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1.
Environ Evid ; 12(1): 7, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-39294691

RESUMO

BACKGROUND: Among the most widely predicted climate change-related impacts to biodiversity are geographic range shifts, whereby species shift their spatial distribution to track their climate niches. A series of commonly articulated hypotheses have emerged in the scientific literature suggesting species are expected to shift their distributions to higher latitudes, greater elevations, and deeper depths in response to rising temperatures associated with climate change. Yet, many species are not demonstrating range shifts consistent with these expectations. Here, we evaluate the impact of anthropogenic climate change (specifically, changes in temperature and precipitation) on species' ranges, and assess whether expected range shifts are supported by the body of empirical evidence. METHODS: We conducted a Systematic Review, searching online databases and search engines in English. Studies were screened in a two-stage process (title/abstract review, followed by full-text review) to evaluate whether they met a list of eligibility criteria. Data coding, extraction, and study validity assessment was completed by a team of trained reviewers and each entry was validated by at least one secondary reviewer. We used logistic regression models to assess whether the direction of shift supported common range-shift expectations (i.e., shifts to higher latitudes and elevations, and deeper depths). We also estimated the magnitude of shifts for the subset of available range-shift data expressed in distance per time (i.e., km/decade). We accounted for methodological attributes at the study level as potential sources of variation. This allowed us to answer two questions: (1) are most species shifting in the direction we expect (i.e., each observation is assessed as support/fail to support our expectation); and (2) what is the average speed of range shifts? REVIEW FINDINGS: We found that less than half of all range-shift observations (46.60%) documented shifts towards higher latitudes, higher elevations, and greater marine depths, demonstrating significant variation in the empirical evidence for general range shift expectations. For the subset of studies looking at range shift rates, we found that species demonstrated significant average shifts towards higher latitudes (average = 11.8 km/dec) and higher elevations (average = 9 m/dec), although we failed to find significant evidence for shifts to greater marine depths. We found that methodological factors in individual range-shift studies had a significant impact on the reported direction and magnitude of shifts. Finally, we identified important variation across dimensions of range shifts (e.g., greater support for latitude and elevation shifts than depth), parameters (e.g., leading edge shifts faster than trailing edge for latitude), and taxonomic groups (e.g., faster latitudinal shifts for insects than plants). CONCLUSIONS: Despite growing evidence that species are shifting their ranges in response to climate change, substantial variation exists in the extent to which definitively empirical observations confirm these expectations. Even though on average, rates of shift show significant movement to higher elevations and latitudes for many taxa, most species are not shifting in expected directions. Variation across dimensions and parameters of range shifts, as well as differences across taxonomic groups and variation driven by methodological factors, should be considered when assessing overall confidence in range-shift hypotheses. In order for managers to effectively plan for species redistribution, we need to better account for and predict which species will shift and by how much. The dataset produced for this analysis can be used for future research to explore additional hypotheses to better understand species range shifts.

2.
Res Involv Engagem ; 6: 25, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32477591

RESUMO

BACKGROUND: Patient engagement strategies in health service delivery have become more common in recent years. However, many healthcare organizations are challenged in identifying the best methods to engage patients in health information technology (IT) initiatives. Engaging with important stakeholders to identify effective opportunities can inform the development of a resource that addresses this issue and supports organizations in their endeavors. The purpose of this paper is to share our experience and lessons learned from applying a novel consensus-building technique in order to identify key elements for effective patient engagement in health IT initiatives. This will be done through a case study approach. METHODS: Patients, family members of patients, health professionals, researchers, students, vendor representatives and individuals who work in health IT roles in health organizations were engaged through a one-day symposium in Toronto, Canada in September, 2018. During the symposium, the Group Priority Sort technique was used to obtain structured feedback from symposium attendees in the context of small group discussions. Descriptive statistics and a content analysis were undertaken to analyze the data collected through the Group Priority Sort as well as participant feedback following the symposium. RESULTS: A total of 37 participants attended the symposium from a variety of settings and organizations. Using the Group Priority Sort technique, 30 topics were classified by priority to be included in a future resource. Participant feedback pertaining to the symposium and research methods was largely positive. Several areas of improvement, such as clarity of items, were identified from this case study. CONCLUSIONS: The Group Priority Sort technique was an efficient method for obtaining valuable suggestions from a diverse group of stakeholders, including patients and family members. The specific priorities and feedback obtained from the symposium will be incorporated into a resource for healthcare organizations to aid them in engaging patients in health IT initiatives. Additionally, five important considerations were identified when conducting future work with the Group Priority Sort technique and are outlined in this paper.

3.
Int J Gen Med ; 10: 293-303, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28979157

RESUMO

Lack of physical activity is a global public health issue. Behavioral change interventions utilizing smartphone applications (apps) are considered a potential solution. The purpose of this literature review was to: 1) determine whether smartphone-based interventions encourage the initiation of, and participation in, physical activity; 2) explore the success of interventions in different populations; and 3) examine the key factors of the interventions that successfully encouraged physical activity. Eight databases (Medline, Scopus, EBM Reviews-Cochrane Central Register of Controlled Trials, EBM Reviews-Cochrane Database of Systematic Reviews, PsycInfo, SportDISCUS, CINAHL, and EMBASE) were searched and studies reporting physical activity outcomes following interventions using smartphone apps in adults were included in the narrative review. Results were mixed with eight studies reporting increased physical activity and ten reporting no change. Interventions did not appear to be successful in specific populations defined by age, sex, country, or clinical diagnosis. There was no conclusive evidence that a specific behavioral theory or behavioral change technique was superior in eliciting behavioral change. The literature remains limited primarily to short-term studies, many of which are underpowered feasibility or pilot studies; therefore, many knowledge gaps regarding the effectiveness of smartphone apps in encouraging physical activity remain. Robust studies that can accommodate the fast pace of the technology industry are needed to examine outcomes in large populations.

4.
Curr Probl Diagn Radiol ; 46(1): 6-9, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27268320

RESUMO

OBJECTIVE: To optimize resource utilization of cholescintigraphy for suspected acute cholecystitis with a time-saving method without a loss in diagnostic accuracy. MATERIALS AND METHODS: Institutional review board approval was obtained for this retrospective study. Hepatobiliary imaging data for 81 patients with suspected acute cholecystitis were recalled for modification into 2 summed static images, using only the first and last 5 minutes of the dynamic images, thereby eliminating the middle 50 minutes of imaging data. Two nuclear medicine physicians interpreted the summed images to assess visualization, and those interpretations were compared to the original reports based on using all 60 minutes of dynamic imaging. A third nuclear medicine physician mediated rare inter-reader interpretive disagreements. Comparison of interpretations of time-saving and conventional methods and also inter-observer variability was achieved using the Cohen κ coefficient analysis. RESULTS: Interpretations rendered using the time-saving method showed near-perfect agreement with those based on the full dynamic imaging protocol (Cohen κ coefficient = 0.92 for both readers). Furthermore, nuclear medicine physician readers agreed with each other (Cohen κ coefficient = 0.95 between the 2 readers), indicating minimal inter-observer variability using this novel optimized technique. CONCLUSION: In the setting of suspected acute cholecystitis, imaging resource utilization may be improved, via reduced gamma camera and technologist time, using a novel time-saving method without sacrificing diagnostic accuracy. Multicenter larger trials, however, will be necessary to establish reproducibility.


Assuntos
Colecistite Aguda/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Vesícula Biliar/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Projetos Piloto , Cintilografia , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Adulto Jovem
5.
Behav Ther ; 41(2): 254-65, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20412890

RESUMO

Current models divide social phobia into specific (SSP) and generalized (GSP) subtypes and suggest strong overlap between GSP and avoidant personality disorder (APD). Meanwhile, other research suggests reclassifying anxiety and mood disorders as fear and distress disorders. To unify these separate lines of research, this study was designed to test the hypothesis that SSP is more related to fear disorders (e.g., panic and phobias), whereas GSP and APD are more related to distress disorders (e.g., depression and generalized anxiety). Confirmatory factor analysis suggested the best-fitting model had symptoms of GSP, APD, and depression loading on one factor, and symptoms of SSP, panic, and specific phobias loading on a second factor. Key components of this model were (a) the inclusion of GAD symptoms reduced model fit and (b) GSP and APD symptoms significantly predicted SSP symptoms; this is consistent with conceptualizations of individuals with both GSP and SSP reporting performance anxiety.


Assuntos
Afeto , Ansiedade/diagnóstico , Modelos Psicológicos , Transtornos Fóbicos/diagnóstico , Adolescente , Adulto , Ansiedade/psicologia , Depressão/diagnóstico , Depressão/psicologia , Diagnóstico Diferencial , Análise Fatorial , Feminino , Humanos , Masculino , Pânico , Transtornos da Personalidade/diagnóstico , Transtornos da Personalidade/psicologia , Transtornos Fóbicos/psicologia , Escalas de Graduação Psiquiátrica , Adulto Jovem
6.
Behav Ther ; 41(1): 2-13, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20171323

RESUMO

This study's primary goal was to examine relations between symptoms of specific social phobia (SSP), generalized social phobia (GSP), avoidant personality disorder (APD), and panic and depression. Past research has suggested a single social phobia continuum in which SSP displays less symptom severity than GSP or APD. We found SSP symptoms correlated less strongly with depression but more strongly with panic relative to both GSP and APD symptoms. These findings challenge a unidimensional model of social phobia, suggesting a multidimensional model may be more appropriate. These findings also inform current research aimed at classifying mood and anxiety disorders more broadly by identifying that the different factors of fear versus distress appear to underlie different subtypes of social phobia.


Assuntos
Transtorno Depressivo/diagnóstico , Transtorno de Pânico/diagnóstico , Transtornos da Personalidade/diagnóstico , Transtornos Fóbicos/diagnóstico , Adolescente , Adulto , Transtorno Depressivo/classificação , Feminino , Humanos , Masculino , Transtorno de Pânico/classificação , Transtornos da Personalidade/classificação , Transtornos Fóbicos/classificação , Escalas de Graduação Psiquiátrica , Análise de Regressão , Inquéritos e Questionários , Adulto Jovem
7.
J Am Chem Soc ; 131(9): 3307-16, 2009 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-19219982

RESUMO

A new redox-active, tris(amido) ligand platform, bis(2-isopropylamino-4-methoxyphenylamine [NNN(cat)](3-), has been prepared and used in the preparation of tantalum(V) complexes. The ligand was prepared in its protonated form by a three-step procedure from commercially available 4-methoxy-2-nitroaniline and 1-iodo-4-methoxy-2-nitrobenzene. Direct reaction of [NNN(cat)]H(3) with TaCl(2)Me(3) afforded five-coordinate [NNN(cat)]TaCl(2) (1), which accepted the strong sigma-donor ligand (t)BuNC to form the six-coordinate adduct [NNN(cat)]TaCl(2)(CN(t)Bu) (2). Complex 1 is formally a d(0), Ta(V) complex; however, one- and two-electron reactivity is enabled at the metal center by the redox-activity of the ligand platform. Complex 1 was oxidized by one electron to afford the radical species [NNN(sq*)]TaCl(3) (3), which was characterized by solution EPR spectroscopy. Cyclic voltammetry studies of complex 3 showed clean one-electron oxidation and reduction processes at 0.148 and -0.324 V vs [Cp(2)Fe](+/0), indicating the accessibility of three oxidation states, [NNN(cat)](3-), [NNN(sq*)](2-), and [NNN(q)](-), for the metallated ligand. Complex 1 also can undergo two-electron reactions, as evidenced by the reaction with nitrene transfer reagents to form tantalum imido species. Thus 1 reacted with organic azides, RN(3) (R = Ph, p-C(6)H(4)Me, p-C(6)H(4)(t)Bu), to form [NNN(q)]TaCl(2)(NR) (4). Similarly, the tantalum diphenylmethylidenehydrazido complex, [NNN(q)]TaCl(2)(NNCPh(2)) (5), was formed by reaction of 1 with the diazoalkane, N(2)CPh(2).


Assuntos
Aminas/química , Elétrons , Compostos Organometálicos/síntese química , Tantálio/química , Ligantes , Estrutura Molecular , Compostos Organometálicos/química , Oxirredução
8.
J Phys Chem B ; 112(34): 10399-404, 2008 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-18681469

RESUMO

NMR spectra were collected for cross-linked poly(N-isopropylacrylamide), poly(NIPAM), hydrogels in the presence of NaCl and CaCl2 aqueous solutions. Intensity variations in the 1H NMR signals of the polymer provide insight into the phase transition process. These data were used to observe a two-stage phase transition process. Thermodynamic quantities were obtained from a van't Hoff analysis of the temperature-dependent equilibrium constants, which were derived from the NMR data. The Delta H degrees and Delta S degrees values for the hydrogel in D2O are 3.4 kJ/mol and 11.2 J/mol.K for stage I, which is attributed to the formation of hydrophobic bonds between neighboring isopropyl groups. The formation of hydrogen bonds during stage II yielded Delta H degrees and Delta S degrees values of 14.8 kJ/mol and 48.4 J/mol.K in D2O. However, the corresponding Delta H degrees values in 150 mM NaCl and 150 mM CaCl2 are reduced to 1.5 and 1.8 kJ/mol for stage I of the dehydration process. This corresponds to the known effect of salts on hydrophobic bond energetics. The value of Delta S degrees also decreased to 4.9 and 5.9 J/mol.K in NaCl and CaCl2 solutions, respectively. However, the thermodynamic values during stage II were only slightly affected by the salts. The lower temperatures required to induce spontaneous precipitation implies that Delta G degrees of precipitation is reduced. With our measurement of equilibrium thermodynamics, we see that 150 mM NaCl and CaCl2 solutions have a greater effect on hydrophobic bond formation associated with the phase transition process. In this manner, these salts aid in solvent reorganization necessary to form the hydrophobic bond, and this suggests that the formation of hydrophobic bonds is a strong determining factor in the stability of poly(NIPAM) hydrogels in water.


Assuntos
Acrilamidas/química , Espectroscopia de Ressonância Magnética/métodos , Transição de Fase , Polímeros/química , Termodinâmica , Acrilamidas/síntese química , Resinas Acrílicas , Cloreto de Cálcio/química , Dessecação , Óxido de Deutério/química , Entropia , Temperatura Alta , Hidrogéis/química , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Polímeros/síntese química , Cloreto de Sódio/química , Temperatura
9.
J Am Chem Soc ; 130(18): 5838-9, 2008 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-18402446

RESUMO

The neutral imino-semiquinone, 4,6-di-tert-butyl-2-tert-butylimino-semiquinone (isqH.), can be prepared by a conproportionation of the parent aminophenol and iminoquinone compounds. The neutral radical species has been characterized in the solid state by X-ray diffraction and in solution by EPR and UV-vis absorption spectroscopy. The stability of the open-shell radical is derived from the basicity of the tert-butylimino group and the intramolecular hydrogen bond.


Assuntos
Benzoquinonas/química , Iminas/química , Benzoquinonas/isolamento & purificação , Eletroquímica , Espectroscopia de Ressonância de Spin Eletrônica , Concentração de Íons de Hidrogênio , Iminas/isolamento & purificação , Termodinâmica , Difração de Raios X
10.
J Anxiety Disord ; 22(5): 824-36, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17904796

RESUMO

Cognitive models of Obsessive-Compulsive Disorder (OCD) posit that certain beliefs are important to the development and maintenance of OCD symptoms. The Obsessive Beliefs Questionnaire (OBQ) is a new measure developed to assess these beliefs. Supported by initial research, this study further examined the OBQ, focusing on structural issues and its relations with OCD and other symptoms. Results were that previous 3- and 4-factor models did not fit the current data adequately using confirmatory factor analysis (CFA). However, a modified 3-factor model was generated using exploratory factor analysis and subsequently supported using CFA. The OBQ showed specific relevance to OCD and not to Panic Disorder or Major Depression once general distress was controlled. Only modest specificity was found within relations between OBQ scales and particular OCD scales, such as those involving beliefs about Perfectionism/Certainty and OCD rituals pertaining to symmetry, ordering, arranging, and grooming.


Assuntos
Transtornos Cognitivos/diagnóstico , Transtorno Obsessivo-Compulsivo/diagnóstico , Inventário de Personalidade/estatística & dados numéricos , Inquéritos e Questionários , Adulto , Transtornos Cognitivos/psicologia , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/psicologia , Análise Fatorial , Feminino , Humanos , Masculino , Modelos Psicológicos , Transtorno Obsessivo-Compulsivo/psicologia , Transtorno de Pânico/diagnóstico , Transtorno de Pânico/psicologia , Psicometria , Sensibilidade e Especificidade
11.
Depress Anxiety ; 25(8): 641-52, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17948275

RESUMO

Research in obsessive-compulsive disorder (OCD) shows heterogeneous symptoms. No longer satisfied with categorizations of obsessions or compulsions, contemporary symptom measures are multidimensional and assess specific symptoms (e.g., checking, washing) as well as experiences bearing a putative relation to OCD (e.g., hoarding). This two-study correlational design examined three OCD measures in student samples (total N=805). Objectives were to evaluate (a) the measures' joint factor structure; (b) specificity of relations between OCD and symptoms of general distress, panic, and depression; and (c) the pattern of convergent and discriminant relations among OCD scales after accounting for general distress. Results were that both exploratory and confirmatory factor analyses supported a five-factor structure: checking, contamination, rituals, impulses, and hoarding. Scales showed meaningful patterns of relations with general distress, panic, and depression. That is, OCD symptoms correlated moderately with general distress and panic, but related more weakly to depression. Parallel scales measuring the five domains were reliable and showed strong convergence across instruments. After accounting for general distress, discriminant validity was found: Mono-trait correlations between instruments were the highest correlations overall and were substantially higher than hetero-trait values either within or between instruments. We discuss the importance of understanding relations among OCD measures, between OCD and other symptoms, and implications of this type of analysis for defining OCD.


Assuntos
Transtorno Obsessivo-Compulsivo/diagnóstico , Transtorno Obsessivo-Compulsivo/psicologia , Transtorno Depressivo/epidemiologia , Transtorno Depressivo/psicologia , Análise Fatorial , Feminino , Humanos , Masculino , Transtorno Obsessivo-Compulsivo/epidemiologia , Transtorno de Pânico/epidemiologia , Transtorno de Pânico/psicologia , Sensibilidade e Especificidade , Inquéritos e Questionários , Adulto Jovem
12.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 10): m1337, 2008 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-21201070

RESUMO

In the title compound, [Mo(C(44)H(28)N(4))(NO(3))O]·C(6)H(6), the porphyrin ring is centrosymmetric. The Mo atom, oxide ion and nitrate ion are equally disordered over two sites, such that the Mo atom is displaced by 0.366 (1) Štowards the oxide ion from the 24-atom mean plane of the porphyrin, and also makes a long Mo-O bond to a nitrate O atom. A centrosymmetric benzene solvent mol-ecule is situated between adjacent porphyrin mol-ecules.

13.
Environ Manage ; 40(2): 171-82, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17562105

RESUMO

Many problems and challenges of ecosystem management currently are driven by the rapid pace and spatial extent of landscape change. Parks and reserves within areas of high human population density are especially challenged to meet the recreational needs of local populations and to preserve valued environmental resources. The complex problem of managing multiple objectives and multiple resources requires an enormous quantity of information, and conceptual models have been proposed as tools for organizing and interpreting this information. Academics generally prefer a bottom-up approach to model construction that emphasizes ecologic theory and process, whereas managers often use a top-down approach that takes advantage of existing information to address more pragmatic objectives. The authors propose a formal process for developing, applying, and testing conceptual models to be used in landscape monitoring that reconciles these seemingly opposing perspectives. The four-step process embraces the role of hypothesis testing in the development of models and evaluation of their utility. An example application of the process to a network of national parks in and around Washington, DC illustrates the ability of the approach to systematically identify monitoring data that would both advance ecologic theory and inform management decisions.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Monitoramento Ambiental/normas , Animais , District of Columbia , Ecologia , Monitoramento Ambiental/métodos , Geografia , Humanos , Sistemas de Informação , Modelos Teóricos
14.
Dalton Trans ; (10): 1338-46, 2006 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-16505913

RESUMO

We have examined the redox behavior of the osmium and ruthenium compounds (OEP)M(NO)(OEt) and (OEP)M(NO)(SEt) (OEP = octaethylporphyrinato dianion; M = Os, Ru) by cyclic voltammetry and infrared spectroelectrochemistry. The compound (OEP)Os(NO)(OEt) undergoes a single reversible oxidation process in dichloromethane. In contrast, the thiolate compound (OEP)Os(NO)(SEt) undergoes a net irreversible oxidation resulting in formal loss of the SEt ligand. Extended Hückel calculations on crystal structures of these two compounds provide insight into the nature of their HOMOs. In the case of the alkoxide compound, the HOMO is largely metal centered, with 70% of the charge located in the metal's orbital and approximately 25% on the porphyrin ring. However, the HOMO of the thiolate compound consists of a pi bonding interaction between the metal dxz orbital and the px orbital on the sulfur, and a pi antibonding interaction between the metal d orbital and a pi* orbital on NO. The redox behavior of the Ru analogues have been determined, and are compared with those of the Os compounds.

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