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1.
Int J Biometeorol ; 68(4): 743-748, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38214750

RESUMO

Hot droughts, droughts attributed to below-average precipitation and exceptional warmth, are increasingly common in the twenty-first century, yet little is known about their effect on coniferous tree growth because of their historical rarity. In much of the American West, including California, radial tree growth is principally driven by precipitation, and narrow ring widths are typically associated with either drier or drought conditions. However, for species growing at high elevations (e.g., Larix lyalli, Pinus albicaulis), growth can be closely aligned with above-average temperatures with maximum growth coinciding with meteorological drought, suggesting that the growth effects of drought span from adverse to beneficial depending on location. Here, we compare radial growth responses of three high-elevation old-growth pines (Pinus jeffreyi, P. lambertiana, and P. contorta) growing in the San Jacinto Mountains, California, during a twenty-first-century hot drought (2000-2020) largely caused by exceptional warmth and a twentieth-century drought (1959-1966) principally driven by precipitation deficits. Mean radial growth during the hot drought was 12% above average while 18% below average during the mid-century drought illustrating that the consequences of environmental stress exhibit spatiotemporal variability. We conclude that the effects of hot droughts on tree growth in high-elevation forests may produce responses different than what is commonly associated with extended dry periods for much of western North America's forested lands at lower elevational ranges and likely applies to other mountainous regions (e.g., Mediterranean Europe) defined by summer-dry conditions. Thus, the climatological/biological interactions discovered in Southern California may offer clues to the unique nature of high-elevation forested ecosystems globally.


Assuntos
Ecossistema , Pinus , Secas , Pinus/fisiologia , Florestas , California
2.
J Gen Intern Med ; 31(1): 37-44, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26084975

RESUMO

BACKGROUND: Little is known about the factors that influence physicians' admission decisions, especially among lower acuity patients. For the purpose of our study, non-medical refers to all of the factors-other than the patient's clinical condition-that could potentially influence admission decisions. OBJECTIVE: To describe the influence of non-medical factors on physicians' decisions to admit non-critically ill patients presenting to the ED. DESIGN: Cross-sectional study of hospital admissions at a single academic medical center. PARTICIPANTS: Non-critically ill adult patients admitted to the hospital (n = 297) and the admitting emergency medicine physicians (n = 34). MAIN MEASURES: A patient survey assessed non-medical factors, including primary care access and utilization. A physician survey assessed clinical and non-medical factors influencing the decision to admit. Based on physician responses, admissions were characterized as "strongly acuity-driven," "moderately acuity-driven," or "weakly acuity-driven." Among these admission types, we compared length of stay, cost, and readmission within 30 days to the hospital or ED. KEY RESULTS: Based on the admitting physician's assessment, we categorized the motivation for admission as strongly acuity-driven in 185 (62 %) admissions, moderately acuity-driven in 92 (31 %), and weakly acuity-driven in 20 (7 %). Per the physician surveys, 51 % of hospitalizations were strongly or moderately influenced by one or more non-medical factors, including lack of information about baseline conditions (23 %); inadequate access to outpatient specialty care (14 %); need for a diagnostic testing or procedure (12 %); a recent ED visit (11 %); and inadequate access to primary care (10 %). Compared with strongly-acuity driven admissions, admissions that were moderately or weakly acuity-driven were shorter and less costly but were associated with similar rates of ED (35 %) and hospital (27 %) readmission. CONCLUSIONS: Non-medical factors are influential in the admission decisions for many patients presenting to the emergency department. Moderately and weakly acuity-driven admissions may represent a feasible target for alternative care pathways.


Assuntos
Doença Aguda/terapia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Admissão do Paciente/tendências , Inquéritos e Questionários , Centros Médicos Acadêmicos/estatística & dados numéricos , Doença Aguda/epidemiologia , Estado Terminal , Estudos Transversais , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Estados Unidos/epidemiologia
3.
Archaea ; 2013: 373275, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24151449

RESUMO

Extremophiles, especially those in Archaea, have a myriad of adaptations that keep their cellular proteins stable and active under the extreme conditions in which they live. Rather than having one basic set of adaptations that works for all environments, Archaea have evolved separate protein features that are customized for each environment. We categorized the Archaea into three general groups to describe what is known about their protein adaptations: thermophilic, psychrophilic, and halophilic. Thermophilic proteins tend to have a prominent hydrophobic core and increased electrostatic interactions to maintain activity at high temperatures. Psychrophilic proteins have a reduced hydrophobic core and a less charged protein surface to maintain flexibility and activity under cold temperatures. Halophilic proteins are characterized by increased negative surface charge due to increased acidic amino acid content and peptide insertions, which compensates for the extreme ionic conditions. While acidophiles, alkaliphiles, and piezophiles are their own class of Archaea, their protein adaptations toward pH and pressure are less discernible. By understanding the protein adaptations used by archaeal extremophiles, we hope to be able to engineer and utilize proteins for industrial, environmental, and biotechnological applications where function in extreme conditions is required for activity.


Assuntos
Adaptação Fisiológica , Archaea/metabolismo , Proteínas Arqueais/metabolismo , Archaea/genética , Proteínas Arqueais/química , Temperatura Baixa , Meio Ambiente , Temperatura Alta , Concentração de Íons de Hidrogênio , Salinidade
4.
Pediatr Ann ; 51(6): e243-e253, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35667098

RESUMO

Nearly 20% of children in the United States have special health care needs, and they often experience disparities in health outcomes. This article reviews barriers to and facilitators of primary pediatric care for children within four defined categories of disability: (1) physical disabilities, both temporary and permanent; (2) chronic conditions requiring accommodations, including mental health conditions; (3) sensory disabilities and conditions; and (4) cognitive, educational, neurodevelopmental, and social disabilities. Primary care facilitators include interventions for both providers and patients that focus on time as a valued resource, provide psychosocial support, coordinate interdisciplinary teams of care, and provide training for providers. Barriers include exclusion of patients with disabilities from research trials and gaps in educational reform regarding ableism and hidden disabilities. Identified facilitators should be implemented on a larger scale, and barriers need to be addressed further so we may better support children with disabilities. [Pediatr Ann. 2022;51(6):e243-e253.].


Assuntos
Pessoas com Deficiência , Pediatria , Criança , Acessibilidade aos Serviços de Saúde , Humanos , Estados Unidos
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