557 research outputs found
Sampled Policy Gradient for Learning to Play the Game Agar.io
In this paper, a new offline actor-critic learning algorithm is introduced:
Sampled Policy Gradient (SPG). SPG samples in the action space to calculate an
approximated policy gradient by using the critic to evaluate the samples. This
sampling allows SPG to search the action-Q-value space more globally than
deterministic policy gradient (DPG), enabling it to theoretically avoid more
local optima. SPG is compared to Q-learning and the actor-critic algorithms
CACLA and DPG in a pellet collection task and a self play environment in the
game Agar.io. The online game Agar.io has become massively popular on the
internet due to intuitive game design and the ability to instantly compete
against players around the world. From the point of view of artificial
intelligence this game is also very intriguing: The game has a continuous input
and action space and allows to have diverse agents with complex strategies
compete against each other. The experimental results show that Q-Learning and
CACLA outperform a pre-programmed greedy bot in the pellet collection task, but
all algorithms fail to outperform this bot in a fighting scenario. The SPG
algorithm is analyzed to have great extendability through offline exploration
and it matches DPG in performance even in its basic form without extensive
sampling
The normalization of sibling violence: Does gender and personal experience of violence influence perceptions of physical assault against siblings?
Despite its pervasive and detrimental nature, sibling violence (SV) remains marginalized as a harmless and inconsequential form of familial aggression. The present study investigates the extent to which perceptions of SV differ from those of other types of interpersonal violence. A total of 605 respondents (197 males, 408 females) read one of four hypothetical physical assault scenarios that varied according to perpetrator–victim relationship type (i.e., sibling vs. dating partner vs. peer vs. stranger) before completing a series of 24 attribution items. Respondents also reported on their own experiences of interpersonal violence during childhood. Exploratory factor analysis reduced 23 attribution items to three internally reliable factors reflecting perceived assault severity, victim culpability, and victim resistance ratings. A 4 × 2 MANCOVA—controlling for respondent age—revealed several significant effects. Overall, males deemed the assault less severe and the victim more culpable than did females. In addition, the sibling assault was deemed less severe compared to assault on either a dating partner or a stranger, with the victim of SV rated just as culpable as the victim of dating, peer, or stranger-perpetrated violence. Finally, respondents with more (frequent) experiences of childhood SV victimization perceived the hypothetical SV assault as being less severe, and victim more culpable, than respondents with no SV victimization. Results are discussed in the context of SV normalization. Methodological limitations and applications for current findings are also outlined
Surfaces with prescribed Weingarten-Operator
We investigate pairs of surfaces in Euclidean 3-space with the same Weingarten operator in case that one surface is given as surface of revolution. Our local and global results complement global results on ovaloids of revolution from [S-V-W-W]
Creation of a Decision Support Tool for Expectant Parents Facing Threatened Periviable Delivery: Application of a User-Centered Design Approach
Background
Shared decision-making (SDM) is optimal in the context of periviable delivery, where the decision to pursue life-support measures or palliation is both preference sensitive and value laden. We sought to develop a decision support tool (DST) prototype to facilitate SDM by utilizing a user-centered design research approach.
Methods
We convened four patient and provider advisory boards with women and their partners who had experienced a surviving or non-surviving periviable delivery, pregnant women who had not experienced a prior preterm birth, and obstetric providers. Each 2-h session involved design research activities to generate ideas and facilitate sharing of values, goals, and attitudes. Participant feedback shaped the design of three prototypes (a tablet application, family story videos, and a virtual reality experience) to be tested in a final session.
Results
Ninety-five individuals (48 mothers/partners; 47 providers) from two hospitals participated. Most participants agreed that the prototypes should include factual, unbiased outcomes and probabilities. Mothers and support partners also desired comprehensive explanations of delivery and care options, while providers wanted a tool to ease communication, help elicit values, and share patient experiences. Participants ultimately favored the tablet application and suggested that it include family testimonial videos.
Conclusion
Our results suggest that a DST that combines unbiased information and understandable outcomes with family testimonials would be meaningful for periviable SDM. User-centered design was found to be a useful method for creating a DST prototype that may lead to improved effectiveness, usability, uptake, and dissemination in the future, by leveraging the expertise of a wide range of stakeholders
A toolset of functionalized porphyrins with different linker strategies for application in bioconjugation
The reaction of amines with pentafluorophenyl-substituted A3B-porphyrins has
been used to obtain different useful reactive groups for further
functionalization and/or conjugation of these porphyrins to other substrates
or materials. Porphyrins with alkenyl, alkynyl, amino, azido, epoxide,
hydroxyl, and maleimido groups have thus been synthesized. For the first time
such functionalized porphyrins have been conjugated to hyperbranched
polyglycerol (hPG) as a biocompatible carrier system for photodynamic therapy
(PDT) using the copper(I)-catalyzed 1,3-dipolar cycloaddition (CuAAC). The
photocytotoxicity of selected porphyrins as well as of the porphyrin-hPG-
conjugates has been assessed in cellular assays with human epidermoid
carcinoma A-253 and squamous carcinoma CAL-27 cells. For several biomedical
applications a release of the active drug and/or fluorescent dye is desired.
Therefore, additionally, the synthesis of A3B-porphyrins with cleavable linker
moieties is presented, namely disulfide, cleavable in a reductive environment,
and acetal linkers whose cleavage is pH triggered
Codesigned Shared Decision-Making Diabetes Management Plan Tool for Adolescents With Type 1 Diabetes Mellitus and Their Parents: Prototype Development and Pilot Test
Background: Adolescents with type 1 diabetes mellitus have difficulty achieving optimal glycemic control, partly due to competing priorities that interfere with diabetes self-care. Often, significant diabetes-related family conflict occurs, and adolescents’ thoughts and feelings about diabetes management may be disregarded. Patient-centered diabetes outcomes may be better when adolescents feel engaged in the decision-making process.
Objective: The objective of our study was to codesign a clinic intervention using shared decision making for addressing diabetes self-care with an adolescent patient and parent advisory board.
Methods: The patient and parent advisory board consisted of 6 adolescents (teens) between the ages 12 and 18 years with type 1 diabetes mellitus and their parents recruited through our institution’s Pediatric Diabetes Program. Teens and parents provided informed consent and participated in 1 or both of 2 patient and parent advisory board sessions, lasting 3 to 4 hours each. Session 1 topics were (1) patient-centered outcomes related to quality of life, parent-teen shared diabetes management, and shared family experiences; and (2) implementation and acceptability of a patient-centered diabetes care plan intervention where shared decision making was used. We analyzed audio recordings, notes, and other materials to identify and extract ideas relevant to the development of a patient-centered diabetes management plan. These data were visually coded into similar themes. We used the information to develop a prototype for a diabetes management plan tool that we pilot tested during session 2.
Results: Session 1 identified 6 principal patient-centered quality-of-life measurement domains: stress, fear and worry, mealtime struggles, assumptions and judgments, feeling abnormal, and conflict. We determined 2 objectives to be principally important for a diabetes management plan intervention: (1) focusing the intervention on diabetes distress and conflict resolution strategies, and (2) working toward a verbalized common goal. In session 2, we created the diabetes management plan tool according to these findings and will use it in a clinical trial with the aim of assisting with patient-centered goal setting.
Conclusions: Patients with type 1 diabetes mellitus can be effectively engaged and involved in patient-centered research design. Teens with type 1 diabetes mellitus prioritize reducing family conflict and fitting into their social milieu over health outcomes at this time in their lives. It is important to acknowledge this when designing interventions to improve health outcomes in teens with type 1 diabetes mellitus
A PRELIMINARY STUDY OF THE EFFECT OF SURFACE COATING ON THE INITIAL DEPOSITION MECHANISMS OF DAIRY FOULING
Adolescent Burmese Refugees Perspectives on Determinants of Health
Over 70,000 Burmese refugees have resettled in the United States in the past decade. While Burmese adolescents quickly acculturate into American society, their perspectives on health are not well-known. The purpose of this study was to identify adolescent Burmese refugee perspectives on determinants of health and health-related experiences after resettlement. In this qualitative study, Burmese adolescents took photographs depicting health-related experiences that were used as elicitation tools during focus groups. These discussions were recorded, transcribed, and analyzed for themes. Participants described positive determinants of health, including family and church. Rampant tobacco use was identified by the participants as a determinant of poor health within the Burmese community. Notably, the participants were proud to serve as liaisons within their community, despite the stressful nature of this role. Our results highlight the need to screen this population for anxiety, secondary to serving as a liaison for their community, as well as tobacco use
‘I Got it off my Chest’: An Examination of how Research Participation Improved the Mental Health of Women Engaging in Transactional Sex
Ecologic momentary assessment (EMA) is a form of close-ended diary writing. While it has been shown that participating in a study that incorporates EMA improves mental health of participants, no study to date has examined the pathways through which benefits may occur. For 4-weeks, twice-daily EMAs and weekly interviews captured mood, daily activities and HIV risk behavior of 25 women who engage in transactional sex. Qualitative analysis of exit interviews was performed to examine how participation impacted women's mental health. The majority of participants felt that EMAs heightened awareness of emotions and behavior. Most reported experiencing catharsis from the interviews; specifically, from having a non-judgmental, trusting listener. Participants felt responsible for completing tasks, a sense of accomplishment for completing the study, and altruism. This study demonstrates there are direct benefits associated with participation in an EMA and interview study
Characterisation of irradiated and non-irradiated silicon sensors with a table-top two photon absorption TCT system
A tabletop Two Photon Absorption-Transient Current Technique (TPA-TCT) set-up built at CERN was used to investigate a non-irradiated PIN diode, an irradiated PIN diode, and a non-irradiated 5 × 5-multipad HPK LGAD. The intrinsic three dimensional spatial resolution of this method is demonstrated under normal incidence of the laser probe. A charge collection versus depth profile of the non-irradiated PIN diode is presented, where reflection on the rear silicon-air interface was observed. It is found that the time-over-threshold versus depth profile is particularly suitable to determine the boundaries of the DUT's active volume. A depth scan of the irradiated PIN diode is discussed and a method to omit the single photon absorption background is presented. Finally, a charge collection measurement in the inter-pad region of the 5 × 5-multipad HPK LGAD is presented and it is demonstrated that TPA-TCT can be used to image the implantation and the electric field of segmented silicon devices in a three dimensional manner
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