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1.
Agron Sustain Dev ; 43(5): 60, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37637434

RESUMEN

Agriculture faces potentially competing societal demands to produce food, fiber and fuel while reducing negative environmental impacts and delivering regulating, supporting and cultural ecosystem services. This necessitates a new generation of long-term agricultural field experiments designed to study the behavior of contrasting cropping systems in terms of multiple outcomes. We document the principles and practices of a new long-term experiment of this type at Rothamsted, established at two contrasting sites in 2017 and 2018, and report initial yield data at the crop and system level. The objective of the Large-Scale Rotation Experiment was to establish gradients of system properties and outcomes to improve our fundamental understanding of UK cropping systems. It is composed of four management factors-phased rotations, cultivation (conventional vs reduced tillage), nutrition (additional organic amendment vs standard mineral fertilization) and crop protection (conventional vs smart crop protection). These factors were combined in a balanced design resulting in 24 emergent cropping systems at each site and can be analyzed at the level of the system or component management factors. We observed interactions between management factors and with the environment on crop yields, justifying the systems level, multi-site approach. Reduced tillage resulted in lower wheat yields but the effect varied with rotation, previous-crop and site. Organic amendments significantly increased spring barley yield by 8% on average though the effect again varied with site. The plowed cropping systems tended to produce higher caloric yield overall than systems under reduced tillage. Additional response variables are being monitored to study synergies and trade-offs with outcomes other than yield at the cropping system level. The experiment has been established as a long-term resource for inter-disciplinary research. By documenting the design process, we aim to facilitate the adoption of similar approaches to system-scale agricultural experimentation to inform the transition to more sustainable cropping systems. Supplementary Information: The online version contains supplementary material available at 10.1007/s13593-023-00914-8.

2.
PLoS One ; 18(6): e0285478, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37310957

RESUMEN

Many publications lack sufficient background information (e.g. location) to be interpreted, replicated, or reused for synthesis. This impedes scientific progress and the application of science to practice. Reporting guidelines (e.g. checklists) improve reporting standards. They have been widely taken up in the medical sciences, but not in ecological and agricultural research. Here, we use a community-centred approach to develop a reporting checklist (AgroEcoList 1.0) through surveys and workshops with 23 experts and the wider agroecological community. To put AgroEcoList in context, we also assessed the agroecological community's perception of reporting standards in agroecology. A total of 345 researchers, reviewers, and editors, responded to our survey. Although only 32% of respondents had prior knowledge of reporting guidelines, 76% of those that had said guidelines improved reporting standards. Overall, respondents agreed on the need of AgroEcolist 1.0; only 24% of respondents had used reporting guidelines before, but 78% indicated they would use AgroEcoList 1.0. We updated AgroecoList 1.0 based on respondents' feedback and user-testing. AgroecoList 1.0 consists of 42 variables in seven groups: experimental/sampling set-up, study site, soil, livestock management, crop and grassland management, outputs, and finances. It is presented here, and is also available on github (https://github.com/AgroecoList/Agroecolist). AgroEcoList 1.0 can serve as a guide for authors, reviewers, and editors to improve reporting standards in agricultural ecology. Our community-centred approach is a replicable method that could be adapted to develop reporting checklists in other fields. Reporting guidelines such as AgroEcoList can improve reporting standards and therefore the application of research to practice, and we recommend that they are adopted more widely in agriculture and ecology.


Asunto(s)
Agricultura , Lista de Verificación , Animales , Suelo , Conocimiento , Ganado
3.
F1000Res ; 10: 324, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-36873457

RESUMEN

Artificial Intelligence (AI) is increasingly used within plant science, yet it is far from being routinely and effectively implemented in this domain. Particularly relevant to the development of novel food and agricultural technologies is the development of validated, meaningful and usable ways to integrate, compare and visualise large, multi-dimensional datasets from different sources and scientific approaches. After a brief summary of the reasons for the interest in data science and AI within plant science, the paper identifies and discusses eight key challenges in data management that must be addressed to further unlock the potential of AI in crop and agronomic research, and particularly the application of Machine Learning (AI) which holds much promise for this domain.

4.
New Phytol ; 227(1): 260-273, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32171029

RESUMEN

Enabling data reuse and knowledge discovery is increasingly critical in modern science, and requires an effort towards standardising data publication practices. This is particularly challenging in the plant phenotyping domain, due to its complexity and heterogeneity. We have produced the MIAPPE 1.1 release, which enhances the existing MIAPPE standard in coverage, to support perennial plants, in structure, through an explicit data model, and in clarity, through definitions and examples. We evaluated MIAPPE 1.1 by using it to express several heterogeneous phenotyping experiments in a range of different formats, to demonstrate its applicability and the interoperability between the various implementations. Furthermore, the extended coverage is demonstrated by the fact that one of the datasets could not have been described under MIAPPE 1.0. MIAPPE 1.1 marks a major step towards enabling plant phenotyping data reusability, thanks to its extended coverage, and especially the formalisation of its data model, which facilitates its implementation in different formats. Community feedback has been critical to this development, and will be a key part of ensuring adoption of the standard.


Asunto(s)
Fenómica , Plantas , Plantas/genética
5.
Health Technol Assess ; 24(10): 1-54, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32090730

RESUMEN

BACKGROUND: Randomised controlled trials demonstrating improved longevity are needed to justify high-dose vitamin D supplementation for older populations. OBJECTIVES: To demonstrate the feasibility of a large trial (n ≈ 20,000) of high-dose vitamin D in people aged 65-84 years through general practitioner (GP) practices, and to cluster randomise participating practices between open-label and double-blind randomisation to compare effects on recruitment, compliance and contamination. DESIGN: Twenty GP practices were randomised in matched pairs between open-label and double-blind allocation. Within each practice, patients were individually randomised to vitamin D or control (i.e. no treatment or placebo). Participants were invited to attend their GP practice to provide a blood sample and complete a lifestyle questionnaire at recruitment and again at 2 years. Randomisation by telephone followed receipt of a serum corrected calcium assay confirming eligibility (< 2.65 nmol/l). Treatment compliance was reported by quarterly follow-up forms sent and returned by e-mail or post (participant choice). GP visits and infections were abstracted from GP records. Hospital attendances, cancer diagnoses and deaths were ascertained by linkage to Hospital Episode Statistics and national registration through NHS Digital. SETTING: GP practices in England. PARTICIPANTS: Recruitment opened in October 2013 and closed in January 2015. A total of 1615 registered patients aged 65-84 years were randomised: 407 to vitamin D and 421 to no treatment in open practices; 395 to vitamin D and 392 to placebo in blind practices. INTERVENTIONS: There was a 24-month treatment period: 12 monthly doses (100,000 IU of vitamin D3 or placebo as 5 ml oily solution) were posted after randomisation and at 1 year (100,000 IU per month corresponds to 3300 IU per day). Reminders were sent monthly by e-mail, text message or post. MAIN OUTCOME MEASURES: Recruitment, compliance, contamination and change in circulating 25-hydroxyvitamin D [25(OH)D] from baseline to 2 years. RESULTS: Participation rates (randomised/invited) were 15.0% in open practices and 13.4% in double-blind practices (p = 0.7). The proportion still taking study medication at 2 years was 91.2% in open practices and 89.2% in double-blind practices (p = 0.4). The proportion of control participants taking > 400 IU vitamin D per day at 2 years was 5.0% in open practices and 4.8% in double-blind practices. Mean serum 25(OH)D concentration was 51.5 nmol/l [95% confidence interval (CI) 50.2 to 52.8 nmol/l] with 82.6% of participants < 75 nmol/l at baseline. At 2 years, this increased to 109.6 nmol/l (95% CI 107.1 to 112.1 nmol/l) with 12.0% < 75 nmol/l in those allocated to vitamin D and was unaltered at 51.8 nmol/l (95% CI 49.8 to 53.8 nmol/l) in those allocated to no vitamin D (no treatment or placebo). CONCLUSIONS: A trial could recruit 20,000 participants aged 65-84 years through 200 GP practices over 2 years. Approximately 80% would be expected to adhere to allocated treatment (vitamin D or placebo) for 5 years. The trial could be conducted entirely by e-mail in participants aged < 80 years, but some participants aged 80-84 years would require postal follow-up. Recruitment and treatment compliance would be similar and contamination (self-administration of vitamin D) would be minimal, whether control participants are randomised openly to no treatment with no contact during the trial or randomised double-blind to placebo with monthly reminders. TRIAL REGISTRATION: Current Controlled Trials ISRCTN46328341 and EudraCT database 2011-003699-34. FUNDING: This project was funded by the National Institute for Health Research Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 10. See the NIHR Journals Library website for further project information.


High-dose vitamin D may reduce the risk of many diseases, but without large randomised controlled trials the evidence will remain inconclusive. We therefore proposed the Vitamin D and Longevity (VIDAL) trial, with 20,000 older people randomised to either no vitamin D medication or vitamin D medication for 5 years. The VIDAL feasibility study was conducted to establish the procedures required for the main trial, including assessment of recruitment, compliance (taking study treatment as directed) and contamination (how many control participants started taking vitamin D). This was done in two sets of general practitioner (GP) practices: (1) 'open' practices, in which participants knew their treatment allocation (2 years of 100,000 IU vitamin D monthly or no treatment), and (2) 'double-blind' practices, in which participants and their GPs did not know whether they were taking vitamin D or placebo oil. We invited 11,376 men and women aged 65­84 years from 20 GP practices in England and 1615 (14%) took part. Ninety per cent of participants allocated to monthly oil took it for 2 years and few participants used vitamin supplements outside the trial, with no marked differences between open-label and double-blind arms. The best way to conduct the main trial will therefore depend on other considerations. A double-blind trial provides reliable evidence on effects where reporting could be influenced by you or your doctor knowing your treatment, which is important for many illnesses and any side effects of treatment. However, any long-term effects are likely to be considerably greater if treatment continues instead of stopping after 5 years when the main trial ends. An open trial is easier to conduct and, when it ends, those taking vitamin D can be offered a continuing supply so that the effect of lifelong treatment can be studied for major diseases and life expectancy, which are unlikely to be affected by individuals knowing whether or not they are taking vitamin D.


Asunto(s)
Suplementos Dietéticos , Médicos Generales , Mortalidad , Cooperación del Paciente , Vitamina D/administración & dosificación , Anciano , Anciano de 80 o más Años , Método Doble Ciego , Estudios de Factibilidad , Femenino , Humanos , Masculino , Encuestas y Cuestionarios , Reino Unido
6.
Sci Data ; 5: 180072, 2018 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-29762552

RESUMEN

The electronic Rothamsted Archive, e-RA (www.era.rothamsted.ac.uk) provides a permanent managed database to both securely store and disseminate data from Rothamsted Research's long-term field experiments (since 1843) and meteorological stations (since 1853). Both historical and contemporary data are made available via this online database which provides the scientific community with access to a unique continuous record of agricultural experiments and weather measured since the mid-19th century. Qualitative information, such as treatment and management practices, plans and soil information, accompanies the data and are made available on the e-RA website. e-RA was released externally to the wider scientific community in 2013 and this paper describes its development, content, curation and the access process for data users. Case studies illustrate the diverse applications of the data, including its original intended purposes and recent unforeseen applications. Usage monitoring demonstrates the data are of increasing interest. Future developments, including adopting FAIR data principles, are proposed as the resource is increasingly recognised as a unique archive of data relevant to sustainable agriculture, agroecology and the environment.

7.
Lancet Gastroenterol Hepatol ; 2(1): 23-31, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-28404010

RESUMEN

BACKGROUND: Barrett's oesophagus predisposes to adenocarcinoma. However, most patients with Barrett's oesophagus will not progress and endoscopic surveillance is invasive, expensive, and fraught by issues of sampling bias and the subjective assessment of dysplasia. We investigated whether a non-endoscopic device, the Cytosponge, could be coupled with clinical and molecular biomarkers to identify a group of patients with low risk of progression suitable for non-endoscopic follow-up. METHODS: In this multicentre cohort study (BEST2), patients with Barrett's oesophagus underwent the Cytosponge test before their surveillance endoscopy. We collected clinical and demographic data and tested Cytosponge samples for a molecular biomarker panel including three protein biomarkers (P53, c-Myc, and Aurora kinase A), two methylation markers (MYOD1 and RUNX3), glandular atypia, and TP53 mutation status. We used a multivariable logistic regression model to compute the conditional probability of dysplasia status. We selected a simple model with high classification accuracy and applied it to an independent validation cohort. The BEST2 study is registered with ISRCTN, number 12730505. FINDINGS: The discovery cohort consisted of 468 patients with Barrett's oesophagus and intestinal metaplasia. Of these, 376 had no dysplasia and 22 had high-grade dysplasia or intramucosal adenocarcinoma. In the discovery cohort, a model with high classification accuracy consisted of glandular atypia, P53 abnormality, and Aurora kinase A positivity, and the interaction of age, waist-to-hip ratio, and length of the Barrett's oesophagus segment. 162 (35%) of 468 of patients fell into the low-risk category and the probability of being a true non-dysplastic patient was 100% (99% CI 96-100) and the probability of having high-grade dysplasia or intramucosal adenocarcinoma was 0% (0-4). 238 (51%) of participants were classified as of moderate risk; the probability of having high-grade dysplasia was 14% (9-21). 58 (12%) of participants were classified as high-risk; the probability of having non-dysplastic endoscopic biopsies was 13% (5-27), whereas the probability of having high-grade dysplasia or intramucosal adenocarcinoma was 87% (73-95). In the validation cohort (65 patients), 51 were non-dysplastic and 14 had high-grade dysplasia. In this cohort, 25 (38%) of 65 patients were classified as being low-risk, and the probability of being non-dysplastic was 96·0% (99% CI 73·80-99·99). The moderate-risk group comprised 27 non-dysplastic and eight high-grade dysplasia cases, whereas the high-risk group (8% of the cohort) had no non-dysplastic cases and five patients with high-grade dysplasia. INTERPRETATION: A combination of biomarker assays from a single Cytosponge sample can be used to determine a group of patients at low risk of progression, for whom endoscopy could be avoided. This strategy could help to avoid overdiagnosis and overtreatment in patients with Barrett's oesophagus. FUNDING: Cancer Research UK.


Asunto(s)
Esófago de Barrett/diagnóstico , Citodiagnóstico/métodos , Medición de Riesgo/métodos , Adenocarcinoma/patología , Anciano , Esófago de Barrett/patología , Biomarcadores/análisis , Estudios de Casos y Controles , Progresión de la Enfermedad , Neoplasias Esofágicas/patología , Esofagoscopía , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
8.
PLoS Med ; 12(1): e1001780, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25634542

RESUMEN

BACKGROUND: Barrett's esophagus (BE) is a commonly undiagnosed condition that predisposes to esophageal adenocarcinoma. Routine endoscopic screening for BE is not recommended because of the burden this would impose on the health care system. The objective of this study was to determine whether a novel approach using a minimally invasive cell sampling device, the Cytosponge, coupled with immunohistochemical staining for the biomarker Trefoil Factor 3 (TFF3), could be used to identify patients who warrant endoscopy to diagnose BE. METHODS AND FINDINGS: A case-control study was performed across 11 UK hospitals between July 2011 and December 2013. In total, 1,110 individuals comprising 463 controls with dyspepsia and reflux symptoms and 647 BE cases swallowed a Cytosponge prior to endoscopy. The primary outcome measures were to evaluate the safety, acceptability, and accuracy of the Cytosponge-TFF3 test compared with endoscopy and biopsy. In all, 1,042 (93.9%) patients successfully swallowed the Cytosponge, and no serious adverse events were attributed to the device. The Cytosponge was rated favorably, using a visual analogue scale, compared with endoscopy (p < 0.001), and patients who were not sedated for endoscopy were more likely to rate the Cytosponge higher than endoscopy (Mann-Whitney test, p < 0.001). The overall sensitivity of the test was 79.9% (95% CI 76.4%-83.0%), increasing to 87.2% (95% CI 83.0%-90.6%) for patients with ≥3 cm of circumferential BE, known to confer a higher cancer risk. The sensitivity increased to 89.7% (95% CI 82.3%-94.8%) in 107 patients who swallowed the device twice during the study course. There was no loss of sensitivity in patients with dysplasia. The specificity for diagnosing BE was 92.4% (95% CI 89.5%-94.7%). The case-control design of the study means that the results are not generalizable to a primary care population. Another limitation is that the acceptability data were limited to a single measure. CONCLUSIONS: The Cytosponge-TFF3 test is safe and acceptable, and has accuracy comparable to other screening tests. This test may be a simple and inexpensive approach to identify patients with reflux symptoms who warrant endoscopy to diagnose BE.


Asunto(s)
Esófago de Barrett/diagnóstico , Endoscopía del Sistema Digestivo/instrumentación , Péptidos/metabolismo , Anciano , Esófago de Barrett/metabolismo , Esófago de Barrett/patología , Biomarcadores/análisis , Biomarcadores/metabolismo , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Péptidos/análisis , Sensibilidad y Especificidad , Factor Trefoil-3
9.
Inorg Chem ; 41(8): 2182-7, 2002 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-11952372

RESUMEN

Base-catalyzed cross condensation of dipropylmaleonitrile 1 with bis(dimethylamino)maleonitrile 2 in an equimolar ratio afforded the porphyrazines 3a, 4a, 5a, 6a and 7a. Subsequent demetalation of 5a with TFA followed by remetalation with Zn(OAc)(2) gave ligand 5c in good yield. Compound 5c was, in turn, selectively oxidized and further peripherally functionalized using Pt(PhCN)(2)Cl(2) and PdCl(2) to yield the novel seco solitaire porphyrazines 10a and 10b. The photophysical profiles of the seco solitaire porphyrazines 10a and 10b were evaluated by means of absorption, emission, and transient absorption spectroscopy. The new pigments 10a and 10b were found to be photochemically more stable than the solitaire complexes 3d and 3e and mediated the generation of singlet oxygen with quantum yields of 0.59 and 0.45, respectively.

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