1,345 research outputs found
Superpropagators for explicitly broken 3D-supersymmetric theories
A systematic algorithm to derive superpropagators in the case of either
explicitly or spontaneously broken supersymmetric three-dimensional theories is
presented. We discuss how the explicit breaking terms that are introduced at
tree-level induce 1-loop radiative corrections to the effective action. We also
point out that the renormalisation effects and the breaking-inducing-breaking
mechanism become more immediate whenever we adopt the shifted superpropagators
discussed in this letter.Comment: 6 pages, LaTex, references added. To appear in Phys.Lett.
Phenolics: from chemistry to biology
In recent years, few classes of natural products have received as much attention
as phenolics and polyphenols. This special issue of Molecules, “Phenolics and
Polyphenolics”, is a remarkable confirmation of this trend. Several aspects related to
phenolics chemistry, comprising the several classes, will be discussed. In addition, the
increasing interest in phenolics’ biological activities is covered, and several works
addressing this matter are referred
Optimizing the establishment of bean and maize varieties in tropical environments
7th International Conference on Agricultural and Biological Sciences (ABS 2021)The successful establishment of any crop is the initial indication of its productivity.
Optimizing the establishment of a crop implies ensuring generalized, fast and concentrated
emergence. This work studies optimal temperature ranges, under non-limiting water conditions,
for both germination and emergence of two bean (Phaseolus vulgaris L.) varieties (catarina and
ervilha) and two maize (Zea mays L.) varieties (matuba and sam3).
Experiments used a thermogradient plate. Petri dishes were used for germination experiments.
Emergence experiments were performed in aluminium containers filled with packed portions of
a sandy loam clay textured soil. Size, speed and spread of both germination and emergence were
measured at different temperatures by Cu-CuNi thermocouples.
Thermal ranges with optimal counts of both germination and emergence [To1
sz, To2
sz] were
identified using a flattened bell curve function. Speed was maximized for either germination or
emergence over thermal ranges [To1
sp, To2
sp] defined using the plateau model to relate either
germination or emergence rates with temperature. Ranges along which the spread of both
germination and emergence are nearly minimized [To1
sd, To2
sd] were identified with the aid of
even-degree polynomials. The intersection of all three thermal ranges gave rise to optimal
temperature ranges [To1, To2] for germination (OTRG) of the four varieties in study and for
emergence (OTRE) of three of them. In general, the lower thermal limit of OTRG was determined
by speed (To1 = To1
sp) and the upper thermal limit by size (To2 = To2
sz). OTRE begins at To1
sp for
ervilha and sam3 and at To1
sd for catarina and ends at To2
sz for catarina and at To2
sd for the others.
The endpoints and length of both the OTRG and OTRE were also found to be crop-dependent.
Thus, farmers can choose between crops and optimize their establishment. The identification of
these parameters may also be useful in assessing weather forecasts and for warning systems and
agro-climatic zoning. The influence of the substrate used in each experiment was also discussedinfo:eu-repo/semantics/publishedVersio
Seed loss of bean and maize varieties as a function of temperature and irrigation levels
PaperMinimizing seed loss is one of the main goals for a successful crop establishment.
The main purpose of this research was to model seed loss of tropically relevant crops,
measured both at germination and at emergence, as a function of temperature and irrigation
level. Four bean varieties (catarina, ervilha, manteiga and sondeyombua) and two maize
varieties (matuba and sam3) were studied. Experiments were performed in a controlled
environment using a thermogradient plate. Temperatures were monitored with Cu-CuNi
thermocouples. Seed loss under optimal hydric conditions was simulated at different
temperatures, depending on the variety. Eight irrigation levels (6, 7, 8, 9, 10, 12, 15 and 18
mm) were used to simulate the effects of irrigation on losses under optimal thermal conditions.
Temperature ranges suitable to the thermal response of each crop were used. A sandy loamclay
textured soil was used in both germination and emergence experiments whereas filter
papers in Petri dishes were used for germination experiments only.
Seed loss was minimal along wide thermal or irrigation ranges and increased toward the lowest
and highest temperatures and, in most cases, also towards the extreme irrigation levels. The use
of even-degree polynomial models successfully identified thermal [T1, T2] and irrigation [I1, I2]
ranges over which losses did not exceed the maximum acceptable losses (m.a.l.). The
endpoints and length of those ranges were found to be crop-dependent. Differences between
estimated polynomial model parameters, for both germination and emergence (Lmin, Tmin or Imin,
and ct or ci), highlighted the role of soil in rising the seedling towards the surface. Germination
size as a function of temperature also depended on the substrate used.
Both the range lengths and endpoints can be of interest for decision-making regarding crops or
varieties to be used or in identifying sowing times for a given crop or variety. Farm weather
forecast and warning systems of different nature and agro-climatic zoning may also benefit
with the knowledge of these parametersinfo:eu-repo/semantics/publishedVersio
The Social and Economic Impact of Covid-19 on Family Functioning and Well-Being: Where do we go from here?
A growing body of research demonstrates that COVID-19 has had a profound impact on family functioning and well-being in a range of countries. The fear and uncertainty of the health risks, in addition to the stress from ensuing restrictions and constraints on everyday life caused major disruptions, impacting the financial, emotional, and physical well-being of adults and children alike. In this report, we summarize the current literature on the impact of COVID-19 disruption to family functioning and economic well-being as a context for this special issue. Our findings indicate that while the pandemic may have caused a reallocation of intra-familial tasks, a large gender disparity remains regarding the proportion of domestic work and childcare. The pandemic disproportionally impacted lower-income families, families from ethnic minority and vulnerable groups, and women. Finally, the financial impacts of the emergence in Spring of 2020 have strained family relationships, although the effects depend to a large extent on quality of the relationships and family well-being before COVID-19. To address the long-term bidirectional effects of the pandemic on family well-being and the well-being of the global economy calls for research that crosses disciplinary divides. © 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature
Alkemio: association of chemicals with biomedical topics by text and data mining
The PubMed(R) database of biomedical citations allows the retrieval of scientific articles studying the function of chemicals in biology and medicine. Mining millions of available citations to search reported associations between chemicals and topics of interest would require substantial human time. We have implemented the Alkemio text mining web tool and SOAP web service to help in this task. The tool uses biomedical articles discussing chemicals (including drugs), predicts their relatedness to the query topic with a naïve Bayesian classifier and ranks all chemicals by P-values computed from random simulations. Benchmarks on seven human pathways showed good retrieval performance (areas under the receiver operating characteristic curves ranged from 73.6 to 94.5%). Comparison with existing tools to retrieve chemicals associated to eight diseases showed the higher precision and recall of Alkemio when considering the top 10 candidate chemicals. Alkemio is a high performing web tool ranking chemicals for any biomedical topics and it is free to non-commercial users. Availability: http://cbdm.mdc-berlin.de/∼medlineranker/cms/alkemio
Resposta da couve Tronchuda (Brassica oleracea var costata) à aplicação de azoto, boro e um fertilizante orgânico para agricultura biológica
Evaluation of a numerical method to predict the polyphenol content in monovarietal olive oils
Three monovarietal virgin olive oils obtained from olives grown under biological agricultural system, in Portugal, with different ripening
stages, were studied in what concerns the parameters usually related with oxidation status (total polyphenols, tocopherols, chlorophylls
and carotenoids, peroxide values, oxidative stability, specific extinction coefficients K232 and K270 and titratable acidity). A total
of 18 samples were analyzed: seven from Cv. Cobranc¸osa (maturation indices 1–7), five from Cv. Madural (maturation indices 3–7) and
six from Cv. Verdeal Transmontana (maturation indices 1–6). Oxidative stability and polyphenols profile presented high correlation coef-
ficients. Given this high correlation, a numerical method was developed and evaluated to predict total polyphenols contents in olive oil.
The method is based on the kinetic equation of the oxidation process in the presence of antioxidants and on Rancimat profiles. Total
polyphenols contents obtained with this method were similar to those obtained by the Folin-Ciocalteau method
- …