RESUMEN
Ultra-high-precision single-point diamond turning (SPDT) is the state-of-the-art machining technology for the advanced manufacturing of critical components with an optical surface finish and surface roughness down to one nanometer. One of the critical factors that directly affects the quality of the diamond-cutting process is the cutting force. Increasing the cutting force can induce tool wear, increase the cutting temperature, and amplify the positioning errors of the diamond tool caused by the applied cutting force. It is important to measure the cutting force during the SPDT process to monitor the tool wear and surface defects in real time. By measuring the cutting force in different cutting conditions, the optimum cutting parameters can be determined and the best surface accuracies with minimum surface roughness can be achieved. In this study a smart cutting tool for in-process force measurement and nanopositioning of the cutting tool for compensating the displacements of the diamond tool during the cutting process is designed and analyzed. The proposed smart cutting tool can measure applied forces to the diamond tool and correct the nanometric positioning displacements of the diamond tool in three dimensions. The proposed cutting tool is wireless and can be used in hybrid and intelligent SPDT platforms to achieve the best results in terms of optical surface finish. The simulation results are shown to be almost consistent with the results of the derived analytical model. The preliminary results pave the way for promising applications of the proposed smart cutting tool in SPDT applications in the future.
RESUMEN
Distraction Osteogenesis (DO) is an emerging technique for reconstruction of bone tissue in different body zones including mandible, tibia, hand, and foot. The application of DO technique in reconstruction of bone tissue has shown promising results compared to conventional reconstruction techniques, including bone grafting, prosthetics, and the vascularized flap. Mechanical distractors, with intermittent manual activation by the user, have been widely used in different reconstruction applications. Recently, automatic devices have been developed and used for enabling reconstruction applications using continuous DO technique. These devices can generate a continuous force while continuously moving the bone segment with high movement accuracy and distraction rate. In the continuous DO technique, by using a continuous force, instead of applying intermittent manual forces generated by the operator, better results in a shorter treatment could be obtained. Previous studies have shown that current automatic devices could positively influence bone tissue regeneration while obtaining promising results in the reconstruction of mandible. In hand reconstruction applications (HRA), only manual and mechanical mechanisms, using discontinuous DO technique, have been developed and used. In this research, an automatic device for HRA, using continuous DO technique, has been designed and developed. The proposed system is capable of generating a continuous distraction force for moving the bone segment in a fully automatic DO process. This novel reconstruction approach can be used for lengthening and reconstruction of different hand bones, including distal, middle, proximal, metacarpal, and carpal bones. In HRA, by using the proposed automatic continuous distractor better results in a shorter treatment period, compared to manual DO solutions, can be achieved.
Asunto(s)
Osteogénesis por Distracción , Procedimientos de Cirugía Plástica , Regeneración Ósea , Trasplante Óseo , Mandíbula/cirugía , Osteogénesis , Osteogénesis por Distracción/métodosRESUMEN
INTRODUCTION: Birth trauma rates in term of neonates is a quality measure used by the Joint Commission. In the United States birth trauma rates occurs at a rate of 37 per 1000 live births and are on the decline. However, this decline has been significantly lower among term neonates born in rural facilities. There is a critical lack of evidence toward the influence geographical risk factors has on birth trauma rates for neonatal patients. We sought to measure rural community and hospital characteristics associated with birth trauma. METHODS: A retrospective longitudinal study design was used to examine inpatient medical discharge data across 103 hospitals of neonates at birth from 2013 to 2018. Discharge data was linked to the American Hospital Association annual survey. We used a multi-level mixed effect model to investigate the relationship between individual and hospital-level attributes associated with increased risk of birth trauma among neonatal patients. RESULTS: We found that rural hospitals were 3.99 times (p < 0.001) more likely to experience higher birth trauma than urban hospitals. Medium sized hospitals were 2.11 times (p < 0.001) more likely to experience higher birth trauma. Hospitals who indicate having a safety culture were more likely (p < 0.05) to have high rates of birth trauma. DISCUSSION: Neonates born at rural hospitals, were more likely to experience a birth-related injury. Policy strategies focusing on improving health care quality in rural areas are critical to mitigating this increased risk of birth trauma. Further research is required to assess how physician characteristics may impact birth trauma rates.
Asunto(s)
Hospitales Rurales , Hospitales Urbanos , Femenino , Florida/epidemiología , Humanos , Recién Nacido , Estudios Longitudinales , Estudios Retrospectivos , Estados Unidos/epidemiologíaAsunto(s)
COVID-19 , Pandemias , Humanos , Pandemias/prevención & control , COVID-19/epidemiología , Sudáfrica/epidemiología , SARS-CoV-2RESUMEN
Distraction Osteogenesis (DO) is an emerging limb lengthening method for the reconstruction of the hard tissue and the surrounding soft tissue, in different human body zones. DO plays an important role in treating bone defects in Maxillofacial Reconstruction Applications (MRA) due to reduced side effects and better formed bone tissue compared to conventional reconstruction methods i.e. autologous bone graft, and alloplast implantation. Recently, varying techniques have been evaluated to enhance the characteristics of the newly formed tissues and process parameters. Promising results have been shown in assisting DO treatments while benefiting bone formation mechanisms by using physical stimulation techniques, including photonic, electromagnetic, electrical, and mechanical stimulation technique. Using assisted DO techniques has provided superior results in the outcome of the DO procedure compared to a standard DO procedure. However, DO methods, as well as assisting technologies applied during the DO procedure, are still emerging. Studies and experiments on developed solutions related to this field have been limited to animal and clinical trials. In this review paper, recent advances in physical stimulation techniques and their effects on the outcome of the DO treatment in MRA are surveyed. By studying the effects of using assisting techniques during the DO treatment, enabling an ideal assisted DO technique in MRA can be possible. Although mentioned techniques have shown constructive effects during the DO procedure, there is still a need for more research and investigation to be done to fully understand the effects of assisting techniques and advanced technologies for use in an ultimate DO procedure in MRA.
Asunto(s)
Osteogénesis por Distracción , Animales , Trasplante Óseo , Humanos , Osteogénesis , Estimulación FísicaRESUMEN
African American women, in particular, have learned to navigate through a food consumption landscape that purposefully, and often aggressively, limits their choices and stigmatizes their resulting physical appearance, and renders them collectively unattractive and unworthy. While American women are challenged to subscribe to traditional slim body standards, a faction of Americans have differing opinions. African American (AA) women celebrate larger body types and defy weight stigma. When African Americans make food choices, taste and cost are not the only factors influencing those choices; the cultural role of food is also considered. We conducted semi-structured interviews with 12 African American girls to identify some of the consequences of this consumption practice that challenges what we argue is a hegemonic taste regime surrounding body size. This work further elucidates the ways in which the African American community has operationalized the concept of cultural capital around the issues of body image to create what we suggest is a type of emotional well-being. In addition to uncovering marketing channels promoting anti-obesity campaigns that would be more likely to capture their attention, our findings also reveal that AA girls embrace shapely bodies, despite not necessarily having one themselves, and overall possess a more positive body image than their Caucasian peers. Having shapely bodies was deemed more attractive among romantic interests and acceptable overall in the AA community regardless of the associated health risks associated with consuming unhealthy foods.
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Negro o Afroamericano , Población Blanca , Imagen Corporal , Femenino , Preferencias Alimentarias , Humanos , ObesidadRESUMEN
Patient experience has been one of many significant drivers in determining hospitals' performance. Multivariate logistic regression was used to investigate the factors that impacted patients' likelihood to give top ratings for the overall hospital experience. Large hospitals with a lower percentage of Medicare/Medicaid patients and existing electronic health record system were more likely to receive top ratings. White, female patients with lower education levels were more likely to give top ratings for all quality domains (nurse, doctor, staff, and environment). All quality domains had positive impacts on patient experience, with the nursing domain being the most influential factor.