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Building on work by Stallings, Jaco, and Hempel in three dimensions and a more recent four-dimensional analog by Abrams, Kirby, and Gay, we show how the splitting homomorphism and group trisection constructions can be extended to functors between appropriate categories. This further enhances the bridge between smooth four-dimensional topology and the group theory of free and surface groups.
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Given a diagram for a trisection of a 4-manifold X, we describe the homology and the intersection form of X in terms of the three subgroups of [Formula: see text] generated by the three sets of curves and the intersection pairing on [Formula: see text] This includes explicit formulas for the second and third homology groups of X as well an algorithm to compute the intersection form. Moreover, we show that all [Formula: see text]-trisections admit "algebraically trivial" diagrams.
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Unicompartmental knee arthroplasty (UKA) in isolated medial or lateral osteoarthritis leads to good clinical results. However, revision rates are higher in comparison to total knee arthroplasty (TKA). One reason is suboptimal fitting of conventional off-the-shelf prostheses, and major overhang of the tibial component over the bone has been reported in up to 20% of cases. In this retrospective study, a total of 537 patient-specific UKAs (507 medial prostheses and 30 lateral prostheses) that had been implanted in 3 centers over a period of 10 years were analyzed for survival, with a minimal follow-up of 1 year (range 12 to 129 months). Furthermore, fitting of the UKAs was analyzed on postoperative X-rays, and tibial overhang was quantified. A total of 512 prostheses were available for follow-up (95.3%). Overall survival rate (medial and lateral) of the prostheses after 5 years was 96%. The 30 lateral UKAs showed a survival rate of 100% at 5 years. The tibial overhang of the prosthesis was smaller than 1 mm in 99% of cases. In comparison to the reported results in the literature, our data suggest that the patient-specific implant design used in this study is associated with an excellent midterm survival rate, particularly in the lateral knee compartment, and confirms excellent fitting.
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There are few materials that are broadly used for fabricating optical metasurfaces for visible light applications. Gallium phosphide (GaP) is a material that, due to its optical properties, has the potential to become a primary choice but due to the difficulties in fabrication, GaP thin films deposited on transparent substrates have never been exploited. In this article we report the design, fabrication, and characterization of three different amorphous GaP metasurfaces obtained through sputtering. Although the material properties can be further optimized, our results show the potential of this material for visible applications making it a viable alternative in the material selection for optical metasurfaces.
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Gardner-Diamond syndrome (GDS) is a psychological and dermatologic syndrome involving painful, ecchymotic, purpuric lesions that typically appear after a period of stress or minor trauma. This syndrome most commonly occurs in young women, though it has also been less commonly reported in men and adolescents. It is an uncommon condition and appropriate diagnosis is important to properly manage symptoms and minimize risks to patients. Here report a case of GDS presenting in a woman with common variable immunodeficiency (CVID), which, to the best of our knowledge, is not a comorbid condition that has previously been reported in correlation with GDS.
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Airway dendritic cells (DCs) control pulmonary immune responses to inhaled particles. However, the profile of function-associated surface molecules on airway DCs in smokers is unknown. In this study, function-associated surface molecules were analyzed using four-color flow cytometry on myeloid DCs (mDCs) in bronchoalveolar lavage fluid (BALF) of cigarette smokers and never-smokers. Furthermore, the lung function was assessed directly before bronchoscopy in all participants. There was a 7-fold increase in total cell numbers in BALF of smokers, as compared with never-smokers. The percentage of mDCs among BALF cells and the expression of the maturation marker CD83 on mDCs did not differ between smokers and never-smokers. However, there was a strong increase in the expression of Langerin and CD1a (markers of Langerhans cells) on mDCs of smokers. Furthermore, mDCs of smokers were characterized by an increased expression of antigen presentation markers such as CD80 and CD86. By contrast, mDCs of smokers displayed a decreased expression of the lymph node homing receptor CCR7, as compared with mDCs of never-smokers. Decreased expression of CCR7 on mDCs, but not any of the other surface molecules studied, was specifically associated with airway obstruction and pulmonary hyperinflation in smokers. In conclusion, our data suggest that smoking affects the expression profile of function-associated surface molecules on airway mDCs. We provide the first evidence that a reduced CCR7 expression on airway mDCs is associated with airflow limitation in smokers.
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Líquido del Lavado Bronquioalveolar/citología , Células Dendríticas , Pulmón/citología , Fumar , Adulto , Antígenos CD/metabolismo , Antígeno B7-1/metabolismo , Antígeno B7-2/metabolismo , Biomarcadores/metabolismo , Linaje de la Célula , Células Dendríticas/citología , Células Dendríticas/metabolismo , Femenino , Citometría de Flujo , Humanos , Inmunoglobulinas/metabolismo , Masculino , Glicoproteínas de Membrana/metabolismo , Persona de Mediana Edad , Receptores CCR7/metabolismo , Antígeno CD83RESUMEN
Purpose The purpose of this paper is to evaluate the effectiveness of negotiation training delivered to senior clinicians, managers and executives, by exploring whether staff members implemented negotiation skills in their workplace following the training, and if so, how and when. Design/methodology/approach This is a qualitative study involving face-to-face interviews with 18 senior clinicians, managers and executives who completed a two-day intensive negotiation skills training course. Interviews were transcribed verbatim, and inductive interpretive analysis techniques were used to identify common themes. Research setting was a large tertiary care hospital and health service in regional Australia. Findings Participants generally reported positive affective and utility reactions to the training, and attempted to implement at least some of the skills in the workplace. The main enabler was provision of a Negotiation Toolkit to assist in preparing and conducting negotiations. The main barrier was lack of time to reflect on the principles and prepare for upcoming negotiations. Participants reported that ongoing skill development and retention were not adequately addressed; suggestions for improving sustainability included provision of refresher training and mentoring. Research limitations/implications Limitations include self-reported data, and interview questions positively elicited examples of training translation. Practical implications The training was well matched to participant needs, with negotiation a common and daily activity for most healthcare professionals. Implementation of the skills showed potential for improving collaboration and problem solving in the workplace. Practical examples of how the skills were used in the workplace are provided. Originality/value To the authors' knowledge, this is the first international study aimed at evaluating the effectiveness of an integrative bargaining negotiation training program targeting executives, senior clinicians and management staff in a large healthcare organization.
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Conducta Competitiva , Conducta Cooperativa , Administradores de Instituciones de Salud/educación , Personal de Salud/educación , Negociación , Adulto , Australia , Femenino , Humanos , Entrevistas como Asunto , Masculino , Persona de Mediana Edad , Evaluación de Programas y Proyectos de Salud , Investigación Cualitativa , Adulto JovenRESUMEN
Metasurfaces have facilitated the replacement of conventional optical elements with ultrathin and planar photonic structures. Previous designs of metasurfaces were limited to small deflection angles and small ranges of the angle of incidence. Here, we have created two types of Si-based metasurfaces to steer visible light to a large deflection angle. These structures exhibit high diffraction efficiencies over a broad range of angles of incidence. We have demonstrated metasurfaces working both in transmission and reflection modes based on conventional thin film silicon processes that are suitable for the large-scale fabrication of high-performance devices.
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Complex problems often require coordinated group effort and can consume significant resources, yet our understanding of how teams form and succeed has been limited by a lack of large-scale, quantitative data. We analyse activity traces and success levels for approximately 150 000 self-organized, online team projects. While larger teams tend to be more successful, workload is highly focused across the team, with only a few members performing most work. We find that highly successful teams are significantly more focused than average teams of the same size, that their members have worked on more diverse sets of projects, and the members of highly successful teams are more likely to be core members or 'leads' of other teams. The relations between team success and size, focus and especially team experience cannot be explained by confounding factors such as team age, external contributions from non-team members, nor by group mechanisms such as social loafing. Taken together, these features point to organizational principles that may maximize the success of collaborative endeavours.
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ETHICISTS RECOMMEND THAT investigators assess subjects' comprehension prior to accepting their consent as valid. Because children represent an at-risk population, ensuring adequate comprehension in pediatric research is vital. We surveyed all corresponding authors of research articles published over a six-month period in five leading adult and pediatric journals. Our goal was to assess how often subject's comprehension or decisional capacity was assessed in the consent process, whether there was any difference between adult and pediatric research projects, and the rate at which investigators use formal or validated tools to assess capacity. Responses from 102 authors were analyzed (response rate 56%). Approximately two-thirds of respondents stated that they assessed comprehension or decisional capacity prior to accepting consent, and we found no difference between adult and pediatric researchers. Nine investigators used a formal questionnaire, and three used a validated tool. These findings suggest that fewer than expected investigators assess comprehension and decisional capacity, and that the use of standardized and validated tools is the exception rather than the rule.
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This study evaluates the biogeochemical changes that occur when recharge water comes in contact with a reduced aquifer. It specifically addresses (1) which reactions occur in situ, (2) the order in which these reactions will occur if terminal electron acceptors (TEAs) are introduced simultaneously, (3) the rates of these reactions, and (4) the roles of the aqueous and solid-phase portions of the aquifer. Recharge events of waters containing various combinations of O2, NO3, and SO4 were simulated at a shallow sandy aquifer contaminated with waste fuels and chlorinated solvents using modified push-pull tests to quantify rates. In situ rate constants for aerobic respiration (14.4 day(-1)), denitrification (5.04-7.44 day(-1)), and sulfate reduction (4.32-6.48 day(-1)) were estimated. Results show that when introduced together, NO3 and SO4 can be consumed simultaneously at similar rates. To distinguish the role of aqueous phase from that of the solid phase of the aquifer, groundwater was extracted, amended with NO3 and SO4, and monitored overtime. Results indicate that neither NO3 nor SO4 was reduced during the course of the aqueous-phase study, suggesting that NO3 and SO4 can behave conservatively in highly reduced water. It is clear that sediments and their associated microbial communities are important in driving redox reactions.