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The development of many quantum optical technologies depends on the availability of single quantum emitters with near-perfect coherence. Systematic improvement is limited by a lack of understanding of the microscopic energy flow at the single-emitter level and ultrafast timescales. Here we utilize a combination of fluorescence correlation spectroscopy and ultrafast spectroscopy to capture the sample-averaged dynamics of defects with single-particle sensitivity. We employ this approach to study heterogeneous emitters in two-dimensional hexagonal boron nitride. From milliseconds to nanoseconds, the translational, shelving, rotational and antibunching features are disentangled in time, which quantifies the normalized two-photon emission quantum yield. Leveraging the femtosecond resolution of this technique, we visualize electron-phonon coupling and discover the acceleration of polaronic formation on multi-electron excitation. Corroborated with theory, this translates to the photon fidelity characterization of cascaded emission efficiency and decoherence time. Our work provides a framework for ultrafast spectroscopy in heterogeneous emitters, opening new avenues of extreme-scale characterization for quantum applications.
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Confinement of monolayers into quasi-1D atomically thin nanoribbons could lead to novel quantum phenomena beyond those achieved in their bulk and monolayer counterparts. However, current experimental availability of nanoribbon species beyond graphene is limited to bottom-up synthesis or lithographic patterning. In this study, a versatile and direct approach is introduced to exfoliate bulk van der Waals crystals as nanoribbons. Akin to the Scotch tape exfoliation method for producing monolayers, this technique provides convenient access to a wide range of nanoribbons derived from their corresponding bulk crystals, including MoS2, WS2, MoSe2, WSe2, MoTe2, WTe2, ReS2, and hBN. The nanoribbons are predominantly monolayer, single-crystalline, parallel-aligned, flat, and exhibit high aspect ratios. The role of confinement, strain, and edge configuration of these nanoribbons is observed in their electrical, magnetic, and optical properties. This versatile exfoliation technique provides a universal route for producing a variety of nanoribbon materials and supports the study of their fundamental properties and potential applications.
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The freshwater phase of the first seaward migration of juvenile Atlantic salmon (Salmo salar) is relatively well understood when compared with our understanding of the marine phase of their migration. In 2021, 1008 wild and 60 ranched Atlantic salmon smolts were tagged with acoustic transmitters in 12 rivers in England, Scotland, Northern Ireland and Ireland. Large marine receiver arrays were deployed in the Irish Sea at two locations: at the transition of the Irish Sea into the North Atlantic between Ireland and Scotland, and between southern Scotland and Northern Ireland, to examine the early phase of the marine migration of Atlantic salmon smolts. After leaving their natal rivers' post-smolt migration through the Irish Sea was rapid with minimum speeds ranging from 14.03 to 38.56 km.day-1 for Atlantic salmon smolts that entered the Irish Sea directly from their natal river, to 9.69-39.94 km.day-1 for Atlantic salmon smolts that entered the Irish Sea directly from their natal estuary. Population minimum migration success through the study area was strongly correlated with the distance of travel, populations further away from the point of entry to the open North Atlantic exhibited lower migration success. Post-smolts from different populations experienced different water temperatures on entering the North Atlantic. This was largely driven by the timing of their migration and may have significant consequences for feeding and ultimately survivorship. The influence of water currents on post-smolt movement was investigated using data from previously constructed numerical hydrodynamic models. Modeled water current data in the northern Irish Sea showed that post-smolts had a strong preference for migrating when the current direction was at around 283° (west-north-west) but did not migrate when exposed to strong currents in other directions. This is the most favorable direction for onward passage from the Irish Sea to the continental shelf edge current, a known accumulation point for migrating post-smolts. These results strongly indicate that post-smolts migrating through the coastal marine environment are: (1) not simply migrating by current following (2) engage in active directional swimming (3) have an intrinsic sense of their migration direction and (4) can use cues other than water current direction to orientate during this part of their migration.
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Rios , Salmo salar , Animais , Sinais (Psicologia) , Migração Animal , ÁguaRESUMO
There is some evidence that the river migration success of Atlantic salmon smolts, on their first migration to sea, varies both spatially and temporally. However, we have only a poor understanding of what may be driving this variation. In this study, we used acoustic telemetry to quantify the spatial and temporal variations in river migration success in Atlantic salmon smolts on their first migration to sea. In total 4120 Atlantic salmon smolts migrating through 22 rivers in Scotland, England, Ireland, and Northern Ireland over multiple years were included in the study. Individuals were defined as successful migrants if detected leaving the river to enter marine waters. The results show significant temporal (up to 4 years) and spatial (river) variations in migration success, with overall between-river migration success varying from 3.4% to 97.0% and between years from 3.4% and 61.0%. Temporal variation in migration success was river specific, with some rivers being more temporally stable (exhibiting little variation between years) than others. Across all rivers and years, individual migration success was predicted positively by body condition and negatively by tag burden. The rate of migration success for a population (migration success standardized to a common river distance [proportion km-1]) was predicted by a number of environmental factors. The proportion of river catchment that comprised wetland and woodland positively predicted migration success, whereas the proportion of grassland and peatland in a catchment negatively predicted the rate of migration success. Although the mechanisms through which these effects may be operating were not directly examined in this study, we discuss some potential routes through which they may occur.
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The migratory behavior of Atlantic salmon (Salmo salar) post-smolts in coastal waters is poorly understood. In this collaborative study, 1914 smolts, from 25 rivers, in four countries were tagged with acoustic transmitters during a single seasonal migration. In total, 1105 post-smolts entered the marine study areas and 438 (39.6%) were detected on a network of 414 marine acoustic receivers and an autonomous underwater vehicle. Migration pathways (defined as the shortest distance between two detections) of up to 575 km and over 100 days at sea were described for all 25 populations. Post-smolts from different rivers, as well as individuals from the same river, used different pathways in coastal waters. Although difficult to generalize to all rivers, at least during the year of this study, no tagged post-smolts from rivers draining into the Irish Sea were detected entering the areas of sea between the Hebrides and mainland Scotland, which is associated with a high density of finfish aquaculture. An important outcome of this study is that a high proportion of post-smolts crossed through multiple legislative jurisdictions and boundaries during their migration. This study provides the basis for spatially explicit assessment of the impact risk of coastal pressures on salmon during their first migration to sea.
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Exposure to minority stress is the primary mechanism through which lesbian, gay, bisexual, transgender, queer, and questioning (LGBTQ) youth experience a greater risk for suicide. The current study examines the association of LGBTQ-based cumulative minority stress with suicide risk using online survey data collected from 39,126 LGBTQ youth ages 13-24 in the United States. Youth who reported four types of minority stress had nearly 12 times greater odds of attempting suicide compared to those who reported none. Transgender and nonbinary youth and American Indian/Alaskan Native youth had higher odds of reporting three or more minority stress experiences. The strong association of cumulative risk with attempted suicide and disproportionate exposure among marginalized members of the LGBTQ community highlight the need for suicide prevention to prioritize those at greatest risk and for research examining LGBTQ suicide risk to employ cumulative risk models.
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Minorias Sexuais e de Gênero , Pessoas Transgênero , Adolescente , Adulto , Bissexualidade , Feminino , Identidade de Gênero , Humanos , Tentativa de Suicídio , Estados Unidos/epidemiologia , Adulto JovemRESUMO
Community-based organizations (CBOs) must have the capacity to adopt, implement, and sustain evidence-based practices (EBPs). However, limited research exists examining CBOs' ability/capacity to implement EBPs. The purpose of this preliminary study was to investigate how staff of CBOs perceive implementation practice capacity, determine factors needed for adequate capacity for implementing EBPs, and examine which perspectives of capacity are shared across organizational levels. Ninety-seven administrators and practitioners of CBOs were surveyed using the Implementation Capacity Survey, which examines perceived importance, presence, and organizational capacity of the CBO in nine implementation practice areas (IPAs) (e.g., leadership). Results revealed participants rated IPAs on the importance scale higher than IPAs on the present scale. Presence and organizational capacity scales were strongly correlated, and results showed significant differences between administrators and practitioners on ratings of presence and organizational capacity. Implications for future research aimed at examining/building implementation practice capacity in community settings will be discussed.
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Prática Clínica Baseada em Evidências , Organizações , Humanos , Liderança , Saúde PúblicaRESUMO
Social and Emotional Learning (SEL) programs seek to enhance social and emotional competencies in children, including self-awareness, self-management, social awareness, relationship skills, and responsible decision-making. By means of direct instruction regarding social and emotional competencies, SEL programs have the potential to strengthen resilience in children and thus their capacity to effectively cope with life's challenges. Strengthening resilience in children who are repeatedly exposed to adverse experiences, particularly those from economically disadvantaged minority backgrounds, is of particular importance and has implications for the prevention of a multitude of problems later in life. Our study reports the result of an investigation of the SPARK Child Mentoring program, a resilience-focused SEL program designed to reduce risk factors, uncover innate resilience, promote natural emotional well-being, and facilitate school success. We employed a randomized controlled trial comprising 94 elementary school students that included pre- and post-intervention measurements. After controlling for pre-intervention levels, we found a significant difference between students' understanding of underlying program principles; communication, decision making, and problem-solving skills; emotional regulation; and resilience for students who received the intervention compared to students who did not receive the intervention. These results provide initial evidence for the efficacy of the SPARK Child Mentoring program with a diverse sample of elementary school students and adds to the existing literature base concerning positive outcomes associated with SEL programs. We discuss implications for future research focused on long-term preventive effects of the program and the characteristics of students most likely to benefit from it.
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Tutoria , Criança , Currículo , Emoções , Humanos , Avaliação de Programas e Projetos de Saúde , Instituições Acadêmicas , EstudantesRESUMO
Objectives. To explore associations between undergoing sexual orientation or gender identity conversion efforts (SOGICE) and suicidality among young LGBTQ (lesbian, gay, bisexual, transgender, and queer or questioning) individuals.Methods. Data were derived from a 2018 online cross-sectional study of young LGBTQ individuals (13-24 years of age) residing in the United States. Multivariate logistic regression was used to determine the relative odds of suicidality among young LGBTQ individuals who experienced SOGICE (in comparison with those who did not) after adjustment for age, race/ethnicity, geography, parents' use of religion to say negative things about being LGBTQ, sexual orientation, gender identity, discrimination because of sexual orientation or gender identity, and physical threats or harm because of sexual orientation or gender identity.Results. Relative to young people who had not experienced SOGICE, those who reported undergoing SOGICE were more than twice as likely to report having attempted suicide and having multiple suicide attempts.Conclusions. The elevated odds of suicidality observed among young LGBTQ individuals exposed to SOGICE underscore the detrimental effects of this unethical practice in a population that already experiences significantly greater risks for suicidality.
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Aconselhamento/estatística & dados numéricos , Identidade de Gênero , Autorrelato , Minorias Sexuais e de Gênero/estatística & dados numéricos , Tentativa de Suicídio/estatística & dados numéricos , Adolescente , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Comportamento Sexual , Minorias Sexuais e de Gênero/psicologia , Inquéritos e Questionários , Estados Unidos , Adulto JovemRESUMO
Ozonolysis of alkenes, an important nonphotolytic source of hydroxyl (OH) radicals in the atmosphere, proceeds through unimolecular decay of Criegee intermediates. Here, we report a large kinetic isotope effect associated with the rate-limiting hydrogen-transfer step that releases OH radicals for a prototypical Criegee intermediate, CH3CHOO. IR excitation of selectively deuterated syn-CD3CHOO is shown to result in deuterium atom transfer and release OD radical products. Vibrational activation of syn-CD3CHOO is coupled with direct time-resolved detection of OD products to measure a 10-fold slower rate of unimolecular decay upon deuteration in the vicinity of the transition state barrier, which is confirmed by microcanonical statistical theory that incorporates quantum mechanical tunneling. The corresponding kinetic isotope effect of â¼10 is attributed primarily to the decreased probability of D-atom vs. H-atom transfer arising from tunneling. Master equation modeling is utilized to compute the thermal unimolecular decay rates for selectively and fully deuterated syn methyl-substituted Criegee intermediates under atmospheric conditions. At 298 K (1 atm), tunneling is predicted to enhance the thermal decay rate of syn-CH3CHOO compared with the deuterated species, giving rise to a significant kinetic isotope effect of â¼50.
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Recruiting schools for intervention research can be daunting. This study examined the experiences of researchers recruiting public high schools for a randomized controlled trial to reduce suicide disparities for sexual and gender minority (SGM) youth by implementing evidence-based strategies to enhance school environments. We enrolled 42 schools throughout New Mexico between August 2016 and April 2017. Based on qualitative analysis of recruitment efforts, three groups of factors affected enrollment: (1) non-SGM-specific factors, (2) SGM-specific factors, and (3) facilitating factors. Non-SGM-specific factors negatively impacted the willingness or ability to participate (e.g., demanding staff workloads and beliefs that "outsiders" should not assist with school-based interventions). Notable SGM-specific factors centered on influences in socially conservative community environments and beliefs that schools lacked SGM students. Advocacy, leveraging relationships, and persistence were facilitating factors for overcoming recruitment obstacles. Our findings have implications for researchers and school nurses interested in school-based interventions, especially those focused on SGM youth.
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Seleção de Pacientes , Ensaios Clínicos Controlados Aleatórios como Assunto , Instituições Acadêmicas , Minorias Sexuais e de Gênero , Estudantes , Prevenção do Suicídio , Adolescente , Adulto , Humanos , New Mexico , Pesquisa QualitativaRESUMO
High levels of emotional exhaustion are frequently reported among clinicians working in community mental health settings. This study draws on social exchange theory and examines the relationships between emotional exhaustion and mental health provider work attitudes and turnover, and the moderating effect of functional psychological climates. Data were analyzed using multilevel structural equation modeling in a sample of 311 mental health providers from 49 community mental health programs. Results revealed that emotional exhaustion was negatively related to work attitudes, and the relationship was moderated by functional climates characterized by high levels of cooperation, growth and advancement opportunities, and role clarity. Specifically, the relationship between emotional exhaustion and work attitudes was attenuated for providers working in programs with a more functional psychological climate. Lower work attitudes significantly predicted higher clinician turnover. Results are discussed as they relate to improving climates and enhancing mental health provider and organizational well-being.
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Atitude , Esgotamento Profissional , Emoções , Fadiga/psicologia , Reorganização de Recursos Humanos/tendências , Adulto , California , Serviços Comunitários de Saúde Mental , Feminino , Previsões , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e QuestionáriosRESUMO
The reaction of ozone with isoprene, one of the most abundant volatile organic compounds in the atmosphere, produces three distinct carbonyl oxide species (RR'COO) known as Criegee intermediates: formaldehyde oxide (CH2OO), methyl vinyl ketone oxide (MVK-OO), and methacrolein oxide (MACR-OO). The nature of the substituents (R,R' = H, CH3, CHâCH2) and conformations of the Criegee intermediates control their subsequent chemistry in the atmosphere. In particular, unimolecular decay of MVK-OO is predicted to be the major source of hydroxyl radicals (OH) in isoprene ozonolysis. This study reports the initial laboratory synthesis and direct detection of MVK-OO through reaction of a photolytically generated, resonance-stabilized monoiodoalkene radical with O2. MVK-OO is characterized utilizing infrared (IR) action spectroscopy, in which IR activation of MVK-OO with two quanta of CH stretch at ca. 6000 cm-1 is coupled with ultraviolet detection of the resultant OH products. MVK-OO is identified by comparison of the experimentally observed IR spectral features with theoretically predicted IR absorption spectra. For syn-MVK-OO, the rate of appearance of OH products agrees with the unimolecular decay rate predicted using statistical theory with tunneling. This validates the hydrogen atom transfer mechanism and computed transition-state barrier (18.0 kcal mol-1) leading to OH products. Theoretical calculations reveal an additional roaming pathway between the separating radical fragments, which results in other products. Master equation modeling yields a thermal unimolecular decay rate for syn-MVK-OO of 33 s-1 (298 K, 1 atm). For anti-MVK-OO, theoretical exploration of several unimolecular decay pathways predicts that isomerization to dioxole is the most likely initial step to products.
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OBJECTIVE: We examine how frontline workers and supervisors delivering a research supported intervention (RSI) to reduce child neglect negotiated system-related challenges, the pragmatics of RSI implementation, and their professional identities and relationships with clients. METHODS: We conducted semi-structured interviews, small group discussions, and focus groups with frontline workers and supervisors in one large county over two time periods. We used iterative coding to analyze qualitative data. RESULTS: Frontline workers navigated several aspects of RSI implementation and sustainment: (1) contract requirements and information dissemination, (2) fidelity, (3) competing demands and crises, (4) structure versus creativity, and (5) relationships with clients. CONCLUSIONS: Workers dynamically negotiated multiple system- and provider-level (or outer- and inner-contextual) demands influencing RSI provision for clients with complex service needs. Results affirm the need to attend to the unintended consequences of implementing new contract, reimbursement, and other system organizational processes and to address the "committed work" supporting RSI delivery.
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The hydroxyl radical (OH) is a key oxidant in atmospheric and combustion chemistry. Recently, a sensitive and state-selective ionization method has been developed for detection of the OH radical that utilizes UV excitation on the A(2)Σ(+)-X(2)Π transition followed by fixed 118 nm vacuum ultraviolet (VUV) radiation to access autoionizing Rydberg states [J. M. Beames et al., J. Chem. Phys. 134, 241102 (2011)]. The present study uses tunable VUV radiation generated by four-wave mixing to examine the origin of the enhanced ionization efficiency observed for OH radicals prepared in specific A(2)Σ(+) intermediate levels. The enhancement is shown to arise from resonant excitation to distinct rotational and fine structure levels of two newly identified (2)Π Rydberg states with an A(3)Π cationic core and a 3d electron followed by ionization. Spectroscopic constants are derived and effects due to uncoupling of the Rydberg electron are revealed for the OH (2)Π Rydberg states. The linewidths indicate a Rydberg state lifetime due to autoionization on the order of a picosecond.
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Sustainment of evidence-based interventions (EBIs) in human services depends on the inner context of community-based organizations (CBOs) that provide services and the outer context of their broader environment. Increasingly, public officials are experimenting with contracting models from for-profit industries to procure human services. In this case study, we conducted qualitative interviews with key government and CBO stakeholders to examine implementation of the Best Value-Performance Information Procurement System to contract for EBIs in a child welfare system. Findings suggest that stakeholder relationships may be compromised when procurement disregards local knowledge, communication, collaboration, and other factors supporting EBIs and public health initiatives.
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Serviços de Proteção Infantil/organização & administração , Serviços Contratados/organização & administração , Prática Clínica Baseada em Evidências/organização & administração , Visita Domiciliar , Criança , Proteção da Criança , Humanos , Estudos de Casos Organizacionais , Saúde Pública , Pesquisa Qualitativa , Aquisição Baseada em ValorRESUMO
If evidence-based interventions (EBIs) are not sustained, investments are wasted and public health impact is limited. Leadership has been suggested as a key determinant of implementation and sustainment; however, little empirical work has examined this factor. This mixed-methods study framed using the Exploration, Preparation, Implementation, Sustainment (EPIS) conceptual framework examines leadership in both the outer service system context and inner organizational context in eleven system-wide implementations of the same EBI across two U.S. states and 87 counties. Quantitative data at the outer context (i.e., system) and inner context (i.e., team) levels demonstrated that leadership predicted future sustainment and differentiated between sites with full, partial, or no sustainment. In the outer context positive sustainment leadership was characterized as establishing a project's mission and vision, early and continued planning for sustainment, realistic project plans, and having alternative strategies for project survival. Inner context frontline transformational leadership predicted sustainment while passive-avoidant leadership predicted non-sustainment. Qualitative results found that sustainment was associated with outer context leadership characterized by engagement in ongoing supportive EBI championing, marketing to stakeholders; persevering in these activities; taking action to institutionalize the EBI with funding, contracting, and system improvement plans; and fostering ongoing collaboration between stakeholders at state and county, and community stakeholder levels. For frontline leadership the most important activities included championing the EBI and providing practical support for service providers. There was both convergence and expansion that identified unique contributions of the quantitative and qualitative methods. Greater attention to leadership in both the outer system and inner organizational contexts is warranted to enhance EBI implementation and sustainment.
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Atitude do Pessoal de Saúde , Cuidadores/educação , Maus-Tratos Infantis/prevenção & controle , Proteção da Criança , Prática Clínica Baseada em Evidências , Liderança , Serviços de Saúde Mental , Saúde Pública , California , Serviços de Saúde da Criança , Pré-Escolar , Grupos Focais , Pessoal de Saúde , Humanos , Lactente , Recém-Nascido , Avaliação de Programas e Projetos de Saúde , Pesquisa QualitativaRESUMO
AIMS: The aims of this review were to summarize the scientific evidence about the risks of using methylphenidate for ADHD in pregnancy and lactation, to present a case in which interruption of treatment after delivery and during breastfeeding was harmful and to discuss the implications of treating or not treating ADHD in pregnancy and lactation. METHODS: For the systematic review, databases searched included Pubmed, Psychinfo, Web of Science, Embase, Biosis and Medline. RESULTS: Three articles were found with a total sample of 41 children exposed to methylphenidate in pregnancy. Malformations reported included congenital heart defects (n = 2), finger abnormalities (syndactyly, adactyly and polydactyly n = 2) and limb malformations (n = 1). Other problems included premature birth, asphyxia and growth retardation. One case report (n = 1) and one case series (n = 3) were identified regarding exposure to methylphenidate through breast feeding. In all cases, children developed normally and no adverse effects were reported. In our case report we describe an infant exposed to methylphenidate during pregnancy and breast feeding, who developed normally having no detectable congenital abnormalities. CONCLUSIONS: The number and size of the studies found were small. Identified cases were not representative of the general adult ADHD population having methylphenidate as monotherapy during pregnancy as all the articles reported combinations of methylphenidate with either known teratogenic drugs or drugs of abuse. There is a paucity of data regarding the use of methylphenidate in pregnancy and further studies are required. Although the default medical position is to interrupt any non-essential pharmacological treatment during pregnancy and lactation, in ADHD this may present a significant risk. Doctors need to evaluate each case carefully before interrupting treatment.
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Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Metilfenidato/efeitos adversos , Metilfenidato/uso terapêutico , Adolescente , Aleitamento Materno , Desenvolvimento Infantil/efeitos dos fármacos , Feminino , Humanos , Lactente , Lactação , Metilfenidato/administração & dosagem , Metilfenidato/farmacocinética , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Adulto JovemRESUMO
Dimethyl- and ethyl-substituted Criegee intermediates, (CH3)2COO and CH3CH2CHOO, are photolytically generated from diiodo precursors, detected by VUV photoionization at 118 nm, and spectroscopically characterized via UV-induced depletion of the m/z = 74 signals under jet-cooled conditions. In each case, UV excitation resonant with the B-X transition results in significant ground-state depletion, reflecting the large absorption cross section and rapid dynamics in the excited B state. The broad UV absorption spectra of both (CH3)2COO and CH3CH2CHOO peak at ~320 nm with absorption cross sections approaching ~4 × 10(-17) cm(2) molec(-1). The UV absorption spectra for (CH3)2COO and CH3CH2CHOO are similar to that reported previously for syn-CH3CHOO, suggesting analogous intramolecular interactions between the α-H and terminal O of the COO groups. Hydroxyl radical products generated concurrently with the Criegee intermediates are detected by 1 + 1' resonance enhanced multiphoton ionization. The OH signals, scaled relative to those for the Criegee intermediates, are compared with prior studies of OH yield from alkene ozonolysis. The stationary points along the reaction coordinates from the alkyl-substituted Criegee intermediates to vinyl hydroperoxides and OH products are also computed to provide insight on the OH yields.
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The goal of this study was to examine the relationships of transformational leadership and organizational climate with working alliance, in a children's mental health service system. Using multilevel structural equation modeling, the effect of leadership on working alliance was mediated by organizational climate. These results suggest that supervisors may be able to impact quality of care through improving workplace climate. Organizational factors should be considered in efforts to improve public sector services. Understanding these issues is important for program leaders, mental health service providers, and consumers because they can affect both the way services are delivered and ultimately, clinical outcomes.