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Abstract This work addresses the growing need for an intuitive, systematic approach to low-thrust spacecraft formation flying by extending shape-based continuous thrust trajectory design methods to the relative motion of two spacecraft. There is widespread interest in distributed space systems for their low costs, broad capabilities, and high redundancy. This trend introduces a new challenge for trajectory design when combined with the increasing prevalence of low-thrust, high specific impulse electric propulsion systems. That challenge is met herein with a geometrically intuitive, semi-analytical solution to the low-thrust problem. Beginning with the equations of relative motion of two spacecraft, an unperturbed chief and a continuously-thrusting deputy, a thrust profile is constructed which transforms the equations into a form that is solved analytically. The resulting relative trajectories are the family of sinusoidal spirals, which provide diversity for design and optimization based upon a single thrust parameter. Closed-form expressions are derived for the trajectory shape and time-of-flight for two prescribed relative velocity behaviors, and used to develop a novel patched-spirals trajectory design and optimization method. The example problem of a servicer spacecraft establishing and reconfiguring a formation around a target in geostationary earth orbit is used to demonstrate the application of the patched spirals technique as well as the advantages of the relative spiral trajectories over impulsive maneuvers. The sensitivity of the trajectory solutions to deviations from the underlying assumptions, uncertainties in the state, and errors in thrust are studied through high-fidelity simulation. Highlights • Semi-analytical, shape-based approach to spacecraft formation flying derived. • Simple thrust profile leads to sinusoidal spiral trajectories. • Application to formation establishment and reconfiguration for GEO servicer mission. • Open-loop sensitivity to uncertainties in state and thrust quantified. [ABSTRACT FROM AUTHOR]

Purpose: To examine the risk factors for internalizing (anxiety, depression) and posttraumatic stress (PTSD) disorders, somatization, and anxiety sensitivity (AS) in youth with psychogenic non-epileptic seizures (PNES).Methods: 55 probands with PNES and 35 siblings, aged 8-18 years, underwent a psychiatric interview, cognitive and language testing, and completed somatization and AS questionnaires. Parents provided the subjects' medical, psychiatric, family, and adversity history information.Results: The risk factors for the probands' internalizing disorders (girls, older age of PNES onset), somatization (older age, epilepsy), and anxiety sensitivity (girls, adversities) differed from their siblings. The risk factors in the siblings, however, were similar to the general pediatric population. Proband depression was unrelated to the study's risk variables while PTSD was significantly associated with female gender and lower Full Scale IQ.Conclusions: Knowledge about the specificity of the risk factors for comorbid psychopathology in youth with PNES might facilitate their early identification and treatment. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: Youth with chronic illness often struggle transitioning to adulthood and adult medical care. This article examines the outcomes of a group mentoring program called The Adolescent Leadership Council (TALC) that brings together high school participants and college mentors, all with chronic illness. TALC uses a positive youth development (PYD) approach, emphasizing strong relationships between youth and adults in an environment where youth can learn important life skills and take a leadership role. Methods: A pre-/postprogram participant survey was conducted for high school participants using a loneliness scale and a transition readiness survey. An alumni survey was conducted with all high school and college mentor graduates to assess educational-, vocational-, and health care-related outcomes. Results: Program records review and the alumni survey indicated that TALC was consistent with the PYD program model. Twenty high school students participated in the pre-/postprogram outcomes evaluation, which demonstrated a decrease in loneliness from 46 to 38.5 (p < .001) and an increase in health care self-advocacy from 3.8 to 4.2 (p < .001). Thirty-four alumni participated in the alumni survey. All high school and college mentor alumni had graduated from high school and college, respectively, and all were either currently in school or working. The majority of alumni were seeing adult providers for medical care. Conclusions: The TALC program applies the principles of PYD to support positive educational, vocational, and health care outcomes for youth with chronic illness. Program development using the PYD perspective is an important new approach for supporting adult development of youth with chronic illness. [Copyright &y& Elsevier]

Background: This study evaluated the outcomes of patients with failed total shoulder arthroplasty (TSA) who were treated with conversion to reverse shoulder arthroplasty (RSA). Materials and methods: We performed a retrospective case series of 24 consecutive patients with failed TSA who were treated with conversion to RSA. Twenty-two patients (16 women, 6 men) had a minimum 2-year clinical and radiographic follow-up. The average age at the time of revision was 68 years (range, 51-84 years). Indications for conversion to RSA included failure of TSA from glenohumeral instability in 19, mechanical failure of the humeral or glenoid component in 10, and infection in 2. Results: The median total American Shoulder and Elbow Surgeons score improved from 38.5 preoperatively to 67.5 (P < .001). Visual analog scale pain scores decreased from 5 to 1.5 (P < .001), and function improved from 2 to 6.5 (P < .001). The median Simple Shoulder Test improved from 1 to 5 (P = .006). Forward flexion improved from 50° to 130° (P < .001), abduction from 45° to 100° (P < .001), and external rotation from 12.5° to 49.5° (P = .056). Internal rotation improved from a spinal level of S2 to L3 (P = .064). Fourteen patients rated their outcome as excellent, 3 as good, 3 as satisfactory, and 2 as unsatisfactory. The overall complication rate was 22.7% (5 of 22). Conclusion: RSA can be an effective treatment for failed TSA by decreasing pain and improving shoulder function. However, RSA in the revision setting is associated with a higher complication rate. [ABSTRACT FROM AUTHOR]

Background: The purpose of this study was to determine the outcomes of patients with proximal humeral malunions treated with reverse shoulder arthroplasty (RSA). Materials and methods: Sixteen patients were treated with RSA for sequelae of a proximal humeral fracture with a malunion. Clinical outcomes (American Shoulder and Elbow Surgeons [ASES] score, Simple Shoulder Test, visual analog scale [VAS] score for pain and function, range of motion, and patient satisfaction) and radiographs were evaluated at a minimum follow-up of 2 years. Wilcoxon signed-rank tests were used to analyze preoperative and postoperative data. Results: All patients required alteration of humeral preparation with increased retroversion of greater than 30°. The total ASES score improved from 28 to 63 (P = .001), ASES pain score from 15 to 35 (P = .003), ASES functional score from 15 to 27 (P = .015), VAS pain score from 7 to 3 (P = .003), VAS function score from 0 to 5 (P = .001), and Simple Shoulder Test score from 1 to 4 (P = .0015). Forward flexion improved from 53° to 105° (P = .002), abduction from 48° to 105° (P = .002), external rotation from 5° to 30° (P = .015), and internal rotation from S1 to L3 (P = .005). There were no major complications reported. Postoperative radiographic evaluation showed 2 patients with evidence of notching and 1 patient with proximal humeral bone resorption. Conclusion: RSA is indicated for treating the most severe types of proximal humeral fracture sequelae. The results of RSA for proximal humeral malunions with altered surgical technique yield satisfactory outcomes in this difficult patient population. [ABSTRACT FROM AUTHOR]

Hypothesis/background: Reverse shoulder arthroplasty is being used with greater frequency for patients with severe rotator cuff deficiency. There are several commercially available reverse shoulder devices, each with different glenosphere options. The purpose of this study was to determine: (1) forces at the baseplate-bone interface in glenospheres with centers of rotation located concentrically and eccentrically to the center of the baseplate; and (2) if baseplate-bone forces can be optimized by altering tilt of the baseplate. Methods: A validated computer model was used to compare concentric glenospheres with neutral offset to eccentrically offset glenospheres (6 mm inferior or 6 mm lateral) in 3 baseplate tilts: 15° inferior, neutral, or 15° superior. A baseplate, simulated bone, screws, and humeral component were modeled, and forces underneath the baseplate were calculated as the arm was abducted through 90° of glenohumeral motion. Results: For lateral and concentric glenospheres, inferior tilt provides the most even distribution of forces (mean difference in force between superior and inferior portions of baseplate: 11.3 N and 24.7 N, respectively) and superior tilt provides the most uneven distribution of forces (109.3 N and 78.7 N, respectively). For inferior eccentric glenospheres, inferior tilt provides the most uneven distribution of forces (58.7 N) and neutral tilt provides the most even distribution of forces (27.7 N). Conclusion: This is the first study to investigate force distribution under the baseplate in inferior eccentric glenospheres. Although inferior tilting of the baseplate is recommended for concentric and laterally offset glenospheres, this same recommendation may be detrimental to inferiorly offset glenospheres and warrants further investigation. [ABSTRACT FROM AUTHOR]

Abstract: It is often said that bushfires are a fact of life in Australia. While Australian communities will always be affected by the impacts of bushfires, there is an element of human involvement that makes at least some bushfires avoidable. In Australia more bushfires are started by deliberate lighting than are caused by lightning or other natural sources. This creates an element of criminality in relation to bushfires which includes the establishment of bushfire arson as a serious criminal offence. The author presents a motive-based typology of deliberately lit bushfires and argues that a greater understanding of the reasons why people light bushfires can help prevention, investigation and treatment of offenders. [Copyright &y& Elsevier]

The goal of this session is to review articles chosen by AACAP's Lifelong Learning Committee highlighting topics important for child and adolescent psychiatrists in the integrated management of patients with co-occurring medical and mental health issues. Important topics include the following: 1) eating disorders; 2) hormonal contraception; 3) sports-related concussion; 4) delirium in pediatric critical care; 5) autoimmune encephalitis; and 6) PANS. 5) Child psychiatrists must be familiar with the diagnosis and treatment of autoimmune encephalitis, because they may be the initial evaluators of children presenting with symptoms otherwise misconstrued as purely mental and may follow these patients longitudinally outside of the acute phase of illness. [Extracted from the article]

Social media sites like Twitter (now X) are increasingly used to create health behavior metrics for public health surveillance. Yet little is known about social norms that may bias the content of posts about health behaviors. Social norms for posts about four health behaviors (smoking tobacco, drinking alcohol, physical activity, eating food) on Twitter/X were evaluated. This was a randomized experiment delivered via web-based survey to adult, English-speaking Twitter/X users in three Michigan, USA, counties from 2020 to 2022 (n =559). Each participant viewed 24 posts presenting experimental manipulations regarding four health behaviors and answered questions about each post's social acceptability. Principal component analysis was used to combine survey responses into one perceived social acceptability measure. Linear mixed models with the Benjamini–Hochberg correction were implemented to test seven study hypotheses in 2023. Supporting six hypotheses, posts presenting healthier (CI: 0.028, 0.454), less stigmatized behaviors (CI: 0.552, 0.157) were more socially acceptable than posts regarding unhealthier, stigmatized behaviors. Unhealthy (CI: −0.268, −0.109) and stigmatized behavior (CI: −0.261, −0.103) posts were less acceptable for more educated participants. Posts about collocated activities (CI: 0.410, 0.573) and accompanied by expressions of liking (CI: 0.906, 1.11) were more acceptable than activities undertaken alone or disliked. Contrary to one hypothesis, posts reporting unusual activities were less acceptable than usual ones (CI: −0.472, 0.312). Perceived social acceptability may be associated with the frequency and content of health behavior posts. Users of Twitter/X and other social media platform posts to estimate health behavior prevalence should account for potential estimation biases from perceived social acceptability of posts. [ABSTRACT FROM AUTHOR]

An abstract of the article "Partial Hospital Program for Adolescents With Physical Illness" by Matthew Willis is presented.

An abstract of the article "Family-based integrated care in a partial hospital program" by Matthew Willis is presented.

The adult CNS does not spontaneously regenerate after injury, due in large part to myelin-associated inhibitors such as myelin-associated glycoprotein (MAG), Nogo-A, and oligodendrocyte- myelin glycoprotein. All three inhibitors can interact with either the Nogo receptor complex or paired immunoglobulin- like receptor B. A conditioning lesion of the sciatic nerve allows the central processes of dorsal root ganglion (DRG) neurons to spontaneously regenerate in vivo after a dorsal column lesion. After a conditioning lesion, DRG neurons are no longer inhibited by myelin, and this effect is cyclic AMP (cAMP)- and transcription-dependent. Using a microarray analysis, we identified several genes that are up-regulated both in adult DRGs after a conditioning lesion and in DRG neurons treated with cAMP analogues. One gene that was up-regulated under both conditions is metallothionein (MT)-I. We show here that treatment with two closely related isoforms of MT (MT-I/II) can overcome the inhibitory effects of both myelin and MAG for cortical, hippocampal, andDRGneurons. Intrathecal delivery of MT-I/II to adult DRGs also promotes neurite outgrowth in the presence of MAG. Adult DRGs from MT-I/II-deficient mice extend significantly shorter processes on MAG compared with wild-type DRG neurons, and regeneration of dorsal column axons does not occur after a conditioning lesion in MT-I/II-deficient mice. Furthermore, a single intravitreal injection of MT-I/II after optic nerve crush promotes axonal regeneration. Mechanistically, MT-I/II ability to overcome MAG-mediated inhibition is transcription-dependent, and MT-I/II can block the proteolytic activity of &#945-secretase and the activation of PKC and Rho in response to soluble MAG. [ABSTRACT FROM AUTHOR]