The Effect of Powder Re-Use on the Coalescence Behaviour and Isothermal Crystallisation Kinetics of Polyamide 12 within Powder Bed Fusion.

Polymer powder bed fusion (PBF) is becoming increasingly popular for the fabrication of lightweight, high-performance parts, particularly for medical and aerospace applications. This study investigates the effect of powder re-use and material aging on the coalescence behaviour, melt flowability, and isothermal crystallisation kinetics of polyamide-12 (PA-12) powder. With increased powder re-use, a progressive reduction in melt flowability and material coalescence is observed; at 200 °C, the particle consolidation time increases from 15 s in virgin powder to 180 s in powder recovered from build 6. The observed changes in the behaviour of PA-12 were attributed to polycondensation and cross-linking; these aging phenomena also create structural defects, which hinder the rate and extent of primary crystallisation. At an isothermal crystallisation temperature of 165 °C, the crystallisation half-time increased from 12.78 min in virgin powder to 23.95 min in powder re-used across six build cycles. As a result, the commonly used Avrami model was found to be unsuitable for modelling the crystallisation behaviour of aged PA-12 powder, with the co-efficient of determination (R2) reducing from >0.995 for virgin powder to as low as 0.795 for re-used powder. On the other hand, an alternative method, the Hay model, is able to successfully track full phase transformation within re-used powder (R2 > 0.99). These results highlight the importance of selecting the most appropriate model for analysing the crystallisation kinetics of PA-12 powder re-used across multiple build cycles. This understanding is crucial for obtaining the strong mechanical properties and dimensional precision required for the fabrication of functional, end-use parts within PBF.

Evaluation of ventricular-vascular coupling with critical care metrics: An in silico approach.

Mean arterial pressure and cardiac output provide insufficient guidance for the management of intraoperative hypotension (IOH). In silico models offer additional insights into acute changes in hemodynamic parameters that may be encountered during IOH. A computational model (CM) generated parameters quantifying ventricular-vascular coupling, and pressure-volume construct across levels of aortic compliance (CA ). We studied how a loss from normal-to-stiff CA impacts critical care metrics of hemodynamics during vascular occlusion. Pulse pressure (PP), end-systolic pressure (Pes ), arterial compliance (Art-ca), arterial elastance (Art-ea), and dynamic arterial elastance (Eadyn), along mechanical efficiency (ME) were measured at five levels of CA . A loss in CA impacted all variables. During steady-state conditions, PP, Pes , and stroke work increased significantly as CA decreased. Art-ca decreased and Art-ea increased similarly; Eadyn increased and ME decreased. During a decrease in preload across all CA levels, arterial dynamics measures remained linear. The CM demonstrated that a loss in CA impacts measures of arterial dynamics during steady-state and transient conditions and the model demonstrates that critical care metrics are sensitive to changes in CA . While Art-ca and Art-ea were sensitive to changes in preload, Eadyn did not change.

Provider perspectives on equity in use of mobile health autism screening tools.

LAY ABSTRACT: Families may find information about autism online, and health care and education providers may use online tools to screen for autism. However, we do not know if online autism screening tools are easily used by families and providers. We interviewed primary care and educational providers, asking them to review results from online tools that screen for autism. Providers had concerns about how usable and accessible these tools are for diverse families and suggested changes to make tools easier to use.

Preparing for the PICU: A Qualitative Study of Residents as They Prepare for Their First Pediatric Critical Care Rotation.

Learning critical care medicine in the pediatric intensive care unit (PICU) can be stressful. Through semistructured interviews ( n = 16), this study explored the emotions, perceptions, and motivations of pediatric medicine (PM) and emergency medicine (EM) residents, as they prepared for their first PICU rotation. Qualitative data were collected and analyzed using the grounded theory method. Three resultant themes emerged: (1) residents entered the PICU with a range of intense emotions and heightened expectations; (2) they experienced prior history of psychologically traumatic learning events (adverse learning experiences or ALEs); and (3) informed by ALEs, residents prepared for their rotation by focusing heavily on their most basic level of physiological needs and adopting a survival mindset prior to the start of the rotation. These three themes led to a substantive, or working, theory that ALE-associated events may affect how residents approach upcoming learning opportunities. Consequently, adapting a trauma-informed approach as a component of medical education may improve resident learning experiences in the PICU and beyond.

Reduction of nemo-like kinase increases lysosome biogenesis and ameliorates TDP-43-related neurodegeneration.

Protein aggregation is a hallmark of many neurodegenerative disorders, including amyotrophic lateral sclerosis (ALS). Although mutations in TARDBP, encoding transactive response DNA-binding protein 43 kDa (TDP-43), account for less than 1% of all ALS cases, TDP-43-positive aggregates are present in nearly all ALS patients, including patients with sporadic ALS (sALS) or carrying other familial ALS-causing (fALS-causing) mutations. Interestingly, TDP-43 inclusions are also present in subsets of patients with frontotemporal dementia, Alzheimer's disease, and Parkinson's disease; therefore, methods of activating intracellular protein quality control machinery capable of clearing toxic cytoplasmic TDP-43 species may alleviate disease-related phenotypes. Here, we identify a function of nemo-like kinase (Nlk) as a negative regulator of lysosome biogenesis. Genetic or pharmacological reduction of Nlk increased lysosome formation and improved clearance of aggregated TDP-43. Furthermore, Nlk reduction ameliorated pathological, behavioral, and life span deficits in 2 distinct mouse models of TDP-43 proteinopathy. Because many toxic proteins can be cleared through the autophagy/lysosome pathway, targeted reduction of Nlk represents a potential approach to therapy development for multiple neurodegenerative disorders.

Mobile and online consumer tools to screen for autism do not promote equity.

LAY ABSTRACT: Many parents wonder if their child might have autism. Many parents use their smartphones to answer health questions. We asked, "How easy or hard is it for parents to use their smartphones to find 'tools' to test their child for signs of autism?" After doing pretend parent searches, we found that only one in 10 search results were tools to test children for autism. These tools were not designed for parents who have low income or other challenges such as low literacy skills, low English proficiency, or not being tech-savvy.

The Effect of Physical Aging and Degradation on the Re-Use of Polyamide 12 in Powder Bed Fusion.

Powder bed fusion (PBF) is an additive manufacturing (AM) technique which offers efficient part-production, light-weighting, and the ability to create complex geometries. However, during a build cycle, multiple aging and degradation processes occur which may affect the reusability of the Polyamide 12 (PA-12) powder. Limited understanding of these phenomena can result in discarding re-usable powder unnecessarily, or the production of parts with insufficient properties, both of which lead to significant amounts of waste. This paper examines the thermal, chemical, and mechanical characteristics of PA-12 via an oven storage experiment that simulates multi jet fusion (MJF) conditions. Changes in the properties of PA-12 powder during oven storage showed two separate, time-dependent trends. Initially, differential scanning calorimetry showed a 4.2 °C increase in melting temperature (Tm) and a rise in crystallinity (Xc). This suggests that secondary crystallisation is occurring instead of, or in addition to, the more commonly reported further polycondensation process. However, with extended storage time, there were substantial reductions in Tm and Xc, whilst an 11.6 °C decrease in crystallisation temperature was observed. Fourier transform infrared spectroscopy, a technique rarely used in PBF literature, shows an increased presence of imide bonds-a key marker of thermo-oxidative degradation. Discolouration of samples, an 81% reduction in strength and severe material embrittlement provided further evidence that thermo-oxidative degradation becomes the dominant process following extended storage times beyond 100 h. An additional pre-drying experiment showed how moisture present within PA-12 can also accelerate degradation via hydrolysis.

Early Intervention Referral Information, Transmission, and Sources-A Survey of State Part C Coordinators and Analysis of Referral Forms.

OBJECTIVE: Early Intervention (EI) referral is a key connector between health care and early childhood systems serving children with developmental risks. This study aimed to describe the US network of EI referrals by answering the following: "What information is sent to EI?", "Who sends it?", and "How is it sent?" METHOD: This study combined an analysis of national document-based and website-based referral forms with a survey of state Part C Coordinators (PCCs). Data on referral forms were systematically collected from state agency websites. PCCs from 52 jurisdictions were surveyed to assess current EI referral practices. Descriptive statistics were used for responses to multiple-choice items; free-text answers were condensed into key study themes. RESULTS: EI referral forms came as e-documents (81%) or websites (35%), and 72% were in English alone. They emphasized family and referral source contact information and reason for the referral. The survey results indicated that health care (45%) sends the most referrals, followed by families (30%). EI agencies received referrals by phone (38%), electronically (23%), e-mail (17%), and fax (17%), and PCCs valued this diversity of methods. Few states received referral data directly from electronic health records (EHRs); however, PCCs hope to eventually receive referrals through websites, mobile devices, and EHRs. CONCLUSION: EI referral data flow is complex, with opportunities for loss of children to follow-up. This study describes how EI referrals occur and provides examples of how communication and access to information may be improved.

Oral Baclofen Withdrawal Resulting in Hyperactive Delirium: A Case Report.

Baclofen is used in the treatment of muscle spasms by acting as an agonist GABAB receptors. Limited case reports describing baclofen withdrawal-induced delirium have largely been demonstrated to occur upon cessation of intrathecal baclofen administration. Fewer reports have characterized the presentation from oral baclofen withdrawal. We describe a case of a patient, MM, who presented with hyperactive delirium with various, associated, behavioral, perceptual, cognitive, and movement disturbances following abrupt withdrawal of oral baclofen. Symptomatic management of occurring during the withdrawal state with antipsychotics and benzodiazepines has been reported previously. Similarly, MM's perceptual and behavioral disturbances were managed with antipsychotics during her admission. However, addressing the underlying cause by reinstating and slowly tapering off baclofen has also been demonstrated to be an effective, targeted approach.

Intranasal esketamine: From origins to future implications in treatment-resistant depression.

The approval of intranasal esketamine for treatment-resistant depression marks the next step in our understanding of and ability to treat treatment-resistant depression. The origin of ketamine is rooted in the search for a phencyclidine analog that could be used as a pre-surgical anesthetic with less emergence delirium. Following its inception, ketamine has been used in a variety of contexts. However, it was the seminal Berman et al., 2000 study, which published positive findings from the first human trial using subanesthetic intravenous ketamine for depression. Since then, a large body of research has investigated ketamine's various proposed antidepressant mechanisms of action, and the role its pharmacokinetic properties and route of administration play in producing its antidepressant effects. The results of this research were the eventual approval of intranasal esketamine for treatment-resistant depression by the U.S. Food and Drug Administration (FDA) in March 2019. By identifying and utilizing predictors of response, we can continue to refine our approach to treating treatment-resistant depression and optimize patient response to intranasal esketamine. In this article, we look at the history, pharmacology, landmark studies, and future implications of intranasal esketamine for treatment-resistant depression.

Priorities of Hybrid Clinician-Managers: A Qualitative Study of How Managers Balance Clinical Quality Among Competing Responsibilities.

OBJECTIVE: Oversight of clinical quality is only one of physical therapy managers' multiple responsibilities. With the move to value-based care, organizations need sound management to navigate this evolving reimbursement landscape. Previous research has not explored how competing priorities affect physical therapy managers' oversight of clinical quality. The purpose of this study was to create a preliminary model of the competing priorities, motivations, and responsibilities of managers while overseeing clinical quality. METHODS: This qualitative study used the Rapid Qualitative Inquiry method. A purposive sample of 40 physical therapy managers and corporate leaders was recruited. A research team performed semi-structured interviews and observations in outpatient practices. The team used a grounded theory-based immersion/crystallization analysis approach. Identified themes delineated the competing priorities and workflows these managers use in their administrative duties. RESULTS: Six primary themes were identified that illustrate how managers: (1) balance managerial and professional priorities; (2) are susceptible to stakeholder influences; (3) experience internal conflict; (4) struggle to measure and define quality objectively; (5) are influenced by the culture and structure of their respective organizations; and (6) have professional needs apart from the needs of their clinics. CONCLUSION: Generally, managers' focus on clinical quality is notably less comprehensive than their focus on clinical operations. Additionally, the complex role of hybrid clinician-manager leaves limited time beyond direct patient care for administrative duties. Managers in organizations that hold them accountable to quality-based metrics have more systematic clinical quality oversight processes. IMPACT: This study gives physical therapy organizations a framework of factors that can be influenced to better facilitate managers' effective oversight of clinical quality. Organizations offering support for those managerial responsibilities will be well positioned to thrive in the new fee-for-value care structure.

Thin Magnetically Permeable Targets for Inductive Sensing: Application to Limb Prosthetics.

The purpose of this research was to create a thin ferrous polymer composite to be used as a target for inductive sensing in limb prosthetics. Inductive sensors are used to monitor limb-to-socket distance in prosthetic sockets, which reflects socket fit. A styrene-ethylene-ethylene/propylene-styrene (SEEPS) polymer was mixed with iron powder at three concentrations (75, 77, 85 wt%), and thin disk-shaped samples were fabricated (0.50, 0,75, 1.00 mm thickness). For 85 wt% samples of 0.50 mm thickness, which proved the best combination of high signal strength and low target volume, inductive sensor sensitivity ranged from 3.2E5 counts/mm at 0.00-1.00 mm distances to 7.2E4 counts/mm at 4.00-5.00 mm distances. The application of compressive stress (up to 425 kPa) introduced an absolute measurement error of less than 3.3 µm. Tensile elasticity was 282 kPa, which is comparable to that of commercial elastomeric liners. Durability testing in the shoe of an able-bodied participant demonstrated a change in calibration coefficient of less than 3.8% over two weeks of wear. The ferrous polymer composite may facilitate the development of automatically adjusting sockets that use limb-to-socket distance measurement for feedback control.

Emergency department utilization by a jail population.

BACKGROUND: Incarcerated individuals represent a significant proportion of the US population and face unique healthcare challenges. Scarce articles have been published about emergency department (ED) care of these patients. We studied the ED visits from one urban jail to better describe this population. METHODS: A cohort study design was used, identifying patients who were sent to the ED from a city jail in 2015. Demographics, triage information, length of stay, number of studies, billing codes, diagnoses, and disposition data were collected. These were compared to the overall ED patient population in the same year. RESULTS: 868 ED visits by jail patients occurred, representing 1.3% of the ED census. Compared to the general population, incarcerated patients were younger (32.1 years vs. 44.0 years, p < .01), healthier based on Elixhauser comorbidity scores (0.71 vs. 0.98, p < .01), and had lower admission rates (11.29% vs. 21.54%, p < .01). An abnormal vital sign was noted in 25% of incarcerated patients. Laboratory (61% vs. 57%, p < .02) and radiologic (63% vs 45%, p < .001) testing was more frequent for inmates and length of stay was longer (271 vs. 225 min, p < .01). CONCLUSION: ED visits from jail were common, involving a relatively young and healthy population with a low incidence of abnormal vital signs and admission. Given the high costs associated with ED care and the medical resources available at some jails, further study should evaluate if increased jail medical capabilities could improve care and decrease costs by decreasing ED visits.

A New EHR Training Curriculum and Assessment for Pediatric Residents.

Background Conventional classroom Electronic Health Record (EHR) training is often insufficient for new EHR users. Studies suggest that enhanced training with a hands-on approach and closely supported clinical use is beneficial. Objectives Our goals were to develop an enhanced EHR learning curriculum for Post Graduate Year 1 (PGY1) residents and measure changes in EHR skill proficiency, efficiency, and self-efficacy. Methods A novel three-phase, multimodal enhanced EHR curriculum was designed for a cohort of PGY1 residents. After basic training, residents began phase 1 of enhanced training, including demonstrations, live practice, and order set review. Phase 2 involved skills-oriented assignments, role playing, and medication entry. Phase 3 included shadowing, scribing histories, and supervised order entry. Residents' EHR skills and attitudes were measured and compared before and after the enhanced curriculum via proficiency test and a survey of efficiency and self-efficacy. Results Nineteen of 26 PGY1 residents participated in the study (73%). There was significant improvement in mean proficiency scores and two of the five individual proficiency scores. There were significant improvements in most efficiency survey responses from pre- to postintervention. For the self-efficacy presurvey, many PGY1s reported to be "very" or "somewhat confident" performing each of the five tasks, and perceptions did not improve or worsened on most postsurvey responses. The greatest resource was the time required to design and deliver the enhanced training. Conclusion An enhanced training curriculum along with a proficiency assessment was developed and described here. An enhanced training curriculum significantly improved PGY1 EHR efficiency and some measures of proficiency but not self-efficacy. This intervention may support improved EHR-related clinic workflows, which ultimately could enable residents and preceptors to prioritize patient care and time for clinical education.