THE DETERMINANTS OF WAGE INCREASES IN NEW MANUFACTURING PLANTS IN RURAL AREAS

Labor and Human Capital,

The determinants of wage increases in new manufacturing plants in rural areas

The research reported here was designed to explain variation in wage changes of new industrial plant employees. Following the theoretical perspectives of Gotsch, wage changes were hypothesized to result from a combination of employee household, community, and plant characteristics. The greatest difficulty in this study was choosing appropriate operational measures for independent variables that were highly correlated with these theoretical factors.Southern journal of agricultural economics, July 1981, p. 84-88Includes bibliographical reference

Quantitative Measurement of PIT1, GH, and PRL mRNA and Circulating Hormone Levels in Pig Families Segregating PIT1 Genotypes

PIT1 is a member of the POU-domain family gene and is a positive regulator for growth hormone (GH), prolactin (PRL), and thyrotroph-stimulating hormone β(TSHB) in several mammalian species. Previous studies in pigs have shown an association of PIT1 polymorphisms with growth and carcass traits in which the primarily Chinese alleles were associated with heavier birth weight and greater backfat. To further investigate the role of PIT1 in controlling pig growth traits, Chinese Meishan (MS) pigs segregating PIT1 polymorphisms were used to study the differences of GH and PRL at both mRNA and circulating hormone levels. A total of 60 animals from nine litters was used to collect both pituitary and blood samples at day 1, 15, and 30 after birth. A novel procedure that involves standard curve quantification was used to quantify mRNA amount for GH, PRL, PIT1-α, and PIT1-β. Conventional hormone assays were done to measure the circulating amount of GH and PRL from the blood. Statistical analyses of PIT1 genotypes, sex, and days on either mRNA (PIT1 alternative transcripts, GH, and PRL) or circulating hormone (GH and PRL) were done by using the leastsquares procedure. This study investigates GH and PRL at both mRNA and circulating hormone levels in MS pigs segregating PIT1 polymorphisms. Results from this study will provide useful information on the role of PIT1 in controlling pig growth traits

How Are Red and Blue Quasars Different? The Radio Properties

A non-negligible fraction of quasars are red at optical wavelengths, indicating (in the majority of cases) that the accretion disc is obscured by a column of dust which extinguishes the shorter-wavelength blue emission. In this paper, we summarize recent work by our group, where we find fundamental differences in the radio properties of SDSS optically-selected red quasars. We also present new analyses, using a consistent color-selected quasar parent sample matched to four radio surveys (FIRST, VLA Stripe 82, VLA COSMOS 3 GHz, and LoTSS DR1) across a frequency range 144 MHz–3 GHz and four orders of magnitude in radio flux. We show that red quasars have enhanced small-scale radio emission (∼kpc) that peaks around the radio-quiet threshold (defined as the ratio of 1.4 GHz luminosity to 6 μm luminosity) across the four radio samples. Exploring the potential mechanisms behind this enhancement, we rule out star-formation and propose either small-scale synchrotron jets, frustrated jets, or dusty winds interacting with the interstellar medium; the latter two scenarios would provide a more direct connection between opacity (dust; gas) and the production of the radio emission. In our future study, using new multi-band uGMRT data, we aim to robustly distinguish between these scenarios

Comparative Ovarian and Pituitary Hormone Secretion in Pregnant Meishan and Yorkshire Gilts

Chinese Meishan and Yorkshire were used to investigate mechanisms regulating the production and secretion of relaxin, progesterone, prolactin (PRL), and growth hormone (GH) during late pregnancy and lactation. Uterine surgical removal (hysterectomy) of nongravid gilts during the estrous cycle (day 8) extends luteal function to 150 days which is beyond the duration of normal pregnancy. Hysterectomy provides a useful model to examine shifts in hormone secretion at the time of expected parturition in gravid pigs. Blood samples were collected via an indwelling jugular cannula twice daily (0800 and 2000 hours) from days 90 to 120 and every 20 minutes within a 3-hour period on days 112 to 116. Relaxin and progesterone are hormones of ovarian origin, and PRL and GH are hormones secreted by the pituitary gland. Parturition occurred earlier (day 114) in Yorkshire than Meishan (day 115) gilts. The prepartum peak relaxin release occurred about 16 hours earlier in both breeds, thereafter relaxin dropped to basal levels during lactation. After hysterectomy, relaxin plasma levels were consistently greater in Meishan compared with Yorkshire gilts from days 110-118. A programmed peak relaxin release occurred one day earlier in Yorkshire compared with Meishan gilts. Following the relaxin peak, corpora lutea persisted in both breeds, but Meishan gilts continued to secrete consistently greater amounts of relaxin than Yorkshire gilts. Progesterone plasma levels remained higher longer in late pregnant Meishan compared with Yorkshire gilts. After hysterectomy, progesterone plasma levels were consistently higher in Meishan compared with Yorkshire gilts from days 101 to 118. Prolactin circulating concentration increased during late pregnancy and early lactation, but at a higher level in Yorkshire compared with Meishan gilts. Growth hormone blood levels increased only during late pregnancy and early lactation in both Meishan and Yorkshire gilts. These results indicate significant differences in the timing, and in some cases, magnitude of hormone secretion profiles in pregnant and hysterectomized Yorkshire and Meishan gilts

Fundamental differences in the radio properties of red and blue quasars: insight from the LOFAR Two-metre Sky Survey (LoTSS)

Red quasi-stellar objects (QSOs) are a subset of the luminous end of the cosmic population of active galactic nuclei (AGN), most of which are reddened by intervening dust along the line-of-sight towards their central engines. In recent work from our team, we developed a systematic technique to select red QSOs from the Sloan Digital Sky Survey (SDSS), and demonstrated that they have distinctive radio properties using the Faint Images of the Radio Sky at Twenty centimeters (FIRST) radio survey. Here we expand our study using low-frequency radio data from the LOFAR Two-metre Sky Survey (LoTSS). With the improvement in depth that LoTSS offers, we confirm key results: compared to a control sample of normal “blue” QSOs matched in redshift and accretion power, red QSOs have a higher radio detection rate and a higher incidence of compact radio morphologies. For the first time, we also demonstrate that these differences arise primarily in sources of intermediate radio-loudness: radio-intermediate red QSOs are × 3 more common than typical QSOs, but the excess diminishes among the most radio-loud and the most radio-quiet systems in our study. We develop Monte-Carlo simulations to explore whether differences in star formation could explain these results, and conclude that, while star formation is an important source of low-frequency emission among radio-quiet QSOs, a population of AGN-driven compact radio sources are the most likely cause for the distinct low-frequency radio properties of red QSOs. Our study substantiates the conclusion that fundamental differences must exist between the red and normal blue QSO populations

Selection on Floral Morphology and Environmental Determinants of Fecundity in a Hawk Moth-Pollinated Violet

This paper presents the results of a 5—yr field study on the determinants of individual variation in maternal fecundity (seed production) in the narrowly endemic violet Viola cazorlensis (Violaceae), at a southeastern Spanish locality. Flowers of this species are characterized by a very long, thin spur and broad morphological variability, and are pollinated by a single species of day—flying hawk moth (Macroglossum stellatarum; Lepidoptera, Sphingidae). The primary aim of this investigation was to answer the question, What are the relative importances, as explanations of individual differences in fecundity, of variability in floral traits and of other fecundity determinants that are of an extrinsic nature, such as microhabitat type and interactions with herbivores? The floral morphology of individual V. cazorlensis plants was characterized by means of both "conventional," linear measurements of the size of flower parts (petals, spur, peduncle), and shape analysis of corolla outline (using thin—plate splines relative warps analysis). Spatial (among substrate types) and temporal (among years) patterns of variation in flower, fruit, and seed production by V. cazorlensis plants are described, with particular emphasis on the comparative effects of floral morphology, herbivory (by mammalian ungulates and two species of lepidopteran larvae), and substrate type (rock cliffs, bare rocks at ground level, and sandy soils), on cumulative seed production at the individual plant level. Cumulative seed production of individual V. cazorlensis plants depended significantly on average floral morphology (both size and shape components), thus revealing the existence of phenotypic selection on the floral morphology of this species at the study population. Among all the floral traits examined, spur length was the only one for which no significant relationship with fecundity was found. Type of substrate largely determined differences between V. cazorlensis plants in the impact of herbivory (plants growing on the soil exhibited the greatest reproductive losses to herbivores), and it also influenced plant size and flower production per reproductive episode. Plant size, in turn, influenced the supra—annual frequency of flowering and the number of flowers produced in each reproductive event. Flower production and herbivory levels significantly influenced (positively and negatively, respectively) fruit number, which was the major direct determinant of seed production. Path analysis revealed that the main determinants of individual variation in cumulative seed production over the study period were, in decreasing order of importance (absolute value of "effect coefficient" in parentheses), cumulative fruit production (0.946), mean flower production per reproductive event (0.868), plant size (0.441), herbivory by ungulates (—0.221), and average score on the first relative warp (0.107), a descriptor of flower shape. After accounting for the effects of substrate type, herbivory, plant size, and flower and fruit production, individual variation in floral morphology (aspects of size and shape) explained a negligible proportion (2.1%) of total individual variation in cumulative fruit production. Phenotypic selection on the floral morphology of V. cazorlensis at the study population, although statistically significant, was therefore almost inconsequential as a source of individual variation in maternal fitness, its effects being heavily "dilute" by the overwhelming influence of other factors. As exemplified by this study, selection on the floral phenotype may often become largely irrelevant in evolutionary terms because other ecological factors are far more important determinants of fitness differences among plants. A realistic assessment of the potential relevance of selection on plant reproductive traits thus requires a quantitative evaluation, in its natural scenario, of the predictable consequences of such selectionPeer reviewe

TRH: Pathophysiologic and clinical implications

Thyrotropin releasing hormone is thought to be a tonic stimulator of the pituitary TSH secretion regulating the setpoint of the thyrotrophs to the suppressive effect of thyroid hormones. The peptide stimulates the release of normal and elevated prolactin. ACTH and GH may increase in response to exogenous TRH in pituitary ACTH and GH hypersecretion syndromes and in some extrapituitary diseases. The pathophysiological implications of extrahypothalamic TRH in humans are essentially unknown. The TSH response to TRH is nowadays widely used as a diganostic amplifier in thyroid diseases being suppressed in borderline and overt hyperthyroid states and increased in primary thyroid failure. In hypothyroid states of hypothalamic origin, TSH increases in response to exogenous TRH often with a delayed and/or exaggerated time course. But in patients with pituitary tumors and suprasellar extension TSH may also respond to TRH despite secondary hypothyroidism. This TSH increase may indicate a suprasellar cause for the secondary hypothyroidism, probably due to portal vessel occlusion. The TSH released in these cases is shown to be biologically inactive