Except for patients with a malignant tumor, all patient groups had a significant change in their AIS grade between admission and discharge. CONCLUSIONS: This international study of spinal cord dysfunction showed substantial variation between the different etiologies regarding demographic and clinical characteristics, including changes in AIS between admission and discharge.
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Pacientes Internados , Doenças da Medula Espinal/etiologia , Doenças da Medula Espinal/reabilitação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Avaliação da Deficiência , Feminino , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Doenças da Medula Espinal/epidemiologia , Doenças da Medula Espinal/fisiopatologiaRESUMO
OBJECTIVES: To compare the clinical, balance, and radiological profile of progressive supranuclear palsy (PSP) of Richardson type (PSP-R) and Parkinsonian type (PSP-P). MATERIALS AND METHODS: Twenty-nine patients with PSP (PSP-R: 17, PSP-P: 12) satisfying the probable/possible National Institute of Neurological Disorders and Stroke-PSP criteria were recruited and assessed with Unified Parkinson's Disease Rating Scale-III, PSP rating scale (PSPRS), Berg balance scale (BBS), Tinetti performance-oriented mobility assessment gait and total (TPG and TPT) score, dynamic posturography (DP), and magnetic resonance imaging. Data were compared with 30 age- and gender-matched healthy controls. RESULTS: The mean ages of PSP-R, PSP-P, and controls were comparable (62.5 ± 6.6, 59 ± 8.9, and 59.8 ± 7.6 years). The PSP group had significantly poor DP scores and more radiological abnormalities than controls. The PSPRS, TPG, and TPT scores were significantly more impaired in PSP-R compared to PSP-P (P = 0.045, P = 0.031, and P = 0.037, respectively). In DP, the limits of overall stability were most significant (P < 0.001) and PSP-R had lower scores. PSP-R compared to PSP-P had more often "Humming Bird" sign (P < 0.001), "Morning Glory" sign (P < 0.008), and generalized cortical atrophy (P < 0.001). The area of midbrain (P < 0.002) and midbrain/pons ratio (P < 0.013) was significantly lower in PSP-R. In PSP-P, the overall balance index significantly correlated with BBS, TPG, and TPT (r = -0.79, P = 0.002; r = -0.772, P = 0.003; and r = -0.688, P = 0.013) and the midbrain axial anterior-posterior diameter significantly correlated with the TPG and TPT (r = 0.74, P = 0.01; r = 0.66, P = 0.018). CONCLUSIONS: While balance and radiological abnormalities were more severe in PSP-R, the qualitative and quantitative measurements of severity of balance in PSP-P rather than PSP-R was a better reflection of the pathology of the midbrain.
Assuntos
Imageamento por Ressonância Magnética , Mesencéfalo/patologia , Paralisia Supranuclear Progressiva/diagnóstico por imagem , Idoso , Atrofia , Feminino , Humanos , Masculino , Mesencéfalo/diagnóstico por imagem , Pessoa de Meia-Idade , Paralisia Supranuclear Progressiva/patologiaRESUMO
BACKGROUND: There are currently no data on the efficacy of angiotensin-converting enzyme inhibitors (ACEis) in Hispanic patients with heart failure (HF) and reduced ejection fraction (HFrEF). We aimed to investigate the effect of adding ACEis to beta-blockers on mortality and hospitalization for HF exacerbation in patients with HFrEF stratified by race/ethnicity. METHODS AND RESULTS: From Montefiore Medical Center's 3 large hospitals, 618 consecutive patients with HFrEF (left ventricular ejection fraction [LVEF] <35%) who were on a beta-blocker were retrospectively identified. Patients were divided into 2 groups based on whether or not they were on an ACEi for 24 consecutive months. Propensity score matching including all baseline characteristics was performed and patients were then categorized into 3 groups: African Americans, Hispanics, and Whites/Caucasians. We evaluated 2-year all-cause mortality and 2-year hospitalization for HF exacerbation. Of 618 patients, 66% were categorized as ACEi and 34% as no-ACEi. Four hundred twenty-seven patients were matched 2:1 between the ACEi and no-ACEi groups. After matching, overall 2-year mortality and hospitalization rates were similar between ACEi and no-ACEi (12.4% vs 17.8%, hazard ratio [HR] 0.66, 95% confidence interval [CI] 0.38-1.16; P = .14; and 8.1% vs 9.5%, HR 0.84, 95% CI 0.44-1.60; P = .6; respectively). After stratifying patients based on race/ethnicity, ACEi demonstrated a lower 2-year mortality compared with no-ACEi in Hispanics (9.8% vs 28.4%, HR 0.33, 95% CI 0.13-0.87; P = .018) but not in African Americans (17.0% vs 11.8%, HR 0.94, 95% CI 0.34-2.65; P = .91) or Whites (9.2% vs 10.3%, HR 0.89, 95% CI 0.29-2.74; P = .83). Two-year hospitalization was not different between ACEi and no-ACEi in Hispanics, African Americans, or Whites (all P = NS). In multivariate analysis, ACEi therapy was an independent predictor of lower 2-year mortality (HR 0.33, 95% CI 0.12-0.89; P = .028) in Hispanics only. CONCLUSIONS: In this retrospective propensity-matched study of patients with HFrEF who were on a beta-blocker, ACEi therapy was associated with greater mortality reduction in Hispanic patients compared with African Americans and Whites. These findings need to be confirmed in large national studies that include a significant fraction of Hispanic patients.