69 research outputs found
The Limiting Speed of the Bacterial Flagellar Motor
Recent experiments on the bacterial flagellar motor have shown that the
structure of this nanomachine, which drives locomotion in a wide range of
bacterial species, is more dynamic than previously believed. Specifically, the
number of active torque-generating units (stators) was shown to vary across
applied loads. This finding invalidates the experimental evidence reporting
that limiting (zero-torque) speed is independent of the number of active
stators. Here, we propose that, contrary to previous assumptions, the maximum
speed of the motor is not universal, but rather increases as additional
torque-generators are recruited. This result arises from our assumption that
stators disengage from the motor for a significant portion of their
mechanochemical cycles at low loads. We show that this assumption is consistent
with current experimental evidence and consolidate our predictions with
arguments that a processive motor must have a high duty ratio at high loads.Comment: 8 pages, 3 figures (main text); 7 pages, 3 figures (supplementary
Children's evaluation of everyday social encounters questionnaire -- short form validation
The main goal of the current study was to validate a short form of the Children's Evaluation of Everyday Social Encounters Questionnaire (ChEESE-Q). In order to do this, we administered a two-vignette version of the ChEESE-Q (i.e., ChEESE-Q SF) to an independent sample of grade-school children (N=241), along with measures of various adjustment indicators, affect, and emotion regulation. Results indicated that the ChEESE-Q SF fit the same 3-factor structure as the original ChEESE-Q, with each factor-based subscale being invariant across grade and gender. Results also indicated that the ChEESE-Q could not only be shortened at the vignette level, but it could be shortened at the item level as well, and maintain excellent model fit with the same three factor structure. The ChEESE-Q SF also demonstrated acceptable internal consistency and test-retest reliability. In terms of validity, the ChEESE-Q SF subscales correlated with related constructs in expected directions. Specifically, negative information processing was associated with higher anxious and depressive symptomology, as well as higher negative affect. Positive information processing was associated with lower depressive symptomology, and higher positive affect. This study also demonstrated that negative information processing is associated with more aggressive and delinquent behavior and with maladaptive emotion regulation (i.e., inhibition and dysregulation strategies). Positive information processing is associated with more adaptive emotion regulation (i.e., coping strategies. Implications for future research and interventions utilizing the ChEESE-Q SF are discussed.Includes bibliographical reference
Mechanics of torque generation in the bacterial flagellar motor
The bacterial flagellar motor (BFM) is responsible for driving bacterial
locomotion and chemotaxis, fundamental processes in pathogenesis and biofilm
formation. In the BFM, torque is generated at the interface between
transmembrane proteins (stators) and a rotor. It is well-established that the
passage of ions down a transmembrane gradient through the stator complex
provides the energy needed for torque generation. However, the physics involved
in this energy conversion remain poorly understood. Here we propose a
mechanically specific model for torque generation in the BFM. In particular, we
identify two fundamental forces involved in torque generation: electrostatic
and steric. We propose that electrostatic forces serve to position the stator,
while steric forces comprise the actual 'power stroke'. Specifically, we
predict that ion-induced conformational changes about a proline 'hinge' residue
in an -helix of the stator are directly responsible for generating the
power stroke. Our model predictions fit well with recent experiments on a
single-stator motor. Furthermore, we propose several experiments to elucidate
the torque-speed relationship in motors where the number of stators may not be
constant. The proposed model provides a mechanical explanation for several
fundamental features of the flagellar motor, including: torque-speed and
speed-ion motive force relationships, backstepping, variation in step sizes,
and the puzzle of swarming experiments
Project B.L.A.C.K. Barriers Lifted After Cultivating Knowledge: Assessing Individualized Barriers To Obesity Prevention In Black Women Using The Teach-Back Method
Background: Black women are diagnosed, disabled, and die from obesity and associated chronic diseases at higher rates than any other race or sex. Further exploration is warranted on how advanced practice registered nurses (APRN) can improve culturally relevant health education and counseling delivery.
Objective: Explore individualized barriers and the healthcare provider’s roles in providing care affecting obesity prevention among Black women. While simultaneously assessing the effectiveness of educating Black women using the Teach-back method to understand health habits and attitudes.
Method: A mixed-method design was utilized in group sessions and surveys. Participants identifying with obesity and associated diseases were recruited from a predominantly Black church in Atlanta. After completing a demographic survey and pre-Readiness to Change (RCQ) questionnaire, they engaged in weekly, one-hour educational sessions via Zoom addressing the four common barriers identified in the literature. They ended with a 5-10 minute teach-back session. Participants completed a post-RCQ questionnaire after the 4-weeks.
Results: Twenty women completed the intervention. Descriptive statistics and qualitative data from surveys, audio, and emails were used for analysis. Paired sample t-test revealed no statistical significance and showed no correlation between pre and post-test RCQ scores after tailored health education was provided using teach-back. However, correlational analysis between BMI, education, and income level was significant with a p-value of 0.05.
Discussion: Black women depend on healthcare providers for counseling and solutions. Furthermore, they require different approaches in screening, health promotion, and interventions that consistently assess individual risks, tailored education, and the use of Teach-back. Results emphasized that Black women experience rates of obesity differently from other races despite income or education level that was predominantly cited to be secondary to stress. Stress was voiced as a considerable contributor to disordered eating, decreased engagement in physical activity, and lack of motivation
Counter-Hypothetical Particle Filters for Single Object Pose Tracking
Particle filtering is a common technique for six degree of freedom (6D) pose
estimation due to its ability to tractably represent belief over object pose.
However, the particle filter is prone to particle deprivation due to the
high-dimensional nature of 6D pose. When particle deprivation occurs, it can
cause mode collapse of the underlying belief distribution during importance
sampling. If the region surrounding the true state suffers from mode collapse,
recovering its belief is challenging since the area is no longer represented in
the probability mass formed by the particles. Previous methods mitigate this
problem by randomizing and resetting particles in the belief distribution, but
determining the frequency of reinvigoration has relied on hand-tuning abstract
heuristics. In this paper, we estimate the necessary reinvigoration rate at
each time step by introducing a Counter-Hypothetical likelihood function, which
is used alongside the standard likelihood. Inspired by the notions of
plausibility and implausibility from Evidential Reasoning, the addition of our
Counter-Hypothetical likelihood function assigns a level of doubt to each
particle. The competing cumulative values of confidence and doubt across the
particle set are used to estimate the level of failure within the filter, in
order to determine the portion of particles to be reinvigorated. We demonstrate
the effectiveness of our method on the rigid body object 6D pose tracking task.Comment: International Conference on Robotics and Automation (ICRA) 202
SUREFARM- Towards SUstainable and REsilient EU FARMing systems
Modern agricultural systems develop in the face
of changes at both a global and national level.
While arable farming is a highly competitive and
strategic sector of UK agriculture, it has to deal
with and respond to a range of global challenges
such as climate change and the imperative to
reduce its carbon footprint, the price volatility of
a globalised food system, extreme weather
events, labour shortages and more recently the
COVID-19 Pandemic. This summary focuses on a selected set of outputs from SURE-Farm and the work specifically
undertaken by CCRI
SUREFARM- Towards SUstainable and REsilient EU FARMing systems
Modern agricultural systems develop in the face
of changes at both a global and national level.
While arable farming is a highly competitive and
strategic sector of UK agriculture, it has to deal
with and respond to a range of global challenges
such as climate change and the imperative to
reduce its carbon footprint, the price volatility of
a globalised food system, extreme weather
events, labour shortages and more recently the
COVID-19 Pandemic. This summary focuses on a selected set of outputs from SURE-Farm and the work specifically
undertaken by CCRI
Reports of Negative Interactions with Healthcare Providers among Transgender, Nonbinary, and Gender-Expansive People assigned Female at Birth in the United States: Results from an Online, Cross-Sectional Survey
Over one million people in the United States are transgender, nonbinary, or gender expansive (TGE). TGE individuals, particularly those who have pursued gender-affirming care, often need to disclose their identities in the process of seeking healthcare. Unfortunately, TGE individuals often report negative experiences with healthcare providers (HCPs). We conducted a cross-sectional online survey of 1684 TGE people assigned female or intersex at birth in the United States to evaluate the quality of their healthcare experiences. Most respondents (70.1%, n = 1180) reported at least one negative interaction with an HCP in the past year, ranging from an unsolicited harmful opinion about gender identity to physical attacks and abuse. In an adjusted logistic regression model, those who had pursued gender-affirming medical care (51.9% of the sample, n = 874) had 8.1 times the odds (95% CI: 4.1-17.1) of reporting any negative interaction with an HCP in the past year, compared to those who had not pursued gender-affirming care, and tended to report a higher number of such negative interactions. These findings suggest that HCPs are failing to create safe, high-quality care interactions for TGE populations. Improving care quality and reducing bias is crucial for improving the health and well-being of TGE people
D5.3 Resilience assessment of current farming systems across the European Union
For improving sustainability and resilience of EU farming system, the current state needs to be
assessed, before being able to move on to future scenarios. Assessing sustainability and resilience
of farming systems is a multi-faceted research challenge in terms of the scientific domains and
scales of integration (farm, household, farming system level) that need to be covered. Hence, in
SURE-Farm, multiple approaches are used to evaluate current sustainability and resilience and its
underlying structures and drivers. To maintain consistency across the different approaches, all
approaches are connected to a resilience framework which was developed for the unique
purposes of SURE-Farm. The resilience framework follows five steps: 1) the farming system
(resilience of what?), 2) challenges (resilience to what?), 3) functions (resilience for what
purpose?), 4) resilience capacities, 5) resilience attributes (what enhances resilience?). The
framework was operationalized in 11 case studies across the EU.
Applied approaches differ in disciplinary orientation and the farming system process they focus
on. Three approaches focus on risk management: 1) a farm survey with a main focus on risk
management and risk management strategies, 2) interviews on farmers’ learning capacity and
networks of influence, and 3) Focus Groups on risk management. Two approaches address farm
demographics: 4) interviews on farm demographics, and 5) AgriPoliS Focus Group workshops on
structural change of farming systems from a (farm) demographics perspective. One approach
applied so far addresses governance: 6) the Resilience Assessment Tool that evaluates how
policies and legislation support resilience of farming systems. Two methods address agricultural
production and delivery of public and private goods: 7) the Framework of Participatory Impact
Assessment for sustainable and resilient farming systems (FoPIA-SURE-Farm), aiming to integrate
multiple perspectives at farming system level, and 8) the Ecosystem Services assessment that
evaluates the delivery of public and private goods. In a few case studies, additional methods were
applied. Specifically, in the Italian case study, additional statistical approaches were used to
increase the support for risk management options (Appendix A and Appendix B).
Results of the different methods were compared and synthesized per step of the resilience
framework. Synthesized results were used to determine the position of the farming system in the
adaptive cycle, i.e. in the exploitation, conservation, release, or reorganization phase. Dependent
on the current phase of the farming system, strategies for improving sustainability and resilience
were developed.
Results were synthesized around the three aspects characterizing the SURE-Farm framework, i.e.
(i) it studies resilience at the farming system level, (ii) considers three resilience capacities, and
(iii) assesses resilience in the context of the (changing) functions of the system.
(i) Many actors are part of the farming system. However, resilience-enhancing strategies are
mostly defined at the farm level. In each farming system multiple actors are considered to
be part of the system, such as consultants, neighbors, local selling networks and nature
organizations. The number of different farming system actors beyond the focal farmers
varies between 4 (in French beef and Italian hazelnut systems) and 14 (large-scale arable
systems in the UK). These large numbers of actors illustrate the relevance of looking at
farming system level rather than at farm level. It also suggests that discussions about
resilience and future strategies need to embrace all of these actors.
(ii) At system level there is a low perceived capacity to transform. Yet, most systems appear to
be at the start of a period in which (incremental) transformation is required. At system level,
the capacity to transform is perceived to be relatively low, except in the Romanian mixed
farming system. The latter may reflect a combination of ample room to grow and a relatively
stable environment (especially when compared to the past 30 to 50 years). The relatively
low capacity to transform in the majority of systems is not in line with the suggestion that
most systems are at the start of (incremental) transformation, or, at least, reached a
situation in which they can no longer grow. Further growth is only deemed possible in the
Belgium dairy, Italian hazelnut, Polish fruit and Romanian mixed farming systems.
(iii) System functions score well with regard to the delivery of high-quality and safe food but face
problems with quality of rural life and protecting biodiversity. Resilience capacities can only
be understood in the context of the functions to be delivered by a farming system. We find
that across all systems required functions are a mix of private and public goods. With regard
to the capacity to deliver private goods, all systems perform well with respect to high-quality
and safe food. Viability of farm income is regarded moderate or low in the livestock systems
in Belgium (dairy), France (beef) and Sweden (broilers), and the fruit farming system in
Poland. Across all functions, attention is especially needed for the delivery of public goods.
More specifically the quality of rural life and infrastructure are frequently classified as being
important, but currently performing bad. Despite the concerns about the delivery of public
goods, many future strategies still focus on improving the delivery of private goods.
Suggestions in the area of public goods include among others the implementation of
conservation farming in the UK arable system, improved water management in the Italian
hazelnut system, and introduction of technologies which reduce the use of herbicides in
Polish fruit systems. It is questionable whether these are sufficient to address the need to
improve the maintenance of natural resources, biodiversity and attractiveness of rural
areas. With regard to the changing of functions over time, we did not find evidence for this
in our farming systems
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