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ABSTRACT This article describes an analysis of recent change in both per capita earnings from employment and per capita income (including that from transfers and nonearnings sources) across New England's counties between 1970 and 2000. Breaking the period into three decade‐long spans (1970–1980, 1980–1990, and 1990–2000), statistical evidence is strong that the region experienced absolute divergence in both earnings and income. However, further statistical analysis that incorporates cost of living, human capital, and other control factors indicates that conditional convergence at the county scale in New England was ongoing rapidly between 1970 and 1990 and appears to have been achieved by 2000. 相似文献
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WAKA H. BLAIR JONATHAN M. LEVINE SHARON C. KERWIN KATHY A. SPAULDING BENJAMIN D. YOUNG ROY R. POOL 《Veterinary radiology & ultrasound》2011,52(3):309-312
Magnetic resonance (MR) imaging and histopathology were used to diagnose an articular process synovial myxoma in a dog. On MR images, the tumor was characterized by distortion of the left L1–L2 articular process, widening of the articular process joint, and the presence of a mass contiguous with the synovium of the articular process that displaced the spinal cord. The tumor was T2‐hyperintense, T1‐hypointense, relative to muscle, and had mild contrast enhancement. The MR features of articular process synovial myxoma may be distinct from other diseases of the articular process joint. 相似文献
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BENJAMIN SPALL ANNIE V. CHEN RUSSELL L. TUCKER KEVIN K. LAHMERS DANIEL J. RIGHTER JONATHAN HAYLES 《Veterinary radiology & ultrasound》2011,52(5):534-537
A 10‐year‐old Akita mix became acutely paraplegic. Upon magnetic resonance imaging, multiple, slightly T2‐hyperintense, T1‐isointense extradural masses, relative to spinal cord were found in the vertebral canal. The retroperitoneal masses had mixed T2‐signal intensity. The contrast enhancement pattern for the spinal masses was both homogenous and heterogenous. The diagnosis was metastatic pheochromocytoma. Signal intensity of the tumors in this dog was similar to reports of pheochromocytoma in human beings. 相似文献
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THOMAS P. HURST DANIEL W. COOPER JOEL S. SCHEINGROSS ERIN M. SEALE BENJAMIN J. LAUREL MARA L. SPENCER 《Fisheries Oceanography》2009,18(5):301-311
The role of behavior, especially vertical migration, is recognized as a critical component of realistic models of larval fish dispersion. Unfortunately, our understanding of these behaviors lags well behind our ability to construct three-dimensional flow-field models. Previous field studies of vertical behavior of larval Pacific cod ( Gadus macrocephalus ) were limited to small, preflexion stages (≤11 mm SL) in a narrow range of thermal conditions. To develop a more complete picture of larval behavior, we examined the effects of ontogeny, temperature, and light on vertical responses of larval Pacific cod in experimental columns. While eggs were strictly demersal, yolk-sac larvae displayed a strong surface orientation as early as 1 day post hatch (∼ 5 mm SL). Consistent with field observations, small preflexion larvae (<10 mm SL) showed no response to varying light levels. However, there was a direct effect of temperature on larval behavior: Pacific cod larvae exhibited a stronger surface orientation at 4°C than at 8°C. The behavior of larger, postflexion larvae (>15 mm SL) in experimental columns was consistent with a diel vertical migration and independent of water temperature: fish were more widely distributed in the column, and median positions were consistently deeper at higher light levels. These laboratory observations are combined with observations from discrete-depth (MOCNESS) sampling in the Gulf of Alaska to characterize the vertical distribution of larval Pacific cod and contrast ontogenetic patterns with walleye pollock ( Theragra chalcogramma ). The vertical movements of larval Pacific cod described here will be applied in the development of dispersal projections from Gulf of Alaska spawning grounds. 相似文献
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Objectives— To report rib fracture repair in a neonatal calf using the Securos® Cranial Cruciate Ligament Repair System (SCCLRS).
Study Design— Case report.
Animals— A 2-day-old female Holstein calf with fracture of right ribs 4–10.
Methods— On the day of admission the calf was anesthetized and rib fractures were repaired using open reduction and the SCCLRS.
Results— Rib fractures were successfully stabilized and the calf discharged from the hospital 8 days postoperatively.
Conclusions— Modification of previously reported use of the SCCLRS to repair rib fractures in foals was required because of the different anatomy in the calf. This new technique was rapidly and easily performed for a large number of fractured ribs in this case.
Clinical Relevance— Effective rib fracture repair in calves can be readily performed using the SCCLRS with modification of the technique reported in foals. 相似文献
Study Design— Case report.
Animals— A 2-day-old female Holstein calf with fracture of right ribs 4–10.
Methods— On the day of admission the calf was anesthetized and rib fractures were repaired using open reduction and the SCCLRS.
Results— Rib fractures were successfully stabilized and the calf discharged from the hospital 8 days postoperatively.
Conclusions— Modification of previously reported use of the SCCLRS to repair rib fractures in foals was required because of the different anatomy in the calf. This new technique was rapidly and easily performed for a large number of fractured ribs in this case.
Clinical Relevance— Effective rib fracture repair in calves can be readily performed using the SCCLRS with modification of the technique reported in foals. 相似文献
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ABSTRACT Over the past twenty years, the environmental regulation of landfills has become increasingly restrictive both at the federal and state levels. Using a panel dataset of Ohio landfills, we developed a theoretical framework to explain the landfill operators’ responses to regulatory actions, and then estimate an empirical model of changes in industry structure. Because not all Ohio counties have landfill operations, we hypothesize that there is self‐selection in the location of landfills, which is accounted for with an appropriate econometric model. The study finds that environmental regulations had significant impact both on the location of landfill operations and concentration of the industry during the time period studied. 相似文献
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生物炭碳固定于稳定性土壤团聚体中：土壤黏土矿物及其它土壤性质的作用 总被引：2，自引：0，他引：2
Charlene N. KELLY Joseph BENJAMIN Francisco C. CALDERÓN Maysoon M. MIKHA David W. RUTHERFORD Colleen E. ROSTAD 《土壤圈》2017,27(4):694-704
Aggregation and structure play key roles in water-holding capacity and stability of soils.In this study,the incorporation of carbon(C) from switchgrass biochar into stable aggregate size fractions was assessed in an Aridisol(from Colorado,USA) dominated by 2:1 clays and an Alfisol(from Virginia,USA) containing weathered mixed 1:1 and 2:1 mineralogy,to evaluate the effect of biochar addition on soil characteristics.The biochar was applied at 4 levels,0,25,50,and 100 g kg~(-1),to the soils grown with wheat in a growth chamber experiment.The changes in soil strength and water-holding capacity using water release curves were measured.In the Colorado soil,the proportion of soil occurring in large aggregates decreased,with concomitant increases in small size fractions.No changes in aggregate size fractions occurred in the Virginia soil.In the Colorado soil,C content increased from 3.3 to 16.8 g kg~(-1),whereas in the53 μm fraction C content increased from 5.7 to 22.6 g kg~(-1) with 100 g kg~(-1)biochar addition.In the Virginia soil,C content within aggregate size fractions increased for each size fraction,except the2 000 μm fraction.The greatest increase(from 6.2 to 22.0 g kg~(-1)) occurred in the 53–250 μm fraction.The results indicated that C was incorporated into larger aggregates in the Virginia soil,but remained largely unassociated to soil particles in the Colorado soil.Biochar addition had no significant effect on water-holding capacity or strength measurements.Adding biochar to more weathered soils with high native soil organic content may result in greater stabilization of incorporated C and result in less loss because of erosion and transport,compared with the soils dominated by 2:1 clays and low native soil organic content. 相似文献