352 research outputs found
Automated and manual layflat tubing for irrigation and conveyance
Layflat tubing has been used for a number of years for irrigation (Hansen, 1954; Lauritzen, 1957;
Humpherys and Lauritzen, 1964). Most tubing presently used in the United States is a low-cost, thin-wall,
non-reinforced tubing with a one- or two-year life expectancy. Layflat tubing is used both for
distribution to individual furrows, when equipped with outlets, and for conveyance. It has many of
the advantages of rigid surface irrigation pipe and can be used as an alternative to rigid surface pipe
in most situations. It is particularly well-suited for dividing fields with long irrigation run lengths into
shorter run lengths
Spring-Operated Semi-automatic Irrigation Valves
TORSION spring operators for standard low pressure
butterfly type irrigation valves are described. These
are used with 24-h timers to semiautomate gated pipe
irrigation systems and are particularly well suited for use
with flow-thru single pipeline systems. They are presently
marketed in 150 mm (6 in.), 200 mm (8 in.) and 250 mm
(10 in.) diameter sizes
Unitary chiral dynamics in J/Psi to VPP decays and the role of scalar mesons
We make a theoretical study of the J/Psi decays into \omega\pi\pi,
\phi\pi\pi, \omega K \bar{K} and \phi K\bar{K} using the techniques of the
chiral unitary approach stressing the important role of the scalar resonances
dynamically generated through the final state interaction of the two
pseudoscalar mesons. We also discuss the importance of new mechanisms with
intermediate exchange of vector and axial-vector mesons and the role played by
the OZI rule in the J/\Psi\phi\pi\pi vertex, quantifying its effects. The
results nicely reproduce the experimental data for the invariant mass
distributions in all the channels considered.Comment: 29 pages, 10 figure
decay within unitarized chiral perturbation theory
We improve the calculations of the decay
within the context of meson chiral lagrangians. We use a chiral unitary
approach for the meson-meson interaction, thus generating the
resonance and fixing the longstanding sign ambiguity on its contribution. This
also allows us to calculate the loops with one vector meson exchange, thus
removing a former source of uncertainty. In addition we ensure the consistency
of the approach with other processes. First, by using vector meson dominance
couplings normalized to agree with radiative vector meson decays. And, second,
by checking the consistency of the calculations with the related reaction. We find an decay width
of eV, in clear disagreement with published data but in
remarkable agreement with the most recent measurement.Comment: 15 pages, 10 figures, published versio
The Ultrashort Mental Health Screening Tool Is a Valid and Reliable Measure With Added Value to Support Decision-making
BACKGROUND: Mental health influences symptoms, outcomes, and decision-making in musculoskeletal healthcare. Implementing measures of mental health in clinical practice can be challenging. An ultrashort screening tool for mental health with a low burden is currently unavailable but could be used as a conversation starter, expectation management tool, or decision support tool.QUESTIONS/PURPOSES: (1) Which items of the Pain Catastrophizing Scale (PCS), Patient Health Questionnaire (PHQ-4), and Brief Illness Perception Questionnaire (B-IPQ) are the most discriminative and yield a high correlation with the total scores of these questionnaires? (2) What is the construct validity and added clinical value (explained variance for pain and hand function) of an ultrashort four-item mental health screening tool? (3) What is the test-retest reliability of the screening tool? (4) What is the response time for the ultrashort screening tool?METHODS: This was a prospective cohort study. Data collection was part of usual care at Xpert Clinics, the Netherlands, but prospective measurements were added to this study. Between September 2017 and January 2022, we included 19,156 patients with hand and wrist conditions. We subdivided these into four samples: a test set to select the screener items (n = 18,034), a validation set to determine whether the selected items were solid (n = 1017), a sample to determine the added clinical value (explained variance for pain and hand function, n = 13,061), and a sample to assess the test-retest reliability (n = 105). Patients were eligible for either sample if they completed all relevant measurements of interest for that particular sample. To create an ultrashort screening tool that is valid, reliable, and has added value, we began by picking the most discriminatory items (that is, the items that were most influential for determining the total score) from the PCS, PHQ-4, and B-IPQ using chi-square automated interaction detection (a machine-learning algorithm). To assess construct validity (how well our screening tool assesses the constructs of interest), we correlated these items with the associated sum score of the full questionnaire in the test and validation sets. We compared the explained variance of linear models for pain and function using the screening tool items or the original sum scores of the PCS, PHQ-4, and B-IPQ to further assess the screening tool's construct validity and added value. We evaluated test-retest reliability by calculating weighted kappas, ICCs, and the standard error of measurement.RESULTS: We identified four items and used these in the screening tool. The screening tool items were highly correlated with the PCS (Pearson coefficient = 0.82; p < 0.001), PHQ-4 (0.87; p < 0.001), and B-IPQ (0.85; p < 0.001) sum scores, indicating high construct validity. The full questionnaires explained only slightly more variance in pain and function (10% to 22%) than the screening tool did (9% to 17%), again indicating high construct validity and much added clinical value of the screening tool. Test-retest reliability was high for the PCS (ICC 0.75, weighted kappa 0.75) and B-IPQ (ICC 0.70 to 0.75, standard error of measurement 1.3 to 1.4) items and moderate for the PHQ-4 item (ICC 0.54, weighted kappa 0.54). The median response time was 43 seconds, against more than 4 minutes for the full questionnaires.CONCLUSION: Our ultrashort, valid, and reliable screening tool for pain catastrophizing, psychologic distress, and illness perception can be used before clinician consultation and may serve as a conversation starter, an expectation management tool, or a decision support tool. The clinical utility of the screening tool is that it can indicate that further testing is warranted, guide a clinician when considering a consultation with a mental health specialist, or support a clinician in choosing between more invasive and less invasive treatments. Future studies could investigate how the tool can be used optimally and whether using the screening tool affects daily clinic decisions.LEVEL OF EVIDENCE: Level II, diagnostic study.</p
Paternal Diet Defines Offspring Chromatin State and Intergenerational Obesity
The global rise in obesity has revitalized a search for genetic and epigenetic factors underlying the disease. We present a Drosophila model of paternal-diet-induced intergenerational metabolic reprogramming (IGMR) and identify genes required for its encoding in offspring. Intriguingly, we find that as little as 2 days of dietary intervention in fathers elicits obesity in offspring. Paternal sugar acts as a physiological suppressor of variegation, desilencing chromatin-state-defined domains in both mature sperm and in offspring embryos. We identify requirements for H3K9/K27me3-dependent reprogramming of metabolic genes in two distinct germline and zygotic windows. Critically, we find evidence that a similar system may regulate obesity susceptibility and phenotype variation in mice and humans. The findings provide insight into the mechanisms underlying intergenerational metabolic reprogramming and carry profound implications for our understanding of phenotypic variation and evolution
Stringent or nonstringent complete remission and prognosis in acute myeloid leukemia:a Danish population-based study
Key Points
sCR and non-sCR in acute myeloid leukemia are associated with different prognoses. Three lineage blood cell recoveries have independent impacts on prognosis.</jats:p
Determination of the Michel Parameters rho, xi, and delta in tau-Lepton Decays with tau --> rho nu Tags
Using the ARGUS detector at the storage ring DORIS II, we have
measured the Michel parameters , , and for
decays in -pair events produced at
center of mass energies in the region of the resonances. Using
as spin analyzing tags, we find , , , , and . In addition, we report
the combined ARGUS results on , , and using this work
und previous measurements.Comment: 10 pages, well formatted postscript can be found at
http://pktw06.phy.tu-dresden.de/iktp/pub/desy97-194.p
Theoretical Study of the \gamma\gamma-->meson-meson Reaction
We present a unified picture which studies simultaneously the gamma
gamma-->pi^+ pi^-, pi^0 pi^0, K^+ K^-, K^0 bar{K}^0, pi^0 eta reactions up to
about sqrt(s)=1.4 GeV reproducing the experimental cross sections. The present
work implements in an accurate way the final state interactions of the
meson-meson system, which is shown to be essential in order to reproduce the
data, particularly the L=0 channel. This latter channel is treated here
following a recent theoretical work in which the meson-meson amplitudes are
well reproduced and the f_0, a_0, sigma resonances show up clearly as poles of
the t matrix. The present work, as done in earlier ones, also incorporates
elements of chiral symmetry and exchange of vector and axial resonances in the
crossed channels, as well as a direct coupling to the f_2(1270) and a_2(1320)
resonances. We also evaluate the decay width of the f_0(980) and a_0(980)
resonances into the gamma-gamma channel.Comment: 20 pages, 13 figures, LaTeX. Only significant change in the
calculation of \gamma\gamma-->pi^+ pi^- from the more careful treatment of
the tail of the f_2(1270) resonanc
Photoproduction of the f2(1270) resonance
We have performed a calculation of the γp→π+π−p reaction, where the two pions have been separated in D-wave producing the f2(1270) resonance. We use elements of the local hidden gauge approach that provides the interaction of vector mesons in which the f2(1270) resonance appears as a ρ-ρ molecular state in L=0 and spin 2. The vector meson dominance, incorporated in the local hidden gauge approach converts a photon into a ρ0 meson and the other meson connects the photon with the proton. The picture is simple and has no free parameters, since the parameters of the theory have been constrained in the previous study of the vector-vector states. In a second step we introduce new elements, not present in the local hidden gauge approach, adapting the ρ propagator to Regge phenomenology and introducing the ρNN tensor coupling. We find that both the differential cross section as well as the t dependence of the cross section are in good agreement with the experimental results and provide support for the molecular picture of the f2(1270) in the first baryonic reaction where it has been tested
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