Aviation emissions that are dispersed into the Earth's atmosphere affect the climate and air pollution, with significant spatiotemporal variation owing to heterogeneous aircraft activity. In this ...paper, we use historical flight trajectories derived from Automatic Dependent Surveillance–Broadcast (ADS-B) telemetry and reanalysis weather data for 2019–2021 to develop the Global Aviation emissions Inventory based on ADS-B (GAIA). In 2019, 40.2 million flights collectively travelled 61 billion kilometres using 283 Tg of fuel, leading to CO2, NOX and non-volatile particulate matter (nvPM) mass and number emissions of 893 Tg, 4.49 Tg, 21.4 Gg and 2.8 × 1026 respectively. Global responses to COVID-19 led to reductions in the annual flight distance flown and CO2 and NOX emissions in 2020 (−43 %, −48 % and −50 % respectively relative to 2019) and 2021 (−31 %, −41 % and −43 % respectively), with significant regional variability. Short-haul flights with durations < 3 h accounted for 83 % of all flights but only for 35 % of the 2019 CO2 emissions, while long-haul flights with durations > 6 h (5 % of all flights) were responsible for 43 % of CO2 and 49 % of NOX emissions. Globally, the actual flight trajectories flown are, on average, ∼ 5 % greater than the great circle path between the origin and destination airports, but this varies by region and flight distance. An evaluation of 8705 unique flights between London and Singapore showed large variabilities in the flight trajectory profile, fuel consumption and emission indices. GAIA captures the spatiotemporal distribution of aviation activity and emissions and is provided for use in future studies to evaluate the negative externalities arising from global aviation.
Around 5 % of anthropogenic radiative forcing (RF) is
attributed to aviation CO2 and non-CO2 impacts. This paper
quantifies aviation emissions and contrail climate forcing in the North
Atlantic, one ...of the world's busiest air traffic corridors, over 5 years.
Between 2016 and 2019, growth in CO2 (+3.13 % yr−1) and
nitrogen oxide emissions (+4.5 % yr−1) outpaced increases in flight
distance (+3.05 % yr−1). Over the same period, the annual mean contrail
cirrus net RF (204–280 mW m−2) showed significant inter-annual
variability caused by variations in meteorology. Responses to COVID-19
caused significant reductions in flight distance travelled (−66 %),
CO2 emissions (−71 %) and the contrail net RF (−66 %) compared with
the prior 1-year period. Around 12 % of all flights in this region cause
80 % of the annual contrail energy forcing, and the factors associated
with strongly warming/cooling contrails include seasonal changes in
meteorology and radiation, time of day, background cloud fields, and
engine-specific non-volatile particulate matter (nvPM) emissions. Strongly
warming contrails in this region are generally formed in wintertime, close
to the tropopause, between 15:00 and 04:00 UTC, and above low-level clouds.
The most strongly cooling contrails occur in the spring, in the upper
troposphere, between 06:00 and 15:00 UTC, and without lower-level clouds.
Uncertainty in the contrail cirrus net RF (216–238 mW m−2) arising
from meteorology in 2019 is smaller than the inter-annual variability. The
contrail RF estimates are most sensitive to the humidity fields, followed by
nvPM emissions and aircraft mass assumptions. This longitudinal evaluation
of aviation contrail impacts contributes a quantified understanding of
inter-annual variability and informs strategies for contrail mitigation.
The current best-estimate of the global annual mean radiative forcing (RF) attributable to contrail cirrus is thought to be 3 times larger than the RF from aviation's cumulative CO2 emissions. Here, ...we simulate the global contrail RF for 2019–2021 using reanalysis weather data and improved engine emission estimates along actual flight trajectories derived from Automatic Dependent Surveillance–Broadcast telemetry. Our 2019 global annual mean contrail net RF (62.1 mW m−2) is 44 % lower than current best estimates for 2018 (111 33, 189 mW m−2, 95 % confidence interval). Regionally, the contrail net RF is largest over Europe (876 mW m−2) and the USA (414 mW m−2), while the RF values over East Asia (64 mW m−2) and China (62 mW m−2) are close to the global average, because fewer flights in these regions form persistent contrails resulting from lower cruise altitudes and limited ice supersaturated regions in the subtropics due to the Hadley Circulation. Globally, COVID-19 reduced the flight distance flown and contrail net RF in 2020 (−43 % and −56 %, respectively, relative to 2019) and 2021 (−31 % and −49 %, respectively) with significant regional variations. Around 14 % of all flights in 2019 formed a contrail with a net warming effect, yet only 2 % of all flights caused 80 % of the annual contrail energy forcing. The spatiotemporal patterns of the most strongly warming and cooling contrail segments can be attributed to flight scheduling, engine particle number emissions, tropopause height, and background radiation fields. Our contrail RF estimates are most sensitive to corrections applied to the global humidity fields, followed by assumptions on the engine particle number emissions, and are least sensitive to radiative heating effects on the contrail plume and contrail–contrail overlapping. Using this sensitivity analysis, we estimate that the 2019 global contrail net RF could range between 34.8 and 74.8 mW m−2.
To quantify the incidence of anemia and red blood cell (RBC) transfusion practice in critically ill patients and to examine the relationship of anemia and RBC transfusion to clinical outcomes.
...Prospective, multiple center, observational cohort study of intensive care unit (ICU) patients in the United States. Enrollment period was from August 2000 to April 2001. Patients were enrolled within 48 hrs of ICU admission. Patient follow-up was for 30 days, hospital discharge, or death, whichever occurred first.
A total of 284 ICUs (medical, surgical, or medical-surgical) in 213 hospitals participated in the study.
A total of 4,892 patients were enrolled in the study.
The mean hemoglobin level at baseline was 11.0 +/- 2.4 g/dL. Hemoglobin level decreased throughout the duration of the study. Overall, 44% of patients received one or more RBC units while in the ICU (mean, 4.6 +/- 4.9 units). The mean pretransfusion hemoglobin was 8.6 +/- 1.7 g/dL. The mean time to first ICU transfusion was 2.3 +/- 3.7 days. More RBC transfusions were given in study week 1; however, in subsequent weeks, subjects received one to two RBC units per week while in the ICU. The number of RBC transfusions a patient received during the study was independently associated with longer ICU and hospital lengths of stay and an increase in mortality. Patients who received transfusions also had more total complications and were more likely to experience a complication. Baseline hemoglobin was related to the number of RBC transfusions, but it was not an independent predictor of length of stay or mortality. However, a nadir hemoglobin level of <9 g/dL was a predictor of increased mortality and length of stay.
Anemia is common in the critically ill and results in a large number of RBC transfusions. Transfusion practice has changed little during the past decade. The number of RBC units transfused is an independent predictor of worse clinical outcome.
Objectives
To evaluate the incidence of spinal fractures and their outcomes in the elderly who fall from low‐levels in a suburban county.
Design
Retrospective county‐wide trauma registry review from ...2004 to 2013.
Setting
Suburban county with regionalized trauma care consisting of 11 hospitals.
Participants
Adult trauma patients aged ≥65 years who were admitted after falling from <3 feet.
Measurements
Demographic characteristics, comorbidities, and outcomes.
Results
Spinal fractures occurred in 18% of 4,202 older adult patients admitted following trauma over this 10‐year time period, in the following distribution: 43% cervical spine, 5.7% thoracic, 4.9% lumbar spine, 36% sacrococcygeal, and 9.6% multiple spinal regions. As compared to non‐spinal fracture patients, more spinal fracture patients went to acute/subacute rehabilitation (47% vs 34%, P < .001) and fewer were discharged home (21% vs 35%, P < .001). In‐hospital mortality rate in spinal and non‐spinal fracture patients was similar (8.5% vs 9.3%, P = .5).
Conclusion
Low‐level falls often resulted in a spinal fracture at a variety of levels. Vigilance in evaluation of the entire spine in this population is suggested.
The purpose of this study was to test the null hypothesis that there is no association between perioperative laboratory markers (serum albumin and hemoglobin A1c HbA1c) and incidence of surgical site ...infection (SSI) after soft tissue upper extremity surgery.
We analyzed patient-level data from a large, insurance-based database containing supplemental laboratory results. We identified patients undergoing soft tissue upper extremity surgery (defined as carpal tunnel release, trigger finger release, wrist ganglion excision, cubital tunnel release, Dupuytren partial fasciectomy, or first dorsal compartment release) with serum albumin or HbA1c measurements within 90 days of surgery. We stratified patients into cohorts based on serum albumin concentration (<3.5 g/dL) and HbA1c (≥7%) thresholds. The primary outcome was incidence of SSI within 30 days following surgery. We constructed multivariable logistic regression models to adjust for patient demographics and baseline comorbidities using the Elixhauser comorbidity index.
Patients with hypoalbuminemia experienced an SSI incidence of 3.5% compared to 0.9% in patients with normal serum albumin. In multivariable analysis, the odds ratio of SSI with hypoalbuminemia was 3.32 (95% CI, 2.32–4.65). Patients with HbA1c ≥ 7% experienced an SSI incidence of 1.1% compared to 0.7% in patients with HbA1c < 7%. Multivariable analysis revealed odds ratios for SSI of 1.47 (95% CI, 1.02–2.11) in patients with HbA1c ≥ 7% compared to those with HbA1c < 7%.
Hypoalbuminemia and elevated HbA1c (in patients with diabetes) are risk factors for SSI within 30 days following soft tissue upper extremity surgery. Preoperative measurement of these laboratory markers may be a useful tool for risk stratification and identification of high-risk patients for nutritional or glycemic optimization.
Prognostic II.
As the burden of surgical care and the associated outreach trips to low- and middle-income countries increases, it is important to collect postoperative data to assess and improve the quality, ...safety, and efficacy of the care provided. In this pilot study, we aimed to evaluate the feasibility of short message service (SMS)-based mobile phone follow up to obtain patient-reported outcome measures after hand surgery during a surgical outreach trip to Vietnam.
Patients undergoing surgery during a week-long outreach trip to Hospital 175 in Ho Chi Minh City, Vietnam, who owned a mobile phone, were included in this study. Eight eligible patients elected to participate and were sent an SMS-based, Health Insurance Portability and Accountability Act-compliant text message with a link to a contextualized shortened Disabilities of the Arm, Shoulder and Hand questionnaire at 1 day, 1 week, 2 weeks, 4 weeks, and 12 weeks after the surgery. The patient characteristics and instrument completion rates were reported.
The 8 patients had a mean age of 45.4 years and lived at a mean distance of 72.7 km from the hospital. Seven (87.5%), 7 (87.5%), 8 (100%), 6 (75%), and 8 (100%) patients completed the follow-up questionnaires at 1 day, 1 week, 2 weeks, 4 weeks, and 12 weeks after the surgery, respectively.
This pilot study demonstrates that the collection of patient-reported outcome measures after hand surgery outreach trips to low- and middle-income countries via SMS-based messaging is feasible for up to 12 weeks after the surgery.
Short message service-based messaging can be used to obtain postoperative outcome measures for up to 12 weeks after surgical outreach trips to low- and middle-income countries. This technology can be scaled and contextualized based on location to ensure that patient care during outreach trips is safe and effective.
Cocoa production in humid forest landscapes has been one of the main cash providers of West and Central African economies. Along with the liberalization of the perennial tree sector, there are ...increased fluctuations of cocoa income. At the same time, the demand and interest for timber production and non-wood forest products have also been increasing. With the continuous disappearance of natural forests, the production of these commodities is being shifted into cocoa agroforests and plantations. In view of helping research and development institutions in promoting sustainable tree crop systems, this paper attempts, for the main cocoa producing countries of West Africa (Cameroon, Nigeria, Ghana and Côte d’Ivoire), to: (1) document the temporal evolution of the market demand for forests and non-wood forest products both at the local and international levels; (2) explore the set of tree species that can be produced in cocoa agroforests of WCA to satisfy this demand. Deforestation resulting partly from the expansion of perennial orchards and slash and burn agriculture is: (i) leading to a shortage of suitable forest land necessary to stabilize or increase national cocoa production and (ii) increasing the gap between the demand and availability/supply of non-wood forest products (NWFP) and timber by reducing the main source of these products—the forest. Demand of these products is increasing with the growth of urban and peri-urban centers. At the same time, perennial agroforestry systems such as cocoa agroforest are increasingly perceived as assets for Payment for Environmental Services (PES) such as carbon storage and biodiversity conservation, because of the potential of the resources that they can generate. These demands of products and payment for ecosystem services that can be provided by sustainable cocoa agroforestry systems depends upon the appropriate combination of cocoa, timber and non-timber forest trees on the same land. Such demands is still to be properly exploited in the region. Cocoa agroforests in West Africa are characterized by fewer species than those of Central Africa. The level of market access influences the types of species that are managed inside cocoa agroforests. Among the species potentially associable with cocoa, those demanded by the local, regional and international markets are not necessarily the ones that are more frequent in the cocoa fields. The gradual reduction of natural forest, from which timber and non-timber products are gathered, aroused the need to integrate the growing of such species in cocoa agroforestry systems.
Cocoa agroforests are growing in importance with a view to meeting farmers’ livelihood goals as well as ecological services. Following the recognition of cocoa agroforests as being useful for ...biodiversity conservation and farmers’ livelihoods, there is a growing discourse on the fact that they may also be useful in climate change mitigation and biodiversity conservation. Several companies have expressed their willingness to be “deforestation” certified within the next two decades. In West and Central Africa, cocoa is part of the endeavour to contribute to the REDD+ mechanism. Besides producing cocoa beans, the additional expectations from cocoa agroforests (timber, NWFP, biodiversity conservation, carbon storage, etc…) depend on the trees associated with the cocoa plants. The manner in which associated trees are mixed in the system impacts on the cocoa plants and plants associated with cocoa trees within the agroforestry system thus impact on the products and services produced by these farming systems. Studies are being undertaken to identify the exact composition of these associated trees but very few deal with the manner in which these trees are structurally distributed—vertically and horizontally—within the cocoa agroforest. Understanding the way in which cocoa and non-cocoa trees are distributed within the system would be useful with a view to improving the farm system, thus meeting the needs of several stakeholders. The present study reviews the structure of cocoa orchards and agroforests in West and Central Africa (Cameroon, Nigeria, Ghana and Cote d’Ivoire) with a view to improving the products and services of cocoa landscapes. This review is centred around: (i) density of cocoa, (ii) density of associated plants, (iii) basal area or associated plants, (iv) stratification and space between components, and (v) the life cycle of cocoa plantation components.
Densities of cocoa and associated plants in the field are not always those advised by extension services. The cocoa varieties play an important role in type and intensity of shade of the cocoa farms. In the context of multiple expectations placed on cocoa plantations, the unproductive cocoa trees in the farmer fields can be substituted by more vigorous ones or replaced by useful associated plants (Timber and NWFP). With the growing desire to reproduce some key attributes of local forests while responding to other economic and social needs associated with cocoa farms, the neighbouring/previous forest climax and its related basal area can be considered as a reasonable aim, when managing the cocoa agroforest. The life cycle of each of the plant components needs to be optimized in these spatial–temporal intensification considerations. In the prospect of vertical intensification, there is a need to give more attention to understorey management and the number of strata of the agroforest. In the context of sustainable management, a well-structured cocoa agroforest system needs to take landscape, local, national and global socio-economic and political issues into consideration.
Abstract Background Do Not Resuscitate (DNR) orders have been associated with poor outcomes in surgical patients. There is limited literature on admitted trauma patients with advanced directives ...indicating DNR status before admission (preadmission DNR PADNR). Methods A retrospective review of the trauma registry of a suburban county was carried out for admitted trauma patients with age ≥41 years, who were admitted between 2008 and 2013. Results Of 7,937 admitted patients, 327 had a preadmission advanced directive indicating DNR. PADNR patients were significantly older (87 vs 69 years), with more frequent comorbidities, and were more often admitted after a fall (94.2% vs 65.8%). PADNR patients had a higher Injury Severity Score (14 vs 11). They also had significantly increased rates of pneumonia, sepsis, myocardial infarction, and death (33.6% vs 5.9%). On multivariate logistic regression, the presence of a preadmission advanced directive indicating DNR status was independently associated with a 5.2-fold increased odds of mortality. Conclusion An advanced directive indicating DNR is associated with adverse outcomes following trauma.
