39 research outputs found
Yield and morphology of Nopalea cochenillifera under N fertilization and biological inoculation
Received: August 15th, 2023 ; Accepted: October 30th, 2023 ; Published: November 9th, 2023 ;
Correspondence: [email protected]; [email protected] objective was to evaluate the effect of inoculation with Azospirillum brasilense
and levels of nitrogen fertilization on the productive aspects of the spineless cactus (Nopalea
cochenillifera). The experiment was carried in Ribeirão do Largo, Southwest region of the state
of Bahia, from April 2019 to April 2020. The experiment was carried out in a 2×4 factorial, in a
randomized block design with eight treatments and four replications. The treatments consisted of
the absence or inoculation with Azospirillum brasilense and nitrogen fertilization levels 0, 50,
100 and 150 kg–
¹ of N ha–¹
. There was a positive effect for the use of the bacteria on cladode area
index, height, number of secondary, tertiary and total cladodes, total weight for cladodes of all
orders and also for final weight per ha–¹
. There was a significant effect of the use of the inoculant
for the levels of total soluble sugars and starch, where there was a decrease in the values for the
treatments submitted to the use of the bacteria. There was a quadratic effect for the weight of the
tertiary cladodes, number of tertiary cladodes and total of spineless cactus when submitted to
nitrogen fertilization levels. There was a linear test for cladodes area index when nitrogen
fertilization was used. The use of Azospirillum brasilense is positive for the cultivation of
spineless cactus, improving development and increasing crop productivity
Carbohydrate and protein metabolism of marandu grass affected by nitrogen fertilisation and number of cuts
Received: June 18th, 2023 ; Accepted: September 30th, 2023 ; Published: October 23rd, 2023 ; Correspondence: [email protected] the metabolism of tropical grasses in response to management practises
imposed in pastoral environments allows for improvements in the management and use of mineral
fertilisers. This study aimed to quantify metabolite content in different plant parts of Marandu
grass (Urochloa brizantha), with a specific focus on the influence of nitrogen fertilisation and its
effects following successive cuts. The treatments corresponded to four nitrogen (N) rates
(0, 75, 150, and 225 kg N ha-1
) and the number of cuts (one, two and three cuts). The plants were
fractionated into leaves, stems, and roots to assess the content of water-soluble carbohydrates
(WSC), starch, albumin, globulin, prolamin, and glutelin content. N fertilisation influenced the
WSC and starch content in different parts of the plant, varying according to the cuts made. In the
leaves and roots, fertilisation reduced the content of WSC and starch with one cut, as these were
utilised as energy sources for assimilating the excess nitrogen in the soil. There was an increase
in the concentration of all protein groups with nitrogen fertilisation in all parts of the plant with
one cut. In plants cut two and three times, N fertilisation led to specific increases and decreases
in different parts of the plants as an adaptive strategy for allocating resources as the number of
cuts increased. Our results broaden our understanding of carbohydrate and protein metabolism in
tropical grasses, thereby providing subsidies for the rational use of nitrogen fertilisers
Cardiovascular risk reduction with liraglutide: An exploratory mediation analysis of the leader trial
OBJECTIVE The Liraglutide Effect and Action in Diabetes: Evaluation of Cardiovascular Outcome Results (LEADER) trial (ClinicalTrials.gov reg. no. NCT01179048) demonstrated a reduced risk of cardiovascular (CV) events for patients with type 2 diabetes who received the glucagon-like peptide 1 receptor agonist liraglutide versus placebo. The mechanisms behind this CV benefit remain unclear. We aimed to identify potential mediators for the CV benefit observed with liraglutide in the LEADER trial. RESEARCH DESIGN AND METHODS We performed exploratory analyses to identify potential mediators of the effect of liraglutide on major adverse CV events (MACE; composite of CV death, nonfatal myocardial infarction, or nonfatal stroke) from the following candidates: Glycated hemoglobin (HbA1c), body weight, urinary albumin-to-creatinine ratio (UACR), confirmed hypoglycemia, sulfonylurea use, insulin use, systolic blood pressure, and LDL cholesterol. These candidates were selected as CV risk factors on which liraglutide had an effect in LEADER such that a reduction in CV risk might result. We used two methods based on a Cox proportional hazards model and the new Vansteelandt method designed to use all available information from the mediator and to control for confounding factors. RESULTS Analyses using the Cox methods and Vansteelandt method indicated potential mediation by HbA1c (up to 41% and 83% mediation, respectively) and UACR (up to 29% and 33% mediation, respectively) on the effect of liraglutide on MACE. Mediation effects were small for other candidates. CONCLUSIONS These analyses identify HbA1c and, to a lesser extent, UACR as potential mediators of the CV effects of liraglutide. Whether either is a marker of an unmeasured factor or a true mediator remains a key question that invites further investigation
Effects of liraglutide on cardiovascular outcomes in patients with type 2 diabetes mellitus with or without history of myocardial infarction or stroke: Post hoc analysis from the leader trial
Background: The glucagon-like peptide-1 analog liraglutide reduced cardiovascular events and mortality in patients with type 2 diabetes mellitus in the LEADER trial (Liraglutide and Cardiovascular Outcomes in Type 2 Diabetes). In a post hoc analysis, we evaluated the efficacy of liraglutide in those with and without a history of myocardial infarction (MI) and/or stroke. Methods: LEADER was a randomized trial of liraglutide (1.8 mg or maximum tolerated dose) versus placebo in 9340 patients with type 2 diabetes mellitus and high cardiovascular risk, with a median follow-up of 3.8 years. The primary outcome was a composite of cardiovascular death, nonfatal MI, or nonfatal stroke (major adverse cardiovascular events). Risk groups in this post hoc analysis were defined by history of MI/stroke, established atherosclerotic cardiovascular disease without MI/stroke, or cardiovascular risk factors alone. Results: Of the 9340 patients, 3692 (39.5%) had a history of MI/stroke, 3083 (33.0%) had established atherosclerotic cardiovascular disease without MI/stroke, and 2565 (27.5%) had risk factors alone. Major adverse cardiovascular events occurred in 18.8% of patients with a history of MI/stroke (incidence rate, 5.0 per 100 patient-years), 11.6% of patients with established atherosclerotic cardiovascular disease without MI/stroke (incidence rate, 3.0 per 100 patient-years), and 9.8% of patients with cardiovascular risk factors alone (incidence rate, 2.6 per 100 patient-years). Liraglutide reduced major adverse cardiovascular events in patients with a history of MI/stroke (322 of 1865 [17.3%] versus 372 of 1827 patients [20.4%]; hazard ratio, 0.85; 95% CI, 0.73-0.99) and in those with established atherosclerotic cardiovascular disease without MI/stroke (158 of 1538 [10.3%] versus 199 of 1545 patients [12.9%]; hazard ratio, 0.76; 95% CI, 0.62-0.94) compared with placebo. In patients with risk factors alone, the hazard ratio for liraglutide versus placebo was 1.08 (95% CI, 0.84-1.38, Pinteraction=0.11). Similar results were seen for secondary outcomes across risk groups. Conclusions: In this post hoc analysis of patients with type 2 diabetes mellitus and high cardiovascular risk, liraglutide reduced cardiovascular outcomes both in patients with a history of MI/stroke and in those with established atherosclerotic cardiovascular disease without MI/stroke. The cardiovascular effect appeared neutral in patients with cardiovascular risk factors alone
Phi meson production in Au+Au and p+p collisions at sqrt (s)=200 GeV
We report the STAR measurement of Phi meson production in Au+Au and p+p
collisions at sqrt (s)=200 GeV. Using the event mixing technique, the Phi
spectra and yields are obtained at mid-rapidity for five centrality bins in
Au+Au collisions and for non-singly-diffractive p+p collisions. It is found
that the Phi transverse momentum distributions from Au+Au collisions are better
fitted with a single-exponential while the p+p spectrum is better described by
a double-exponential distribution. The measured nuclear modification factors
indicate that Phi production in central Au+Au collisions is suppressed relative
to peripheral collisions when scaled by the number of binary collisions. The
systematics of versus centrality and the constant Phi/K- ratio versus beam
species, centrality, and collision energy rule out kaon coalescence as the
dominant mechanism for Phi production.Comment: 6 pages, 3 figures, submitted to Phys. Rev. Let
Energy and system size dependence of \phi meson production in Cu+Cu and Au+Au collisions
We study the beam-energy and system-size dependence of \phi meson production
(using the hadronic decay mode \phi -- K+K-) by comparing the new results from
Cu+Cu collisions and previously reported Au+Au collisions at \sqrt{s_NN} = 62.4
and 200 GeV measured in the STAR experiment at RHIC. Data presented are from
mid-rapidity (|y|<0.5) for 0.4 < pT < 5 GeV/c. At a given beam energy, the
transverse momentum distributions for \phi mesons are observed to be similar in
yield and shape for Cu+Cu and Au+Au colliding systems with similar average
numbers of participating nucleons. The \phi meson yields in nucleus-nucleus
collisions, normalised by the average number of participating nucleons, are
found to be enhanced relative to those from p+p collisions with a different
trend compared to strange baryons. The enhancement for \phi mesons is observed
to be higher at \sqrt{s_NN} = 200 GeV compared to 62.4 GeV. These observations
for the produced \phi(s\bar{s}) mesons clearly suggest that, at these collision
energies, the source of enhancement of strange hadrons is related to the
formation of a dense partonic medium in high energy nucleus-nucleus collisions
and cannot be alone due to canonical suppression of their production in smaller
systems.Comment: 20 pages and 5 figure
Experimental and Theoretical Challenges in the Search for the Quark Gluon Plasma: The STAR Collaboration's Critical Assessment of the Evidence from RHIC Collisions
We review the most important experimental results from the first three years
of nucleus-nucleus collision studies at RHIC, with emphasis on results from the
STAR experiment, and we assess their interpretation and comparison to theory.
The theory-experiment comparison suggests that central Au+Au collisions at RHIC
produce dense, rapidly thermalizing matter characterized by: (1) initial energy
densities above the critical values predicted by lattice QCD for establishment
of a Quark-Gluon Plasma (QGP); (2) nearly ideal fluid flow, marked by
constituent interactions of very short mean free path, established most
probably at a stage preceding hadron formation; and (3) opacity to jets. Many
of the observations are consistent with models incorporating QGP formation in
the early collision stages, and have not found ready explanation in a hadronic
framework. However, the measurements themselves do not yet establish
unequivocal evidence for a transition to this new form of matter. The
theoretical treatment of the collision evolution, despite impressive successes,
invokes a suite of distinct models, degrees of freedom and assumptions of as
yet unknown quantitative consequence. We pose a set of important open
questions, and suggest additional measurements, at least some of which should
be addressed in order to establish a compelling basis to conclude definitively
that thermalized, deconfined quark-gluon matter has been produced at RHIC.Comment: 101 pages, 37 figures; revised version to Nucl. Phys.
Respostas fisiológicas em cultivares de soja submetidas ao alagamento em diferentes estádios
Energy dependence of charged pion, proton and anti-proton transverse momentum spectra for Au+Au collisions at \sqrt{s_NN} = 62.4 and 200 GeV
We study the energy dependence of the transverse momentum (pT) spectra for
charged pions, protons and anti-protons for Au+Au collisions at \sqrt{s_NN} =
62.4 and 200 GeV. Data are presented at mid-rapidity (|y| < 0.5) for 0.2 < pT <
12 GeV/c. In the intermediate pT region (2 < pT < 6 GeV/c), the nuclear
modification factor is higher at 62.4 GeV than at 200 GeV, while at higher pT
(pT >7 GeV/c) the modification is similar for both energies. The p/pi+ and
pbar/pi- ratios for central collisions at \sqrt{s_NN} = 62.4 GeV peak at pT ~ 2
GeV/c. In the pT range where recombination is expected to dominate, the p/pi+
ratios at 62.4 GeV are larger than at 200 GeV, while the pbar/pi- ratios are
smaller. For pT > 2 GeV/c, the pbar/pi- ratios at the two beam energies are
independent of pT and centrality indicating that the dependence of the pbar/pi-
ratio on pT does not change between 62.4 and 200 GeV. These findings challenge
various models incorporating jet quenching and/or constituent quark
coalescence.Comment: 19 pages and 6 figure
Search for Tensor, Vector, and Scalar Polarizations in the Stochastic Gravitational-Wave Background
The detection of gravitational waves with Advanced LIGO and Advanced Virgo has enabled novel tests of general relativity, including direct study of the polarization of gravitational waves. While general relativity allows for only two tensor gravitational-wave polarizations, general metric theories can additionally predict two vector and two scalar polarizations. The polarization of gravitational waves is encoded in the spectral shape of the stochastic gravitational-wave background, formed by the superposition of cosmological and individually unresolved astrophysical sources. Using data recorded by Advanced LIGO during its first observing run, we search for a stochastic background of generically polarized gravitational waves. We find no evidence for a background of any polarization, and place the first direct bounds on the contributions of vector and scalar polarizations to the stochastic background. Under log-uniform priors for the energy in each polarization, we limit the energy densities of tensor, vector, and scalar modes at 95% credibility to Ω0T<5.58×10-8, Ω0V<6.35×10-8, and Ω0S<1.08×10-7 at a reference frequency f0=25 Hz. © 2018 American Physical Society