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1.
Sci Rep ; 14(1): 14025, 2024 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890425

RESUMO

Regulatory T cells (Tregs) are a type of lymphocyte that is key to maintaining immunological self-tolerance, with great potential for therapeutic applications. A long-standing challenge in the study of Tregs is that the only way they can be unambiguously identified is by using invasive intracellular markers. Practically, the purification of live Tregs is often compromised by other cell types since only surrogate surface markers can be used. We present here a non-invasive method based on Raman spectroscopy that can detect live unaltered Tregs by coupling optical detection with machine learning implemented with regularized logistic regression. We demonstrate the validity of this approach first on murine cells expressing a surface Foxp3 reporter, and then on peripheral blood human T cells. By including methods to account for sample purity, we could generate reliable models that can identify Tregs with an accuracy higher than 80%, which is already comparable with typical sorting purities achievable with standard methods that use proxy surface markers. We could also demonstrate that it is possible to reliably detect Tregs in fully independent donors that are not part of the model training, a key milestone for practical applications.


Assuntos
Fatores de Transcrição Forkhead , Análise Espectral Raman , Linfócitos T Reguladores , Linfócitos T Reguladores/imunologia , Análise Espectral Raman/métodos , Humanos , Animais , Camundongos , Fatores de Transcrição Forkhead/metabolismo , Aprendizado de Máquina
2.
BMJ Open ; 14(6): e085125, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38830746

RESUMO

INTRODUCTION: Pain and disability after meniscectomy can be a substantial lifelong problem. There are few treatment options, especially for young people. Non-surgical management (rehabilitation) is an option but increasingly surgeons are performing meniscal allograft transplants (MATs) for these individuals. However, this is still an uncommon procedure, and availability and usage of MAT vary widely both in the UK and internationally. It is not known which treatment option is the most effective and cost-effective. METHODS AND ANALYSIS: The Meniscal Transplant surgery or Optimised Rehabilitation trial is an international, multicentre, randomised controlled trial. The aim is to compare the clinical and cost effectiveness of MAT versus an optimised package of individualised, progressive, rehabilitation that we have called personalised knee therapy (PKT).Participants will be recruited from sites across the UK, Australia, Canada and Belgium. The planned 144 participants provide at least 90% power to detect a 10-point difference in the Knee injury and Osteoarthritis Outcome Score (KOOS4) at 24-months post randomisation (primary outcome). A prospectively planned economic evaluation will be conducted from a healthcare system and personal social services perspective. Secondary outcome data including health utility, occupational status, sports participation, mental well-being, further treatment, and adverse events will be collected at 3, 6, 12, 18, and 24 months. Analysis will be on an intention-to-treat basis and reported in-line with the Consolidated Standards of Reporting Trials statement. ETHICS AND DISSEMINATION: The trial was approved by the London-Bloomsbury Research Ethics Committee on 19 August 2022 (22/LO/0327) and Northern Sydney Local Health District Human Research Ethics Committee, NSW, Australia on the 13 March 2023 (2022/ETH01890).Trial results will be disseminated via peer-reviewed publications, presentations at international conferences, in lay summaries and using social media as appropriate.This protocol adheres to the recommended Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) checklist. TRIAL REGISTRATION NUMBER: ISRCTN87336549.


Assuntos
Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Análise Custo-Benefício , Estudos Multicêntricos como Assunto , Meniscectomia , Meniscos Tibiais/cirurgia , Meniscos Tibiais/transplante , Lesões do Menisco Tibial/cirurgia , Lesões do Menisco Tibial/terapia , Lesões do Menisco Tibial/reabilitação
3.
J Food Prot ; 87(7): 100287, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38697482

RESUMO

Given its presence in a wide spectrum of soils relevant to food process hygiene, the biological metabolite adenosine triphosphate (ATP) is used as a target for surface hygiene assessments in food processing facilities. Yet, ample evidence demonstrates that ATP is depleted into adenosine di- (ADP) and monophosphate (AMP) homologs resulting in a loss of sensitivity for ATP-based hygiene assays. Yet, there are few studies that denote the degree of these shifts under routine processing conditions such as those encountered during various meat processing steps that may likely alter redox potential and adenosine profiles (e.g., tissue/cellular disruption, application of reducing additives, fermentation, or thermal treatment steps). In this study, meat samples were collected from homogenized beef tissue treated with nonmeat ingredients (sodium chloride, sodium nitrite, sodium erythorbate, natural smoke condensate, and sodium acid pyrophosphate) during manufacture at predetermined steps, and from retail meat products purchased from local markets. Concentrations of ATP, ADP, AMP, and AXP (sum concentration of all homologs) in a lab setting and in situ meat processing venues were determined and compared. Greater differences in AXP were seen during manufacture, where ADP generally comprised ∼90% as a mole fraction of AXP across all treatments, with the exception of the final cook step where AMP predominated. ATP concentrations averaged 2 log values lower than ADP and AMP. Adenosine profiles in retail samples followed similar trends with minimal ATP concentrations with ADP predominant in uncooked samples and AMP predominant in cooked samples. Resultingly, meat processing steps during product manufacture will alter AXP-reliant test sensitivities which should be considered when such technologies are utilized for hygiene verification in meat processing.


Assuntos
Trifosfato de Adenosina , Manipulação de Alimentos , Trifosfato de Adenosina/metabolismo , Animais , Carne/análise , Difosfato de Adenosina/metabolismo , Monofosfato de Adenosina , Contaminação de Alimentos/análise , Bovinos , Humanos , Produtos da Carne/análise
4.
J Public Health (Oxf) ; 46(2): e279-e293, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38426578

RESUMO

BACKGROUND: Non-pharmaceutical interventions (NPIs) were crucial in the response to the COVID-19 pandemic, although uncertainties about their effectiveness remain. This work aimed to better understand the evidence generated during the pandemic on the effectiveness of NPIs implemented in the UK. METHODS: We conducted a rapid mapping review (search date: 1 March 2023) to identify primary studies reporting on the effectiveness of NPIs to reduce COVID-19 transmission. Included studies were displayed in an interactive evidence gap map. RESULTS: After removal of duplicates, 11 752 records were screened. Of these, 151 were included, including 100 modelling studies but only 2 randomized controlled trials and 10 longitudinal observational studies.Most studies reported on NPIs to identify and isolate those who are or may become infectious, and on NPIs to reduce the number of contacts. There was an evidence gap for hand and respiratory hygiene, ventilation and cleaning. CONCLUSIONS: Our findings show that despite the large number of studies published, there is still a lack of robust evaluations of the NPIs implemented in the UK. There is a need to build evaluation into the design and implementation of public health interventions and policies from the start of any future pandemic or other public health emergency.


Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/prevenção & controle , COVID-19/transmissão , COVID-19/epidemiologia , Humanos , Reino Unido/epidemiologia , Pandemias/prevenção & controle , Controle de Doenças Transmissíveis/métodos , Lacunas de Evidências
5.
J Biomech ; 166: 111990, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38383232

RESUMO

Nucleus replacement devices (NRDs) have potential to treat degenerated or herniated intervertebral discs (IVDs). However, IVD height loss is a post-treatment complication. IVD height recovery involves the nucleus pulposus (NP), but the mechanism of this in response to physiological loads is not fully elucidated. This study aimed to characterise the non-linear recovery behaviour of the IVD in intact, post-nuclectomy, and post-NRD treatment states, under physiological loading. 36 bovine IVDs (12 intact, 12 post-nuclectomy, 12 post-treatment) underwent creep-recovery protocols simulating Sitting, Walking or Running, followed by 12 h of recovery. A rheological model decoupled the fluid-independent (elastic, fast) and fluid-dependent (slow) recovery phases. In post-nuclectomy and post-treatment groups, nuclectomy efficiency (ratio of NP removed to remaining NP) was quantified following post-test sectioning. Relative to intact, post-nuclectomy recovery significantly decreased in Sitting (-0.3 ± 0.4 mm, p < 0.05) and Walking (-0.6 ± 0.3 mm, p < 0.001) coupled with significant decreases to the slow response (p < 0.05). Post-nuclectomy, the fast and slow responses negatively correlated with nuclectomy efficiency (p < 0.05). In all protocols, the post-treatment group performed significantly worse in recovery (-0.5 ± 0.3 mm, p < 0.01) and the slow response (p < 0.05). Results suggest the NP mainly facilitates slow-phase recovery, linearly dependent on the amount of NP present. Failure of this NRD to recover is attributed to poor fluid imbibition. Additionally, unconfined NRD performance cannot be extrapolated to the in vitro response. This knowledge informs NRD design criteria to provide high osmotic pressure, and encourages testing standards to incorporate long-term recovery protocols.


Assuntos
Degeneração do Disco Intervertebral , Deslocamento do Disco Intervertebral , Disco Intervertebral , Núcleo Pulposo , Animais , Bovinos , Núcleo Pulposo/fisiologia , Degeneração do Disco Intervertebral/cirurgia , Disco Intervertebral/cirurgia , Disco Intervertebral/fisiologia , Deslocamento do Disco Intervertebral/cirurgia , Fenômenos Biomecânicos
7.
Public Health ; 226: 39-52, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38000113

RESUMO

OBJECTIVE: Alcohol consumption, smoking, and excess weight independently increase the risk of morbidity/mortality. Less is known about how they interact. This research aims to quantify the independent and joint associations of these exposures across health outcomes and identify whether these associations are synergistic. STUDY DESIGN: The protocol for this systematic review and meta-analysis was pre-registered (PROSPERO CRD42021231443). METHODS: Medline and Embase were searched between 1 January 2010 and 9 February 2022. Eligible peer-reviewed observational studies had to include adult participants from Organisation for Co-Operation and Development countries and report independent and joint associations between at least two eligible exposures (alcohol, smoking, and excess weight) and an ICD-10 outcome (or equivalent). For all estimates, we calculated the synergy index (SI) to identify whether joint associations were synergistic. Meta-analyses were conducted for outcomes with sufficiently homogenous data. RESULTS: The search returned 26,290 studies, of which 98 were included. Based on 138,130 participants, the combined effect (SI) of alcohol and smoking on head and neck cancer death/disease was 3.78 times greater than the additive effect of each exposure (95% confidence interval [CI] = 2.61, 5.48). Based on 2,603,939 participants, the combined effect of alcohol and excess weight on liver disease/death was 1.55 times greater than the additive effect of each exposure (95% CI = 1.33, 1.82). CONCLUSION: Synergistic associations suggest the true population-level risk may be underestimated. In the absence of bias, individuals with multiple risks would experience a greater absolute risk reduction from an intervention that targets a single exposure than individuals with a single risk.


Assuntos
Consumo de Bebidas Alcoólicas , Fumar , Adulto , Humanos , Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/epidemiologia , Fatores de Risco , Fumar/efeitos adversos , Fumar/epidemiologia , Sobrepeso
8.
Science ; 382(6676): 1287-1291, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38096420

RESUMO

The hydrogen-rich outer layers of massive stars can be removed by interactions with a binary companion. Theoretical models predict that this stripping produces a population of hot helium stars of ~2 to 8 solar masses (M☉), however, only one such system has been identified thus far. We used ultraviolet photometry to identify potential stripped helium stars then investigated 25 of them using optical spectroscopy. We identified stars with high temperatures (~60,000 to 100,000 kelvin), high surface gravities, and hydrogen-depleted surfaces; 16 stars also showed binary motion. These properties match expectations for stars with initial masses of 8 to 25 M☉ that were stripped by binary interaction. Their masses fall in the gap between subdwarf helium stars and Wolf-Rayet stars. We propose that these stars could be progenitors of stripped-envelope supernovae.

10.
Nanotechnology ; 35(9)2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38016446

RESUMO

This study describes computer simulations of carbonization and graphite formation, including the effects of hydrogen, nitrogen, oxygen, and sulfur. We introduce a novel technique to simulate carbonization, 'Simulation of Thermal Emission of Atoms and Molecules (STEAM)', designed to elucidate volatile outgassing and density variations in the intermediate material during carbonization. The investigation analyzes the functional groups that endure through high-temperature carbonization and examines the graphitization processes in carbon-rich materials containing non-carbon impurity elements. The physical, vibrational, and electronic attributes of impure amorphous graphite are analyzed, and the impact of nitrogen on electronic conduction is investigated.

11.
Int J Pediatr Otorhinolaryngol ; 171: 111657, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37441989

RESUMO

INTRODUCTION: We previously reported that endoscopic repair of a Type 1 Laryngeal Cleft (LC1) or Deep Interarytenoid Groove (DIG) improves swallowing function postoperatively. However, caregivers often ask about the timeline to resolution of the need for thickening. This study re-examines this cohort to answer this important caregiver-centered question. METHODS: We reassessed a 3-year retrospective, single-center dataset of children with dysphagia found to have a LC-1 or DIG on endoscopic exam. The primary outcome was rate of complete resolution of dysphagia at 2, 6, and 12 months after endoscopic intervention. A sub-group analysis was made based on severity of dysphagia prior to intervention and by type of endoscopic repair. RESULTS: Thirty-nine patients with mean age 1.35 years that had a LC-1 or DIG met criteria for inclusion. Rate of complete dysphagia resolution increased over time. Those with mild dysphagia (flow-reducing nipple and/or IDDSI consistency 1 or 2) had brisker resolution than those with moderate dysphagia (IDDSI consistency 3 or 4) at 2 months (67% vs 5%, p < 0.01) and at 6 months (80% vs 18%, p < 0.01) after endoscopic repair. There was no difference in dysphagia resolution between patients grouped by type of endoscopic repair. CONCLUSION: Addressing an interarytenoid defect in patients will not result in immediate, complete dysphagia resolution in most patients. However, patients that only require a flow-reducing nipple and/or thickening to an IDDSI consistency 1 or 2 have brisker resolution of the need for thickening than those that require an IDSSI consistency 3 or 4 prior to intervention. These results inform pre-operative discussions of the timeline to resolution based upon severity of dysphagia and help manage caregiver expectations.


Assuntos
Transtornos de Deglutição , Endoscopia , Laringe , Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Estudos Retrospectivos , Transtornos de Deglutição/diagnóstico por imagem , Transtornos de Deglutição/etiologia , Laringe/diagnóstico por imagem , Laringe/cirurgia , Deglutição , Resultado do Tratamento
12.
NPJ Microgravity ; 9(1): 59, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37524737

RESUMO

Space exploration objectives will soon move from low Earth orbit to distant destinations like Moon and Mars. The present work provides an up-to-date roadmap that identifies critical research gaps related to human behavior and performance in altered gravity and space. The roadmap summarizes (1) key neurobehavioral challenges associated with spaceflight, (2) the need to consider sex as a biological variable, (3) the use of integrative omics technologies to elucidate mechanisms underlying changes in the brain and behavior, and (4) the importance of understanding the neural representation of gravity throughout the brain and its multisensory processing. We then highlight the need for a variety of target-specific countermeasures, and a personalized administration schedule as two critical strategies for mitigating potentially adverse effects of spaceflight on the central nervous system and performance. We conclude with a summary of key priorities for the roadmaps of current and future space programs and stress the importance of new collaborative strategies across agencies and researchers for fostering an integrative cross- and transdisciplinary approach from cells, molecules to neural circuits and cognitive performance. Finally, we highlight that space research in neurocognitive science goes beyond monitoring and mitigating risks in astronauts but could also have significant benefits for the population on Earth.

13.
Osteoarthritis Cartilage ; 31(7): 944-953, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36924920

RESUMO

INTRODUCTION: Co-design is a consumer-driven approach that facilitates consumer participation in creating meaningful solutions to complex problems. Poor uptake of core management strategies for osteoarthritis suggests there is a missing link in translation between research and practice. We partnered with osteoarthritis consumers as 'co-researchers' to identify translational research solutions to improve uptake of core management strategies that are grounded in lived experiences. OBJECTIVE: To transparently describe a theory-driven, generative co-design approach using an integrated conceptual framework to collaborate with consumers at the equal partnership level. DESIGN: We used co-design workshops with a non-hierarchical participatory framework. Three workshops with six co-researchers [2 female, mean age 68.7 (9.8) years, 3-30 years symptom duration] were conducted using activities to encourage creative thinking, promote deep reflection on personal/societal beliefs and minimise sensitivities around sharing personal beliefs (e.g., establishing a safe space, prompting questions, perspective-taking, counter-stereotypical exemplars). RESULTS: All six co-researchers actively participated in the workshops. Achievement of an equal collaborative partnership was evidenced by co-researchers challenging a project proposed by the research team and making alternative recommendations that have been implemented in prospective decision-making - representing a complete change in research focus driven by consumer input. A key suggested solution was to develop a scalable knowledge translation intervention that targets misconceptions about osteoarthritis and its management at the societal-level. CONCLUSIONS: Through an innovative co-design approach in partnership with co-researchers, we identified meaningful areas on which to focus translational research for osteoarthritis. Discordance between existing research priorities and novel solutions proposed by co-researchers highlights the value of co-design.


Assuntos
Criatividade , Pesquisa Translacional Biomédica , Humanos , Feminino , Idoso , Ciência Translacional Biomédica , Participação da Comunidade
14.
Sci Rep ; 13(1): 2163, 2023 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-36750714

RESUMO

Presented here is a magnetic hydrogel particle enabled workflow for capturing and concentrating SARS-CoV-2 from diagnostic remnant swab samples that significantly improves sequencing results using the Oxford Nanopore Technologies MinION sequencing platform. Our approach utilizes a novel affinity-based magnetic hydrogel particle, circumventing low input sample volumes and allowing for both rapid manual and automated high throughput workflows that are compatible with Nanopore sequencing. This approach enhances standard RNA extraction protocols, providing up to 40 × improvements in viral mapped reads, and improves sequencing coverage by 20-80% from lower titer diagnostic remnant samples. Furthermore, we demonstrate that this approach works for contrived influenza virus and respiratory syncytial virus samples, suggesting that it can be used to identify and improve sequencing results of multiple viruses in VTM samples. These methods can be performed manually or on a KingFisher automation platform.


Assuntos
COVID-19 , Sequenciamento por Nanoporos , Humanos , SARS-CoV-2 , Sequenciamento por Nanoporos/métodos , Hidrogéis , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Fenômenos Magnéticos
15.
J Synchrotron Radiat ; 30(Pt 1): 76-83, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36601928

RESUMO

This report presents testing of a prototype cantilevered liquid-nitrogen-cooled silicon mirror. This mirror was designed to be the first mirror for the new soft X-ray beamlines to be built as part of the Advanced Light Source Upgrade. Test activities focused on fracture, heat transfer, modal response and distortion, and indicated that the mirror functions as intended.

17.
Anaesthesia ; 78(2): 180-187, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36336462

RESUMO

Pharmacokinetic modelling suggests that sugammadex may interact with endogenous progesterone and reduce levels by 34% in patients taking hormonal contraception. Due to this potential interaction that may be equivalent to missing one dose of an oral contraceptive pill, both the manufacturer and professional anaesthesia organisations recommend counselling patients to use additional non-hormonal contraception after administration of sugammadex. We performed a prospective observational study examining the changes in serum oestrogen and progesterone concentrations in premenopausal adult women undergoing an operative procedure. Sixty participants who were on hormonal contraception received sugammadex. Two additional control groups were recruited, consisting of 30 participants who were not on hormonal contraception and did not receive sugammadex, and 32 who were not on hormonal contraception and did receive sugammadex. Three blood samples were taken: before sugammadex; 15 min post-sugammadex; and 240 min post-sugammadex or end of operating theatre time. Median oestrogen levels decreased from baseline by around 40% at 240 min in all three groups (p ≤ 0.001). Progesterone levels rose significantly at 15 min (p = 0.002) in patients on contraception then decreased non-significantly to 20% below baseline at 240 min. The decrease in oestrogen and the rise in progesterone could both act to minimise the risk of ovulation and thus protect contraception in this population. We found no evidence of a change in hormone levels that might threaten contraceptive efficacy in women on hormonal contraception receiving sugammadex.


Assuntos
Anticoncepção , Progesterona , Adulto , Humanos , Feminino , Sugammadex/farmacologia , Anticoncepção/métodos , Estrogênios , Estudos Prospectivos
18.
Doc Ophthalmol ; 145(2): 163-174, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35947237

RESUMO

PURPOSE: The purpose of this paper is to present a case study illustrating the importance of electrophysiological investigation in the diagnosis and serial monitoring of isolated congenital nystagmus. RESULTS: Serial electophysiological monitoring was undertaken in the male proband over a 9-year period commencing with initial assessment at 12 weeks of age: Skin electroretinograms (sERGs) were initially absent but subsequently revealed low-amplitude responses, electronegative morphologies and notched flicker responses suggestive of incomplete congenital stationary night blindness (CSNB2), but with an absent dark-adapted rod-specific response, while flash visual evoked potentials (fVEPs) demonstrated persistent crossed asymmetry, typical of albinoid misrouting of the optic nerves. Molecular investigation confirmed a novel hemizygous frame shift mutation in the CACNA1F gene, considered to be pathogenic and causative of X-linked CSNB2; additionally, a novel heterozygous missense variation in one copy of the RIMS1 gene was identified, pathogenic mutations of which underpin late-onset autosomal dominant cone-rod dystrophy (type 7). Segregation studies confirmed maternal inheritance of both mutations in the clinically asymptomatic mother in whom depressed rod-specific responses were confirmed on sERG. The child's visual acuity has remained stable as have the sERGs which have been verified by recordings using scleral electrodes. CONCLUSIONS: The importance of recording ERGs as part of evaluating infants who present with nystagmus, even with a normal fundus appearance, is supported. Further, sERGs were able to distinguish an apparent variant of CSNB2 and could give consistent results over many years. FVEP results add to the evidence that albinoid misrouting of the optic nerves may occur in cases of CSNB2. ERGs and fVEPs can provide valuable information in discriminating the relative diagnostic importance of multiple genetic abnormalities.


Assuntos
Doenças Genéticas Ligadas ao Cromossomo X , Cegueira Noturna , Canais de Cálcio Tipo L/genética , Criança , Eletrorretinografia , Potenciais Evocados Visuais , Oftalmopatias Hereditárias , Mutação da Fase de Leitura , Doenças Genéticas Ligadas ao Cromossomo X/genética , Humanos , Lactente , Masculino , Mutação , Miopia , Cegueira Noturna/diagnóstico , Cegueira Noturna/genética
20.
Plant Biol (Stuttg) ; 24(5): 766-779, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35398958

RESUMO

Low-temperature thermal acclimation may require adjustments to N and water use to sustain photosynthesis because of slow enzyme functioning and high water viscosity. However, understanding of photosynthetic acclimation to temperatures below 11 °C is limited. We acclimated Populus balsamifera to 6 °C and 10 °C (6A and 10A, respectively) and provided the trees with either high or low N fertilizer. We measured net CO2 assimilation (Anet ), stomatal conductance (gs ), maximum rates of Rubisco carboxylation (Vcmax ), electron transport (Jmax ) and dark respiration (Rd ) at leaf temperatures of 2, 6, 10, 14 and 18 °C, along with leaf N concentrations. The 10A trees had higher Anet than the 6A trees at warmer leaf temperatures, which was correlated with higher gs in the 10A trees. The instantaneous temperature responses of Vcmax , Jmax and Rd were similar for trees from both acclimation temperatures. While soil N availability increased leaf N concentrations, this had no effect on acclimation of photosynthesis or respiration. Our results indicate that acclimation below 11 °C occurred primarily through changes in stomatal conductance, not photosynthetic biochemistry, and was unaffected by short-term N supply. Thermal acclimation of stomatal conductance should therefore be a priority for future carbon cycle model development.


Assuntos
Populus , Aclimatação/fisiologia , Dióxido de Carbono , Nitrogênio , Fotossíntese/fisiologia , Folhas de Planta/fisiologia , Populus/fisiologia , Temperatura , Árvores/fisiologia , Água
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