613 research outputs found
Organic Orchard Floor Management Systems for Apple Effect on Rootstock Performance in the Midwestern United States
In organic apple production systems, orchard floor management is of prime importance because it determines weed management and soil fertility. In this experiment,
we evaluated the response of the cultivar Pacific Gala on three rootstocks of different vigor: M.9 NAKB 337, M.9 RN 29, and Supporter 4 (in respective order of vigor
from dwarfing to semivigorous). The rootstocks were also evaluated for the response to three orchard floor management systems (OFMSs): mulching using alfalfa hay, flame burning, and shallow strip tillage using the Swiss sandwich system (SSS). The experiment was conducted in an experimental orchard planted in 2000
Soil properties under different orchard floor management systems for organic apple production
Orchard floor management impacts soil conditions and thus tree performance. This research was initiated to investigate the effects of alternative orchard floor management systems compatible with organic production on soil parameters using the“Pacific Gala” apple cultivar (Malus × domestica Borkh.) on three rootstocks of varying vigor. Alfalfa hay mulch, propane flame burner, and Swiss sandwich system(combination of resident vegetation and tilled strips)were compared from 2001 to 2005. These treatments were applied to tree rows which provided different vegetation-free areas. Contrasting additions of organic matter were evaluated for their effect on soil organic matter (SOM), C content, nitrate and ammonium availability, moisture, and soil food web through nematode
populations. Laboratory incubations to determine C and N mineralization potentials were performed. During this time period, SOM increased under the mulched soil and slightly less under the Swiss sandwich system (SSS) but in this last case without external inputs. Carbon and N pools were not impacted by flame burning (FL) but were enhanced by alfalfa hay mulch (MU) and to a lesser extent by SSS. Nitrate-N content in soil under MU increased between five and ten times compared to SSS and FL. Total number of nematodes was
higher for SSS and MU compared with FL treatment; however, SSS had the most structured soil food web, an important sustainability trait, while MU had the leas
Plasma visfatin and adiponectin concentrations in physically active adolescent girls: relationships with insulin sensitivity and body composition variables
The purpose of this study was to evaluate the associations of visfatin and adiponectin concentrations with insulin resistance and body composition in regularly physically active pubertal girls . In 129 girls, aged 13-15 years (pubertal stages 3-5), visfatin, adiponectin, insulin resistance measured with homeostasis model assessment (HOMA) and body composition measured with dual-x ray absorptiometry were evaluated. Visfatin concentration was related to HOMA and overall adiposity (body mass index, fat mass) markers, whereas adiponectin concentration was related to overall adiposity (fat mass), central adiposity (trunk fat) and fat free mass values. These relationships remained significant (p >0.05) after adjusting for pubertal stage. Visfatin was independently related to body mass index (beta=0.936, p=0.0001) and HOMA (beta=0.444, p=0.039) indices, whereas adiponectin was indipendently related to fat free mass (beta=0.468;P=0.042) values. In conclusion visfatin could be related to insulin resistance and overall adiposity indices, whereas adiponectin was related to different body composition values in regularly physically active puberal girls
Translingual neurostimulation combined with physical therapy to improve walking and balance in multiple sclerosis (NeuroMSTraLS): Study protocol for a randomized controlled trial
INTRODUCTION: Physical rehabilitation restores lost function and promotes brain plasticity in people with Multiple Sclerosis (MS). Research groups worldwide are testing the therapeutic effects of combining non-invasive neuromodulation with physical therapy (PT) to further improve functional outcomes in neurological disorders but with mixed results. Whether such devices enhance function is not clear. We present the rationale and study design for a randomized controlled trial evaluating if there is additional benefit to the synergistic pairing of translingual neurostimulation (TLNS) with PT to improve walking and balance in MS.
METHODS AND ANALYSIS: A parallel group [PT + TLNS or PT + Sham], quadruple-blinded, randomized controlled trial. Participants (N = 52) with gait and balance deficits due to relapsing-remitting or progressive MS, who are between 18 and 70 years of age, will be recruited through patient registries in Newfoundland & Labrador and Saskatchewan, Canada. All participants will receive 14 weeks of PT while wearing either a TLNS or sham device. Dynamic Gait Index is the primary outcome. Secondary outcomes include fast walking speed, subjective ratings of fatigue, MS impact, and quality of life. Outcomes are assessed at baseline (Pre), after 14 weeks of therapy (Post), and 26 weeks (Follow Up). We employ multiple methods to ensure treatment fidelity including activity and device use monitoring. Primary and secondary outcomes will be analyzed using linear mixed-effect models. We will control for baseline score and site to test the effects of Time (Post vs. Follow-Up), Group and the Group x Time interaction as fixed effects. A random intercept of participant will account for the repeated measures in the Time variable. Participants must complete the Post testing to be included in the analysis.
ETHICS AND DISSEMINATION: The Human Research Ethics Boards in Newfoundland & Labrador (HREB#2021.085) & Saskatchewan (HREB Bio 2578) approved the protocol. Dissemination avenues include peer-reviewed journals, conferences and patient-oriented communications
Supplemental selenium source on gut health: Insights on fecal microbiome and fermentation products of growing puppies
Selenium is an essential trace element that can modulate the gut microbiome with an impact on host health. The present study aimed to evaluate the effects of organic (selenium-enriched yeast) vs inorganic (sodium selenite) selenium source on fecal end-fermentation products and gut microbiome of puppies from 20 to 52 weeks of age. Alpha and beta diversity of the gut bacterial community were affected by age but not by gender or selenium source. The relative abundance of taxa was differently affected by age, and the DNA concentration of all selected bacterial groups increased with age, although total volatile fatty acids (VFA), acetate, propionate, caproate and lactate concentrations decreased. Organic selenium was associated with a higher concentration of total VFA, propionate and butyrate, a higher number of DNA copies of Lactobacillus, and a trend to lower DNA copies of Escherichia coli. Effects on fecal microbiome during growth differed with selenium source. Females had higher fecal end-fermentation products related to protein degradation, whereas males had higher DNA concentration of Bifidobacterium. Organic selenium might be beneficial over inorganic for dog food supplementation due to the positive modulation of the gut microbiome observed in puppies
Coseismic and post-seismic slip of the 2009 L'Aquila (central Italy) MW 6.3 earthquake and implications for seismic potential along the Campotosto fault from joint inversion of high-precision levelling, InSAR and GPS data
After the April 6th 2009 MW 6.3 (ML 5.9) L'Aquila earthquake (central Italy), we re-measured more than 100 km
of high-precision levelling lines in the epicentral area. The joint inversion of the levelling measurements with
InSAR and GPS measurements, allowed us to derive new coseismic and post-seismic slip distributions and to de-
scribe, with high resolution details on surface displacements, the activation and the slip distribution of a second-
ary fault during the aftershock sequence that struck the Campotosto area (major event MW 5.2). Coseismic slip on
the Paganica fault occurred on one main asperity, while the afterslip distribution shows a more complex pattern,
occurring on three main patches, including both slips on the shallow portions and on the deeper parts of the rup-
ture plane. The comparison between coseismic and post-seismic slip distributions strongly suggests that afterslip
was triggered at the edges of the coseismic asperity. The activation of a segment of the Campotosto fault during
the aftershock sequence, with a good correlation between the estimated slipping area, moment release and
distribution of aftershocks, raises the opportunity to discuss the local seismic hazard following the occurrence
of the 2009 L'Aquila mainshock. The Campotosto fault appears capable of generating earthquakes as large as his-
torical events in the region (M N 6.5) or as small as the ones associated with the 2009 sequence. In the case that
the Campotosto fault is accumulating a significant portion of the current interseismic deformation, the 2009 MW
N 5 events will have released only a small amount of the accumulated elastic strain, and then a significant hazard
still remains in the area. Continuing geodetic monitoring and a densification of the GPS networks in the region are
therefore needed to estimate the tectonic loading across the different recognized active fault systems in this part
of the Apennines.Published168-1852T. Tettonica attivaJCR Journalrestricte
Geographically widespread invasive meningococcal disease caused by a ciprofloxacin resistant non-groupable strain of the ST-175 clonal complex.
INTRODUCTION: Invasive meningococcal disease (IMD) caused by non-serogroupable (NG) strains mainly affects immunocompromised individuals. Reduced susceptibility to penicillin in meningococci is increasing in Europe but ciprofloxacin resistance remains rare. In 2019, three travel-related meningococcal disease cases caused by a ciprofloxacin-resistant NG strain were identified in England, leading Germany to report four additional IMD cases (2016 to 2019). We describe these and newly identified cases and characterise the strain responsible. METHODS: Cases were identified as part of national surveillance and by analysing available genomes using PubMLST tools. RESULTS: Of the cases identified in England in 2019, two geographically distinct cases developed conjunctivitis after returning from Mecca (Kingdom of Saudi Arabia) and a third linked case presented with IMD. Of the four cases from Germany, three occurred in asylum seekers - two familial and a further geographically distinct case. Further IMD cases were identified in Italy (n = 2; 2017-2018), Sweden (n = 1; 2016) and England (n = 1; 2015). A single ST-175 clonal complex (cc175) strain with genosubtype P1.22-11,15-25 was responsible. Decreased susceptibility to penicillin was widespread with three ciprofloxacin resistant subclusters. Constituent isolates were potentially covered by subcapsular vaccines. CONCLUSION: This disease associated NG cc175 strain exhibits resistance to antibiotics commonly used to prevent IMD but is potentially covered by subcapsular (meningococcal B) vaccines
Passing to the Limit in a Wasserstein Gradient Flow: From Diffusion to Reaction
We study a singular-limit problem arising in the modelling of chemical
reactions. At finite {\epsilon} > 0, the system is described by a Fokker-Planck
convection-diffusion equation with a double-well convection potential. This
potential is scaled by 1/{\epsilon}, and in the limit {\epsilon} -> 0, the
solution concentrates onto the two wells, resulting into a limiting system that
is a pair of ordinary differential equations for the density at the two wells.
This convergence has been proved in Peletier, Savar\'e, and Veneroni, SIAM
Journal on Mathematical Analysis, 42(4):1805-1825, 2010, using the linear
structure of the equation. In this paper we re-prove the result by using solely
the Wasserstein gradient-flow structure of the system. In particular we make no
use of the linearity, nor of the fact that it is a second-order system. The
first key step in this approach is a reformulation of the equation as the
minimization of an action functional that captures the property of being a
curve of maximal slope in an integrated form. The second important step is a
rescaling of space. Using only the Wasserstein gradient-flow structure, we
prove that the sequence of rescaled solutions is pre-compact in an appropriate
topology. We then prove a Gamma-convergence result for the functional in this
topology, and we identify the limiting functional and the differential equation
that it represents. A consequence of these results is that solutions of the
{\epsilon}-problem converge to a solution of the limiting problem.Comment: Added two sections, corrected minor typos, updated reference
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