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OBJECTIVE In this study, we tested direct pathways from trauma exposure to trauma symptomatology and risky and self-destructive behavior and indirect pathways through two cognitive and affective mechanisms: (a) world assumptions and (b) emotion dysregulation. METHOD A sample of 270 undergraduate students with an average age of 20.02 years participated in the study (204 women, 65 men, and one participant choosing not to disclose). Participants completed self-report measures assessing trauma exposure, trauma symptoms, emotion dysregulation, world assumptions, and lifetime and past-month engagement in any of 38 risky and self-destructive behaviors. RESULTS The direct path from trauma exposure to trauma symptoms was significant, and so was the indirect effect of self-worth assumptions on this association. The indirect pathway between trauma symptoms and risky and self-destructive behavior in the past month was significant through difficulties with impulse control when distressed. Trauma symptoms had an indirect effect on the association between trauma exposure and lifetime and past-month engagement in risky and self-destructive behavior, while the direct pathway from trauma exposure to lifetime engagement remained significant. CONCLUSION We offer theoretically and empirically supported integrative pathways that explicate some aspects of trauma exposure's negative sequelae with potential areas for intervention. Clinical Impact Statement: Trauma exposure is widespread and is associated with negative views about oneself and the world and with difficulties in managing one's emotions, which in part is associated with individuals' risk for developing psychopathology and engaging in risky and self-destructive behaviors. The findings inform optimal time for intervention and prevention efforts targeting trauma exposure. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

A hydraulic drive-based self-propelled photovoltaic panel cleaning robot was developed to tackle the challenges of harsh environmental conditions, difficult roads, and incomplete cleaning of dust particles on the photovoltaic panel surface in photovoltaic power plants. The robot has the characteristics of the crawler wheel drive, rear-wheel-independent turning and three-point-independent suspension design, which makes it adhere to the walking requirements of complex environmental terrains, more flexible in turning and automatically levelling so that the stability of the boom mechanism during walking can be ensured. The kinematics model of the upper arm structure equipped with the end cleaning device was built, and the optimized Circle chaotic map and nonlinear weight factor were introduced to enhance the search ability and convergence speed of the sparrow algorithm. Furthermore, the boom running track was optimized in combination with the seven-order non-uniform B-spline curve. Through optimization, the running time of the boom was reduced by 18.7%, and the cleaning efficiency of photovoltaic panel surface was increased. The effectiveness of self-propelled photovoltaic panel cleaning robot cleaning and the reliability of time-optimal trajectory planning were confirmed through simulation and experiment.

Maintenance of miter gates in navigation locks is crucial to facilitate water navigation of cargo ships. Scheduled and unscheduled maintenance are the two types of actions performed to keep miter gates continuously operational. In practice, visual inspections and rating systems are used to monitor the current state of miter gate components in order to prioritize maintenance. This paper shows an example of how to find the optimal time to plan for maintenance using deterioration curves obtained from real visual inspection assessments of components in miter gates. Predictive deterioration curves are derived using a Markov Chain approach. In addition, the advantages of implementing Structural Health Monitoring (SHM) are discussed.

In this paper, a computationally efficient time-optimal feedback solution to the game of two cars, for the case where the pursuer is faster and more agile than the evader, is presented. The concept of continuous subsets of the reachable set is introduced to characterize the time-optimal pursuit-evasion game under feedback strategies. Using these subsets it is shown that, if initially the pursuer is distant enough from the evader, then the feedback saddle point strategies for both the pursuer and the evader are coincident with one of the common tangents from the minimum radius turning circles of the pursuer to the minimum radius turning circles of the evader. Using geometry, four feasible tangents are identified and the feedback min-max strategy for the pursuer and the max-min strategy for the evader are derived by solving a 2 2 matrix game at each instant. Insignificant computational effort is involved in evaluating the pursuer and evader inputs using the proposed feedback control law and hence it is suitable for real-time implementation.

We consider a susceptible, infected, and recovered infectious disease model which incorporates a vaccination rate. In particular, we study the problem of choosing the vaccination rate in order to reduce the number of infected individuals to a given threshold as quickly as possible. This is naturally a problem of time-optimal control. We interpret the optimal time as a solution of two dynamic programming equations and give necessary and sufficient conditions for a vaccination rate to be optimal.

We propose a self-stabilizing leader election protocol on directed rings in the model of population protocols. Given an upper bound $N$ on the population size $n$, the proposed protocol elects a unique leader within $O(nN)$ expected steps starting from any configuration and uses $O(N)$ states. This convergence time is optimal if a given upper bound $N$ is asymptotically tight, i.e., $N=O(n)$.

This article investigates the optimal investment-reinsurance problem for state-dependent risk aversion with delay and common shock dependence. We suppose that the insurer manages insurance risk whi...

We establish a highly feasible algorithm for time-optimal cornering trajectory planning (TP) for car-like mobile robots (CLMRs) based on a dynamic model that contains actuator dynamics. First, we formulate an accurate dynamic model of a robot that contains DC motor actuators; this includes steering braking (caused by the lateral force of the front steering wheel) and two types of friction (viscous and Coulomb) under a nonslip condition. Our TP algorithm can utilize the full power of the DC motor actuators within proper pulse width modulation bounds and generated torque limits. Then, we establish an algorithm for a time-optimal cornering trajectory planning for CLMRs (TOCTP-CLMR). Our algorithm divides the trajectory into five sections comprising three turnings and two translations to minimize the travel distance. Then, we utilize the quickest rotation when turning to construct the time-optimal trajectory that satisfies the bang-bang principle. In addition, simulations are performed to demonstrate the validity of this method. Finally, we conduct open-loop experiments to validate our dynamic model and a trajectory tracking experiment to demonstrate the feasibility of the TOCTP-CLMR trajectory.

Sodium-glucose cotransporter-2 inhibitor therapy is well suited for initiation during the heart failure hospitalization, owing to clinical benefits that accrue rapidly within days to weeks, a strong safety and tolerability profile, minimal to no effects on blood pressure, and no excess risk of adverse kidney events. There is no evidence to suggest that deferring initiation to the outpatient setting accomplishes anything beneficial. Instead, there is compelling evidence that deferring in-hospital initiation exposes patients to excess risk of early postdischarge clinical worsening and death. Lessons from other heart failure with reduced ejection fraction therapies highlight that deferring initiation of guideline-recommended medications to the U.S. outpatient setting carries a >75% chance they will not be initiated within the next year. Recognizing that 1 in 4 patients hospitalized for worsening heart failure die or are readmitted within 30 days, clinicians should embrace the in-hospital period as an optimal time to initiate sodium-glucose cotransporter-2 inhibitor therapy and treat this population with the urgency it deserves.

Background To explore the effect of the optimal time interval from preoperative transarterial embolization to surgery of carotid body tumors by analyzing surgery-related indicators. Methods This single-center retrospective review included 103 patients and 108 carotid body tumor resections performed between June 2010 and June 2020. All carotid body tumors were divided into three groups based on interval time between transarterial embolization and surgery: 1-day group (G1), 2-day group (G2), and 3-day group (G3). Demographics, inflammatory biomarkers, periprocedural details, and postoperative outcomes were analyzed. Results Among 103 patients, 48.54% were women, and the mean age was 37.07 years. The tumor sizes were 43.83, 44.31, and 42.84 mm in G1, G2, and G3, respectively, and the blood loss and operative time were 163.68, 331.54, and 683.68 mL, and 182.32, 216.31, and 280.79 mins with the prolonged time interval, respectively. Compared with pretransarterial embolization, the expression of white blood cells (109/L) and neutrophils (109/L) were obviously increased post-transarterial embolization in the three groups (G1: white blood cells 6.81 vs 9.32; neutrophils 0.54 vs 0.74, all P Conclusion The optimal time interval between preoperative transarterial embolization and surgical resection resulted as 1 day as patients in this group showed obvious lower blood loss and shorter duration of operation than patients in other groups. Both inflammation and recanalization provided support for these results at some extent.

The effectiveness of social media marketing is a topic of great interest for researchers as well as marketers. To enrich the literature regarding the effectiveness of various types of posts with a web-link, we designed and conducted an experiment on Facebook (FB). This experiment was conducted in a real business environment, through the FB fanpage of a Polish e-commerce store. The observations were analyzed using multiple linear regression and metrics adapted to this experiment from the literature. The results show that a web-link placed in the comments of an FB post, instead of the caption, is more lucrative. It is also shown that, based on the aims of the campaign, such metrics can give valuable information about the optimal time for posting, as well as the interval between posts.

SUMMARY Geriatric hip fractures are complicated by increased morbidity and mortality, and their incidence continues to rise around the world. Frequent considerations in treating geriatric hip fractures include optimal time to surgery, need for preoperative cardiac clearance, risks of operating through anticoagulation, utilization of regional anesthesia, and collaborative care between treatment teams. This article aims to summarize these factors as well as to provide some tips and tricks that can be helpful in their surgical management.

A class of time-optimal control problems in terms of speed in three-dimensional space with a spherical velocity vector is considered. A smooth regular curve $\Gamma$ was chosen as the target set. Pseudo-vertices — characteristic points on $\Gamma,$ responsible for the appearance of a singularity in the optimal result function, are selected. The characteristic features of the structure of a singular set belonging to the family of bisectors are revealed. An analytical representation is found for the extreme points of the bisector corresponding to a fixed pseudo-vertex. As an illustration of the effectiveness of the developed methods for solving nonsmooth dynamic problems, an example of the numerical-analytical construction of resolving structures of a control problem in terms of speed is given.

Beato, M, De Keijzer, KL, Leskauskas, Z, Allen, WJ, Dello Iacono, A, and McErlain-Naylor, SA. Effect of postactivation potentiation after medium vs. high inertia eccentric overload exercise on standing long jump, countermovement jump, and change of direction performance. J Strength Cond Res 35(9): 2616-2621, 2021-This study aimed to evaluate the postactivation potentiation (PAP) effects of an eccentric overload (EOL) exercise on vertical and horizontal jumps and change of direction (COD) performance. Twelve healthy physically active male subjects were involved in a crossover study. The subjects performed 3 sets of 6 repetitions of EOL half squats for maximal power using a flywheel ergometer. Postactivation potentiation using an EOL exercise was compared between a medium (M-EOL) vs. high inertia (H-EOL) experimental condition. Long jump (LJ) was recorded at 30 seconds, 3, and 6 minutes after both EOL exercises and compared with baseline values (control). The same procedure was used to assess countermovement jump (CMJ) height and peak power and 5-m COD test (COD-5m). A fully Bayesian statistical approach to provide probabilistic statements was used in this study. Long jump performance reported improvements after M-EOL and H-EOL exercise (Bayes factor [BF10] = 32.7, strong; BF10 = 9.2, moderate), respectively. Countermovement jump height (BF10 = 135.6, extreme; BF10200, extreme), CMJ peak power (BF10200, extreme; BF10 = 56.1, very strong), and COD-5m (BF10 = 55.7, very strong; BF10 = 16.4, strong) reported improvements after M-EOL and H-EOL exercise, respectively. Between analysis did not report meaningful differences in performance between M-EOL and H-EOL exercises. The present outcomes highlight that PAP using an EOL (M-EOL and H-EOL) improves LJ, CMJ height, CMJ peak power, and COD-5m in male athletes. The optimal time window for the PAP effect was found for both EOL conditions from 3 to 6 minutes. However, M-EOL and H-EOL produce similar PAP effect on LJ, CMJ, and COD-5m tasks.

Background State-of-the-art behavioral weight loss treatment (SBT) can lead to clinically meaningful weight loss, but only 30–60% achieve this goal. Developing adaptive interventions that change based on individual progress could increase the number of people who benefit. Purpose Conduct a Sequential Multiple Assignment Randomized Trial (SMART) to determine the optimal time to identify SBT suboptimal responders and whether it is better to switch to portion-controlled meals (PCM) or acceptance-based treatment (ABT). Method The BestFIT trial enrolled 468 adults with obesity who started SBT and were randomized to treatment response assessment at Session 3 (Early TRA) or 7 (Late TRA). Suboptimal responders were re-randomized to PCM or ABT. Responders continued SBT. Primary outcomes were weight change at 6 and 18 months. Results PCM participants lost more weight at 6 months (−18.4 lbs, 95% CI −20.5, −16.2) than ABT participants (−15.7 lbs, 95% CI: −18.0, −13.4), but this difference was not statistically significant (−2.7 lbs, 95% CI: −5.8, 0.5, p = .09). PCM and ABT participant 18 month weight loss did not differ. Early and Late TRA participants had similar weight losses (p = .96), however, Early TRA PCM participants lost more weight than Late TRA PCM participants (p = .03). Conclusions Results suggest adaptive intervention sequences that warrant further research (e.g., identify suboptimal responders at Session 3, use PCMs as second-stage treatment). Utilizing the SMART methodology to develop an adaptive weight loss intervention that would outperform gold standard SBT in a randomized controlled trial is an important next step, but may require additional optimization work. Clinical Trial information ClinicalTrials.gov identifier; NCT02368002

We prove the controllability and the existence of the time optimal control for semilinear parabolic equations with the homogenous Neumann boundary condition via multiplicative controls. It is worth pointing out that there is no restriction on the growth of the nonlinearity f(s) with respect to the variable s in the equation, which is a remarkable difference compared to the semilinear parabolic system with additive locally distributed controls.

The present work is devoted to a time-optimal control problem for a singularly perturbed linear autonomous system with smooth geometric constraints on the control and an unbounded target set: $$\left\{\begin{array}[]{ll}\phantom{\varepsilon}\dot{x}=A_{11}x+A_{12}y+B_{1}u, &x\in\mathbb{R}^{n},\,y\in\mathbb{R}^{m},\,u\in\mathbb{R}^{r},\\ \varepsilon\dot{y}=A_{21}x+A_{22}y+B_{2}u,&\|u\|\leq 1,\\ x(0)=x_{0}\not=0,\quad y(0)=y_{0},&0

In this paper, we are concerned with the large-time behavior of solutions to the Cauchy problem on the compressible Navier–Stokes equations for ideal reacting gases. The asymptotic stability of the constant equilibrium state with strictly positive constant density, temperature and the vanishing velocity, mass fraction of the reactant is established under suitable small initial perturbation in H N ( R 3 ) ( N ⩾ 3 ) . Precisely, we show the convergence of the density, velocity and temperature towards the corresponding equilibrium state with the optimal rate ( 1 + t ) − 3 4 in L 2-norm as well as the convergence of the mass fraction to the equilibrium state with the optimal rate e − ϕ ( 1 ) t ( 1 + t ) − 3 4 in L 2-norm. Furthermore, the optimal decay rates for the spatial-derivatives of the solution are also obtained. The proof is based on the time-weighted energy estimate and continuation argument.

Objectives To evaluate the optimal timing of tracheostomy for injured adolescents. Design Retrospective cohort study. Setting Trauma facilities in the United States. Patients Adolescents (age 12-17 yr) in the National Trauma Data Bank (2007-2016) who were ventilated for greater than 24 hours and survived to discharge. Interventions None. Measurements and main results After stratifying by traumatic brain injury diagnosis, we compared ICU and hospital length of stay, pneumonia, and discharge disposition of patients with tracheostomy prior to three cut points (3, 7, and 14 d after admission) to 1) patients intubated at least as long as each cut point and 2) patients with tracheostomy on or after each cut point. Of 11,045 patients, 1,391 (12.6%) underwent tracheostomy. Median time to tracheostomy was 9 days (interquartile range, 6-13 d) for traumatic brain injury and 7 days (interquartile range, 3-12 d) for nontraumatic brain injury patients. Nontraumatic brain injury patients with tracheostomy prior to 7 days had 5.6 fewer ICU days (-7.8 to -3.5 d) and 5.7 fewer hospital days (-8.8 to -2.7 d) than patients intubated greater than or equal to 7 days and had 14.8 fewer ICU days (-19.6 to -10.0 d) and 15.3 fewer hospital days (-21.7 to -8.9 d) than patients with tracheostomy greater than or equal to 7 days. Similar differences were observed at 14 days but not at 3 days for both traumatic brain injury and nontraumatic brain injury patients. At the 3- and 7-day cut points, both traumatic brain injury and nontraumatic brain injury patients with tracheostomy prior to the cut point had lower risk of pneumonia and risk of discharge to a facility than those with tracheostomy after the cut point. Conclusions For injured adolescents, tracheostomy less than 7 days after admission was associated with improved in-hospital outcomes compared with those who remained intubated greater than or equal to 7 days and with those with tracheostomy greater than or equal to 7 days. Tracheostomy between 3 and 7 days may be the optimal time point when prolonged need for mechanical ventilation is anticipated; however, unmeasured consequences of tracheostomy such as long-term complications and care needs must also be considered.

Метою цієї роботи є побудова математичної моделі трубного зварного з'єднання, що враховує вплив взаємодії окремих частинок в обсязі матеріалу, з метою визначення залишкових напружень в зразку, до якого застосовано вібраційний вплив в процесі зварювання, а також оптимального часу вібраційного впливу при зварюванні трубної заготовки. Сутність запропонованого способу вібраційної обробки стосовно до зварювання полягає в повідомленні трубній заготовці, що оброблюється вібраційних хвиль в процесі зварювання, запобігаючи таким чином формування залишкових напружень у зварному шві і біляшовній зоні. Виникаючі при зварюванні напруги і деформації в достатній мірі вивчені; на дану тему існує безліч робіт дослідників, в яких були розкриті причини виникнення, класифікації зварювальних напруг і деформацій, методи їх визначення та способи запобігання. З метою запобігання формуванню залишкових напружень в зварному шві і біляшовній зоні запропоновано використання вібраційної обробки трубної заготовки в процесі зварювання. Побудовано математичну модель вібраційної обробки зварного шва і формула для знаходження часу вібраційної обробки, що враховує вплив взаємодії окремих частинок в обсязі матеріалу. Визначення залишкових напружень при вібраційній обробці зварних з'єднань труб було зведено до вирішення задачі математичного програмування. Представлені формули дозволяють отримати аналітичні значення залишкових напружень маючи дані про власну частоту вібрації, коефіцієнт затухання коливань, амплітуду і частоту вимушуючої сили вібрації.

In the quaternion formulation, we consider the problem of the time-optimal rotation of a spacecraft (SC) as a rigid body of an arbitrary dynamic configuration under arbitrary specified boundary conditions. In the class of generalized conical motions, the optimal rotation problem is modified, which makes it possible to obtain its analytical solution. The analytical solution to the modified problem can be considered as an approximate (quasi-optimal) solution to the traditional time-optimal rotation problem. An algorithm for the quasi-optimal rotation of an SC is given. Numerical examples are given showing that the solution of the modified problem closely approximates the solution of the traditional problem of the time-optimal rotation of an SC.

The problem of active suppression of vibrations of an elastic panel moving longitudinally in an ideal fluid flow is considered. The dynamics equation of the panel includes the fluid response and external mechanical action that serves to implement the damping process. The conditions of extremality of lateral vibration damping are derived and the efficiency of the optimal distribution of the forces applied to the panel and the optimal time program of the external influence functioning are estimated.

Integrating backscatter communication (BackCom) into wireless powered communication networks (WPCNs) makes it possible to transmit information and harvest energy simultaneously, which is regarded as a promising method to enhance the throughput. A very important issue is how to allocate the charging time and transmitting time to efficiently utilize the energy in hybrid access point (HAP) so as to improve the network performance. This paper adopts convex optimization to handle the time allocation for both WPCNs and BackCom users. A two‐stage efficient algorithm is proposed to solve the problem of sum‐throughput maximization (STM) subject to the basic throughput requirements of BackCom users, where the Lagrange duality method is applied at the first‐stage, while golden section and bisection method are jointly used at the second‐stage. In order to solve the throughput unfairness among nodes in the STM problem, the common‐throughput maximization (CTM; i.e. the worst node's throughput) problem is further considered. This problem is decomposed into a master problem and a sub‐problem, which are solved in a progressive manner. Simulation results show that the proposed methods obtain substantial improvement compared to the benchmark scheme.

Given the controversies in the prognostic value of KIT mutations and optimal thresholds and time points of MRD monitoring for AML with CBFB-MYH11, we retrospectively evaluated 88 patients who underwent allogeneic hematopoietic stem cell transplantation (Allo-HSCT, n = 60) or autologous HSCT (Auto-HSCT, n = 28). The D816V KIT mutation was significantly associated with post-transplant relapse, contrasting with other types of mutations in KIT. Pre- and post-transplant (3 months after transplant) CBFB-MYH11 MRD assessments were useful in predicting post-transplant relapse and poor survival. The optimal threshold was determined as a 2 log reduction at both time points. In multivariate analysis, the D816V KIT mutation and CBFB-MYH11 MRD assessments were independently associated with post-transplant relapse and survival. Stratification by D816V KIT and pre-transplant CBFB-MYH11 MRD status further distinguished the risk of relapse and survival. Auto-HSCT was superior to Allo-HSCT in MRD negative patients without D816V KIT, while Allo-HSCT trended to be superior to Auto-HSCT in patients with MRD positivity or the D816V KIT mutation. In conclusion, this study demonstrated the differentiated prognostic value of the D816V KIT mutation in AML with CBFB-MYH11 and clarified optimal time points and thresholds for CBFB-MYH11 MRD monitoring in the setting of HSCT.