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Optimisation-based control design techniques are applied to multicopters with variable-RPM rotors. The handling qualities and motor current requirements of a quadcopter, hexacopter and octocopter with equal gross weights (5,360N) and total disk areas (producing a 287N/m $^2$ disk loading) are compared in hover. For axes that rely on the rotor thrust (all except yaw), the increased inertia of the larger rotors on the quadcopter increase the current requirement, relative to vehicles with fewer, smaller rotors. Both the quadcopter and hexacopter have maximum current margin requirements (relative to hover) during a step command in longitudinal velocity. In yaw, rotor inertia is irrelevant, as the reaction torque of the motor is the same whether the rotor is accelerating or overcoming drag. This, combined with the octocopter's greater inertia as well as the fact that it requires 30% less current to drive its motors in hover, results in the octocopter requiring the greatest current margin, relative to hover conditions. To meet handling qualities requirements, the total weight of the motors of the octocopter and hexacopter is comparable at 13.5% weight fraction, but the quadcopter's motors are heavier, requiring 16% weight fraction. If the longitudinal and lateral axes were flown in ACAH mode, rather than TRC mode, the total motor weight of all configurations would be nearly identical, requiring about 13.5% weight fraction for motors (compared to 7–9% weight fraction from hover torque requirements). [ABSTRACT FROM AUTHOR]

This study focuses on vibration reduction for quadcopters and octocopters with elastic, two-bladed, fixed-speed, variable-pitch rotors through the use of relative rotor phasing. The study defines phase modes such as a pitch phase mode with relative phasing between the front and aft rotors, a roll phase mode with relative phasing between the left and right rotors, and a differential phase mode with relative phasing between the clockwise and counter-clockwise spinning rotors for both the quadcopter and the octocopter, as well as additional higher harmonic phase modes for the octocopter. Parametric studies on individual phase modes indicate that, for the quadcopter in forward flight, the pitch and roll phase modes can almost entirely eliminate the 2/rev vibratory forces (at the aircraft level), but the 2/rev vibratory moments cannot be minimised at the same time. By simultaneously using multiple phase modes, a Pareto front can be generated and a solution selected based on the relative emphasis on force or moment vibration reduction. For the octocopter, it was observed that individual higher harmonic modes (specifically the 2 c or 2 s modes) could almost entirely eliminate both the 2/rev vibratory forces and moments, simultaneously. Compared with vibration levels in forward flight that might, on average, be expected if the rotors were randomly phased, a 62% reduction of a composite vibration index can be achieved on a quadcopter, and complete elimination of vibration was achievable on an octocopter, with appropriate rotor phasing. [ABSTRACT FROM AUTHOR]

The properties of disordered metamaterial absorbers are analyzed on the basis of numerical simulations and experimental characterizations. A broadening of the absorption spectrum is clearly evidenced. This effect is the consequence of both the coupling between nearby resonators leading to the occurrence of extended magnetic resonance modes and the interconnection of elementary particles yielding the definition of resonating clusters. The angular robustness of the absorbing structure under oblique incidence is also demonstrated for a wide domain of angles. [ABSTRACT FROM AUTHOR]

The climate models are extremely complex pieces of software. They reflect best knowledge on physical components of the climate, nevertheless, they contain several parameters, which are too weakly constrained by observations, and can potentially lead to a crash of simulation. Recently a study by Lucas et al. (2013) has shown that machine learning methods can be used for predicting which combinations of parameters can lead to crash of simulation, and hence which processes described by these parameters need refined analyses. In the current study we reanalyse the dataset used in this research using different methodology. We confirm the main conclusion of the original study concerning suitability of machine learning for prediction of crashes. We show, that only three of the eight parameters indicated in the original study as relevant for prediction of the crash are indeed strongly relevant, three other are relevant but redundant, and two are not relevant at all. We also show that the variance due to split of data between training and validation sets has large influence both on accuracy of predictions and relative importance of variables, hence only cross-validated approach can deliver robust prediction of performance and relevance of variables. [ABSTRACT FROM AUTHOR]

Objectives: (1) Assess and compare the perceptions of pet owners and veterinary professionals pertaining to the extent of veterinary workforce and access to care challenges in 2023 in Colorado, and (2) Assess what programs, policies, and resources veterinary professionals and pet owners believe would be most effective at addressing access to care and workforce challenges in Colorado., Sample: 736 veterinarians, veterinary technicians, or practice/owner manager ("veterinary professionals") in Colorado. A total of 1,209 pet owners (919 from an online survey and 290 from in-person surveying)., Procedures: Distribution of an online anonymous survey to veterinary professionals in Colorado. Pet owners were surveyed both online and in-person at pet pantry or shelter events., Results: Veterinary professionals reported significant workforce challenges, including having to frequently divert clients, clients forced to decline medical care or having to euthanize their pets due to cost. Veterinary professionals were especially supportive of policy efforts to enhance recruitment and retention of technicians, including through mechanisms such as clarifying their scope of practice, loan repayment programs, and enhancing career pathways. Colorado pet owners' responses pertaining to the scope of access to care challenges were similar to prior national research. Pet owners reported particularly needing low-cost emergency clinics in their community as well as resources to reduce the cost of care. Pet owners were generally supportive of expanding veterinary care access through telemedicine; indicating they would feel comfortable seeing a veterinarian via telemedicine, even for the first time, and that expanded use of telemedicine would increase their ability to obtain care., Conclusions and Clinical Relevance: Colorado pet owners and veterinary professionals both identified numerous access to care challenges as well as indicated support for the development of several potential initiatives to address the problem. Low-cost clinics that provide sick and emergency care was the resource rated as being most helpful among pet owners. Further exploration of grants, voucher programs, expansion of telemedicine, increased utilization and title protection for CVTs, and the creation of the veterinary professional associate position are all initiatives that were noted to be worthy of further exploration., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Niemiec, Champine, Frey, Lobdell, Steele, Vaiden, Kogan and Mertens.)

Background: Sacubitril/valsartan, an angiotensin receptor-neprilysin inhibitor (ARNI), has demonstrated a survival benefit and reduces heart failure hospitalization in patients with heart failure with reduced left ventricular ejection fraction (HFrEF); however, our experience in this field is limited. This study aimed to summarize a real clinical practice of the use of ARNI in HFrEF patients hospitalized due to HFrEF in the era before the 2021 ESC HF recommendations, as well as assess their clinical outcome with regard to ARNI administration., Methods and Materials: Overall, 613 patients with HFrEF hospitalized in 2018-2020 were enrolled into a retrospective one-centre cross-sectional analysis. The study population was categorized into patients receiving (82/13.4%) and not-receiving (531/82.6%) ARNI. Clinical outcomes defined as rehospitalization, number of rehospitalizations, time to the first rehospitalization and death from any cause were analysed in the 1-2 year follow-up in the ARNI and non-ARNI groups, matched as to age and LVEF., Results: Clinical characteristics revealed the following differences between ARNI and non-ARNI groups: A higher percentage of cardiovascular implantable electronic devices (CIED) ( p = 0.014) and defibrillators with cardiac resynchronization therapy (CRT-D) ( p = 0.038), higher frequency of atrial fibrillation ( p = 0.002) and history of stroke ( p = 0.024) were in the ARNI group. The percentage of patients with HFrEF NYHA III/IV presented an increasing trend to be higher in the ARNI (64.1%) as compared to the non-ARNI group (51.5%, p = 0.154). Incidence of rehospitalization, number of rehospitalizations and time to the first rehospitalization were comparable between the groups. There were no differences between the numbers of deaths of any cause in the ARNI (28%) and non-ARNI (28%) groups. The independent negative predictor of death in the whole population of ARNI and non-ARNI groups was the coexistence of coronary artery disease (CAD) (beta= -0.924, HR 0.806, p = 0.011)., Conclusions: Our current positive experience in ARNI therapy is limited to extremely severe patients with HFrEF. Regardless of the more advanced HF and HF comorbidities, the patients treated with ARNI presented similar mortality and rehospitalizations as the patients treated by standard therapy.

Background and Objectives: Regardless of the improvement in key recommendations in non-ST-elevation myocardial infarction (NSTEMI), the prevalence of total occlusion (TO) of infarct-related artery (IRA), and the impact of TO of IRA on outcomes in patients with NSTEMI, remain unclear. Aim: The study aimed to assess the incidence and predictors of TO of IRA in patients with NSTEMI, and its clinical significance. Material and Methods: The study was a single-center retrospective cohort analysis of 399 consecutive patients with NSTEMI (293 male, mean age: 71 ± 10.1 years) undergoing percutaneous coronary intervention. The study population was categorized into patients with TO and non-TO of IRA on coronary angiography. In-hospital and one-year mortality were analyzed. Results: TO of IRA in the NSTEMI population occurred in 138 (34.6%) patients. Multivariate analysis identified the following independent predictors of TO of IRA: left ventricular ejection fraction (odds ratio (OR) 0.949, p < 0.001); family history of coronary artery disease (CAD) (OR 2.652, p < 0.001); and high-density lipoprotein (HDL) level (OR 0.972, p = 0.002). In-hospital and one-year mortality were significantly higher in the TO group than the non-TO group (2.8% vs. 1.1%, p = 0.007 and 18.1% vs. 6.5%, p < 0.001, respectively). The independent predictors of in-hospital mortality were: left ventricular ejection fraction (LVEF) at admission (OR 0.768, p = 0.004); and TO of IRA (OR 1.863, p = 0.005). Conclusions: In the population of patients with NSTEMI, TO of IRA represents a considerably frequent phenomenon, and corresponds with impaired outcomes. Therefore, the utmost caution should be paid to prevent delay of coronary angiography in NSTEMI patients with impaired left ventricular systolic function, metabolic disturbances, and a family history of CAD, who are at increased risk of TO of IRA.

Shifting the public towards plant-based diets is critical for achieving environmental and public health outcomes. Increasingly news articles and organizations have begun using the saliency of the COVID-19 crisis to highlight the link between animal agriculture, pandemic risks, and other widespread public health threats. Yet, little is known about the effectiveness of this messaging strategy for motivating dietary change. We conducted a randomized trial with an online sample to examine the impact of: (1) a message that uses the saliency of the COVID-19 pandemic to highlight the risk of disease transmission from factory farms, and (2) a message that uses the saliency of the COVID-19 pandemic to highlight the threat to worker's health created by factory farms. We examine whether these messages are more effective at changing beliefs about and behavioral intentions towards plant-based eating, as compared to more traditional messages that highlight the environmental, personal health, or animal welfare implications of factory farmed meat consumption. We find that all messages differentially influenced beliefs about the various negative consequences of meat consumption. However, these altered beliefs did not differentially motivate changes in respondents' intentions to reduce meat consumption and choose plant-based alternatives. This was possibly due to the numerous other barriers to behavior change identified in qualitative survey responses, such as cost, taste, and social factors. We did find that messages that highlight the personal health benefits of reduced meat consumption were more effective at increasing public trust in the message deliverer. Our results suggest that highlighting personal health benefits in messaging and addressing the additional identified barriers to behavior change may be critical for building trust and shifting the public towards plant-based diets., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Research suggests that encouraging motivated residents to reach out to others in their social network is an effective strategy for increasing the scale and speed of conservation action adoption. However, little is known about how to effectively encourage large numbers of residents to reach out to others about conservation causes. We examined the influence of normative and efficacy-based messaging at motivating residents to engage in and to encourage others to participate in native plant gardening in their community. To do so, we conducted a field experiment with messages on mailings and tracked native plant vouchers used. Efficacy messages tended to be more effective than normative messages at increasing residents' willingness to reach out to others to encourage conservation action, as indicated by a several percentage point increase in native plant voucher use by residents' friends and neighbors. Messages sometimes had different impacts on residents based on past behaviors and perceptions related to native plant gardening. Among these subgroups, efficacy and combined efficacy and norm messages most effectively encouraged individual and collective actions, as indicated by increased voucher usage. Our findings suggest that interventions that build residents' efficacy for engaging in a conservation behavior and for reaching out to others may be a promising path forward for outreach. However, given our results were significant at a false discovery rate cutoff of 0.25 but not 0.05, more experimental trials are needed to determine the robustness of these trends., (© 2021 The Authors. Conservation Biology published by Wiley Periodicals LLC on behalf of Society for Conservation Biology.)

Saliva has significant advantages as a test medium for detection of SARS-CoV-2 infection in patients, such as ease of collection, minimal requirement of supplies and trained personnel, and safety. Comprehensive validation in a large cohort of prospectively collected specimens with unknown SARS-CoV-2 status should be performed to evaluate the potential and limitations of saliva-based testing. We developed a saliva-based testing pipeline for detection of SARS-CoV-2 nucleic acids using real-time reverse transcription PCR (RT-PCR) and droplet digital PCR (ddPCR) readouts, and measured samples from 137 outpatients tested at a curbside testing facility and 29 inpatients hospitalized for COVID-19. These measurements were compared to the nasal swab results for each patient performed by a certified microbiology laboratory. We found that our saliva testing positively detects 100% (RT-PCR) and 93.75% (ddPCR) of curbside patients that were identified as SARS-CoV-2 positive by the Emergency Use Authorization (EUA) certified nasal swab testing assay. Quantification of viral loads by ddPCR revealed an extremely wide range, with 1 million-fold difference between individual patients. Our results demonstrate for both community screening and hospital settings that saliva testing reliability is on par with that of the nasal swabs in detecting infected cases, and has potential for higher sensitivity when combined with ddPCR in detecting low-abundance viral loads that evade traditional testing methods.

In the state of Colorado, a citizen ballot initiative to reintroduce gray wolves ( Canis lupus ) is eliciting polarization and conflict among multiple stakeholder and interest groups. Given this complex social landscape, we examined the social context surrounding wolf reintroduction in Colorado as of 2019. We used an online survey of 734 Coloradans representative in terms of age and gender, and we sampled from different regions across the state, to examine public beliefs and attitudes related to wolf reintroduction and various wolf management options. We also conducted a content analysis of media coverage on potential wolf reintroduction in 10 major daily Colorado newspapers from January 2019, when the signature-gathering effort for the wolf reintroduction initiative began, through the end of January 2020, when the initiative was officially added to the ballot. Our findings suggest a high degree of social tolerance or desire for wolf reintroduction in Colorado across geographies, stakeholder groups, and demographics. However, we also find that a portion of the public believes that wolves would negatively impact their livelihoods, primarily because of concerns over the safety of people and pets, loss of hunting opportunities, and potential wolf predation on livestock. These concerns-particularly those related to livestock losses-are strongly reflected in the media. We find that media coverage has focused only on a few of the many perceived positive and negative impacts of wolf reintroduction identified among the public. Our findings highlight the need to account for this diversity of perspectives in future decisions and to conduct public outreach regarding likely impacts of wolf reintroduction., Competing Interests: The authors declare that they have no competing interests.

Controlling invasive species presents a public-good dilemma. Although environmental, social, and economic benefits of control accrue to society, costs are borne by only a few individuals and organizations. For decades, policy makers have used incentives and sanctions to encourage or coerce individual actors to contribute to the public good, with limited success. Diverse, subnational efforts to collectively manage invasive plants, insects, and animals provide effective alternatives to traditional command-and-control approaches. Despite this work, there has been little systematic evaluation of collective efforts to determine whether there are consistent principles underpinning success. We reviewed 32 studies to identify the extent to which collective-action theories from related agricultural and environmental fields explain collaborative invasive species management approaches; describe and differentiate emergent invasive species collective-action efforts; and provide guidance on how to enable more collaborative approaches to invasive species management. We identified 4 types of collective action aimed at invasive species-externally led, community led, comanaged, and organizational coalitions-that provide blueprints for future invasive species management. Existing collective-action theories could explain the importance attributed to developing shared knowledge of the social-ecological system and the need for social capital. Yet, collection action on invasive species requires different types of monitoring, sanctions, and boundary definitions. We argue that future government policies can benefit from establishing flexible boundaries that encourage social learning and enable colocated individuals and organizations to identify common goals, pool resources, and coordinate efforts., (© 2018 The Authors. Conservation Biology published by Wiley Periodicals, Inc. on behalf of Society for Conservation Biology.)

We report on the exchange of orbital angular momentum between an electromagnetic wave and a 30 cm diameter ring. Using a turnstile antenna in the GHz range, we induce a torque on a suspended copper strip of the order of 10(-8)  N m. Rotations of a few degrees and accelerations up to 4×10(-4) °/s2 are observed. A linear dependence of the acceleration as a function of the applied power is found. There are many applications in the detection of angular momentum in electromagnetics, in acoustics, and also in the magnetization of nanostructures.

The Primary Care Behavioral Health Screen (PCBHS) is a self-report instrument developed to screen for behavioral health problems in primary care settings. The present paper describes development of the PCBHS and reports findings from item analyses and studies examining the instrument's convergent validity and test-retest reliability. Results suggest the PCBHS is a useful and valid method for screening a variety of behavioral health problems in a busy primary care practice. Recommendations for further research on the PCBHS are provided.

The primary care literature provides some useful information and several project examples for clinicians attempting to develop an integrated care practice, but prior discussion has been based largely on projects developed in government-funded or HMO systems. The current paper focuses on the business challenges of establishing an integrated care practice in a private, fee-for-service setting. Despite increasing commitment to the concept of the medical home, which embraces behavioral health care, physicians in the private sector remain cautious about proposed practice changes such as integrated care. There are additional obstacles that can impede successful implementation of integrated primary care in the private sector. The authors identify five major challenges and suggest potential strategies to address these challenges, drawing, in part, on their experience with a 4-year integrated primary care demonstration project., ((PsycINFO Database Record (c) 2013 APA, all rights reserved).)

Background & Aims: Crohn's disease (CD) and sarcoidosis (SA) are chronic inflammatory barrier diseases that share several clinical and immunological features, including the occurrence of granulomas., Methods: A 100k genome-wide association study with 83,360 single-nucleotide polymorphisms (SNPs) was performed on 382 CD patients, 398 SA patients, and 394 control individuals. The 24 SNPs that were most strongly associated in the combined CD/SA phenotype were selected for verification in an independent sample of 1,317 patients (660 CD and 657 SA) and 1,091 controls., Results: The most significant association (Bonferroni corrected P = .036) was obtained at SNP rs1398024 on chromosome 10p12.2, with an odds ratio (OR) for both diseases of 0.81 (95% confidence interval [CI], 0.69-0.96) for carriership of the rarer allele A. The P value in the overall combined sample was 4.24 x 10(-6). During further follow-up, a moderate association (OR, 0.83; 95% CI, 0.72-0.96; P = .015) was observed between rs1398024 and ulcerative colitis (1,080 patients vs 1,091 controls), the second main subphenotype of inflammatory bowel disease in addition to CD. Extensive fine mapping of the 10p12.2 locus points to yet unidentified variants in the C10ORF67 gene region as the most likely underlying risk factors., Conclusion: Our study demonstrates that the combined analysis of different, albeit clinically related, phenotypes can lead to the identification of common susceptibility loci.