138 research outputs found
Chemical Tracing Techniques for Evaluating Rill Hydraulics
Development of water erοsiοn and surface water quality control practices requires information concerning the hydraulic characteristics of upland areas. The relatively small flow rates normally found within rills make measurement of hydraulic parameters difficult. Chemical tracing procedures, originally developed for stream and river systems, have been successfully used to measure rill flow properties. A chemical tracer of known concentration is added to the rill and by knowing the degree of dilutiοn at a downstream sampling point, flow rate can be calculated. Rill flow velocity can be measured by determining the time required for a slug of tracer material to travel a designated distance. Measurements of flow rate and velοcity can be used tο calculate οther hydraulic variables. The ability to understand and properly mοdel rill flοw will improve as additional information [is gathered]
On elliptic factors in real endoscopic transfer I
This paper is concerned with the structure of packets of representations and
some refinements that are helpful in endoscopic transfer for real groups. It
includes results on the structure and transfer of packets of limits of discrete
series representations. It also reinterprets the Adams-Johnson transfer of
certain nontempered representations via spectral analogues of the
Langlands-Shelstad factors, thereby providing structure and transfer compatible
with the associated transfer of orbital integrals. The results come from two
simple tools introduced here. The first concerns a family of splittings of the
algebraic group G under consideration; such a splitting is based on a
fundamental maximal torus of G rather than a maximally split maximal torus. The
second concerns a family of Levi groups attached to the dual data of a
Langlands or an Arthur parameter for the group G. The introduced splittings
provide explicit realizations of these Levi groups. The tools also apply to
maps on stable conjugacy classes associated with the transfer of orbital
integrals. In particular, they allow for a simpler version of the definitions
of Kottwitz-Shelstad for twisted endoscopic transfer in certain critical cases.
The paper prepares for spectral factors in twisted endoscopic transfer that are
compatible in a certain sense with the standard factors discussed here. This
compatibility is needed for Arthur's global theory. The twisted factors
themselves will be defined in a separate paper.Comment: 48 pages, to appear in Progress in Mathematics, Volume 312,
Birkha\"user. Also renumbering to match that of submitted versio
Hydraulic Characteristics of Rills
Rill density and rill flow rates were determined during rainfall simulation tests conducted at 11 sites located throughout the eastern United States. A mean rill density of 1.0 rills/m was found for the study locations. From measurements of the relative distribution of flow rates, a procedure is identified for partitioning flow between individual rills.
Regression equations were developed for relating rill width and hydraulic roughness coefficients to flow rate. Equations were also derived for predicting mean flow velocity from visually determined measurements of advance velocity. Information reported in this study can be used to estimate hydraulic characteristics of rills
Hydraulic Conditions Required to Move Unanchored Residue Materials
Hydraulic conditions required to initiate movement of unanchored residue materials are identified in the present study. Selected amounts of corn, cotton, pine needles, sorghum, soybean, sunflower, and wheat residue are placed in a flume on a sand surface, and flow is then introduced at the top of the flume in progressive increments. The discharge rate and flow velocity necessary to cause residue movement are determined. The ratio of critical flow depth to residue diameter, critical Reynolds number, critical shear stress, dimensionless shear stress, and boundary Reynolds number are calculated from hydraulic measurements. Regression equations are developed to relate dimensionless shear stress to boundary Reynolds number and residue diameter. Boundary Reynolds number, in turn, is related to residue diameter and cover. Close agreement is found between predicted and actual parameter values obtained from the regression relations. The regression equations can be used to estimate the beginning of motion for other residue materials if residue diameter and cover are known
On a Conjecture of Rapoport and Zink
In their book Rapoport and Zink constructed rigid analytic period spaces
for Fontaine's filtered isocrystals, and period morphisms from PEL
moduli spaces of -divisible groups to some of these period spaces. They
conjectured the existence of an \'etale bijective morphism of
rigid analytic spaces and of a universal local system of -vector spaces on
. For Hodge-Tate weights and we construct in this article an
intrinsic Berkovich open subspace of and the universal local
system on . We conjecture that the rigid-analytic space associated with
is the maximal possible , and that is connected. We give
evidence for these conjectures and we show that for those period spaces
possessing PEL period morphisms, equals the image of the period morphism.
Then our local system is the rational Tate module of the universal
-divisible group and enjoys additional functoriality properties. We show
that only in exceptional cases equals all of and when the
Shimura group is we determine all these cases.Comment: v2: 48 pages; many new results added, v3: final version that will
appear in Inventiones Mathematica
A Prospective Pilot Study to Identify a Myocarditis Cohort who may Safely Resume Sports Activities 3Â Months after Diagnosis
International cardiovascular society recommendations to return to sports activities following acute myocarditis are based on expert consensus in the absence of prospective studies. We prospectively enrolled 30 patients with newly diagnosed myocarditis based on clinical parameters, laboratory measurements and cardiac magnetic resonance imaging with mildly reduced or pre served left ventricular ejection fraction (LVEF) with a follow-up of 12 months. Cessation of physical activity was recommended for 3 months. The average age was 35 (19–80) years with 73% male patients. One case of non-sustained ventricular tachycardia was recorded during 48-h-Holter electrocardiogram. Except for this case, all patients were allowed to resume physical exercise after 3 months. At 6- (n = 26) and 12-month (n = 19) follow-up neither cardiac events nor worsening LVEF were recorded. The
risk of cardiac events at 1 year after diagnosis of myocarditis appears to be low after resumption of exercise after 3 months among patients who recover from acute myocarditis
Myoglobin for Detection of High-Risk Patients with Acute Myocarditis
There is an unmet need for accurate and practical screening to detect myocarditis. We sought to test the hypothesis that the extent of acute myocarditis, measured by late gadolinium enhancement (LGE) on cardiac magnetic resonance imaging (CMR), can be estimated based on routine blood markers. A total of 44 patients were diagnosed with acute myocarditis and included in this study. There was strong correlation between myoglobin and LGE (rs = 0.73 [95% CI 0.51; 0.87], p < 0.001), while correlation was weak between LGE and TnT-hs (rs = 0.37 [95% CI 0.09; 0.61], p = 0.01). Receiver operating curve (ROC) analysis determined myoglobin ≥ 87 μg/L as cutoff to identify myocarditis (92% sensitivity, 80% specificity). The data were reproduced in an established model of coxsackievirus B3 myocarditis in mice (n = 26). These data suggest that myoglobin is an accurate marker of acute myocarditis. Graphical Abstract Receiver operating curve analysis determined myoglobin ≥ 87 μg/L as cutoff to identify myocarditis and these data were reproduced in an established model of coxsackievirus B3 myocarditis in mice: CMRI, cardiac magnetic resonance imaging; Mb, myoglobin; LGE, late gadolinium enhancement; ROC, receiver operating curve analysis
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