To the Editor—The North Carolina Medical Board and North Carolina Medical Society have concerns regarding the Correspondence To the Editor in the March/April 2019 issue of the North Carolina Medical Journal titled, "Aid in Dying in North Carolina" [1]. Although we recognize the beliefs shared by the individual authors were not intended to be conclusive guidance regarding the status of aid in dying (AID) in North Carolina, we feel compelled to respond with a few clarifying notes.

The authors of the correspondence opine: "In light of the legal analysis of North Carolina law, we feel confident that AID can be provided to patients who request it" and that "physicians can provide AID ... without risk of a viable criminal or disciplinary action" [1].

In all matters of medical practice, including end-of-life matters, physicians and physician assistants must meet the standards of acceptable and prevailing medical practice and the ethics of the medical profession. If the Medical Board receives a complaint related to AID, it will evaluate the complaint and determine, utilizing expert consultants, whether the physician engaged in unprofessional conduct as defined by the North Carolina Medical Practice Act.

Further, disagreement exists within the medical community regarding the role of clinicians in medical AID. In one national survey, there was no consensus about the acceptability of AID among physicians and other health care professionals caring for older adults [2]. Respondents also expressed concerns about AID applied to vulnerable populations, including those with low health literacy, low English proficiency, disability, dependency,...

North Carolina has received national attention for its approach to health care payment and delivery reform. Importantly, payment reform alone is not enough to drive systematic changes in care delivery. We highlight the importance of progress in four complementary areas to achieve system-wide payment and care reform.

For decades, government, health systems, universities, foundations, exceptional individuals, and thought leaders across North Carolina have been testing, implementing, modifying, and just plain trying new ways of improving the way we seek, receive, and experience health care.

More recently, North Carolina has been striving to not simply address the cost, efficiency, and value that are so frustratingly elusive in health care, but also recognizing that we simply need to improve the health of our residents. We have looked to interventions both compatible with and beyond health care to do this.

The National Academy of Medicine, formerly the National Institute of Medicine, since 2016 has boldly laid out Vital Directions in Health Care, focusing on 19 priority issues and recommendations for health policy to better achieve health and well-being for all Americans. They have taken their show on the road, beyond the halls of Congress and think tanks and universities to the people on the ground in states across the country to present, discuss, listen, and learn how policy recommendations come to life.

This issue of the journal highlights the National Academy of Medicine bringing its spotlight to North Carolina last November, an acknowledgment that states are often where policy is put into action, and that North Carolina has been a leader in innovating, planning, implementing, and evaluating again and again to get better and better results for our residents. Pull your chair up to the edge of the stage for a good read in the glow of the spotlight.

BACKGROUND Pregnant patients from rural counties of Western North Carolina face additional barriers when accessing comprehensive perinatal substance use disorders care at Project CARA as compared to patients local to the program in Buncombe County. We hypothesized regional patients would be less engaged in care.

METHOD Using a retrospective cohort design, univariate analyses (², t-test; P < .05) compared patients' characteristics, engagement in care, and delivery outcomes. Engagement in care, the primary outcome, was operationalized as: attendance at expected, program-specific prenatal and postpartum visits, utilization of in-house counseling, community-based and/or inpatient substance use disorders treatment, and maternal urine drug screen at delivery negative for illicit substances.

RESULTS Regional patients (n = 324) were more likely than Buncombe County patients (n = 284) to have opioid [209 (64.5%) versus 162 (57.0%)] or amphetamine/methamphetamine use disorders (25 [7.7%] versus 13 [4.6%]), but less likely to have cannabis use (19 [5.9%] versus 38 [13.4%]; P = .009) and concurrent psychiatric disorders (214 [66.0%] versus 220 [77.5%]; P = .002). Engagement at postpartum visits was the significantly different outcome between patients (110/221 [49.8%] versus 146/226 [64.6%]; P = .002).

LIMITATIONS Outcomes were available for 66.8% of regional and 79.6% of Buncombe County patients of one program in one predominately white, non-Hispanic region of the state.

CONCLUSION Contrary to our hypothesis, regional and Buncombe County women engaged in prenatal care equally. However, a more formal transition into the postpartum period is needed, especially for regional women. A "hub-and-spokes" model that extends delivery of perinatal substance use disorders care into rural communities may be more effective for engagement retention.

Studies of the former NE England coalfield in Tyneside demonstrated that heat flow perturbations in boreholes were due to the entrainment and lateral dispersion of heat from deeper in the subsurface through flooded mine workings. This work assesses the influence of historical mining on geothermal observations across Greater Glasgow. The regional heat flow for Glasgow is 60 mW m^–2 and, after correction for palaeoclimate, is estimated as c. 80 mW m^–2. An example of reduced heat flow above mine workings is observed at Hallside (c. 10 km SE of Glasgow), where the heat flow through a 352 m deep borehole is c. 14 mW m^–2. Similarly, the heat flow across the 199 m deep GGC01 borehole in the Glasgow Geothermal Energy Research Field Site is c. 44 mW m^–2. The differences between these values and the expected regional heat flow suggest a significant component of horizontal heat flow into surrounding flooded mine workings. This deduction also influences the quantification of deeper geothermal resources, as extrapolation of the temperature gradient above mine workings would underestimate the temperature at depth. Future projects should consider the influence of historical mining on heat flow when temperature datasets such as these are used in the design of geothermal developments.

Supplementary material: Background information on the chronology of historical mining at each borehole location and a summary of groundwater flow in mine workings beneath Glasgow are available at https://doi.org/10.6084/m9.figshare.c.4681100

Thematic collection: This article is part of the ‘Early Career Research’ available at: https://www.lyellcollection.org/cc/SJG-early-career-research

Thematic collection: This article is part of the ‘Early Career Researchers’ available at: https://www.lyellcollection.org/cc/SJG-early-career-research

A wide variety of intrinsic and extrinsic cues lead to cell death with unclear mechanisms. The infertility of some death mutants often hurdles the classical suppressor screens for death regulators. We have developed a transient RNA interference (RNAi)-based screen using a virus-induced gene silencing approach to understand diverse cell death pathways in Arabidopsis (Arabidopsis thaliana). One death pathway is due to the depletion of a MAP kinase (MAPK) cascade, consisting of MAPK kinase kinase 1 (MEKK1), MKK1/2, and MPK4, which depends on a nucleotide-binding site Leu-rich repeat (NLR) protein SUMM2. Silencing of MEKK1 by virus-induced gene silencing resembles the mekk1 mutant with autoimmunity and defense activation. The RNAi-based screen toward Arabidopsis T-DNA insertion lines identified SUMM2, MEKK2, and Calmodulin-binding receptor-like cytoplasmic kinase 3 (CRCK3) to be vital regulators of RNAi MEKK1-induced cell death, consistent with the reports of their requirement in the mekk1-mkk1/2-mpk4 death pathway. Similar with MEKK2, overexpression of CRCK3 caused dosage- and SUMM2-dependent cell death, and the transcripts of CRCK3 were up-regulated in mekk1, mkk1/2, and mpk4. MEKK2-induced cell death depends on CRCK3. Interestingly, CRCK3-induced cell death also depends on MEKK2, consistent with the biochemical data that MEKK2 complexes with CRCK3. Furthermore, the kinase activity of CRCK3 is essential, whereas the kinase activity of MEKK2 is dispensable, for triggering cell death. Our studies suggest that MEKK2 and CRCK3 exert concerted functions in the control of NLR SUMM2 activation and MEKK2 may play a structural role, rather than function as a kinase, in regulating CRCK3 protein stability.

The polysaccharide pectin is a major component of the plant cell wall. The pectic glycan homogalacturonan (HG) is a proportionally small but important component of a specialized seed cell wall called mucilage. HG is synthesized in a highly methylesterified form, and, following secretion, is de-methylesterified by pectin methylesterases (PMEs). The degree of methylesterification of HG determines the structural and functional properties of pectin, but how methylesterification is regulated remains largely unknown. Here, we identified two BEL1-Like homeodomain (BLH) transcription factors, BLH2 and BLH4, as positive regulators of HG de-methylesterification in Arabidopsis (Arabidopsis thaliana) seed coat mucilage. BLH2 and BLH4 were significantly expressed in mucilage secretory cells during seed mucilage production. BLH2 and BLH4 single mutants exhibited no obvious mucilage phenotype, but the blh2 blh4 double mutant displayed significantly reduced mucilage adherence to the seed. Reduced mucilage adherence in blh2 blh4 was caused by decreased PME activity in the seed coat, which increased the degree of methylesterification of HG in mucilage. The expression of several PME metabolism-related genes, including PME58, PECTIN METHYLESTERASE INHIBITOR6, SEEDSTICK, and MYB52 was significantly altered in blh2 blh4 seeds. BLH2 and BLH4 directly activated PME58 expression by binding to its TGACAGGT cis-element. Moreover, pme58 mutants exhibited reduced mucilage adherence similar to that of blh2 blh4, and the blh2 blh4 pme58 triple mutant exhibited no additional mucilage adherence defects. Furthermore, overexpression of PME58 in blh2 blh4 rescued the mucilage adherence defect. Together, these results demonstrate that BLH2 and BLH4 redundantly regulate de-methylesterification of HG in seed mucilage by directly activating PME58.

The treatment for obstructive sleep apnoea (OSA) with continuous positive airway pressure (CPAP) or mandibular advancement devices (MADs) is associated with blood pressure (BP) reduction; however, the overall effect is modest. The aim of this systematic review and meta-analysis of randomised controlled trials (RCTs) comparing the effect of such treatments on BP was to identify subgroups of patients who respond best to treatment.

The article search was performed in three different databases with specific search terms and selection criteria. From 2289 articles, we included 68 RCTs that compared CPAP or MADs with either passive or active treatment. When all the studies were pooled together, CPAP and MADs were associated with a mean BP reduction of –2.09 (95% CI –2.78– –1.40) mmHg for systolic BP and –1.92 (95% CI –2.40– –1.43) mmHg for diastolic BP and –1.27 (95% CI –2.34– –0.20) mmHg for systolic BP and –1.11 (95% CI –1.82– –0.41) mmHg for diastolic BP, respectively. The subgroups of patients who showed a greater response were those aged <60 years (systolic BP –2.93 mmHg), with uncontrolled BP at baseline (systolic BP –4.14 mmHg) and with severe oxygen desaturations (minimum arterial oxygen saturation measured by pulse oximetry <77%) at baseline (24-h systolic BP –7.57 mmHg).

Although this meta-analysis shows that the expected reduction of BP by CPAP/MADs is modest, it identifies specific characteristics that may predict a pronounced benefit from CPAP in terms of BP control. These findings should be interpreted with caution; however, they are particularly important in identifying potential phenotypes associated with BP reduction in patients treated for OSA.

Ventilatory settings are critical in mechanically ventilated extremely preterm newborn infants due to the risk of ventilation-induced lung injury (VILI) and the subsequent development of bronchopulmonary dysplasia (BPD) [1]. Positive end-expiratory pressure (PEEP) settings usually rely on blood gases, oxygen requirement, lung auscultation, evaluation of chest radiograph and assessment of the pressure/volume curves provided by ventilators. Studies of optimal PEEP settings in the surfactant-treated preterm infant in need of mechanical ventilation are limited and evidence-based clinical guidelines are sparse [2, 3]. A bedside method identifying the PEEP value that comprises maximal lung volume recruitment and minimising tissue overdistension could improve real-time optimisation of PEEP and potentially minimise the risk of VILI and BPD [4, 5].

Objective

To determine the contributions of apraxia of speech (AOS) and anomia to conversational dysfluency.

Background

Plasma cardiac troponin (cTn) elevation occurs in acute ischemic stroke and intracranial hemorrhage and can suggest a poor prognosis. Because acute cerebral venous thrombosis (CVT) might lead to venous stasis, which could result in cardiac stress, it is important to evaluate whether cTn elevation occurs in patients with CVT.

OBJECTIVES:

To describe (1) the developmental trajectories of peer victimization from 6 to 17 years of age and (2) the early childhood behaviors and family characteristics associated with the trajectories.

A 16-year-old girl presented to her primary care physician with a one-month history of decreased appetite and abdominal pain. She had normal bowel movements and no vomiting, but her periumbilical pain limited her ability to finish most meals. She had gradual weight loss over the previous 2 years, and during the previous 4 years, she intermittently received counseling for depression after the loss of her mother. Her initial physical examination and laboratory evaluation were unremarkable. She was referred to a nutritionist, adolescent medicine, and pediatric gastroenterology. Her presentation evolved over time, which ultimately led to a definitive diagnosis.

BACKGROUND:

Several studies have investigated the association of breastfeeding status with offspring mortality in Africa, but most studies were from one center only or had limited statistical power to draw robust conclusions.

Positive selection causes beneficial alleles to rise to high frequency, resulting in a selective sweep of the diversity surrounding the selected sites. Accordingly, the signature of a selective sweep in an ancestral population may still remain in its descendants. Identifying signatures of selection in the ancestor that are shared among its descendants is important to contextualize the timing of a sweep, but few methods exist for this purpose. We introduce the statistic SS-H12, which can identify genomic regions under shared positive selection across populations and is based on the theory of the expected haplotype homozygosity statistic H12, which detects recent hard and soft sweeps from the presence of high-frequency haplotypes. SS-H12 is distinct from comparable statistics because it requires a minimum of only two populations, and properly identifies and differentiates between independent convergent sweeps and true ancestral sweeps, with high power and robustness to a variety of demographic models. Furthermore, we can apply SS-H12 in conjunction with the ratio of statistics we term and to further classify identified shared sweeps as hard or soft. Finally, we identified both previously reported and novel shared sweep candidates from human whole-genome sequences. Previously reported candidates include the well-characterized ancestral sweeps at LCT and SLC24A5 in Indo-Europeans, as well as GPHN worldwide. Novel candidates include an ancestral sweep at RGS18 in sub-Saharan Africans involved in regulating the platelet response and implicated in sudden cardiac death, and a convergent sweep at C2CD5 between European and East Asian populations that may explain their different insulin responses.

BEAF (Boundary Element-Associated Factor) was originally identified as a Drosophila melanogaster chromatin domain insulator-binding protein, suggesting a role in gene regulation through chromatin organization and dynamics. Genome-wide mapping found that BEAF usually binds near transcription start sites, often of housekeeping genes, suggesting a role in promoter function. This would be a nontraditional role for an insulator-binding protein. To gain insight into molecular mechanisms of BEAF function, we identified interacting proteins using yeast two-hybrid assays. Here, we focus on the transcription factor Serendipity (Sry-). Interactions were confirmed in pull-down experiments using bacterially expressed proteins, by bimolecular fluorescence complementation, and in a genetic assay in transgenic flies. Sry- interacted with promoter-proximal BEAF both when bound to DNA adjacent to BEAF or > 2-kb upstream to activate a reporter gene in transient transfection experiments. The interaction between BEAF and Sry- was detected using both a minimal developmental promoter (y) and a housekeeping promoter (RpS12), while BEAF alone strongly activated the housekeeping promoter. These two functions for BEAF implicate it in playing a direct role in gene regulation at hundreds of BEAF-associated promoters.

Key Points

A Yersinia pestis mutant synthesizing an adjuvant form of lipid A (monophosphoryl lipid A, MPLA) displayed increased biogenesis of bacterial outer membrane vesicles (OMVs). To enhance the immunogenicity of the OMVs, we constructed an Asd-based balanced-lethal host-vector system that oversynthesized the LcrV antigen of Y. pestis, raised the amounts of LcrV enclosed in OMVs by the type II secretion system, and eliminated harmful factors like plasminogen activator (Pla) and murine toxin from the OMVs. Vaccination with OMVs containing MPLA and increased amounts of LcrV with diminished toxicity afforded complete protection in mice against subcutaneous challenge with 8 x 10⁵ CFU (80,000 50% lethal dose [LD₅₀]) and intranasal challenge with 5 x 10³ CFU (50 LD₅₀) of virulent Y. pestis. This protection was significantly superior to that resulting from vaccination with LcrV/alhydrogel or rF1-V/alhydrogel. At week 4 postimmunization, the OMV-immunized mice showed more robust titers of antibodies against LcrV, Y. pestis whole-cell lysate (YPL), and F1 antigen and more balanced IgG1:IgG2a/IgG2b-derived Th1 and Th2 responses than LcrV-immunized mice. Moreover, potent adaptive and innate immune responses were stimulated in the OMV-immunized mice. Our findings demonstrate that self-adjuvanting Y. pestis OMVs provide a novel plague vaccine candidate and that the rational design of OMVs could serve as a robust approach for vaccine development.

Human adenoviruses have many attractive features for gene therapy applications. However, the high prevalence of preexisting immunity against these viruses in general populations worldwide has greatly limited their clinical utility. In addition, the most commonly used human adenovirus, human adenovirus subgroup C serotype 5 (HAd5), when systemically administered, triggers systemic inflammation and toxicity, with the liver being the most severely affected organ. Here, we evaluated the utility and safety of a new low-seroprevalence gorilla adenovirus (GAd; GC46) as a gene transfer vector in mice. Biodistribution studies revealed that systemically administered GAd had a selective and robust lung endothelial cell (EC) tropism with minimal vector expression throughout many other organs and tissues. Administration of a high dose of GAd accomplished extensive transgene expression in the lung yet elicited no detectable inflammatory histopathology in this organ. Furthermore, GAd, unlike HAd5, did not exhibit hepatotropism or induce liver inflammatory toxicity in mice, demonstrating the exceptional safety profile of the vector vis-à-vis systemic utility. We further demonstrated that the GAd capsid fiber shared the flexibility of the HAd5 equivalent for permitting genetic modification; GAd with the pan-EC-targeting ligand myeloid cell-binding peptide (MBP) incorporated in the capsid displayed a reduced lung tropism and efficiently retargeted gene expression to vascular beds in other organs.

IMPORTANCE In the aggregate, our mouse studies suggest that GAd is a promising gene therapy vector that utilizes lung ECs as a source of therapeutic payload production and a highly desirable toxicity profile. Further genetic engineering of the GAd capsid holds the promise of in vivo vector tropism modification and targeting.

The ocean is our planet’s largest life-support system. It stabilizes climate; stores carbon; produces oxygen; nurtures biodiversity; directly supports human well-being through food, mineral, and energy resources; and provides cultural and recreational services. The value of the ocean economy speaks to its importance: The Organization for Economic Cooperation and Development...

Tree structures, showing hierarchical relationships and the latent structures between samples, are ubiquitous in genomic and biomedical sciences. A common question in many studies is whether there is an association between a response variable measured on each sample and the latent group structure represented by some given tree. Currently, this...

Sleep pressure and sleep depth are key regulators of wake and sleep. Current methods of measuring these parameters in Drosophila melanogaster have low temporal resolution and/or require disrupting sleep. Here we report analysis tools for high-resolution, noninvasive measurement of sleep pressure and depth from movement data. Probability of initiating activity,...

Actuation remains a significant challenge in soft robotics. Actuation by light has important advantages: Objects can be actuated from a distance, distinct frequencies can be used to actuate and control distinct modes with minimal interference, and significant power can be transmitted over long distances through corrosion-free, lightweight fiber optic cables....

Isoprene has the highest emission into Earth’s atmosphere of any nonmethane hydrocarbon. Atmospheric processing of alkenes, including isoprene, via ozonolysis leads to the formation of zwitterionic reactive intermediates, known as Criegee intermediates (CIs). Direct studies have revealed that reactions involving simple CIs can significantly impact the tropospheric oxidizing capacity, enhance...

Toward the goal of increasing the throughput of high-resolution mass characterization of intact antibodies, we developed a RapidFire–mass spectrometry (MS) assay using electrospray ionization. We achieved unprecedented screening throughput as fast as 15 s/sample, which is an order of magnitude improvement over conventional liquid chromatography (LC)-MS approaches. The screening enabled...

Does infant temperament predict adult personality and life-course patterns? To date, there is scant evidence examining relations between child temperament and adult outcomes, and extant research has relied on limited methods for measuring temperament such as maternal report. This prospective longitudinal study followed a cohort of infants (n = 165)...

At the pinnacle of the 17th century scientific revolution, René Descartes, the father of modern philosophy, published his monumental Meditations on First Philosophy (1), in which he proposed a division between soul and body—mind and brain—with the former in charge of our thoughts and conscious decisions (res cogitans) and the...

Conserving biodiverse habitats Contextual habitat intactness for biodiversity. Dark shades indicate high intactness, and colors indicate levels of human influence (Blue = wilderness, Green = low disturbance, Orange = modified, Pink = highly modified). Natural habitat loss contributes to biodiversity loss, and by some estimates nearly half a million species...

This article is meant as a personal reflection on my unexpected retirement, and includes memories and thoughts about my career with the Indian Health Service near the border with Mexico, serving the Tohono O’odham tribe.

There are approximately 1 million transgender and gender-diverse adults in the United States. Despite increased awareness and acceptance, they frequently encounter medical settings that are not welcoming and/or health care providers who are not knowledgeable about their health needs. Use of correct terminology, following best practices for name and pronoun use, and knowledge of gender-affirming interventions can create office environments that are welcoming to transgender clients. Health disparities faced by transgender patients that impact access to care include higher rates of mental health issues, substance use disorders, violence, and poverty. Transgender women are at greater risk for HIV acquisition and are less likely to achieve viral suppression compared with cisgender (nontransgender) individuals. Medical providers can facilitate HIV prevention efforts by offering pre- and postexposure prophylaxis to transgender patients at risk for HIV infection. Improving health outcomes requires attention to cultural competency and an understanding of lived experiences and priorities of transgender people.

Purpose:

Clinical evidence shows minimal benefit to vitamin D screening and subsequent treatment in the general population. This study aims to assess the effectiveness of 2 light-touch interventions on reducing vitamin D test orders.

Fredrik Andreasson, Arne Hegemann, Andreas Nord, and Jan-Ake Nilsson

The capacity to get rid of excess heat produced during hard work is a possible constraint on parental effort during reproduction [heat dissipation limit (HDL) theory]. We released hard-working blue tits (Cyanistes caeruleus) from this constraint by experimentally removing ventral plumage. We then assessed whether this changed their reproductive effort (feeding rate and nestling size) and levels of self-maintenance (change in body mass and innate immune function). Feather-clipped females reduced the number of feeding visits and increased levels of constitutive innate immunity compared with unclipped females but did not fledge smaller nestlings. Thus, they increased self-maintenance without compromising current reproductive output. In contrast, feather clipping did not affect the number of feeding visits or innate immune function in males, despite increased heat loss rate. Our results show that analyses of physiological parameters, such as constitutive innate immune function, can be important when trying to understand sources of variation in investment in self-maintenance versus reproductive effort and that risk of overheating can influence innate immune function during reproduction.

Irene Verhagen, Barbara M. Tomotani, Phillip Gienapp, and Marcel E. Visser

Phenotypic plasticity is an important mechanism by which an individual can adapt its seasonal timing to predictable, short-term environmental changes by using predictive cues. Identification of these cues is crucial to forecast the response of species to long-term environmental change and to study their potential to adapt. Individual great tits (Parus major) start reproduction early under warmer conditions in the wild, but whether this effect is causal is not well known. We housed 36 pairs of great tits in climate-controlled aviaries and 40 pairs in outdoor aviaries, where they bred under artificial contrasting temperature treatments or in semi-natural conditions, respectively, for two consecutive years, using birds from lines selected for early and late egg laying. We thus obtained laying dates in two different thermal environments for each female. Females bred earlier under warmer conditions in climate-controlled aviaries, but not in outdoor aviaries. The latter was inconsistent with laying dates from our wild population. Further, early selection line females initiated egg laying consistently ~9 days earlier than late selection line females in outdoor aviaries, but we found no difference in the degree of plasticity (i.e. the sensitivity to temperature) in laying date between selection lines. Because we found that temperature causally affects laying date, climate change will lead to earlier laying. This advancement is, however, unlikely to be sufficient, thereby leading to selection for earlier laying. Our results suggest that natural selection may lead to a change in mean phenotype, but not to a change in the sensitivity of laying dates to temperature.

Surendra Singh Patel, Sanyami Zunjarrao, and Beena Pillai

Eisenia fetida, the common vermicomposting earthworm, shows robust regeneration of posterior segments removed by amputation. During the period of regeneration, the newly formed tissue initially contains only undifferentiated cells but subsequently differentiates into a variety of cell types including muscle, nerve and vasculature. Transcriptomics analysis, reported previously, provided a number of candidate non-coding RNAs that were induced during regeneration. We found that one such long non-coding RNA (lncRNA) is expressed in the skin, only at the base of newly formed chaetae. The spatial organization and precise arrangement of the regenerating chaetae and the cells expressing the lncRNA on the ventral side clearly support a model wherein the regenerating tissue contains a zone of growth and cell division at the tip and a zone of differentiation at the site of amputation. The temporal expression pattern of the lncRNA, named Neev, closely resembled the pattern of chitin synthase genes, implicated in chaetae formation. We found that the lncRNA has 49 sites for binding a set of four microRNAs (miRNAs) while the chitin synthase 8 mRNA has 478 sites. The over-representation of shared miRNA sites suggests that lncRNA Neev may act as a miRNA sponge to transiently de-repress chitin synthase 8 during formation of new chaetae in the regenerating segments of Eisenia fetida.

Vanessa Corby-Harris, Megan E. Deeter, Lucy Snyder, Charlotte Meador, Ashley C. Welchert, Amelia Hoffman, and Bethany T. Obernesser

Recent widespread honey bee (Apis mellifera) colony loss is attributed to a variety of stressors, including parasites, pathogens, pesticides and poor nutrition. In principle, we can reduce stress-induced declines in colony health by either removing the stressor or increasing the bees' tolerance to the stressor. This latter option requires a better understanding than we currently have of how honey bees respond to stress. Here, we investigated how octopamine, a stress-induced hormone that mediates invertebrate physiology and behavior, influences the health of young nurse-aged bees. Specifically, we asked whether octopamine induces abdominal lipid and hypopharyngeal gland (HG) degradation, two physiological traits of stressed nurse bees. Nurse-aged workers were treated topically with octopamine and their abdominal lipid content, HG size and HG autophagic gene expression were measured. Hemolymph lipid titer was measured to determine whether tissue degradation was associated with the release of nutrients from these tissues into the hemolymph. The HGs of octopamine-treated bees were smaller than control bees and had higher levels of HG autophagy gene expression. Octopamine-treated bees also had higher levels of hemolymph lipid compared with control bees. Abdominal lipids did not change in response to octopamine. Our findings support the hypothesis that the HGs are a rich source of stored energy that can be mobilized during periods of stress.

Karen L. Carleton, Daniel Escobar-Camacho, Sara M. Stieb, Fabio Cortesi, and N. Justin Marshall

Among vertebrates, teleost eye diversity exceeds that found in all other groups. Their spectral sensitivities range from ultraviolet to red, and the number of visual pigments varies from 1 to over 40. This variation is correlated with the different ecologies and life histories of fish species, including their variable aquatic habitats: murky lakes, clear oceans, deep seas and turbulent rivers. These ecotopes often change with the season, but fish may also migrate between ecotopes diurnally, seasonally or ontogenetically. To survive in these variable light habitats, fish visual systems have evolved a suite of mechanisms that modulate spectral sensitivities on a range of timescales. These mechanisms include: (1) optical media that filter light, (2) variations in photoreceptor type and size to vary absorbance and sensitivity, and (3) changes in photoreceptor visual pigments to optimize peak sensitivity. The visual pigment changes can result from changes in chromophore or changes to the opsin. Opsin variation results from changes in opsin sequence, opsin expression or co-expression, and opsin gene duplications and losses. Here, we review visual diversity in a number of teleost groups where the structural and molecular mechanisms underlying their spectral sensitivities have been relatively well determined. Although we document considerable variability, this alone does not imply functional difference per se. We therefore highlight the need for more studies that examine species with known sensitivity differences, emphasizing behavioral experiments to test whether such differences actually matter in the execution of visual tasks that are relevant to the fish.

Krishnamoorthy Krishnan, Asif Shahriar Nafi, Roi Gurka, and Roi Holzman

Fish larvae are the smallest self-sustaining vertebrates. As such, they face multiple challenges that stem from their minute size, and from the hydrodynamic regime in which they dwell. This regime, of intermediate Reynolds numbers, was shown to affect the swimming of larval fish and impede their ability to capture prey. Prey capture is impeded because smaller larvae produce weaker suction flows, exerting weaker forces on the prey. Previous observations on feeding larvae also showed prey exiting the mouth after initially entering it (hereafter "in-and-out"), although the mechanism causing such failures had been unclear. In this study, we used numerical simulations to investigate the hydrodynamic mechanisms responsible for the failure to feed caused by this in-and-out prey movement. Detailed kinematics of the expanding mouth during prey capture by larval Sparus aurata were used to parameterize age-specific numerical models of the flows inside the mouth. These models revealed that for small larvae which expand their mouth slowly, fluid entering the mouth cavity is expelled through the mouth before it is closed, resulting in flow reversal at the orifice. This relative efflux of water through the mouth was >8% of the influx through the mouth for younger ages. However similar effluxes were found when we simulated slow strikes by larger fish. The simulations can explain the observations of larval fish failing to fish due to the in-and-out movement of the prey. These results further highlight the importance of transporting the prey from the gape deeper into the mouth cavity in determining suction-feeding success.

Imants G. Priede, Rhoderick W. Burgass, Manolis Mandalakis, Apostolos Spyros, Petros Gikas, Finlay Burns, and Jim Drewery

Whereas upper ocean pelagic sharks are negatively buoyant and must swim continuously to generate lift from their fins, deep-sea sharks float or swim slowly buoyed up by large volumes of low-density oils in their livers. Investigation of the Pressure, Volume, Temperature (PVT) relationships for liver oils of 10 species of deep-sea Chondrichthyes shows that the density difference between oil and seawater, remains almost constant with pressure down to full ocean depth (11 km, 1100 bar); theoretically providing buoyancy far beyond the maximum depth of occurrence (3700 m) of sharks. However, , does change significantly with temperature and we show that the combined effects of pressure and temperature can decrease buoyancy of oil by up to 10% between the surface and 3500 m depth across interfaces between warm southern and cold polar waters in the Rockall Trough in the NE Atlantic. This increases drag more than 10 fold compared with neutral buoyancy during horizontal slow swimming (0.1 m s^–1) but the effect becomes negligible at high speeds. Chondrichthyes generally experience positive buoyancy change during ascent and negative buoyancy change during descent but contrary effects can occur at interfaces between waters of different densities. During normal vertical migrations buoyancy changes are small, increasing slow-speed drag by no more than 2–3 fold. Equations and tables of density, pressure and temperature are provided for squalene and liver oils of Chimaeriformes (Harriotta raleighana, Chimaera monstrosa, Chimaera monstrosa), Squaliformes (Centrophorus squamosus, Deania calcea, Centroscymnus coelolepis, Centroscyllium fabricii, Etmopterus spinax) and Carcharhiniformes (Apristurus laurussonii, Galeus murinus).

Daniel J. Tobiansky, Meredith C. Miles, Franz Goller, and Matthew J. Fuxjager

Performance trade-offs can dramatically alter an organism's evolutionary trajectory by making certain phenotypic outcomes unattainable. Understanding how these trade-offs arise from an animal's design is therefore an important goal of biology. To explore this topic, we study how androgenic hormones, which regulate skeletal muscle function, influence performance trade-offs relevant to different components of complex reproductive behaviour. We conduct this work in golden-collared manakins (Manacus vitellinus), a Neotropical bird in which males court females by rapidly snapping their wings together above their back. Androgens help mediate the snap displays by radically increasing the twitch speed of a dorsal wing muscle [scapulohumeralis caudalis (SH)], which actuates the bird's wing-snap. Through hormone manipulations and in situ muscle recordings, we test how these positive effects on SH speed influence trade-offs with endurance. Indeed, this trait impacts the display by shaping signal length. We find that androgen-dependent increases in SH speed incur a cost to endurance, particularly when this muscle performs at its functional limits. Moreover, when behavioural data are overlaid on our muscle recordings, displaying animals appear to balance display speed with fatigue-induced muscle fusion (physiological tetanus) to generate the fastest possible signal while maintaining an appropriate signal duration. Our results point to androgenic hormone action as a functional trigger of trade-offs in sexual performance—they enhance one element of a courtship display, but in doing so, impede another.

Andre J. Riveros, Anne S. Leonard, Wulfila Gronenberg, and Daniel R. Papaj

Similar to animal communication displays, flowers emit complex signals that attract pollinators. Signal complexity could lead to higher cognitive load, impairing performance, or might benefit pollinators by facilitating learning, memory and decision-making. Here, we evaluate learning and memory in foragers of the bumble bee Bombus impatiens trained to simple (unimodal) vs. complex signals (bimodal) under restrained conditions. Use of a proboscis extension response protocol enabled us to control the timing and duration of stimuli presented during absolute and differential learning tasks. Overall, we observed broad variation in the performance under the two conditions, with bees trained to compound bimodal signals learning and remembering as well as, better, or more poorly than bees trained to unimodal signals. Interestingly, the outcome of training was affected by the specific colour-odour combination. Among unimodal stimuli, the performance with odour stimuli was higher than with colour stimuli, suggesting that olfactory signals played a more significant role in the compound bimodal condition. This was supported by the fact that after 24 h, most bimodal-treatment bees responded to odour but not visual stimuli. We did not observe differences in latency of response, suggesting that signal composition affected decision accuracy, not speed. We conclude that restrained bumble bee workers exhibit broad variation of responses to bimodal stimuli and that components of the bimodal signal may not be used equivalently. The analysis of bee performance under restrained conditions enables accurately control the multimodal stimuli provided to individuals and to study the interaction of individual components within a compound.