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1.
Carbon Balance Manag ; 19(1): 26, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39143325

RESUMEN

BACKGROUND: Forests are significant terrestrial biomes for carbon storage, and annual carbon accumulation of forest biomass contributes offsets affecting net greenhouse gases in the atmosphere. The immediate loss of stored carbon through fire on forest lands reduces the annual offsets provided by forests. As such, the United States reporting includes annual estimates of direct fire emissions in conjunction with the overall forest stock and change estimates as a part of national greenhouse gas inventories within the United Nations Framework Convention on Climate Change. Forest fire emissions reported for the United States, such as the 129 Tg CO2 reported for 2022, are based on the Wildland Fire Emissions Inventory System (WFEIS). Current WFEIS estimates are included in the Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2022 published in 2024 by the United States Environmental Protection Agency. Here, we describe WFEIS the fire emissions inventory system we used to address current information needs, and an analysis to confirm compatibility of carbon mass between estimated forest fire emissions and carbon in forest stocks. RESULTS: The summaries of emissions from forests are consistent with previous reports that show rates and interannual variability in emissions and forest land area burned are generally greater in recent years relative to the 1990s. Both emissions and interannual variability are greater in the western United States. The years with the highest CO2 emissions from forest fires on the 48 conterminous states plus Alaska were 2004, 2005, and 2015. In some years, Alaska emissions exceed those of the 48 conterminous states, such as in 2022, for example. Comparison of forest fire emission to forest carbon stocks indicate there is unlikely any serious disconnect between inventory and fire emissions estimates. CONCLUSIONS: The WFEIS system is a user-driven approach made available via a web browser. Model results are compatible with the scope and reporting needs of the annual national greenhouse gas inventories.

2.
Carbon Balance Manag ; 19(1): 25, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39143377

RESUMEN

BACKGROUND: Wood carbon fractions (CFs)-the proportion of dry woody biomass comprised of elemental carbon (C)-are a key component of forest C estimation protocols and studies. Traditionally, a wood CF of 50% has been assumed in forest C estimation protocols, but recent studies have specifically quantified differences in wood CFs across several different forest biomes and taxonomic divisions, negating the need for generic wood CF assumptions. The Intergovernmental Panel on Climate Change (IPCC), in its 2006 "Guidelines for National Greenhouse Gas Inventories", published its own multitiered system of protocols for estimating forest C stocks, which included wood CFs that (1) were based on the best available literature (at the time) and (2) represented a significant improvement over the generic 50% wood CF assumption. However, a considerable number of new studies on wood CFs have been published since 2006, providing more accurate, robust, and spatially- and taxonomically- specific wood CFs for use in forest C estimation. MAIN TEXT: We argue that the IPCC's recommended wood CFs and those in many other forest C estimation models and protocols (1) differ substantially from, and are less robust than, wood CFs derived from recently published data-rich studies; and (2) may lead to nontrivial errors in forest C estimates, particularly for countries that rely heavily on Tier 1 forest C methods and protocols (e.g., countries of the Global South with large expanses of tropical forests). Based on previous studies on this topic, we propose an alternative set of refined wood CFs for use in multiscale forest C estimation, and propose a novel decision-making framework for integrating species- and location-specific wood CFs into forest C estimation models. CONCLUSION: The refined wood CFs that we present in this commentary may be used by the IPCC to update its recommended wood CFs for use in forest C estimation. Additionally, we propose a novel decision-making framework for integrating data-driven wood CFs into a wider suite of multitiered forest C estimation protocols, models, and studies.

3.
BMC Prim Care ; 25(1): 285, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39103760

RESUMEN

BACKGROUND: Primary care is often described as slow to change. But conceptualized through complexity theory, primary care is continually changing in unpredictable, non-linear ways through self-organization processes. Self-organization has proven hard to study directly. We aimed to develop a methodology to study self-organization and describe how a primary care clinic self-organizes over time. METHODOLOGY: We completed a virtual case study of an urban primary care clinic from May-Nov 2021, applying methodological insights from actor-network theory to examine the complexity theory concept of self-organization. We chose to focus our attention on self-organization activities that alter organizational routines. Data included fieldnotes of observed team meetings, document collection, interviews with clinic members, and notes from brief weekly discussions to detect actions to change clinical and administrative routines. Adapting schema analysis, we described changes to different organizational routines chronologically, then explored intersecting changes. We sought feedback on results from the participating clinic. FINDINGS: Re-establishing equilibrium remained challenging well into the COVID-19 pandemic. The primary care clinic continued to self-organize in response to changing health policies, unintended consequences of earlier adaptations, staff changes, and clinical care initiatives. Physical space, technologies, external and internal policies, guidelines, and clinic members all influenced self-organization. Changing one created ripple effects, sometimes generating new, unanticipated problems. Member checking confirmed we captured most of the changes to organizational routines during the case study period. CONCLUSIONS: Through insights from actor-network theory, applied to studying actions taken that alter organizational routines, it is possible to operationalize the theoretical construct of self-organization. Our methodology illuminates the primary care clinic as a continually changing entity with co-existing and intersecting processes of self-organization in response to varied change pressures.


Asunto(s)
COVID-19 , Atención Primaria de Salud , Humanos , COVID-19/epidemiología , Atención Primaria de Salud/organización & administración , Canadá/epidemiología , Pandemias , Innovación Organizacional , SARS-CoV-2 , Estudios de Casos Organizacionales
4.
bioRxiv ; 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39149402

RESUMEN

Biotechnological processes hold tremendous potential for the efficient and sustainable conversion of one-carbon (C1) substrates into complex multi-carbon products. However, the development of robust and versatile biocatalytic systems for this purpose remains a significant challenge. In this study, we report a hybrid electrochemical-biochemical cell-free system for the conversion of C1 substrates into the universal biological building block acetyl-CoA. The synthetic reductive formate pathway (ReForm) consists of five core enzymes catalyzing non-natural reactions that were established through a cell-free enzyme engineering platform. We demonstrate that ReForm works in a plug-and-play manner to accept diverse C1 substrates including CO2 equivalents. We anticipate that ReForm will facilitate efforts to build and improve synthetic C1 utilization pathways for a formate-based bioeconomy.

6.
J Speech Lang Hear Res ; 67(8): 2600-2619, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-38995869

RESUMEN

PURPOSE: A picture naming test is presented that reveals impairment to specific mechanisms involved in the naming process, using accuracy scores on curated item sets. A series of psychometric validation experiments are reported. METHOD: Using a computational model that enables estimation of item difficulty at the lexical and sublexical stages of word retrieval, two complimentary sets of items were constructed that challenge the respective psycholinguistic levels of representation. The difference in accuracy between these item sets yields the relative linguistic impairment (RLI) score. In a cohort of 91 people with chronic left-hemisphere stroke who enrolled in a clinical trial for anomia, we assessed psychometric properties of the RLI score and then used the new scale to make predictions about other language behaviors, lesion distributions, and functional activation during naming. RESULTS: RLI scores had adequate psychometric properties for clinical significance. RLI scores contained predictive information about spontaneous speech fluency, over and above accuracy. A dissociation was observed between performance on the RLI item sets and performance on the subtests of an independent language battery. Sublexical RLI was significantly associated with apraxia of speech and with lesions encompassing perisylvian regions, while lexical RLI was associated with lesions to deep white matter. The RLI construct was reflected in functional brain activity during naming, independent of overall accuracy, with a respective shift of activation between dorsal and ventral networks responsible for different aspects of word retrieval. CONCLUSION: The RLI assessment satisfies the psychometric requirements to serve as a useful clinical measure.


Asunto(s)
Pruebas del Lenguaje , Psicometría , Accidente Cerebrovascular , Humanos , Femenino , Masculino , Persona de Mediana Edad , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/psicología , Accidente Cerebrovascular/fisiopatología , Anciano , Anomia/diagnóstico , Anomia/psicología , Adulto , Lingüística , Simulación por Computador
8.
Front Psychiatry ; 15: 1169686, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38979507

RESUMEN

Background: Hypertension is a major source of morbidity and mortality worldwide, particularly for racial and ethnic minorities who face higher rates of hypertension and worse health-related outcomes. Recent research has reported on protective associations between classic psychedelics and hypertension; however, there is a need to explore how race and ethnicity may moderate such associations. Methods: We used data from the National Survey on Drug Use and Health (2005-2014) to assess whether race and ethnicity moderate the associations between classic psychedelic use - specifically psilocybin - and past year hypertension. Results: Hispanic identity moderated the associations between psilocybin use and past year hypertension. Furthermore, individuals who used psilocybin and identified as Non-Hispanic White had reduced odds of hypertension (aOR: 0.83); however, these associations were not observed for any other racial or ethnic groups in our study for individuals who used psilocybin. Conclusion: Overall, our results demonstrate that the associations between psychedelics and hypertension may vary by race and ethnicity. Longitudinal studies and clinical trials can further advance this research and determine whether such differences exist in causal contexts. Project registration: https://osf.io/xsz2p/?view_only=0bf7b56749034c18abb2a3f8d3d4bc0b.

9.
J Funct Morphol Kinesiol ; 9(2)2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38921641

RESUMEN

The fire service suffers from high rates of cardiovascular disease and poor overall health, and firefighters often suffer fatal and non-fatal injuries while on the job. Most fatal injuries result from sudden cardiac death, while non-fatal injuries are to the musculoskeletal system. Previous works suggest a mechanistic link between several health and performance variables and injury risk. In addition, studies have suggested physical activity and nutrition can improve overall health and occupational performance. This review offers practical applications for exercise via feasible training modalities as well as nutritional recommendations that can positively impact performance on the job. Time-efficient training modalities like high-intensity interval training and feasible modalities such as resistance training offer numerous benefits for firefighters. Also, modifying and supplementing the diet and can be advantageous for health and body composition in the fire service. Firefighters have various schedules, making it difficult for planned exercise and eating while on shift. The practical training and nutritional aspects discussed in this review can be implemented on-shift to improve the overall health and performance in firefighters.

10.
Ann Plast Surg ; 93(1): 89-93, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38885167

RESUMEN

INTRODUCTION: Reconstruction following pilonidal cyst resection must balance risk of recurrence, healing time, and resumption of functional routine. Propeller flaps provide a reliable and effective reconstructive option. This study highlights our experience with propeller flap reconstruction following pilonidal cyst resection and demonstrates the efficacy of same-day discharge. METHODS: A single-institution retrospective chart review was performed for propeller flap reconstructions completed from March 2018 to July 2022. Patient demographics, pilonidal cyst details, operative details, and postoperative outcomes were collected. Primary outcomes included flap survival, flap complications, and pilonidal disease recurrence. RESULTS: Twenty-eight outpatient propeller flap reconstructions following pilonidal cyst resections were identified in 26 patients, with two patients receiving a second propeller flap due to recurrence. Most patients were male (n = 15, 57.7%) with a mean age at time of index operation of 25.5 ± 5.8 years and mean body mass index of 26.5 ± 4.1 kg/m2. Mean symptom duration prior to index surgery was 39.3 months. Mean skin defect size following resection was 28.3 ± 15.3 cm2, with a mean flap size of 44.7 ± 35.5 cm2. Flap survival was 100% (n = 28), with five flaps (17.9%) experiencing minor wound complications and one patient (3.8%) requiring return to the operating room. Mean time to functional improvement was 24.0 ± 22.8 days. Pilonidal disease recurrence occurred in three patients (11.5%). Mean follow-up was 4.1 ± 5.4 months. CONCLUSIONS: Propeller flaps provide a successful and reliable reconstructive option for pilonidal disease defects. Because patients in our cohort experienced favorable outcomes and functional improvement, we advocate for same-day discharge in order to reduce hospital and patient burden.


Asunto(s)
Seno Pilonidal , Procedimientos de Cirugía Plástica , Humanos , Seno Pilonidal/cirugía , Masculino , Estudios Retrospectivos , Adulto , Femenino , Procedimientos de Cirugía Plástica/métodos , Alta del Paciente , Colgajos Quirúrgicos , Procedimientos Quirúrgicos Ambulatorios/métodos , Adulto Joven
12.
Soft Matter ; 20(20): 4111-4126, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38726733

RESUMEN

Across a variety of spatial scales, from nanoscale biological systems to micron-scale colloidal systems, equilibrium self-assembly is entirely dictated by-and therefore limited by-the thermodynamic properties of the constituent materials. In contrast, nonequilibrium materials, such as self-propelled active matter, expand the possibilities for driving the assemblies that are inaccessible in equilibrium conditions. Recently, a number of works have suggested that active matter drives or accelerates self-organization, but the emergent interactions that arise between solutes immersed in actively driven environments are complex and poorly understood. Here, we analyze and resolve two crucial questions concerning actively driven self-assembly: (i) how, mechanistically, do active environments drive self-assembly of passive solutes? (ii) Under which conditions is this assembly robust? We employ the framework of odd hydrodynamics to theoretically explain numerical and experimental observations that chiral active matter, i.e., particles driven with a directional torque, produces robust and long-ranged assembly forces. Together, these developments constitute an important step towards a comprehensive theoretical framework for controlling self-assembly in nonequilibrium environments.

13.
bioRxiv ; 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38712226

RESUMEN

Walking animals must maintain stability in the presence of external perturbations, despite significant temporal delays in neural signaling and muscle actuation. Here, we develop a 3D kinematic model with a layered control architecture to investigate how sensorimotor delays constrain robustness of walking behavior in the fruit fly, Drosophila. Motivated by the anatomical architecture of insect locomotor control circuits, our model consists of three component layers: a neural network that generates realistic 3D joint kinematics for each leg, an optimal controller that executes the joint kinematics while accounting for delays, and an inter-leg coordinator. The model generates realistic simulated walking that matches real fly walking kinematics and sustains walking even when subjected to unexpected perturbations, generalizing beyond its training data. However, we found that the model's robustness to perturbations deteriorates when sensorimotor delay parameters exceed the physiological range. These results suggest that fly sensorimotor control circuits operate close to the temporal limit at which they can detect and respond to external perturbations. More broadly, we show how a modular, layered model architecture can be used to investigate physiological constraints on animal behavior.

14.
ACS Nano ; 18(23): 14791-14840, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38814908

RESUMEN

We explore the potential of nanocrystals (a term used equivalently to nanoparticles) as building blocks for nanomaterials, and the current advances and open challenges for fundamental science developments and applications. Nanocrystal assemblies are inherently multiscale, and the generation of revolutionary material properties requires a precise understanding of the relationship between structure and function, the former being determined by classical effects and the latter often by quantum effects. With an emphasis on theory and computation, we discuss challenges that hamper current assembly strategies and to what extent nanocrystal assemblies represent thermodynamic equilibrium or kinetically trapped metastable states. We also examine dynamic effects and optimization of assembly protocols. Finally, we discuss promising material functions and examples of their realization with nanocrystal assemblies.

15.
Int J Obstet Anesth ; 59: 104210, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38781778

RESUMEN

Women with pulmonary hypertension (PH) have increased mortality during pregnancy and the peripartum period. An increasing number of publications suggest improvements in maternal outcomes, so we conducted a systematic review focusing on disease severity and maternal survival. After screening 9097 potential studies from 1967 to 2021, we identified 66 relevant publications. Outcomes improved continuously over time and mortality fell from 11.6% in studies published before 2015 to 8.2% in studies published after 2015. Mortality was lower in patients with mild disease (0.8%) than in those with Eisenmenger syndrome (26.2%) or idiopathic pulmonary arterial hypertension (7.4-24.0%). One major drawback of the published studies is that they define severity using echocardiographic-estimated pulmonary artery pressures, without considering more contemporary parameters. This systematic review provides new insights for preconception counseling on pregnancy risks related to PH and suggests that PH classification and severity should be carefully considered in determining an individual's pregnancy-associated risk.


Asunto(s)
Hipertensión Pulmonar , Complicaciones Cardiovasculares del Embarazo , Resultado del Embarazo , Índice de Severidad de la Enfermedad , Femenino , Humanos , Embarazo , Hipertensión Pulmonar/complicaciones
16.
Trends Endocrinol Metab ; 35(2): 125-141, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38577754

RESUMEN

Intermittent short-term fasting (ISTF) and ketogenic diets (KDs) exert overlapping but not identical effects on cell metabolism, function, and resilience. Whereas health benefits of KD are largely mediated by the ketone bodies (KBs), ISTF engages additional adaptive physiological responses. KDs act mainly through inhibition of histone deacetylases (HDACs), reduction of oxidative stress, improvement of mitochondria efficiency, and control of inflammation. Mechanisms of action of ISTF include stimulation of autophagy, increased insulin and leptin sensitivity, activation of AMP-activated protein kinase (AMPK), inhibition of the mechanistic target of rapamycin (mTOR) pathway, bolstering mitochondrial resilience, and suppression of oxidative stress and inflammation. Frequent switching between ketogenic and nonketogenic states may optimize health by increasing stress resistance, while also enhancing cell plasticity and functionality.


Asunto(s)
Dieta Cetogénica , Humanos , Cuerpos Cetónicos/metabolismo , Ayuno , Estrés Oxidativo/fisiología , Inflamación
17.
Front Pediatr ; 12: 1378008, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38633325

RESUMEN

Introduction: Approximately 1.5 million neonatal deaths occur among premature and small (low birthweight or small-for gestational age) neonates annually, with a disproportionate amount of this mortality occurring in low- and middle-income countries (LMICs). Hypothermia, the inability of newborns to regulate their body temperature, is common among prematurely born and small babies, and often underlies high rates of mortality in this population. In high-resource settings, incubators and radiant warmers are the gold standard for hypothermia, but this equipment is often scarce in LMICs. Kangaroo Mother Care/Skin-to-skin care (KMC/STS) is an evidence-based intervention that has been targeted for scale-up among premature and small neonates. However, KMC/STS requires hours of daily contact between a neonate and an able adult caregiver, leaving little time for the caregiver to care for themselves. To address this, we created a novel self-warming biomedical device, NeoWarm, to augment KMC/STS. The present study aimed to validate the safety and efficacy of NeoWarm. Methods: Sixteen, 0-to-5-day-old piglets were used as an animal model due to similarities in their thermoregulatory capabilities, circulatory systems, and approximate skin composition to human neonates. The piglets were placed in an engineered cooling box to drop their core temperature below 36.5°C, the World Health Organizations definition of hypothermia for human neonates. The piglets were then warmed in NeoWarm (n = 6) or placed in the ambient 17.8°C ± 0.6°C lab environment (n = 5) as a control to assess the efficacy of NeoWarm in regulating their core body temperature. Results: All 6 piglets placed in NeoWarm recovered from hypothermia, while none of the 5 piglets in the ambient environment recovered. The piglets warmed in NeoWarm reached a significantly higher core body temperature (39.2°C ± 0.4°C, n = 6) than the piglets that were warmed in the ambient environment (37.9°C ± 0.4°C, n = 5) (p < 0.001). No piglet in the NeoWarm group suffered signs of burns or skin abrasions. Discussion: Our results in this pilot study indicate that NeoWarm can safely and effectively warm hypothermic piglets to a normal core body temperature and, with additional validation, shows promise for potential use among human premature and small neonates.

18.
APL Photonics ; 9(2)2024.
Artículo en Inglés | MEDLINE | ID: mdl-38681736

RESUMEN

Microresonator frequency combs and their design versatility have revolutionized research areas from data communication to exoplanet searches. While microcombs in the 1550 nm band are well documented, there is interest in using microcombs in other bands. Here, we demonstrate the formation and spectral control of normal-dispersion dark soliton microcombs at 1064 nm. We generate 200 GHz repetition rate microcombs by inducing a photonic bandgap of the microresonator mode for the pump laser with a photonic crystal. We perform the experiments with normal-dispersion microresonators made from Ta2O5 and explore unique soliton pulse shapes and operating behaviors. By adjusting the resonator dispersion through its nanostructured geometry, we demonstrate control over the spectral bandwidth of these combs, and we employ numerical modeling to understand their existence range. Our results highlight how photonic design enables microcomb spectra tailoring across wide wavelength ranges, offering potential in bioimaging, spectroscopy, and photonic-atomic quantum technologies.

20.
Arch Orthop Trauma Surg ; 144(5): 2057-2066, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38641682

RESUMEN

INTRODUCTION: The importance of identifying how patients choose their healthcare providers has grown with the prevalence of consumer-centric health insurance plans. There is currently a lack of studies exploring the factors associated with how patients select their hip and knee joint arthroplasty surgeons. The purpose of this study was to determine how patients find their arthroplasty providers and the relative importance of various arthroplasty surgeon characteristics. METHODS: An electronic mail survey was sent to 3522 patients who had visited our institution for an arthroplasty surgeon office visit between August 2022 and January 2023. The survey consisted of multiple-choice questions, which aimed to inquire about the patients' referral sources for their current arthroplasty surgeon. In addition, patients were requested to rate the significance of 22 surgeon-related factors, on a scale of 1 (Not Important At All) to 5 (Very Important), in choosing their arthroplasty surgeon. RESULTS: Of the 3522 patients that received the survey, 538 patients responded (15.3%). The most common referral sources were physician referral (50.2%), family/friend referral (27.7%), and self-guided research (24.5%). Of those that were referred by a physician, 54.4% of respondents were referred by another orthopaedic provider. Patients rated board certification (4.72 ± 0.65), in-network insurance status (4.66 ± 0.71), fellowship training (4.50 ± 0.81), bedside manner/personality (4.32 ± 0.86), and facility appearance (4.26 ± 0.81) as the five most important factors in picking an arthroplasty surgeon. Television (1.42 ± 0.83), print (1.50 ± 0.88), and online (1.58 ± 0.93) advertisements, along with social media presence (1.83 ± 1.08), and practice group size (2.97 ± 1.13) were rated as the five least important factors. CONCLUSION: Patients are most likely to select an arthroplasty surgeon based on referral from other physicians, namely orthopedic surgeons, in addition to board certification status, in-network insurance, and fellowship training. Overall, these findings highlight the importance of physician credentials and reputation within the orthopaedic community in order to attract and retain patients.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Artroplastia de Reemplazo de Rodilla , Cirujanos Ortopédicos , Humanos , Artroplastia de Reemplazo de Cadera/estadística & datos numéricos , Artroplastia de Reemplazo de Rodilla/estadística & datos numéricos , Masculino , Femenino , Persona de Mediana Edad , Cirujanos Ortopédicos/estadística & datos numéricos , Anciano , Encuestas y Cuestionarios , Derivación y Consulta/estadística & datos numéricos , Adulto
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