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The volatile organic compound (VOC) emission characteristics of various production procedures were analyzed through GC-MS after the emissions of typical enterprises such as automobile manufacturing, petrochemical, and other industries had been sampled with SUMMA canisters. Each production procedure in the automobile manufacturing and petrochemical industries was considered. The results showed that each automobile manufacturing procedure had its own dominant species, and alkanes (32%) and aromatics (35%) were the main emission species of coating spraying. The emission characteristics of furniture manufacturing were highly correlated with the raw materials, and the VOC emission species were mainly composed of aromatics (50%) and oxygenated VOCs (OVOCs) (38%). As for the petrochemical industry, VOC concentrations in various process plant areas ranged from 49 μg·m

The purpose of this paper is to develop an emission inventory of anthropogenic air pollutants and VOCs species in Sichuan Province. Based on the anthropogenic source activity data collected in different cities of Sichuan Province and the selected emission factors, the 1 km × 1 km gridded atmospheric air pollutant emission inventory of 2015 was developed in the “bottom-up” and “top-down” approaches with the GIS technology. The results showed that the emissions of SO2, NOX, CO, PM10, PM2.5, BC, OC, VOCs and NH3 from anthropogenic sources in Sichuan Province were 444.9 kt, 820.0 kt, 3773.1 kt, 1371.6 kt, 537.5 kt, 28.7 kt, 53.1 kt, 923.6 kt and 988.0 kt, respectively. Power plants and other industrial combustion boilers contributed more than 95% of SO2 emission. Transportation, fossil fuel burning and industrial process contributed 54%, 23% and 20% of NOx emission respectively. Industrial process dominated by steel production and building material manufacturing contributed 20% of PM10 emission and 34% of PM2.5 emission. Fugitive dust dominated by road fugitive dust contributed 60% of PM10 emission and 35% of PM2.5 emission respectively. Biomass burning contributed 33% of BC emission and 51% of OC emission respectively. Solvent use of mechanical processing, building decoration, electronic equipment manufacturing, printing and furniture industry contributed 46% of VOCs emission. NH3 mainly came from the emission of agricultural sectors, such as livestock breeding and N-fertilizer application, which contributed 70% and 25% of NH3 emission respectively. The percentage of alkanes, alkenes, alkynes, aromatics, OVOCs, halohydrocarbons and other VOCs in the total VOCs emission were 17%, 9%, 2%, 23%, 22%, 4% and 23%, respectively. Ethene, m-xylene, toluene, propene, formaldehyde, o-xylene, 1, 2, 4-trimethyl benzene, 1-butene, p-xylene and ethyl benzene were the most critical chemical species for the formation of ozone pollution in Sichuan Province contributing 50% of the total OFP. Various air pollutants and OFP were mainly distributed in places with the densest population and well-developed agriculture and industry in Sichuan Basin and some areas of Panzhihua. The Chengdu Plain urban agglomerations, represented by Chengdu, Deyang and Mianyang, were the main areas with concentrated pollutant emissions in Sichuan Basin.

The characteristics of volatile organic compound (VOCs) species from various production procedures of wood-based panel production and other industrial processes in Chengdu were analyzed through gas chromatography-mass spectrometry (GC-MS) and other methods specified in national standards after the emissions of typical enterprises of wood-based panel production, pharmaceutical manufacturing, chemical production and other industrial processes in Chengdu had been sampled using sampling bottles and SUMMA canisters. Generally, the process of wood-based panel production includes glue making, glue mixing, sorting, and hot pressing, whereas the process of pharmaceutical manufacturing includes workshop production and wastewater treatment. The results showed that the main contribution species of VOCs in wood-based panel production and pharmaceutical manufacturing is oxygenated VOCs (OVOCs), accounting for more than 50% of the total VOCs emitted. The species from organized and unorganized emissions of formaldehyde manufacturing differed significantly. The main species of organized emissions was OVOCs, and that of unorganized emissions was halohydrocarbons. Emissions of VOCs from coating manufacturing were strongly correlated with the raw materials, and the corresponding emission species were composed mainly of aromatics and OVOCs. Except for glue mixing, the main species of VOCs in other process procedures of wood-based panel production was formaldehyde, with emission proportion of more than 50%. The primary species of VOCs in various processes of pharmaceutical manufacturing was ethanol; however 1,4-dioxane, ethyl acetate, and toluene were also important species. Moreover, the main VOCs from formaldehyde manufacturing were composed mainly of acetone and ethanol, and those of coating manufacturing were aromatic hydrocarbons such as p-xylene. The ozone formation potential was to characterize the reactivity of pollution sources in VOCs from wood-based panel production, pharmaceutical manufacturing, and chemical production. The results showed that the species of VOCs in different industries contributed similarly to the reactivity and that these species were mainly high-activity species such as formaldehyde, ethanol, and other OVOCs as well as some aromatic hydrocarbons. Therefore, supervision and regulation of enterprises of industrial processes is required with a focus on species with relatively large ozone formation potential. In addition, it is necessary to analyze the emission characteristics and chemical mechanism of various industries and to control O

Based on the measured data in the literature, VOCs (volatile organic compounds) source profiles were revised and reconstructed without OVOCs (oxygenated volatile organic compounds) species to obtain the normalized VOCs source profiles. Using the 2015 Sichuan emission inventory, source profiles based on the 1 km×1 km gridded speciated VOCs emission inventory were developed, and the ozone formation potentials of the species were estimated to assess the environmental impact on ozone formation. The established VOCs source profile database consists of 45 source profiles and 519 species. Since the source profiles were established based on the revision and reconstruction of pollution sources, such as biomass burning and transportation, that are rich in OVOCs, the source profile database is better applicable to establishing the speciated VOCs emission inventory and source apportionment. The speciated VOCs emission inventory showed that the total anthropogenic emission of VOCs in Sichuan Province was 773.8 kt, of which the emissions of alkanes, olefins, alkynes, aromatics, OVOCs, halohydrocarbons, and other VOCs accounted for 21.6%, 10.0%, 1.7%, 28.0%, 26.2%, 4.2%, and 8.3% of the total respectively. The total OFP (Ozone formation potential) was 2584.9 kt, of which the OFPs of the VOCs groups mentioned above accounted for 6.9%, 26.1%, 0.5%, 42.3%, 23.2%, 0.4%, and 0.5% respectively. The main VOCs species emitted in all cities of Sichuan Province were aromatics, OVOCs, and alkanes; however, there were some significant regional differences:transportation in Chengdu, Ya'an, Aba, Ganzi, and Liangshan made a greater contribution to VOCs emissions, with alkane emissions accounting for a higher proportion in the total VOCs emission. As a heavy industrial city, Panzhihua suffered most from emissions from industrial processes, which contain a relatively high proportion of alkanes. Solvent use in Deyang, Meishan, Suining, and Ziyang made a great contribution to the VOCs emissions, and the OVOCs emission was relatively high. Emissions of VOCs and species with relatively high OFPs in Sichuan Province were mainly distributed in the Sichuan Basin, which has a dense population and highly developed industry, as well as some areas in Liangshan and Panzhihua. The main source of

Based on anthropogenic source activity data and emission factors for the Sichuan Province, the 1 km×1 km-gridded atmospheric air pollutant emission inventory of 2015 was developed in combination with GIS technology and the combined "bottom-up" and "top-down" construction method. The results show that the total emission of SO

Rapamycin is a potent antiproliferative agent that arrests cells in the G1 phase of the cell cycle through a variety of mechanisms involving the inhibition of the mammalian target of rapamycin (mTOR) pathway. The majority of normal cells in culture are sensitive to the cytostatic effects of rapamycin, whereas the growth of many malignant cells and tumors is rapamycin resistant. We had shown previously that hepatic DNA synthesis in the late gestation rat fetus is rapamycin resistant even though signaling through the mTOR/S6 kinase (S6K) pathway is attenuated. On the basis of this finding, we went on to characterize the response to rapamycin in a spectrum of tissues during late gestation and the early postnatal period in the rat. We found that rapamycin had no effect on DNA synthesis in major organs such as heart, intestine, and kidney in the fetal and early postnatal rat despite a marked attenuation in the phosphorylation of ribosomal protein S6. In contrast, the proliferation of mature hepatocytes during liver regeneration was highly sensitive to rapamycin. These data indicate that basal cellular proliferation in a wide variety of tissues is rapamycin resistant and occurs independently of mTOR/S6K signaling. Furthermore, the well-characterized effects of rapamycin in tissue culture systems are not recapitulated in the asynchronous cell proliferation that accompanies normal growth and tissue remodeling.

The ATDC5 chondrogenic cell line is typically induced to differentiate by exposure to insulin at high concentration (10 microg/ml, approximately 1600 nM). Differentiation can also be induced by physiological concentrations of insulin-like growth factor-I (IGF-I). Unlike previous reports, we observed a stimulation of differentiation, as measured by collagen X expression and Alcian Blue staining for proteoglycan synthesis, upon exposure to insulin at concentrations (10-50 nM) consistent with signaling via the insulin receptor. Analysis of lysates from proliferating and hypertrophic ATDC5 cells demonstrated that exposure to 50 nM insulin induced tyrosine phosphorylation of insulin receptors but not IGF-I receptors or hybrid receptors. In contrast to the potent effects of IGF-I to stimulate both ATDC5 proliferation and differentiation, insulin was not as potent as IGF-I as a proliferating agent but more selectively a differentiating agent. Consistent with this result, insulin was less potent than IGF-I in inducing activation of the Erk1/Erk2 mitogenic signaling pathway. Furthermore, Erk pathway inhibition did not enhance the differentiating effects of insulin as it does in the case of IGF-I exposure. Extending our observations to fetal rat metatarsal explants, we observed significant stimulation of bone growth by 50 nM insulin. This could be accounted for by a disproportionate stimulatory effect on growth of the hypertrophic zone. The proliferative zone was not significantly affected. Based on our results in both ATDC5 cells and metatarsal explants, we conclude that the insulin functioning through insulin receptor has a dominant effect as an inducer of chondrocyte differentiation. These results support assignment of a physiological role for this hormone in linear bone growth.

Antenatal glucocorticoids are routinely given to women at risk for preterm delivery. The fetus is protected from excessive glucocorticoids by the placental enzyme 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD-2), which catalyzes the conversion of cortisol to its biologically inactive metabolite, cortisone. We examined the effects of antenatal dexamethasone on the expression of placental 11beta-HSD-2 in fetal sheep. Ewes were randomized to receive repeated or single courses of dexamethasone or placebo beginning at 76-78 or 104-106 d of gestation, respectively. In the single course group, the ewes received dexamethasone (6 mg, n = 7) or placebo (n = 6) as four intramuscular injections over 48 h up to 18 h before placental harvest. In the repeated course group, the ewes received the same treatment (dexamethasone, n = 10, or placebo, n = 9) once a week for 5 consecutive weeks starting at 76-78 d of gestation. Placental harvest occurred at 106-108 d of gestation in the four groups. By semi-quantitative RT-PCR, we found that placental 11beta-HSD-2 expression was lower in the fetuses of ewes exposed to a single course of dexamethasone than placebo (p0.05). Placental 11beta-HSD-2 expression did not differ significantly between fetuses of ewes treated with repeated courses of dexamethasone compared with placebo, or a single course of dexamethasone. Fetuses of dexamethasone treated ewes weighed less than those of placebo treated ewes (ANOVA, main effects for dexamethasone versus placebo treatment: F = 14.5, p = 0.007). Fetuses of ewes exposed to repeated courses of dexamethasone weighed less than those of ewes exposed to placebo or a single course of dexamethasone (p0.05). We conclude that maternal antenatal dexamethasone treatment reduces placental 11beta-HSD-2 expression and fetal weight at mid-gestation in the ovine pregnancy.

We put forward a novel non-planar single-frequency ring laser, which consists of a corner cube prism and a specially cut Porro prism made by Nd:YAG crystal. The relative angle between the corner cube and the Porro prism could be adjusted to control the output coupling of the laser resonator and the polarization-state of the output laser. A 1.06 μm single-frequency laser with 1 W output has been obtained.

Factors responsible for hypertension in the spontaneously hypertensive rat (SHR) remain under investigation. As in human pregnancy complicated by essential chronic hypertension, the hypertension of the pregnant SHR subsides and returns postpartum. Because corticosteroid excess can cause hypertension, we examined several aspects of adrenocortical activity as potentially affecting the reported blood pressure profiles of nonpregnant, term pregnant, and postpartum SHR, using normotensive Wistar-Kyoto (WKY) rats as controls. We found that corticosterone levels were comparable in nonpregnant SHR and WKY rats, and unaffected by pregnancy. No differences were detected postpartum. Although pregnancy was accompanied by significant increases in plasma aldosterone levels, no interbreed differences were observed, which remained the case postpartum. Single adrenal cell secretion of aldosterone and corticosterone, as detected by reverse hemolytic plaque assay, yielded similar results in the pregnant and postpartum rat. Hormone responses to dietary manipulations in the nonpregnant and pregnant SHR and WKY suggest an important role for ACTH, and a lesser one for AII in the regulation of corticosteroids. In situ hybridization histochemistry, using a probe that detects both P450c11β and P450c11AS mRNA, revealed comparable message density and zonal distribution in adrenals from pregnant and nonpregnant SHR and WKY rats. Breed- and pregnancy-dependent differences in adrenal expression of P450scc, P450c11β, and P450c11AS were noted. In summary, our findings suggest that although some discrepancies exist in the aspects of adrenocortical activity examined, they are unlikely to be etiologic in the blood pressure profile observed in nonpregnant, pregnant, and postpartum SHR.

Offspring of diabetics are at increased risk for diabetes as adults. As corticosteroids are intimately involved in glucose homeostasis, we investigated aspects of corticosteroid activity in the late gestation fetuses of control, moderately diabetic and insulin-controlled streptozotocin-induced diabetic rats. We found that moderate maternal diabetes had no effect upon litter size or fetal body weight. Uncontrolled maternal diabetes was accompanied by fetal hyperglycemia, hyperinsulinemia and elevated aldosterone. Maternal insulin treatment normalized fetal glucose and aldosterone; fetal insulin and corticosterone levels increased. Maternal diabetes had no effect upon fetal adrenal expression of P450scc mRNA; the abundance of P450c11β mRNA increased, and returned to that of the control gestation upon insulin treatment. P450c11AS mRNA was barely detectable, and decreased in the fetuses of insulin-treated diabetics. P450c11B3 mRNA was undetectable in all fetal groups. Our results implicate aspects of maternal diabetes in the expression of a fetal adrenocortical imprint, manifested as a greater abundance of P450c11β mRNA. Although not accompanied by elevated corticosterone in the fetus, this imprint could ultimately allow for greater potential corticosterone production in response to typical stimuli, and thus contribute to the tendency towards glucose dysregulation in these offspring of diabetic gestations.

Surveys using rRNA-targeted probes specific for the 3 domains of life (Eucarya, Archaea, and Bacteria) indicated the presence, and at times high abundance, of archaeal rRNA in a variety of water masses surrounding Antarctica. Hybridization signals of archaeal rRNA contributed significantly to that of total picoplankton rRNA both north and south of the Polar Front in Drake Passage. Late winter surface water populations collected around the South Shetland Islands also yielded relatively high archaeal rRNA hybridization signals, approaching 10% or greater of the total rRNA. Summer samples collected in the western region of the Antarctic Peninsula and at McMurdo Sound in the Ross Sea region of Antarctica yielded lower amounts of archaeal rRNA in the surface waters, and higher levels of archaeal rRNA at depth (150 to 500 m). The hybridization data were compared to biological, chemical, and hydrographic information when possible. In surface waters, archaeal rRNA and chlorophyll a varied inversely. The data presented here further supports the hypothesis that planktonic archaea are a common, widespread and likely ecologically important component of Antarctic picoplankton assemblages. The presence of these archaea in circumpolar deep water suggests a conduit for their circumpolar transport around Antarctica via the Antarctic Circumpolar Current, as well as their export to the deep sea, or to intermediate waters of the South Atlantic via mixing at the polar front.

Molecular phylogenetic surveys have recently revealed an ecologically widespread crenarchaeal group that inhabits cold and temperate terrestrial and marine environments. To date these organisms have resisted isolation in pure culture, and so their phenotypic and genotypic characteristics remain largely unknown. To characterize these archaea, and to extend methodological approaches for characterizing uncultivated microorganisms, we initiated genomic analyses of the nonthermophilic crenarchaeote Cenarchaeum symbiosum found living in association with a marine sponge, Axinella mexicana . Complex DNA libraries derived from the host-symbiont population yielded several large clones containing the ribosomal operon from C. symbiosum . Unexpectedly, cloning and sequence analysis revealed the presence of two closely related variants that were consistently found in the majority of host individuals analyzed. Homologous regions from the two variants were sequenced and compared in detail. The variants exhibit >99.2% sequence identity in both small- and large-subunit rRNA genes and they contain homologous protein-encoding genes in identical order and orientation over a 28-kbp overlapping region. Our study not only indicates the potential for characterizing uncultivated prokaryotes by genome sequencing but also identifies the primary complication inherent in the approach: the widespread genomic microheterogeneity in naturally occurring prokaryotic populations.

The study adopts the research of undergraduates’ views on marriage and love, Egma Minnen av Bardndosnauppforstran (EMBU),Social science research solutions(SSRS) of 286"90s College student", discusses the 90s College students' view on love and marriage, Cultivation style, Social support and their relationship, and trying to build the relationship between structure equation model, the results showed that: (1) 90s College students' view of marriage and love somewhere in between traditional and modern. Surprisingly, 90s College students' erotic choice is unusual traditional (2) Different grade has different ideas on the view of marriage and love, grade four get the highest score and grade three get the lowest.(3) There is significant different grades on the view of marriage and love between girls and boys. Girls are more traditional than boys. (4) In the aspect of student origin, we can see the remarkable difference in different students. As a whole, the view on marriage and love of country students are the most traditional, town students are the most modern. (5)Student in different majors have the different ideas on the view of marriage and love. Liberal arts students are the most traditional, maybe a large number of them are girls were the reason. (6) Influences such as parental marital status and relationship or different inhabitancy circs have little impact on 90s College students' view on marriage and love. (7) Cultivation style and Social support can't directly affect attribution way sense of 90s College students' view on marriage and love, but they can impact of erotic choice directly. We can see 90s College students' Cultivation style and Social support attribution way a close relationship with their erotic choice on the view of their marriage and love.

Archaea, one of the three major domains of extant life, was thought to comprise predominantly microorganisms that inhabit extreme environments, inhospitable to most Eucarya and Bacteria. However, molecular phylogenetic surveys of native microbial assemblages are beginning to indicate that the evolutionary and physiological diversity of Archaea is far greater than previously supposed. We report here the discovery and preliminary characterization of a marine archaeon that inhabits the tissues of a temperate water sponge. The association was specific, with a single crenarchaeal phylotype inhabiting a single sponge host species. To our knowledge, this partnership represents the first described symbiosis involving Crenarchaeota. The symbiotic archaeon grows well at temperatures of 10 degrees C, over 60 degrees C below the growth temperature optimum of any cultivated species of Crenarchaeota. Archaea have been generally characterized as microorganisms that inhabit relatively circumscribed niches, largely high-temperature anaerobic environments. In contrast, data from molecular phylogenetic surveys, including this report, suggest that some crenarchaeotes have diversified considerably and are found in a wide variety of lifestyles and habitats. We present here the identification and initial description of Cenarchaeum symbiosum gen. nov., sp. nov., a symbiotic archaeon closely related to other nonthermophilic crenarchaeotes that inhabit diverse marine and terrestrial environments.

One potential approach for characterizing uncultivated prokaryotes from natural assemblages involves genomic analysis of DNA fragments retrieved directly from naturally occurring microbial biomass. In this study, we sought to isolate large genomic fragments from a widely distributed and relatively abundant but as yet uncultivated group of prokaryotes, the planktonic marine Archaea. A fosmid DNA library was prepared from a marine picoplankton assemblage collected at a depth of 200 m in the eastern North Pacific. We identified a 38.5-kbp recombinant fosmid clone which contained an archaeal small subunit ribosomal DNA gene. Phylogenetic analyses of the small subunit rRNA sequence demonstrated it close relationship to that of previously described planktonic archaea, which form a coherent group rooted deeply within the Crenarchaeota branch of the domain Archaea. Random shotgun sequencing of subcloned fragments of the archaeal fosmid clone revealed several genes which bore highest similarity to archaeal homologs, including large subunit ribosomal DNA and translation elongation factor 2 (EF2). Analyses of the inferred amino acid sequence of archaeoplankton EF2 supported its affiliation with the Crenarchaeote subdivision of Archaea. Two gene fragments encoding proteins not previously found in Archaea were also identified: RNA helicase, responsible for the ATP-dependent alteration of RNA secondary structure, and glutamate semialdehyde aminotransferase, an enzyme involved in initial steps of heme biosynthesis. In total, our results indicate that genomic analysis of large DNA fragments retrieved from mixed microbial assemblages can provide useful perspective on the physiological potential of abundant but as yet uncultivated prokaryotes.

The ATDC5 cell line exhibits a multistep process of chondrogenic differentiation analogous to that observed during endochondral bone formation. Previous investigators have induced ATDC5 cells to differentiate by exposing them to insulin at high concentrations. We have observed spontaneous differentiation of ATDC5 cells maintained in ascorbic acid-containing α-MEM. A comparison of the differentiation events in response to high-dose insulin vs. ascorbic acid showed similar expression patterns of key genes, including collagen II, Runx2, Sox9, Indian hedgehog, and collagen X. We took advantage of the action of ascorbic acid to examine signaling events associated with differentiation. In contrast to high-dose insulin, which downregulates both IGF-I and insulin receptors, there were only minimal changes in the abundance of these receptors during ascorbic acid-induced differentiation. Furthermore, ascorbic acid exposure was associated with ERK activation, and ERK inhibition attenuated ascorbic acid-induced differentiation. This was in contrast to the inhibitory effect of ERK activation during IGF-I-induced differentiation. Inhibition of collagen formation with a proline analog markedly attenuated the differentiating effect of ascorbic acid on ATDC5 cells. When plates were conditioned with ATDC5 cells exposed to ascorbic acid, ATDC5 cells were able to differentiate in the absence of ascorbic acid. Our results indicate that matrix formation early in the differentiation process is essential for ascorbic acid-induced ATDC5 differentiation. We conclude that ascorbic acid can promote the differentiation of ATDC5 cells by promoting the formation of collagenous matrix and that matrix formation mediates activation of the ERK signaling pathway, which promotes the differentiation program.

Linear growth in children is sensitive to nutritional status. Amino acids, in particular leucine, have been shown to regulate cell growth, proliferation, and differentiation through the mammalian target of rapamycin (mTOR), a nutrient-sensing protein kinase. Having recently demonstrated a role for mTOR in chondrogenesis, we hypothesized that leucine restriction, acting through mTOR, would inhibit growth plate chondrocyte proliferation and differentiation. The effect of leucine restriction was compared with that of the specific mTOR inhibitor, rapamycin. Leucine restriction produced a dose-dependent inhibition of fetal rat metatarsal explant growth. This was accounted by reduced cell proliferation and hypertrophy but not apoptosis. mTOR activity, as reflected by ribosomal protein S6 phosphorylation, was only partially inhibited by leucine restriction, whereas rapamycin abolished S6 phosphorylation. In chondrogenic ATDC5 cells, leucine restriction inhibited cell number, proteoglycan accumulation, and collagen X expression despite minimal inhibition of mTOR. Microarray analysis demonstrated that the effect of leucine restriction on ATDC5 cell gene expression differed from that of rapamycin. Out of 1,571 genes affected by leucine restriction and 535 genes affected by rapamycin, only 176 genes were affected by both. These findings indicate that the decreased chondrocyte growth and differentiation associated with leucine restriction is only partly attributable to inhibition of mTOR signaling. Thus nutrient restriction appears to directly modulate bone growth through unidentified mTOR-independent mechanisms in addition to the well-characterized mTOR nutrient-sensing pathway.

mTOR is a nutrient-sensing protein kinase that regulates numerous cellular processes. Our prior studies using the mTOR inhibitor, rapamycin, indicate an important role for mTOR in chondrogenesis. We extended our observations to a physiological, in vivo model of bone growth, direct infusion of rapamycin into the proximal tibial growth plates of rabbits. Rapamycin or DMSO vehicle was infused directly into growth plates by an osmotic minipump for 8 weeks. Tibial growth was followed radiographically. At the end of the experiment, growth plates were recovered for histological analysis. Six animals were studied. No untoward effects of rapamycin infusion were found. Bone growth of limbs exposed to rapamycin was slower than control limbs, particularly during the period of most rapid growth. Histological analysis revealed that growth plate height in the rapamycin-infused limbs was reduced. Both the hypertrophic and proliferative zones were significantly smaller in the rapamycin-infused limbs. Direct infusion of rapamycin into proximal tibial growth plates decreased the size of the growth plate and inhibited overall long bone growth. Rapamycin appears to affect both the proliferative and hypertrophic zones of the tibial growth plate. Our results indicate that nutrients may exert a direct effect on long bone growth via mTOR-mediated modulation of chondrogenesis at the growth plate. and suggest that the possible inhibitory effects of rapamycin on skeletal growth warrant further attention before its use in children.

The mammalian Target Of Rapamycin (mTOR) is a nutrient-sensing protein kinase that regulates numerous cellular processes. Fetal rat metatarsal explants were used as a physiological model to study the effect of mTOR inhibition on chondrogenesis. Insulin significantly enhanced their growth. Rapamycin significantly diminished this response to insulin through a selective effect on the hypertrophic zone. Cell proliferation (bromodeoxyuridine incorporation) was unaffected by rapamycin. Similar observations were made when rapamycin was injected to embryonic day (E) 19 fetal rats in situ. In the ATDC5 chondrogenic cell line, rapamycin inhibited proteoglycan accumulation and collagen X expression. Rapamycin decreased content of Indian Hedgehog (Ihh), a regulator of chondrocyte differentiation. Addition of Ihh to culture medium reversed the effect of rapamycin. We conclude that modulation of mTOR signaling contributes to chondrocyte differentiation, perhaps through its ability to regulate Ihh. Our findings support the hypothesis that nutrients, acting through mTOR, directly influence chondrocyte differentiation and long bone growth.

Insulin-like growth factor-I (IGF-I) is a critical regulator of skeletal growth. While IGF-I has been shown to be a potent chondrocyte mitogen in vitro, its role in chondrocyte differentiation is less well characterized. We chose to study the action of IGF-I on an accepted model of chondrocyte differentiation, the ATDC5 cell line. Insulin concentrations sufficiently high to interact with the IGF-I receptor are routinely used to induce ATDC5 cells to differentiate. Therefore, we first examined the ability of IGF-I to promote chondrocyte differentiation at physiological concentrations. IGF-I could induce differentiation of these cells at concentrations below 10 nM. However, increasing IGF-I concentrations were less potent at inducing differentiation. We hypothesized that mitogenic effects of IGF-I might inhibit its differentiating effects. Indeed, the extracellular-signal-regulated kinase (ERK)-pathway inhibitor PD98059 inhibited ATDC5 cell DNA synthesis while enhancing differentiation. This suggested that the ability of IGF-I to promote both proliferation and differentiation might require that its signaling be modulated through the differentiation process. We therefore compared IGF-I-mediated ERK activation in proliferating and hypertrophic chondrocytes. IGF-I potently induced ERK activation in proliferating cells, but minimal ERK response was seen in hypertrophic cells. In contrast, IGF-I-mediated Akt activation was unchanged by differentiation, indicating intact upstream IGF-I receptor signaling. Similar findings were observed in the RCJ3.1C5.18 chondrogenic cell line and in primary chick chondrocytes. We conclude that IGF-I promotes both proliferation and differentiation of chondrocytes and that the differentiation effects of IGF-I may require uncoupling of signaling to the ERK pathway.

Kane and Byer reported the first monolithic non-planar miniature ring laser in 1985. An intrinsic optical diode enforces unidirectional and hence single-frequency oscillation of this device. We put forward another kind of the non-planar ring lasers, in which the corner cube prism is the eye element. The non-planar traveling ray in the corner cube, Faraday rotation in the Nd:YAG crystal placed in a magnetic field and the different output coupling in S and P polarization can yield the single-frequency laser output in theory. The distorted Porro prism made by Nd:YAG crystal plays the role of the laser medium and the laser output coupler is realized by one of the two roof surfaces. The whole system can be made as a quasi-monolithic laser by optical bonding technology.

A coherent 1.06micrometers all solid state laser radar system is proposed. The system uses a LD pumped monolithic Nd:YAG ring laser as the source. Very stable output of the laser is linearly frequency modulated by an acousto-optic modulator. The wide modulation bandwidth is achieved by cascading two Bragg cells, in which each cell produces half of the total bandwidth. In order to extinguish the laser beam deflection caused by the Bragg cell, the propagation directions for the acoustic waves are arranged to be opposite in the two cells. Two single model optical fiber couplers are utilized. One is used as a beam splitter and divides the modulated laser beam into two parts: the transmitted signal beam and the local reference beam. The other coupler mixes the target-reflected signal beam with the local reference beam. The output signal form this coupler is detected by an InGaAs PIN photodiode, then analyzed by a RF electronic spectrum analyzer. The linearly frequency modulated CW ladar system can be applied for measuring both range and velocity of the target. Using this ladar system, true 3D target imaging can be achieved by additional use of a laser beam-scanning device.

Blood pressure is reportedly elevated in the spontaneously hypertensive rat (SHR) neonate, the etiology of which remains unclear. Aberrations in the hypothalamic-pituitary-adrenal axis have been implicated, as it is well accepted that excess corticosteroids are associated with hypertension. We examined aspects of adrenocortical activity in the neonatal SHR 1 to 21 days old and its normotensive genetic control, the Wistar-Kyoto rat (WKY). We found a fourfold greater abundance of P450scc mRNA in adrenals of SHR versus WKY day 1 neonates, and increasing but comparable abundance of adrenal P450c11B mRNA on neonatal days 1 to 21. The pattern of P450c11AS mRNA expression was distinctly different in the adrenals of SHR and WKY neonates; the relative abundance of this mRNA in SHR increased 15-fold over the 21-day period examined, whereas that in WKY remained fairly stable. RT-PCR for the presence/abundance of adrenal P450c11B3 mRNA showed absence in day 1 SHR and WKY, comparable abundances on neonatal days 7 and 14, and a distinctly greater abundance in the day 21 SHR adrenals. Peripheral corticosterone levels were threefold greater in the day 1 SHR neonate; aldosterone levels were elevated in both the SHR and WKY day 1 neonate. Thereafter, corticosterone and aldosterone levels were comparable on days 7, 14, and 21, although the anticipated depression in circulating corticosterone levels typical of the stress hyporesponsive period was noted in both SHR and WKY neonates. Although patterns of adrenocortical activity differ in the newborn SHR and WKY rat, our findings do not support an etiologic role for corticosteroids in the reported hypertension of the SHR. However, observed differences in corticosteroid profiles may augment or have a permissive effect upon the etiologic factor(s).

Archaea (archaebacteria) constitute one of the three major evolutionary lineages of life on Earth. Previously these prokaryotes were thought to predominate in only a few unusual and disparate niches, characterized by hypersaline, extremely hot, or strictly anoxic conditions. Recently, novel (uncultivated) phylotypes of Archaea have been detected in coastal and subsurface marine waters, but their abundance, distribution, physiology and ecology remain largely undescribed. Here we report exceptionally high archaeal abundance in frigid marine surface waters of Antarctica. Pelagic Archaea constituted up to 34% of the prokaryotic biomass in coastal Antarctic surface waters, and they were also abundant in a variety of other cold, pelagic marine environments. Because they can make up a significant fraction of picoplankton biomass in the vast habitats encompassed by cold and deep marine waters, these pelagic Archaea represent an unexpectedly abundant component of the Earth's biota.