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1.
Nature ; 562(7728): 519-525, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30305731

RESUMEN

The food system is a major driver of climate change, changes in land use, depletion of freshwater resources, and pollution of aquatic and terrestrial ecosystems through excessive nitrogen and phosphorus inputs. Here we show that between 2010 and 2050, as a result of expected changes in population and income levels, the environmental effects of the food system could increase by 50-90% in the absence of technological changes and dedicated mitigation measures, reaching levels that are beyond the planetary boundaries that define a safe operating space for humanity. We analyse several options for reducing the environmental effects of the food system, including dietary changes towards healthier, more plant-based diets, improvements in technologies and management, and reductions in food loss and waste. We find that no single measure is enough to keep these effects within all planetary boundaries simultaneously, and that a synergistic combination of measures will be needed to sufficiently mitigate the projected increase in environmental pressures.


Asunto(s)
Agricultura/métodos , Agricultura/tendencias , Ambiente , Abastecimiento de Alimentos , Desarrollo Sostenible , Cambio Climático , Productos Agrícolas/metabolismo , Nitrógeno/metabolismo , Fósforo/metabolismo , Incertidumbre
2.
Artículo en Inglés | MEDLINE | ID: mdl-37742820

RESUMEN

To quantify heat tolerance in insects, two manual observation measures are typically implemented: the time to physiological collapse at a static noxious temperature (time to knockdown; TKD) or the temperature at which collapse occurs as temperature increases (critical thermal maximum; CTmax). Both assay modalities focus on physiological collapse, neglecting the prior behavioral processes. In this study, the locomotion response of Drosophila melanogaster to relatively high temperature (39 and 40.5 °C) was quantified using the TriKinetics Drosophila Activity Monitor (DAM2 system). The absence of locomotion was defined as the state of physiological collapse resulting from extended exposure to high temperature. An easy-to-use executable application that allows the user to automatically extract individual TKD from the activity data was developed. For validation, manual TKD assays were performed in parallel to automated assays across multiple factors, including sex, hardening, recovery time after hardening, and assay temperature, which gave similar results. In terms of behavioral aspects, heat hardening consistently led to reduced activity during a subsequent heat stress, irrespective of assay temperature, sex, or recovery time after hardening. Our automated heat tolerance assay utilizing the DAM2 system is one way to expand the scope of the heat tolerance phenotype to include a behavioral component in conjunction with the traditional TKD measure.


Asunto(s)
Termotolerancia , Animales , Drosophila melanogaster/genética , Calor , Fenotipo , Drosophila
3.
AIDS Behav ; 26(10): 3199-3209, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35364730

RESUMEN

During 2007-2019, the percentage of HIV Outpatient Study participants reporting anal or vaginal condomless sex in the past 6 months ranged from a low of 17% among heterosexual males to 59% for men who have sex with men (MSM). MSM reported having had condomless sex more frequently than heterosexual males and females and were the only group in which an increase in condomless sex was observed during the study period (from 39 to 59%). Although persons with undetectable HIV viral load have effectively no risk of transmitting HIV sexually (U = U), there is still the potential risk of transmission or acquisition of other sexually transmitted infections (STIs) when engaging in condomless sex. Continuing education about risks of HIV and STI transmission as well as ongoing screening for and treatment of STIs, retention in HIV treatment, and support for sexual health are critical components of care for people living with HIV.


Asunto(s)
Infecciones por VIH , Minorías Sexuales y de Género , Enfermedades de Transmisión Sexual , Condones , Femenino , Infecciones por VIH/diagnóstico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Homosexualidad Masculina , Humanos , Masculino , Pacientes Ambulatorios , Conducta Sexual , Enfermedades de Transmisión Sexual/diagnóstico , Sexo Inseguro
4.
Bioscience ; 71(10): 1079-1090, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34616238

RESUMEN

A growing number of companies have announced zero-deforestation commitments (ZDCs) to eliminate commodities produced at the expense of forests from their supply chains. Translating these aspirational goals into forest conservation requires forest mapping and monitoring (M&M) systems that are technically adequate and therefore credible, salient so that they address the needs of decision makers, legitimate in that they are fair and unbiased, and scalable over space and time. We identify 12 attributes of M&M that contribute to these goals and assess how two prominent ZDC programs, the Amazon Soy Moratorium and the High Carbon Stock Approach, integrate these attributes into their M&M systems. These programs prioritize different attributes, highlighting fundamental trade-offs in M&M design. Rather than prescribe a one-size-fits-all solution, we provide policymakers and practitioners with guidance on the design of ZDC M&M systems that fit their specific use case and that may contribute to more effective implementation of ZDCs.

5.
Proc Natl Acad Sci U S A ; 115(1): 121-126, 2018 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-29229857

RESUMEN

Many major corporations and countries have made commitments to purchase or produce only "sustainable" palm oil, a commodity responsible for substantial tropical forest loss. Sustainability certification is the tool most used to fulfill these procurement policies, and around 20% of global palm oil production was certified by the Roundtable on Sustainable Palm Oil (RSPO) in 2017. However, the effect of certification on deforestation in oil palm plantations remains unclear. Here, we use a comprehensive dataset of RSPO-certified and noncertified oil palm plantations (∼188,000 km2) in Indonesia, the leading producer of palm oil, as well as annual remotely sensed metrics of tree cover loss and fire occurrence, to evaluate the impact of certification on deforestation and fire from 2001 to 2015. While forest loss and fire continued after RSPO certification, certified palm oil was associated with reduced deforestation. Certification lowered deforestation by 33% from a counterfactual of 9.8 to 6.6% y-1 Nevertheless, most plantations contained little residual forest when they received certification. As a result, by 2015, certified areas held less than 1% of forests remaining within Indonesian oil palm plantations. Moreover, certification had no causal impact on forest loss in peatlands or active fire detection rates. Broader adoption of certification in forested regions, strict requirements to avoid all peat, and routine monitoring of clearly defined forest cover loss in certified and RSPO member-held plantations appear necessary if the RSPO is to yield conservation and climate benefits from reductions in tropical deforestation.


Asunto(s)
Conservación de los Recursos Naturales , Producción de Cultivos , Magnoliopsida/crecimiento & desarrollo , Aceite de Palma , Incendios Forestales , Indonesia
6.
Acta Virol ; 65(4): 381-389, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34796712

RESUMEN

Nora virus is a RNA picorna-like virus that produces a persistent infection in Drosophila melanogaster. The genome is approximately 12,300 bases and is divided into four open reading frames (ORFs). Structurally, there are four important viral proteins: VP3, VP4A, VP4B, and VP4C. Three proteins (VP4A, VP4B, and VP4C) that form the virion's capsid are encoded by ORF 4, which produces a polyprotein that is post-translationally cleaved. The fourth protein (VP3) is encoded by ORF 3 and it is hypothesized to play a role in virion stability. The genes for these proteins were individually cloned into Escherichia coli, expressed, and the proteins were purified. Virus-like particles (VLPs) were assembled in vitro by mixing the proteins together in different combinations and measured via electron microscopy. Assemblies that contained VP4A and/or VP3 created VLPs with similar sizes to purified empty Nora virus capsids, potentially indicating that VP4A and/or VP3 are vital for Nora virus capsid structure, assembly, and/or stability. Not only does this study provide insight into the role of Nora virus proteins, but it may also lead to a deeper understanding of how Nora virus or other picorna-like viruses undergo assembly.  Keywords: RNA viruses; Nora virus; picorna-like virus; virus-like particles; capsid assembly.


Asunto(s)
Drosophila melanogaster , Virus ARN , Animales , Cápside , Proteínas de la Cápside/genética , Infección Persistente , Virión/genética , Ensamble de Virus
7.
J Fluoresc ; 30(5): 977-983, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32761419

RESUMEN

A reaction-based sensor (NAS-1) showed a high affinity and sensitivity to HSO3- via a nucleophilic addition reaction in the aqueous media, giving dual signals from absorption and emission spectra. NAS-1 was successfully applied in RK13 epithelial cells to detect HSO3- in a cellular environment.


Asunto(s)
Colorantes Fluorescentes/química , Naftalimidas/química , Sulfitos/análisis , Animales , Células Cultivadas , Colorantes Fluorescentes/síntesis química , Estructura Molecular , Naftalimidas/síntesis química , Imagen Óptica , Conejos , Espectrometría de Fluorescencia
8.
Ann Neurol ; 77(4): 710-9, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25627340

RESUMEN

OBJECTIVE: The Veterans Administration Cooperative Studies Program #468, a multicenter study that randomized Parkinson's disease (PD) patients to either subthalamic nucleus (STN) or globus pallidus internus (GPi) deep brain stimulation (DBS), found that stimulation at either target provided similar overall motoric benefits. We conducted an additional analysis of this data set to evaluate whether PD motor subtypes responded differently to the 2 stimulation targets. METHODS: We classified 235 subjects by motor subtype: tremor dominant (TD), intermediate (I), or postural instability gait difficulty (PIGD), based on pre-DBS baseline Unified Parkinson's Disease Rating Scale (UPDRS) scores off-medication. The primary outcome was change in UPDRS part III (UPDRS-III) off-medication scores from baseline to 24 months post-DBS, compared among subjects with particular PD motor subtypes and by DBS target (STN vs GPi). Changes in tremor, rigidity, akinesia, and gait scores were also assessed using the UPDRS. RESULTS: TD patients had greater mean overall motor improvement, measured by UPDRS-III, after GPi DBS, compared to STN DBS (17.5 ± 13.0 vs 14.6 ± 14.9, p = 0.02), with improvement in gait accounting for this difference. Regardless of stimulation target, PIGD subjects had lower mean overall improvement in UPDRS-III scores compared with I or TD subjects (8.7 ± 12.2 vs 21.7 ± 11.2 vs 16.3 ± 13.8, p = 0.001). INTERPRETATION: Our results suggest that responsiveness to both GPi and STN DBS is similar among different PD motor subtypes, although the TD motor subtype may have a greater response to GPi DBS with respect to gait. PIGD patients obtained less overall benefit from stimulation.


Asunto(s)
Estimulación Encefálica Profunda/métodos , Globo Pálido , Enfermedad de Parkinson/clasificación , Enfermedad de Parkinson/terapia , Núcleo Subtalámico , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/diagnóstico , Método Simple Ciego , Resultado del Tratamiento
9.
Glob Chang Biol ; 22(10): 3383-94, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27185532

RESUMEN

With increasing nitrogen (N) application to croplands required to support growing food demand, mitigating N2 O emissions from agricultural soils is a global challenge. National greenhouse gas emissions accounting typically estimates N2 O emissions at the country scale by aggregating all crops, under the assumption that N2 O emissions are linearly related to N application. However, field studies and meta-analyses indicate a nonlinear relationship, in which N2 O emissions are relatively greater at higher N application rates. Here, we apply a super-linear emissions response model to crop-specific, spatially explicit synthetic N fertilizer and manure N inputs to provide subnational accounting of global N2 O emissions from croplands. We estimate 0.66 Tg of N2 O-N direct global emissions circa 2000, with 50% of emissions concentrated in 13% of harvested area. Compared to estimates from the IPCC Tier 1 linear model, our updated N2 O emissions range from 20% to 40% lower throughout sub-Saharan Africa and Eastern Europe, to >120% greater in some Western European countries. At low N application rates, the weak nonlinear response of N2 O emissions suggests that relatively large increases in N fertilizer application would generate relatively small increases in N2 O emissions. As aggregated fertilizer data generate underestimation bias in nonlinear models, high-resolution N application data are critical to support accurate N2 O emissions estimates.


Asunto(s)
Clima , Productos Agrícolas , África del Sur del Sahara , Europa Oriental , Fertilizantes , Dióxido de Nitrógeno , Óxido Nitroso
10.
Proc Natl Acad Sci U S A ; 109(19): 7559-64, 2012 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-22523241

RESUMEN

Industrial agricultural plantations are a rapidly increasing yet largely unmeasured source of tropical land cover change. Here, we evaluate impacts of oil palm plantation development on land cover, carbon flux, and agrarian community lands in West Kalimantan, Indonesian Borneo. With a spatially explicit land change/carbon bookkeeping model, parameterized using high-resolution satellite time series and informed by socioeconomic surveys, we assess previous and project future plantation expansion under five scenarios. Although fire was the primary proximate cause of 1989-2008 deforestation (93%) and net carbon emissions (69%), by 2007-2008, oil palm directly caused 27% of total and 40% of peatland deforestation. Plantation land sources exhibited distinctive temporal dynamics, comprising 81% forests on mineral soils (1994-2001), shifting to 69% peatlands (2008-2011). Plantation leases reveal vast development potential. In 2008, leases spanned ∼65% of the region, including 62% on peatlands and 59% of community-managed lands, yet <10% of lease area was planted. Projecting business as usual (BAU), by 2020 ∼40% of regional and 35% of community lands are cleared for oil palm, generating 26% of net carbon emissions. Intact forest cover declines to 4%, and the proportion of emissions sourced from peatlands increases 38%. Prohibiting intact and logged forest and peatland conversion to oil palm reduces emissions only 4% below BAU, because of continued uncontrolled fire. Protecting logged forests achieves greater carbon emissions reductions (21%) than protecting intact forests alone (9%) and is critical for mitigating carbon emissions. Extensive allocated leases constrain land management options, requiring trade-offs among oil palm production, carbon emissions mitigation, and maintaining community landholdings.


Asunto(s)
Arecaceae/crecimiento & desarrollo , Carbono/metabolismo , Conservación de los Recursos Naturales/métodos , Ecosistema , Árboles/crecimiento & desarrollo , Agricultura/métodos , Agricultura/tendencias , Arecaceae/metabolismo , Borneo , Conservación de los Recursos Naturales/tendencias , Monitoreo del Ambiente/métodos , Geografía , Aceite de Palma , Aceites de Plantas/metabolismo
11.
J Investig Med ; : 10815589241252592, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38666457

RESUMEN

This article aimed at analyzing the acute impact and the longer-term recovery of COVID-19 pandemic effects on clinical encounter types, HIV viral load (VL) testing, and suppression (HIV VL < 200 copies/mL). This study was a longitudinal cohort study of participants seen during 2019-2022 at nine HIV Outpatient Study (HOPS) sites. Generalized linear mixed models (GLMMs) estimated monthly rates of all encounters, office and telemedicine visits, and HIV VL tests using 2010-2022 data. We examined factors associated with nonsuppressed VL (VL ≥ 200 copies/mL) and not having ambulatory care visits during the pandemic using GLMM for logistic regression with 2017-2022 and 2019-2022 data, respectively. Of 2351 active participants, 76.0% were male, 57.6% aged ≥ 50 years, 40.7% non-Hispanic White, 38.2% non-Hispanic Black, 17.3% Hispanic/Latino, and 51.0% publicly insured. The monthly rates of in-person and telemedicine visits varied during 2020 through mid-year 2022. Multivariable logistic regression showed that persons with no encounters were more likely to be male or have VL ≥ 200 copies/mL. For participants with ≥1 VL test, the prevalence rate of HIV VL ≥ 200 copies/mL during 2020 was close to the rates from 2014 to 2019. The change in probability of viral suppression was not associated with participant's age, sex, race/ethnicity, or insurance type. In the HOPS, overall patient encounters declined over 2 years during the pandemic with variations in telemedicine and in-person events, with relative maintenance of viral suppression. Ongoing recovery from the impact of COVID-19 on ambulatory care will require continued efforts to improve retention and patient access to medical services.

12.
Curr Oncol ; 31(8): 4781-4794, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39195341

RESUMEN

The United States Veterans Affairs (VA) Health Care System has a strong history of conducting impactful oncology randomized clinical trials (RCTs). We developed a phase II/III RCT to test the use of metastasis-directed therapy in Veterans with oligometastatic prostate cancer (OMPC)-the first VA RCT in OMPC that leverages novel imaging and advanced radiotherapy techniques. To accomplish this, we developed a clinical trial network to conduct the study. In this manuscript, we describe several challenges we encountered in study development/conduct and our strategies to address them, with the goal of helping investigators establish robust study networks to conduct clinical trials. In the study start-up, we encountered challenges in timely site activation, and leveraged project management to maximize efficiency. Additionally, there were several changes in the clinical paradigms in imaging and treatment that led to protocol amendments to ensure maximum equipoise, recruitment, and impact of the study. Specifically, we amended the trial to add de novo OMPC patients (from initially only recurrent OMPC) and expanded the study to allow up to 10 metastases (from initially five). Finally, in order to maintain local study team engagement, we developed initiatives to maximize collaboration and add value to the overall clinical program through study participation.


Asunto(s)
United States Department of Veterans Affairs , Humanos , Estados Unidos , Masculino , Oncología Médica/métodos , Neoplasias de la Próstata/terapia , Veteranos , Ensayos Clínicos como Asunto
13.
J Neurol Neurosurg Psychiatry ; 84(10): 1113-8, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23667214

RESUMEN

BACKGROUND: The risk of suicide behaviours post-deep brain stimulation (DBS) surgery in Parkinson's disease (PD) remains controversial. We assessed if suicide ideation and behaviours are more common in PD patients (1) randomised to DBS surgery versus best medical therapy (BMT); and (2) randomised to subthalamic nucleus (STN) versus globus pallidus interna (GPi) DBS surgery. METHODS: In Phase 1 of the Veterans Affairs CSP 468 study, 255 PD patients were randomised to DBS surgery (n=121) or 6 months of BMT (n=134). For Phase 2, a total of 299 patients were randomised to STN (n=147) or GPi (n=152) DBS surgery. Patients were assessed serially with the Unified Parkinson's Disease Rating Scale Part I depression item, which queries for suicide ideation; additionally, both suicide behaviour adverse event data and proxy symptoms of increased suicide risk from the Parkinson's Disease Questionnaire (PDQ-39) and the Short Form Health Survey (SF-36) were collected. RESULTS: In Phase 1, no suicide behaviours were reported, and new-onset suicide ideation was rare (1.9% for DBS vs 0.9% for BMT; Fisher's exact p=0.61). Proxy symptoms of relevance to suicide ideation were similar in the two groups. Rates of suicide ideation at 6 months were similar for patients randomised to STN versus GPi DBS (1.5% vs 0.7%; Fisher's exact p=0.61), but several proxy symptoms were worse in the STN group. CONCLUSIONS: Results from the randomised, controlled phase of a DBS surgery study in PD patients do not support a direct association between DBS surgery and an increased risk for suicide ideation and behaviours.


Asunto(s)
Globo Pálido/fisiopatología , Enfermedad de Parkinson/psicología , Enfermedad de Parkinson/terapia , Núcleo Subtalámico/fisiopatología , Ideación Suicida , Intento de Suicidio/psicología , Suicidio/psicología , Anciano , Estimulación Encefálica Profunda , Trastorno Depresivo/diagnóstico , Trastorno Depresivo/fisiopatología , Trastorno Depresivo/psicología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/fisiopatología
14.
J Acquir Immune Defic Syndr ; 92(1): 67-75, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36150045

RESUMEN

BACKGROUND: The timing and magnitude of antiretroviral therapy-associated weight change attributions are unclear. SETTING: HIV Outpatient Study participants. METHODS: We analyzed 2007-2018 records of virally suppressed (VS) persons without integrase inhibitor (INSTI) experience who switched to either INSTI-based or another non-INSTI-based ART, and remained VS. We analyzed BMI changes using linear mixed models, INSTI- and tenofovir alafenamide (TAF) contributions to BMI change by linear mixed models-estimated slopes, and BMI inflection points. RESULTS: Among 736 participants (5316 person-years), 441 (60%) switched to INSTI-based ART; the remainder to non-INSTI-based ART. The mean follow-up was 7.15 years for INSTI recipients and 7.35 years for non-INSTI. Preswitch, INSTI and non-INSTI groups had similar median BMI (26.3 versus 25.9 kg/m 2 , P = 0.41). INSTI regimens included raltegravir (178), elvitegravir (112), and dolutegravir (143). Monthly BMI increases postswitch were greater with INSTI than non-INSTI (0.0525 versus 0.006, P < 0.001). A BMI inflection point occurred 8 months after switch among INSTI users; slopes were similar regardless of TAF use immediately postswitch. Among INSTI + TAF users, during 8 months postswitch, 87% of BMI slope change was associated with INSTI use, 13% with TAF use; after 8 months, estimated contributions were 27% and 73%, respectively. For non-INSTI+TAF, 84% of BMI gain was TAF-associated consistently postswitch. Persons switching from TDF to TAF had greater BMI increases than others ( P < 0.001). CONCLUSION: Among VS persons who switched ART, INSTI and TAF use were independently associated with BMI increases. During 8 months postswitch, BMI changes were greatest and most associated with INSTI use; afterward, gradual BMI gain was largely TAF-associated.


Asunto(s)
Infecciones por VIH , Inhibidores de Integrasa , Humanos , Infecciones por VIH/tratamiento farmacológico , Aumento de Peso
15.
AIDS Res Treat ; 2023: 4423132, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38078054

RESUMEN

Current U.S. guidelines recommend integrase strand transfer inhibitor (INSTI)-based antiretroviral therapy (ART) as initial treatment for people with HIV (PWH). We assessed long-term effects of INSTI use on lipid profiles in routine HIV care. We analyzed medical record data from the HIV Outpatient Study's participants in care from 2007 to 2021. Hyperlipidemia was defined based on clinical diagnoses, treatments, and laboratory results. We calculated hyperlipidemia incidence rates and rate ratios (RRs) during initial ART and assessed predictors of incident hyperlipidemia by using Poisson regression. Among 349 eligible ART-naïve PWH, 168 were prescribed INSTI-based ART (36 raltegravir (RAL), 51 dolutegravir (DTG), and 81 INSTI-others (elvitegravir and bictegravir)) and 181 non-INSTI-based ART, including 68 protease inhibitor (PI)-based ART. During a median follow-up of 1.4 years, hyperlipidemia rates were 12.8, 22.3, 22.7, 17.4, and 12.6 per 100 person years for RAL-, DTG-, INSTI-others-, non-INSTI-PI-, and non-INSTI-non-PI-based ART, respectively. In multivariable analysis, compared with the RAL group, hyperlipidemia rates were higher in INSTI-others (RR = 2.25; 95% confidence interval (CI): 1.29-3.93) and non-INSTI-PI groups (RR = 1.89; CI: 1.12-3.19) but not statistically higher for the DTG (RR = 1.73; CI: 0.95-3.17) and non-INSTI-non-PI groups (RR = 1.55; CI: 0.92-2.62). Other factors independently associated with hyperlipidemia included older age, non-Hispanic White race/ethnicity, and ART without tenofovir disoproxil fumarate. PWH using RAL-based regimens had lower rates of incident hyperlipidemia than PWH receiving non-INSTI-PI-based ART but had similar rates as those receiving DTG-based ART, supporting federal recommendations for using DTG-based regimens as the initial therapy for ART-naïve PWH.

16.
J Phys Chem A ; 116(41): 10122-34, 2012 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-22984979

RESUMEN

Particle formation and growth with H(2)SO(4) molecules in an axially symmetric flow reactor was simulated with computational fluid dynamics. A warm (~310 K) gas containing H(2)SO(4) flows into a cooled section (296 K) that induces particle formation. The fluid dynamics gives flow fields, temperatures, and reactant and cluster distributions. Particle formation and growth are simulated with detailed H(2)SO(4) cluster kinetics with chemistry based on measured small cluster thermodynamics and on bulk thermodynamics for large clusters. Results show that particle number densities have power law dependencies on sulfuric acid of ~7, in accord with the thermodynamics of the cluster chemistry. The region where particle formation rates are largest has a temperature that is within 3 K of the wall. Additional simulations show that the H(2)SO(4) concentration in this region is 5 to 10 times greater than the measured H(2)SO(4): this information allows for direct comparisons of experiment and theory. Experiments where ammonia was added as a third nucleating species were simulated with a three-dimensional model. Ammonia was dispersed quickly and particle formation during this mixing was seen to be low. Downstream of the initial mixing region, however, ammonia greatly affected particle formation.


Asunto(s)
Simulación de Dinámica Molecular , Ácidos Sulfúricos/química , Termodinámica , Cinética
17.
Nat Commun ; 13(1): 5476, 2022 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-36115865

RESUMEN

Zero-deforestation supply chain policies that leverage the market power of commodity buyers to change agricultural producer behavior can reduce forest clearing in regions with rapid commodity expansion and weak forest governance. Yet leakage-when deforestation is pushed to other regions-may dilute the global effectiveness of regionally successful policies. Here we show that domestic leakage offsets 43-50% of the avoided deforestation induced by existing and proposed zero-deforestation supply chain policies in Brazil's soy sector. However, cross-border leakage is insignificant (<3%) because soybean production is displaced to existing U.S. farmland. Eliminating deforestation from the supply chains of all firms exporting Brazilian soy to the EU or China from 2011-2016 could have reduced net global deforestation by 2% and Brazilian deforestation by 9%. Thus, if major tropical commodity importers (e.g., the EU) require traders to eliminate deforestation from their supply chains, it could help bend the curve on global forest loss.


Asunto(s)
Conservación de los Recursos Naturales , Glycine max , Agricultura , Brasil , Bosques
18.
J Womens Health (Larchmt) ; 31(1): 38-46, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-33844948

RESUMEN

Background: In this opioid overdose epidemic, women are an overlooked group seeing increasing rates of overdose death. Implementation challenges have prevented evidence-based interventions from effectively reaching women who misuse opioids, with gaps in access to effective treatment and services. Family planning clinics could serve as important points of contact for referral to needed treatments and services. The study explores how family planning staff knowledge and attitudes related to opioid misuse serve as potential barriers and challenges in making referrals for evidence-based services and treatments. Methods: In 2018, we conducted a national online survey of family planning staff, assessing knowledge and attitudes of treatments and services for opioid misuse. Results: A total of 691 family planning staff completed the survey. Most respondents agreed that opioid misuse was a major problem in their community (86.0%) and identified challenges in responding to it, including a lack of treatment access (70.3%), the absence of in-house behavioral health staff (67.2%), and unfamiliarity with local treatment providers (54.1%). Respondents reported low levels of acceptability for syringe services programs (46.0%), medications such as methadone and buprenorphine (55.4%), and naloxone to reverse opioid overdose (60.1%). Controlling for other factors, race/ethnicity, urbanicity, workplace role, and substance use training were associated with differences in acceptability. Conclusions: Family planning settings could play a critical role in connecting women who misuse opioids to treatment and services. Strategies are needed to increase the acceptability of evidence-based interventions and the feasibility of having family planning staff play a linkage role.


Asunto(s)
Buprenorfina , Trastornos Relacionados con Opioides , Analgésicos Opioides/uso terapéutico , Buprenorfina/uso terapéutico , Servicios de Planificación Familiar , Femenino , Humanos , Naloxona/uso terapéutico , Trastornos Relacionados con Opioides/tratamiento farmacológico , Derivación y Consulta
19.
Data Brief ; 42: 108120, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35434225

RESUMEN

Cerner Real-World Data TM (CRWD) is a de-identified big data source of multicenter electronic health records. Cerner Corporation secured appropriate data use agreements and permissions from more than 100 health systems in the United States contributing to the database as of March 2022. A subset of the database was extracted to include data from only patients with SARS-CoV-2 infections and is referred to as the Cerner COVID-19 Dataset. The December 2021 version of CRWD consists of 100 million patients and 1.5 billion encounters across all care settings. There are 2.3 billion, 2.9 billion, 486 million, and 11.5 billion records in the condition, medication, procedure, and lab (laboratory test) tables respectively. The 2021 Q3 COVID-19 Dataset consists of 130.1 million encounters from 3.8 million patients. The size and longitudinal nature of CRWD can be leveraged for advanced analytics and artificial intelligence in medical research across all specialties and is a rich source of novel discoveries on a wide range of conditions including but not limited to COVID-19.

20.
AIDS Res Hum Retroviruses ; 38(7): 519-529, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35451335

RESUMEN

Attention to non-AIDS comorbidities is increasingly important in the HIV care and management in the United States. We sought to assess comorbidities before and after antiretroviral therapy (ART) initiation among persons with HIV (PWH). Using the 2008-2018 HIV Outpatient Study (HOPS) data, we assessed changes in prevalence of physical and psychiatric comorbidities, by sex, among participants initiating ART. Cox proportional hazards models were fit to investigate factors associated with the first documented occurrence of key comorbidities, adjusting for demographics and other covariates, including insurance type, CD4+ cell count, ART regimen, and smoking status. Among 1,236 participants who initiated ART (median age 36 years, CD4 cell count 375 cells/mm3), 79% were male, 66% non-white, 44% publicly insured, 53% ever smoked, 33% had substance use history, and 22% had body mass index ≥30 kg/m2. Among females, the percentages with at least one condition were: at ART start, 72% had a physical and 42% a psychiatric comorbidity, and after a median of 6.1 years of follow-up, these were 87% and 63%, respectively. Among males, the percentages with at least one condition were: at ART start, 61% had a physical and 32% a psychiatric comorbidity, and after a median of 4.6 years of follow-up, these were 82% and 53%, respectively. In multivariable Cox proportional hazards analyses, increasing age and higher viral loads (VL) were associated with most physical comorbidities, and being a current/former smoker and higher VL were associated with all psychiatric comorbidities analyzed. HOPS participants already had a substantial burden of physical and psychiatric comorbidities at the time of ART initiation. With advancing age, PWH who initiate ART experience a clinically significant increase in the burden of chronic non-HIV comorbidities that warrants continued surveillance, prevention, and treatment.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Adulto , Fármacos Anti-VIH/uso terapéutico , Recuento de Linfocito CD4 , Comorbilidad , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Humanos , Masculino , Pacientes Ambulatorios , Estados Unidos/epidemiología , Carga Viral
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