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1.
Enthusiasm for using beaver dam analogues (BDAs) to restore incised channels and riparian corridors has been increasing. BDAs are expected to create a similar channel response to natural beaver dams by causing channel bed aggradation and overbank flow, which subsequently raise water tables and support vegetation growth. However, lack of funding for monitoring projects post‐restoration has limited research on whether BDAs actually cause expected channel change in the Front Range and elsewhere. Geomorphic and hydrologic response to BDAs was monitored in two watersheds 1 year post‐restoration. BDAs were studied at Fish Creek, a steep mountainous catchment, and Campbell Creek, a lower gradient piedmont catchment from May to October 2018. At each restoration site, the upstream‐ and downstream‐most BDAs were chosen for intensive study in comparison with unrestored reference reaches. Monitoring focused on quantifying sediment volumes in BDA ponds and recording changes to stream stage and riparian groundwater. Despite differences in physical basin characteristics, BDA pools at both sites stored similar volumes of sediment and stored more sediment than reference pools. Sediment storage is positively correlated to BDA height and pool surface area. However, BDAs did not have a significant influence on shallow groundwater. The lack of groundwater response proximal to BDAs could indicate that local watershed factors have a stronger influence on groundwater response than restoration design 1 year post‐restoration. Systematic, long‐term studies of channel and floodplain response to BDAs are needed to better understand how BDAs will influence geomorphology and hydrology.  相似文献   
2.
A comparison was made of the esterase and activator activities of the various activated forms of human plasminogen and their streptokinase complexes with Nalpha-Cbz-L-lysine-p-nitrophenyl ester as the substrate. The steady state kinetic properties of Glu- and Lys-plasmins, and Glu- and Lys-plasminogen-streptokinase complexes were identical, while the Lys-plasmin-streptokinase complex showed a 2-fold increase in Km with the same kcat and a 3-fold increase in Ki for the competitive inhibitor leupeptin. Lys-plasminogen (zymogen with an active site) was prepared which incorporated 0.7 mol of [3H]idisopropyl phosphorofluoridate and 0.43 mol of p-nitrophenyl-p'-guanidinobenzoate/mol of protein. The Km for Lys-plasminogen was 3-fold higher than that of Lys-plasmin, and its maximum velocity 10-fold lower. The steady state kinetic parameters of a plasmin-derived light (B) chain (CmCys)3, and a derived equimolar light (B) chain-streptokinase complex (CmCys)3, isolated from human plasmin and equimolar plasmin-streptokinase, or plasminogen-streptokinase, complexes, respectively, were determined. When the light (B) chain-streptokinase complex is isolated from its parent complexes, there is a complete retention of the original parent's esterase activities, with respect to Km and kcat, and interaction with the competitive inhibitors benzamidine and leupeptin. The plasmin-derived light (B) chain does not retain its parent esterase activities. This chain has very similar kinetic properties to Lys-plasminogen except that streptokinase, in an equal molar amount, does not impart full esterase activity to the light (B) chain whereas the zymogen can be completely activated by streptokinase. The kcat of the plasmin-derived light (B) chain, and its streptokinase complex can be enhanced by 50 and 30%, respectively, in the presence of 10(-4) M leupeptin, a competitive inhibitor of plasmin, attesting to the increased structural flexibility within the active site of this enzyme species. Urokinase hydrolyzes Nalpha-Cbz-L-lysine p-nitrophenyl ester efficiently with a kcat/Km of one-third that of plasmin. The human plasminogen activator activities of various activated forms of human plasminogen and their equimolar streptokinase complexes were compared in a kinetic assay. The Lys-plasmin-streptokinase complex, and streptokinase were the least active of the activator species and were approximately equal in their activator activities. Glu- and Lys-plasminogen-streptokinase complexes had approximately 1.5 times the activity of streptokinase, whereas the equimolar light (B) chain-streptokinase complexes had approximately 2- to 3-times the activator activity of streptokinase. Since the esterase activity remained unchanged, this indicates a greater degree of specificity in the active site of the equimolar light (B) chain-streptokinase activator complex. Urokinase proved to be a poor activator species...  相似文献   
3.
Neuropsychological evaluation of 73 older healthy, unmedicated outpatients with major depression and 110 controls suggested that relatively distinct cognitive profiles may correspond to the presence vs. severity of depression. Specifically, the presence of depression was associated with subtle weaknesses in visual memory and nonverbal intelligence, with sparing of verbal skills (verbal intelligence, language, and verbal memory), constructional ability, attention, information processing speed, and executive functions. In contrast, increasing severity of depression was associated with mild weaknesses, primarily in information-processing speed and executive skills, but was essentially unrelated to memory (verbal or visual), intelligence, language skills, constructional ability, or basic attention. Findings are discussed in terms of a possible state vs. trait model of depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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5.
The objective of the paper is to draw attention to a rare cause of rapidly progressing renal failure which developed in the course of four months as a result of light chain deposition disease. The authors submit two case-histories of the disease assessed by renal biopsy after previous clinical and laboratory suspicion of monoclonal gammapathy. In one patient in the sternal punctate plasmacytoma was diagnosed and in the second case it was not possible to detect any type of monoclonal gammapathy or another possible cause of disease. Renal failure was in both cases irreversible and both patients were enlisted in regular haemodialyzation treatment.  相似文献   
6.
[Correction Notice: An erratum for this article was reported in Vol 23(4) of Psychology of Addictive Behaviors (see record 2009-24023-002). Some data in Table 4 was inadvertently omitted. The complete Table 4 is presented in the erratum.] Although craving is an important feature of problem gambling, there is a paucity of research investigating craving to gamble. A major stumbling block for craving research in gambling has been the lack of a methodologically sound, multidimensional measure of gambling-related craving. This article reports the development of the Gambling Craving Scale (GACS). In Study 1 (N = 220), a factor analysis revealed the emergence of a 9-item scale with 3 factors: Anticipation, Desire, and Relief. An important finding was that the GACS predicted problem gambling severity, depression, and positive and negative affect. In Study 2 (N = 145), the factor structure of the GACS was confirmed using a community sample of gamblers. In Study 3 (N = 46), GACS scores significantly predicted persistence at play on a virtual slot machine in the face of continued loss. Specifically, the more participants craved to gamble, the longer they engaged in play. The implications of craving for the development and maintenance of problem gambling severity are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
7.
A series of copoly(imide alkyl ether)s were synthesized to explore surface migration of fluorinated alkyl ether blocks (AEFO)s. Mechanical and surface properties of solution cast, thermally imidized films were determined. Incorporation of the AEFO oligomers at loading levels up to 5 wt % resulted in a slight decrease (usually less than 10%) in tensile modulus. Surface migration of the AEFOs raised the advancing water contact angle from approximately 80° to above 95° for the copolymer systems. The composition at which addition of more AEFO further increased water contact angle values was related to the number of fluorine atoms in the perfluorinated side chains. Surface excess concentration of the AEFO at different loading levels was calculated from X‐ray photoelectron spectroscopy results. At higher AEFO loading levels, the surface excess concentration was relatively constant suggesting formation of stable structures within the bulk similar to micelle formation in surfactant solutions. Based on these results, it was determined that surface saturation occurred with the fluorinated AEFO species at loading levels as low as 1 wt % engendering changes in surface properties while retaining the bulk imide properties. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41538.  相似文献   
8.
This personal note focuses on the market for PC word processing software and how it established a pattern of a popular product dominating the market until overtaken and pushed aside by its successor.  相似文献   
9.
To characterize the outcome of lobectomy in infancy and the low expiratory flows which persist after lobectomy for congenital lobar emphysema, 15 subjects with this history were studied at age 8-30 yr. Total lung capacity was normal in all, but higher values (P < 0.05) were observed in nine subjects with upper lobectomy than in five subjects with right middle lobectomy. Ratio of residual volume to total lung capacity was correlated (P < 0.05) with the amount of lung missing as estimated from normal relative weights of the respective lobes. Xe(133) radiospirometry in eight subjects showed that the operated and unoperated sides had nearly equal volumes at total lung capacity, but that the operated side was larger than the unoperated side at residual volume. Perfusion was equally distributed between the two sides. Similar findings were detected radiographically in four other subjects. Forced expiratory volume in 1 s and maximal midexpiratory flow rate averaged 72 and 45% of predicted, respectively. Low values of specific airway conductance and normal density dependence of maximal flows in 12 subjects suggested that obstruction was not limited to peripheral airways. Pathologic observations at the time of surgery and morphometry of the resected lobes were not correlated with any test of pulmonary function. These data show that lung volume can be completely recovered after lobectomy for congenital lobar emphysema in infancy. The volume increase occurs on the operated side, and probably represents tissue growth rather than simple distension. The response to resection is influenced by the particular lobe resected and may be associated with decreased lung recoil near residual volume. Low expiratory flows in these subjects could be explained by several mechanisms, among which a disproportion between airway and parenchymal growth in infancy (dysanaptic growth) is most compatible with our data.  相似文献   
10.
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