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Body coloration in ectotherms serves multiple biological functions, including avoiding predators, communicating with conspecific individuals, and involvement in thermoregulation. As ectotherms rely on environmental sources of heat to regulate their internal body temperature, stable melanistic body coloration or color change can be used to increase or decrease heat absorption and heat exchange with the environment. While the function of melanistic coloration for thermoregulation has been found to increase solar radiation absorption for heating in many diurnal ectotherms, research on crepuscular and nocturnal ectotherms is lacking. Since crepuscular and nocturnal ectotherms generally absorb heat from the substrate, coloration is likely under different selective pressures than in diurnal ectotherms. We tested if the proportion of dorsal melanistic body coloration is related to differences in body temperature heating and cooling rates in the crepuscular geckoEublepharis maculariusand whether changes in environmental temperature trigger color changes in this species. Temperature measurements of the geckos and of the environment were taken using infrared thermography and temperature loggers. Color data were obtained using objective photography and a newly developed custom software package. We found that body temperature reflected substrate temperatures, and that the proportion of melanistic coloration has no influence on heating or cooling rates or on color changes. These findings suggest that, inE. macularius, melanistic coloration may not be used for thermoregulation. Future research should further test the function of melanistic coloration in other crepuscular and nocturnal vertebrates to understand the evolution of melanistic pattern in animals active in low light conditions.

Cr-Si based-alloys are promising candidates due to their high melting point and good oxidation resistance. They are designed for working temperatures beyond Ni-base superalloys. The major drawbacks of Cr- based alloys are the embrittlement by Cr2N formation and high ductile to brittle transition temperatures (DBTT). This work investigates the effect of alloying Cr-Si-alloys with the elements Fe and Ni and targets the microstructure and precipitation of A15 phase. Varied compositions are manufactured by arc-melting and heat treatment at 1200°C, which enables controlled precipitation hardening by the Cr3Si-A15 phase.Ni can cause the effect of solution softening in Cr and increases the low-temperature ductility as a result. For Fe it is shown, that it stabilizes the two-phase structure consisting of nitration resistant A15 phase and Crss. Oxidation exposures at 1200°C in synthetic air indicate that Fe additions up to 5 at.% increase also the nitridation resistance of Crss.

Reward processing is important for understanding behavior in psychopathology. Opportunities to earn money activate the ventral striatum, as shown by the monetary incentive delay (MID) task. Anxiety conditions have been modeled by presenting shocks and startling sounds. To further investigate the co-occurrence of an anxiety condition and a rewarding stimulus, we modified the MID to include a sustained threat of scream. This study investigated neural patterns of the MID task with an uncertain threat of a startling scream. Forty-three young adults completed a functional MRI scan. The task included two conditions (scream and safe) and three cues (gain $5, gain $0, lose $5). Analyses included a whole brain, group analysis using a linear mixed-effects model and a paired t-test. The whole brain analysis revealed a main effect of cue, with increased ventral striatal activation (F2,210 = 58.8, p < 0.001) during cues to gain or lose $5. We observed a main effect of condition during cue presentation, such that bilateral insula and putamen activation was diminished (p < 0.001) in the scream versus the safe condition. A t-test of condition showed increased activation during threat blocks in the insula and putamen. A time course graph revealed that activation in the insula and putamen responded similarly to incentive but had an overall elevation during the scream condition. These results replicated expected activation in reward and in the setting of uncertain threat. Our results show that uncertain threat increases the magnitude of activation in the dorsal striatum.

When studying how species will respond to climatic change, a common goal is to predict how species distributions change through time. Environmental niche models (ENMs) are commonly used to estimate a species’ environmental niche from observed patterns of occurrence and environmental predictors. However, species distributions are often shaped by non-environmental factors–including biotic interactions and dispersal barriers—truncating niche estimates. Though a truncated niche estimate may accurately predict present-day species distribution within the sampled area, this accuracy decreases when predicting occurrence at different places and under different environmental conditions. Modeling niche in a phylogenetic framework leverages a clade’s shared evolutionary history to pull species estimates closer towards phylogenetic conserved values and farther away from species specific biases. We propose a new Bayesian model of phylogenetic niche estimation implemented in R called BePhyNE (Bayesian environmental Phylogenetic Niche Estimation). Under our model, species ENM parameters are transformed into biologically interpretable continuous parameters of environmental niche optimum, breadth, and tolerance evolving as a multivariate Brownian motion. Through simulation analyses, we demonstrate model accuracy and precision that improve as phylogeny size increases. We also demonstrate our model on eastern United States Plethodontid salamanders and recover accurate estimates of species niche, even when species occurrence data is lacking and entirely informed by the evolutionary model. Our model demonstrates a novel framework where niche changes can be studied forwards and backwards through time to understand ancestral ranges, patterns of environmental specialization, and estimate niches of data-deficient species.

With the fast growth of renewable energy sources (RES), more and more uncertainties are involved and influencing the stable operation of power systems. Controlled islanding is the last measure to prevent power system blackouts, thus this paper aims to propose a novel model of system separation based on Online Coherency Identification and Adjustable Robust Optimization Programming (OCI-AROP) for minimizing load shedding considering the uncertainties of RES. First, Fuzzy C-Means (FCM) clustering method with F -statistics is utilized to identify the coherent generator groups with the frequency data measured by Phasor Measurement Units (PMUs). Then, the OCI-AROP model considering coherent group constraints, connectivity constraints and robustness constraints about RES are presented. Finally, the case studies on IEEE-39 bus system and WECC-179 bus system are employed to demonstrate the effectiveness of the proposed OCI-AROP model, and comparisons among the OCI-AROP model and the other models are also given to show its superiority.

The Parkinson's disease (PD) risk gene GTP cyclohydrolase 1 (GCH1) catalyzes the rate-limiting step in tetrahydrobiopterin (BH4) synthesis, an essential cofactor in the synthesis of monoaminergic neurotransmitters. To investigate the mechanisms by which GCH1 deficiency may contribute to PD, we generated a loss of function zebrafishgch1mutant (gch1–/–), using CRISPR/Cas technology.gch1–/–zebrafish develop marked monoaminergic neurotransmitter deficiencies by 5 d postfertilization (dpf), movement deficits by 8 dpf and lethality by 12 dpf. Tyrosine hydroxylase (Th) protein levels were markedly reduced without loss of ascending dopaminergic (DAergic) neurons. L-DOPA treatment ofgch1–/–larvae improved survival without ameliorating the motor phenotype. RNAseq ofgch1–/–larval brain tissue identified highly upregulated transcripts involved in innate immune response. Subsequent experiments provided morphologic and functional evidence of microglial activation ingch1–/–. The results of our study suggest that GCH1 deficiency may unmask early, subclinical parkinsonism and only indirectly contribute to neuronal cell death via immune-mediated mechanisms. Our work highlights the importance of functional validation for genome-wide association studies (GWAS) risk factors and further emphasizes the important role of inflammation in the pathogenesis of PD.SIGNIFICANCE STATEMENTGenome-wide association studies have now identified at least 90 genetic risk factors for sporadic Parkinson's disease (PD). Zebrafish are an ideal tool to determine the mechanistic role of genome-wide association studies (GWAS) risk genes in a vertebrate animal model. The discovery of GTP cyclohydrolase 1 (GCH1) as a genetic risk factor for PD was counterintuitive, GCH1 is the rate-limiting enzyme in the synthesis of dopamine (DA), mutations had previously been described in the non-neurodegenerative movement disorder dopa-responsive dystonia (DRD). Rather than causing DAergic cell death (as previously hypothesized by others), we now demonstrate that GCH1 impairs tyrosine hydroxylase (Th) homeostasis and activates innate immune mechanisms in the brain and provide evidence of microglial activation and phagocytic activity.

Among other tests, Barts Health NHS Trust clinical transplantation laboratory conducts two important gene-detection tests: human leucocyte antigen (HLA)-B*27 (‘B27’, associated with the diagnosis of ankylosing spondylitis) and HLA-B*57:01 (‘B57’, associated with prediction of abacavir hypersensitivity disorder). The turnaround time (TaT) from sample receipt to return of results is important to clinicians and their patients but was not monitored. Furthermore, we anticipated an imminent increase in demand from a forthcoming pathology service merger, together with long-term increases with the rise of personalised genetic medicine.In this quality improvement project, we identified current TaT performance and sources of delay. Over three plan-do-study-act (PDSA) cycles, we tested three change ideas, two involving using IT to remove manual administrative steps and alert us to samples needing progressing; both were retained. The other change involved separating out the targeted tests; we judged this not worthwhile with current demand levels, although something to be re-examined when volumes increase. During the project, we reduced mean TaT from 3.8 to 3.3 days and increased the proportion within our 5-day target from 78% to 100%. These have been sustained (at 3.4 days and 97%) for the 3 months following our PDSA cycles and illustrate that reducing variation can be as impactful as reducing the mean.We conducted this project during the COVID-19 disruption, which reduced demand substantially. We took advantage of this to allow staff to spend time on these improvement activities. Another interesting feature of the work is that during the project, we compared changes in performance on our targeted B27/B57 tests with that on another comparable test as a control, to consider the impact of the general increased attention (the Hawthorne effect). We found that performance on this control also increased comparably, but then fell away after our project finished, while it did not for B27/B57.

In contrast to management optimisation methods, which quantify decision variables to create plans, this study does not seek the “best” strategy. Instead, it simulates the sequential decision-making process implicit in environmental management, so that the effectiveness of management scenarios, when implemented as intended, can be evaluated. The purpose was to develop a methodology to quantitatively evaluate the effectiveness of groundwater management plans by simulating sequential management decisions that evolve based on aquifer/management feedback. A groundwater management scheme was structured as a system control loop to capture the aquifer/management feedback, and management decisions were based on realistically sparse observation times and locations. The method indicates how a plan may proceed in reality under alternate timings and frequencies of management decisions and in systems with differing response times. A synthetic example quantified the impact of a generic plan, specifying environmental objectives, extraction restrictions and entitlement limits (maximum volume/year that users are permitted), relative to no-management by combining a numerical model of “reality” with management rules under a stochastic climate. The management decision-making frequency varied from daily to decadal. Generally, effectiveness decreased as the interval between management interventions increased and intervals greater than annual showed minimal improvement compared to entitlement only. The timing of management decisions relative to the irrigation season also impacted plan effectiveness, and when decisions were made prior to the irrigation season, quarterly management was less effective than annual and biannual management. By testing the capacity of plans to achieve objectives, groundwater management can be systematically and objectively improved.

Forward-head posture (FHP) is a common postural deviation associated with older age, cervical muscle weakness, poor balance, anteriorly displaced center of mass, increased postural sway and fall risk, impaired cervical proprioception, and possibly vestibular dysfunction. Studies have found increased fall risk in older adults with FHP but have not identified a casual reason for this relationship. This review aims to examine the links between (FHP) and vestibular deficits. While assessment of overall posture, including FHP, is a common component of a physical therapy evaluation, a standardized method of clinical measurement for FHP is lacking. The craniovertebral angle (CVA) appears to be the most reliable method, with FHP defined as less than or equal to 44–53 degrees. Studies where FHP is measured using the CVA appear to be more accurate in identifying associations between this postural deviation and factors that impact postural control in older adults, such as balance and cervical proprioception. Limited studies have found FHP to be associated with duration of clinical symptoms of vestibular disease. FHP also heightens age-related increases in anterior-posterior postural sway. Compelling evidence exists that links FHP with vestibular deficits, increased fall risk, and impaired cervical proprioception. Further research using CVA and a consistent definition of FHP is needed to answer this question and develop clinical practice guidelines.

Purpose Idiopathic intracranial hypertension is a significant cause of preventable blindness. Patients suffer from debilitating headaches, pulsatile tinnitus, nausea, vomiting, photophobia and radicular pain. At this rate, treatment cost will increase to 462.7 million pounds sterling annually by 2030. Weight loss is the only proven disease-modifying therapy for reversal of idiopathic intracranial hypertension. Bariatric surgery leads to superlative weight loss and reversal of related comorbidities. The case series and literature review aim to raise awareness of bariatric surgery as a safe and effective treatment modality for idiopathic intracranial hypertension. Material and Methods The literature review comprises three systematic analysis and one randomised control trial which were identified after a PubMed search. In the case series, we have included four patients with a preoperative diagnosis of long-standing idiopathic intracranial hypertension. They were referred to our department for bariatric surgery by the neuro-ophthalmologist between January and December 2018. They were followed up for 2 years after bariatric surgery. Results All four patients were women with a mean age of 34 years. Mean body mass index reduced from 47.3 kg/m2 before surgery to 30 kg/m2 at the end of 2 years after surgery. They showed significant improvement or resolution in their symptoms related to idiopathic intracranial hypertension, and none of them required further cerebrospinal fluid pressure reducing procedures. Conclusion Bariatric surgery is a safe and effective method of treating idiopathic intracranial hypertension. It is superior compared to medical management and cerebrospinal fluid pressure reducing procedures which have high rates of recurrence.

What is in store for the future of OCT technology?

Purpose: With the increasing burden of chronic pain and opioid use, provider shortages in Eastern Kentucky and West Virginia have experienced many challenges related to chronic pain management. This study tested a practice facilitator model in both academic and community clinics that selected and implemented best practice processes to better assist patients with chronic pain and increase the use of interdisciplinary health care services. Methods: Using a quasi-experimental design, a practice facilitator was assigned to each state’s clinics and trained clinic teams in quality improvement methods to implement chronic pain tool(s) and workflow processes. Charts for 695 patients with chronic pain using opioids, from 8 randomly selected clinics in eastern Appalachia, were reviewed to assess for changes in clinic processes. Results: Statistically significant improvements were found in 10 out of 16 chronic pain best practice process measures. These included improved workflow implementation (P < 0.001), increased urine drug screen test orders (P = 0.001) and increased utilization of controlled medication agreements (P = 0.004). In total, 7 of 8 clinics significantly improved in at least one, if not all, selected and implemented process measures. Conclusions: Our findings indicate that practice facilitation, standardization of workflows and formation of structured clinical teams can improve processes of care in chronic pain management and facilitate the use of interdisciplinary services. Future studies are needed to assess long-term patient-centered outcomes that may result from improved processes of chronic pain care.

Purpose. This study investigates the virulence and antimicrobial resistance in association with common clonal complexes (CCs) of enteroaggregative Escherichia coli (EAEC) isolated from Bangladesh. The aim was to determine whether specific CCs were more likely to be associated with putative virulence genes and/or antimicrobial resistance. Methodology. The presence of 15 virulence genes (by PCR) and susceptibility to 18 antibiotics were determined for 151 EAEC isolated from cases and controls during an intestinal infectious disease study carried out between 2007–2011 in the rural setting of Mirzapur, Bangladesh (Kotloff KL, Blackwelder WC, Nasrin D, Nataro JP, Farag TH et al. Clin Infect Dis 2012;55:S232–S245). These data were then analysed in the context of previously determined serotypes and clonal complexes defined by multi-locus sequence typing. Results. Overall there was no association between the presence of virulence or antimicrobial resistance genes in isolates of EAEC from cases versus controls. However, when stratified by clonal complex (CC) one CC associated with cases harboured more virulence factors (CC40) and one CC harboured more resistance genes (CC38) than the average. There was no direct link between the virulence gene content and antibiotic resistance. Strains within a single CC had variable virulence and resistance gene content indicating independent and multiple gene acquisitions over time. Conclusion. In Bangladesh, there are multiple clonal complexes of EAEC harbouring a variety of virulence and resistance genes. The emergence of two of the most successful clones appeared to be linked to either increased virulence (CC40) or antimicrobial resistance (CC38), but increased resistance and virulence were not found in the same clonal complexes.

Groundwater is the world's largest freshwater resource and due to overextraction, levels have declined in many regions causing extensive social and environmental impacts. Groundwater management seeks to balance and mitigate the detrimental impacts of development, with plans commonly used to outline management pathways. Thus, plan efficiency is crucial, but seldom are plans systematically and quantitatively assessed for effectiveness. This study frames groundwater management as a system control problem in order to develop a novel testability assessment rubric to determine if plans meet the requirements of a control loop, and subsequently, whether they can be quantitatively tested. Seven components of a management plan equivalent to basic components of a control loop were determined, and requirements of each component necessary to enable testability were defined. Each component was weighted based upon proposed relative importance, then segmented into rated categories depending on the degree the requirements were met. Component importance varied but, a defined objective or acceptable impact was necessary for plans to be testable. The rubric was developed within the context of the Australian groundwater management industry, and while use of the rubric is not limited to Australia, it was applied to 15 Australian groundwater management plans and approximately 47% were found to be testable. Considering the importance of effective groundwater management, and the central role of plans, our lack of ability to test many plans is concerning.

Emma White highlights the latest developments in optical coherence tomography (OCT) technology, for the early detection and monitoring of major eye conditions, from faster scan times and enhanced fundus imaging to remote operation for safe social distancing

Objective Obesity is associated with a high incidence of obstructive sleep apnoea (OSA). Bariatric surgery is postulated to lead to OSA resolution, but there is inconclusive evidence on its efficacy. We used objective measurements to determine the rate of resolution or improvement of OSA in patients who had bariatric procedures in our unit. Results Data was analysed on all patients with OSA who underwent bariatric procedures [laparoscopic Roux-en-Y gastric bypass (LRYGB) and sleeve gastrectomy (LSG)] between June 2012 and September 2016 in our unit. 47 patients (26.7%) were diagnosed with OSA. Mean age was 48.5 years. 63.8% were female. 43 required nocturnal continuous positive airway pressure (CPAP) support. Procedures were LRYGB (n = 26) and LSG (n = 21). Mean excess weight loss was 56.1%. Mean start apnoea-hypopnoea index (AHI) on CPAP was 6.4 events/hr and end AHI was 1.4 events/h. 14 patients (32.6%) had complete OSA resolution and 12 (27.9%) showed improvement in pressure support requirements. We demonstrated that 55.3% of patients had resolution or improvement in OSA following bariatric surgery. However, there was a high rate of non-attendance of follow-up appointments. Future efforts will involve analysis of the reasons for this to ensure more robust monitoring.

Emma White looks at the rise of global myopia and the range of treatment options available to practitioners