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Sociality is widespread among animals, and involves complex relationships within and between social groups. While intragroup interactions are often cooperative, intergroup interactions typically involve conflict, or at best tolerance. Active cooperation between members of distinct, separate groups occurs very rarely, predominantly in some primate and ant species. Here, we ask why intergroup cooperation is so rare, and what conditions favour its evolution. We present a model incorporating intra- and intergroup relationships and local and long-distance dispersal. We show that dispersal modes play a pivotal role in the evolution of intergroup interactions. Both long-distance and local dispersal processes drive population social structure, and the costs and benefits of intergroup conflict, tolerance and cooperation. Overall, the evolution of multi-group interaction patterns, including both intergroup aggression and intergroup tolerance, or even altruism, is more likely with mostly localized dispersal. However, the evolution of these intergroup relationships may have significant ecological impacts, and this feedback may alter the ecological conditions that favour its own evolution. These results show that the evolution of intergroup cooperation is favoured by a specific set of conditions, and may not be evolutionarily stable. We discuss how our results relate to empirical evidence of intergroup cooperation in ants and primates. This article is part of a discussion meeting issue ‘Collective behaviour through time’.

Background Factors known to be associated with outcome of acquired myasthenia gravis (MG) in dogs are limited. Hypothesis/Objectives Of dogs with MG, advancing age and comorbid neoplasia are associated with poor long‐term prognosis and low rates of remission. Animals Ninety‐four client‐owned dogs with MG diagnosed by acetylcholine receptor antibody (AChR Ab) assay between 2001 and 2019 from a university clinic and 3 private clinics in the United States. Methods Cases were retrospectively evaluated and data were collected to determine clinical signs, treatment, and response to therapy defined by means of a clinical scoring rubric. Immunological remission was defined as a return of the AChR Ab concentration to

Performing a dramatic act of religious devotion, creating an art exhibit, or releasing a new product are all examples of public acts that signal quality and contribute to building a reputation. Signalling theory predicts that these public displays can reliably reveal quality. However, data from ethnographic work in South India suggests that more prominent individuals gain more from reputation-building religious acts than more marginalized individuals. To understand this phenomenon, we extend signalling theory to include variation in people’s social prominence or social capital, first with an analytical model and then with an agent-based model. We consider two ways in which social prominence/capital may alter signalling: (i) it impacts observers’ priors, and (ii) it alters the signallers’ pay-offs. These two mechanisms can result in both a ‘reputational shield,’ where low quality individuals are able to ‘pass’ as high quality thanks to their greater social prominence/capital, and a ‘reputational poverty trap,’ where high quality individuals are unable to improve their standing owing to a lack of social prominence/capital. These findings bridge the signalling theory tradition prominent in behavioural ecology, anthropology and economics with the work on status hierarchies in sociology, and shed light on the complex ways in which individuals make inferences about others. This article is part of the theme issue ‘The language of cooperation: reputation and honest signalling’.

Exercise Satiation is a novel theoretical conceptualization for problematic exercise often observed in eating disorders. Problematic exercise is present across the spectrum of eating disorder presentations and is a cardinal symptom of eating disorders that has been difficult to treat historically. Conceptualizing exercise in the context of Reward Satiation similar to other biological drives such as eating could provide new insights into the etiology, maintenance, and treatment of problematic exercise in eating disorders. Through this understanding, we may be able to provide and increase adherence to interventions that target these mechanisms and as such, reduce impairment associated with problematic exercise for those with eating disorders. Using the Research Domain Criteria (RDoC) framework, we propose and discuss potential research avenues to explore Exercise Satiation in the context of eating disorders.

Humans frequently perform extravagant and seemingly costly behaviors, such as widely sharing hunted resources, erecting conspicuous monumental structures, and performing dramatic acts of religious devotion. Evolutionary anthropologists and archeologists have used signaling theory to explain the function of such displays, drawing inspiration from behavioral ecology, economics, and the social sciences. While signaling theory is broadly aimed at explaining honest communication, it has come to be strongly associated with the handicap principle, which proposes that such costly extravagance is in fact an adaptation for signal reliability. Most empirical studies of signaling theory have focused on obviously costly acts, and consequently anthropologists have likely overlooked a wide range of signals that also promote reliable communication. Here, we build on recent developments in signaling theory and animal communication, developing an updated framework that highlights the diversity of signal contents, costs, contexts, and reliability mechanisms present within human signaling systems. By broadening the perspective of signaling theory in human systems, we strive to identify promising areas for further empirical and theoretical work. peerReviewed

Protecting the environment is a social dilemma: environmental protection benefits everyone but is individually costly. We propose that protecting the environment is similar to other types of cooperation, in that environmentalism functions as a signal of one’s willingness to cooperate with others. We test several novel predictions from this hypothesis. We used a mathematical model to show that environmentalism can indicate one’s valuation of others and thus one’s cooperative intent. We found support for this prediction in two online studies, and then conducted two laboratory studies to extend the idea that environmentalism signals one’s willingness to cooperate. Participants donated more to an environmental charity when donations were public than when anonymous, but they donated the most when competing to be chosen by an observer for a subsequent cooperative game. In other words, people competed to donate more to the environment. Bigger donors benefited, as they were subsequently chosen more often and received more cooperation from their partners. Partners benefited from choosing environmental donors: bigger donors cooperated more with subsequent partners, such that environmental donations were reliably informative about participants’ future cooperativeness. We compare multiple theories about why people behave environmentally (indirect reciprocity, signal of wealth, signal of cooperative intent), and find most support for our proposed theory of signaling cooperative intent. By understanding the function of environmental behaviour and stimulating competitive giving, we can increase people’s support for environmental and other charitable causes.

How do animals forage for variable food resources? For animals foraging at flowers, floral constancy has provided a framework for understanding why organisms visit some flowers while bypassing others. We extend this framework to the flower-handling tactics that visitors employ. Nectar robbers remove nectar through holes bitten in flowers, often without pollinating. Many foragers can switch between robbing and visiting flowers legitimately to gain access to nectar. We document that even though individuals can switch foraging tactics, they often do not. We explore whether individuals exhibit constancy to either robbing or visiting legitimately, which we term tactic constancy. We then extend hypotheses of floral constancy to understand when and why visitors exhibit tactic constancy and raise questions for future research.

Aquifer storage, transfer and recovery (ASTR) may be an efficient low cost water supply technology for rural coastal communities that experience seasonal freshwater scarcity. The feasibility of ASTR as a water supply alternative is being evaluated in communities in south-western Bangladesh where the shallow aquifers are naturally brackish and severe seasonal freshwater scarcity is compounded by frequent extreme weather events. A numerical variable-density groundwater model, first evaluated against data from an existing community-scale ASTR system, was applied to identify the influence of hydrogeological as well as design and operational parameters on system performance. For community-scale systems, it is a delicate balance to achieve acceptable water quality at the extraction well whilst maintaining a high recovery efficiency (RE) as dispersive mixing can dominate relative to the small size of the injected freshwater plume. For the existing ASTR system configuration used in Bangladesh where the injection head is controlled and the extraction rate is set based on the community water demand, larger aquifer hydraulic conductivity, aquifer depth and injection head improve the water quality (lower total dissolved solids concentration) in the extracted water because of higher injection rates, but the RE is reduced. To support future ASTR system design in similar coastal settings, an improved system configuration was determined and relevant non-dimensional design criteria were identified. Analyses showed that four injection wells distributed around a central single extraction well leads to high RE provided the distance between the injection wells and extraction well is less than half the theoretical radius of the injected freshwater plume. The theoretical plume radius relative to the aquifer dispersivity is also an important design consideration to ensure adequate system performance. The results presented provide valuable insights into the feasibility and design considerations for community-scale ASTR systems but installation of systems in different hydrogeological contexts (i.e. high regional hydraulic gradient and aquifer TDS concentration) may require re-evaluation of the system design.

Why should organisms incur a cost in order to inflict a (usually greater) cost on others? Such costly harming behavior may be favored when competition for resources occurs locally, because it increases individuals' fitness relative to close competitors. However, there is no explicit experimental evidence supporting the prediction that people are more willing to harm others under local versus global competition. We illustrate this prediction with a game theoretic model, and then test it in a series of economic games. In these experiments, players could spend money to make others lose more. We manipulated the scale of competition by awarding cash prizes to the players with the highest payoffs per set of social partners (local competition) or in all the participants in a session (global competition). We found that, as predicted, people were more harmful to others when competition was local (Study 1). This result still held when people "earned" (rather than were simply given) their money (Study 2). In addition, when competition was local, people were more willing to harm ingroup members than outgroup members (Study 3), because ingroup members were the relevant competitive targets. Together, our results suggest that local competition in human groups not only promotes willingness to harm others in general, but also causes ingroup hostility.

Floral communities present complex and shifting resource landscapes for flower-foraging animals. Strong similarities among the floral displays of different plant species, paired with high variability in reward distributions across time and space, can weaken correlations between floral signals and reward status. As a result, it should be difficult for foragers to discriminate between rewarding and rewardless flowers. Building on signal detection theory in behavioural ecology, we use hypothetical probability density functions to examine graphically how plant signals pose challenges to forager decision-making. We argue that foraging costs associated with incorrect acceptance of rewardless flowers and incorrect rejection of rewarding ones interact with community-level reward availability to determine the extent to which rewardless and rewarding species should overlap in flowering time. We discuss the evolutionary consequences of these phenomena from both the forager and the plant perspectives.This article is part of the theme issue ‘Signal detection theory in recognition systems: from evolving models to experimental tests’.

Introduction:hypertension is a longstanding problem in Zambia, yet little is known about its prevalence and risk factors, particularly in rural and urban settings. Identifying geographical variations in hypertension is important to enhance the health of adult Zambians regardless of where they live. Therefore, the purpose of this study was to compare the prevalence of hypertension and related risk factors between rural (n = 130) and urban (n = 131) communities in Western Province, Zambia. Methods:this cross-sectional study included urban and rural adult Zambians attending health checks who completed a modified World Health Organization (WHO) survey, and had blood pressure and anthropometric measurements completed. Descriptive statistics were used to summarize demographic and risk factor variables. Chi-square tests of association were used to analyze relationships between categorical variables, t-tests to analyze relationships between continuous variables and logistic regression to examine associations of hypertension with selected risk factors. Results:the prevalence of hypertension in rural Zambians was double (46.9%) that of urban Zambians (22.9%). Increasing age, not engaging in walking/biking, and alcohol intake within the last 30 days were associated with an increased likelihood of hypertension in rural Zambians while eating vegetables more days during the week was associated with a decreased likelihood of hypertension in rural Zambians. Body Mass Index (BMI) was significantly associated with an increased likelihood of hypertension in urban Zambians. Conclusion:modifiable risk factors (such as BMI, dietary intake, and physical activity) are associated with hypertension prevalence in this population, indicating opportunities for screening and other prevention measures.

How do nectar-feeding animals choose among alternative flower-handling tactics? Such decisions have consequences not only for animal fitness (via food intake) but for plant fitness as well: many animals can choose to “rob” nectar through holes chewed in the base of a flower instead of “legitimately” collecting it through the flower’s opening, thus failing to contact pollen. Although variation within a species in these nectar-foraging tactics is well documented, it is largely unknown why some individuals specialize (at least in the short term) on robbing, others on legitimate visitation, and others switch between these behaviors. We investigated whether the tendency to rob nectar through previously-made holes (secondary robbing) is influenced by prior foraging experience. In a laboratory experiment, we trained groups of bumble bees (Bombus impatiens) either to visit artificial flowers legitimately or to secondary-rob; a third group received no training. On subsequent visits to flowers, all bees had the opportunity to use either foraging tactic. We found that experience did affect bees’ tendency to secondary-rob: trained bees were more likely to adopt the tactic they had previously experienced. Untrained bees initially sampled both tactics, but over time preferred to secondary-rob. Experience also increased bees’ success at gaining nectar from flowers, but only when visiting flowers legitimately (the less preferred tactic). Overall, these findings highlight the importance of experience in animals’ choices of alternative handling tactics while foraging and help explain long-standing observations of variation in nectar-robbing behavior among individuals of the same population. Animals that can adopt alternative behaviors frequently use only one of them. A widespread but little understood example of this is nectar feeding, in which foragers can choose between “legitimately” collecting nectar through a flower’s opening or “robbing” nectar via holes chewed through a flower’s base. We showed in a laboratory experiment that prior foraging experience can bias bumble bees’ choices to rob nectar from pre-existing holes (i.e., to “secondary”-rob). Initial exposure to flowers that could only be robbed or only be legitimately visited increased bees’ tendency to subsequently adopt that behavior at the expense of sampling the alternative behavior, even when other bees seemed to prefer the alternative. These results help explain field observations that bees often specialize on a single nectar-collecting behavior and that there is individual variation in which behavior is adopted, contributing to our understanding of nectar robbing from the animals’ perspective.

Social animals vary in their ability to compete with group members over shared resources and also vary in their cooperative efforts to produce these resources. Competition among groups can promote within‐group cooperation, but many existing models of intergroup cooperation do not explicitly account for observations that group members invest differentially in cooperation and that there are often within‐group competitive or power asymmetries. We present a game theoretic model of intergroup competition that investigates how such asymmetries affect within‐group cooperation. In this model, group members adopt one of two roles, with relative competitive efficiency and the number of individuals varying between roles. Players in each role make simultaneous, coevolving decisions. The model predicts that although intergroup competition increases cooperative contributions to group resources by both roles, contributions are predominantly from individuals in the less competitively efficient role, whereas individuals in the more competitively efficient role generally gain the larger share of these resources. When asymmetry in relative competitive efficiency is greater, a group's per capita cooperation (averaged across both roles) is higher, due to increased cooperation from the competitively inferior individuals. For extreme asymmetry in relative competitive efficiency, per capita cooperation is highest in groups with a single competitively superior individual and many competitively inferior individuals, because the latter acquiesce and invest in cooperation rather than within‐group competition. These predictions are consistent with observed features of many societies, such as monogynous Hymenoptera with many workers and caste dimorphism.

Social interactions are often characterized by cooperation within groups andconflict or competition between groups. In certain circumstances, however,cooperation can arise between social groups. Here, we examine the circumstances under which inter-group cooperation is expected to emerge andpresent examples with particular focus on groups in two well-studied butdissimilar taxa: humans and ants. Drivers for the evolution of inter-groupcooperation include overarching threats frompredators, competitors or adverseconditions, and group-level resource asymmetries. Resources can differbetween groups in both quantity and type. Where the difference is in type,inequalities can lead to specialization and division of labour between groups,a phenomenon characteristic of human societies, but rarely seen in other animals. The ability to identify members of one’s own group is essential forsocial coherence; we consider the proximate roles of identity effects in shapinginter-group cooperation and allowing membership of multiple groups. Finally,we identify numerous valuable avenues for future research that will improveour understanding of the processes shaping inter-group cooperation.

BACKGROUND: The prevalence of atrial fibrillation (AF) is increasing in sub-Saharan Africa and contributes to significant morbidity and mortality from stroke and other cardiovascular diseases. Case finding in some areas of the country, such as in rural Zambia is especially challenging with limited availability of ambulatory electrocardiogram monitoring devices. Moreover, there is very little qualitative research exploring Zambian patients’ experiences living with AF. AIMS: The two-fold purpose of this study was i) to explore the use of a screening tool for detecting AF in Western Province, Zambia and ii) to understand the patient experience of living with AF. SETTING: Mongu and Limulunga Districts in the Western Province of Zambia. METHODS: Mixed methods. Convenience sampling for both quantitative and qualitative arms of the study was used to recruit participants attending public ‘Health Checks.’ Quantitative data were collected by means of an interview-administered survey and qualitative data were obtained through individual interviews. RESULTS: An irregular manual pulse was found in 12.6% (n=33) of Zambians who attended the Health Checks and two participants were confirmed to have AF. Zambians with an irregular pulse had a significantly higher prevalence of hypertension and were significantly less sedentary than those without pulse irregularities. Two themes emerged from the interview with two patients diagnosed with AF: symptoms and healthcare access. CONCLUSION: Hypertension continues to be a problem in adult Zambians and is an independent risk factor for stroke and, when diagnosed in conjunction with AF, further compounds stroke risk. Access to screening and diagnostic care for AF is essential, especially in currently underserved rural areas. In addition, participants presented with unique risk factors, such as consolidated periods of exercise, that require further research to determine context and seasonal variation so as to improve education and prevention strategies.

Qiagen's Investigator™ Quantiplex kit, a total human DNA quantitation kit, has a 200-base pair internal control, fast cycling time, and scorpion molecules containing a covalently linked primer, probe, fluorophore, and quencher. The Investigator™ Quantiplex kit was evaluated to investigate a value under which complete short tandem repeat (STR) failure was consistently obtained. Buccal swabs were extracted using the Qiagen QIAamp(®) DNA Blood Mini Kit, quantified with the Investigator™ Quantiplex kit using a tested half-volume reaction, amplified with the ABI AmpFlSTR(®) Identifiler kit, separated on the 3100Avant Genetic Analyzer, and data analyzed with GeneMapper(®) ID v.3.2. While undetected samples were unlikely to produce sufficient data for statistical calculations or CODIS upload (2.00 alleles and 0.82 complete loci on average), data may be useful for exclusionary purposes. Thus, the Investigator™ Quantiplex kit may be useful for predicting STR success. These findings are comparable with previously reported data from the Quantifiler™ Human kit.

Cooperation is widespread both within and between species, but are intra-specific and inter-specific cooperation fundamentally similar or qualitatively different phenomena? This review evaluates this question, necessary for a general understanding of the evolution of cooperation. First, we outline three advantages of cooperation relative to non-cooperation (acquisition of otherwise inaccessible goods and services, more efficient acquisition of resources, and buffering against variability), and predict when individuals should cooperate with a conspecific versus a heterospecific partner to obtain these advantages. Second, we highlight five axes along which heterospecific and conspecific partners may differ: relatedness and fitness feedbacks, competition and resource use, resource-generation abilities, relative evolutionary rates, and asymmetric strategy sets and outside options. Along all of these axes, certain asymmetries between partners are more common in, but not exclusive to, cooperation between species, especially complementary resource use and production. We conclude that cooperation within and between species share many fundamental qualities, and that differences between the two systems are explained by the various asymmetries between partners. Consideration of the parallels between intra- and inter-specific cooperation facilitates application of well-studied topics in one system to the other, such as direct benefits within species and kin-selected cooperation between species, generating promising directions for future research.

Objective To evaluate efficacy of a topical epidural analgesia used alone, or in combination with hydromorphone, against a standard pain protocol for the 48 hours immediately after hemilaminectomy. Study Design Randomized, blinded, controlled, clinical trial. Animals Dogs (n = 30) with thoracolumbar intervertebral disc disease treated with hemilaminectomy. Methods Dogs were randomly divided into 3 groups: group 1 received intermittent hydromorphone postoperatively, group 2 received a topical epidural of preservative-free morphine and dexmedetomidine administered via gel foam, group 3 received both forms of analgesia. All dogs were monitored and assessed for pain for 48 hours immediately postoperatively. Data were analyzed using MANOVA and Wilcoxon Rank Sum Tests. Results There was a significant temporal difference in treatment groups 1 and 3 when using a 0–10 pain scale (MANOVA, P = .02). There was also a significant difference at the 48th hour postoperatively between groups 1 and 3 (Wilcoxon Rank Sum Test). Conclusion Topical epidural of preservative-free morphine and dexmedetomidine administered via gelfoam is not sufficient analgesia alone post hemilaminectomy but in conjunction with other opioid administration may lead to superior pain relief.

Social organisms in many taxa cooperate to produce resources that are shared among group members. Some cooperatively produced resources may be monopolized by individuals who invest in within-group competition, but these have largely been overlooked in empirical and theoretical research on human cooperation, which has focused on noncontestable public goods. In this study, we allow for the potential of within-group competition over cooperatively produced resources and use a game theoretic "tug-of-war" model and empirical test to show that such competition decreases the degree of cooperation within human groups and hence decreases group members' payoffs. Our study thus sheds light on how cooperative production and equal division of shared resources may have evolved, expands on current models of human cooperation to reflect the many natural conditions with opportunities for within-group competition, and demonstrates unifying principles in cooperation and competition across the animal kingdom.

The objective of this research is to measure and characterize acoustic energy flow surrounding underwater objects in the near field condition. To accomplish this, we employ prototype acoustic vector sensors which simultaneously measure acoustic pressure and three-dimensional acoustic particle acceleration at a singular point, allowing for precise vector field measurements. In March of 2018, a test at the U.S. Navy’s Dodge Pond Test Facility examined the intensity field surrounding hollow spheres at low ka (wavenumber × radius) values. Phase differences between varying acoustic path lengths from reflected, scattered, and creeping waves result in interference patterns around the object. Various intensity processing techniques are used to reconstruct the acoustic field. Instantaneous intensity describes the time-dependent energy flux of the field and can be divided into active (real) and reactive (imaginary) components, which represent physically real elements. Time-averaged intensity shows energy transport and can be visualized in the form of acoustic streamlines.

The respiratory control system is sexually dimorphic. In many brain regions, including respiratory motor nuclei, serotonin (5HT) levels are higher in females than in males. We hypothesized that there could be sex differences in 5HT input to the hypoglossal nucleus, a region of the brainstem involved in upper airway control. Adult Fischer 344 rats were anesthetized and a retrograde transsynaptic neuroanatomical tracer, Bartha pseudorabies virus (PRV), was injected into the tongue. Sections through the medulla were reacted immunocytochemically for the presence of (i) PRV, (ii) tryptophan hydroxylase (TPH; marker of 5HT neurons), (iii) PRV combined with TPH, and (iv) 5HT. Sex hormone levels were measured in female rats and correlated with TPH immunoreactivity, as hypoglossal 5HT levels vary with the estrous cycle. The number of PRV neurons was comparable in male and female rats. The number and distribution of TPH immunoreactive neurons in the caudal raphe nuclei were similar in male and female rats. The subset of 5HT neurons that innervate hypoglossal motoneurons was also similar in male and female rats. With the exception of the ventrolateral region of the hypoglossal nucleus, 5HT immunoreactivity was similar in male and female rats. These data suggest that sex differences in 5HT modulation of hypoglossal motoneurons in male and female rats are not the result of sex differences in TPH or 5HT, but may result from differences in neurotransmitter release and reuptake, location of 5HT synaptic terminals on hypoglossal motoneurons, pre- and postsynaptic 5HT receptor expression, or the distribution of sex hormone receptors on hypoglossal or caudal raphe neurons.

Hypertension is an important public health issue in Zambia. Despite the need for early detection, treatment, and ongoing monitoring, there is little documented research on hypertension in Zambia. The study aims were to: 1) better understand risk factors for hypertension in urban and rural communities in Mongu and Limulunga Districts, Western Province; 2) identify current health practices for hypertension and prevention in these communities; and 3) explore intersections between culture and hypertension perceptions and practices for study participants. A mixed methods approach was used; 203 adults completed surveys including demographics, anthropometric measures, blood pressure (BP), physicial activity, diet, and salt intake at five health check stations. Two focus groups were conducted with rural and urban community members to better understand their perspectives on hypertension. The prevalence of hypertension was 32.8% for survey participants. A further 24.6% had pre-hypertension. The mean total weight of salt added to food was nearly double the WHO recommendation with women adding significantly more salt to food than men. Significant differences in waist circumference were observed between men and women with men at low risk and women at substantialy high risk. In focus groups, participants cited westernized diets, lack of physical activity, stress, psychological factors, and urbanization as causative factors for hypertension. Participants lacked understanding of BP medications, healthy lifestyles, adherence to treatment, and ongoing monitoring. Focus group participants mentioned challenges in obtaining treatment for hypertension and desired to be active contributors in creating solutions. They recommended that government priorize hypertension initiatives that increase access to health education to reduce risk, enhance early detection, and support lifestyle changes and medication adherence. Our findings suggest that policy-makers need to engage communities more effectively to develop successful public health strategies to prevent, detect, and manage hypertension in Western Province, Zambia, particularly in rural areas.

The expense and limited availability of shikimic acid isolated from plants has impeded utilization of this hydroaromatic as a synthetic starting material. Although recombinant Escherichia coli catalysts have been constructed that synthesize shikimic acid from glucose, the yield, titer, and purity of shikimic acid are reduced by the sizable concentrations of quinic acid and 3-dehydroshikimic acid that are formed as byproducts. The 28.0 g/L of shikimic acid synthesized in 14% yield by E. coli SP1.1/pKD12.138 in 48 h as a 1.6:1.0:0.65 (mol/mol/mol) shikimate/quinate/dehydroshikimate mixture is typical of synthesized product mixtures. Quinic acid formation results from the reduction of 3-dehydroquinic acid catalyzed by aroE-encoded shikimate dehydrogenase. Is quinic acid derived from reduction of 3-dehydroquinic acid prior to synthesis of shikimic acid? Alternatively, does quinic acid result from a microbe-catalyzed equilibration involving transport of initially synthesized shikimic acid back into the cytoplasm and operation of the common pathway of aromatic amino acid biosynthesis in the reverse of its normal biosynthetic direction? E. coli SP1.1/pSC5.214A, a construct incapable of de novo synthesis of shikimic acid, catalyzed the conversion of shikimic acid added to its culture medium into a 1.1:1.0:0.70 molar ratio of shikimate/quinate/dehydroshikimate within 36 h. Further mechanistic insights were afforded by elaborating the relationship between transport of shikimic acid and formation of quinic acid. These experiments indicate that formation of quinic acid during biosynthesis of shikimic acid results from a microbe-catalyzed equilibration of initially synthesized shikimic acid. By apparently repressing shikimate transport, the aforementioned E. coli SP1.1/pKD12.138 synthesized 52 g/L of shikimic acid in 18% yield from glucose as a 14:1.0:3.0 shikimate/quinate/dehydroshikimate mixture.

To evaluate efficacy of a topical epidural analgesia used alone, or in combination with hydromorphone, against a standard pain protocol for the 48 hours immediately after hemilaminectomy.Randomized, blinded, controlled, clinical trial.Dogs (n = 30) with thoracolumbar intervertebral disc disease treated with hemilaminectomy.Dogs were randomly divided into 3 groups: group 1 received intermittent hydromorphone postoperatively, group 2 received a topical epidural of preservative-free morphine and dexmedetomidine administered via gel foam, group 3 received both forms of analgesia. All dogs were monitored and assessed for pain for 48 hours immediately postoperatively. Data were analyzed using MANOVA and Wilcoxon Rank Sum Tests.There was a significant temporal difference in treatment groups 1 and 3 when using a 0-10 pain scale (MANOVA, P = .02). There was also a significant difference at the 48th hour postoperatively between groups 1 and 3 (Wilcoxon Rank Sum Test).Topical epidural of preservative-free morphine and dexmedetomidine administered via gelfoam is not sufficient analgesia alone post hemilaminectomy but in conjunction with other opioid administration may lead to superior pain relief.

Male blue monkeys ( Cercopithecus mitis stuhlmanni ) of Budongo Forest, Uganda, produce two acoustically distinct alarm calls: hacks to crowned eagles ( Stephanoaetus coronatus ) and pyows to leopards ( Panthera pardus ) and a range of other disturbances. In playback experiments, males responded to leopard growls exclusively with a series of pyows and to eagle shrieks predominantly with hacks. Responses to playbacks of these alarm call series matched the responses to the corresponding predators, suggesting that the calls conveyed something about the nature of the threat. When responding to a series of hacks, indicating an eagle, males responded predominately with hacks, but produced significantly more calls if their group members were close to the playback stimulus than far away, regardless of their own position. When responding to a series of pyows, indicating a range of disturbances, males responded with pyows, but call rates were independent of the distance of other group members. The results suggest that males took into account the degree of danger experienced by other group members.

A series of recombinant Escherichia coli strains have been constructed and evaluated for their ability to synthesize p-hydroxybenzoic acid from glucose under fed-batch fermentor conditions. The maximum concentration of p-hydroxybenzoic acid synthesized was 12 g/L and corresponded to a yield of 13% (mol/mol). Synthesis of p-hydroxybenzoic acid began with direction of increased carbon flow into the common pathway of aromatic amino acid biosynthesis. This was accomplished in all constructs with overexpression of a feedback-insensitive isozyme of 3-deoxy-D-arabino-heptulosonic acid 7-phosphate synthase. Expression levels of enzymes in the common pathway of aromatic amino acid biosynthesis were also increased in all constructs to deliver increased carbon flow from the beginning to the end of the common pathway. A previously unreported inhibition of 3-dehydroquinate synthase by L-tyrosine was discovered to be a significant impediment to the flow of carbon through the common pathway. Chorismic acid, the last metabolite of the common pathway, was converted into p-hydroxybenzoic acid by ubiC-encoded chorismate lyase. Constructs differed in the strategy used for overexpression of chorismate lyase and also differed as to whether mutations were present in the host E. coli to inactivate other chorismate-utilizing enzymes. Use of overexpressed chorismate lyase to increase the rate of chorismic acid aromatization was mitigated by attendant decreases in the specific activity of DAHP synthase and feedback inhibition caused by p-hydroxybenzoic acid. The toxicity of p-hydroxybenzoic acid towards E. coli metabolism and growth was also evaluated.