Impact of reduced ignition propensity cigarette regulation on consumer smoking behavior and quit intentions: evidence from 6 waves (2004-11) of the ITC Four Country Survey

Background: Although on the decline, smoking-related fires remain a leading cause of fire death in the United States and United Kingdom and account for over 10% of fire-related deaths worldwide. This has prompted lawmakers to enact legislation requiring manufacturers to implement reduced ignition propensity (RIP) safety standards for cigarettes. The current research evaluates how implementation of RIP safety standards in different countries influenced smokers\u27 perceptions of cigarette self-extinguishment, frequency of extinguishment, and the impact on consumer smoking behaviors, including cigarettes smoked per day and planning to quit. Methods. Participants for this research come from Waves 3 through 8 of the International Tobacco Control (ITC) Four Country Survey conducted longitudinally from 2004 through 2011 in the United States, United Kingdom, Australia, and Canada. Results: Perceptions of cigarette self-extinguishment and frequency of extinguishment increased concurrently with an increase in the prevalence of RIP safety standards for cigarettes. Presence of RIP safety standards was also associated with a greater intention to quit smoking, but was not associated with the number of cigarettes smoked per day. Intention to quit was higher among those who were more likely to report that their cigarettes self-extinguish sometimes and often, but we found no evidence of an interaction between frequency of extinguishment and RIP safety standards on quit intentions. Conclusions: Overall, because these standards largely do not influence consumer smoking behavior, RIP implementation may significantly reduce the number of cigarette-related fires and the associated death and damages. Further research should assess how implementation of RIP safety standards has influenced smoking-related fire incidence, deaths, and other costs associated with smoking-related fires.<br /

Conceptualizing Ecological Responses to Dam Removal: If You Remove It, What’s to Come?

One of the desired outcomes of dam decommissioning and removal is the recovery of aquatic and riparian ecosystems. To investigate this common objective, we synthesized information from empirical studies and ecological theory into conceptual models that depict key physical and biological links driving ecological responses to removing dams. We define models for three distinct spatial domains: upstream of the former reservoir, within the reservoir, and downstream of the removed dam. Emerging from these models are response trajectories that clarify potential pathways of ecological transitions in each domain. We illustrate that the responses are controlled by multiple causal pathways and feedback loops among physical and biological components of the ecosystem, creating recovery trajectories that are dynamic and nonlinear. In most cases, short-term effects are typically followed by longer-term responses that bring ecosystems to new and frequently predictable ecological condition, which may or may not be similar to what existed prior to impoundment

An Empiricist’s Guide to Using Ecological Theory

A scientific understanding of the biological world arises when ideas about how nature works are formalized, tested, refined, and then tested again. Although the benefits of feedback between theoretical and empirical research are widely acknowledged by ecologists, this link is still not as strong as it could be in ecological research. This is in part because theory, particularly when expressed mathematically, can feel inaccessible to empiricists who may have little formal training in advanced math. To address this persistent barrier, we provide a general and accessible guide that covers the basic, step-by-step process of how to approach, understand, and use ecological theory in empirical work. We first give an overview of how and why mathematical theory is created, then outline four specific ways to use both mathematical and verbal theory to motivate empirical work, and finally present a practical tool kit for reading and understanding the mathematical aspects of ecological theory.We hope that empowering empiricists to embrace theory in their work will help move the field closer to a full integration of theoretical and empirical research

Transforming Obesity Prevention for CHILDren (TOPCHILD) Collaboration: Protocol for a Systematic Review with Individual Participant Data Meta-Analysis of Behavioural Interventions for the Prevention of Early Childhood Obesity

INTRODUCTION: Behavioural interventions in early life appear to show some effect in reducing childhood overweight and obesity. However, uncertainty remains regarding their overall effectiveness, and whether effectiveness differs among key subgroups. These evidence gaps have prompted an increase in very early childhood obesity prevention trials worldwide. Combining the individual participant data (IPD) from these trials will enhance statistical power to determine overall effectiveness and enable examination of individual and trial-level subgroups. We present a protocol for a systematic review with IPD meta-analysis to evaluate the effectiveness of obesity prevention interventions commencing antenatally or in the first year after birth, and to explore whether there are differential effects among key subgroups. METHODS AND ANALYSIS: Systematic searches of Medline, Embase, Cochrane Central Register of Controlled Trials, Cumulative Index to Nursing and Allied Health Literature (CINAHL), PsycInfo and trial registries for all ongoing and completed randomised controlled trials evaluating behavioural interventions for the prevention of early childhood obesity have been completed up to March 2021 and will be updated annually to include additional trials. Eligible trialists will be asked to share their IPD; if unavailable, aggregate data will be used where possible. An IPD meta-analysis and a nested prospective meta-analysis will be performed using methodologies recommended by the Cochrane Collaboration. The primary outcome will be body mass index z-score at age 24±6 months using WHO Growth Standards, and effect differences will be explored among prespecified individual and trial-level subgroups. Secondary outcomes include other child weight-related measures, infant feeding, dietary intake, physical activity, sedentary behaviours, sleep, parenting measures and adverse events. ETHICS AND DISSEMINATION: Approved by The University of Sydney Human Research Ethics Committee (2020/273) and Flinders University Social and Behavioural Research Ethics Committee (HREC CIA2133-1). Results will be relevant to clinicians, child health services, researchers, policy-makers and families, and will be disseminated via publications, presentations and media releases. PROSPERO REGISTRATION NUMBER: CRD42020177408

Unpacking the Behavioural Components and Delivery Features of Early Childhood Obesity Prevention Interventions in the TOPCHILD Collaboration: A Systematic Review and Intervention Coding Protocol

INTRODUCTION: Little is known about how early (eg, commencing antenatally or in the first 12 months after birth) obesity prevention interventions seek to change behaviour and which components are or are not effective. This study aims to (1) characterise early obesity prevention interventions in terms of target behaviours, delivery features and behaviour change techniques (BCTs), (2) explore similarities and differences in BCTs used to target behaviours and (3) explore effectiveness of intervention components in preventing childhood obesity. METHODS AND ANALYSIS: Annual comprehensive systematic searches will be performed in Epub Ahead of Print/MEDLINE, Embase, Cochrane (CENTRAL), CINAHL, PsycINFO, as well as clinical trial registries. Eligible randomised controlled trials of behavioural interventions to prevent childhood obesity commencing antenatally or in the first year after birth will be invited to join the Transforming Obesity in CHILDren Collaboration. Standard ontologies will be used to code target behaviours, delivery features and BCTs in both published and unpublished intervention materials provided by trialists. Narrative syntheses will be performed to summarise intervention components and compare applied BCTs by types of target behaviours. Exploratory analyses will be undertaken to assess effectiveness of intervention components. ETHICS AND DISSEMINATION: The study has been approved by The University of Sydney Human Research Ethics Committee (project no. 2020/273) and Flinders University Social and Behavioural Research Ethics Committee (project no. HREC CIA2133-1). The study\u27s findings will be disseminated through peer-reviewed publications, conference presentations and targeted communication with key stakeholders. PROSPERO REGISTRATION NUMBER: CRD42020177408

Single point mutations reveal amino acid residues important for Chromobacterium violaceum transaminase activity in the production of unnatural amino acids

Unnatural amino acids (UAAs) are chiral amines with high application potential in drug discovery and synthesis of other valuable chemicals. Biocatalysis offers the possibility to synthesise novel optically pure UAAs with different physical and chemical properties. While the biocatalytic potential of transaminases in the synthesis of UAAs has been demonstrated, there is still a need to improve the activity with non-native substrates and to understand which amino acids residues are important for activity with these UAAs. Using a rational design approach, six variants of Chromobacterium violaceum DSM30191 transaminase (CV_TA) carrying a single and one variant carrying two substitutions were generated. Among the variants with a single substitution, CV_Y168F showed a 2 to 2.6-fold increased affinity for 2-oxooctanoic acid (2-OOA) and 3-oxobutyric acid (3-OBA) methyl ester used to synthesise an ?- and ?-UAA. Analysis of the first half of the transaminase reaction showed no change in the activity with the donor (S)-1-phenylethylamine. The combination of W60C and Y168F substitutions improved the CV_TA affinity for 2-OOA 10-fold compared to the wild type. Other substitutions showed no change, or reduced activity with the tested substrates. Our findings provide structural information on CV_TA and demonstrate the potential of rational design for biosynthesis of UAA

Functional Connectivity in Raphé-Pontomedullary Circuits Supports Active Suppression of Breathing During Hypocapnic Apnea

Hyperventilation is a common feature of disordered breathing. Apnea ensues if CO2 drive is sufficiently reduced. We tested the hypothesis that medullary raphé, ventral respiratory column (VRC), and pontine neurons have functional connectivity and persistent or evoked activities appropriate for roles in the suppression of drive and rhythm during hyperventilation and apnea. Phrenic nerve activity, arterial blood pressure, end-tidal CO2, and other parameters were monitored in 10 decerebrate, vagotomized, neuromuscularly-blocked, and artificially ventilated cats. Multielectrode arrays recorded spiking activity of 649 neurons. Loss and return of rhythmic activity during passive hyperventilation to apnea were identified with the S-transform. Diverse fluctuating activity patterns were recorded in the raphé-pontomedullary respiratory network during the transition to hypocapnic apnea. The firing rates of 160 neurons increased during apnea; the rates of 241 others decreased or stopped. VRC inspiratory neurons were usually the last to cease firing or lose rhythmic activity during the transition to apnea. Mayer wave-related oscillations (0.04–0.1 Hz) in firing rate were also disrupted during apnea. Four-hundred neurons (62%) were elements of pairs with at least one hyperventilation-responsive neuron and a correlational signature of interaction identified by cross-correlation or gravitational clustering. Our results support a model with distinct groups of chemoresponsive raphé neurons contributing to hypocapnic apnea through parallel processes that incorporate disfacilitation and active inhibition of inspiratory motor drive by expiratory neurons. During apnea, carotid chemoreceptors can evoke rhythm reemergence and an inspiratory shift in the balance of reciprocal inhibition via suppression of ongoing tonic expiratory neuron activity. breathing is a remarkably robust behavior that is activated at birth and continues until death, yet the brain stem neural network controlling it is even more remarkable in its malleability. For example, talking, swallowing, and coughing are motor acts that alter the breathing pattern and, rather than simply inhibiting breathing, the neural substrate for these motor acts transiently appropriates and reconfigures the respiratory pattern generator (Bolser et al. 2011, 2013; Shannon et al. 2004). However, what about conditions when breathing stops? Hyperventilation is a component of dangerous underwater breath-holding behaviors (Boyd et al. 2015; Craig 1961) and a common feature of disordered breathing (for discussion, see Abdala et al. 2014; Dempsey 2005; Laffey and Kavanagh 2002). If the drive from CO2 is sufficiently reduced, hypocapnic apnea, a transient cessation of breathing, ensues with its attendant and potentially adverse consequences (Bitter et al. 2011; Harper et al. 2013; Javaheri and Dempsey 2013; Leung et al. 2012; Sankri-Tarbichi et al. 2009; Sankri-Tarbichi 2012). During the transition from eupneic-like breathing to hyperventilatory apnea, phrenic motoneurons (Prabhakar et al. 1986) and phasic respiratory-modulated brain stem neurons either cease to discharge or assume a tonic pattern of activity (Bainton and Kirkwood 1979; Batsel 1967; Cohen 1968; Haber et al. 1957; Nesland and Plum 1965; Orem and Vidruk 1998; St. John 1998; Sun et al. 2001, 2005). With one exception (Cohen 1968), these studies recorded neurons in the ventral respiratory column (VRC; Smith et al. 2013), one at a time. This approach precludes assessment of local connectivity within the VRC and of distributed interactions with pontine and raphé neurons of the respiratory network (Nuding et al. 2009a; Segers et al. 2008). The circuit mechanisms for hypocapnic apnea remain poorly understood. Both reduced excitatory chemoreceptor drive and active inhibitory processes may contribute to the suspended state of the respiratory central pattern generator. Peripheral chemoreceptors of the carotid body monitor changes in arterial O2 and CO2-pH (Kumar and Prabhakar 2012), and central chemoreceptors, distributed among various brain stem sites, sense brain CO2-pH (Nattie and Li 2012). Mechanisms of their joint and separate influences on pattern-generating circuits are subjects of active research (Duffin and Mateika 2013a,b; Phillipson et al. 1981; Teppema and Smith 2013a,b; Wilson and Day 2013a,b). Central chemoreceptors and their follower neurons, collectively termed chemoresponsive, may be either functionally excited or inhibited by an increase in PaCO2 (e.g., Bochorishvili et al. 2012; Dean et al. 1989; Guyenet et al. 2010; Marina et al. 2010; Nuding et al. 2009b; Ott et al. 2011, 2012; Richerson et al. 2001). Medullary raphé neurons have diverse responses to hypercapnia and acidosis: firing rates of serotonergic neurons increase (Brust et al. 2014; Iceman et al. 2013; Severson et al. 2003; Veasey et al. 1995; Wang et al. 1998, 2001), whereas GABAergic raphé neurons are functionally inhibited (Iceman et al. 2014). These results are consistent with the hypothesis that distinct populations of chemoresponsive raphé neurons produce an additive “push-pull” enhancement of breathing via excitation and disinhibition, respectively (Richerson et al. 2001), a notion similar to that proposed for baroreceptor-evoked modulation of breathing via raphé-mediated excitation and disinhibition of ventral respiratory column expiratory neurons (Lindsey et al. 1998). The distinct chemoresponsive profiles of different raphé neuron populations led us to conjecture that cells effectively excited during hypercapnia would exhibit decreased firing rates during hypocapnia and vice versa for neurons inhibited during hypercapnia. This possibility and gaps in our knowledge of network interactions motivated us to test the hypothesis that medullary raphé, VRC, and pontine neurons have functional connectivity as well as persistent and evoked activities appropriate for roles in the suppression of respiratory drive and rhythm during hyperventilation and hypocapnic apnea. Sears et al. (1982) demonstrated reciprocal tonic activation of inspiratory and expiratory motor neurons during hypocapnic apnea. A PaCO2 drive below the apneic threshold may promote expiratory activity and functionally suppress inspiration. Hypoxia associated with apnea evokes increased peripheral chemoreceptor activity, enhances or elicits tonic inspiratory motor neuron activities, and can reestablish respiratory rhythmogenesis. Fluctuations in this peripheral chemoreceptor-mediated “inspiratory shift,” operating through unknown circuit mechanisms, may contribute to periodic breathing in heart failure and central sleep apnea (Lovering et al. 2012). Our multielectrode arrays allow concurrent single-unit recordings from multiple brain stem nuclei that generate and modulate breathing. This approach is well suited for testing our hypothesis and assessment of the activity patterns of many neurons under the same conditions. Thus we recorded changes in firing rates during different chemoreceptor-evoked perturbations of breathing and evaluated spike trains for correlation features indicative of functional connectivity. Preliminary accounts of this work have been presented (Lindsey et al. 2014; Nuding et al. 2005, 2013)

Behavioral symptoms of dementia that present management difficulties in nursing homes: staff perceptions and their concordance with informant scales

The current study aimed to profile behaviors associated with dementia that pose management difficulties for staff and determine whether existing rating scales capture these reported behaviors. Staff in 17 nursing homes described the behavioral symptoms of 229 residents with predominantly moderate-severe dementia associated with management difficulties. Behaviors were categorized by an expert clinical panel and compared to items in four dementia behavior rating scales. Staff reported 59 discrete behavioral symptoms, with physically agitated, aggressive verbal, non-aggressive verbal, and aggressive physical behaviors most common, followed by resistance to care and inappropriate social and sexual behaviors. Results suggested that some scales omit important behaviors reported by staff for residents with particularly challenging behaviors. The current study highlights the clinical complexity faced by nursing home staff in managing residents with behavioral symptoms of dementia. [Journal of Gerontological Nursing, 43(1), 34-43.]