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ABSTRACT Despite the fact that nonemployment income makes up approximately one-third of all personal income, its impact on local area economies has not been closely examined. This study uses Michigan county data to examine the impact of nonemployment income on nonbasic income over a twenty-seven-year period. This impact is compared to the impact of basic income by employing regression analysis to estimate comparative multiplier effects for both types of income. Nonemployment income is found to have a significant impact on nonbasic income, particularly in metropolitan and nonmetropolitan urban counties, where its impact appears to be stronger than that of basic income.  相似文献   
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The surface potential of biological membranes varies according to their lipid composition. We devised genetically encoded probes to assess surface potential in intact cells. These probes revealed marked, localized alterations in the charge of the inner surface of the plasma membrane of macrophages during the course of phagocytosis. Hydrolysis of phosphoinositides and displacement of phosphatidylserine accounted for the change in surface potential at the phagosomal cup. Signaling molecules such as K-Ras, Rac1, and c-Src that are targeted to the membrane by electrostatic interactions were rapidly released from membrane subdomains where the surface charge was altered by lipid remodeling during phagocytosis.  相似文献   
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Laser-cooled 9Be+ ions confined in two-dimensionally extended lattice planes were directly observed, and the images were used to characterize the structural phases of the ions. Five different stable crystalline phases were observed, and the energetically favored structure could be sensitively tuned by changing the areal density of the confined ions. The experimental results are in good agreement with theoretical predictions for the planar (infinite in two dimensions) one-component plasma. Qualitatively similar structural phase transitions occur, or are predicted to occur, in other experimentally realizable planar systems.  相似文献   
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The effects of feeding rates on growth, feed conversion, protein deposition and carcass quality of fingerling Catla catla (3.61 ± 0.03 cm; 0.71 ± 0.04 g) were worked out by conducting a 16‐week feeding trial. Fingerlings were fed with a casein‐gelatin‐based purified diet (40% crude protein CP; 14.95 MJ kg?1 digestible energy; DE) at 1%, 2%, 3%, 4%, 5%, 6% and 7% body weight per day. The absolute weight gain (AWG; 10.50 g fish?1) and feed conversion ratio (FCR; 1.41) were highest at the feeding rate of 5% body weight per day. However, protein gain (PG; 0.36 g fish?1) and carcass protein content attained the maximum values at 4% BW day?1. Quadratic regression analyses of AWG g fish?1 and PG g fish?1 at 95% maximum response indicated that these parameters attained the best values at 4.19% and 3.81% BW day?1. On the basis of the above results it is recommended that the feeding rate in the range of 3.81–4.19% BW day?1 with a P:E ratio of 26.69–27.74 mg protein MJ?1 DE is optimum for maximum growth, efficient feed conversion and best carcass quality in fingerling C. catla.  相似文献   
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This study was aimed at quantifying methionine requirement of Indian major carp fry, Cirrhinus mrigala (2.2 ± 0.2 cm; 0.19 ± 0.02 g) by conducting a 12‐week feeding trial. Casein–gelatine‐based isonitrogenous (40 g 100 g?1 crude protein) and isoenergetic (15.42 kJ g?1 DE) amino acid test diets were prepared to contain six levels of l ‐methionine (1.1, 1.3, 1.5, 1.7, 1.9 and 2.1 g 100 g?1 dry diet) at a fixed level of cysteine (0.85 g 100 g?1 dry diet) and fed to apparent satiation thrice daily to triplicate groups of fish. When absolute weight gain (g per fish), feed conversion ratio, protein deposition (g per fish) and nitrogen retention efficiency data were subjected to broken‐line and second‐degree polynomial regression analysis, 95% of the plateau of above parameters was achieved at dietary methionine concentrations between 1.60 and 1.69 g 100 g?1 dry diet or 0.10 to 0.11 g methionine kJ?1 DE, corresponding to 4.1–4.22 g 100 g?1 protein or 0.44–0.47 g methionine kJ?1 DE. Based on these results, dietary methionine requirement of fry C. mrigala is recommended 1.60–1.69 g 100 g?1 diet or 0.10–0.11 g methionine kJ?1 DE.  相似文献   
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Connexin43 (Cx43) is a major protein of myometrial gap junctions. The number of Cx43 gap junctions increase dramatically with the onset of labour in association with development of synchronized uterine contractions. The formation of myometrial gap junctions follows an increase in the oestrogen to progesterone ratio indicating an important role of steroid hormones in regulating Cx43 expression at term. However, no relationship has been established between the expression of Cx43 in the non‐pregnant myometrium and concentration of steroid hormones during the oestrous cycle. Here, we used immunofluorescence and Western blotting to analyse the expression of Cx43 gap junctions in the myometrium of pre‐pubertal pigs (n = 7) and mature pigs at pre‐ovulatory (n = 7), luteal (n = 5) and late luteal (n = 3) stages of the oestrous cycle. The number of Cx43 gap junctions calculated per 1 mm2 of the myometrial section was low in pre‐pubertal pigs and significantly higher (p < 0.022) in pre‐ovulatory animals. In relation to pre‐ovulatory animals the number of myometrial gap junctions was significantly lower (p < 0.019) at the luteal phase and correlated with significantly higher (p < 0.005) concentration of endogenous progesterone. Phosphorylated isoforms of Cx43 protein were expressed in the myometrium of pre‐pubertal pigs and mature animals at pre‐ovulatory and late luteal phases, while they were down regulated at the luteal stage. These results indicate that changes of Cx43 expression in the porcine myometrium during the oestrous cycle may be regulated by progesterone concentration and may contribute to the modulation of uterine motility.  相似文献   
8.
Squamous metaplasia of the oviduct epithelium is a rare disorder of reproductive organs. We noted squamous metaplasia of the oviduct epithelium in a sow routinely slaughtered at day 2 of the oestrous cycle. Expression of transforming growth factor beta3 (TGF beta3) in the metaplastic epithelia was evaluated by immunohistochemistry, because TGF beta3 appears to play a key role as regulator of a variety of tissue remodelling events. Our results show that TGF beta3 immunostaining was specifically localized to foci of squamous metaplasia of the epithelial linings. Non‐metaplastic epithelial cells of the oviduct were not immunostained with anti‐TGF beta3 antibody. At the subcellular level, TGF beta3‐labelled cells occasionally showed signs of apoptotic cell death. It is concluded that signals produced by TGF beta3 in metaplastic lesions of the oviduct are potentially involved in pathophysiological processes.  相似文献   
9.
The present study was carried out to identify the excretory/secretory (E/S) antigens of the rumen infecting digenetic trematode Gastrothylax crumenifer that may be useful for the immunodiagnosis of rumen amphistomosis particularly during the pre-monsoon season during which this rumen parasite stops shedding eggs. The in vitro released E/S proteins were purified on a Sephadex G-200 column. The gel filtration profile revealed three distinct fractions F1-F3 where F1 and F3 appeared as sharp peaks while the F2 fraction was dispersed. The antibody titre against each of the purified E/S fractions was determined by ELISA using anti-whole E/S polyclonal antibodies raised in rabbit. Among the three fractions, the antibody titre against F1 was highest (1:12,800) whereas IgG titre was very low (1:50) for fraction F2 and F3 (1:100). Of the total polypeptides resolved on gradient SDS-PAGE, only a few antigenic polypeptides were detected in each fraction with hyperimmune anti-serum as revealed by Western Blot analysis. However, a 33 kDa antigen detected in each fraction appeared to be immunodominant which could be exploited for the diagnosis of the pouched amphistome.  相似文献   
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