Period Of Most Rapid Increase Research Articles

The evolution of State-Local balance sheets in the United States, 1953–2013

State and local debt in the United States more than doubled as a share of gross domestic product between 1953 and 2007. Using a historical accounting framework, we find that there is no straightforward relationship over time between state and local deficits and debt growth. We find that only 17 percent of the variation in aggregate state–local debt ratios comes from variation in the fiscal balance. This is especially true in the 1980s, the period of most rapid increase in state–local debt ratios. Before 1980, there were small but persistent deficits, but stable debt ratios. In the 1980s, state and local sectors shifted toward budget surpluses but saw rising debt ratios. This is explained by a faster pace of asset accumulation. Our results demonstrate the autonomy of balance sheet variables and suggest that changing debt ratios cannot be explained by real income and expenditure flows.

Mechanical modulation of cartilage structure and function during embryogenesis in the chick.

The mechanical behavior of cartilage is intimately related to its biochemical composition, and tissue composition is known to be influenced by its local mechanical loading environment. Although this phenomenon has been well-studied in adult cartilage, few investigations have examined such structure-function relationships in embryonic cartilage. The goal of this work was to elucidate the role of mechanical loading on the development of cartilage composition during embryogenesis. Using an embryonic chick model, cartilage from the tibiofemoral joints of immobilized embryos was compared to that of controls. The normal time course of changes in glycosaminoglycan/DNA and hydroxyproline/DNA were significantly influenced by loading history, with the most pronounced effects observed between days 9 and 14 during the period of most rapid increase in motility in control embryos. Stress-relaxation tests conducted on samples from day 14 indicate that the effects of embryonic immobilization on cartilage matrix composition have direct consequences for the mechanical behavior of the tissue, resulting in compromised material properties (e.g. 50% reduction in E(inst)). Because embryogenesis provides a unique model for identifying key factors which influence the establishment of functional biomechanical tissues in the skeleton, these data suggest that treating mechanical loading as an in vitro culture variable for tissue engineering approaches to cartilage repair is likely to be a sound approach.

A 13C-Pulse-labeling study of phytoalexin biosynthesis in hypersensitively responding cotton cotyledons

Time courses of multiplication of an incompatible strain of Xanthomonas campestris pv. malvacearum, accumulation of phytoalexins, and development of phytoalexin-rich, yellow-green fluorescent, hypersensitively necrotic cells were followed in cotton cotyledons. Occasionally, hypersensitively responding palisade cells were seen to pass through a stage in which the yellow-green fluorescence, due to the phytoalexins lacinilene C and its methyl ether, was confined to the cytoplasmic layer surrounding an intact vacuole, but more often, when cells became yellow-green fluorescent, the fluorescence appeared throughout the cell. The period of most rapid increase in fluorescent cell numbers, 48-72 h post-inoculation, was also the period of most rapid increase in phytoalexin content, and the rate of bacterial multiplication began to slow down at this time. Stable 13C isotope incorporation from a 4 h pulse with [13C2]acetate into the phytoalexin 2,7-dihydroxycadalene and its methyl ether was measured by direct probe electron impact-mass spectrometry to monitor their biosynthesis at 2, 3, 4, and 6 days after inoculation. Highest incorporation rates occurred during the period of most rapid increase in numbers of fluorescent cells, consistent with the hypothesis that these cells achieve a burst of phytoalexin biosynthesis causing them to become fluorescent as they die. In addition, biosynthesis was still active when fluorescent cell numbers approached their maximum and was appreciably above zero 1 and 2 days later, which suggests the possibility that healthy cells neighboring the hypersensitively responding ones contribute to the biosynthesis of phytoalexins in cotton.

Planktonic Growth of Larval Lobster (Homarus americanus) off îles de la Madeleine (Quebec), Gulf of St. Lawrence

The carapace length of the three planktonic larval and one postlarval stages of Homarus americanus was measured for larvae collected off îles de la Madeleine over three summers. Mean larval size did not vary between years or locations around the islands. The size of stages I and II remained constant throughout the summer, but after molting into stages III and IV, larvae diminished in size through the summer. Size frequency distribution became more scattered as larvae grew into more advanced stages. The increase of variance with size between stages I–IV followed the same progression as that observed between stages V–XIII, allowing prediction of the variance associated with mean size at each stage. The size of stage I larvae collected in nine regions along the Atlantic coast was not correlated with the July surface water temperature or with the smallest female size at maturity. Comparison of various body proportions suggested that a single morphometric measurement is not sufficient to describe geographical variations in size. Percentage growth per molt decreased with each successive molt. During summer, increment at molt decreased and molt frequency increased. Larval growth rates followed closely the temperature regime, with maximum growth rate attained during the warmest period of the summer (July 30 – August 9). The duration of the first three larval stages estimated from field data was of 24 d compared with 21 d calculated from previous laboratory studies. The maximum abundance of stage I larvae was synchronized with the period of most rapid increase in summer temperature, thus insuring that larvae achieved highest net growth rates through their planktonic phase.

Delayed ontogenesis of histamine in the hypothalamus of the homozygous Brattleboro rat.

The ontogenetic development of histamine was studied in the diabetes insipidus rat to clarify the possible interference between the lack of vasopressin and the development of histaminergic systems in the hypothalamus. Rat pups were decapitated at different ages between the 2nd and 38th postnatal days. In addition to homozygous Brattleboro (diabetes insipidus) rats, Long Evans controls and heterozygous animals were studied. In all three genotypes hypothalamic histamine was almost equal during the first 6 postnatal days. In homozygous Brattleboro rats the period of most rapid increase occurred between days 14 to 26, which was significantly later than in Long Evans rats. In the remainder of the brain no such difference was seen. On the contrary, histamine values were highest in the youngest animals. It remains to be elucidated whether the delayed ontogenesis is causally related to vasopressin deficiency and what is the underlying mechanism.

Localization, chromatographic characterization, and development of somatostatin-like immunoreactivity in the guinea pig retina

We have studied the anatomical localization, chromatographic properties, and development of somatostatin-like immunoreactivity (SLI) in the guinea pig retina. The majority of guinea pig retinal SLI in the adult and fetus eluted similarly to somatostatin-28 by gel filtration and high pressure liquid chromatography. This represents a higher ratio of somatostatin-28-like material to total SLI than had been observed in retinal extracts from most other animal species. Somatostatin-like-immunoreactive cells and fibers were localized using two antisera in cryostat-sectioned and flat mounted retinae. Distribution of cells and fibers differed uniquely from that in other species previously reported. Reactive perikarya were located only in the far peripheral region: in the innermost layer of the inner nuclear layer (INL), in the inner plexiform layer (IPL), and in the ganglion cell layer. Reactive fibers were prominent in the IPL and nerve fiber layer (NFL) in both the peripheral and central retina. Less frequently, processes were observed between the NFL and IPL, between the IPL and INL, and, rarely, in the outer plexiform layer and outer nuclear layer. Small numbers of reactive fibers were found in the optic nerve and disc. These observations suggest that processes of intrinsic (amacrine or associational ganglion cells) and projection neurons (true ganglion cells or efferent fibers) containing SLI are intermingled in the guinea pig retina. SLI, quantified by radioimmunoassay, was present in the developing retina as early as the 6th week of gestation (full term is 10 weeks). Immunohistochemically detected somatostatin-like-immunoreactive elements were seen first at 2 weeks before birth, coincident with the onset of the period of most rapid increase in levels of assayed SLI. Somatostatin-like-immunoreactive peptides reached two-thirds of adult levels by birth.

Concentrations of Chlorogenic Acid, Oil, and Fatty Acids in Developing Sunflower Seeds1

The concentrations of chlorogenic acid, oil, and fatty acids were determined during the development and maturation of sunflower seeds (Helianthus annuus L.). When the cultivars ‘Krasnodarets’ and ‘Peredovik’ were sampled at 4‐day intervals from 5 to 29 days after flowering (DAF), the average chlorogenic acid concentration of hull‐free sunflower meal declined from an initial value of 0.40% to 0.18% at 9 DAF, then steadily increased to 1.96% by 29 DAF. This latter value represented three.quarters of the total chlorogenic acid deposited. The change in oil and chlorogenic acid concentrations followed relatively similar patterns (r = 0.93, at the 0.01 level, 25 dr). However, oil content did not decline during the first week and the period of most rapid increase in oil content occurred about 5 to 7 days before that of chlorogenic acid. The proportion of paimitic acid in the total fatty acids declined from an average of 26% at 5 DAF to 6.5% at 29 DAF, whereas linoleic acid declined from 49.6% at 5 DAF to 38.4% at 13 DAF then steadily increased to 67.0% at 29 DAF. This pattern was partially due to the presence of up to 12% linolenic, arachidic and behenie acids in imma. ture seeds, followed by their virtual disappearance by 17 DAF. Additional sampling between 21 and 49 DAF confirmed that most of the chlorogenic acid in sunflower seeds is synthesized between 13 and 35 DAF with the highest rate occurring between 21 and 28 DAF. Because maximum seed weight, oil content, and chlorogenic acid concentration coincide, it would not be practical to reduce chlorogenic acid levels in seeds by early harvesting.

Ammonium Influence on the Growth and Nitrate Reductase Activity of Paul's Scarlet Rose Suspension Cultures

Suspension cultures of Paul's Scarlet rose were grown in two defined media which differed only in their inorganic nitrogen content. Both possessed equal amounts of NO(3) (+) (24 mm), but differed in that NH(4) (+) (0.91 mm) was present in control medium; whereas, no NH(4) (+) was present in the test medium. A comparison of fresh weight increases over a 14-day growth period showed that NH(4) (+) caused a 2-fold stimulation in growth and governed the pattern of development.Ammonium also caused a 2-fold increase in nitrate reductase activity but had little influence on the activity of representative enzymes from the Embden-Meyerhof pathway or citric acid cycle. Thus NH(4) (+) enhanced the nitrate reductase activity which was correlated with increased growth.Ammonium had no influence on the in vitro activity of nitrate reductase which suggested that the stimulatory influence was due to an increased synthesis of the enzyme. The enhanced synthesis did not appear to be due to an increased availability of NO(3) (+) since the uptake of NO(3) (+) by intact cells was not influenced by the presence of NH(4) (+) during the period of most rapid increase in nitrate reductase activity.

Biosynthesis of soluble α-Glycerophosphate dehydrogenase during the adult development after emergence of the sheep blowfly Lucilia

α-Glycerophosphate dehydrogenase (αGPDH) was purified to a specific activity of greater than 200 and purity was assessed by polyacrylamide gel electrophoresis. Incorporation of [ 14C]leucine into purified αGPDH was measured in newly emerged 1-, 2- and 5-day-old female flies, and the free leucine pool-size and turnover rate were determined for each age. From this the rate of formation of the enzyme from [ 14C]leucine was calculated and compared to that based on the appearance of enzyme activity; protein synthesis de novo from the amino-acid pool was found to account adequately for the appearance of activity over the period of most rapid increase of the enzyme. Protein synthesis de novo was also demonstrated by the uniform incorporation of radioactivity into the enzyme using peptide mapping and autoradiography and by the inhibition (99 per cent) of the incorporation of radioactivity by cycloheximide.

Studies on the production relations of deciduous forests of semi-arid zone of Rajasthan (India)

The observations on the biomass and net production ofAdina cordifolia forms a part of the scheme “Primary productivity of deciduous forests of semi-arid regions near Udaipur (IBP/PT programme—India/PT/7)”. The study area, Borimalan forest block in Prasad range is situated 54 km south of Udaipur town (24,11’N and 73,42’E). From the present study it is concluded that: 1. Dry weight of different plant parts increases with age. The period of most rapid increase was observed between 26–27 growth rings. 2. The net above ground biomass in this tree species has been observed to be 6,5×103 kg/ha. 3. The average increment in non-photosynthetic above ground biomass has been observed to range between 0,94 kg/gr to 6,92 kg/gr. 4. The values for shoot net production/leaf area, has been found to vary between 180 and 240 g/m2. 5. Comparison of biomass production in this tree species has been made with other tropical or temperature forest tree species of comparable age and the possible causes of difference in biomass production are discussed.

Changes in brain and sciatic nerve composition with development of the rhesus monkey ( macaca mulatta)

We determined the composition of the brain and sciatic nerves of 135 rhesus monkeys (Macaca mulatta) ranging from 58 days gestational age to over 10 years. The period of most rapid increase in size is prior to birth, and at birth the brain is about 70% of adult size. The patterns of change in weight, protein, and DNA of the cerebellum indicate that this area matures later and grows more rapidly than the remainder of the brain. The concentrations (per gram wet weight) of protein increase at all sites in the brain, but those of DNA decrease during the period of most rapid growth. The concentrations of all lipids, particularly those most characteristic of myelin, were much higher in pons, cervical cord, and sciatic nerve than in cortical gray matter. The concentration of those lipids most typical of myelin were essentially absent from the pons at 100 days of gestation, reached more than one-half of adult values at birth, but continued to increase after one year. Cerebrosides and sulfatides most nearly followed that pattern in the pons. The concentrations of sphingomyelin, plasmalogen forms of phosphatidylethanolamine, and cholesterol were the next best indicators of myelination, whilst the concentrations of combined phospholipids, lecithin, phosphatidylserine, and diacyl phosphatidylethanolamine changed less than the first two classes of compounds.

DISTRIBUTION AND ABUNDANCE OF SITONA HISPIDULA (F.) AND THE EFFECT OF INSECT INJURY ON ROOT DECAY OF RED CLOVER IN THE MARITIME PROVINCES

Insect injury to red clover by root-feeding weevils, mainly the clover root curculio (Sitona hispidula (F.)), and the association with root decay were investigated by periodic examinations of roots during 1965 and 1966. The abundance of Sitona spp. was also recorded from soil samples taken with the root samples. Greatest injury to the roots was observed during June and July of the first year of production, when larval populations were highest. The period of most rapid increase in the external decay of roots coincided with peak larval populations and the resulting increase in feeding injury. With increased severity of insect injury the external decay and, to a greater extent, the internal decay increased. During the period of these studies S. hispidula was widely distributed throughout the Maritime Provinces and was sufficiently abundant to be considered of economic importance.

Hypoxanthine dehydrogenase in the developing chick embryonic kidney.

SummaryThe activity of hypoxanthine dehydrogenase was determined in mesonephric and metanephric renal tissue of the chicken embryo and related to the amount of soluble protein in these tissues during successive stages of incubation. The period of most rapid increase of specific activity occurred at days 6 and 7 in the mesonephros and at days 13 to 15 in the metanephros. The highest specific activity was obtained on day 14 in the mesonephric tissue which in the subsequent period of incubation exhibited decreasing hypoxanthine dehydrogenase activity. The metanephric tissue, which becomes the functional kidney of the chicken, attained a plateau of hypoxanthine dehydrogenase activity by the 16th day.