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1.
Environ Sci Technol ; 57(39): 14539-14547, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37729112

RESUMO

Increased interest in greenhouse gas (GHG) emissions, including recent legislative action and voluntary programs, has increased attention on quantifying and ultimately reducing methane emissions from the natural gas supply chain. While inventories used for public or corporate GHG policies have traditionally utilized bottom-up (BU) methods to estimate emissions, the validity of such inventories has been questioned. Therefore, there is attention on utilizing full-facility measurements using airborne, satellite, or drone (top-down (TD)) techniques to inform, improve, or validate inventories. This study utilized full-facility estimates from two independent TD methods at 15 midstream natural gas facilities in the U.S.A., which were compared with a contemporaneous daily inventory assembled by the facility operator, employing comprehensive inventory methods. Estimates from the two TD methods statistically agreed in 2 of 28 paired measurements. Operator inventories, which included extensions to capture sources beyond regular inventory requirements and integration of local measurements, estimated significantly lower emissions than the TD estimates for 40 of 43 paired comparisons. Significant disagreement was observed at most facilities, both between the two TD methods and between the TD estimates and operator inventory. These findings have two implications. First, improving inventory estimates will require additional on-site or ground-based diagnostic screening and measurement of all sources. Second, the TD full-facility measurement methods need to undergo further testing, characterization, and potential improvement specifically tailored for complex midstream facilities.

2.
Blood ; 142(4): 325-335, 2023 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-37216688

RESUMO

Immune thrombotic thrombocytopenic purpura (iTTP) survivors have increased risk of cardiovascular disease, including strokes, and report persistent cognitive difficulties during remission. We conducted this prospective study involving iTTP survivors during clinical remission to determine the prevalence of silent cerebral infarction (SCI), defined as magnetic resonance imaging (MRI) evidence of brain infarction without corresponding overt neurodeficits. We also tested the hypothesis that SCI is associated with cognitive impairment, assessed using the National Institutes of Health ToolBox Cognition Battery. For cognitive assessments, we used fully corrected T scores adjusted for age, sex, race, and education. Based on the diagnostic and statistical manual 5 criteria, we defined mild and major cognitive impairment as T scores with a 1 or 2 standard deviation (SD) and >2 SD below the mean on at least 1 test, respectively. Forty-two patients were enrolled, with 36 completing MRIs. SCI was present in 50% of the patients (18), of which 8 (44.4%) had prior overt stroke including during acute iTTP. Patients with SCI had higher rates of cognitive impairment (66.7% vs 27.7%; P = .026), including major cognitive impairment (50% vs 5.6%; P = .010). In separate logistic regression models, SCI was associated with any (mild or major) cognitive impairment (odds ratio [OR] 10.5 [95% confidence interval (95% CI), 1.45-76.63]; P = .020) and major cognitive impairment (OR 7.98 [95% CI, 1.11-57.27]; P = .039) after adjusting for history of stroke and Beck depression inventory scores. MRI evidence of brain infarction is common in iTTP survivors; the strong association of SCI with impaired cognition suggests that these silent infarcts are neither silent nor innocuous.


Assuntos
Infarto Cerebral , Acidente Vascular Cerebral , Humanos , Infarto Cerebral/diagnóstico por imagem , Infarto Cerebral/epidemiologia , Infarto Cerebral/etiologia , Estudos Prospectivos , Prevalência , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/epidemiologia , Cognição , Infarto Encefálico/diagnóstico por imagem , Infarto Encefálico/epidemiologia , Infarto Encefálico/etiologia , Imageamento por Ressonância Magnética
3.
J Voice ; 2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36959052

RESUMO

OBJECTIVES: Voice care services aim to provide effective and meaningful voice care. Current practice guidance recommends a multidisciplinary voice care approach, supported by the evidence-base and practitioner experience. However, unlike other areas of physical and mental health, current voice care guidance does not explicitly include the voices of experts-by-experience, meaning those who have lived experience of voice difficulties. The perspectives of those working within nonclinical voice professions, such as vocal coaches, are also often omitted. There is therefore a need for updated practice guidance which prioritizes expert-by-experience and nonclinical perspectives. METHODS: Vocal Health Education hosted a consensus meeting in London, UK. The meeting was coproduced with experts-by-experience, and attendees included those with lived experience of voice difficulties and practitioners across a range of disciplines within voice care. The content of the meeting was synthesized into themes and associated recommendations were drafted and agreed to by all attendees. RESULTS: The consensus statement offers practical advice to those working in voice care. Recommendations are offered for multidisciplinary and biopsychosocial voice care, with a focus on person-centered practice and the valuing of lived experience. Through discussion, consensus was reached regarding recommendations for voice care assessment and treatment, practitioner approach, psychosocial considerations, and service design. The need for greater expert-by-experience involvement, coproduction, and co-construction was emphasized throughout. CONCLUSIONS: This report emphasizes the voices of those with lived experience. It highlights ways of updating or improving current care, with the aim of informing clinical practice as well as research and service development. The consensus statement is the first in voice care to include experts-by-experience at the center of its recommendations, underlining the need for more coproduced and co-constructed research and practice within voice healthcare.

4.
Ann Hematol ; 101(10): 2159-2167, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35932324

RESUMO

Pregnancy is a well-established trigger for a first episode or relapse of immune thrombotic thrombocytopenic purpura (iTTP). Other outcomes of subsequent pregnancy after a diagnosis of iTTP are less well described. We conducted this retrospective cohort study to evaluate maternal and fetal outcomes of pregnancy in women with prior iTTP from the Johns Hopkins Thrombotic Microangiopathy Cohort. Of 168 women in the cohort, 102 were of reproductive age at diagnosis. Fourteen pregnancies (in 9 women) that occurred after the initial iTTP episode were included in the analysis. iTTP relapse occurred in 9 (64%) pregnancies. Out of the 9 instances of relapse, 5 relapses occurred in 2 women. Seven pregnancies (50%) ended in fetal death or miscarriage in the setting of iTTP relapse and three were electively terminated due to fear of relapse. Four pregnancies (50% of the 8 that progressed beyond 20 weeks) were complicated by preeclampsia or HELLP syndrome, which is over ten-fold higher than that of the general population. No maternal deaths occurred. Only 4 pregnancies resulted in live births, of which, 2 were pre-term. Pregnancy in women with prior iTTP is associated with a substantial risk of iTTP relapse and fetal loss. Preeclampsia and HELLP syndrome is also more common than that in the general population. ADAMTS13 monitoring and preemptive therapy may improve pregnancy outcomes, which needs to be evaluated prospectively.


Assuntos
Síndrome HELLP , Pré-Eclâmpsia , Púrpura Trombocitopênica Idiopática , Púrpura Trombocitopênica Trombótica , Proteína ADAMTS13 , Feminino , Síndrome HELLP/diagnóstico , Humanos , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/epidemiologia , Gravidez , Púrpura Trombocitopênica Trombótica/diagnóstico , Púrpura Trombocitopênica Trombótica/terapia , Recidiva , Estudos Retrospectivos
5.
6.
Proc Biol Sci ; 283(1840)2016 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-27733543

RESUMO

Larvae of intertidal species develop at sea and must return to adult habitats to replenish populations. Similarly, nutrients, detritus and plankton provide important subsidies spurring growth and reproduction of macroalgae and filter-feeding invertebrates that form the foundation of intertidal communities. Together, these factors determine the density and intensity of interactions among community members. We hypothesized that spatial variation in surfzone hydrodynamics affects the delivery of plankton subsidies. We compared entire zooplankton communities inside and outside the surf zone daily while monitoring physical conditions for one month each at two shores with different surfzone characteristics. Opposite cross-shore distributions of larvae and other zooplankters occurred at the two sites: zooplankton was much more abundant inside the mildly sloping dissipative surf zone (DSZ) with rip currents and was more abundant outside the steep reflective surf zone (RSZ). Biophysical numerical simulations demonstrated that zooplankters were concentrated in rip channels of the DSZ and were mostly unable to enter the RSZ, indicating the hydrodynamic processes behind the observed spatial variation of zooplankters in the surf zone. Differences in the concentration of larvae and other zooplankters between the inner shelf and surf zone may be an underappreciated, key determinant of spatial variation in inshore communities.


Assuntos
Ecossistema , Invertebrados , Plâncton , Alga Marinha , Movimentos da Água , Animais , Cadeia Alimentar , Hidrodinâmica , Larva , Oceanos e Mares , Análise Espacial
7.
Harmful Algae ; 55: 172-178, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-28073530

RESUMO

Most harmful algal blooms (HAB) originate away from the shore and, for them to endanger human health, they must be first transported to shore after which they must enter the surf zone where they can be feed upon by filter feeders. The last step in this sequence, entrance into the surf zone, depends on surf zone hydrodynamics. During two 30-day periods, we sampled Pseudo-nitzschia and particulate domoic acid (pDA) in and offshore of a more dissipative surf zone at Sand City, California (2010) and sampled Pseudo-nitzschia in and out of reflective surf zones at a beach and rocky shores at Carmel River State Beach, California (2011). At Sand City, we measured domoic acid in sand crabs, Emerita analoga. In the more dissipative surf zone, concentrations of Pseudo-nitzschia and pDA were an order of magnitude higher in samples from a rip current than in samples collected just seaward of the surf zone and were 1000 times more abundant than in samples from the shoals separating rip currents. Domoic acid was present in all the Emerita samples and varied directly with the concentration of pDA and Pseudo-nitzschia in the rip current. In the more reflective surf zones, Pseudo-nitzschia concentrations were 1-2 orders of magnitude lower than in samples from 125 and 20m from shore. Surf zone hydrodynamics affects the ingress of Pseudo-nitzschia into surf zones and the exposure of intertidal organisms to HABs on the inner shelf.


Assuntos
Diatomáceas/fisiologia , Monitoramento Ambiental , Ácido Caínico/análogos & derivados , Animais , Anomuros/química , California , Diatomáceas/química , Proliferação Nociva de Algas , Ácido Caínico/análise , Densidade Demográfica , Água do Mar/química , Movimentos da Água
8.
PLoS One ; 10(5): e0125832, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26018804

RESUMO

ß-lactamases are bacterial enzymes that confer resistance to ß-lactam antibiotics, such as penicillins and cephalosporins. There are four classes of ß-lactamase enzymes, each with characteristic sequence and structure properties. Enzymes from class A are the most common and have been well characterized across the family; however, less is known about how physicochemical properties vary across the C and D families. In this report, we compare the dynamical properties of four AmpC (class C) ß-lactamases using our distance constraint model (DCM). The DCM reliably predicts thermodynamic and mechanical properties in an integrated way. As a consequence, quantitative stability/flexibility relationships (QSFR) can be determined and compared across the whole family. The DCM calculates a large number of QSFR metrics. Perhaps the most useful is the flexibility index (FI), which quantifies flexibility along the enzyme backbone. As typically observed in other systems, FI is well conserved across the four AmpC enzymes. Cooperativity correlation (CC), which quantifies intramolecular couplings within structure, is rarely conserved across protein families; however, it is in AmpC. In particular, the bulk of each structure is composed of a large rigid cluster, punctuated by three flexibly correlated regions located at the active site. These regions include several catalytic residues and the Ω-loop. This evolutionary conservation combined with active their site location strongly suggests that these coupled dynamical modes are important for proper functioning of the enzyme.


Assuntos
Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , beta-Lactamases/química , beta-Lactamases/metabolismo , Domínio Catalítico , Cristalografia por Raios X , Modelos Teóricos , Estrutura Secundária de Proteína , Relação Quantitativa Estrutura-Atividade , Termodinâmica
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