Search

We used an internet-based survey platform to conduct a cross-sectional survey regarding the impact of COVID-19 on the LGBTQ + population in the United States. While this method of data collection was quick and inexpensive, the data collected required extensive cleaning due to the infiltration of bots. Based on this experience, we provide recommendations for ensuring data integrity. Recruitment conducted between May 7 and 8, 2020 resulted in an initial sample of 1251 responses. The Qualtrics survey was disseminated via social media and professional association listservs. After noticing data discrepancies, research staff developed a rigorous data cleaning protocol. A second wave of recruitment was conducted on June 11-12, 2020 using the original recruitment methods. The five-step data cleaning protocol led to the removal of 773 (61.8%) surveys from the initial dataset, resulting in a sample of 478 participants in the first wave of data collection. The protocol led to the removal of 46 (31.9%) surveys from the second two-day wave of data collection, resulting in a sample of 98 participants in the second wave of data collection. After verifying the two-day pilot process was effective at screening for bots, the survey was reopened for a third wave of data collection resulting in a total of 709 responses, which were identified as an additional 514 (72.5%) valid participants and led to the removal of an additional 194 (27.4%) possible bots. The final analytic sample consists of 1090 participants. Although a useful and efficient research tool, especially among hard-to-reach populations, internet-based research is vulnerable to bots and mischievous responders, despite survey platforms' built-in protections. Beyond the depletion of research funds, bot infiltration threatens data integrity and may disproportionately harm research with marginalized populations. Based on our experience, we recommend the use of strategies such as qualitative questions, duplicate demographic questions, and incentive raffles to reduce likelihood of mischievous respondents. These protections can be undertaken to ensure data integrity and facilitate research on vulnerable populations., Competing Interests: Conflict of interestNot applicable., (© The Author(s), under exclusive licence to Springer Nature B.V. 2021.)

The United Nations' increasing involvement in global sustainability culminated in 2015 with the release of the 2030 Agenda. This agenda puts businesses in the spotlight, and their innovation and stakeholder partnering activities are portrayed as essential strategies for achieving an ambitious set of 17 Sustainable Development Goals (SDGs). In this study, we identify six distinct dynamic stakeholder engagement strategies-resilient specialists, opportunity explorers, uncommitted diversifiers, rainbow warriors, rainbow washers, and progressive learners-and distinguish two approaches to innovate, depending on the range of SDG targets aimed to achieve simultaneously. On the one hand, for firms that take a narrow approach intended to achieve a reduced set of SDG targets, we predict that successful dynamic stakeholder engagement strategies are those that end up with an intensive collaboration with a reduced number of stakeholder groups. On the other hand, for firms adopting a broad innovation approach to satisfy a wide set of SDG targets, we predict that successful dynamic stakeholder engagement strategies are those that end up interacting with a wide number of stakeholder groups. Longitudinal analysis of more than 3900 Spanish firms supports our predictions and suggests clear implications for responsible innovation research and the advancement of sustainable development through collaboration., Competing Interests: Conflict of interestAll authors declare they have no conflict of interest., (© The Author(s), under exclusive licence to Springer Nature B.V. 2022.)

The purpose of this study is to examine the impact of an online virtual human role-play simulation in teaching high school educators and staff to identify, talk to, and if necessary, refer students in psychological distress to support services. High school educators ( N  = 31,144) from 43 US states and 5 American territories completed a baseline survey and then randomly assigned to a wait-list control or treatment group. Participants in the treatment group completed the training simulation which included active learning strategies to teach evidenced-based communication strategies such as motivational interviewing to build skills and shift attitudes. Immediately after the training, treatment group participants completed a post-survey and then a 3-month follow-up survey. Baseline and post-surveys included the validated gatekeeper behavior scale measures which assess attitudinal constructs that predict helping behaviors. Self-reported helping behaviors were collected at baseline from both groups and at the 3-month follow-up for the treatment group. The treatment group participants' post and follow-up data were compared to the control group's baseline measures. The treatment group post-training scores were significantly higher ( p  < .001) than the control group's baseline scores for all gatekeeper behavior scale attitudinal constructs of preparedness, likelihood, and self-efficacy to engage in helping behaviors. A teacher subsample reported significant increases ( p  < .001) in the number of students referred to mental health support services when compared to baseline measures of the control group. Role-play simulations hold promise in teaching educators to become the "eyes and ears" of student mental health by empowering them to identify students in psychological distress, engage them in effective conversations about their concerns, and if necessary, make a referral to behavioral health support services. Future studies need to implement measures that document students entering counseling as a result of self-reported referrals and examine the impact of the training on the overall mental health culture within schools. Such studies could lead to simulations being widely adopted to support public health initiatives that address student mental health and wellness., Competing Interests: Conflict of InterestWe are reporting that GA and NK have employment agreements with Kognito, the company that developed the simulation used in this study. JM and KS were independent statistical consultants from the University of Georgia who received payment from Kognito for the data analysis. Compensation from Kognito was not tied to study results. There are no other conflicts of interest to declare; thus, we have disclosed those interests fully to JTBS., (© The Author(s) 2022.)

This article introduces a novel approach to the classification of categorical time series under the supervised learning paradigm. To construct meaningful features for categorical time series classification, we consider two relevant quantities: the spectral envelope and its corresponding set of optimal scalings. These quantities characterize oscillatory patterns in a categorical time series as the largest possible power at each frequency, or spectral envelope , obtained by assigning numerical values, or scalings , to categories that optimally emphasize oscillations at each frequency. Our procedure combines these two quantities to produce an interpretable and parsimonious feature-based classifier that can be used to accurately determine group membership for categorical time series. Classification consistency of the proposed method is investigated, and simulation studies are used to demonstrate accuracy in classifying categorical time series with various underlying group structures. Finally, we use the proposed method to explore key differences in oscillatory patterns of sleep stage time series for patients with different sleep disorders and accurately classify patients accordingly. The code for implementing the proposed method is available at https://github.com/zedali16/envsca.

WW is a validated behavioral weight management program that encourages healthy habits. WW developed a method of personalizing the SmartPoints® budget depending on dietary and lifestyle preferences, and participants were placed into one of three plans as a pilot evaluation of this new program. In this 6-month, single-arm pilot study, participants attended weekly workshops and used an app to monitor eating and physical activity. Baseline and 6-month assessments included weight, waist circumference, blood pressure, energy intake, cravings, happiness, health-related quality of life, hunger, and fullness. Of 145 adults assessed at baseline, 126 (87%) provided follow-up data. Pre-post changes showed significant reductions in body weight (7.39% ± 5.93%), calories consumed (24.79% ± 32.35%) and significant improvements in cravings, happiness, all SF-36 scales and hunger but not in fullness. Greater % weight loss was related to greater improvements in happiness (r = .38, p < .001), general health perceptions (r = .29, p = .001), and health change (r = .31, p = .001), and greater reduction in role limitations due to personal or emotional problems (r = .24, p = .01). Greater % reduction in caloric intake was associated with greater reductions in cravings (r = .23, p = .01), as well as with greater improvements in happiness (r = .23, p = .01), physical functioning (r = .23, p = .01), and general health perceptions (r = .23, p = .01). Participants in this modified program achieved significant weight loss, regardless of dietary plan, as well as improvements in a variety of other physical and psychological constructs. Those who achieved greater reductions in weight also reported greater improvements in cravings, happiness and some quality of life measures., (© Society of Behavioral Medicine 2021. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

By 2050, two-thirds of the world's population is expected to be living in cities and towns, a marked increase from today's level of 55 percent. If the general trend is unmistakable, efforts to measure it precisely have been beset with difficulties: the criteria defining urban areas, cities and towns differ from one country to the next and can also change over time for any given country. The past decade has seen great progress toward the long-awaited goal of scientifically comparable urbanization measures, thanks to the combined efforts of multiple disciplines. These efforts have been organized around what is termed the "statistical urbanization" concept, whereby urban areas are defined by population density, contiguity and total population size. Data derived from remote-sensing methods can now supply a variety of spatial proxies for urban areas defined in this way. However, it remains to be understood how such proxies complement, or depart from, meaningful country-specific alternatives. In this paper, we investigate finely resolved population census and satellite-derived data for the United States, Mexico and India, three countries with widely varying conceptions of urban places and long histories of debate and refinement of their national criteria. At the extremes of the urban-rural continuum, we find evidence of generally good agreement between the national and remote sensing-derived measures (albeit with variation by country), but identify significant disagreements in the middle ranges where today's urban policies are often focused., Competing Interests: Conflicts of Interest: The authors declare no conflict of interest.

We apply a three-step sequential procedure to estimate the change-point of count time series. Under certain regularity conditions, the estimator of change-point converges in distribution to the location of the maxima of a two-sided random walk. We derive a closed-form approximating distribution for the maxima of the two-sided random walk based on the invariance principle for the strong mixing processes, so that the statistical inference for the true change-point can be carried out. It is for the first time that such properties are provided for integer-valued time series models. Moreover, we show that the proposed procedure is applicable for the integer-valued autoregressive conditional heteroskedastic (INARCH) models with Poisson or negative binomial conditional distribution. In simulation studies, the proposed procedure is shown to perform well in locating the change-point of INARCH models. And, the procedure is further illustrated with empirical data of weekly robbery counts in two neighborhoods of Baltimore City.

Nitrogen pollution is one of the primary threats to coastal water quality globally, and governmental regulations and marine policy are increasingly requiring nitrogen remediation in management programs. Traditional mitigation strategies (e.g., advanced wastewater treatment) are not always enough to meet reduction goals. Novel opportunities for additional nitrogen reduction are needed to develop a portfolio of long-term solutions. Increasingly, in situ nitrogen reduction practices are providing a complementary management approach to the traditional source control and treatment, including recognition of potential contributions of coastal bivalve shellfish. While policy interest in bivalves has focused primarily on nitrogen removal via biomass harvest, bivalves can also contribute to nitrogen removal by enhancing denitrification (the microbial driven process of bioavailable nitrogen transformation to di-nitrogen gas). Recent evidence suggests that nitrogen removed via enhanced denitrification may eclipse nitrogen removal through biomass harvest alone. With a few exceptions, bivalve-enhanced denitrification has yet to be incorporated into water quality policy. Here, we focus on oysters in considering how this issue may be addressed. We discuss policy options to support expansion of oyster-mediated denitrification, describe the practical considerations for incorporation into nitrogen management, and summarize the current state of the field in accounting for denitrification in oyster habitats. When considered against alternative nitrogen control strategies, we argue that enhanced denitrification associated with oysters should be included in a full suite of nitrogen removal strategies, but with the recognition that denitrification associated with oyster habitats will not alone solve our excess nitrogen loading problem.

Objective: To re-evaluate the effect of Medicaid on poverty using a poverty measure that accounts for health insurance needs and benefits and an evaluation approach that reflects disparities in access to alternative coverage., Data Sources: The Current Population Survey (CPS) for calendar year 2015., Study Design: We estimate the effect of losing Medicaid on poverty, combining two previous approaches: (1) A propensity impact, which simulates a no-Medicaid counterfactual incorporating changes to health insurance and medical out-of-pocket spending, using the Supplemental Poverty Measure (SPM). This measure does not reflect a need for health care access nor how health benefits meet that need. (2) An accounting impact, which assumes that those losing Medicaid remain uninsured and does not incorporate any behavioral changes, using the health-inclusive poverty measure (HIPM). This measure includes a need for health insurance in the threshold and health insurance benefits in resources., Data Collection/extraction Methods: Not applicable., Principal Findings: Using the propensity-matched approach, we attributed a 2.5 percentage point reduction in health-inclusive poverty among those younger than age 65 to the Medicaid program, between the 1.0-point SPM propensity-match impact and the 3.9-point HIPM accounting impact. Medicaid's antipoverty impact and HIPM-SPM differences are greater among those who would become uninsured. HIPM propensity-matched estimates reveal much larger impacts of Medicaid on poverty disparities linked to race/ethnicity and single parenthood than SPM-based propensity estimates., Conclusions: Both the poverty measure and the method used to estimate the counterfactual make substantial, policy-relevant differences to estimates of Medicaid's impact on poverty. A poverty measure that fails to incorporate health insurance needs and benefits substantially underestimates Medicaid's effect. Failing to consider adjustments in insurance coverage and out-of-pocket spending substantially overestimates Medicaid's effect and underestimates its reduction of disparities., (© 2021 Health Research and Educational Trust.)

Here, we report the implementation and application of a simple, structure-aware framework to generate target-specific screening libraries. Our approach combines advances in generative artificial intelligence (AI) with conventional molecular docking to explore chemical space conditioned on the unique physicochemical properties of the active site of a biomolecular target. As a demonstration, we used our framework, which we refer to as sample-and-dock, to construct focused libraries for cyclin-dependent kinase type-2 (CDK2) and the active site of the main protease (M pro ) of the SARS-CoV-2 virus. We envision that the sample-and-dock framework could be used to generate theoretical maps of the chemical space specific to a given target and so provide information about its molecular recognition characteristics.

Recently, interest has grown in using oyster-mediated denitrification resulting from aquaculture and restoration as mechanisms for reactive nitrogen (N) removal. To date, short-term N removal through bioextraction has received the most management interest, but there is a growing body of research that has shown oysters can also mediate the long-term removal of N through denitrification (the microbial conversion of reactive N to relatively inert dinitrogen (N 2 ) gas). Oyster suspension feeding and ammonium release via waste and deposition of organic matter to the sediments can stimulate nitrification-denitrification near oyster reefs and aquaculture sites. Oysters also harbor a diverse microbial community in their tissue and shell promoting denitrification and thus enhanced N removal. Additionally, surface areas on oyster reefs provide a habitat for other filter-feeding macrofaunal communities that can further enhance denitrification. Denitrification is a complex biogeochemical process that can be difficult to convey to stakeholders. These complexities have limited consideration and inclusion of oyster-mediated denitrification within nutrient management. Although oyster-mediated denitrification will not be a standalone solution to excess N loading, it may provide an additional management tool that can leverage oyster aquaculture and habitat restoration as a N mitigation strategy. Here, we provide an overview of the biogeochemical processes involved in oyster-mediated denitrification and summarize how it could be incorporated into nutrient management efforts by various stakeholders.

Studying spin-momentum correlations in hadronic collisions offers a glimpse into a three-dimensional picture of proton structure. The transverse single-spin asymmetry for midrapidity isolated direct photons in p^{↑}+p collisions at sqrt[s]=200  GeV is measured with the PHENIX detector at the Relativistic Heavy Ion Collider (RHIC). Because direct photons in particular are produced from the hard scattering and do not interact via the strong force, this measurement is a clean probe of initial-state spin-momentum correlations inside the proton and is in particular sensitive to gluon interference effects within the proton. This is the first time direct photons have been used as a probe of spin-momentum correlations at RHIC. The uncertainties on the results are a 50-fold improvement with respect to those of the one prior measurement for the same observable, from the Fermilab E704 experiment. These results constrain gluon spin-momentum correlations in transversely polarized protons.

Competing Interests: We declare no competing interests.

In the U.S., human papillomavirus (HPV) vaccination has been recommended for individuals up to age 26, although the vaccination is currently approved for all people up to the age of 45. This research sought to explore HPV vaccination disparities by age with subgroup analysis by gender identity and sexual orientation groups, as well as sociodemographic factors that may serve as barriers to or facilitators of vaccination. This study used data from the 2018 Behavioral Risk Factor Surveillance System. Only data for individuals who reported their gender identity, sexual orientation, and HPV vaccination status were included in the analytic sample (n = 7330). HPV vaccination rates for this sample were low, as only 18.2% (n = 1332) of the sample had received the HPV vaccination. These low rates of vaccination were similar across all subsamples: cisgender men (9.8%, n = 343), cisgender women (25.8%, n = 985), heterosexuals (17.5%, n = 1197), lesbian women or gay men (20.8%, n = 40), and bisexuals (30.8%, n = 95). In multivariable logistic regression models, younger participants (18-34) were more likely to report receiving the HPV vaccination across all subsamples. Further modeling indicated several common factors associated with higher odds of vaccination: living in a metropolitan area, having insurance coverage, and having at least one provider. Understanding vaccination disparities, as well as vaccination facilitators and barriers, is important to inform policy and program efforts. This is especially significant for adults between the ages of 35 and 44 who were excluded from the initial vaccination recommendations but are vulnerable due to changing cultural norms, including delayed marriage, nonmonogamous long-term relationships, and the ending of long-term partnerships., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC part of Springer Nature.)

During the COVID-19 pandemic, individuals were advised to adhere to social distancing guidelines limiting physical interpersonal contact. Humans have a suite of adaptations to satisfy belonging needs while avoiding diseased conspecifics. Competition between motivational systems may explain adherence and resistance to social distancing guidelines and how technologically mediated interactions further shape these decisions. This study is a preregistered analysis of data in a representative sample collected during the pandemic investigating how individual differences in affiliative and pathogen-avoidant motives predict interest in physical interactions ( N  = 2409). Germ aversion predicted disinterest in physical interactions and need to belong predicted interest. Additional analyses revealed technology use satisfied belonging motives that unexpectedly heightened interest in physical contact. Exploratory analyses further indicate that internet speed was similarly associated with greater interest in physical interactions. We frame these results through a competing fundamental social motives framework and discuss how to address future pandemics effectively., (© 2021 Elsevier Ltd. All rights reserved.)

Background: US nursing homes are required to follow Centers for Disease Control guidance for COVID-19 transmission-based precautions (TBP) when admitting COVID-positive patients., Objective: To assess how frequently nursing homes had shortages of personal protective equipment (PPE) or staffing in weeks when they admitted COVID-positive patients, which likely made it more difficult to follow TBP, and to compare facility characteristics by admissions practices., Design and Setting: Facility-level data from the Nursing Home COVID-19 Public File for the period between June 7, 2020 and March 7, 2021 was combined with additional data. The percentages of nursing homes that admitted COVID-positive patients and that had shortages when admitting were calculated for each week. Descriptive statistics and logistic regression models were used to examine the relationship between facility characteristics and the likelihood of admitting COVID-positive patients., Measurements: Facilities were categorized as having admitted COVID-positive patients in a week if one or more admissions requiring TBP were reported for that week. Facilities that reported having less than a 1-week supply of any type of PPE or being short any type of staff in a week were defined, respectively, as having a PPE shortage or staffing shortage in that week., Results: Over the 40-week study period, 39% of US nursing homes admitted COVID-positive patients in at least 1 week in which they were experiencing PPE or staffing shortages. Facilities that admitted COVID-positive patients with shortages generally had lower Centers for Medicare and Medicaid Services overall five-star ratings than other facilities. Only a small percentage of facilities that admitted COVID-positive patients while facing shortages were located in counties with severe shortages of PPE or staffing. In logistic regression models, shortages were not associated with COVID-positive admissions., Conclusion: The widespread practice of admitting COVID-positive patients while facing shortages may have put nursing home residents and staff at heightened risk of COVID-19 infection., (© 2021 The American Geriatrics Society.)

We reinvestigate a simple model used in the literature concerning the thermodynamic analysis of protein cold denaturation. We derive an exact thermodynamic expression for cold denaturation and give a better approximation than exists in the literature for predicting cold denaturation temperatures in the two-state model. We discuss the "dark-side" implications of this work for previous temperature-dependent protein dynamics experiments and discuss microfluidic experimental technologies, which could explore the thermal stability range of proteins below the bulk freezing point of water.

Objective: Attitudes and beliefs related to immersion in military culture can affect postseparation transition to the civilian setting. The etiology and complexity of these reactions are often overlooked by mental health providers, which can result in negative consequences for treatment. This qualitative study examined veterans' perceptions of military culture and the impact of military service on veterans' values, beliefs, and behaviors. The goal of this research was to identify aspects of military culture that are important for health care providers to consider as they care for veterans and to inform culturally sensitive mental health care for veterans., Method: Fifty-two military veterans completed a self-report survey and participated in semistructured focus groups., Results: Participants reported diverse military experiences, and many endorsed a high level of continuing identification with aspects of military culture. Seven broad themes related to military culture emerged from qualitative analyses: (a) military values, beliefs, and behaviors; (b) relationships; (c) occupational habits and practices; (d) acquired skills; (e) communication; (f) affiliation; and (g) psychological health and well-being., Conclusion: This thematic analysis elucidated strategies to improve mental health services for veterans, using a nuanced model that encourages providers to better distinguish aspects of cultural transition from psychopathology. Results underscored the importance of training mental health providers to ensure sensitivity to military culture. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

We develop an agent-based model on a network meant to capture features unique to COVID-19 spread through a small residential college. We find that a safe reopening requires strong policy from administrators combined with cautious behavior from students. Strong policy includes weekly screening tests with quick turnaround and halving the campus population. Cautious behavior from students means wearing facemasks, socializing less, and showing up for COVID-19 testing. We also find that comprehensive testing and facemasks are the most effective single interventions, building closures can lead to infection spikes in other areas depending on student behavior, and faster return of test results significantly reduces total infections., Competing Interests: The authors have declared that no competing interests exist.

Intimate Partner Violence (IPV) is an understudied health problem among young gay, bisexual, and other non-identified young men who have sex with men (YMSM). According to cross-sectional studies, IPV is associated with psychosocial and mental health problems, such as stigma and depression, among YMSM. IPV is also associated with health-risk behaviors, such as substance use, among this population. Yet, to date, no studies have used longitudinal data to examine determinants of IPV among YMSM. This gap in the extant literature is problematic, as it limits our understanding of how to intervene to interrupt cycles of violence. The aim of the present study was to examine longitudinal determinants of IPV among a sample of (N = 526) YMSM living in the New York City area. Longitudinal analyses using Generalized Estimating Equations (GEE) were used to examine individual, relationship, mental health, psychosocial, and substance use factors in relation to IPV victimization and perpetration. Most notably, early experiences of IPV were a robust predictor of later experiences of IPV victimization and perpetration. Relationship status, depression, public gay-related stigma, and illicit substance use were associated with IPV victimization over time. Similarly, relationship status, depression, public gay-related stigma, marijuana, and other illicit substance were associated with IPV perpetration. These findings suggest that prevention programs and awareness campaigns should aim to reach YMSM before their first experiences of relationship violence, as these early experiences of violence are strongly linked to later experiences of violence. Also, IPV interventions should be tailored to the needs of YMSM and should target depressive symptoms, gay-related stigma, and substance use behaviors. Additionally, substance use interventions may be improved by addressing IPV. Finally, policymakers should support policies that improve the social climate for LGBTQ people, thereby reducing gay-related stigma, and potentially stemming violence against and among YMSM.

Background: High adolescent gun-related mortality, gun violence, pro-gun policies, white supremacy, and the long-term socioeconomic and other effects of racial oppression are intricately linked in the United States. Racist prejudice depicts male individuals of color as more prone to criminality than white male individuals. We described long-term patterns of weapon carrying in US schools among non-Hispanic (NH) white, NH Black/African American, and Hispanic boys, hypothesizing that in contrast to racist stereotypes, boys of color did not bring weapons into schools more often than NH white boys in recent years., Methods: We conducted a time series analysis using 1993-2019 Youth Risk Behavior Surveillance System data comparing boys' self-reported weapon carrying in a nationally representative sample of US high schools by race and/or ethnicity, age, and self-reported experience of safety and violence at school., Results: Weapon carrying in schools has declined among all boys. Comparing all schools, we found no significant differences in weapon carrying (4%-5%) by race and/or ethnicity in 2017 and 2019. Boys who reported experiencing violence or feeling unsafe at school were at least twice as likely to bring a weapon into school, and such negative experiences were more common among boys of color (8%-12%) than among NH white boys (4%-5%). In schools perceived as safer, NH white boys have been more likely to bring weapons into schools than NH Black/African American or Hispanic boys in the past 20 years., Conclusions: Our findings contradict racist prejudice with regard to weapon carrying in schools, particularly in more favorable school environments. Making schools safer may reduce weapon carrying in schools where weapon carrying is most common., Competing Interests: POTENTIAL CONFLICT OF INTEREST: The authors have indicated they have no potential conflicts of interest to disclose., (Copyright © 2021 by the American Academy of Pediatrics.)

The French chemist Louis Pasteur (1822-1895) chose to be actively engaged in the fine arts throughout his life-yet scholarship has ignored or dismissed these pursuits. This empirical study documents his unknown, but deep involvement with art and artists from age thirteen until his death. This was no casual pastime. Art animated Pasteur. It was also at times useful to him for making political statements, cultivating status, and supporting loyal friends. This account identifies nearly twenty significant friendships with painters and sculptors and uncovers over thirty other artists with whom his associations deserve examination. The narrative suggests points at which art was especially germane to his scientific career and possible junctures that merit further research. Evidence from his artistic friendships also corrects the common picture of Pasteur as a dour workaholic who never laughed or smiled.

Hamstring muscle function during knee flexion has been linked to hamstring injury and performance. However, it is unclear whether knee flexion alone (KF) requires similar hamstring electromyography (EMG) activity pattern to simultaneous hip extension and knee flexion (HE-KF), a combination that occurs in the late swing phase of sprinting. This study examined whether HE-KF maximal voluntary isometric contraction (MVIC) evokes higher (EMG) activity in biceps femoris long head (BFlh) and semitendinosus (ST) than KF alone. Effects of shank rotation angles were also tested. Twenty-one males performed the above-mentioned MVICs while EMG activity was measured along ST and BFlh. Conditions were compared using a one-way mixed functional ANOVA model under a fully Bayesian framework. Higher EMG activity was found in HE-KF in all shank rotation positions than in KF in the middle region of BFlh (highest in the 9th channel, by 0.022 mV [95%CrI 0.014 to 0.030] in neutral shank position). For ST, this was only observed in the neutral shank position and in the most proximal channel (by 0.013 mV [95%CrI 0.001 to 0.025]). We observed muscle- and region-specific responses to HE-KF. Future studies should examine whether hamstring activation in this task is related to injury risk and sprint performance., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Background: The study objective was to examine cat owner ectoparasiticide purchases in the United States and estimate the impact of purchase gaps on timely ectoparasite protection administration. These purchase gaps lead to periods of time when cats are unprotected from ectoparasites., Methods: Ectoparasiticide purchase transactions for individual cats from 671 U.S. veterinary clinics from January 1, 2017 through June 30, 2019 were evaluated to determine time "gaps" between doses of ectoparasiticides purchased in a defined 12-month period. Ectoparasiticides examined were topically applied products that contained fluralaner, fipronil/(S)-methoprene/pyriproxyfen, imidacloprid/pyriproxyfen or selamectin as active ingredients. The duration of protection following administration of one dose was 8-12 weeks for the fluralaner-containing product and one month for the other products., Results: Ectoparasiticide purchase records were obtained from 114,853 cat owners and analysis found that most owners bought ≤ 6 months of protection during the year, with 61-75% (depending on the product) purchasing just 1-3 months of protection. The size of the average purchase gap was determined for all dose combinations out to 12 months of protection (5-7 doses for fluralaner and 12 doses for the other three products dosed monthly. The largest gaps occurred between the first and second doses and the second and third doses. Average purchase gaps for the four different products between doses 1 and 2 ranged from 11.2 to 13.9 weeks and between doses 2 and 3 ranged from 7.7 to 12.2 weeks. The fraction of purchases separated by gaps and the average length of the gap tended to decrease with increasing number of doses purchased. Owners purchasing the 8 to 12-week duration product containing fluralaner provided ectoparasite protection ("doses plus gap period") for a larger proportion of each 2-dose period compared with owners purchasing products administered monthly., Conclusions: When cat owners purchase flea and tick medication, gaps between subsequent purchases reduces the proportion of time ectoparasite protection can be provided. The duration of the gap between doses has an impact on the effectiveness of flea/tick medication because it inserts a period without flea and tick protection between doses of flea and tick medication. The gaps between purchases were shorter and the period of ectoparasite protection was larger for owners purchasing a 12-week product than for owners purchasing a monthly product.

Behavioral studies have shown that statistical properties of object groups are perceived accurately with brief exposure durations. This finding motivated the hypothesis that ensemble perception occurs rapidly in vision. However, the precise timing of ensemble perception remains unclear. Here, we used the superior temporal resolution of electroencephalography to directly compare the timing of ensemble processing to that of individual object processing. The P3b was chosen as a particular component of interest, as it is thought to measure the latency of stimulus evaluation. Participants performed a simple "oddball" task in which sets of 51 lines with varied orientations sequentially flashed briefly on the display. In these sequences, there was a 20% chance of an individual oddball, wherein one marked object tilted clockwise, and a 20% chance of an ensemble oddball, wherein the average orientation of the set tilted clockwise. In counterbalanced blocks, participants were instructed to respond to either individual or ensemble oddballs. ERP analysis was performed to test the timing of this processing. At parietal electrodes, P3b components were found for both individual and ensemble oddballs. Ensemble P3b components were found to occur significantly earlier than individual P3b components, as measured with both 50% area latency and 50% onset latency. Using multivariate pattern analysis, ensemble oddball trials were classifiable from standard trials significantly earlier in their timecourse than individual oddball trials. Altogether, these results provide compelling evidence that ensemble perception occurs rapidly and that ensemble properties can be available earlier than individual object properties., (© 2021 Massachusetts Institute of Technology.)

This paper analyzes variable social identity construction for my Dad over his last two years, within his family, and then within several institutions, before he died of Alzheimer's Disease (AD). This article makes epistemic and methodological contributions to research on persons with AD by using analytic autoethnography and long-term ethnographic case development to trace processes by which my Dad's evolving social identity was constructed -- and increasingly socially constructed -- as his memory became more impaired and he moved from home into several institutions. It analyzes how our family resisted his conversion into an "AD patient" - the stigmatized sum of his symptoms - but engaged in what felt like Goffmanian betrayals to care for him. The paper recognizes the value and need to fight the image of AD as social death in research, the medical system, and popular understanding, but proposes a family Memory-Relationship self to conceptually capture the trauma many families feel as AD increasingly impairs the loved one with AD and leads to their death (unless they die of something else first). My Dad's placement in five institutions in six months created awful natural experiment-like leverage, because he was alternatively constructed in institutions as a legally competent adult, a dangerous patient, and an AD patient, and often responded correspondingly., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Tolerance intervals provide a bracket intended to contain a percentage (e.g., 80%) of a population distribution given sample estimates of the mean and variance. In random-effects meta-analysis, tolerance intervals should contain researcher-specified proportions of underlying population effect sizes. Using Monte Carlo simulation, we investigated the coverage for five relevant tolerance interval estimators: the Schmidt-Hunter credibility intervals, a prediction interval, two content tolerance intervals adapted to meta-analysis, and a bootstrap tolerance interval. None of the intervals contained the desired percentage of coverage at the nominal rates in all conditions. However, the prediction worked well unless the number of primary studies was small (<30), and one of the content tolerance intervals approached nominal levels with small numbers (<20) of primary studies. The bootstrap tolerance interval achieved near nominal coverage if there were sufficient numbers of primary studies (30+) and large enough sample sizes (N ≅ 70) in the included primary studies, although it slightly exceeded nominal coverage with large numbers of large-sample primary studies. Next, we showed the results of applying the intervals to real data using a set of previously published analyses and provided suggestions for practice. Tolerance intervals incorporate error of estimation into the construction of proper brackets for fractions of population true effects. In many contexts, such intervals approach the desired nominal levels of coverage., (© 2021 John Wiley & Sons, Ltd.)

Age of sexual debut is a critical health indicator for young sexual minority men (YSMM), associated with an increased likelihood of HIV acquisition, use of alcohol, tobacco, and other substances, and psychological distress. This study examined the age of same-sex sexual debut for five sexual behaviors in a sample of racially/ethnically and socioeconomically diverse gay-identified YSMM in New York City. The mean age of sexual debut of any behavior was 14.5 years old and 19% of the sample reported sexual debut prior to age 13. Overall, mutual masturbation occurred at the youngest mean age, followed by performed oral, received oral, receptive anal, and insertive anal intercourse. There were significant differences by race/ethnicity and perceived familial socioeconomic status (SES), such that Black and Hispanic/Latino men had earlier ages of debut for performed oral and receptive and insertive anal sex, while upper SES men had later ages of debut for receptive and insertive anal intercourse. These findings are relevant to trends in HIV incidence in the U.S., which are highest among Black and Hispanic/Latino YSMM and may be associated with earlier age of sexual debut. These findings also underscore a need for comprehensive and inclusive sex education at younger ages.

We show that the temperature at which foods and beverages are served impacts consumers' complementary purchases, defined as additional foods and beverages purchased for a consumption episode. Across a series of studies, including field studies and controlled laboratory experiments, we show that consumers choose more complementary food items when they consume or intend to consume a food or beverage served cold rather than hot. This occurs because cold consumables are expected to be less satiating compared to hot consumables. Serving temperatures that increase complementary purchasing may enhance the firm's bottom line, but could add unnecessary calories to the meal, and thus is of interest to both consumers and managers., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Consensual non-monogamous (CNM) relationship rules, the boundaries and understandings partners have about acceptable behaviors related to their CNM relationship, are associated with relationship functioning and sexual health risk among gay and bisexual men. Partnered young gay and bisexual men (YGBM) experience unique relational challenges and sexual health disparities. Thus, understanding the nuances of relationship rules among YGBM in CNM relationships is of particular importance. However, few studies have examined relationship rules specifically among YGBM. The current study sought to explore relationship rules among YGBM in CNM relationships, including both those explicitly discussed and those implicitly assumed. We also assessed concordance and discrepancies in partners' reports of their relationship rules, as well as rule violations. Partners from 10 CNM couples (n = 20; M age  = 25.3) completed separate semi-structured interviews that included questions about their relationship rules. Individual- and dyad-level analyses were conducted using a modified version of the consensual qualitative research method. Three main themes of relationship rules emerged from the data: extradyadic partner criteria, conditions regarding extradyadic sex, and conditions regarding maintenance of the primary relationship. While 39% of participants reported rules that were not endorsed by their partner, few clearly contradictory discrepancies in partners' reports were observed. Nine participants reported having at least one implicit rule and 70% of participants (from 8 of 10 couples) reported that they and/or their partner violated at least one rule. Explicit rules and rule concordance may be associated with improved relationship functioning. Common violations of sexual risk reduction rules may contribute to YGBM's increased HIV/STI risk.

Objective: Patient trust in health care providers is associated with better health behaviors and utilization, yet provider trust has not been consistently conceptualized. This study uses qualitative methods to identify the key health provider behaviors that patients report build their trust, and data from a national U.S. survey of adults to test the robustness of the qualitative findings., Methods: In this mixed methods study, we conducted 40 semi-structured interviews with a diverse sample to identify the provider behaviors that build trust. We then analyzed a nationally representative survey (n = 6,517) to examine the relationship between respondents' trust in their usual provider and the key trust-related behaviors identified in the qualitative interviews., Results: Interviewees reported that health providers build trust by communicating effectively (listening and providing detailed explanations), caring about their patients (treating them as individuals, valuing their experience, and showing commitment to solving their health issues), and demonstrating competence (being knowledgeable, thorough, and solving their health issues). Trust in one's provider was highly correlated with all eight survey items measuring communication, caring, and competence., Conclusions: To build trust with patients, health providers should actively listen, provide detailed explanations, show caring for patients, and demonstrate their knowledge., Competing Interests: Declaration of Competing Interest The authors report no declarations of interest., (Copyright © 2020. Published by Elsevier B.V.)

Competing Interests: Competing interests: None declared.

Background: Substance use places a substantial burden on our communities, both economically and socially. In light of COVID-19, it is predicted that as many as 75,000 more people will die from alcohol and other substance use and suicide as a result of isolation, new mental health concerns, and various other stressors related to the pandemic. Public awareness campaigns that aim to destigmatize substance use and help individuals have meaningful conversations with friends, coworkers, or family members to address substance use concerns are a timely and cost-effective means of augmenting existing behavioral health efforts related to substance use. These types of interventions can supplement the work being done by existing public health initiatives., Objective: This pilot study examines the impact of the One Degree: Shift the Influence role play simulation, designed to teach family, friends, and coworkers to effectively manage problem-solving conversations with individuals that they are concerned about regarding substance use., Methods: Participants recruited for this mixed methods study completed a presurvey, the simulation, and a postsurvey, and were sent a 6-week follow-up survey. The simulation involves practicing a role play conversation with a virtual human coded with emotions, a memory, and a personality. A virtual coach provides feedback in using evidence-based communication strategies such as motivational interviewing., Results: A matched sample analysis of variance revealed significant increases at follow-up in composite attitudinal constructs of preparedness (P<.001) and self-efficacy (P=.01), including starting a conversation with someone regarding substance use, avoiding upsetting someone while bringing up concerns, focusing on observable facts, and problem solving. Qualitative data provided further evidence of the simulation's positive impact on the ability to have meaningful conversations about substance use., Conclusions: This study provides preliminary evidence that conversation-based simulations like One Degree: Shift the Influence that use role play practice can teach individuals to use evidence-based communication strategies and can cost-effectively reach geographically dispersed populations to support public health initiatives for primary prevention., (©Glenn Albright, Nikita Khalid, Kristen Shockley, Kelsey Robinson, Kevin Hughes, Bethany Pace-Danley. Originally published in JMIR Formative Research (https://formative.jmir.org), 29.04.2021.)

Urban tree cover provides benefits to human health and well-being, but previous studies suggest that tree cover is often inequitably distributed. Here, we use National Agriculture Imagery Program digital ortho photographs to survey the tree cover inequality for Census blocks in US large urbanized areas, home to 167 million people across 5,723 municipalities and other Census-designated places. We compared tree cover to summer land surface temperature, as measured using Landsat imagery. In 92% of the urbanized areas surveyed, low-income blocks have less tree cover than high-income blocks. On average, low-income blocks have 15.2% less tree cover and are 1.5⁰C hotter than high-income blocks. The greatest difference between low- and high-income blocks was found in urbanized areas in the Northeast of the United States, where low-income blocks in some urbanized areas have 30% less tree cover and are 4.0⁰C hotter. Even after controlling for population density and built-up intensity, the positive association between income and tree cover is significant, as is the positive association between proportion non-Hispanic white and tree cover. We estimate, after controlling for population density, that low-income blocks have 62 million fewer trees than high-income blocks, equal to a compensatory value of $56 billion ($1,349/person). An investment in tree planting and natural regeneration of $17.6 billion would be needed to close the tree cover disparity, benefitting 42 million people in low-income blocks., Competing Interests: The authors have declared that no competing interests exist.

Zwitterionic polymers have extraordinary properties, that is, significant hydration and the so-called antipolyelectrolyte effect, which make them suitable for biomedical applications. The hydration induces an antifouling effect, and this has been investigated significantly. The antipolyelectrolyte effect refers to the extraordinary ion-responsive behavior of particular polymers that swell and hydrate considerably in physiological solutions. This actuation begins to attract attention to achieve in vivo antifouling that is challenging for general polyelectrolytes. In this study, we established the sophisticated cornerstone of the antipolyelectrolyte effect in detail, including (i) the essential parameters, (ii) experimental verifications, and (iii) effect of improving antifouling performance. First, we find that both osmotic force and charge screening are essential factors. Second, we identify the antipolyelectrolyte effect by visualizing the swelling and hydration dynamics. Finally, we verify that the antifouling performance can be enhanced by exploiting the antipolyelectrolyte effect and report reduction of 85% and 80% in ex and in vivo biofilm formation, respectively.

This article introduces a flexible nonparametric approach for analyzing the association between covariates and power spectra of multivariate time series observed across multiple subjects, which we refer to as multivariate conditional adaptive Bayesian power spectrum analysis (MultiCABS). The proposed procedure adaptively collects time series with similar covariate values into an unknown number of groups and nonparametrically estimates group-specific power spectra through penalized splines. A fully Bayesian framework is developed in which the number of groups and the covariate partition defining the groups are random and fit using Markov chain Monte Carlo techniques. MultiCABS offers accurate estimation and inference on power spectra of multivariate time series with both smooth and abrupt dynamics across covariate by averaging over the distribution of covariate partitions. Performance of the proposed method compared with existing methods is evaluated in simulation studies. The proposed methodology is used to analyze the association between fear of falling and power spectra of center-of-pressure trajectories of postural control while standing in people with Parkinson's disease., (© 2021 John Wiley & Sons, Ltd.)

Understanding the genetic causes of evolutionary diversification is challenging because differences across species are complex, often involving many genes. However, cases where single or few genetic loci affect a trait that varies dramatically across a radiation of species provide tractable opportunities to understand the genetics of diversification. Here, we begin to explore how diversification of bioluminescent signals across species of cypridinid ostracods ("sea fireflies") was influenced by evolution of a single gene, cypridinid-luciferase. In addition to emission spectra ("colour") of bioluminescence from 21 cypridinid species, we report 13 new c-luciferase genes from de novo transcriptomes, including in vitro assays to confirm function of four of those genes. Our comparative analyses suggest some amino acid sites in c-luciferase evolved under episodic diversifying selection and may be associated with changes in both enzyme kinetics and colour, two enzymatic functions that directly impact the phenotype of bioluminescent signals. The analyses also suggest multiple other amino acid positions in c-luciferase evolved neutrally or under purifying selection, and may have impacted the variation of colour of bioluminescent signals across genera. Previous mutagenesis studies at candidate sites show epistatic interactions, which could constrain the evolution of c-luciferase function. This work provides important steps toward understanding the genetic basis of diversification of behavioural signals across multiple species, suggesting different evolutionary processes act at different times during a radiation of species. These results set the stage for additional mutagenesis studies that could explicitly link selection, drift, and constraint to the evolution of phenotypic diversification., (© 2020 John Wiley & Sons Ltd.)

Supply chain viability (SCV) is an emerging concept of growing importance in operations management. This paper aims to conceptualize, develop, and validate a measurement scale for SCV. SCV is first defined and operationalized as a construct, followed by content validation and item measure development. Data have been collected through three independent samplings comprising a total of 558 respondents. Both exploratory and confirmatory factor analyses are used in a step-wise manner for scale development. Reliability and validity are evaluated. A nomological model is theorized and tested to evaluate nomological validity. For the first time, our study frames SCV as a novel and distinct construct. The findings show that SCV is a hierarchical and multidimensional construct, reflected in organizational structures, organizational resources, dynamic design capabilities, and operational aspects. The findings reveal that a central characteristic of SCV is the dynamic reconfiguration of SC structures in an adaptive manner to ensure survival in the long-term perspective. This research conceptualizes and provides specific, validated dimensions and item measures for SCV. Practitioner directed guidance and suggestions are offered for improving SCV during the COVID-19 pandemic and future severe disruptions., (© The Author(s) 2021.)

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.

The empirical study of belief is emerging at a rapid clip, uniting work from all corners of cognitive science. Reliance on belief in understanding and predicting behavior is widespread. Examples can be found, inter alia, in the placebo, attribution theory, theory of mind, and comparative psychological literatures. Research on belief also provides evidence for robust generalizations, including about how we fix, store, and change our beliefs. Evidence supports the existence of a Spinozan system of belief fixation: one that is automatic and independent of belief rejection. Independent research supports the existence of a system of fragmented belief storage: one that relies on large numbers of causally isolated, context-sensitive stores of belief in memory. Finally, empirical and observational data support at least two systems of belief change. One system adheres, mostly, to epistemological norms of updating; the other, the psychological immune system, functions to guard our most centrally held beliefs from potential inconsistency with newly formed beliefs. Refining our understanding of these systems can shed light on pressing real-world issues, such as how fake news, propaganda, and brainwashing exploit our psychology of belief, and how best to construct our modern informational world. This article is categorized under: Psychology > Reasoning and Decision Making Philosophy > Knowledge and Belief Philosophy > Foundations of Cognitive Science., (© 2020 Wiley Periodicals LLC.)

Eastern New York State is frequently the site of Colorado potato beetle (Leptinotarsa decemlineata, Say) populations with the highest observed levels of insecticide resistance to a range of active ingredients. The dominance of a resistant phenotype will affect its rate of increase and the potential for management. On organic farms on Long Island, L. decemlineata evolved high levels of resistance to spinosad in a short period of time and that resistance has spread across the eastern part of the Island. Resistance has also emerged in other parts of the country as well. To clarify the level of dominance or recessiveness of spinosad resistance in different parts of the United States and how resistance differs in separate beetle populations, we sampled in 2010 beetle populations from Maine, Michigan, and Long Island. In addition, a highly resistant Long Island population was assessed in 2012. All populations were hybridized with a laboratory-susceptible strain to determine dominance. None of the populations sampled in 2010 were significantly different from additive resistance, but the Long Island population sampled in 2012 was not significantly different from fully recessive. Recessive inheritance of high-level resistance may help manage its increase., (© The Author(s) 2020. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Given the high concentration of COVID-19 cases in long-term care (LTC) facilities in the United States, individuals working in these facilities are at heightened risk of SARS-CoV-2 exposure. Using data from the nationally-representative 2017 and 2018 National Health Interview Surveys on adults who reported working in LTC facilities, this study examines the extent to which LTC workers are also at increased risk or potentially at increased risk for severe illness from COVID-19 including hospitalization, intubation, or death. We used the Centers for Disease Control and Prevention's list of conditions placing individuals in these risk categories to the extent possible. We also examined the sociodemographic characteristics of LTC workers by occupation and COVID-19 illness severity risk status. One percent (552 out of 52,159) of the weighted NHIS sample worked in LTC facilities. Workers in LTC facilities were disproportionately Black, female, and low income. Half of LTC workers (50%) were at increased risk of severe illness from COVID-19 and another 19.6% were potentially at increased risk. There were few significant differences in demographic characteristics between risk groups, though those at increased risk had lower educational attainment and recent trouble affording prescription medications. Despite the high degree of vulnerability of both LTC residents and workers to severe illness from COVID-19, many LTC facilities still have inadequate supplies of personal protective equipment and COVID-19 tests. Given that state budget deficits due to the COVID-19 pandemic limit the potential for state actions, enhanced federal efforts are needed to protect LTC residents and staff from COVID-19., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Microplastics which are gradually and randomly decompose into small fragment by exposure of physical and biological external stress are emerging as a significant threat to the all the environments. Here, we have demonstrated the in vitro toxicity of microplastics of two different shapes. To minimize the chemical effect, polyethylene (PE), was used. PE microplastics with two different shapes were prepared, high-density PE microbeads and irregularly ground low-density PE from bulk pellets. It is hypothesized that morphological characteristics and concentration of PE microplastics could affect cellular viability, immunity, and lysis. To quantify the randomness of the microplastic shape, the edge patterns of the generated PE microplastics were converted into numerical values and analyzed using a statistical method. A 10-fold difference in curvature value was observed between microbeads and ground microfragments. To correlate shape differences to toxicology, cells were exposed to PE microplastics on the demand of toxicology studies. We found that the higher concentration and rough structure were associated with the toxicity of plastics toward cells, pro-inflammatory cytokine release, and hemolysis, even though PE is buoyant onto medium. The PE microbeads did not exhibit severe cytotoxicity at any of the tested concentrations, but induced immune and hemolysis responses at high concentrations. When comparing the toxicity of different shapes of PE microplastics, we confirmed by statistical analysis that irregular-shape plastics with sharp edges and higher curvature differences may adversely affect cells, further having possibility to human toxicity in real environment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020. Published by Elsevier B.V.)

This article introduces a nonparametric approach to spectral analysis of a high-dimensional multivariate nonstationary time series. The procedure is based on a novel frequency-domain factor model that provides a flexible yet parsimonious representation of spectral matrices from a large number of simultaneously observed time series. Real and imaginary parts of the factor loading matrices are modeled independently using a prior that is formulated from the tensor product of penalized splines and multiplicative gamma process shrinkage priors, allowing for infinitely many factors with loadings increasingly shrunk towards zero as the column index increases. Formulated in a fully Bayesian framework, the time series is adaptively partitioned into approximately stationary segments, where both the number and locations of partition points are assumed unknown. Stochastic approximation Monte Carlo (SAMC) techniques are used to accommodate the unknown number of segments, and a conditional Whittle likelihood-based Gibbs sampler is developed for efficient sampling within segments. By averaging over the distribution of partitions, the proposed method can approximate both abrupt and slowly varying changes in spectral matrices. Performance of the proposed model is evaluated by extensive simulations and demonstrated through the analysis of high-density electroencephalography.

Building on the concept of externalities, we propose an explanation of how multinationals can contribute to the enactment of the United Nations' Sustainable Development Goals as part of their ordinary investments. First, we suggest grouping the 17 Sustainable Development Goals into six categories based on whether they increase positive externalities - knowledge, wealth, or health - or reduce negative externalities - the overuse of natural resources, harm to social cohesion, or overconsumption. Second, we propose placing these categories within an extended value chain to facilitate their implementation. Third, we argue that multinationals' internal investments in host-country subsidiaries to improve their competitiveness contribute to addressing externalities in host-country communities, while external investments in host communities to solve underdevelopment generate competitiveness externalities on host-country subsidiaries., (© Academy of International Business 2021.)

Mono- and bis-decylated lumazines have been synthesized and characterized. Namely, mono-decyl chain [1-decylpteridine-2,4(1,3H)-dione] 6a and bis-decyl chain [1,3-didecylpteridine-2,4(1,3H)-dione] 7a conjugates were synthesized by nucleophilic substitution (S N 2) reactions of lumazine with 1-iododecane in N,N-dimethylformamide (DMF) solvent. Decyl chain coupling occurred at the N 1 site and then the N 3 site in a sequential manner, without DMF condensation. Molecular orbital (MO) calculations show a p-orbital at N 1 but not N 3 , which along with a nucleophilicity parameter (N) analysis predict alkylation at N 1 in lumazine. Only after the alkylation at N 1 in 6a, does a p-orbital on N 3 emerge thereby reacting with a second equivalent of 1-iododecane to reach the dialkylated product 7a. Data from NMR ( 1 H, 13 C, HSQC, HMBC), HPLC, TLC, UV-vis, fluorescence and density functional theory (DFT) provide evidence for the existence of mono-decyl chain 6a and bis-decyl chain 7a. These results differ to pterin O-alkylations (kinetic control), where N-alkylation of lumazine is preferred and then to dialkylation (thermodynamic control), with an avoidance of DMF solvent condensation. These findings add to the list of alkylation strategies for increasing sensitizer lipophilicity for use in photodynamic therapy., (© 2020 American Society for Photobiology.)