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71.
During summer 1982, responses of lactating Holstein and Guernsey cows were measured by milk temperature recorded by a Digital Dataloger with thermocouples attached to Boumatic flow meters. Maximum air temperature and temperature-humidity index averaged 30.8 degrees C and 75.6 for July. Breed did not affect milk temperature, but within-breed milk temperature increased with production. In a second study, benefits of spray cooling were evaluated with 24 Holsteins in midlactation assigned randomly to two groups of 12 and maintained under loose-housing conditions. Spray nozzles were installed in the walkways and under the manger shade for the spray treatment group. Maximum temperature and temperature-humidity index during the spray study were 27 degrees C and 73.9. Rectal temperature taken following milking averaged less for treatment than control (38.8 versus 39.1 degrees C). Milk temperature was similar (37.8 versus 38.1 degrees C). Daily milk yield was .70 kg higher than controls. Milk temperature may provide reliable indication of climate stress similar to rectal temperature, and spray cooling improves cow comfort and lessens summer decline of milk production. 相似文献
72.
Ronald Y. S. Pak Feng Ji 《International journal for numerical methods in engineering》1994,37(14):2501-2520
A boundary integral equation method is presented for the analysis of a thin cylindrical shell embedded in an elastic half-space under axisymmetric excitations. By virtue of a set of ring-load Green's functions for the shell and a group of dynamic fundamental solutions for the semi-infinite medium, the structure–medium interaction problem of wave propagation is shown to be reducible to a set of coupled boundary integral equations. Through the analysis of an auxiliary pair of Cauchy integral equations, the singularities of the contact stress distributions arc rendered explicit. With a direct incorporation of such analytical features into the formulation, an effective computational procedure is developed which involves an interpolation of regular functions only. Typical results for the dynamic contact load distributions, displacements, and complex compliance functions are included as illustrations. In addition to furnishing quantities of direct engineering interest, this treatment is apt to be useful as a foundation for further rigorous as well as approximate developments for various related physical problems and boundary integral methods. 相似文献
73.
RA Reinhardt MP Masada GK Johnson LM DuBois GJ Seymour AC Allison 《Canadian Metallurgical Quarterly》1993,20(7):514-519
Interleukin (IL)-1 alpha and beta are cytokines which can mediate inflammatory, bone resorbing, and reparative effects in the periodontium, but few longitudinal data exist exploring their role following periodontal therapy. This study examined gingival crevicular fluid (GCF) concentrations of IL-1 alpha and IL-1 beta at sites with shallow sulci (SS) or inflamed moderate/advanced pockets (M/AP) before and 6 months after treatment with closed scaling/root planing (SC/RP) or papillary flap debridement (PFD), all in the same subject (n = 14 patients). No significant differences were noted in IL-1 alpha or beta concentrations (determined with two-site enzyme-linked immunosorbent assays) between SS and M/AP sites at baseline. While both therapies improved clinical parameters of periodontal disease, IL-1 alpha concentration increased significantly (p < 0.05) in M/AP-PFD sites 6 months after treatment, but were unchanged in other groups. IL-1 beta concentrations were numerically lower after therapy, except for a significant increase (p < 0.05) in M/AP-PFD sites. These data suggest that surgical wound healing in an inflamed, plaque-infected site (M/AP-PFD) results in prolonged production of IL-1, which may be a reflection of the extent of tissue trauma and delayed wound healing. In spite of increased IL-1 levels, these sites demonstrated significant short-term improvement in clinical attachment level (+ 1.8 mm, p < or = 0.001) postoperatively. 相似文献
74.
MM Berenson TD Johnson NR Markowitz KN Buchi WS Samowitz 《Canadian Metallurgical Quarterly》1993,104(6):1686-1691
BACKGROUND: Antireflux therapy has generally failed to induce regression of Barrett's epithelium. It was hypothesized that squamous epithelium could be restored if the columnar tissue was ablated while gastric acid secretion was suppressed. METHODS: Ten white men with Barrett's esophagus received 40 mg of omeprazole daily. Thereafter, every 2-5 weeks they underwent videotaped endoscopies to argon laser photoablate columnar tissue, obtain biopsy specimens, and assess results. Squamous re-epithelialization was assessed by correlation of videotapes and directed biopsies. RESULTS: Patients had one to eight areas ablated, totaling 0.5-12.0 cm2. Videotape assessments were corroborated by biopsy in all but one instance. Thirty-eight of 40 treatment locations partially or completely re-epithelialized with squamous tissue. Squamous regrowth appeared to occur by spread from contiguous squamous borders and de novo from glandular tissue. Regrowth was influenced by the extent of squamous borders and completeness of ablations. Nonablated glandular tissue persisted beneath squamous epithelium. CONCLUSIONS: Ablation of Barrett's epithelium and suppression of acid secretion facilitated squamous re-epithelialization. A progenitor cell within the metaplastic tissue has the potential to differentiate normally. 相似文献
75.
76.
Constructions of particular random processes 总被引:1,自引:0,他引:1
Johnson G.E. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1994,82(2):270-285
This paper reviews how to construct sets of random numbers with particular amplitude distributions and correlations among values. These constructions support both high-fidelity Monte Carlo simulation and analytic design studies. A variety of constructions is presented to free engineering models from “white or normal” limitations embodied in many current simulations. The methods support constructions of conventional stationary and normally distributed processes, nonstationary, nonnormal signal and interference waveforms, nonhomogeneous random scenes, nonhomogeneous volumetric clutter realizations, and snapshots of randomly evolving, nonhomogeneous scenes. Each case will have specified amplitude statistics, e.g., normal, log-normal, uniform, Weibull, or discrete amplitude statistics; and selected correlation, e.g., white, pink, or patchy statistics, clouds. or speckles. Sets of random numbers with correlation, nonstationarities, various tails for the amplitude distributions, and multimodal distributions can be constructed. The paper emphasizes aspects of probability theory necessary to engineering modeling 相似文献
77.
78.
Osteopontin in chronic puromycin aminonucleoside nephrosis 总被引:1,自引:0,他引:1
Increased expression of osteopontin (OPN) associated with interstitial monocyte infiltration has been demonstrated in the early phase of a variety of experimental renal diseases. Whether these changes occur in the chronic phase of progressive glomerular disease is unknown. Chronic puromycin aminonucleoside nephrosis (PAN) was induced in 16 rats by the injection of a single bolus of PA into the internal jugular vein, which results in a triphasic disease characterized by minimal glomerular change and marked proteinuria, peaking at about 10 to 14 d and subsiding by 28 d, followed by a quiescent 4-wk period of no or minimal proteinuria and then the development of progressive focal glomerulosclerosis (FGS) and increasing proteinuria. Fifteen rats injected similarly with normal saline served as controls. At 11 d after injection, PA rats demonstrated significantly greater urinary protein excretion (P = 0.0107), cortical tubular OPN expression (P = 0.0086), and intraglomerular (P = 0.0009) and interstitial (P = 0.0212) monocyte infiltration than did the controls. At 42 d, no significant differences between the two groups with respect to the above parameters were detected. At 98 d, PA rats had FGS and showed a definite trend to increased proteinuria, cortical tubular OPN, and intraglomerular monocyte infiltration. Although the cortical interstitial monocyte count was not elevated in PA rats compared with controls, there were significantly more monocytes around OPN-positive cortical tubules than around OPN-negative ones (P = 0.0011). Cortical tubular OPN expression correlated well with urinary protein excretion (r = 0.932, P < 0.0001), cortical tubular proliferating cell nuclear antigen (r = 0.796, P < 0.0001), and intraglomerular monocyte count (r = 0.552, P = 0.0013). The results are consistent with a monocyte chemoattractant role for OPN and suggest that OPN is upregulated in the chronic phase of PAN and that this increase in expression is a result of glomerular events. 相似文献
79.
When planning an SDH network, explicit structure, such as rings or a network hierarchy, is often imposed to allow for easier network protection and management. Decisions on node connectivity are also heavily dependent on available transmission capacity and network geography, as well as the demands placed on the SDH transport layer. The strictly imposed structure therefore makes it unlikely for unplanned properties to appear but here we describe how the BT SDH network exhibits emergent power-law properties in a range of metrics. These properties are similar to those previously found in the Internet, but the Internet in contrast is not globally planned, has adaptive elements such as dynamic routing and peering agreements, lacks explicit imposed structure, and is less coupled to transmission topologies.This paper shows that even with a wide range of restrictions and controls the BT SDH network topology follows power-laws and we offer possible sources for them, concentrating on the possible effect of adjacent network layers. The existence of these properties has wide implications in network modelling, as well as network scaling, growth, and robustness analysis. 相似文献
80.
T. Jacob and K. Leonard (1986) reported that children of alcoholic fathers were comparable to children of depressed fathers in their psychosocial functioning. These results, however, were based on a relatively homogeneous sample. In the current study, previous results were extended by examining a sample of alcoholic fathers who were not screened for additional paternal psychiatric disorders or for major maternal psychopathology. Children in the unscreened and screened samples could not be distinguished in their functioning, and the majority of children of alcoholic fathers were functioning in the normal range of the Child Behavior Checklist. Given the heterogeneous adjustment in children of alcoholic fathers, the authors examined a range of factors that might protect against or exacerbate the risk associated with paternal alcoholism. Maternal depression and certain demographic characteristics were associated with poorer child functioning, particularly for male children. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献