G protein-coupled receptor kinase-2 (GRK-2) controls exploration through neuropeptide signaling in Caenorhabditis elegans.

Animals alter their behavior in manners that depend on environmental conditions as well as their developmental and metabolic states. For example, C. elegans is quiescent during larval molts or during conditions of satiety. By contrast, worms enter an exploration state when removed from food. Sensory perception influences movement quiescence (defined as a lack of body movement), as well as the expression of additional locomotor states in C. elegans that are associated with increased or reduced locomotion activity, such as roaming (exploration behavior) and dwelling (local search). Here we find that movement quiescence is enhanced, and exploration behavior is reduced in G protein-coupled receptor kinase grk-2 mutant animals. grk-2 was previously shown to act in chemosensation, locomotion, and egg-laying behaviors. Using neuron-specific rescuing experiments, we show that GRK-2 acts in multiple ciliated chemosensory neurons to control exploration behavior. grk-2 acts in opposite ways from the cGMP-dependent protein kinase gene egl-4 to control movement quiescence and exploration behavior. Analysis of mutants with defects in ciliated sensory neurons indicates that grk-2 and the cilium-structure mutants act in the same pathway to control exploration behavior. We find that GRK-2 controls exploration behavior in an opposite manner from the neuropeptide receptor NPR-1 and the neuropeptides FLP-1 and FLP-18. Finally, we show that secretion of the FLP-1 neuropeptide is negatively regulated by GRK-2 and that overexpression of FLP-1 reduces exploration behavior. These results define neurons and molecular pathways that modulate movement quiescence and exploration behavior.

Dinoflagellate vertical migration fuels an intense red tide.

Harmful algal blooms (HABs) are increasing globally, causing economic, human health, and ecosystem harm. In spite of the frequent occurrence of HABs, the mechanisms responsible for their exceptionally high biomass remain imperfectly understood. A 50-y-old hypothesis posits that some dense blooms derive from dinoflagellate motility: organisms swim upward during the day to photosynthesize and downward at night to access deep nutrients. This allows dinoflagellates to outgrow their nonmotile competitors. We tested this hypothesis with in situ data from an autonomous, ocean-wave-powered vertical profiling system. We showed that the dinoflagellate Lingulodinium polyedra's vertical migration led to depletion of deep nitrate during a 2020 red tide HAB event. Downward migration began at dusk, with the maximum migration depth determined by local nitrate concentrations. Losses of nitrate at depth were balanced by proportional increases in phytoplankton chlorophyll concentrations and suspended particle load, conclusively linking vertical migration to the access and assimilation of deep nitrate in the ocean environment. Vertical migration during the red tide created anomalous biogeochemical conditions compared to 70 y of climatological data, demonstrating the capacity of these events to temporarily reshape the coastal ocean's ecosystem and biogeochemistry. Advances in the understanding of the physiological, behavioral, and metabolic dynamics of HAB-forming organisms from cutting-edge observational techniques will improve our ability to forecast HABs and mitigate their consequences in the future.

Parallel quorum-sensing system in Vibrio cholerae prevents signal interference inside the host.

Many bacteria use quorum sensing (QS) to regulate virulence factor production in response to changes in population density. QS is mediated through the production, secretion, and detection of signaling molecules called autoinducers (AIs) to modulate population-wide behavioral changes. Four histidine kinases, LuxPQ, CqsS, CqsR and VpsS, have been identified in Vibrio cholerae as QS receptors to activate virulence gene expression at low cell density. Detection of AIs by these receptors leads to virulence gene repression at high cell density. The redundancy among these receptors is puzzling since any one of the four receptors is sufficient to support colonization of V. cholerae in the host small intestine. It is believed that one of the functions of such circuit architecture is to prevent interference on any single QS receptor. However, it is unclear what natural molecules can interfere V. cholerae QS and in what environment interference is detrimental. We show here mutants expressing only CqsR without the other three QS receptors are defective in colonizing the host large intestine. We identified ethanolamine, a common intestinal metabolite that can function as a chemical source of QS interference. Ethanolamine specifically interacts with the ligand-binding CACHE domain of CqsR and induces a premature QS response in V. cholerae mutants expressing only CqsR without the other three QS receptors. The effect of ethanolamine on QS gene expression and host colonization is abolished by mutations that disrupt CqsR signal sensing. V. cholerae defective in producing ethanolamine is still proficient in QS, therefore, ethanolamine functions only as an external cue for CqsR. Our findings suggest the inhibitory effect of ethanolamine on CqsR could be a possible source of QS interference but is masked by the presence of the other parallel QS pathways, allowing V. cholerae to robustly colonize the host.

A mechanism for sickness sleep: lessons from invertebrates.

During health, animal sleep is regulated by an internal clock and by the duration of prior wakefulness. During sickness, sleep is regulated by cytokines released from either peripheral cells or from cells within the nervous system. These cytokines regulate central nervous system neurons to induce sleep. Recent research in the invertebrates Caenorhabditis elegans and Drosophila melanogaster has led to new insights into the mechanism of sleep during sickness. Sickness is triggered by exposure to environments such as infection, heat, or ultraviolet light irradiation, all of which cause cellular stress. Epidermal growth factor is released from stressed cells and signals to activate central neuroendocrine cell(s). These neuron(s) release neuropeptides including those containing an amidated arginine(R)-phenylalanine(F) motif at their C-termini (RFamide peptides). Importantly, mechanisms regulating sickness sleep are partially distinct from those regulating healthy sleep. We will here review key findings that have elucidated the central neuroendocrine mechanism of sleep during sickness. Adaptive mechanisms employed in the control of sickness sleep may play a role in correcting cellular homeostasis after various insults. We speculate that these mechanisms may play a maladaptive role in human pathological conditions such as in the fatigue and anorexia associated with autoimmune diseases, with major depression, and with unexplained chronic fatigue.

Deconstructing Demand: The Anthropogenic and Climatic Drivers of Urban Water Consumption.

Cities in drought prone regions of the world such as South East Australia are faced with escalating water scarcity and security challenges. Here we use 72 years of urban water consumption data from Melbourne, Australia, a city that recently overcame a 12 year "Millennium Drought", to evaluate (1) the relative importance of climatic and anthropogenic drivers of urban water demand (using wavelet-based approaches) and (2) the relative contribution of various water saving strategies to demand reduction during the Millennium Drought. Our analysis points to conservation as a dominant driver of urban water savings (69%), followed by nonrevenue water reduction (e.g., reduced meter error and leaks in the potable distribution system; 29%), and potable substitution with alternative sources like rain or recycled water (3%). Per-capita consumption exhibited both climatic and anthropogenic signatures, with rainfall and temperature explaining approximately 55% of the variance. Anthropogenic controls were also strong (up to 45% variance explained). These controls were nonstationary and frequency-specific, with conservation measures like outdoor water restrictions impacting seasonal water use and technological innovation/changing social norms impacting lower frequency (baseline) use. The above-noted nonstationarity implies that wavelets, which do not assume stationarity, show promise for use in future predictive models of demand.

Recurrent modification of a conserved cis-regulatory element underlies fruit fly pigmentation diversity.

The development of morphological traits occurs through the collective action of networks of genes connected at the level of gene expression. As any node in a network may be a target of evolutionary change, the recurrent targeting of the same node would indicate that the path of evolution is biased for the relevant trait and network. Although examples of parallel evolution have implicated recurrent modification of the same gene and cis-regulatory element (CRE), little is known about the mutational and molecular paths of parallel CRE evolution. In Drosophila melanogaster fruit flies, the Bric-à-brac (Bab) transcription factors control the development of a suite of sexually dimorphic traits on the posterior abdomen. Female-specific Bab expression is regulated by the dimorphic element, a CRE that possesses direct inputs from body plan (ABD-B) and sex-determination (DSX) transcription factors. Here, we find that the recurrent evolutionary modification of this CRE underlies both intraspecific and interspecific variation in female pigmentation in the melanogaster species group. By reconstructing the sequence and regulatory activity of the ancestral Drosophila melanogaster dimorphic element, we demonstrate that a handful of mutations were sufficient to create independent CRE alleles with differing activities. Moreover, intraspecific and interspecific dimorphic element evolution proceeded with little to no alterations to the known body plan and sex-determination regulatory linkages. Collectively, our findings represent an example where the paths of evolution appear biased to a specific CRE, and drastic changes in function were accompanied by deep conservation of key regulatory linkages.

Hepatic FGF21 production is increased in late pregnancy in the mouse.

Female mammals call on hormonally driven metabolic adaptations to meet the energy demand of late pregnancy and lactation. These maternal adaptations preserve limiting nutrients and promote their transfer to the uterus during pregnancy or mammary gland during lactation. The novel metabolic hormone fibroblast growth factor-21 (FGF21) was recently shown to increase suddenly at the onset of lactation in dairy cows, but whether FGF21 is induced during the reproductive cycle of other mammals is unknown. To start addressing this question, we studied subsets of mice when virgin (V), on day 18 of pregnancy (P18) and on lactation day 1 (L1), L5 and L14. Plasma FGF21 increased from nearly undetectable levels to over 8 ng/ml between V and P18 and returned to V levels by L1. Gene expression studies showed that liver was the major source of plasma FGF21 at P18 with little or no contribution from other known expressing tissues or from the developing placenta and mammary epithelial cells. The increased FGF21 production at P18 was dissociated from plasma nonesterified fatty acids and liver lipids, unlike that seen in fasted V mice. Changes in FGF21 signaling components in target tissues were modest except for reduced ß-Klotho and FGFR1c expression in P18 adipose tissue. The placenta expressed both ß-Klotho and FGFR1c, raising the possibility that it responds to FGF21. In conclusion, maternal FGF21 is increased when products of conception account for ∼ 40% of maternal weight, suggesting that FGF21 orchestrates some of the adaptations needed to meet the energy demand of late pregnancy.

Small drains, big problems: the impact of dry weather runoff on shoreline water quality at enclosed beaches.

Enclosed beaches along urban coastlines are frequent hot spots of fecal indicator bacteria (FIB) pollution. In this paper we present field measurements and modeling studies aimed at evaluating the impact of small storm drains on FIB pollution at enclosed beaches in Newport Bay, the second largest tidal embayment in Southern California. Our results suggest that small drains have a disproportionate impact on enclosed beach water quality for five reasons: (1) dry weather surface flows (primarily from overirrigation of lawns and ornamental plants) harbor FIB at concentrations exceeding recreational water quality criteria; (2) small drains can trap dry weather runoff during high tide, and then release it in a bolus during the falling tide when drainpipe outlets are exposed; (3) nearshore turbulence is low (turbulent diffusivities approximately 10(-3) m(2) s(-1)), limiting dilution of FIB and other runoff-associated pollutants once they enter the bay; (4) once in the bay, runoff can form buoyant plumes that further limit vertical mixing and dilution; and (5) local winds can force buoyant runoff plumes back against the shoreline, where water depth is minimal and human contact likely. Outdoor water conservation and urban retrofits that minimize the volume of dry and wet weather runoff entering the local storm drain system may be the best option for improving beach water quality in Newport Bay and other urban-impacted enclosed beaches.

Why may patients with spinal cord injury be overlooked for obesity screening in the Veterans Health Administration? Qualitative research of the perspectives of patients and healthcare providers.

PURPOSE: We sought to describe factors influencing reduced rates of obesity screening for patients with spinal cord injury (SCI) in the United States Veterans Health Administration (VA) and to foster potential solutions. MATERIALS AND METHODS: Semi-structured interviews with healthcare providers and patients with SCI who were recruited nationally from diverse VAs. We performed rapid qualitative analysis using content analysis of interview data. RESULTS: There were 36 providers and 37 patients. We identified provider, patient, and system level barriers to obesity screening for individuals with SCI. Overarching barriers involved provider and patient perceptions that obesity screening is a low priority compared to other health conditions, and body mass index is of low utility. Other obesity screening barriers were related to measuring weight (i.e., insufficient equipment, unknown wheelchair weight, staffing shortages, measurement errors, reduced access to annual screening, insufficient time, patient preference not to be weighed) and measuring height (i.e., insufficient guidance and equipment to this population, measurement errors). CONCLUSIONS: Barriers to obesity screenings exist for patients with SCI receiving care in VA. Healthcare provider and patient interviews suggest possible solutions, including standardizing height and weight measurement processes, ensuring equipment availability in clinics, clarifying guidelines, and offering support to providers and patients.IMPLICATIONS FOR REHABILITATIONIndividuals with spinal cord injury (SCI) have higher rates of obesity, but are often overlooked for annual obesity screening, even in clinic settings designed to care for individuals with SCI.Results may help tailor guidelines/education for healthcare and rehabilitation providers offering them guidance for improving obesity screening for individuals with SCI by standardizing weight and height measurement and documentation. To facilitate this, findings highlight the need for resources, such as ensuring clinics have necessary equipment, and increasing patient access to support and equipment.Improving the provision of obesity screening for individuals with SCI is necessary to improve health outcomes and patient satisfaction with care.

Nutrition and eating beliefs and behaviors among individuals with spinal cord injuries and disorders: Healthy or misconceived?

PURPOSE/OBJECTIVE: Nutrition knowledge, beliefs, and behaviors have important implications for managing and preventing chronic and injury-related secondary conditions in persons with spinal cord injuries and disorders (SCI/D). Yet, the unique dietary and nutritional needs and recommendations specific to individuals with SCI/D and their eating beliefs and behaviors have been understudied. Aim is to describe nutrition and eating beliefs and behaviors from the perspectives of individuals with SCI/D. RESEARCH METHOD/DESIGN: Descriptive qualitative design using in-depth semistructured interviews with a national sample of veterans with SCI/D (n = 33). Audio-recorded and transcribed verbatim transcripts were coded and analyzed using thematic analysis. RESULTS: Participants were male (61%), aged 29-84 years, and 55% had tetraplegia. Five key themes were identified: extreme fasting/caloric restriction, perceived healthy eating behaviors, perceived unhealthy eating behaviors, modified eating behaviors due to SCI/D-related symptoms, and food/preparation choices based on abilities/independence and access. CONCLUSIONS/IMPLICATIONS: Nutrition among veterans with SCI/D may be impacted by many factors, such as nutrition knowledge and beliefs/behaviors about "healthy" and "unhealthy" nutrition, fasting, caloric restriction, imbalanced intake of macro- and micronutrients, overconsumption relative to energy needs, injury-related secondary complications, postinjury body composition and function changes, impairments related to satiety and hunger signals, and difficulty in obtaining and preparing food. Study findings provide many areas that would benefit from intervention. Findings can be used to inform ideal nutrition and healthy eating beliefs and behaviors which are important because nutritional inadequacies can lead to diet-related diseases, may exacerbate SCI secondary conditions, and lead to poor overall health. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Economic and biophysical limits to seaweed farming for climate change mitigation.

Net-zero greenhouse gas (GHG) emissions targets are driving interest in opportunities for biomass-based negative emissions and bioenergy, including from marine sources such as seaweed. Yet the biophysical and economic limits to farming seaweed at scales relevant to the global carbon budget have not been assessed in detail. We use coupled seaweed growth and technoeconomic models to estimate the costs of global seaweed production and related climate benefits, systematically testing the relative importance of model parameters. Under our most optimistic assumptions, sinking farmed seaweed to the deep sea to sequester a gigaton of CO2 per year costs as little as US$480 per tCO2 on average, while using farmed seaweed for products that avoid a gigaton of CO2-equivalent GHG emissions annually could return a profit of $50 per tCO2-eq. However, these costs depend on low farming costs, high seaweed yields, and assumptions that almost all carbon in seaweed is removed from the atmosphere (that is, competition between phytoplankton and seaweed is negligible) and that seaweed products can displace products with substantial embodied non-CO2 GHG emissions. Moreover, the gigaton-scale climate benefits we model would require farming very large areas (>90,000 km2)-a >30-fold increase in the area currently farmed. Our results therefore suggest that seaweed-based climate benefits may be feasible, but targeted research and demonstrations are needed to further reduce economic and biophysical uncertainties.

The impact of the COVID-19 pandemic on individuals living with spinal cord injury: A qualitative study.

PURPOSE/OBJECTIVE: To explore the impact of the COVID-19 pandemic as experienced and reported by individuals living with a spinal cord injury (SCI). RESEARCH METHOD/DESIGN: Descriptive qualitative design using in-depth semistructured interviews with individuals with SCI (n = 33) followed by thematic analysis. RESULTS: Three main themes described impacts of the COVID-19 pandemic. (a) Impact on health care use; subthemes elaborated that this was attributable to in-person health care facility restrictions or individual decisions to delay care. Individuals with SCI experienced lapses in primary and SCI-specialty care, rehabilitation/therapy services, and home care, but some made use of telehealth services. (b) Impact on weight and/or weight management lifestyle behaviors; subthemes discussed that engagement in physical activity declined because of fitness center closures, recreational activity cancellations, and safety precautions limiting community-based and outdoor activities. The pandemic disrupted participants' independence in purchasing and making preferred food selections which impacted healthy eating. Participants ate due to boredom, at nonmealtimes, and consumed unhealthy foods during the pandemic. (c) Impact on psychosocial factors; included subthemes noting reduced social interactions, social participation, and ability to pursue pastimes with family, friends, and groups they belonged to. The pandemic also triggered emotional reactions such as worry, fear, doubt, demotivation, and feelings of social isolation. CONCLUSIONS: Our findings highlight the magnitude of consequences faced by individuals with SCI when restrictions to health care, healthy lifestyle endeavors, and social participation occurred during the COVID-19 pandemic. Findings may inform SCI health care providers on what is needed in response to future public health or natural disaster crises. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Interaction between increasing body mass index and spinal cord injury to the probability of developing a diagnosis of nonalcoholic fatty liver disease.

Background: The prevalence of obesity and comorbidities is high in the population with spinal cord injury (SCI). We sought to determine the effect of SCI on the functional form of the relationship between body mass index (BMI) and risk of developing nonalcoholic fatty liver disease (NAFLD), and assess whether SCI-specific mapping of BMI to risk of developing NAFLD is needed. Methods: Longitudinal cohort study comparing Veterans Health Administration patients with a diagnosis of SCI to a 1:2 matched control group without SCI. The relationship between BMI and development of NAFLD at any time was assessed with propensity score matched Cox regression models; NAFLD development at 10-year with a propensity score matched logistic model. The positive predictive value of developing NAFLD at 10 years was calculated for BMI 19-45 kg/m2. Results: 14,890 individuals with SCI met study inclusion criteria, and 29,780 Non-SCI individuals in matched control group. Overall, 9.2% in SCI group and 7.3% in Non-SCI group developed NAFLD during the study period. A logistic model assessing the relationship between BMI and the probability of developing a diagnosis of NAFLD demonstrated that the probability of developing disease increased as BMI increased in both cohorts. The probability was significantly higher in the SCI cohort at each BMI threshold (p < 0.01), and increased at a higher rate compared with the Non-SCI cohort as BMI increased 19-45 kg/m2. Positive predictive value for developing a diagnosis of NAFLD was higher in the SCI group for any given BMI threshold from 19 kg/m2 to BMI 45 kg/m2. Conclusions: The probability of developing NAFLD is greater in individuals with SCI than without SCI, at every BMI level 19 kg/m2 to 45 kg/m2. Individuals with SCI may warrant a higher level of suspicion and closer screening for NAFLD. The association of SCI and BMI is not linear.

Mapping the PIK3CA-related overgrowth spectrum (PROS) patient and caregiver journey using a patient-centered approach.

BACKGROUND: PROS disorders are driven by somatic, gain-of-function mutations in PIK3CA that result in hyperactivation of the phosphatidylinositol-3-kinase (PI3K) signaling pathway. PROS encompasses a broad spectrum of overlapping phenotypes (including overgrowth and vascular malformations) that vary significantly in their severity; every case is unique, leading to different, complex experiences. Here, we aim to describe the PROS experience from the patients' and caregivers' points of view, from onset to diagnosis to treatment and support. RESULTS: The PROS patient journey was developed using a literature review, an ethnography study, health care professional (HCP) research, and social listening. It was then validated with patients, caregivers, and patient advocates. Physician research included 94 PROS centers and other vascular anomaly centers throughout the United States and Europe. Ethnographic research included 24 patients, caregivers, and/or advocates; selected data from 223 patients were reviewed. Key priority areas of need were identified, along with barriers to and potential enablers of quality care. Visual mapping of the PROS patient and family journey was developed to identify key personal health and system issues, and opportunities for improvements throughout patients' lifespans. Maps were also developed for 3 specific conditions: Klippel-Trénaunay syndrome (K-T); congenital lipomatous overgrowth, vascular malformations, epidermal nevi, scoliosis/skeletal and spinal anomalies (CLOVES) syndrome; and megalencephaly-capillary malformation syndrome (M-CM). Overall, most patients with PROS conditions and their families struggle with a long path to diagnosis, access to genetic testing, and finding qualified specialists. Following diagnosis, patients and families are frequently challenged with major medical events, comorbidities, unpredictability, frequent hospitalization, impact on school and work, the need for multidisciplinary care, unwanted attention, adverse impact on mental and emotional health, and financial pressures. Lack of effective pain management emerged as a substantial issue. Challenges and barriers to quality care shift throughout patients' lifespans; transition from pediatric to adult care can be especially difficult. CONCLUSIONS: This patient journey in PROS was created in collaboration with patients, caregivers, and advocates as key partners. This novel methodology, which could be applied elsewhere, can more accurately identify areas of unmet need, barriers to care, education topics, and assist HCPs to understand the patient and family perspective.

Rates, Variability, and Predictors of Screening for Obesity: Are Individuals with Spinal Cord Injury Being Overlooked?

INTRODUCTION: Individuals with spinal cord injury (SCI) are vulnerable to obesity. Annual obesity screening using body mass index (BMI) is the standard of care mandated by US Veterans Health Administration (VHA) guidelines. Our objective was to determine the rates, variability, and predictors of guideline-concordant annual screening for obesity, given potential challenges of height and weight measurements in individuals with SCI. METHODS: This is a cross-sectional retrospective study using US national VA databases. We identified all VHA patients with chronic SCI in the fiscal year (FY) 2019, their treating facility and frequency of recorded height and weight. We applied mixed-effects logistic regression models to assess associations between annual BMI screening and patient- and facility-level characteristics. RESULTS: Of 20,978 individuals with chronic SCI in VHA in FY19, guideline-concordant annual BMI screening was lacking in 37.9%. Accounting for facility-level factors (geographic region, SCI facility type, volume of patients with SCI treated at the facility), a mixed-effects logistic regression model demonstrated that lack of annual obesity screening was significantly associated with older patient age (p < 0.001) and fewer outpatient encounters (p < 0.001) but not other patient-level factors such as sex, race, level of injury, or rurality. The rate of obesity screening among different facilities within VHA varied widely from 11.1% to 75.7%. CONCLUSION: A large proportion of persons with SCI receiving care in VHA do not receive guideline-concordant annual obesity screening, an especially acute problem in some facilities. Older patients with fewer outpatient encounters are more likely to be missed. To inform the design of interventions to improve identification and documentation of obesity, further study is needed to assess potential barriers to obesity screening in the population with SCI.

Physical and emotional consequences of excess weight as experienced by individuals with spinal cord injuries.

CONTEXT/OBJECTIVE: Excess weight has the potential to carry a substantial physical and emotional burden. A better understanding of perceived consequences of excess weight may facilitate the development of patient-centered programs and interventions to promote weight management efforts in persons with spinal cord injury (SCI). The study objective was to describe consequences of excess weight from the personal perspectives of individuals with SCI. DESIGN: Descriptive qualitative design using in-depth semi-structured interviews and thematic analysis. SETTING: Veterans Health Administration (VHA) SCI System of Care. PARTICIPANTS: Individuals with SCI (n-33). OUTCOME MEASURES: Key themes from thematic analysis. RESULTS: Participants were male (61%), ranged from 29 to 84 years of age, and about half had tetraplegia (55%). Five themes were identified that demonstrate negative consequences of excess weight experienced by individuals with SCI, including: (1) physical health conditions (including chronic conditions and SCI secondary conditions), (2) physical symptoms (such as pain, discomfort, and fatigue), (3) movement challenges, (4) appearance-related concerns, and (5) emotional impacts. CONCLUSIONS: Carrying excess weight is concerning to individuals with SCI and in terms of consequences such onset or exacerbation of chronic conditions, SCI secondary conditions, physical symptoms, e.g. pain, movement impairment (including hampered mobility, difficult transfers and self-care), image/appearance concerns (e.g. body image, clothing misfit), and negative emotions (e.g. unhappy, sad, depressed). Our findings may inform SCI healthcare providers about the consequences of excess weight as experienced by individuals with SCI, highlighting what matters most to persons with SCI and guiding a patient-centered approach to weight management in this population.

Turbulence and Coral Reefs.

The interaction of coral reefs, both chemically and physically, with the surrounding seawater is governed, at the smallest scales, by turbulence. Here, we review recent progress in understanding turbulence in the unique setting of coral reefs-how it influences flow and the exchange of mass and momentum both above and within the complex geometry of coral reef canopies. Flow above reefs diverges from canonical rough boundary layers due to their large and highly heterogeneous roughness and the influence of surface waves. Within coral canopies, turbulence is dominated by large coherent structures that transport momentum both into and away from the canopy, but it is also generated at smaller scales as flow is forced to move around branches or blades, creating wakes. Future work interpreting reef-related observations or numerical models should carefully consider the influence that spatial variation has on momentum and scalar flux.

Intravenous lidocaine as a non-opioid adjunct analgesic for traumatic rib fractures.

INTRODUCTION: Pain management is the pillar of caring for patients with traumatic rib fractures. Intravenous lidocaine (IVL) is a well-established non-opioid analgesic for post-operative pain, yet its efficacy has yet to be investigated in trauma patients. We hypothesized that IVL is associated with decreased inpatient opioid requirements among patients with rib fractures. METHODS: We retrospectively evaluated adult patients presenting to our Level 1 trauma center with isolated chest wall injuries. After 1:1 propensity score matching patients who received vs did not receive IVL, we compared the two groups' average daily opioid use, opioid use in the last 24 hours of admission, and pain scores during admissions hours 24-48. We performed multivariable linear regression for these outcomes (with sensitivity analysis for the opioid use outcomes), adjusting for age as a moderating factor and controlling for hospital length of stay and injury severity. RESULTS: We identified 534 patients, among whom 226 received IVL. Those who received IVL were older and had more serious injury. Compared to propensity-score matched patients who did not receive IVL, patients who received IVL had similar average daily opioid use and pain scores, but 40% lower opioid use during the last 24 hours of admission (p = 0.002). Multivariable regression-with and without sensitivity analysis-did not show an effect of IVL on any outcomes. CONCLUSION: IVL was crudely associated with decreased opioid requirements in the last 24 hours of admission, the time period associated with opioid use at 90 days post-discharge. However, we did not observe beneficial effects of IVL on multivariable adjusted analyses; we are conducting a randomized control trial to further evaluate IVL's opioid-sparing effects for patients with rib fractures.

Quantitative imaging of sleep behavior in Caenorhabditis elegans and larval Drosophila melanogaster.

Sleep is nearly universal among animals, yet remains poorly understood. Recent work has leveraged simple model organisms, such as Caenorhabditis elegans and Drosophila melanogaster larvae, to investigate the genetic and neural bases of sleep. However, manual methods of recording sleep behavior in these systems are labor intensive and low in throughput. To address these limitations, we developed methods for quantitative imaging of individual animals cultivated in custom microfabricated multiwell substrates, and used them to elucidate molecular mechanisms underlying sleep. Here, we describe the steps necessary to design, produce, and image these plates, as well as analyze the resulting behavioral data. We also describe approaches for experimentally manipulating sleep. Following these procedures, after ~2 h of experimental preparation, we are able to simultaneously image 24 C. elegans from the second larval stage to adult stages or 20 Drosophila larvae during the second instar life stage at a spatial resolution of 10 or 27 µm, respectively. Although this system has been optimized to measure activity and quiescence in Caenorhabditis larvae and adults and in Drosophila larvae, it can also be used to assess other behaviors over short or long periods. Moreover, with minor modifications, it can be adapted for the behavioral monitoring of a wide range of small animals.

Satiety behavior is regulated by ASI/ASH reciprocal antagonism.

Appropriate decision-making is essential for ensuring survival; one such decision is whether to eat. Overall metabolic state and the safety of food are the two factors we examined using C. elegans to ask whether the metabolic state regulates neuronal activities and corresponding feeding behavior. We monitored the activity of sensory neurons that are activated by nutritious (or appetitive) stimuli (ASI) and aversive stimuli (ASH) in starved vs. well-fed worms during stimuli presentation. Starvation reduces ASH activity to aversive stimuli while increasing ASI activity to nutritious stimuli, showing the responsiveness of each neuron is modulated by overall metabolic state. When we monitored satiety quiescence behavior that reflects the overall metabolic state, ablation of ASI and ASH produce the opposite behavior, showing the two neurons interact to control the decision to eat or not. This circuit provides a simple approach to how neurons handle sensory conflict and reach a decision that is translated to behavior.