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1.
Cell ; 185(8): 1287-1289, 2022 04 14.
Artículo en Inglés | MEDLINE | ID: mdl-35385686

RESUMEN

From mRNA vaccines to community interventions in global child health, the 2022 Canada Gairdner awards demonstrate the importance of fundamental science and its translation into improved human health and well-being.


Asunto(s)
Distinciones y Premios , Investigación Biomédica , Canadá , Niño , Familia , Salud Global , Humanos
2.
Cell ; 184(8): 1949-1952, 2021 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-33831376

RESUMEN

Interdisciplinary work has played a key role in Dr. Elizabeth Eisenhauer's wide-ranging research contributions and leadership in cancer clinical trials, drug delivery, treatment standards, and research and prevention strategy. Cell editor Emma Yee talked with Dr. Eisenhauer, recipient of the 2021 Canada Gairdner Wightman Award, to learn more about the factors that influenced her work in cancer care and the lessons she learned along the way. This conversation is presented below, edited for clarity and length. Note the National Cancer Institute of Canada Clinical Trials Group (NCIC CTG) was renamed the Canadian Cancer Trials Group (CCTG) in 2016. In this interview, the two are used interchangeably.


Asunto(s)
Neoplasias/patología , Antineoplásicos/uso terapéutico , Distinciones y Premios , Investigación Biomédica , Canadá , Descubrimiento de Drogas , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo
3.
Cell ; 181(3): 503-506, 2020 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-32234522

RESUMEN

Pioneering research from Mina Bissell established the "Dynamic-Reciprocity" view of biology in which there is a bidirectional interaction between cells and their microenvironment. Her revolutionary work showed that extracellular matrix signaling and microenvironment impact gene expression, taking cancer research beyond genetics. For these contributions, she is the recipient of the 2020 Canada Gairdner International Award. Growing up in a well-educated family in Iran, Mina liked to ask many "why" questions. She spoke with Cell editor Miao-Chih Tsai about how she tackles scientific questions and life challenges. Excerpts from this conversation are presented below, and the full conversation is available with the article online.


Asunto(s)
Comunicación/historia , Distinciones y Premios , Canadá , Matriz Extracelular/fisiología , Femenino , Historia del Siglo XX , Historia del Siglo XXI , Humanos
4.
Cell ; 181(3): 495-497, 2020 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-32234519

RESUMEN

This year's Canada Gairdner International Prize is shared by Rolf Kemler and Masatoshi Takeichi for the discovery of the cadherin family of Ca2+-dependent cell-cell adhesion proteins, which play essential roles in animal evolution, tissue development, and homeostasis, and are disrupted in human cancers.


Asunto(s)
Cadherinas/metabolismo , Cadherinas/fisiología , Comunicación Celular/fisiología , Animales , Distinciones y Premios , Fenómenos Biofísicos , Canadá , Adhesión Celular/fisiología , Historia del Siglo XX , Historia del Siglo XXI , Homeostasis/fisiología , Humanos , Masculino
5.
Cell ; 181(3): 492-494, 2020 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-32234524

RESUMEN

The 2020 Canada Gairdner International Award has been awarded to Elaine Fuchs for her discovery of the role of adult skin stem cells in homeostasis, wound repair, inflammation, and cancer. These insights have established a foundation for basic knowledge on how adult stem cells form, maintain, and repair tissues and have provided the groundwork for additional exploration and discovery of pathways in other stem cell systems.


Asunto(s)
Células Madre Adultas/metabolismo , Células Madre Adultas/fisiología , Piel/metabolismo , Animales , Distinciones y Premios , Canadá , Células Epidérmicas/metabolismo , Femenino , Historia del Siglo XX , Historia del Siglo XXI , Homeostasis/fisiología , Humanos , Neoplasias/metabolismo , Cicatrización de Heridas/fisiología
8.
Nature ; 633(8031): 835-839, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39198654

RESUMEN

The 2023 Canadian forest fires have been extreme in scale and intensity with more than seven times the average annual area burned compared to the previous four decades1. Here, we quantify the carbon emissions from these fires from May to September 2023 on the basis of inverse modelling of satellite carbon monoxide observations. We find that the magnitude of the carbon emissions is 647 TgC (570-727 TgC), comparable to the annual fossil fuel emissions of large nations, with only India, China and the USA releasing more carbon per year2. We find that widespread hot-dry weather was a principal driver of fire spread, with 2023 being the warmest and driest year since at least 19803. Although temperatures were extreme relative to the historical record, climate projections indicate that these temperatures are likely to be typical during the 2050s, even under a moderate climate mitigation scenario (shared socioeconomic pathway, SSP 2-4.5)4. Such conditions are likely to drive increased fire activity and suppress carbon uptake by Canadian forests, adding to concerns about the long-term durability of these forests as a carbon sink5-8.


Asunto(s)
Carbono , Bosques , Incendios Forestales , Canadá , Carbono/análisis , Carbono/química , Dióxido de Carbono/análisis , Monóxido de Carbono/análisis , Secuestro de Carbono , Modelos Climáticos , Sequías , Combustibles Fósiles/efectos adversos , Historia del Siglo XXI , Calor , Factores Socioeconómicos , Incendios Forestales/historia , Incendios Forestales/estadística & datos numéricos
9.
Cell ; 159(6): 1239-42, 2014 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-25480286

RESUMEN

The 2014 Nobel Prize in Physiology or Medicine, awarded to John O'Keefe, May-Britt Moser, and Edvard I. Moser, recognizes the first deep-brain insights into a cognitive function. Their insights established a new view for how the brain represents spatial location.


Asunto(s)
Hipocampo/fisiología , Neurociencias/historia , Premio Nobel , Fisiología/historia , Animales , Canadá , Inglaterra , Historia del Siglo XX , Humanos , Noruega , Navegación Espacial
10.
Nature ; 601(7893): 388-391, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34671168

RESUMEN

Transatlantic exploration took place centuries before the crossing of Columbus. Physical evidence for early European presence in the Americas can be found in Newfoundland, Canada1,2. However, it has thus far not been possible to determine when this activity took place3-5. Here we provide evidence that the Vikings were present in Newfoundland in AD 1021. We overcome the imprecision of previous age estimates by making use of the cosmic-ray-induced upsurge in atmospheric radiocarbon concentrations in AD 993 (ref. 6). Our new date lays down a marker for European cognisance of the Americas, and represents the first known point at which humans encircled the globe. It also provides a definitive tie point for future research into the initial consequences of transatlantic activity, such as the transference of knowledge, and the potential exchange of genetic information, biota and pathologies7,8.


Asunto(s)
Emigrantes e Inmigrantes , Américas , Canadá , Radiación Cósmica , Humanos , Terranova y Labrador , Paleontología
11.
Nature ; 608(7923): 563-568, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35859171

RESUMEN

A fundamental gap in the study of the origin of limbed vertebrates lies in understanding the morphological and functional diversity of their closest relatives. Whereas analyses of the elpistostegalians Panderichthys rhombolepis, Tiktaalik roseae and Elpistostege watsoni have revealed a sequence of changes in locomotor, feeding and respiratory structures during the transition1-9, an isolated bone, a putative humerus, has controversially hinted at a wider range in form and function than now recognized10-14. Here we report the discovery of a new elpistostegalian from the Late Devonian period of the Canadian Arctic that shows surprising disparity in the group. The specimen includes partial upper and lower jaws, pharyngeal elements, a pectoral fin and scalation. This new genus is phylogenetically proximate to T. roseae and E. watsoni but evinces notable differences from both taxa and, indeed, other described tetrapodomorphs. Lacking processes, joint orientations and muscle scars indicative of appendage-based support on a hard substrate13, its pectoral fin shows specializations for swimming that are unlike those known from other sarcopterygians. This unexpected morphological and functional diversity represents a previously hidden ecological expansion, a secondary return to open water, near the origin of limbed vertebrates.


Asunto(s)
Evolución Biológica , Peces , Fósiles , Aletas de Animales/anatomía & histología , Escamas de Animales/anatomía & histología , Animales , Regiones Árticas , Canadá , Peces/anatomía & histología , Peces/clasificación , Historia Antigua , Mandíbula/anatomía & histología , Faringe/anatomía & histología , Filogenia , Natación
12.
Annu Rev Cell Dev Biol ; 30: 1-21, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25288111

RESUMEN

In this perspective I look back on the twists and turns that influenced the direction of my scientific career over the past 40 years. From my early ambition to be a chemist to my training in Philadelphia and Bethesda as a molecular biologist, I benefited enormously from generous and valuable mentoring. In my independent career in Philadelphia and Princeton, I was motivated by a keen interest in the changes in gene expression that direct the development of the mammalian embryo and inspired by the creativity and energy of my students, fellows, and research staff. After twelve years as President of Princeton University, I have happily returned to the faculty of the Department of Molecular Biology.


Asunto(s)
Biología Molecular/historia , Universidades/historia , Secuencia de Aminoácidos , Animales , Canadá , Paseo de Cromosoma , Desarrollo Embrionario/genética , Proteínas del Ojo/genética , Proteínas del Ojo/historia , Regulación del Desarrollo de la Expresión Génica , Impresión Genómica , Historia del Siglo XX , Historia del Siglo XXI , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/historia , Humanos , Ratones , Datos de Secuencia Molecular , National Institutes of Health (U.S.) , New Jersey , Factor de Transcripción PAX6 , Factores de Transcripción Paired Box/genética , Factores de Transcripción Paired Box/historia , Empalme del ARN , ARN Largo no Codificante/genética , ARN Largo no Codificante/historia , Proteínas Represoras/genética , Proteínas Represoras/historia , Estados Unidos , alfa-Fetoproteínas/genética , alfa-Fetoproteínas/historia , Globinas beta/genética , Globinas beta/historia
13.
N Engl J Med ; 390(9): 819-829, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38416430

RESUMEN

BACKGROUND: Retrospective data suggest that the incidence of parametrial infiltration is low in patients with early-stage low-risk cervical cancer, which raises questions regarding the need for radical hysterectomy in these patients. However, data from large, randomized trials comparing outcomes of radical and simple hysterectomy are lacking. METHODS: We conducted a multicenter, randomized, noninferiority trial comparing radical hysterectomy with simple hysterectomy including lymph-node assessment in patients with low-risk cervical cancer (lesions of ≤2 cm with limited stromal invasion). The primary outcome was cancer recurrence in the pelvic area (pelvic recurrence) at 3 years. The prespecified noninferiority margin for the between-group difference in pelvic recurrence at 3 years was 4 percentage points. RESULTS: Among 700 patients who underwent randomization (350 in each group), the majority had tumors that were stage IB1 according to the 2009 International Federation of Gynecology and Obstetrics (FIGO) criteria (91.7%), that had squamous-cell histologic features (61.7%), and that were grade 1 or 2 (59.3%). With a median follow-up time of 4.5 years, the incidence of pelvic recurrence at 3 years was 2.17% in the radical hysterectomy group and 2.52% in the simple hysterectomy group (an absolute difference of 0.35 percentage points; 90% confidence interval, -1.62 to 2.32). Results were similar in a per-protocol analysis. The incidence of urinary incontinence was lower in the simple hysterectomy group than in the radical hysterectomy group within 4 weeks after surgery (2.4% vs. 5.5%; P = 0.048) and beyond 4 weeks (4.7% vs. 11.0%; P = 0.003). The incidence of urinary retention in the simple hysterectomy group was also lower than that in the radical hysterectomy group within 4 weeks after surgery (0.6% vs. 11.0%; P<0.001) and beyond 4 weeks (0.6% vs. 9.9%; P<0.001). CONCLUSIONS: In patients with low-risk cervical cancer, simple hysterectomy was not inferior to radical hysterectomy with respect to the 3-year incidence of pelvic recurrence and was associated with a lower risk of urinary incontinence or retention. (Funded by the Canadian Cancer Society and others; ClinicalTrials.gov number, NCT01658930.).


Asunto(s)
Carcinoma de Células Escamosas , Histerectomía , Neoplasias del Cuello Uterino , Femenino , Humanos , Canadá , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/cirugía , Histerectomía/efectos adversos , Histerectomía/métodos , Ganglios Linfáticos/patología , Recurrencia Local de Neoplasia/epidemiología , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Incontinencia Urinaria/etiología , Retención Urinaria/etiología , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/cirugía
14.
N Engl J Med ; 390(22): 2061-2073, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38767248

RESUMEN

BACKGROUND: Many persons with chronic obstructive pulmonary disease (COPD) or asthma have not received a diagnosis, so their respiratory symptoms remain largely untreated. METHODS: We used a case-finding method to identify adults in the community with respiratory symptoms without diagnosed lung disease. Participants who were found to have undiagnosed COPD or asthma on spirometry were enrolled in a multicenter, randomized, controlled trial to determine whether early diagnosis and treatment reduces health care utilization for respiratory illness and improves health outcomes. Participants were assigned to receive the intervention (evaluation by a pulmonologist and an asthma-COPD educator who were instructed to initiate guideline-based care) or usual care by their primary care practitioner. The primary outcome was the annualized rate of participant-initiated health care utilization for respiratory illness. Secondary outcomes included changes from baseline to 1 year in disease-specific quality of life, as assessed with the St. George Respiratory Questionnaire (SGRQ; scores range from 0 to 100, with lower scores indicating better health status); symptom burden, as assessed with the COPD Assessment Test (CAT; scores range from 0 to 40, with lower scores indicating better health status); and forced expiratory volume in 1 second (FEV1). RESULTS: Of 38,353 persons interviewed, 595 were found to have undiagnosed COPD or asthma and 508 underwent randomization: 253 were assigned to the intervention group and 255 to the usual-care group. The annualized rate of a primary-outcome event was lower in the intervention group than in the usual-care group (0.53 vs. 1.12 events per person-year; incidence rate ratio, 0.48; 95% confidence interval [CI], 0.36 to 0.63; P<0.001). At 12 months, the SGRQ score was lower than the baseline score by 10.2 points in the intervention group and by 6.8 points in the usual-care group (difference, -3.5 points; 95% CI, -6.0 to -0.9), and the CAT score was lower than the baseline score by 3.8 points and 2.6 points, respectively (difference, -1.3 points; 95% CI, -2.4 to -0.1). The FEV1 increased by 119 ml in the intervention group and by 22 ml in the usual-care group (difference, 94 ml; 95% CI, 50 to 138). The incidence of adverse events was similar in the trial groups. CONCLUSIONS: In this trial in which a strategy was used to identify adults in the community with undiagnosed asthma or COPD, those who received pulmonologist-directed treatment had less subsequent health care utilization for respiratory illness than those who received usual care. (Funded by Canadian Institutes of Health Research; UCAP ClinicalTrials.gov number, NCT03148210.).


Asunto(s)
Asma , Diagnóstico Precoz , Enfermedad Pulmonar Obstructiva Crónica , Calidad de Vida , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Asma/diagnóstico , Asma/terapia , Volumen Espiratorio Forzado , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/terapia , Espirometría , Canadá/epidemiología , Utilización de Instalaciones y Servicios/estadística & datos numéricos , Aceptación de la Atención de Salud
15.
N Engl J Med ; 390(2): 107-117, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-37952132

RESUMEN

BACKGROUND: Subclinical atrial fibrillation is short-lasting and asymptomatic and can usually be detected only by long-term continuous monitoring with pacemakers or defibrillators. Subclinical atrial fibrillation is associated with an increased risk of stroke by a factor of 2.5; however, treatment with oral anticoagulation is of uncertain benefit. METHODS: We conducted a trial involving patients with subclinical atrial fibrillation lasting 6 minutes to 24 hours. Patients were randomly assigned in a double-blind, double-dummy design to receive apixaban at a dose of 5 mg twice daily (2.5 mg twice daily when indicated) or aspirin at a dose of 81 mg daily. The trial medication was discontinued and anticoagulation started if subclinical atrial fibrillation lasting more than 24 hours or clinical atrial fibrillation developed. The primary efficacy outcome, stroke or systemic embolism, was assessed in the intention-to-treat population (all the patients who had undergone randomization); the primary safety outcome, major bleeding, was assessed in the on-treatment population (all the patients who had undergone randomization and received at least one dose of the assigned trial drug, with follow-up censored 5 days after permanent discontinuation of trial medication for any reason). RESULTS: We included 4012 patients with a mean (±SD) age of 76.8±7.6 years and a mean CHA2DS2-VASc score of 3.9±1.1 (scores range from 0 to 9, with higher scores indicating a higher risk of stroke); 36.1% of the patients were women. After a mean follow-up of 3.5±1.8 years, stroke or systemic embolism occurred in 55 patients in the apixaban group (0.78% per patient-year) and in 86 patients in the aspirin group (1.24% per patient-year) (hazard ratio, 0.63; 95% confidence interval [CI], 0.45 to 0.88; P = 0.007). In the on-treatment population, the rate of major bleeding was 1.71% per patient-year in the apixaban group and 0.94% per patient-year in the aspirin group (hazard ratio, 1.80; 95% CI, 1.26 to 2.57; P = 0.001). Fatal bleeding occurred in 5 patients in the apixaban group and 8 patients in the aspirin group. CONCLUSIONS: Among patients with subclinical atrial fibrillation, apixaban resulted in a lower risk of stroke or systemic embolism than aspirin but a higher risk of major bleeding. (Funded by the Canadian Institutes of Health Research and others; ARTESIA ClinicalTrials.gov number, NCT01938248.).


Asunto(s)
Anticoagulantes , Aspirina , Fibrilación Atrial , Embolia , Accidente Cerebrovascular , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Anticoagulantes/efectos adversos , Anticoagulantes/uso terapéutico , Aspirina/efectos adversos , Aspirina/uso terapéutico , Fibrilación Atrial/complicaciones , Fibrilación Atrial/diagnóstico , Canadá , Embolia/etiología , Embolia/prevención & control , Hemorragia/inducido químicamente , Piridonas/efectos adversos , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/prevención & control , Resultado del Tratamiento , Inhibidores del Factor Xa/efectos adversos , Inhibidores del Factor Xa/uso terapéutico , Método Doble Ciego
16.
N Engl J Med ; 390(5): 409-420, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38294973

RESUMEN

BACKGROUND: Studies evaluating surgical-site infection have had conflicting results with respect to the use of alcohol solutions containing iodine povacrylex or chlorhexidine gluconate as skin antisepsis before surgery to repair a fractured limb (i.e., an extremity fracture). METHODS: In a cluster-randomized, crossover trial at 25 hospitals in the United States and Canada, we randomly assigned hospitals to use a solution of 0.7% iodine povacrylex in 74% isopropyl alcohol (iodine group) or 2% chlorhexidine gluconate in 70% isopropyl alcohol (chlorhexidine group) as preoperative antisepsis for surgical procedures to repair extremity fractures. Every 2 months, the hospitals alternated interventions. Separate populations of patients with either open or closed fractures were enrolled and included in the analysis. The primary outcome was surgical-site infection, which included superficial incisional infection within 30 days or deep incisional or organ-space infection within 90 days. The secondary outcome was unplanned reoperation for fracture-healing complications. RESULTS: A total of 6785 patients with a closed fracture and 1700 patients with an open fracture were included in the trial. In the closed-fracture population, surgical-site infection occurred in 77 patients (2.4%) in the iodine group and in 108 patients (3.3%) in the chlorhexidine group (odds ratio, 0.74; 95% confidence interval [CI], 0.55 to 1.00; P = 0.049). In the open-fracture population, surgical-site infection occurred in 54 patients (6.5%) in the iodine group and in 60 patients (7.3%) in the chlorhexidine group (odd ratio, 0.86; 95% CI, 0.58 to 1.27; P = 0.45). The frequencies of unplanned reoperation, 1-year outcomes, and serious adverse events were similar in the two groups. CONCLUSIONS: Among patients with closed extremity fractures, skin antisepsis with iodine povacrylex in alcohol resulted in fewer surgical-site infections than antisepsis with chlorhexidine gluconate in alcohol. In patients with open fractures, the results were similar in the two groups. (Funded by the Patient-Centered Outcomes Research Institute and the Canadian Institutes of Health Research; PREPARE ClinicalTrials.gov number, NCT03523962.).


Asunto(s)
Antiinfecciosos Locales , Clorhexidina , Fijación de Fractura , Fracturas Óseas , Yodo , Infección de la Herida Quirúrgica , Humanos , 2-Propanol/administración & dosificación , 2-Propanol/efectos adversos , 2-Propanol/uso terapéutico , Antiinfecciosos Locales/administración & dosificación , Antiinfecciosos Locales/efectos adversos , Antiinfecciosos Locales/uso terapéutico , Antisepsia/métodos , Canadá , Clorhexidina/administración & dosificación , Clorhexidina/efectos adversos , Clorhexidina/uso terapéutico , Etanol , Extremidades/lesiones , Extremidades/microbiología , Extremidades/cirugía , Yodo/administración & dosificación , Yodo/efectos adversos , Yodo/uso terapéutico , Cuidados Preoperatorios/efectos adversos , Cuidados Preoperatorios/métodos , Piel/microbiología , Infección de la Herida Quirúrgica/etiología , Infección de la Herida Quirúrgica/prevención & control , Fracturas Óseas/cirugía , Estudios Cruzados , Estados Unidos
17.
Cell ; 149(7): 1417-9, 2012 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-22726427

RESUMEN

Abandoning an earlier pretense that research misconduct is too rare to matter, the scientific community is trying to figure out how to minimize and police it. Could broadening the definition be the key?


Asunto(s)
Mala Conducta Científica , Canadá , Internacionalidad , Internet , Investigación/economía , Investigación/legislación & jurisprudencia , Mala Conducta Científica/ética , Mala Conducta Científica/legislación & jurisprudencia , Mala Conducta Científica/tendencias , Estados Unidos , United States Office of Research Integrity
18.
Proc Natl Acad Sci U S A ; 121(44): e2322269121, 2024 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-39432792

RESUMEN

Climate warming enables easier access and operation in the Arctic, fostering industrial and urban development. However, there is no comprehensive pan-Arctic overview of industrial and urban development, which is crucial for the planning of sustainable development of the region. In this study, we utilize satellite-derived artificial light at night (ALAN) data to quantify the hotspots and the development of light-emitting human activity across the Arctic from 1992 to 2013. We find that out of 16.4 million km2 analyzed a total area of 839,710 km2 (5.14%) is lit by human activity with an annual increase of 4.8%. The European Arctic and the oil and gas extraction regions in Russia and Alaska are hotspots of ALAN with up to a third of the land area lit, while the Canadian Arctic remains dark to a large extent. On average, only 15% of lit area in the Arctic contains human settlement, indicating that artificial light is largely attributable to industrial human activity. With this study, we provide a standardized approach to spatially assess human industrial activity across the Arctic, independent from economic data. Our results provide a crucial baseline for sustainable development and conservation planning across the highly vulnerable Arctic region.


Asunto(s)
Desarrollo Industrial , Regiones Árticas , Humanos , Federación de Rusia , Luz , Alaska , Iluminación , Canadá , Cambio Climático , Actividades Humanas
19.
Proc Natl Acad Sci U S A ; 121(31): e2321245121, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39008689

RESUMEN

Beef production has been identified as a significant source of anthropogenic greenhouse gas (GHG) emissions in the agricultural sector. United States and Canada account for about a quarter of the world's beef supply. To compare the GHG emission contributions of alternative beef production systems, we conducted a meta-analysis of 32 studies that were conducted between 2001 and 2023. Results indicated that GHG emissions from beef production in North America varied almost fourfold from 10.2 to 37.6 with an average of 21.4 kg CO2e/kg carcass weight (CW). Studies that considered soil C sequestration (C-seq) reported the highest mitigation potential in GHG emissions (80%), followed by growth enhancement technology (16%), diet modification (6%), and grazing management improvement (7%). Our study highlights the implications of using carbon intensity per economic activity (i.e., GHG emissions per monetary unit), compared to the more common metric of intensity on per weight of product basis (GHG emissions per kg CW) for comparisons across differentiated beef cattle products. While a positive association was found between the proportion of lifespan on grassland and the conventional weight-based indicator, grass-finished beef was found to have lower carbon intensity per economic activity than feedlot-finished beef. Our study emphasizes the need to incorporate land use and management effects and soil C-seq as fundamental aspects of beef GHG emissions and mitigation assessments.


Asunto(s)
Gases de Efecto Invernadero , Carne Roja , Animales , Bovinos , Gases de Efecto Invernadero/análisis , Carne Roja/economía , Canadá , Crianza de Animales Domésticos/métodos , Crianza de Animales Domésticos/economía , Estados Unidos , Agricultura/economía , Agricultura/métodos , Efecto Invernadero , Cambio Climático
20.
Proc Natl Acad Sci U S A ; 121(32): e2317686121, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39074272

RESUMEN

Indigenous communities in the North American Arctic are characterized by mixed economies that feature hunting, fishing, gathering, and trapping activities-and associated sharing practices-alongside the formal wage economy. The region is also undergoing rapid social, economic, and climate changes, including, in Canada, carbon taxation, which is impacting the cost of fuel used in local food harvesting. Because of the importance of local foods to nutrition, health, and well-being in Arctic Indigenous communities, there is an urgent need to better understand the sensitivity of Arctic food systems to social, economic, and climate changes and to develop plans for mitigating potential adverse effects. Here, we develop a Bayesian model to calculate the substitution value and carbon emissions of market replacements for local food harvests in the Inuvialuit Settlement Region, Canada. Our estimates suggest that under plausible scenarios, replacing locally harvested foods with imported market substitutes would cost over 3.1 million Canadian dollars per year and emit over 1,000 tons of CO2-equivalent emissions per year, regardless of the shipping scenario. In contrast, we estimate that gasoline inputs to harvesting cost approximately $295,000 and result in 315 to 497 tons of emissions. These results indicate that climate change policies that fail to account for local food production may undermine emissions targets and adversely impact food security and health in Arctic Indigenous communities, who already experience a high cost of living and high rates of food insecurity.


Asunto(s)
Cambio Climático , Abastecimiento de Alimentos , Canadá , Abastecimiento de Alimentos/economía , Humanos , Cambio Climático/economía , Regiones Árticas , Teorema de Bayes , Carbono/metabolismo , Pueblos Indígenas , Alimentos/economía , Dióxido de Carbono/análisis , Dióxido de Carbono/metabolismo
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