Source-receptor relationships for PM2.5 during typical pollution episodes in the Pearl River Delta city cluster, China

NASA Astrophysics Data System (ADS)

Fan, Q.; Liu, Y.; Hong, Y.; Wang, X.; Chan, P.; Chen, X.; Lai, A.; Wang, M.; Chen, X.

2017-12-01

Located in the Southern China monsoon region, pollution days in Pearl River Delta (PRD) were classified into "Western type", "Central type" or "Eastern type", with a relative percentage of 67%, 24% and 9%, respectively. Using this classification system, three typical pollution events were selected for numerical simulations using the WRF-Chem model. The source sensitivity method for anthropogenic emissions of PM2.5 and its precursors was applied to identify the source-receptor relationships for PM2.5 among 9 cities in PRD. For "Western type" case, the PRD region was under control of a high-pressure system with easterly prevailing winds. The PM2.5 concentrations in the western PRD region were higher than those in the eastern region, with emissions from cities in the eastern PRD region having higher contributions. Within the PRD's urban cluster, PM2.5 in Huizhou, Dongguan and Shenzhen was mainly derived from local emissions, whereas the PM2.5 in the other cities was primarily derived from external transport. For "Eastern type" case, the PRD was influenced by Typhoon Soulik with westerly prevailing winds. Emissions from cities in the western PRD region had the highest impacts on the overall PM2.5 concentration. PM2.5 in Jiangmen and Foshan was primarily derived from local emissions. Regarding "Central type" case, the PRD region was under control of a uniform pressure field with low wind speed. PM2.5 concentrations of each city were primarily caused by local emissions. Overall, wind flows played a significant role in the transport and spatial distribution of PM2.5 across the PRD region. Ideally, local governments would be wise to establish joint prevention and control measures to reduce regional atmospheric pollution, especially for "Western type" pollution.

Mitochondrial DNA in Residual Leukemia Cells in Cerebrospinal Fluid in Children with Acute Lymphoblastic Leukemia

PubMed Central

Egan, Kathryn; Kusao, Ian; Troelstrup, David; Agsalda, Melissa; Shiramizu, Bruce

2010-01-01

This feasibility study was designed to assess the ability to measure mitochondrial DNA (mtDNA) in cerebrospinal fluid (CSF) cells that contributed to minimal disease/persistent or residual disease (MD/PRD) from children with acute lymphoblastic leukemia (ALL). Increase in mtDNA copies in cancer cells has been suggested to play a role in MD/PRD. CSF as well as blood specimens from 6 children were assayed for MD/PRD and mtDNA copy numbers by quantitative real-time polymerase chain reaction. Of 7 MD/PRD-positive specimens, 6 had increased mtDNA copy numbers; while 11 MD/PRD-negative specimens had no increase in mtDNA copy numbers, p < 0.003. This is the first proof-of-concept study to measure mtDNA copy numbers in MD/PRD-positive CSF specimens from children with ALL. Increase of mtDNA copy numbers in MD/PRD childhood ALL cells and its significance as a mechanism for recurrence requires further investigation. Keywords Minimal residual disease; Acute lymphoblastic leukemia; Central nervous system; Cerebrospinal fluid; Mitochondria PMID:21331151

Impact of xerostomia on dysphagia after chemotherapy-intensity-modulated radiotherapy for oropharyngeal cancer: Prospective longitudinal study.

PubMed

Vainshtein, Jeffrey M; Samuels, Stuart; Tao, Yebin; Lyden, Teresa; Haxer, Marc; Spector, Matthew; Schipper, Matthew; Eisbruch, Avraham

2016-04-01

The purpose of this study was to assess how xerostomia affects dysphagia. Prospective longitudinal studies of 93 patients with oropharyngeal cancer treated with definitive chemotherapy-intensity-modulated radiotherapy (IMRT). Observer-rated dysphagia (ORD), patient-reported dysphagia (PRD), and patient-reported xerostomia (PRX) assessment of the swallowing mechanics by videofluoroscopy (videofluoroscopy score), and salivary flow rates, were prospectively assessed from pretherapy through 2 years. ORD grades ≥2 were rare and therefore not modeled. Of patients with no/mild videofluoroscopy abnormalities, a substantial proportion had PRD that peaked 3 months posttherapy and subsequently improved. Through 2 years, highly significant correlations were observed between PRX and PRD scores for all patients, including those with no/mild videofluoroscopy abnormalities. Both PRX and videofluoroscopy scores were highly significantly associated with PRD. On multivariate analysis, PRX score was a stronger predictor of PRD than the videofluoroscopy score. Xerostomia contributes significantly to PRD. Efforts to further decrease xerostomia, in addition to sparing parotid glands, may translate into improvements in PRD. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1605-E1612, 2016. © 2015 Wiley Periodicals, Inc.

Corynebacterium godavarianum sp. nov., isolated from the Godavari river, India.

PubMed

Jani, Kunal; Khare, Kaustubh; Senik, Svetlana; Karodi, Prachi; Vemuluri, Venkata Ramana; Bandal, Jayashree; Shouche, Yogesh; Rale, Vinay; Sharma, Avinash

2018-01-01

A Gram-stain-positive, rod-shaped, non-motile bacterium, strain PRD07 T , was isolated from Godavari river, India during the world's largest spiritual and religious mass bathing event 'Kumbh Mela'. Molecular analysis using 16S rRNA gene sequencing and phylogenetic analysis reveals the distinct phylogenetic positioning of strain PRD07 T within the genus Corynebacterium. The strain demonstrated highest sequence similarity to Corynebacterium imitans DSM 44264 T (97.9 %), Corynebacterium appendicis DSM 44531 T (97.1 %) and <96.7 % with all other members of the genus Corynebacterium. The G+C content of PRD07 T was 68.5 mol% (Tm) and the DNA-DNA hybridization depicts 61.09 % genomic relatedness with C. imitans DSM 44264 T . Chemotaxonomic assessment of strain PRD07 T suggested presence of C16 : 0 (31.6 %), C18 : 0 (3.5 %) and C18 : 1ω9c (58.6 %) as the major cellular fatty acids. The major polar lipids of strain PRD07 T were phosphatidylglycerol, diphosphatidylglycerol and glycophospholipid. Differentiating molecular, phylogenetic and chemotaxonomic characteristics of strain PRD07 T with its closest relatives necessitated the description of strain PRD07 T as a novel species of genus Corynebacterium for which the name Corynebacteriumgodavarianum sp. nov., has been proposed. The type strain is PRD07 T (=MCC 3388 T =KCTC 39803 T =LMG 29598 T ).

Source-receptor relationships for PM2.5 during typical pollution episodes in the Pearl River Delta city cluster, China.

PubMed

Liu, Yiming; Hong, Yingying; Fan, Qi; Wang, Xuemei; Chan, Pakwai; Chen, Xiaoyang; Lai, Anqi; Wang, Mingjie; Chen, Xunlai

2017-10-15

Located in the Southern China monsoon region, pollution days in Pearl River Delta (PRD) were classified into "Western type", "Central type" or "Eastern type", with a relative percentage of 67%, 24% and 9%, respectively. Using this classification system, three typical pollution events were selected for numerical simulations using the WRF-Chem model. The source sensitivity method for anthropogenic emissions of PM 2.5 and its precursors was applied to identify the source-receptor relationships for PM 2.5 among 9 cities in PRD. For "Western type" case, the PRD region was under control of a high-pressure system with easterly prevailing winds. The PM 2.5 concentrations in the western PRD region were higher than those in the eastern region, with emissions from cities in the eastern PRD region having higher contributions. Within the PRD's urban cluster, PM 2.5 in Huizhou, Dongguan and Shenzhen was mainly derived from local emissions, whereas the PM 2.5 in the other cities was primarily derived from external transport. For "Eastern type" case, the PRD was influenced by Typhoon Soulik with westerly prevailing winds. Emissions from cities in the western PRD region had the highest impacts on the overall PM 2.5 concentration. PM 2.5 in Jiangmen and Foshan was primarily derived from local emissions. Regarding "Central type" case, the PRD region was under control of a uniform pressure field with low wind speed. PM 2.5 concentrations of each city were primarily caused by local emissions. Overall, wind flows played a significant role in the transport and spatial distribution of PM 2.5 across the PRD region. Ideally, local governments would be wise to establish joint prevention and control measures to reduce regional atmospheric pollution, especially for "Western type" pollution. Copyright © 2017 Elsevier B.V. All rights reserved.

period -1 encodes an ATP-dependent RNA helicase that influences nutritional compensation of the Neurospora circadian clock

DOE PAGES

Emerson, Jillian M.; Bartholomai, Bradley M.; Ringelberg, Carol S.; ...

2015-12-08

Mutants in the period-1 ( prd­-1) gene, characterized by a recessive allele, display a reduced growth rate and period lengthening of the developmental cycle controlled by the circadian clock. We refined the genetic location of prd­-1 and used whole genome sequencing to find the mutation defining it, confirming the identity of prd­-1 by rescuing the mutant circadian phenotype via transformation. PRD-1 is an RNA helicase whose orthologs, DDX5 and DDX17 in humans and Dbp2p in yeast, are implicated in various processes including transcriptional regulation, elongation, and termination, 23 ribosome biogenesis, and RNA decay. Although prd­-1smutantssiois an ATP-dependent RNA helicase, membermore » of a sub-family display a long period (~25 hrs) circadian developmental cycle, they interestingly display a wild type period when the core circadian oscillator is tracked using a frq-luciferase transcriptional fusion under conditions of limiting nutritional carbon; the core oscillator runs with a long period under glucose-sufficient conditions. Furthermore PRD-1 clearly impacts the circadian oscillator and is not only part of a metabolic oscillator ancillary to the core clock. PRD-1 is an essential protein and its expression is neither light-regulated nor clock-regulated. However, it is transiently induced by glucose; in the presence of sufficient glucose PRD-1 is in the nucleus until glucose runs out which elicits its disappearance from the nucleus. Because circadian period length is carbon concentration-dependent, prd­-1 may be formally viewed as clock mutant with defective nutritional compensation of circadian period length.« less

Flight service evaluation of PRD-49/epoxy composite panels in wide-bodied commercial transport aircraft

NASA Technical Reports Server (NTRS)

Wooley, J. H.

1974-01-01

Fairing panels were fabricated to evaluate the fabrication characteristics and flight service performance of PRD-49 (Kevlar-49) a composite reinforcing material and to compare it with the fiberglass which is currently in use. Panel configurations were selected to evaluate the PRD-49 with two resin matrix materials in sandwich and solid laminate construction. Left and right hand versions of these configurations were installed on L-1011's which will accumulate approximately 3000 flight hours per year per aircraft. The direct substitution of PRD-49 for fiberglass produced a twenty-six percent weight reduction on the panel configurations. Examination of these panels revealed that there was no visible difference between the PRD-49 and adjacent fiberglass panels.

Heavy metal(loid)s and organic contaminants in groundwater in the Pearl River Delta that has undergone three decades of urbanization and industrialization: Distributions, sources, and driving forces.

PubMed

Huang, Guanxing; Zhang, Ming; Liu, Chunyan; Li, Liangping; Chen, Zongyu

2018-09-01

Urbanization and industrialization have increased groundwater resource demands, and may drive the change of heavy metal(loid)s and organic chemicals in groundwater in the Pearl River Delta (PRD), southern China. Thus, a comprehensive understanding of the distributions, sources, and driving forces of heavy metal(loid)s and organic chemicals in groundwater in the PRD is vital for water resource management in this region. In this study, eight heavy metal(loid)s and fifty-five organic chemicals in groundwater across the PRD were investigated. The results show that undrinkable groundwater related to heavy metal(loid)s was mainly due to high concentrations of Fe (19.3%) and As (6.8%). Eighteen organic contaminants were detected in groundwater in the PRD, where the most frequently detected organic contaminant was naphthalene, and its detection rate was 2.51%. In 5.3% of all groundwater samples, one or more organic contaminants were found. All detected organic contaminants, except ones without allowable limits, in groundwater were at concentrations below allowable limits of China. The mean concentrations of heavy metal(loid)s in granular aquifers were higher than those in fissured and karst aquifers, especially for Fe and As. Except Se, the mean concentrations of other heavy metal(loid)s and the frequency of detection of organic contaminants in groundwater in urbanized and peri-urban areas were higher than those in non-urbanized areas, especially for Hg, Co, and organic contaminants. Fe, As, and Se in groundwater mainly originated from the release of Fe/As/Se rich sediments. The former two were driven by reduction reactions, while the latter was driven by oxidation resulting from the infiltration of NO 3 - . In contrast, other five heavy metal(loid)s and organic contaminants in groundwater mainly originated from the anthropogenic sources, such as the infiltration of industrial sewage. It is evident that urbanization and industrialization are two powerful driving forces for heavy metal(loid)s and organic contaminants in groundwater in the PRD. Copyright © 2018 Elsevier B.V. All rights reserved.

Pentoxifylline during steroid window phase at induction to remission increases apoptosis in childhood with acute lymphoblastic leukemia.

PubMed

Gonzalez-Ramella, O; Ortiz-Lazareno, P C; Jiménez-López, X; Gallegos-Castorena, S; Hernández-Flores, G; Medina-Barajas, F; Meza-Arroyo, J; Jave-Suárez, L F; Lerma-Díaz, J M; Sánchez-Zubieta, F; Bravo-Cuellar, A

2016-04-01

Pentoxifylline (PTX) has been shown to increase chemotherapy-induced apoptosis. A clinical trial was developed to evaluate the effect of the addition of PTX to the induction steroid window phase in children with acute lymphoblastic leukemia (ALL). Thirty-two children were enrolled on this study. Children with a new diagnosis of ALL were randomly assigned to receive prednisone (PRD) 40 mg/m(2)/day only during the 7-day treatment pre-phase (PRD group, 11 patients) or to receive PRD with PTX (10 mg/kg/day) (PTX group, 11 patients); the control group included children with normal bone marrow (10 patients). Bone marrow aspiration (BMA) was performed at diagnosis (day -7) in all groups, and at day 0 (end of PRD window) for patients with ALL (PRD and PTX groups). Apoptosis was evaluated by flow cytometry (FC) using Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) stains. Statistical analysis was performed using the Mann-Whitney U test. Apoptotic index at day -7 was similar in all groups. However, at day 0 post-treatment, apoptosis was significantly higher in the PTX group than in the PRD group (p < 0.001). There were no serious adverse effects associated with PTX. PTX potentiates blast apoptosis induced by PRD in children with ALL during steroid window phase.

Enhancement in secondary particulate matter production due to mountain trapping

NASA Astrophysics Data System (ADS)

Yao, Teng; Fung, J. C. H.; Ma, H.; Lau, A. K. H.; Chan, P. W.; Yu, J. Z.; Xue, J.

2014-10-01

As China's largest economic development zone, the Pearl River Delta (PRD) is subject to particulate matter (PM) and visibility deterioration problems. Due to high PM concentration, haze days impacting ambient visibility have occurred frequently in this region. Besides visibility impairment, PM pollution also causes a negative impact on public health. These negative impacts have heightened the need to improve our understanding of the PM pollution of the PRD region. One major cause of the PRD pollution problem is cold front passages in the winter; however, the mechanism of pollution formation stays unclear. In this study, the Comprehensive Air Quality Model (CAMx) is utilized to investigate the detailed PM production and transport mechanisms in the PRD. Simulated concentrations of PM2.5 species, which have a good correlation with observation, show that sulfate and nitrate are the dominant pollutants among different PM2.5 species. Before the cold front passage a large amount of gas-phase and particle-phase pollutants are transported to the mountainous regions in the north of the PRD, and become trapped by the terrain. Over the mountain regions, cloud driven by upwelling flow promotes aqueous-phase reactions including oxidations of PM precursors such as SO2 and NO2. By this process, production of secondary PM is enhanced. When the cold front continues to advance further south, PM is transported to the PRD cities, and suppressed into a thin layer near the ground by a low planetary boundary layer (PBL). Thus high PM concentration episodes take place in the PRD cities. After examining production and transportation pathways, this study presents that the complex terrain configuration would block pollutant dispersion, provide cloudy environment, and advance secondary PM production. Previous studies have pointed out that pollution emitted from outside this region largely influences the air quality in the PRD; however, this study shows that pollutants from the outside could be originated from the PRD and transported back resulting in significant increase of secondary PM concentration, and provides new insight into PM production and transport mechanism in the PRD.

Monitoring and Analyzing the Geospatial Patterns of the Pearl River Delta (prd) from 1960 TO 2012

NASA Astrophysics Data System (ADS)

Wang, J.; Wu, Z.; Li, S.; Cao, Z.

2018-04-01

The Geospatial Patterns Pearl River Delta (PRD), one of the most economically-important and fastest-growing regions in China, have changed remarkably and continuously during the past decades. In this research, the change of landuse, coastline during 1960-2012 were closely investigated to provide better description and explanation of the geospatial pattern. And the relationships between them were explored. Finally, the impact that urban expansion brought to the coastal environment was quantitatively analyzed. The main remarks of this research are summarized into the following points: (1) In PRD, construction land expanded 33 times. In the meantime, the area of forest and farmland decreased 47.53 % and 56.70 %, respectively. (2) The land demand for agricultural development was the key factor that changed coastline in PRD before 2000. Since 2000, land demand for urban construction has been the key factor that changed coastline in PRD. (3) During 1960 to 2012, the length of coastline in PRD increased from 1134.95 km to 1508.02 km with an increasing speed of 7.17 km per year. Relatively, the coastline changed more obvious in three periods (2004 to 2006, 2006 to 2008 and 2008 to 2010). (4) The type of coastline changed remarkably from 1960 to 2012. 82.94 % of the natural coastline in PRD disappeared until 2012. Known from this research, the geospatial patterns of the PRD changed remarkably during 1960 to 2012, mainly driven by human activities. The coastal environment is facing serious risks and challenges under the rapid process of urbanization.

period -1 encodes an ATP-dependent RNA helicase that influences nutritional compensation of the Neurospora circadian clock

DOE Office of Scientific and Technical Information (OSTI.GOV)

Emerson, Jillian M.; Bartholomai, Bradley M.; Ringelberg, Carol S.

Mutants in the period-1 (prd-1) gene, characterized by a recessive allele, display a reduced growth rate and period lengthening of the developmental cycle controlled by the circadian clock. We refined the genetic location of prd-1 and used whole genome sequencing to find the mutation defining it, confirming the identity of prd-1 by rescuing the mutant circadian phenotype via transformation. PRD-1 is an RNA helicase whose orthologs, DDX5 and DDX17 in humans and Dbp2p in yeast, are implicated in various processes including transcriptional regulation, elongation, and termination, 23 ribosome biogenesis, and RNA decay. Although prdi-1smutantssiois an ATP-dependent RNA helicase, member ofmore » a sub-family display a long period (~25 hrs) circadian developmental cycle, they interestingly display a wild type period when the core circadian oscillator is tracked using a frq-luciferase transcriptional fusion under conditions of limiting nutritional carbon; the core oscillator runs with a long period under glucose-sufficient conditions. Thus PRD-1 clearly impacts the circadian oscillator and is not only part of a metabolic oscillator ancillary to the core clock. PRD-1 is an essential protein and its expression is neither light-regulated nor clock-regulated. However, it is transiently induced by glucose; in the presence of sufficient glucose PRD-1 is in the nucleus until glucose runs out which elicits its disappearance from the nucleus. Because circadian period length is carbon concentration-dependent, prd­-1 may be formally viewed as clock mutant with defective nutritional compensation of circadian period length.« less

period -1 encodes an ATP-dependent RNA helicase that influences nutritional compensation of the Neurospora circadian clock

DOE Office of Scientific and Technical Information (OSTI.GOV)

Emerson, Jillian M.; Bartholomai, Bradley M.; Ringelberg, Carol S.

2015-12-08

Mutants in the period-1 (prd-1) gene, characterized by a recessive allele, display a reduced growth rate and period lengthening of the developmental cycle controlled by the circadian clock. We refined the genetic location of prd-1 and used whole genome sequencing to find the mutation defining it, confirming the identity of prd-1 by rescuing the mutant circadian phenotype via transformation. PRD-1 is an RNA helicase whose orthologs, DDX5 and DDX17 in humans and Dbp2p in yeast, are implicated in various processes including transcriptional regulation, elongation, and termination, 23 ribosome biogenesis, and RNA decay. Although prdi-1smutantssiois an ATP-dependent RNA helicase, member ofmore » a sub-family display a long period (~25 hrs) circadian developmental cycle, they interestingly display a wild type period when the core circadian oscillator is tracked using a frq-luciferase transcriptional fusion under conditions of limiting nutritional carbon; the core oscillator runs with a long period under glucose-sufficient conditions. Thus PRD-1 clearly impacts the circadian oscillator and is not only part of a metabolic oscillator ancillary to the core clock. PRD-1 is an essential protein and its expression is neither light-regulated nor clock-regulated. However, it is transiently induced by glucose; in the presence of sufficient glucose PRD-1 is in the nucleus until glucose runs out which elicits its disappearance from the nucleus. Because circadian period length is carbon concentration-dependent, prd­-1 may be formally viewed as clock mutant with defective nutritional compensation of circadian period length.« less

Developing chemical signatures of particulate air pollution in the Pearl River Delta region, China.

PubMed

Zheng, Mei; Cheng, Yuan; Zeng, Limin; Zhang, Yuanhang

2011-01-01

PM2.5 samples were collected in a regional sampling network with three sites in Hong Kong and four sites in the adjacent inland Pearl River Delta (PRD) or Guangdong Province during four months/seasons from 2002-2003. Trans-boundary transport between Hong Kong and the inland PRD is inevitable under the influence of Asian monsoon. In summer, Hong Kong serves as the upwind site of the inland PRD while during other seasons it is under the influence of continental emissions. Previous studies have recognized the importance of using chemical signatures to differentiate local vs. regional contributions to air pollutants in Hong Kong such as the CO/NOx ratio, ratios of different VOC species. In this study, detailed chemical speciation by gas chromatography-mass spectrometry was performed with PM2.5 samples to identify new chemical signatures to distinguish aerosols in Hong Kong from those from the inland PRD. Since Hong Kong is not influenced by the continental emissions from the inland PRD during summer, comparison focused on chemical data obtained from this season for chemical signatures. The new ratios developed from the current study include LCPI/HCPI ratio of alkanes (0.39 +/- 0.02 in Hong Kong vs. 0.78 +/- 0.08 in the inland PRD), pyrene to benzo[ghi]perylene ratio (0.97 +/- 0.21 in Hong Kong compared to 0.20 +/- 0.06 in the inland PRD), and the ratio of 1,2-benzenedioic acid to 1,4-benzenedioic acid (1.8 +/- 0.1 in Hong Kong vs. 0.6 +/- 0.05 in the inland PRD). Results from this study also revealed that Hong Kong was impacted by ship emissions as reflected by substantially high V/Ni ratio (9 +/- 2) while this ratio was about 1-2 at all sites in the inland PRD, which is very close to typical ratios from residual oil combustion.

Effect of goethite coating and humic acid on the transport of bacteriophage PRD1 in columns of saturated sand

NASA Astrophysics Data System (ADS)

Foppen, J. W. A.; Okletey, S.; Schijven, J. F.

2006-05-01

The transport of bacteriophage PRD1, a model virus, was studied in columns containing sediment mixtures of quartz sand with goethite-coated sand and using various solutions consisting of monovalent and divalent salts and humic acid (HA). Without HA and in the absence of sand, the inactivation rate of PRD1 was found to be as low as 0.014 day - 1 (at 5 ± 3 °C), but in the presence of HA it was much lower (0.0009 day - 1 ), indicating that HA helps PRD1 to survive. When the fraction of goethite in the sediment was increased, the removal of PRD1 also increased. However, in the presence of HA, C/ C0 values of PRD1 increased by as much as 5 log units, thereby almost completely eliminating the effect of addition of goethite. The sticking efficiency was not linearly dependent on the amount of goethite added to the quartz sand; this is apparently due to surface charge heterogeneity of PRD1. Our results imply that, in the presence of dissolved organic matter (DOM), viruses can be transported for long distances thanks to two effects: attachment is poor because DOM has occupied favourable sites for attachment and inactivation of virus may have decreased. This conclusion justifies making conservative assumptions about the attachment of viruses when calculating protection zones for groundwater wells.

A field study of virus removal in septic tank drainfields.

PubMed

Nicosia, L A; Rose, J B; Stark, L; Stewart, M T

2001-01-01

Two field studies were conducted at a research station in Tampa, Florida to assess the removal of bacteriophage PRD1 from wastewater in septic tank drainfields. Infiltration cells were seeded with PRD1 and bromide and the effects of effluent hydraulic loading rate and rainfall on virus removal were monitored. Septic tank effluent samples were collected after passage through 0.6 m of unsaturated fine sand and PRD1 was detected over an average of 67 d. Bacteriophage PRD1 breakthrough was detected at approximately the same time as bromide in all three cells except for the low-load cell (Study 1), where bromide was never detected. Log10 removals of PRD1 were 1.43 and 1.91 for the high-load cells (hydraulic loading rate = 0.063 m/d) and 2.21 for the low-load cell (hydraulic loading rate = 0.032 m/d). Virus attenuation is attributed to dispersion, dilution, and inactivation. Significant increases in PRD1 elution with rainfall were observed in the first 10 d of the study. Approximately 125 mm of rainfall caused a 1.2 log10 increase of PRD1 detected at the 0.6-m depth. Current Florida onsite wastewater disposal standards, which specify a 0.6-m distance from the drainfield to the water table, may not provide sufficient removal of viruses, particularly during the wet season.

Contrasting physiological effects of partial root zone drying in field-grown grapevine (Vitis vinifera L. cv. Monastrell) according to total soil water availability

PubMed Central

Romero, Pascual; Dodd, Ian C.; Martinez-Cutillas, Adrian

2012-01-01

Different spatial distributions of soil moisture were imposed on field-grown grapevines by applying the same irrigation volumes to the entire (DI; deficit irrigation) or part of the (PRD; partial root zone drying) root zone. Five treatments were applied: controls irrigated at 60% ETc (crop evapotranspiration) for the whole season (308 mm year−1); DI-1 and PRD-1 that received the same irrigation as controls before fruit set, 30% ETc from fruit set to harvest and 45% ETc post-harvest (192 mm year−1); and DI-2 and PRD-2 that were the same, except that 15% ETc was applied from fruit set to harvest (142 mm year−1). Compared with DI-1, PRD-1 maintained higher leaf area post-veraison and increased root water uptake, whole-plant hydraulic conductance, leaf transpiration, stomatal conductance, and photosynthesis, but decreased intrinsic gas exchange efficiency without causing differences in leaf xylem abscisic acid (ABA) concentration. Compared with DI-2, PRD-2 increased leaf xylem ABA concentration and decreased root water uptake, whole-plant hydraulic conductance, leaf transpiration, stomatal conductance, and photosynthesis, mainly at the beginning of PRD cycles. Distinctive PRD effects (e.g. greater stomatal closure) depended on the volumetric soil water content of the wet root zone, as predicted from a model of root-to-shoot ABA signalling. PMID:22451721

Antisense RNA Strategies for Metabolic Engineering of Clostridium acetobutylicum

PubMed Central

Desai, Ruchir P.; Papoutsakis, Eleftherios T.

1999-01-01

We examined the effectiveness of antisense RNA (as RNA) strategies for metabolic engineering of Clostridium acetobutylicum. Strain ATCC 824(pRD4) was developed to produce a 102-nucleotide asRNA with 87% complementarity to the butyrate kinase (BK) gene. Strain ATCC 824(pRD4) exhibited 85 to 90% lower BK and acetate kinase specific activities than the control strain. Strain ATCC 824(pRD4) also exhibited 45 to 50% lower phosphotransbutyrylase (PTB) and phosphotransacetylase specific activities than the control strain. This strain exhibited earlier induction of solventogenesis, which resulted in 50 and 35% higher final concentrations of acetone and butanol, respectively, than the concentrations in the control. Strain ATCC 824(pRD1) was developed to putatively produce a 698-nucleotide asRNA with 96% complementarity to the PTB gene. Strain ATCC 824(pRD1) exhibited 70 and 80% lower PTB and BK activities, respectively, than the control exhibited. It also exhibited 300% higher levels of a lactate dehydrogenase activity than the control exhibited. The growth yields of ATCC 824(pRD1) were 28% less than the growth yields of the control. While the levels of acids were not affected in ATCC 824(pRD1) fermentations, the acetone and butanol concentrations were 96 and 75% lower, respectively, than the concentrations in the control fermentations. The lower level of solvent production by ATCC 824(pRD1) was compensated for by ∼100-fold higher levels of lactate production. The lack of any significant impact on butyrate formation fluxes by the lower PTB and BK levels suggests that butyrate formation fluxes are not controlled by the levels of the butyrate formation enzymes. PMID:10049845

Antisense RNA strategies for metabolic engineering of Clostridium acetobutylicum.

PubMed

Desai, R P; Papoutsakis, E T

1999-03-01

We examined the effectiveness of antisense RNA (as RNA) strategies for metabolic engineering of Clostridium acetobutylicum. Strain ATCC 824(pRD4) was developed to produce a 102-nucleotide asRNA with 87% complementarity to the butyrate kinase (BK) gene. Strain ATCC 824(pRD4) exhibited 85 to 90% lower BK and acetate kinase specific activities than the control strain. Strain ATCC 824(pRD4) also exhibited 45 to 50% lower phosphotransbutyrylase (PTB) and phosphotransacetylase specific activities than the control strain. This strain exhibited earlier induction of solventogenesis, which resulted in 50 and 35% higher final concentrations of acetone and butanol, respectively, than the concentrations in the control. Strain ATCC 824(pRD1) was developed to putatively produce a 698-nucleotide asRNA with 96% complementarity to the PTB gene. Strain ATCC 824(pRD1) exhibited 70 and 80% lower PTB and BK activities, respectively, than the control exhibited. It also exhibited 300% higher levels of a lactate dehydrogenase activity than the control exhibited. The growth yields of ATCC 824(pRD1) were 28% less than the growth yields of the control. While the levels of acids were not affected in ATCC 824(pRD1) fermentations, the acetone and butanol concentrations were 96 and 75% lower, respectively, than the concentrations in the control fermentations. The lower level of solvent production by ATCC 824(pRD1) was compensated for by approximately 100-fold higher levels of lactate production. The lack of any significant impact on butyrate formation fluxes by the lower PTB and BK levels suggests that butyrate formation fluxes are not controlled by the levels of the butyrate formation enzymes.

The structure of the bacteriophage PRD1 spike sheds light on the evolution of viral capsid architecture.

PubMed

Merckel, Michael C; Huiskonen, Juha T; Bamford, Dennis H; Goldman, Adrian; Tuma, Roman

2005-04-15

Comparisons of bacteriophage PRD1 and adenovirus protein structures and virion architectures have been instrumental in unraveling an evolutionary relationship and have led to a proposal of a phylogeny-based virus classification. The structure of the PRD1 spike protein P5 provides further insight into the evolution of viral proteins. The crystallized P5 fragment comprises two structural domains: a globular knob and a fibrous shaft. The head folds into a ten-stranded jelly roll beta barrel, which is structurally related to the tumor necrosis factor (TNF) and the PRD1 coat protein domains. The shaft domain is a structural counterpart to the adenovirus spike shaft. The structural relationships between PRD1, TNF, and adenovirus proteins suggest that the vertex proteins may have originated from an ancestral TNF-like jelly roll coat protein via a combination of gene duplication and deletion.

Computational Tools to Assess Turbine Biological Performance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Richmond, Marshall C.; Serkowski, John A.; Rakowski, Cynthia L.

2014-07-24

Public Utility District No. 2 of Grant County (GCPUD) operates the Priest Rapids Dam (PRD), a hydroelectric facility on the Columbia River in Washington State. The dam contains 10 Kaplan-type turbine units that are now more than 50 years old. Plans are underway to refit these aging turbines with new runners. The Columbia River at PRD is a migratory pathway for several species of juvenile and adult salmonids, so passage of fish through the dam is a major consideration when upgrading the turbines. In this paper, a method for turbine biological performance assessment (BioPA) is demonstrated. Using this method, amore » suite of biological performance indicators is computed based on simulated data from a CFD model of a proposed turbine design. Each performance indicator is a measure of the probability of exposure to a certain dose of an injury mechanism. Using known relationships between the dose of an injury mechanism and frequency of injury (dose–response) from laboratory or field studies, the likelihood of fish injury for a turbine design can be computed from the performance indicator. By comparing the values of the indicators from proposed designs, the engineer can identify the more-promising alternatives. We present an application of the BioPA method for baseline risk assessment calculations for the existing Kaplan turbines at PRD that will be used as the minimum biological performance that a proposed new design must achieve.« less

On the extraordinary strength of Prince Rupert's drops

NASA Astrophysics Data System (ADS)

Aben, H.; Anton, J.; Öis, M.; Viswanathan, K.; Chandrasekar, S.; Chaudhri, M. M.

2016-12-01

Prince Rupert's drops (PRDs), also known as Batavian tears, have been in existence since the early 17th century. They are made of a silicate glass of a high thermal expansion coefficient and have the shape of a tadpole. Typically, the diameter of the head of a PRD is in the range of 5-15 mm and that of the tail is 0.5 to 3.0 mm. PRDs have exceptional strength properties: the head of a PRD can withstand impact with a small hammer, or compression between tungsten carbide platens to high loads of ˜15 000 N, but the tail can be broken with just finger pressure leading to catastrophic disintegration of the PRD. We show here that the high strength of a PRD comes from large surface compressive stresses in the range of 400-700 MPa, determined using techniques of integrated photoelasticity. The surface compressive stresses can suppress Hertzian cone cracking during impact with a small hammer or compression between platens. Finally, it is argued that when the compressive force on a PRD is very high, plasticity in the PRD occurs, which leads to its eventual destruction with increasing load.

Predicting self-rated mental and physical health: the contributions of subjective socioeconomic status and personal relative deprivation

PubMed Central

Callan, Mitchell J.; Kim, Hyunji; Matthews, William J.

2015-01-01

Lower subjective socioeconomic status (SSS) and higher personal relative deprivation (PRD) relate to poorer health. Both constructs concern people's perceived relative social position, but they differ in their emphasis on the reference groups people use to determine their comparative disadvantage (national population vs. similar others) and the importance of resentment that may arise from such adverse comparisons. We investigated the relative utility of SSS and PRD as predictors of self-rated physical and mental health (e.g., self-rated health, stress, health complaints). Across six studies, self-rated physical and mental health were on the whole better predicted by measures of PRD than by SSS while controlling for objective socioeconomic status (SES), with SSS rarely contributing unique variance over and above PRD and SES. Studies 4–6 discount the possibility that the superiority of PRD over SSS in predicting health is due to psychometric differences (e.g., reliability) or response biases between the measures. PMID:26441786

Social comparison, personal relative deprivation, and materialism.

PubMed

Kim, Hyunji; Callan, Mitchell J; Gheorghiu, Ana I; Matthews, William J

2017-06-01

Across five studies, we found consistent evidence for the idea that personal relative deprivation (PRD), which refers to resentment stemming from the belief that one is deprived of deserved outcomes compared to others, uniquely contributes to materialism. In Study 1, self-reports of PRD positively predicted materialistic values over and above socioeconomic status, personal power, self-esteem, and emotional uncertainty. The experience of PRD starts with social comparison, and Studies 2 and 3 found that PRD mediated the positive relation between a tendency to make social comparisons of abilities and materialism. In Study 4, participants who learned that they had less (vs. similar) discretionary income than people like them reported a stronger desire for more money relative to donating more to charity. In Study 5, during a windfall-spending task, participants higher in PRD spent more on things they wanted relative to other spending categories (e.g., paying off debts). © 2016 The Authors. British Journal of Social Psychology published by John Wiley & Sons Ltd on behalf of British Psychological Society.

Emergence of late-onset placental dysfunction: relationship to the change in uterine artery blood flow resistance between the first and third trimesters.

PubMed

Llurba, Elisa; Turan, Ozhan; Kasdaglis, Tania; Harman, Chris R; Baschat, Ahmet A

2013-06-01

To test if emergence of third-trimester (T3) placental dysfunction is related to the impedance change in uterine artery blood flow resistance between the first trimester (T1) and T3. Mean T1 and T3 uterine artery (mUtA) pulsatility index (PI) was measured in 1098 singletons. Each patient's individual mUtA-PI change was calculated ([(T3 PI - T1 PI/interval in days)] × 100; ΔmUtA-PI). This parameter and T1 and T3 mUtA-PI z-scores were related to placenta-related disease (PRD) and to constitutionally small neonates (CS). Forty-seven (5%) women had PRD and 83 (8.7%) delivered a CS neonate. T1 and T3 mUtA-PI z-scores were higher with PRD (0.418 versus -0.097 and 1.06 versus -0.13, p < 0.001 for all). Change in mUtA-PI (ΔmUtA PI) was similar for patients with PRD. However, the prevalence of PRD doubled with rising ΔmUtA-PI (11.1% versus 5.2%, p = 0.041). T3 uterine artery Doppler performs significantly better in detecting patients at risk for late-onset PRD than T1 or the gestational age change in uterine artery Doppler resistance This suggests that a proportion of late emerging PRD is not amenable to early screening by uterine artery Doppler. Further research is essential to identify the optimal screening strategy for late-onset placental dysfunction. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Influence of plant water status on the production of C13-norisoprenoid precursors in Vitis vinifera L. Cv. cabernet sauvignon grape berries.

PubMed

Bindon, Keren A; Dry, Peter R; Loveys, Brian R

2007-05-30

The influence of irrigation strategy on grape berry carotenoids and C13-norisoprenoid precursors was investigated for Vitis vinifera L. cv. Cabernet Sauvignon. Two irrigation treatments were compared, one in which vines received reduced irrigation applied alternately to either side of the vine (partial rootzone drying, PRD) and a second control treatment in which water was applied to both sides of the vine. Over the two years of the experiments, PRD vines received on average 66% of the water applied to the controls. Initially, the PRD treatment did not alter midday leaf (psiL) and stem (psiS) water potential relative to the control, but decreased stomatal conductance (gs). Continued exposure to the PRD treatment resulted in treated grapevines experiencing hydraulic water deficit relative to the control treatment and induced lowered midday psiL and psiS, which was also reflected in decreased berry weight at harvest. In both irrigation treatments, the most abundant grape berry carotenoids, beta-carotene and lutein, followed the developmental pattern typical of other grape varieties, decreasing post-veraison. At certain points in time, as the fruit approached maturity, the concentration of these carotenoids was increased in fruit of PRD-treated vines relative to the controls. This effect was greater for lutein than for beta-carotene. PRD consistently caused increases in the concentration of hydrolytically released C13-norisoprenoids beta-damascenone, beta-ionone, and 1,1,6-trimethyl-1,2-dihydronaphthalene in fruit at harvest (24 degrees Brix) over two seasons. The effect of the PRD treatment on the concentration of hydrolytically released C13-norisoprenoids was greater in the second of the two seasons of the experiment and was also reflected in an increase in total C13-norisoprenoid content per berry. This suggests that the increases in the concentration of the C13-norisoprenoids in response to PRD were independent of water deficit induced changes in berry size and were not the result of an altered berry surface area to volume ratio.

Magneto-optical Effects in the Scattering Polarization Wings of the Ca I 4227 Å Resonance Line

NASA Astrophysics Data System (ADS)

Alsina Ballester, E.; Belluzzi, L.; Trujillo Bueno, J.

2018-02-01

The linear polarization pattern produced by scattering processes in the Ca I 4227 Å resonance line is a valuable observable for probing the solar atmosphere. Via the Hanle effect, the very significant Q/I and U/I line-center signals are sensitive to the presence of magnetic fields in the lower chromosphere with strengths between 5 and 125 G, approximately. On the other hand, partial frequency redistribution (PRD) produces sizable signals in the wings of the Q/I profile, which have always been thought to be insensitive to the presence of magnetic fields. Interestingly, novel observations of this line revealed a surprising behavior: fully unexpected signals in the wings of the U/I profile and spatial variability in the wings of both Q/I and U/I. We show that the magneto-optical (MO) terms of the Stokes-vector transfer equation produce sizable signals in the wings of U/I and a clear sensitivity of the Q/I and U/I wings to the presence of photospheric magnetic fields with strengths similar to those that produce the Hanle effect in the line core. This radiative transfer investigation on the joint action of scattering processes and the Hanle and Zeeman effects in the Ca I 4227 Å line should facilitate the development of more reliable techniques for exploring the magnetism of stellar atmospheres. To this end, we can now exploit the circular polarization produced by the Zeeman effect, the magnetic sensitivity caused by the above-mentioned MO effects in the Q/I and U/I wings, and the Hanle effect in the line core.

Influence of water chemistry and travel distance on bacteriophage PRD-1 transport in a sandy aquifer

USGS Publications Warehouse

Blanford, W.J.; Brusseau, M.L.; Jim Yeh, T.-C.; Gerba, C.P.; Harvey, R.

2005-01-01

Experiments were conducted to evaluate the impact of groundwater chemistry and travel distance on the transport and fate behavior of PRD-1, a bacteriophage employed as a surrogate tracer for pathogenic enteric viruses. The experiments were conducted in the unconfined aquifer at the United States Geological Survey Cape Cod Toxic-Substances Hydrology Research Site in Falmouth, Massachusetts. The transport behavior of bromide (Br-) and PRD-1 were evaluated in a sewage-effluent contaminated zone and a shallower uncontaminated zone at this site. Several multilevel sampling devices located along a 13-m transect were used to collect vertically discrete samples to examine longitudinal and vertical variability of PRD-1 retardation and attenuation. The concentration of viable bacteriophage in the aqueous phase decreased greatly during the first few meters of transport. This decrease is attributed to a combination of colloid filtration (attachment) and inactivation. The removal was greater (10 -12 relative recovery) and occurred within the first meter for the uncontaminated zone, whereas it was lesser (10-9 relative recovery) and occurred over 4 m in the contaminated zone. The lesser removal observed for the contaminated zone is attributed to the influence of sorbed and dissolved organic matter, phosphate, and other anions, which are present in higher concentrations in the contaminated zone, on PRD-1 attachment. After the initial decrease, the aqueous PRD-1 concentrations remained essentially constant in both zones for the remainder of the tests (total travel distances of 13 m), irrespective of variations in geochemical properties within and between the two zones. The viable, mobile PRD-1 particles traveled at nearly the rate of bromide, which was used as a non-reactive tracer. The results of this study indicate that a small fraction of viable virus particles may persist in the aqueous phase and travel significant distances in the subsurface environment. ?? 2005 Elsevier Ltd. All rights reserved.

Use of PRD1 bacteriophage in groundwater viral transport, inactivation, and attachment studies

USGS Publications Warehouse

Harvey, Ronald W.; Ryan, Joseph N.

2004-01-01

PRD1, an icosahedra-shaped, 62 nm (diameter), double-stranded DNA bacteriophage with an internal membrane, has emerged as an important model virus for studying the manner in which microorganisms are transported through a variety of groundwater environments. The popularity of this phage for use in transport studies involving geologic media is due, in part, to its relative stability over a range of temperatures and low degree of attachment in aquifer sediments. Laboratory and field investigations employing PRD1 are leading to a better understanding of viral attachment and transport behaviors in saturated geologic media and to improved methods for describing mathematically subsurface microbial transport at environmentally significant field scales. Radioisotopic labeling of PRD1 is facilitating additional information about the nature of viral interactions with solid surfaces in geologic media, the importance of iron oxide surfaces, and allowing differentiation between inactivation and attachment in field-scale tracer tests.

Physiological and gene expression responses of sunflower (Helianthus annuus L.) plants differ according to irrigation placement.

PubMed

Aguado, Ana; Capote, Nieves; Romero, Fernando; Dodd, Ian C; Colmenero-Flores, José M

2014-10-01

To investigate effects of soil moisture heterogeneity on plant physiology and gene expression in roots and leaves, three treatments were implemented in sunflower plants growing with roots split between two compartments: a control (C) treatment supplying 100% of plant evapotranspiration, and two treatments receiving 50% of plant evapotranspiration, either evenly distributed to both compartments (deficit irrigation - DI) or unevenly distributed to ensure distinct wet and dry compartments (partial rootzone drying - PRD). Plants receiving the same amount of water responded differently under the two irrigation systems. After 3 days, evapotranspiration was similar in C and DI, but 20% less in PRD, concomitant with decreased leaf water potential (Ψleaf) and increased leaf xylem ABA concentration. Six water-stress responsive genes were highly induced in roots growing in the drying soil compartment of PRD plants, and their expression was best correlated with local soil water content. On the other hand, foliar gene expression differed significantly from that of the root and correlated better with xylem ABA concentration and Ψleaf. While the PRD irrigation strategy triggered stronger physiological and molecular responses, suggesting a more intense and systemic stress reaction due to local dehydration of the dry compartment of PRD plants, the DI strategy resulted in similar water savings without strongly inducing these responses. Correlating physiological and molecular responses in PRD/DI plants may provide insights into the severity and location of water deficits and may enable a better understanding of long-distance signalling mechanisms. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Impacts of urbanization on nitrogen deposition in the Pearl River Delta region, China

NASA Astrophysics Data System (ADS)

Wang, X.; Fan, Q.

2015-12-01

The Pearl River Delta (PRD) region is one of the most advanced economic districts in China, which has experienced remarkable economic development and urbanization in the past two decades. Accompanied with the rapid economy development and urbanization, the PRD region encountered both severe nitrogen pollution and deposition. In this study, the characteristics of nitrogen deposition and impacts of urbanization on nitrogen deposition in the PRD region were investigated by combining the methods of field study and numerical model. According to the field measurements, the total dry and wet atmospheric deposition of reactive N at a urban site (SYSU) was up to 55.0 kg ha-1 yr-1 in 2010, slightly lower than the results at a rural forest site (DHS) (57.6 kg ha-1 yr-1). Wet deposition was the main form of the total deposition (64-76%). Organic nitrogen (ON) was found to be dominant in the total N deposition, with a contribution of 53% at DHS and 42% at SYSU. NH4+-N and NO3--N accounted for a similar portion of the total N deposition (23-29%). Atmospheric nitrogen deposition was further simulated by using the improved WRF-Chem model. The simulated N deposition flux was high in the north of PRD (i.e., Guangzhou, Foshan, Zhaoqing) and relative low in the east (Huizhou) and south (Zhuhai), with an average N deposition flux of about 24 kg ha-1 yr-1 for the whole PRD. The distribution of N dry deposition was mainly controlled by the concentration of reactive N compounds and precipitation governed the wet deposition distribution. The modeling results also indicate that the PRD area is the source region in which the emissions exceed the deposition while the outside area of the PRD is the receptor region in which the deposition exceeds emissions. The impact of emission change and land use change due to urbanization was also investigated using the WRF-Chem model. The results showed that atmospheric N deposition exhibits a direct response to emission change while the land use change impacts the atmospheric N deposition indirectly mainly through the modification of precipitation. As a result of great challenges in reduction of the reactive N emission, a scenario of rising N deposition in the PRD cannot be discarded in the future.

Attribution of nitrogen deposition driven by urbanization over Pearl River Delta region China

NASA Astrophysics Data System (ADS)

Wang, X.; Wu, Z.

2016-12-01

The Pearl River Delta (PRD) region is one of the most advanced economic districts in China, which has experienced remarkable economic development and urbanization in the past two decades. Accompanied with the rapid economy development and urbanization, the PRD region encountered both severe nitrogen pollution and deposition. In this study, the characteristics of nitrogen deposition and impacts of urbanization on nitrogen deposition in the PRD region were investigated by combining the methods of field study and numerical model. According to the field measurements, the total dry and wet atmospheric deposition of reactive N at a urban site (SYSU) was up to 55.0 kg ha-1 yr-1 in 2010, slightly lower than the results at a rural forest site (DHS) (57.6 kg ha-1 yr-1). Wet deposition was the main form of the total deposition (64-76%). Organic nitrogen (ON) was found to be dominant in the total N deposition, with a contribution of 53% at DHS and 42% at SYSU. NH4+-N and NO3-N accounted for a similar portion of the total N deposition (23-29%). Atmospheric nitrogen deposition was further simulated by using the improved WRF-Chem model. The simulated N deposition flux was high in the north of PRD (i.e.,Guangzhou, Foshan, Zhaoqing) and relative low in the east (Huizhou) and south (Zhuhai), with an average N deposition flux of about 24 kg ha-1 yr-1 for the whole PRD. The distribution of N dry deposition was mainly controlled by the concentration of reactive N compounds and precipitation governed the wet deposition distribution. The modeling results also indicate that the PRD area is the source region in which the emissions exceed the deposition while the outside area of the PRD is the receptor region in which the deposition exceeds emissions. The impact of emission change and land use change due to urbanization was also investigated using the WRF-Chem model. The results showed that atmospheric N deposition exhibits a direct response to emission change while the land use change impacts the atmospheric N deposition indirectly mainly through the modification of precipitation. As a result of great challenges in reduction of the reactive N emission, a scenario of rising N deposition in the PRD cannot be discarded in the future.

Removal of Encephalitozoon intestinalis, calicivirus, and coliphages by conventional drinking water treatment.

PubMed

Gerba, Charles P; Riley, Kelley R; Nwachuku, Nena; Ryu, Hodon; Abbaszadegan, Morteza

2003-07-01

The removal of the Microsporidia, Encephalitozoon intestinalis, feline calicivirus and coliphages MS-2, PRD-1, and Fr were evaluated during conventional drinking water treatment in a pilot plant. The treatment consisted of coagulation, sedimentation, and mixed media filtration. Fr coliphage was removed the most (3.21 log), followed by feline calicivirus (3.05 log), E. coli (2.67 log), E. intestinalis (2.47 log), MS-2 (2.51 log). and PRD-1 (1.85 log). With the exception of PRD-1 the greatest removal of the viruses occurred during the flocculation step of the water treatment process.

High Pressure Hydrogen Pressure Relief Devices: Accelerated Life Testing and Application Best Practices

DOE Office of Scientific and Technical Information (OSTI.GOV)

Burgess, Robert M.; Post, Matthew B.; Buttner, William J.

Pressure relief devices (PRDs ) are used to protect high pressure systems from burst failure caused by overpressurization. Codes and standards require the use of PRDs for the safe design of many pressurized systems. These systems require high reliability due to the risks associated with a burst failure. Hydrogen service can increase the risk of PRD failure due to material property degradation caused by hydrogen attack. The National Renewable Energy Laboratory (NREL) has conducted an accelerated life test on a conventional spring loaded PRD. Based on previous failures in the field, the nozzles specific to these PRDs are of particularmore » interest. A nozzle in a PRD is a small part that directs the flow of fluid toward the sealing surface to maintain the open state of the valve once the spring force is overcome. The nozzle in this specific PRD is subjected to the full tensile force of the fluid pressure. These nozzles are made from 440C material, which is a type of hardened steel that is commonly chosen for high pressure applications because of its high strength properties. In a hydrogen environment, however, 440C is considered a worst case material since hydrogen attack results in a loss of almost all ductility and thus 440C is prone to fatigue and material failure. Accordingly, 440C is not recommended for hydrogen service. Conducting an accelerated life test on a PRD with 440C material provides information on necessary and sufficient conditions required to produce crack initiation and failure. The accelerated life test also provides information on other PRD failure modes that are somewhat statistically random in nature.« less

PRD3000: A novel Personnel Radiation Detector with Radiation Exposure Monitoring

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fallu-Labruyere, A.; Micou, C.; Schulcz, F.

PRD3000{sup TM} is a novel Personal Radiation Detector (PRD) with personnel radiation dose exposure monitoring. It is intended for First Responders, Law Enforcement, Customs Inspectors protecting critical infrastructures for detecting unexpected radioactive sources, who also need real time Hp(10) dose equivalent information. Traditional PRD devices use scintillator materials instrumented through either a photomultiplier tube or a photodiode photodetector. While the former is bulky and sensitive to magnetic fields, the latter has to compromise radiation sensitivity and energy threshold given its current noise per unit of photo-detection surface. Recently, solid state photodetectors (SiPM), based on arrays of Geiger operated diodes, havemore » emerged as a scalable digital photodetector for photon counting. Their strong breakdown voltage temperature dependence (on the order of tens of milli-volts per K) has however limited their use for portable instruments where strong temperature gradients can be experienced, and limited power is available to temperature stabilize. The PRD3000 is based on the industry standard DMC3000 active dosimeter that complies with IEC 61526 Ed. 3 and ANSI 42.20 for direct reading personal dose equivalent meters and active personnel radiation monitors. An extension module is based on a CsI(Tl) scintillator readout by a temperature compensated SiPM. Preliminary nuclear tests combined with a measured continuous operation in excess of 240 hours from a single AAA battery cell indicate that the PRD3000 complies with the IEC 62401 Ed.2 and ANSI 42.32 without sacrificing battery life time. We present a summary of the device test results, starting with performance stability over a temperature range of - 20 deg. C to 50 deg. C, false alarm rates and dynamic response time. (authors)« less

The possible protective effects of dipyridamole on ischemic reperfusion injury of priapism

PubMed Central

Karaguzel, Ersagun; Bayraktar, Cemil; Kutlu, Omer; Yulug, Esin; Mentese, Ahmet; Okatan, Ali Ertan; Colak, Fatih; Ozer, Serap; O.Kazaz, Ilke

2016-01-01

ABSTRACT Purpose To investigate the protective effects against ischemia reperfusion injury of dipyridamole in a model of induced priapism in rats. Materials and Methods Twenty-four male Sprague-Dawley rats were divided into four groups, control, P/R, P/R+DMSO and P/R+D. 3ml blood specimens were collected from vena cava inferior in order to determine serum MDA, IMA, TAS, TOS and OSI values, and penile tissue was taken for histopathological examination in control group. Priapism was induced in P/R group. After 1h, priapism was concluded and 30 min reperfusion was performed. In P/R+DMSO group 1ml/kg DMSO was administered intraperitoneally 30 min before reperfusion, while in P/R+D group 10mg/kg dipyridamole was administered intraperitoneally 30 min before reperfusion. Blood and penis specimens were collected after the end of 30 min reperfusion period. Sinusoidal area (µm2), tears in tunica albuginea and injury parameters in sinusoidal endothelium of penis were investigated. Results Histopathological examination revealed no significant changes in term of sinusoidal area. A decrease in tears was observed in P/R+D group compared to P/R group (p<0.05). Endothelial injury decreased in P/R+D group compared to P/R group (p>0.05). There were no significant differences in MDA and IMA values between groups. A significant increase in TOS and OSI values was observed in P/R+D group compared to P/R group. A significant decrease in TAS levels was observed in P/R+D group compared to the P/R group. Conclusions The administration of dipyridamole before reperfusion in ischemic priapism model has a potential protective effect against histopathological injury of the penis. PMID:27136481

Evaluating and Reporting Dysphagia in Trials of Chemoirradiation for Head-and-Neck Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gluck, Iris; Feng, Felix Y.; Lyden, Teresa

2010-07-01

Purpose: Reporting long-term toxicities in trials of chemoirradiation (CRT) of head-and-neck cancer (HNC) has mostly been limited to observer-rated maximal Grades {>=}3. We evaluated this reporting approach for dysphagia by assessing patient-reported dysphagia (PRD) and objective swallowing dysfunction through videofluoroscopy (VF) in patients with various grades of maximal observer-reported dysphagia (ORD). Methods and Materials: A total of 62 HNC patients completed quality-of-life questionnaires periodically through 12 months post-CRT. Five PRD items were selected: three dysphagia-specific questions, an Eating-Domain, and 'Overall Bother.' They underwent VF at 3 and 12 months, and ORD (Common Terminology Criteria for Adverse Events) scoring every 2more » months. We classified patients into four groups (0-3) according to maximal ORD scores documented 3-12 months post-CRT, and assessed PRD and VF summary scores in each group. Results: Differences in ORD scores among the groups were considerable throughout the observation period. In contrast, PRD scores were similar between Groups 2 and 3, and variable in Group 1. VF scores were worse in Group 3 compared with 2 at 3 months but similar at 12 months. In Group 1, PRD and VF scores from 3 through 12 months were close to Groups 2 and 3 if ORD score 1 persisted, but were similar to Group 0 in patients whose ORD scores improved by 12 months. Conclusions: Patients with lower maximal ORD grades, especially if persistent, had similar rates of PRD and objective dysphagia as patients with highest grades. Lower ORD grades should therefore be reported. These findings may have implications for reporting additional toxicities besides dysphagia.« less

Use of PRD1 bacteriophage in groundwater viral transport, inactivation, and attachment studies

USGS Publications Warehouse

Harvey, R.W.; Ryan, J.N.

2004-01-01

PRD1, an icosahedra-shaped, 62 nm (diameter), double-stranded DNA bacteriophage with an internal membrane, has emerged as an important model virus for studying the manner in which microorganisms are transported through a variety of groundwater environments. The popularity of this phage for use in transport studies involving geologic media is due, in part, to its relative stability over a range of temperatures and low degree of attachment in aquifer sediments. Laboratory and field investigations employing PRD1 are leading to a better understanding of viral attachment and transport behaviors in saturated geologic media and to improved methods for describing mathematically subsurface microbial transport at environmentally significant field scales. Radioisotopic labeling of PRD1 is facilitating additional information about the nature of viral interactions with solid surfaces in geologic media, the importance of iron oxide surfaces, and allowing differentiation between inactivation and attachment in field-scale tracer tests. ?? 2004 Published by Elsevier B.V. on behalf of the Federation of European Microbiological Societies.

Removal of adenovirus, calicivirus, and bacteriophages by conventional drinking water treatment.

PubMed

Abbaszadegan, Morteza; Monteiro, Patricia; Nwachuku, Nena; Alum, Absar; Ryu, Hodon

2008-02-01

This study was conducted to evaluate the removal of adenovirus, feline calicivirus (FCV), and bacteriophages MS-2, fr, PRD-1, and Phi X-174 during conventional drinking water treatment using ferric chloride as a coagulant. Adenovirus and FCV were removed to a greater extent than PRD-1 and Phi X-174, indicating that these bacteriophages may be appropriate surrogates for both adenovirus and FCV. Of the four bacteriophages studied in the pilot plant, MS-2 was removed to the greatest extent (5.1 log), followed by fr (4.9 log), PRD-1 (3.5 log), and Phi X-174 (1.3 log). The virus removal trend in the pilot-scale testing was similar to the bench-scale testing; however, the bench-scale testing seemed to provide a conservative estimate of the pilot plant performance. In the pilot-scale testing, MS-2 and fr were removed with the greatest efficiency during filtration, whereas PRD-1 and Phi X-174 showed the greatest removal during sedimentation.

[Anthropogenic ammonia emission inventory and characteristics in the Pearl River Delta Region].

PubMed

Yin, Sha-sha; Zheng, Jun-yu; Zhang, Li-jun; Zhong, Liu-ju

2010-05-01

Based on the collected activity data and emission factors of anthropogenic ammonia sources, a 2006-based anthropogenic ammonia emission inventory was developed for the Pearl River Delta (PRD) region by source categories and cities with the use of appropriate estimation methods. The results show: (1) the total NH3 emission from anthropogenic sources in the PRD region was 194. 8 kt; (2) the agriculture sources were major contributors of anthropogenic ammonia sources, in which livestock sources shared 62.1% of total NH3 emission and the contribution of application of nitrogen fertilizers was 21.7%; (3) the broiler was the largest contributor among the livestock sources, accounting for 43.4% of the livestock emissions, followed by the hog with a contribution of 32.1%; (4) Guangzhou was the largest ammonia emission city in the PRD region, and then Jiangmen, accounting for 23.4% and 19.1% of total NH3 emission in the PRD region respectively, with major sources as livestock sources and application of nitrogen fertilizers.

[Distribution of Regional Pollution and the Characteristics of Vertical Wind Field in the Pearl River Delta].

PubMed

Liu, Jian; Wu, Dui; Fan, Shao-jia

2015-11-01

Based on the data of hourly PM2.5 concentration of 56 environmental monitoring stations and 9 cities over the Pearl River Delta (PRD) region, the distributions of PM2.5 pollution in PRD region were analyzed by systematic cluster analysis and correlational analysis. It was found that the regional pollution could be divided into 3 types. The first type was the pollution occurred in Dongguan, Guangzhou, Foshan and Jiangmen (I type), and the second type was the pollution occurred in Zhongshan, Zhuhai, Shenzhen and Huizhou (II type), while the last type was the pollution only occurred in Zhaoqing (III type). During the study period, they occurred 47, 7 and 128 days, respectively. During events of pollution type I, except Zhuhai, Shenzhen and Huizhou, the PM2.5 concentrations of other cities were generally high, while the PM2.5 concentration in whole PRD region was over 50.0 μg x m(-3) during events of pollution type II. The regions with higher PM2.5 concentration was mainly concentrated in Zhaoqing, Guangzhou and Foshan during events of pollution type III. The wind data from 4 wind profile radars located in PRD region was used to study the characteristics of vertical wind field of these 3 pollution types. It was found that the wind profiles of type I and III were similar that low layer and high layer were controlled by the southeast wind and the southwest wind, respectively. For type II, the low layer and high layer were influenced by northerly wind and westerly wind, respectively. Compared with other types, the wind speed and ventilation index of type II. were much higher, and the variation of wind direction at lower-middle-layer was much smaller. When PRD region was influenced by northerly winds, the PM2.5 concentration in the entire PRD region was higher. When PRD region was controlled by southeast wind, the PM2.5 concentrations of I and II areas were relatively lower, while the pollution in III area was relatively heavier.

Partial Root-Zone Drying of Olive (Olea europaea var. 'Chetoui') Induces Reduced Yield under Field Conditions.

PubMed

Dbara, Soumaya; Haworth, Matthew; Emiliani, Giovani; Ben Mimoun, Mehdi; Gómez-Cadenas, Aurelio; Centritto, Mauro

2016-01-01

The productivity of olive trees in arid and semi-arid environments is closely linked to irrigation. It is necessary to improve the efficiency of irrigation techniques to optimise the amount of olive fruit produced in relation to the volume of water used. Partial root-zone drying (PRD) is a water saving irrigation technique that theoretically allows the production of a root-to-shoot signal that modifies the physiology of the above-ground parts of the plant; specifically reducing stomatal conductance (gs) and improving water use efficiency (WUE). Partial root-zone drying has been successfully applied under field conditions to woody and non-woody crops; yet the few previous trials with olive trees have produced contrasting results. Thirty year-old olive trees (Olea europaea 'var. Chetoui') in a Tunisian grove were exposed to four treatments from May to October for three-years: 'control' plants received 100% of the potential evapotranspirative demand (ETc) applied to the whole root-zone; 'PRD100' were supplied with an identical volume of water to the control plants alternated between halves of the root-zone every ten-days; 'PRD50' were given 50% of ETc to half of the root-system, and; 'rain-fed' plants received no supplementary irrigation. Allowing part of the root-zone to dry resulted in reduced vegetative growth and lower yield: PRD100 decreased yield by ~47% during productive years. During the less productive years of the alternate bearing cycle, irrigation had no effect on yield; this suggests that withholding of water during 'off-years' may enhance the effectiveness of irrigation over a two-year cycle. The amount and quality of oil within the olive fruit was unaffected by the irrigation treatment. Photosynthesis declined in the PRD50 and rain-fed trees due to greater diffusive limitations and reduced biochemical uptake of CO2. Stomatal conductance and the foliar concentration of abscisic acid (ABA) were not altered by PRD100 irrigation, which may indicate the absence of a hormonal root-to-shoot signal. Rain-fed and PRD50 treatments induced increased stem water potential and increased foliar concentrations of ABA, proline and soluble sugars. The stomata of the olive trees were relatively insensitive to super-ambient increases in [CO2] and higher [ABA]. These characteristics of 'hydro-passive' stomatal behaviour indicate that the 'Chetoui' variety of olive tree used in this study lacks the physiological responses required for the successful exploitation of PRD techniques to increase yield and water productivity. Alternative irrigation techniques such as partial deficit irrigation may be more suitable for 'Chetoui' olive production.

Non-structural proteins P17 and P33 are involved in the assembly of the internal membrane-containing virus PRD1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Karttunen, Jenni; Mäntynen, Sari; Ihalainen, Teemu O.

2015-08-15

Bacteriophage PRD1, which has been studied intensively at the structural and functional levels, still has some gene products with unknown functions and certain aspects of the PRD1 assembly process have remained unsolved. In this study, we demonstrate that the phage-encoded non-structural proteins P17 and P33, either individually or together, complement the defect in a temperature-sensitive GroES mutant of Escherichia coli for host growth and PRD1 propagation. Confocal microscopy of fluorescent fusion proteins revealed co-localisation between P33 and P17 as well as between P33 and the host chaperonin GroEL. A fluorescence recovery after photobleaching assay demonstrated that the diffusion of themore » P33 fluorescent fusion protein was substantially slower in E. coli than theoretically calculated, presumably resulting from intermolecular interactions. Our results indicate that P33 and P17 function in procapsid assembly, possibly in association with the host chaperonin complex GroEL/GroES. - Highlights: • Two non-structural proteins of PRD1 are involved in the virus assembly. • P17 and P33 complement the defect in GroES of Escherichia coli. • P33 co-localises with GroEL and P17 in the bacterium. • Slow motion of P33 in the bacterium suggests association with cellular components.« less

Field and laboratory investigations of inactivation of viruses (PRD1 and MS2) attached to iron oxide-coated quartz san

USGS Publications Warehouse

Ryan, Joseph N.; Harvey, Ronald W.; Metge, David W.; Elimelech, Menachem; Navigato, Theresa; Pieper, Ann P.

2002-01-01

Field and laboratory experiments were conducted to investigate inactivation of viruses attached to mineral surfaces. In a natural gradient transport field experiment, bacteriophage PRD1, radiolabeled with 32P, was injected into a ferric oxyhydroxide-coated sand aquifer with bromide and linear alkylbenzene sulfonates. In a zone of the aquifer contaminated by secondary sewage infiltration, small fractions of infective and 32P-labeled PRD1 broke through with the bromide tracer, followed by the slow release of 84% of the 32P activity and only 0.011% of the infective PRD1. In the laboratory experiments, the inactivation of PRD1, labeled with 35S (protein capsid), and MS2, dual radiolabeled with 35S (protein capsid) and 32P (nucleic acid), was monitored in the presence of groundwater and sediment from the contaminated zone of the field site. Release of infective viruses decreased at a much faster rate than release of the radiolabels, indicating that attached viruses were undergoing surface inactivation. Disparities between 32P and35S release suggest that the inactivated viruses were released in a disintegrated state. Comparison of estimated solution and surface inactivation rates indicates solution inactivation is ∼3 times as fast as surface inactivation. The actual rate of surface inactivation may be substantially underestimated owing to slow release of inactivated viruses.

Human-induced hydrologic and geomorphic changes in the crisscross river network of the Pearl River Delta, South China

NASA Astrophysics Data System (ADS)

Chen, Y. D.; Chen, X. H.

2003-04-01

The West River, the North River and the East River, collectively called the Pearl River, have a total drainage area of 453,690 km2 in southern and southwestern China and flow into the South China Sea. The three rivers join together and form the Pearl River Delta (PRD) with an area of 26,820 km2. The crisscross river network (density: 0.68-1.07 km/km2) in the PRD is one of the most complicated deltaic drainage systems in the world. As the region experiencing the most rapid economic growth in China over the past two decades, the PRD has witnessed massive changes in both the social and the natural environment, leading to an urgent need of studying regional environmental changes caused by intensive human activities. This paper aims to summarize and illustrate a variety of human-induced hydrologic and geomorphic changes in the PRD river network and to present an analysis of the causes and effects of these changes. Findings of this study will help decision-makers to formulate river management and mitigation strategies and policies in the region. The hydrologic characteristics of the PRD river network have been altered to varying degrees in the following three main aspects. First and most importantly, stage has become higher or lower over the past several decades in an uneven manner in different parts of the delta. From the early 1950s to the 1980s, scattered and small embankments were enlarged and combined to expand land mass and reduce flood hazards in the PRD. However, reduction of water surface area and concentration of flow into major channels generally caused stage to go up slightly. Since the early 1990s, stage in the upper part of the PRD has significantly dropped down while the opposite situation has become more and more common in the central PRD where enormous flood damages have occurred. Secondly, corresponding to the stage changes, the stage-discharge relationship has been substantially modified, as evidenced by over 2 m drop of stage for the same amount of discharge. Thirdly, the ratio of flow partition into two channels at several river bifurcation points has continuously changed over the past decade. This is an excellent indication of an increasingly larger portion of river flow discharging from the West River channels into the North River delta, which was found to be a major reason making the middle part of the PRD more and more vulnerable to flooding in recent years. Closely associated with the hydrologic changes are alterations of river channel and estuarine morphologies. Such geomorphic changes primarily include noticeable or even alarmingly severe modification of river channel bed, extension of river mouth and contraction of estuary in the study region. It was found that the hydrologic and geomorphic changes that have occurred within a relatively short period of time are mainly consequences of a wide variety of human activities, coupled with influences of natural events, including (a) channel dredging of sand for construction usage, (b) combination of embankments and construction of dams, (c) channel constriction and reduction or complete loss of floodplain, (d) sea level rise, and (e) channel bed erosion by record floods. Finally, an analysis is presented to examine the effects of these changes on various issues such as flood prevention and control, river channel management and navigation, low-flow regimes and water supply, water quality and aquatic ecosystem protection in the PRD region.

Importance of Cross-redistribution in Scattering Polarization of Spectral Lines: The Cases of {sup 3}P−{sup 3}S Triplets of Mg i and Ca i

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sampoorna, M.; Nagendra, K. N., E-mail: sampoorna@iiap.res.in, E-mail: knn@iiap.res.in

Scattering on a multi-level atomic system has dominant contributions from resonance and Raman scattering. While initial and final levels are the same for resonance scattering, they are different for Raman scattering. The frequency redistribution for resonance scattering is described by the usual partial frequency redistribution functions of Hummer, while that for Raman scattering is described by cross-redistribution (XRD) function. In the present paper, we investigate the importance of XRD on linear polarization profiles of {sup 3}P−{sup 3}S triplets of Mg i and Ca i formed in an isothermal one-dimensional atmosphere. We show that XRD produces significant effects on the linearmore » polarization profiles when the wavelength separations between the line components of the multiplet are small, like in the cases of Mg i b and Ca i triplets.« less

Coping with Racism: What Works and Doesn't Work for Black Women?

ERIC Educational Resources Information Center

West, Lindsey M.; Donovan, Roxanne A.; Roemer, Lizabeth

2010-01-01

Perceived racial discrimination (PRD) has deleterious effects on Black Americans. However, there is minimal empirical research on the influence of gender and coping on the relationship between PRD and mental health. This study posited that coping style (i.e., problem-focused coping and avoidant coping) would moderate the relationship between PRD…

Effect of ferric oxyhydroxide grain coatings on the transport of bacteriophage PRD1 and Cryptosporidium parvum oocysts in saturated porous media

USGS Publications Warehouse

Abudalo, R.A.; Bogatsu, Y.G.; Ryan, J.N.; Harvey, R.W.; Metge, D.W.; Elimelech, M.

2005-01-01

To test the effect of geochemical heterogeneity on microorganism transport in saturated porous media, we measured the removal of two microorganisms, the bacteriophage PRD1 and oocysts of the protozoan parasite Cryptosporidium parvum, in flow-through columns of quartz sand coated by different amounts of a ferric oxyhydroxide. The experiments were conducted over ranges of ferric oxyhydroxide coating fraction of ?? = 0-0.12 for PRD1 and from ?? = 0-0.32 for the oocysts at pH 5.6-5.8 and 10-4 M ionic strength. To determine the effect of pH on the transport of the oocysts, experiments were also conducted over a pH range of 5.7-10.0 at a coating fraction of ?? = 0.04. Collision (attachment) efficiencies increased as the fraction of ferric oxyhydroxide coated quartz sand increased, from ?? = 0.0071 to 0.13 over ?? = 0-0.12 for PRD1 and from ?? = 0.059 to 0.75 over ?? = 0-0.32 for the oocysts. Increasing the pH from 5.7 to 10.0 resulted in a decrease in the oocyst collision efficiency as the pH exceeded the expected point of zero charge of the ferric oxyhydroxide coatings. The collision efficiencies correlated very well with the fraction of quartz sand coated by the ferric oxyhydroxide for PRD1 but not as well for the oocysts. ?? 2005 American Chemical Society.

Isoelectric point is an inadequate descriptor of MS2, Phi X 174 and PRD1 phages adhesion on abiotic surfaces.

PubMed

Dika, Christelle; Duval, Jérôme F L; Francius, Gregory; Perrin, Aline; Gantzer, Christophe

2015-05-15

MS2, Phi X 174 and PRD1 bacteriophages are commonly used as surrogates to evaluate pathogenic virus behavior in natural aquatic media. The interfacial properties of these model soft bioparticles are herein discussed in connection with their propensities to adhere onto abiotic surfaces that differ in terms of surface charges and hydrophobicities. The phages considered in this work exhibit distinct multilayered surface structures and their electrostatic charges are evaluated from the dependence of their electrophoretic mobilities on electrolyte concentration at neutral pH on the basis of electrokinetic theory for soft (bio)particles. The charges of the viruses probed by electrokinetics vary according to the sequence Phi X 174⩽PRD1≪MS2, where '<' stands for 'less charged than'. The hydrophobic/hydrophilic balances of the phages are further derived from their adhesions onto model hydrophobic and hydrophilic self-assembled mono-layers. The corresponding results lead to the following hydrophobicity sequence Phi X 174≪MS2

Crystal structure of Bacillus anthracis virulence regulator AtxA and effects of phosphorylated histidines on multimerization and activity

PubMed Central

Hammerstrom, Troy G.; Horton, Lori B.; Swick, Michelle C.; Joachimiak, Andrzej; Osipiuk, Jerzy; Koehler, Theresa M.

2015-01-01

Summary The Bacillus anthracis virulence regulator AtxA controls transcription of the anthrax toxin genes and capsule biosynthesis operon. AtxA activity is elevated during growth in media containing glucose and CO2/bicarbonate, and there is a positive correlation between the CO2/bicarbonate signal, AtxA activity, and homomultimerization. AtxA activity is also affected by phosphorylation at specific histidines. We show that AtxA crystallizes as a dimer. Distinct folds associated with predicted DNA-binding domains (HTH1 and HTH2) and phosphoenolpyruvate: carbohydrate phosphotransferase system-regulated domains (PRD1 and PRD2) are apparent. We tested AtxA variants containing single and double phosphomimetic (His → Asp) and phosphoablative (His → Ala) amino acid changes for activity in B. anthracis cultures and for protein-protein interactions in cell lysates. Reduced activity of AtxA H199A, lack of multimerization and activity of AtxAH379D variants, and predicted structural changes associated with phosphorylation support a model for control of AtxA function. We propose that (1) in the AtxA dimer, phosphorylation of H199 in PRD1 affects HTH2 positioning, influencing DNA-binding; and (2) phosphorylation of H379 in PRD2 disrupts dimer formation. The AtxA structure is the first reported high-resolution full-length structure of a PRD-containing regulator and can serve as a model for proteins of this family, especially those that link virulence to bacterial metabolism. PMID:25402841

Crystal structure of Bacillus anthracis virulence regulator AtxA and effects of phosphorylated histidines on multimerization and activity.

PubMed

Hammerstrom, Troy G; Horton, Lori B; Swick, Michelle C; Joachimiak, Andrzej; Osipiuk, Jerzy; Koehler, Theresa M

2015-02-01

The Bacillus anthracis virulence regulator AtxA controls transcription of the anthrax toxin genes and capsule biosynthetic operon. AtxA activity is elevated during growth in media containing glucose and CO(2)/bicarbonate, and there is a positive correlation between the CO(2)/bicarbonate signal, AtxA activity and homomultimerization. AtxA activity is also affected by phosphorylation at specific histidines. We show that AtxA crystallizes as a dimer. Distinct folds associated with predicted DNA-binding domains (HTH1 and HTH2) and phosphoenolpyruvate: carbohydrate phosphotransferase system-regulated domains (PRD1 and PRD2) are apparent. We tested AtxA variants containing single and double phosphomimetic (His→Asp) and phosphoablative (His→Ala) amino acid changes for activity in B. anthracis cultures and for protein-protein interactions in cell lysates. Reduced activity of AtxA H199A, lack of multimerization and activity of AtxAH379D variants, and predicted structural changes associated with phosphorylation support a model for control of AtxA function. We propose that (i) in the AtxA dimer, phosphorylation of H199 in PRD1 affects HTH2 positioning, influencing DNA-binding; and (ii) phosphorylation of H379 in PRD2 disrupts dimer formation. The AtxA structure is the first reported high-resolution full-length structure of a PRD-containing regulator, and can serve as a model for proteins of this family, especially those that link virulence to bacterial metabolism. © 2014 John Wiley & Sons Ltd.

Computational analysis of aircraft pressure relief doors

NASA Astrophysics Data System (ADS)

Schott, Tyler

Modern trends in commercial aircraft design have sought to improve fuel efficiency while reducing emissions by operating at higher pressures and temperatures than ever before. Consequently, greater demands are placed on the auxiliary bleed air systems used for a multitude of aircraft operations. The increased role of bleed air systems poses significant challenges for the pressure relief system to ensure the safe and reliable operation of the aircraft. The core compartment pressure relief door (PRD) is an essential component of the pressure relief system which functions to relieve internal pressure in the core casing of a high-bypass turbofan engine during a burst duct over-pressurization event. The successful modeling and analysis of a burst duct event are imperative to the design and development of PRD's to ensure that they will meet the increased demands placed on the pressure relief system. Leveraging high-performance computing coupled with advances in computational analysis, this thesis focuses on a comprehensive computational fluid dynamics (CFD) study to characterize turbulent flow dynamics and quantify the performance of a core compartment PRD across a range of operating conditions and geometric configurations. The CFD analysis was based on a compressible, steady-state, three-dimensional, Reynolds-averaged Navier-Stokes approach. Simulations were analyzed, and results show that variations in freestream conditions, plenum environment, and geometric configurations have a non-linear impact on the discharge, moment, thrust, and surface temperature characteristics. The CFD study revealed that the underlying physics for this behavior is explained by the interaction of vortices, jets, and shockwaves. This thesis research is innovative and provides a comprehensive and detailed analysis of existing and novel PRD geometries over a range of realistic operating conditions representative of a burst duct over-pressurization event. Further, the study provides aircraft manufacturers with valuable insight into the impact that operating conditions and geometric configurations have on PRD performance and how the information can be used to assist future research and development of PRD design.

Partial Root-Zone Drying of Olive (Olea europaea var. 'Chetoui') Induces Reduced Yield under Field Conditions

PubMed Central

Dbara, Soumaya; Haworth, Matthew; Emiliani, Giovani; Ben Mimoun, Mehdi; Gómez-Cadenas, Aurelio; Centritto, Mauro

2016-01-01

The productivity of olive trees in arid and semi-arid environments is closely linked to irrigation. It is necessary to improve the efficiency of irrigation techniques to optimise the amount of olive fruit produced in relation to the volume of water used. Partial root-zone drying (PRD) is a water saving irrigation technique that theoretically allows the production of a root-to-shoot signal that modifies the physiology of the above-ground parts of the plant; specifically reducing stomatal conductance (gs) and improving water use efficiency (WUE). Partial root-zone drying has been successfully applied under field conditions to woody and non-woody crops; yet the few previous trials with olive trees have produced contrasting results. Thirty year-old olive trees (Olea europaea ‘var. Chetoui’) in a Tunisian grove were exposed to four treatments from May to October for three-years: ‘control’ plants received 100% of the potential evapotranspirative demand (ETc) applied to the whole root-zone; ‘PRD100’ were supplied with an identical volume of water to the control plants alternated between halves of the root-zone every ten-days; ‘PRD50’ were given 50% of ETc to half of the root-system, and; ‘rain-fed’ plants received no supplementary irrigation. Allowing part of the root-zone to dry resulted in reduced vegetative growth and lower yield: PRD100 decreased yield by ~47% during productive years. During the less productive years of the alternate bearing cycle, irrigation had no effect on yield; this suggests that withholding of water during ‘off-years’ may enhance the effectiveness of irrigation over a two-year cycle. The amount and quality of oil within the olive fruit was unaffected by the irrigation treatment. Photosynthesis declined in the PRD50 and rain-fed trees due to greater diffusive limitations and reduced biochemical uptake of CO2. Stomatal conductance and the foliar concentration of abscisic acid (ABA) were not altered by PRD100 irrigation, which may indicate the absence of a hormonal root-to-shoot signal. Rain-fed and PRD50 treatments induced increased stem water potential and increased foliar concentrations of ABA, proline and soluble sugars. The stomata of the olive trees were relatively insensitive to super-ambient increases in [CO2] and higher [ABA]. These characteristics of ‘hydro-passive’ stomatal behaviour indicate that the ‘Chetoui’ variety of olive tree used in this study lacks the physiological responses required for the successful exploitation of PRD techniques to increase yield and water productivity. Alternative irrigation techniques such as partial deficit irrigation may be more suitable for ‘Chetoui’ olive production. PMID:27315081

BACTERIOPHAGE PRD1 AND SILICA COLLOID TRANSPORT AND RECOVERY IN AN IRON OXIDE-COATED SAND AQUIFER. (R826179)

EPA Science Inventory

Bacteriophage PRD1 and silica colloids were co-injected into
sewage-contaminated and uncontaminated zones of an iron oxide-coated sand
aquifer on Cape Cod, MA, and their transport was monitored over distances up to
6 m in three arrays. After deposition, the attache...

78 FR 60850 - Endangered and Threatened Species; Notice of Intent To Prepare a Recovery Plan for Main Hawaiian...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-02

... information may be accessed at http://www.fpir.noaa.gov/PRD/prd_false_killer_whale.html . Authority: 16 U.S.C... False Killer Whale Distinct Population Segment AGENCY: National Marine Fisheries Service (NMFS... recovery plan; request for information. SUMMARY: The National Marine Fisheries Service (NMFS) is announcing...

Lessons from Preventing Reading Difficulties in Young Children for Adult Learning and Literacy

ERIC Educational Resources Information Center

Snow, Catherine E.; Strucker, John

1999-01-01

In the spring of 1998 the National Research Council released a report, Preventing Reading Difficulties in Young Children for Adult Learning and Literacy (PRD). PRD was written with the goal of contributing to the prevention of reading difficulties by documenting the contributions of research to an understanding of reading development and the…

Crystal structure of Bacillus anthracis virulence regulator AtxA and effects of phosphorylated histidines on multimerization and activity

DOE PAGES

Hammerstrom, Troy G.; Horton, Lori B.; Swick, Michelle C.; ...

2014-12-30

The Bacillus anthracis virulence regulator AtxA controls transcription of the anthrax toxin genes and capsule biosynthesis operon. AtxA activity is elevated during growth in media containing glucose and CO 2/bicarbonate, and there is a positive correlation between the CO 2/bicarbonate signal, AtxA activity, and homomultimerization. AtxA activity is also affected by phosphorylation at specific histidines. We show that AtxA crystallizes as a dimer. Distinct folds associated with predicted DNA-binding domains (HTH1 and HTH2) and phosphoenolpyruvate: carbohydrate phosphotransferase system-regulated domains (PRD1 and PRD2) are apparent. We tested AtxA variants containing single and double phosphomimetic (His → Asp) and phosphoablative (His →more » Ala) amino acid changes for activity in B. anthracis cultures and for protein-protein interactions in cell lysates. Reduced activity of AtxA H199A, lack of multimerization and activity of AtxAH379D variants, and predicted structural changes associated with phosphorylation support a model for control of AtxA function. We propose that (1) in the AtxA dimer, phosphorylation of H199 in PRD1 affects HTH2 positioning, influencing DNA-binding; and (2) phosphorylation of H379 in PRD2 disrupts dimer formation. In conclusion, the AtxA structure is the first reported high-resolution full-length structure of a PRD-containing regulator and can serve as a model for proteins of this family, especially those that link virulence to bacterial metabolism.« less

Crystal structure of Bacillus anthracis virulence regulator AtxA and effects of phosphorylated histidines on multimerization and activity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hammerstrom, Troy G.; Horton, Lori B.; Swick, Michelle C.

The Bacillus anthracis virulence regulator AtxA controls transcription of the anthrax toxin genes and capsule biosynthesis operon. AtxA activity is elevated during growth in media containing glucose and CO 2/bicarbonate, and there is a positive correlation between the CO 2/bicarbonate signal, AtxA activity, and homomultimerization. AtxA activity is also affected by phosphorylation at specific histidines. We show that AtxA crystallizes as a dimer. Distinct folds associated with predicted DNA-binding domains (HTH1 and HTH2) and phosphoenolpyruvate: carbohydrate phosphotransferase system-regulated domains (PRD1 and PRD2) are apparent. We tested AtxA variants containing single and double phosphomimetic (His → Asp) and phosphoablative (His →more » Ala) amino acid changes for activity in B. anthracis cultures and for protein-protein interactions in cell lysates. Reduced activity of AtxA H199A, lack of multimerization and activity of AtxAH379D variants, and predicted structural changes associated with phosphorylation support a model for control of AtxA function. We propose that (1) in the AtxA dimer, phosphorylation of H199 in PRD1 affects HTH2 positioning, influencing DNA-binding; and (2) phosphorylation of H379 in PRD2 disrupts dimer formation. In conclusion, the AtxA structure is the first reported high-resolution full-length structure of a PRD-containing regulator and can serve as a model for proteins of this family, especially those that link virulence to bacterial metabolism.« less

Effect of pH on bacteriophage transport through sandy soils

USGS Publications Warehouse

Kinoshita, Takashi; Bales, Roger C.; Maguire, Kimberley M.; Gerba, Charles P.

1993-01-01

Effects of pH and hydrophobicity on attachment and detachment of PRD-1 and MS-2 in three different sandy soils were investigated in a series of laboratory-column experiments. Concentrations of the lipid-containing phage PRD-1 decreased 3–4 orders of magnitude during passage through the 10–15-cm-long columns. Attachment of the lipid-containing phage PRD-1 was insensitive to pH and was apparently controlled by hydrophobic interactions in soil media. The less-hydrophobic phage MS-2 acted conservatively; it was not removed in the columns at pH's 5.7–8.0. The sticking efficiency (α) in a colloid-filtration model was between 0.1 and 1 for PRD-1, indicating a relatively high removal efficiency. Phage attachment was reversible, but detachment under steady-state conditions was slow. An increase in pH had a moderate effect on enhancing detachment. Still, these soils should continue to release phage to virus-free water for days to weeks following exposure to virus-containing water. In sandy soils with a mass-fraction organic carbon as low as a few hundredths of a percent, pH changes in the range 5.7–8.0 should have little effect on retention of more-hydrophobic virus (e.g., PRD-1), in that retardation will be dominated by hydrophobic effects. Sharp increases in pH should enhance detachment and transport of virus previously deposited on soil grains. A more hydrophilic virus (e.g., MS-2) will transport as a conservative tracer in low-carbon sandy soil.

Structure of the Intermediate Filament-Binding Region of Desmoplakin

DOE PAGES

Kang, Hyunook; Weiss, Thomas M.; Bang, Injin; ...

2016-01-25

Here, desmoplakin (DP) is a cytoskeletal linker protein that connects the desmosomal cadherin/plakoglobin/plakophilin complex to intermediate filaments (IFs). The C-terminal region of DP (DPCT) mediates IF binding, and contains three plakin repeat domains (PRDs), termed PRD-A, PRD-B and PRD-C. Previous crystal structures of PRDs B and C revealed that each is formed by 4.5 copies of a plakin repeat (PR) and has a conserved positively charged groove on its surface. Although PRDs A and B are linked by just four amino acids, B and C are separated by a 154 residue flexible linker, which has hindered crystallographic analysis of themore » full DPCT. Here we present the crystal structure of a DPCT fragment spanning PRDs A and B, and elucidate the overall architecture of DPCT by small angle X-ray scattering (SAXS) analysis. The structure of PRD-A is similar to that of PRD-B, and the two domains are arranged in a quasi-linear arrangement, and separated by a 4 amino acid linker. Analysis of the B-C linker region using secondary structure prediction and the crystal structure of a homologous linker from the cytolinker periplakin suggests that the N-terminal ~100 amino acids of the linker form two PR-like motifs. SAXS analysis of DPCT indicates an elongated but non-linear shape with R g = 51.5 Å and D max = 178 Å. These data provide the first structural insights into an IF binding protein containing multiple PRDs and provide a foundation for studying the molecular basis of DP-IF interactions.« less

Crystal structure of B acillus anthracis virulence regulator AtxA and effects of phosphorylated histidines on multimerization and activity: AtxA multimerization, phosphorylation and activity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hammerstrom, Troy G.; Horton, Lori B.; Swick, Michelle C.

2014-12-30

The Bacillus anthracis virulence regulator AtxA controls transcription of the anthrax toxin genes and capsule biosynthetic operon. AtxA activity is elevated during growth in media containing glucose and CO2/bicarbonate, and there is a positive correlation between the CO2/bicarbonate signal, AtxA activity and homomultimerization. AtxA activity is also affected by phosphorylation at specific histidines. We show that AtxA crystallizes as a dimer. Distinct folds associated with predicted DNA-binding domains (HTH1 and HTH2) and phosphoenolpyruvate: carbohydrate phosphotransferase system-regulated domains (PRD1 and PRD2) are apparent. We tested AtxA variants containing single and double phosphomimetic (HisAsp) and phosphoablative (HisAla) amino acid changes for activitymore » in B.anthracis cultures and for protein-protein interactions in cell lysates. Reduced activity of AtxA H199A, lack of multimerization and activity of AtxAH379D variants, and predicted structural changes associated with phosphorylation support a model for control of AtxA function. We propose that (i) in the AtxA dimer, phosphorylation of H199 in PRD1 affects HTH2 positioning, influencing DNA-binding; and (ii) phosphorylation of H379 in PRD2 disrupts dimer formation. The AtxA structure is the first reported high-resolution full-length structure of a PRD-containing regulator, and can serve as a model for proteins of this family, especially those that link virulence to bacterial metabolism.« less

Aging results for PRD 49 III/epoxy and Kevlar 49/epoxy composite pressure vessels

NASA Technical Reports Server (NTRS)

Hamstad, M. A.

1983-01-01

Kevlar 49/epoxy composite is growing in use as a structural material because of its high strength-to-weight ratio. Currently, it is used for the Trident rocket motor case and for various pressure vessels on the Space Shuttle. In 1979, the initial results for aging of filament-wound cylindrical pressure vessels which were manufactured with preproduction Kevlar 49 (Hamstad, 1979) were published. This preproduction fiber was called PRD 49 III. This report updates the continuing study to 10-year data and also presents 7.5-year data for spherical pressure vessels wound with production Kevlar 49. For completeness, this report will again describe the specimens of the original study with PRD 49 as well as specimens for the new study with Kevlar 49.

An Overview of the 3C-STAR project

NASA Astrophysics Data System (ADS)

Zhang, Y.

2009-04-01

Over the past three decades, city clusters have played a leading role in the economic growth of China, owing to their collective economic capacity and interdependency. However, pollution prevention lags behind the economic boom, led to a general decline in air quality in city clusters. As a result, industrial emissions and traffic exhausts together contribute to high levels of ozone (O3) and fine particulate matter (PM2.5) pollution problems ranging from urban to regional scale. Such high levels of both primary and secondary airborne pollutants lead to the development of a (perhaps typically Chinese) "air pollution complex" concept. Air pollution complex is particularly true and significant in Beijing-Tianjin area, Pearl River Delta (PRD) and Yangtze River Delta. The concurrent high concentrations of O3 and PM2.5 in PRD as well as in other China city clusters have led to rather unique pollution characteristics due to interactions between primary emissions and photochemical processes, between gaseous compounds and aerosol phase species, and between local and regional scale processes. The knowledge and experience needed to find solutions to the unique pollution complex in China are still lacking. Starting from 2007, we launch a major project "Synthesized Prevention Techniques for Air Pollution Complex and Integrated Demonstration in Key City-Cluster Region" (3C-STAR) to address those problems scientifically and technically. The purpose of the project is to build up the capacity of regional air pollution control and to establish regional coordination mechanism for joint implementation of pollution control. The project includes a number of key components technically: regional air quality monitoring network and super-sites, regional dynamic emission inventory of multi-pollutants, regional ensemble air quality forecasting model system, and regional management system supported by decision making platform. The 3C-STAR project selected PRD as a core area to have technical demonstration, and thus provide opportunities as well as challenges for PRD to improve its regional air quality. An integrated field measurement campaign 3C-STAR2008 was organized during October 15-November 19, 2008, including 3-D regional air quality monitoring network, two super-sites, and in-site meteorological and air quality forecasting. With the efforts of more than 100 scientists and students from 12 research institutes, the 3C-STAR2008 was conducted with great success. A great amount of data with rigorous QA/QC procedures has been obtained and data analysis is underway. In this talk, an overview of the 3C-STAR project will be presented, together with major findings from previous PRD campaigns (PRD2004 and PRD2006).

Bacillus subtilis mutant LicT antiterminators exhibiting enzyme I- and HPr-independent antitermination affect catabolite repression of the bglPH operon.

PubMed

Lindner, Cordula; Hecker, Michael; Le Coq, Dominique; Deutscher, Josef

2002-09-01

The Bacillus subtilis antiterminator LicT regulates the expression of bglPH and bglS, which encode the enzymes for the metabolism of aryl-beta-glucosides and the beta-glucanase BglS. The N-terminal domain of LicT (first 55 amino acids) prevents the formation of rho-independent terminators on the respective transcripts by binding to target sites overlapping these terminators. Proteins of the phosphoenolpyruvate:carbohydrate phosphotransferase system (PTS) regulate the antitermination activity of LicT by phosphorylating histidines in its two PTS regulation domains (PRDs). Phosphorylation at His-100 in PRD-1 requires the PTS proteins enzyme I and HPr and the phosphorylated permease BglP and inactivates LicT. During transport and phosphorylation of aryl-beta-glucosides, BglP is dephosphorylated, which renders LicT active and thus leads to bglPH and bglS induction. In contrast, phosphorylation at His-207 and/or His-269 in PRD-2, which requires only enzyme I and HPr, is absolutely necessary for LicT activity and bglPH and bglS expression. We isolated spontaneous licT mutants expressing bglPH even when enzyme I and HPr were absent (as indicated by the designation "Pia" [PTS-independent antitermination]). Introduced in a ptsHI(+) strain, two classes of licT(Pia) mutations could be distinguished. Mutants synthesizing LicT(Pia) antiterminators altered in PRD-2 still required induction by aryl-beta-glucosides, whereas mutations affecting PRD-1 caused constitutive bglPH expression. One of the two carbon catabolite repression (CCR) mechanisms operative for bglPH requires the rho-independent terminator and is probably prevented when LicT is activated by P approximately His-HPr-dependent phosphorylation in PRD-2 (where the prefix "P approximately " stands for "phospho"). During CCR, the small amount of P approximately His-HPr present in cells growing on repressing PTS sugars probably leads to insufficient phosphorylation at PRD-2 of LicT and therefore to reduced bglPH expression. In agreement with this concept, mutants synthesizing a P approximately His-HPr-independent LicT(Pia) had lost LicT-modulated CCR.

Bacillus subtilis Mutant LicT Antiterminators Exhibiting Enzyme I- and HPr-Independent Antitermination Affect Catabolite Repression of the bglPH Operon

PubMed Central

Lindner, Cordula; Hecker, Michael; Le Coq, Dominique; Deutscher, Josef

2002-01-01

The Bacillus subtilis antiterminator LicT regulates the expression of bglPH and bglS, which encode the enzymes for the metabolism of aryl-β-glucosides and the β-glucanase BglS. The N-terminal domain of LicT (first 55 amino acids) prevents the formation of ρ-independent terminators on the respective transcripts by binding to target sites overlapping these terminators. Proteins of the phosphoenolpyruvate:carbohydrate phosphotransferase system (PTS) regulate the antitermination activity of LicT by phosphorylating histidines in its two PTS regulation domains (PRDs). Phosphorylation at His-100 in PRD-1 requires the PTS proteins enzyme I and HPr and the phosphorylated permease BglP and inactivates LicT. During transport and phosphorylation of aryl-β-glucosides, BglP is dephosphorylated, which renders LicT active and thus leads to bglPH and bglS induction. In contrast, phosphorylation at His-207 and/or His-269 in PRD-2, which requires only enzyme I and HPr, is absolutely necessary for LicT activity and bglPH and bglS expression. We isolated spontaneous licT mutants expressing bglPH even when enzyme I and HPr were absent (as indicated by the designation “Pia” [PTS-independent antitermination]). Introduced in a ptsHI+ strain, two classes of licT(Pia) mutations could be distinguished. Mutants synthesizing LicT(Pia) antiterminators altered in PRD-2 still required induction by aryl-β-glucosides, whereas mutations affecting PRD-1 caused constitutive bglPH expression. One of the two carbon catabolite repression (CCR) mechanisms operative for bglPH requires the ρ-independent terminator and is probably prevented when LicT is activated by P∼His-HPr-dependent phosphorylation in PRD-2 (where the prefix “P∼” stands for “phospho”). During CCR, the small amount of P∼His-HPr present in cells growing on repressing PTS sugars probably leads to insufficient phosphorylation at PRD-2 of LicT and therefore to reduced bglPH expression. In agreement with this concept, mutants synthesizing a P∼His-HPr-independent LicT(Pia) had lost LicT-modulated CCR. PMID:12169607

Plasticity in stomatal size and density of potato leaves under different irrigation and phosphorus regimes.

PubMed

Sun, Yanqi; Yan, Fei; Cui, Xiaoyong; Liu, Fulai

2014-09-01

The morphological features of stomata including their size and density could be modulated by environmental cues; however, the underlying mechanisms remain largely elusive. Here, the effect of different irrigation and phosphorus (P) regimes on stomatal size (SS) and stomatal density (SD) of potato leaves was investigated. The plants were grown in split-root pots under two P fertilization rates (viz., 0 and 100mgkg(-1) soil, denoted as P0 and P1, respectively) and subjected to full (FI), deficit (DI), and partial root-zone drying (PRD) irrigation regimes. Results showed that SS and SD were unresponsive to P but significantly affected by the irrigation treatment. FI plants had the largest SS, followed by DI, and PRD the smallest; and the reverse was the case for SD. Compared to FI and DI, PRD plants had significantly lower values of specific leaf area (SLA) and leaf carbon isotope discrimination (Δ(13)C) under P0. Midday leaf water potential (Ψleaf) and stomatal conductance (gs) was similar for DI and PRD, which was significantly lower than that of FI. Leaf contents of C, N, K, Ca and Mg were higher in PRD than in DI plants, particularly under P0. When analyzed across the three irrigation regimes, it was found that the P1 plants had significantly higher leaf contents of P and Mg, but significantly lower leaf K content compared to the P0 plants. Linear correlation analyses revealed that SS was positively correlated with Ψleaf and Δ(13)C; whereas SD was negatively correlated with Ψleaf, Δ(13)C and SLA, and positively correlated with leaf C, N and Ca contents. And gs was positively correlated with SS but negatively correlated with SD. Collectively, under low P level, the smaller and denser stomata in PRD plants may bring about a more efficient stomatal control over gas exchange, hereby potentially enhance water-use efficiency as exemplified by the lowered leaf Δ(13)C under fluctuating soil moisture conditions. Copyright © 2014 Elsevier GmbH. All rights reserved.

Host Status of Different Potato (Solanum tuberosum) Varieties and Hatching in Root Diffusates of Globodera ellingtonae

PubMed Central

Zasada, Inga A.; Peetz, Amy; Wade, Nadine; Navarre, Roy A.; Ingham, Russ E.

2013-01-01

Globodera ellingtonae was detected in Oregon in 2008. In order to make decisions regarding the regulation of this nematode, knowledge of its biology is required. We determined the host status of a diversity of potato (Solanum tuberosum) varieties in soil-based experiments and identified hatching stimulants in in vitro hatching assays. ‘Russet Burbank,’ ‘Desiree,’ ‘Modac,’ ‘Norland,’ ‘Umatilla,’ and ‘Yukon Gold’ were good hosts (RF > 14) for G. ellingtonae. Potato varieties ‘Maris Piper,’ ‘Atlantic,’ and ‘Satina,’ all which contain the Ro1 gene that confers resistance to G. rostochiensis, were not hosts for G. ellingtonae. In in vitro hatching assays, G. ellingtonae hatched readily in the presence of diffusates from potato (PRD) and tomato (Solanum lycopersicum; TRD). Egg hatch occurred in an average of between 87% and 90% of exposed cysts, with an average of between 144 and 164 juveniles emerging per cyst, from PRD- and TRD-treated cysts, respectively. This nematode hatched rapidly in the presence of PRD and TRD, with at least 66% of total hatch occurring by day 3 of exposure. There was no dose-response of egg hatch to concentrations of PRD or TRD ranging from 1:5 to 1:100 diffusate to water. When G. ellingtonae was exposed to root diffusates from 21 different plants, hatch occurred in 0% to 70% of exposed cysts, with an average of between 0 to 27 juveniles emerging per cyst. When root diffusate-exposed cysts were subsequently transferred to PRD to test viability, root diffusates from arugula (Eruca sativa), sudangrass (Sorghum bicolor subsp. drummondii), and common vetch (Vicia sativa) continued to inhibit egg hatch compared with the other root diffusates or water in which hatch occurred readily (60 to 182 juveniles emerging per cyst). Previously known hatching stimulants of G. rostochiensis and G. pallida, sodium metavanadate, sodium orthovanadate, and sodium thiocyanate, stimulated some egg hatch. Although, Globodera ellingtonae hatched readily in PRD and TRD and reproduced on potato, the pathogenicity of this nematode on potato remains to be determined. PMID:24115784

Host Status of Different Potato (Solanum tuberosum) Varieties and Hatching in Root Diffusates of Globodera ellingtonae.

PubMed

Zasada, Inga A; Peetz, Amy; Wade, Nadine; Navarre, Roy A; Ingham, Russ E

2013-09-01

Globodera ellingtonae was detected in Oregon in 2008. In order to make decisions regarding the regulation of this nematode, knowledge of its biology is required. We determined the host status of a diversity of potato (Solanum tuberosum) varieties in soil-based experiments and identified hatching stimulants in in vitro hatching assays. 'Russet Burbank,' 'Desiree,' 'Modac,' 'Norland,' 'Umatilla,' and 'Yukon Gold' were good hosts (RF > 14) for G. ellingtonae. Potato varieties 'Maris Piper,' 'Atlantic,' and 'Satina,' all which contain the Ro1 gene that confers resistance to G. rostochiensis, were not hosts for G. ellingtonae. In in vitro hatching assays, G. ellingtonae hatched readily in the presence of diffusates from potato (PRD) and tomato (Solanum lycopersicum; TRD). Egg hatch occurred in an average of between 87% and 90% of exposed cysts, with an average of between 144 and 164 juveniles emerging per cyst, from PRD- and TRD-treated cysts, respectively. This nematode hatched rapidly in the presence of PRD and TRD, with at least 66% of total hatch occurring by day 3 of exposure. There was no dose-response of egg hatch to concentrations of PRD or TRD ranging from 1:5 to 1:100 diffusate to water. When G. ellingtonae was exposed to root diffusates from 21 different plants, hatch occurred in 0% to 70% of exposed cysts, with an average of between 0 to 27 juveniles emerging per cyst. When root diffusate-exposed cysts were subsequently transferred to PRD to test viability, root diffusates from arugula (Eruca sativa), sudangrass (Sorghum bicolor subsp. drummondii), and common vetch (Vicia sativa) continued to inhibit egg hatch compared with the other root diffusates or water in which hatch occurred readily (60 to 182 juveniles emerging per cyst). Previously known hatching stimulants of G. rostochiensis and G. pallida, sodium metavanadate, sodium orthovanadate, and sodium thiocyanate, stimulated some egg hatch. Although, Globodera ellingtonae hatched readily in PRD and TRD and reproduced on potato, the pathogenicity of this nematode on potato remains to be determined.

Design Tools to Assess Hydro-Turbine Biological Performance: Priest Rapids Dam Turbine Replacement Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Richmond, Marshall C.; Rakowski, Cynthia L.; Serkowski, John A.

2013-06-25

Over the past two decades, there have been many studies describing injury mechanisms associated with turbine passage, the response of various fish species to these mechanisms, and the probability of survival through dams. Although developing tools to design turbines that improve passage survival has been difficult and slow, a more robust quantification of the turbine environment has emerged through integrating physical model data, fish survival data, and computational fluid dynamics (CFD) studies. Grant County Public Utility District (GCPUD) operates the Priest Rapids Dam (PRD), a hydroelectric facility on the Columbia River in Washington State. The dam contains 10 Kaplan-type turbinemore » units that are now almost 50 years old. The Utility District plans to refit all of these aging turbines with new turbines. The Columbia River at PRD is a migratory pathway for several species of juvenile and adult salmonids, so passage of fish through the dam is a major consideration when replacing the turbines. In this presentation, a method for turbine biological performance assessment (BioPA) is introduced. Using this method, a suite of biological performance indicators is computed based on simulated data from a CFD model of a proposed turbine design. Each performance indicator is a measure of the probability of exposure to a certain dose of an injury mechanism. Using known relationships between the dose of an injury mechanism and frequency of injury (dose–response) from laboratory or field studies, the likelihood of fish injury for a turbine design can be computed from the performance indicator. By comparing the values of the indicators from proposed designs, the engineer can identify the more-promising alternatives. We will present application of the BioPA method for baseline risk assessment calculations for the existing Kaplan turbines at PRD that will be used as the minimum biological performance that a proposed new design must achieve.« less

Impacts of seasonal and regional variability in biogenic VOC emissions on surface ozone in the Pearl River Delta region, China

DOE Office of Scientific and Technical Information (OSTI.GOV)

Situ, S.; Guenther, Alex B.; Wang, X. J.

In this study, the BVOC emissions in November 2010 over the Pearl River Delta (PRD) region in southern China have been estimated by the latest version of a Biogenic Volatile Organic Compound (BVOC) emission model (MEGAN v2.1). The evaluation of MEGAN performance at a representative forest site within this region indicates MEGAN can estimate BVOC emissions reasonably well in this region except overestimating isoprene emission in autumn for reasons that are discussed in this manuscript. Along with the output from MEGAN, the Weather Research and Forecasting model with chemistry (WRF-Chem) is used to estimate the impacts of BVOC emissions onmore » surface ozone in the PRD region. The results show BVOC emissions increase the daytime ozone peak by *3 ppb on average, and the max hourly impacts of BVOC emissions on the daytime ozone peak is 24.8 ppb. Surface ozone mixing ratios in the central area of Guangzhou- Foshan and the western Jiangmen are most sensitive to BVOC emissions BVOCs from outside and central PRD influence the central area of Guangzhou-Foshan and the western Jiangmen significantly while BVOCs from rural PRD mainly influence the western Jiangmen. The impacts of BVOC emissions on surface ozone differ in different PRD cities, and the impact varies in different seasons. Foshan and Jiangmen being most affected in autumn, result in 6.0 ppb and 5.5 ppb increases in surface ozone concentrations, while Guangzhou and Huizhou become more affected in summer. Three additional experiments concerning the sensitivity of surface ozone to MEGAN input variables show that surface ozone is more sensitive to landcover change, followed by emission factors and meteorology.« less

Sap fluxes from different parts of the rootzone modulate xylem ABA concentration during partial rootzone drying and re-wetting

PubMed Central

Pérez-Pérez, J. G.; Dodd, I. C.

2015-01-01

Previous studies with partial rootzone drying (PRD) irrigation demonstrated that alternating the wet and dry parts of the rootzone (PRD-Alternated) increased leaf xylem ABA concentration ([X-ABA]leaf) compared with maintaining the same wet and dry parts of the rootzone (PRD-Fixed). To determine the relative contributions of different parts of the rootzone to this ABA signal, [X-ABA]leaf of potted, split-root tomato (Solanum lycopersicum) plants was modelled by quantifying the proportional water uptake from different soil compartments, and [X-ABA]leaf responses to the entire pot soil-water content (θpot). Continuously measuring soil-moisture depletion by, or sap fluxes from, different parts of the root system revealed that water uptake rapidly declined (within hours) after withholding water from part of the rootzone, but was rapidly restored (within minutes) upon re-watering. Two hours after re-watering part of the rootzone, [X-ABA]leaf was equally well predicted according to θpot alone and by accounting for the proportional water uptake from different parts of the rootzone. Six hours after re-watering part of the rootzone, water uptake by roots in drying soil was minimal and, instead, occurred mainly from the newly irrigated part of the rootzone, thus [X-ABA]leaf was best predicted by accounting for the proportional water uptake from different parts of the rootzone. Contrary to previous results, alternating the wet and dry parts of the rootzone did not enhance [X-ABA]leaf compared with PRD-Fixed irrigation. Further work is required to establish whether altered root-to-shoot ABA signalling contributes to the improved yields of crops grown with alternate, rather than fixed, PRD. PMID:25740924

Sap fluxes from different parts of the rootzone modulate xylem ABA concentration during partial rootzone drying and re-wetting.

PubMed

Pérez-Pérez, J G; Dodd, I C

2015-04-01

Previous studies with partial rootzone drying (PRD) irrigation demonstrated that alternating the wet and dry parts of the rootzone (PRD-Alternated) increased leaf xylem ABA concentration ([X-ABA]leaf) compared with maintaining the same wet and dry parts of the rootzone (PRD-Fixed). To determine the relative contributions of different parts of the rootzone to this ABA signal, [X-ABA]leaf of potted, split-root tomato (Solanum lycopersicum) plants was modelled by quantifying the proportional water uptake from different soil compartments, and [X-ABA]leaf responses to the entire pot soil-water content (θpot). Continuously measuring soil-moisture depletion by, or sap fluxes from, different parts of the root system revealed that water uptake rapidly declined (within hours) after withholding water from part of the rootzone, but was rapidly restored (within minutes) upon re-watering. Two hours after re-watering part of the rootzone, [X-ABA]leaf was equally well predicted according to θpot alone and by accounting for the proportional water uptake from different parts of the rootzone. Six hours after re-watering part of the rootzone, water uptake by roots in drying soil was minimal and, instead, occurred mainly from the newly irrigated part of the rootzone, thus [X-ABA]leaf was best predicted by accounting for the proportional water uptake from different parts of the rootzone. Contrary to previous results, alternating the wet and dry parts of the rootzone did not enhance [X-ABA]leaf compared with PRD-Fixed irrigation. Further work is required to establish whether altered root-to-shoot ABA signalling contributes to the improved yields of crops grown with alternate, rather than fixed, PRD. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

POLARIZED LINE FORMATION IN NON-MONOTONIC VELOCITY FIELDS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sampoorna, M.; Nagendra, K. N., E-mail: sampoorna@iiap.res.in, E-mail: knn@iiap.res.in

2016-12-10

For a correct interpretation of the observed spectro-polarimetric data from astrophysical objects such as the Sun, it is necessary to solve the polarized line transfer problems taking into account a realistic temperature structure, the dynamical state of the atmosphere, a realistic scattering mechanism (namely, the partial frequency redistribution—PRD), and the magnetic fields. In a recent paper, we studied the effects of monotonic vertical velocity fields on linearly polarized line profiles formed in isothermal atmospheres with and without magnetic fields. However, in general the velocity fields that prevail in dynamical atmospheres of astrophysical objects are non-monotonic. Stellar atmospheres with shocks, multi-componentmore » supernova atmospheres, and various kinds of wave motions in solar and stellar atmospheres are examples of non-monotonic velocity fields. Here we present studies on the effect of non-relativistic non-monotonic vertical velocity fields on the linearly polarized line profiles formed in semi-empirical atmospheres. We consider a two-level atom model and PRD scattering mechanism. We solve the polarized transfer equation in the comoving frame (CMF) of the fluid using a polarized accelerated lambda iteration method that has been appropriately modified for the problem at hand. We present numerical tests to validate the CMF method and also discuss the accuracy and numerical instabilities associated with it.« less

Frequency redistribution function for the polarized two-term atom

DOE Office of Scientific and Technical Information (OSTI.GOV)

Casini, R.; Landi Degl'Innocenti, M.; Manso Sainz, R.

2014-08-20

We present a generalized frequency redistribution function for the polarized two-term atom in an arbitrary magnetic field. This result is derived within a new formulation of the quantum problem of coherent scattering of polarized radiation by atoms in the collisionless regime. The general theory, which is based on a diagrammatic treatment of the atom-photon interaction, is still a work in progress. However, the results anticipated here are relevant enough for the study of the magnetism of the solar chromosphere and of interest for astrophysics in general.

Dye to use with virus challenge for testing barrier materials.

PubMed Central

Lytle, C D; Felten, R P; Truscott, W

1991-01-01

Can FD&C Blue no. 1 dye photoinactivate bacteriophages phi X174, T7, PRD1, and phi 6 under laboratory lighting conditions? At high levels of light, the dye (500 microM) photoinactivated only phi 6. Thus, this dye can be used at concentrations up to 500 microM with bacteriophages phi X174, T7, and PRD1 to test barrier material integrity. PMID:1872612

Bibliography of Soviet Laser Developments, Number 86, November - December 1986.

DTIC Science & Technology

1987-12-01

Korenev , M.S. 0. Synthesis of the sensitive element for a fiberoptic level transducer based on irregular light guide structures. TsNIITEIpriboro...Deposit, no. 3412-prD86, 9 p. (PRSUB, no. 12, 1986, 43). 687. Korenev , M.S. (). Analysis of the characteristics of bispiral conical sensing elements...TsNIITEIpriboro. Deposit, no. 3414-prD86, 8 p. (PRSUB, no. 12, 1986, 43). 688. Korenev , M.S. (). Discrete extrapolation algorithm to process measuring

Resonance line transfer calculations by doubling thin layers. I - Comparison with other techniques. II - The use of the R-parallel redistribution function. [planetary atmospheres

NASA Technical Reports Server (NTRS)

Yelle, Roger V.; Wallace, Lloyd

1989-01-01

A versatile and efficient technique for the solution of the resonance line scattering problem with frequency redistribution in planetary atmospheres is introduced. Similar to the doubling approach commonly used in monochromatic scattering problems, the technique has been extended to include the frequency dependence of the radiation field. Methods for solving problems with external or internal sources and coupled spectral lines are presented, along with comparison of some sample calculations with results from Monte Carlo and Feautrier techniques. The doubling technique has also been applied to the solution of resonance line scattering problems where the R-parallel redistribution function is appropriate, both neglecting and including polarization as developed by Yelle and Wallace (1989). With the constraint that the atmosphere is illuminated from the zenith, the only difficulty of consequence is that of performing precise frequency integrations over the line profiles. With that problem solved, it is no longer necessary to use the Monte Carlo method to solve this class of problem.

Modeling wet deposition of acid substances over the PRD region in China

NASA Astrophysics Data System (ADS)

Lu, Xingcheng; Fung, Jimmy Chi Hung; Wu, Dongwei

2015-12-01

The Pearl River Delta (PRD) region in southern China has suffered heavily from acid rain in the last 10 years due to the anthropogenic emission of sulfur dioxide and nitrogen dioxide. Several measurement-based studies about this issue have been conducted to analyze the chemical composition of precipitation in this area. However, no detailed, high resolution numerical simulation regarding this topic has ever been done in this region. In this study, the WRF-SMOKE-CMAQ system was applied to simulate the wet deposition of acid substances (SO42- and NO3-) in the PRD region from 2009 to 2011 with a resolution of 3 km. The simulation output agreed well with the observation data. Our results showed that Guangzhou was the city most affected by acid rain in this region. The ratio of non-sea-salt sulfate to nitrate indicated that the acid rain in this region belonged to the sulfate-nitrate mixed type. The source apportionment result suggests that point source and super regional source are the ones that contribute the pollutants most in the rain water over PRD Region. The sulfate and nitrate input to some reservoirs via wet deposition was also estimated based on the model simulation. Our results suggest that further cross-city cooperation and emission reduction are needed to further curb acid rain in this region.

Threshold of long-term survival of a coastal delphinid in anthropogenically degraded environment: Indo-Pacific humpback dolphins in Pearl River Delta.

PubMed

Karczmarski, Leszek; Huang, Shiang-Lin; Chan, Stephen C Y

2017-02-23

Defining demographic and ecological threshold of population persistence can assist in informing conservation management. We undertook such analyses for the Indo-Pacific humpback dolphin (Sousa chinensis) in the Pearl River Delta (PRD) region, southeast China. We use adult survival estimates for assessments of population status and annual rate of change. Our estimates indicate that, given a stationary population structure and minimal risk scenario, ~2000 individuals (minimum viable population in carrying capacity, MVP k ) can maintain the population persistence across 40 generations. However, under the current population trend (~2.5% decline/annum), the population is fast approaching its viability threshold and may soon face effects of demographic stochasticity. The population demographic trajectory and the minimum area of critical habitat (MACH) that could prevent stochastic extinction are both highly sensitive to fluctuations in adult survival. For a hypothetical stationary population, MACH should approximate 3000-km 2 . However, this estimate increases four-fold with a 5% increase of adult mortality and exceeds the size of PRD when calculated for the current population status. On the other hand, cumulatively all current MPAs within PRD fail to secure the minimum habitat requirement to accommodate sufficiently viable population size. Our findings indicate that the PRD population is deemed to become extinct unless effective conservation measures can rapidly reverse the current population trend.

Power-rate-distortion analysis for wireless video communication under energy constraint

NASA Astrophysics Data System (ADS)

He, Zhihai; Liang, Yongfang; Ahmad, Ishfaq

2004-01-01

In video coding and streaming over wireless communication network, the power-demanding video encoding operates on the mobile devices with limited energy supply. To analyze, control, and optimize the rate-distortion (R-D) behavior of the wireless video communication system under the energy constraint, we need to develop a power-rate-distortion (P-R-D) analysis framework, which extends the traditional R-D analysis by including another dimension, the power consumption. Specifically, in this paper, we analyze the encoding mechanism of typical video encoding systems and develop a parametric video encoding architecture which is fully scalable in computational complexity. Using dynamic voltage scaling (DVS), a hardware technology recently developed in CMOS circuits design, the complexity scalability can be translated into the power consumption scalability of the video encoder. We investigate the rate-distortion behaviors of the complexity control parameters and establish an analytic framework to explore the P-R-D behavior of the video encoding system. Both theoretically and experimentally, we show that, using this P-R-D model, the encoding system is able to automatically adjust its complexity control parameters to match the available energy supply of the mobile device while maximizing the picture quality. The P-R-D model provides a theoretical guideline for system design and performance optimization in wireless video communication under energy constraint, especially over the wireless video sensor network.

Estimated emissions of chlorofluorocarbons, hydrochlorofluorocarbons, and hydrofluorocarbons based on an interspecies correlation method in the Pearl River Delta region, China.

PubMed

Wu, Jing; Fang, Xuekun; Martin, Jonathan W; Zhai, Zihan; Su, Shenshen; Hu, Xia; Han, Jiarui; Lu, Sihua; Wang, Chen; Zhang, Jianbo; Hu, Jianxin

2014-02-01

Although many studies have been conducted in recent years on the emissions of chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), and hydrofluorocarbons (HFCs) at the large regional (such as East Asia) and national scales, relatively few studies have been conducted for cities or metropolitan areas. In this study, 192 air samples were collected in the Pearl River Delta (PRD) region of China in November 2010. The atmospheric mixing ratios of six halocarbons were analyzed, including trichlorofluoromethane (CFC-11, CCl3F), dichlorodifluoromethane (CFC-12, CCl2F2), monochlorodifluoromethane (HCFC-22, CHClF2), 1,1-dichloro-1-fluoroethane (HCFC-141b, CH3CCl2F), 1-dichloro-1,1-fluoroethane (HCFC-142b, CH3CClF2), and 1,1,1,2-tetrafluoroethane (HFC-134a, CH2FCF3), and their emissions were estimated based on an interspecies correlation method using HCFC-22 as the reference species. The results showed no significant change in the regional concentration and emission of CFC in the past 10years, suggesting that the continuous regional emission of CFC has had no significant effect on the CFC regional concentration in the PRD region. Concentrations and emissions of HCFCs and HFCs are significantly higher compared to previous research in the PRD region (P<0.05). The largest emission was for HCFC-22, most likely due to its substitution for CFC-12 in the industrial and commercial refrigeration subsector, and the rapid development of the room air-conditioner and extruded polystyrene subsectors. The PRD's ODP-weighted emissions of the target HCFCs provided 9% (7-12%) of the national emissions for the corresponding species. The PRD's GWP-weighted emissions of the target HCFCs and HFC-134a account for 10% (7-12%) and 8% (7-9%), respectively, of the national emissions for the corresponding species, and thus are important contributions to China's total emissions. © 2013 Elsevier B.V. All rights reserved.

Numerical simulations for the sources apportionment and control strategies of PM2.5 over Pearl River Delta, China, part I: Inventory and PM2.5 sources apportionment.

PubMed

Huang, Yeqi; Deng, Tao; Li, Zhenning; Wang, Nan; Yin, Chanqin; Wang, Shiqiang; Fan, Shaojia

2018-09-01

This article uses the WRF-CMAQ model to systematically study the source apportionment of PM 2.5 under typical meteorological conditions in the dry season (November 2010) in the Pearl River Delta (PRD). According to the geographical location and the relative magnitude of pollutant emission, Guangdong Province is divided into eight subdomains for source apportionment study. The Brute-Force Method (BFM) method was implemented to simulate the contribution from different regions to the PM 2.5 pollution in the PRD. Results show that the industrial sources accounted for the largest proportion. For emission species, the total amount of NO x and VOC in Guangdong Province, and NH 3 and VOC in Hunan Province are relatively larger. In Guangdong Province, the emission of SO 2 , NO x and VOC in the PRD are relatively larger, and the NH 3 emissions are higher outside the PRD. In northerly-controlled episodes, model simulations demonstrate that local emissions are important for PM 2.5 pollution in Guangzhou and Foshan. Meanwhile, emissions from Dongguan and Huizhou (DH), and out of Guangdong Province (SW) are important contributors for PM 2.5 pollution in Guangzhou. For PM 2.5 pollution in Foshan, emissions in Guangzhou and DH are the major contributors. In addition, high contribution ratio from DH only occurs in severe pollution periods. In southerly-controlled episode, contribution from the southern PRD increases. Local emissions and emissions from Shenzhen, DH, Zhuhai-Jiangmen-Zhongshan (ZJZ) are the major contributors. Regional contribution to the chemical compositions of PM 2.5 indicates that the sources of chemical components are similar to those of PM 2.5 . In particular, SO 4 2- is mainly sourced from emissions out of Guangdong Province, while the NO 3- and NH 4+ are more linked to agricultural emissions. Copyright © 2018 Elsevier B.V. All rights reserved.

Dose-Dependent Pulmonary Toxicity After Postoperative Intensity-Modulated Radiotherapy for Malignant Pleural Mesothelioma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rice, David C.; Smythe, W. Roy; Liao Zhongxing

Purpose: To determine the incidence of fatal pulmonary events after extrapleural pneumonectomy and hemithoracic intensity-modulated radiotherapy (IMRT) for malignant pleural mesothelioma. Methods and Materials: We retrospectively reviewed the records of 63 consecutive patients with malignant pleural mesothelioma who underwent extrapleural pneumonectomy and IMRT at University of Texas M. D. Anderson Cancer Center. The endpoints studied were pulmonary-related death (PRD) and non-cancer-related death within 6 months of IMRT. Results: Of the 63 patients, 23 (37%) had died within 6 months of IMRT (10 of recurrent cancer, 6 of pulmonary causes [pneumonia in 4 and pneumonitis in 2], and 7 of othermore » noncancer causes [pulmonary embolus in 2, sepsis after bronchopleural fistula in 1, and cause unknown but without pulmonary symptoms or recurrent disease in 4]). On univariate analysis, the factors that predicted for PRD were a lower preoperative ejection fraction (p = 0.021), absolute volume of lung spared at 10 Gy (p = 0.025), percentage of lung volume receiving {>=}20 Gy (V{sub 20}; p 0.002), and mean lung dose (p = 0.013). On multivariate analysis, only V{sub 20} was predictive of PRD (p = 0.017; odds ratio, 1.50; 95% confidence interval, 1.08-2.08) or non-cancer-related death (p = 0.033; odds ratio, 1.21; 95% confidence interval, 1.02-1.45). Conclusion: The results of our study have shown that fatal pulmonary toxicities were associated with radiation to the contralateral lung. V{sub 20} was the only independent determinant for risk of PRD or non-cancer-related death. The mean V{sub 20} of the non-PRD patients was considerably lower than that accepted during standard thoracic radiotherapy, implying that the V{sub 20} should be kept as low as possible after extrapleural pneumonectomy.« less

Sector-based VOCs emission factors and source profiles for the surface coating industry in the Pearl River Delta region of China.

PubMed

Zhong, Zhuangmin; Sha, Qing'e; Zheng, Junyu; Yuan, Zibing; Gao, Zongjiang; Ou, Jiamin; Zheng, Zhuoyun; Li, Cheng; Huang, Zhijiong

2017-04-01

Accurate depiction of VOCs emission characteristics is essential for the formulation of VOCs control strategies. As one of the continuous efforts in improving VOCs emission characterization in the Pearl River Delta (PRD) region, this study targeted on surface coating industry, the most important VOCs emission sources in the PRD. Sectors in analysis included shipbuilding coating, wood furniture coating, metal surface coating, plastic surface coating, automobile coating and fabric surface coating. Sector-based field measurement was conducted to characterize VOCs emission factors and source profiles in the PRD. It was found that the raw material-based VOCs emission factors for these six sectors ranged from 0.34 to 0.58kg VOCs per kg of raw materials (kg·kg -1 ) while the emission factors based on the production yield varied from 0.59kg to 13.72t VOCs for each production manufactured. VOCs emission factors of surface coating industry were therefore preferably calculated based on raw materials with low uncertainties. Source profiles differed greatly among different sectors. Aromatic was the largest group for shipbuilding coating, wood furniture coating, metal surface coating and automobile coating while the oxygenated VOCs (OVOCs) were the most abundant in the plastic and fabric surface coating sectors. The major species of aromatic VOCs in each of these six sectors were similar, mainly toluene and m/p-xylene, while the OVOCs varied among the different sectors. VOCs profiles in the three processes of auto industry, i.e., auto coating, auto drying and auto repairing, also showed large variations. The major species in these sectors in the PRD were similar with other places but the proportions of individual compounds were different. Some special components were also detected in the PRD region. This study highlighted the importance of updating local source profiles in a comprehensive and timely manner. Copyright © 2016 Elsevier B.V. All rights reserved.

A regional scale investigation on factors controlling the groundwater chemistry of various aquifers in a rapidly urbanized area: A case study of the Pearl River Delta.

PubMed

Huang, Guanxing; Liu, Chunyan; Sun, Jichao; Zhang, Ming; Jing, Jihong; Li, Liangping

2018-06-01

A growing population accompanied by urbanization has increased groundwater resource demands in the Pearl River Delta (PRD) area, southern China, and a comprehensive understanding of the groundwater chemistry in the PRD is necessary. The aims of this study were to investigate the groundwater chemistry in various aquifers in the PRD on a regional scale and to discuss the factors that control the groundwater chemistries of different types of aquifers. In addition, the effect of the expansion of construction land on the groundwater chemistry was also taken into consideration in this study. Nearly 400 groundwater samples were collected and fourteen chemical parameters were investigated. The results show that natural factors, such as seawater intrusions, are mainly responsible for the higher concentrations of total dissolved solids, Na + , Mg 2+ , K + , and Cl - , in granular aquifers than those in fissured and karst aquifers. Similarly, higher concentrations of NH 4 + , Fe and Mn in granular aquifers than those in the other two types of aquifers are mainly ascribed to natural reduction. In contrast, human activities, such as the continuous irrigation of river water, upon granular aquifer are mainly responsible for the higher concentrations of Ca 2+ and HCO 3 - in granular aquifers than those in other two types of aquifers. Urbanization and industrialization are the main driving forces for the frequently occurrences of NO 3 and SO 4 water types, respectively. Moreover, the number of water types in the PRD increased to 89 after the decades of urbanization. Factors that control groundwater chemistries in various aquifers were extracted. A four-factor model controlled the groundwater chemistry of granular aquifers, while two three-factor models controlled the groundwater chemistries of fissured and karst aquifers, respectively. The results of this study show that the expansion of construction land is a powerful driving force for the change of groundwater chemistry in the PRD. Copyright © 2017 Elsevier B.V. All rights reserved.

Landscape ecological security assessment based on projection pursuit in Pearl River Delta.

PubMed

Gao, Yang; Wu, Zhifeng; Lou, Quansheng; Huang, Huamei; Cheng, Jiong; Chen, Zhangli

2012-04-01

Regional landscape ecological security is an important issue for ecological security, and has a great influence on national security and social sustainable development. The Pearl River Delta (PRD) in southern China has experienced rapid economic development and intensive human activities in recent years. This study, based on landscape analysis, provides a method to discover the alteration of character among different landscape types and to understand the landscape ecological security status. Based on remotely sensed products of the Landsat 5 TM images in 1990 and the Landsat 7 ETM+ images in 2005, landscape classification maps of nine cities in the PRD were compiled by implementing Remote Sensing and Geographic Information System technology. Several indices, including aggregation, crush index, landscape shape index, Shannon's diversity index, landscape fragile index, and landscape security adjacent index, were applied to analyze spatial-temporal characteristics of landscape patterns in the PRD. A landscape ecological security index based on these outcomes was calculated by projection pursuit using genetic algorithm. The landscape ecological security of nine cities in the PRD was thus evaluated. The main results of this research are listed as follows: (1) from 1990 to 2005, the aggregation index, crush index, landscape shape index, and Shannon's diversity index of nine cities changed little in the PRD, while the landscape fragile index and landscape security adjacent index changed obviously. The landscape fragile index of nine cities showed a decreasing trend; however, the landscape security adjacent index has been increasing; (2) from 1990 to 2005, landscape ecology of the cities of Zhuhai and Huizhou maintained a good security situation. However, there was a relatively low value of ecological security in the cities of Dongguan and Foshan. Except for Foshan and Guangzhou, whose landscape ecological security situation were slightly improved, the cities had reduced values in landscape ecological security, with the most decreased number 0.52 in Zhaoqing. Results of this study offer important information for regional eco-construction and natural resource exploitation.

Depressed polymorphonuclear cell functions in periparturient cows that develop postpartum reproductive diseases.

PubMed

Islam, Rafiqul; Kumar, Harendra; Singh, Gyanendra; Krishnan, Binsila B; Dey, Sahadeb

2017-09-01

The study was planned to see if there is any important and significant changes in the PMN function in cows suffering from postpartum reproductive diseases (PRD). Blood sampling was done from 41 pregnant cows on 15 days prepartum (-15d), calving day (0d), 15 days (15d) and 30 days (30d) postpartum and thorough gynaecological examination was performed on 0d, 15d, 30d and 45d for diagnosis of PRD like retained placenta (RP), clinical metritis (CM), clinical endometritis (CE) and delayed involution of uterus (DIU). The heparinised blood was used for isolation of PMN leukocytes for estimation of superoxide (SO), hydrogen peroxide (H 2 O 2 ) and enzyme myeloperoxidase (MPO) activity in each group of cows. The SO production (ΔOD) was greater for normal (0.19 ± 0.05) than cows suffering from RP (-0.12 ± 0.09), CM (-0.15 ± 0.13) and CE (-0.07 ± 0.05) at -15d. The mean value was greater for normal cows (0.12) than the cows with PRD (0.05 to 0.9) at 30d. The H 2 O 2 production was greater for normal than cows with PRD at all sampling days and significantly greater than cows with RP and CE at 15d (p < 0.01) and 30d (P < 0.05). The MPO activity (μmol/1 × 10 7 ) was greater for normal (18.77 ± 1.27) than for RP (12.52 ± 2.57) and CM (11.31 ± 3.30) cows on 0d. The depressed capability of the PMN from the cows with PRD to produce SO, H 2 O 2 and MPO during the periparturient period indicated their association with the development of RP, CM and CE.

Monitoring Population Evolution in the Pearl River Delta from 2000 TO 2010

NASA Astrophysics Data System (ADS)

Yu, S.; Liu, F.; Zhang, Z.

2018-04-01

On behalf of more populous and developed regions in China, urban agglomerations have become important carries loading active economic activities and generous social benefits, and experienced sharper population increase, which results in great threat on local eco-environment construction. Therefore, exact and detailed population monitoring and analyzing, especially on the long sequence and multi frequency, is of great significance. The nighttime light time-series (NLT) products has been proven to be one of the most useful remotely sensed imagery to acquire persons at 1 km × 1 km scales. However, the existed problems, such as light saturation and blooming, greatly limit the accuracy of estimated results. Furthermore, it's difficult to spatialize population at km2 level due to the lack of basic data in non-census years. In order to solve all problems mentioned above, the populous Pearl River Delta was selected as the study area. A new residential extent extraction index (REEI) was proposed to solve light saturation and blooming problems. Population spatialization methods in census and non-census years were applied to acquire detailed population distribution from 2000 to 2010. Results showed the feasibility of the proposed methods in this work. During the decade, population was denser in the central PRD and sparser in the eastern, western and northern PRD. The speed of population increase was various in nine cities, but faster in 2000-2005 than 2005-2010.

A scale-invariant cellular-automata model for distributed seismicity

NASA Technical Reports Server (NTRS)

Barriere, Benoit; Turcotte, Donald L.

1991-01-01

In the standard cellular-automata model for a fault an element of stress is randomly added to a grid of boxes until a box has four elements, these are then redistributed to the adjacent boxes on the grid. The redistribution can result in one or more of these boxes having four or more elements in which case further redistributions are required. On the average added elements are lost from the edges of the grid. The model is modified so that the boxes have a scale-invariant distribution of sizes. The objective is to model a scale-invariant distribution of fault sizes. When a redistribution from a box occurs it is equivalent to a characteristic earthquake on the fault. A redistribution from a small box (a foreshock) can trigger an instability in a large box (the main shock). A redistribution from a large box always triggers many instabilities in the smaller boxes (aftershocks). The frequency-size statistics for both main shocks and aftershocks satisfy the Gutenberg-Richter relation with b = 0.835 for main shocks and b = 0.635 for aftershocks. Model foreshocks occur 28 percent of the time.

Mechanism of intermediate filament recognition by plakin repeat domains revealed by envoplakin targeting of vimentin

NASA Astrophysics Data System (ADS)

Fogl, Claudia; Mohammed, Fiyaz; Al-Jassar, Caezar; Jeeves, Mark; Knowles, Timothy J.; Rodriguez-Zamora, Penelope; White, Scott A.; Odintsova, Elena; Overduin, Michael; Chidgey, Martyn

2016-03-01

Plakin proteins form critical connections between cell junctions and the cytoskeleton; their disruption within epithelial and cardiac muscle cells cause skin-blistering diseases and cardiomyopathies. Envoplakin has a single plakin repeat domain (PRD) which recognizes intermediate filaments through an unresolved mechanism. Herein we report the crystal structure of envoplakin's complete PRD fold, revealing binding determinants within its electropositive binding groove. Four of its five internal repeats recognize negatively charged patches within vimentin via five basic determinants that are identified by nuclear magnetic resonance spectroscopy. Mutations of the Lys1901 or Arg1914 binding determinants delocalize heterodimeric envoplakin from intracellular vimentin and keratin filaments in cultured cells. Recognition of vimentin is abolished when its residues Asp112 or Asp119 are mutated. The latter slot intermediate filament rods into basic PRD domain grooves through electrosteric complementarity in a widely applicable mechanism. Together this reveals how plakin family members form dynamic linkages with cytoskeletal frameworks.

Chemical partitioning for the Co--Pr system: First-principles, experiments and energetic calculations to investigate the hard magnetic phase

DOE PAGES

Zhou, S. H.; Kramer, M. J.; Meng, F. Q.; ...

2015-11-14

Co 5Pr-D2 d is promising permanent magnet. Due to its peritectic formation feature, there is a synthetic challenge to produce single Co 5Pr-D2 d phase. The object of our study is to assess thermodynamic pathways for crystalline phases under far-from-equilibrium conditions by combining first-principles calculations and experimental measurements into a robust description of the thermodynamic behavior. The energetic calculations, temperature and time dependent phase selections are predicted under varying degrees of chemical partitioning. Our calculation to assess the chemical partitioning-temperatures indicates that the major magnetic compounds: Co 17Pr 2-α, Co 5Pr-D2 d, Co 19Pr 5-β, and Co 7Pr 2-χ formmore » from a congruent manner to eutectic reactions with decreasing cooling rate. The compositions of the compounds from these highly driven liquids can be far from equilibrium.« less

Characterizing and sourcing ambient PM2.5 over key emission regions in China III: Carbon isotope based source apportionment of black carbon

NASA Astrophysics Data System (ADS)

Yu, Kuangyou; Xing, Zhenyu; Huang, Xiaofeng; Deng, Junjun; Andersson, August; Fang, Wenzheng; Gustafsson, Örjan; Zhou, Jiabin; Du, Ke

2018-03-01

Regional haze over China has severe implications for air quality and regional climate. To effectively combat these effects the high uncertainties regarding the emissions from different sources needs to be reduced. In this paper, which is the third in a series on the sources of PM2.5 in pollution hotspot regions of China, we focus on the sources of black carbon aerosols (BC), using carbon isotope signatures. Four-season samples were collected at two key locations: Beijing-Tianjin-Hebei (BTH, part of Northern China plain), and the Pearl River Delta (PRD). We find that that fossil fuel combustion was the predominant source of BC in both BTH and PRD regions, accounting for 75 ± 5%. However, the contributions of what fossil fuel components were dominating differed significantly between BTH and PRD, and varied dramatically with seasons. Coal combustion is overall the all-important BC source in BTH, accounting for 46 ± 12% of the BC in BTH, with the maximum value (62%) found in winter. In contrast for the PRD region, liquid fossil fuel combustion (e.g., oil, diesel, and gasoline) is the dominant source of BC, with an annual mean value of 41 ± 15% and the maximum value of 55% found in winter. Region- and season-specific source apportionments are recommended to both accurately assess the climate impact of carbonaceous aerosol emissions and to effectively mitigate deteriorating air quality caused by carbonaceous aerosols.

Development and Testing of PRD-66 Hot Gas Filters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chambers, J.A.; Garnier, J.E.; McMahon, T. J.

1996-12-31

The overall objective of this program is to develop and commercialize PRD-66 hot gas filters for application in pressurized fluidized bed combustors (PFBC) and Integrated Gas Combined Cycle (IGCC) power generation systems. The work is being carried out in phases with the following specific objectives: 1. Demonstrate acceptable mechanical, chemical, and filtration properties in exposure tests. 2. Produce and qualify selected prototype design filter elements in high temperature high pressure (HTHP) simulated PFBC exposure tests. 3. (Option) Generate a manufacturing plan to support commercial scale-up. 4. (Option) Recommend process equipment upgrades and produce 50 candle filters. Since the beginning ofmore » this program, a parallel evaluation of DuPont Lanxide Composites Inc. (DLC) PRD-66 hot gas candle filters took place using AEP`s TIDD PFBC facility. Several PRD-66 filters experienced damage during the final testing phase at TIDD, after highly successful testing in earlier runs. During the past year, DLC has undertaken a study under this contract to understand the mechanism of damage sustained in TIDD Test Segment 5. DLC has formulated a hypothesis for the damage mechanism based on the available evidence, and verified that the damage mechanism is possible given the conditions known to exist in TIDD. Improvements to the filter design to eliminate the root cause of the failure have been undertaken. This report details DLC`s conclusions regarding the failure mechanism, the evidence supporting the conclusions, and steps being taken to eliminate the root cause.« less

A real-time ECG data compression and transmission algorithm for an e-health device.

PubMed

Lee, SangJoon; Kim, Jungkuk; Lee, Myoungho

2011-09-01

This paper introduces a real-time data compression and transmission algorithm between e-health terminals for a periodic ECGsignal. The proposed algorithm consists of five compression procedures and four reconstruction procedures. In order to evaluate the performance of the proposed algorithm, the algorithm was applied to all 48 recordings of MIT-BIH arrhythmia database, and the compress ratio (CR), percent root mean square difference (PRD), percent root mean square difference normalized (PRDN), rms, SNR, and quality score (QS) values were obtained. The result showed that the CR was 27.9:1 and the PRD was 2.93 on average for all 48 data instances with a 15% window size. In addition, the performance of the algorithm was compared to those of similar algorithms introduced recently by others. It was found that the proposed algorithm showed clearly superior performance in all 48 data instances at a compression ratio lower than 15:1, whereas it showed similar or slightly inferior PRD performance for a data compression ratio higher than 20:1. In light of the fact that the similarity with the original data becomes meaningless when the PRD is higher than 2, the proposed algorithm shows significantly better performance compared to the performance levels of other algorithms. Moreover, because the algorithm can compress and transmit data in real time, it can be served as an optimal biosignal data transmission method for limited bandwidth communication between e-health devices.

Use of Pressure-Redistributing Support Surfaces among Elderly Hip Fracture Patients across the Continuum of Care: Adherence to Pressure Ulcer Prevention Guidelines

ERIC Educational Resources Information Center

Baumgarten, Mona; Margolis, David; Orwig, Denise; Hawkes, William; Rich, Shayna; Langenberg, Patricia; Shardell, Michelle; Palmer, Mary H.; McArdle, Patrick; Sterling, Robert; Jones, Patricia S.; Magaziner, Jay

2010-01-01

Purpose: To estimate the frequency of use of pressure-redistributing support surfaces (PRSS) among hip fracture patients and to determine whether higher pressure ulcer risk is associated with greater PRSS use. Design and Methods: Patients (n = 658) aged [greater than or equal] 65 years who had surgery for hip fracture were examined by research…

High resolution of black carbon and organic carbon emissions in the Pearl River Delta region, China.

PubMed

Zheng, Junyu; He, Min; Shen, Xingling; Yin, Shasha; Yuan, Zibing

2012-11-01

A high-resolution regional black carbon (BC) and organic carbon (OC) emission inventory for the year 2009 was developed for the Pearl River Delta (PRD) region, China, based on the collected activity data and the latest emission factors. PM(2.5), BC and OC emissions were estimated to be 303 kt, 39 kt and 31 kt, respectively. Industrial processes were major contributing sources to PM(2.5) emissions. BC emissions were mainly from mobile sources, accounting for 65.0%, while 34.1% of OC emissions were from residential combustion. The primary OC/BC ratios for individual cities in the PRD region were dependent on the levels of economic development due to differences in source characteristics, with high ratios in the less developed cities and low ratios in the central and southern developed areas. The preliminary temporal profiles were established, showing the highest OC emissions in winter and relatively constant BC emissions throughout the year. The emissions were spatially allocated into grid cells with a resolution of 3 km × 3 km. Large amounts of BC emissions were distributed over the central-southern PRD city clusters, while OC emissions exhibited a relatively even spatial distribution due to the significant biomass burning emissions from the outlying area of the PRD region. Uncertainties in carbonaceous aerosol emissions were usually higher than in other primary pollutants like SO(2), NO(x), and PM(10). One of the key uncertainty sources was the emission factor, due to the absence of direct measurements of BC and OC emission rates. Copyright © 2012 Elsevier B.V. All rights reserved.

Thallium in flowering cabbage and lettuce: Potential health risks for local residents of the Pearl River Delta, South China.

PubMed

Yu, Huan-Yun; Chang, Chunying; Li, Fangbai; Wang, Qi; Chen, Manjia; Zhang, Jie

2018-06-08

Thallium (Tl), a rare metal, is universally present in the environment with high toxicity and accumulation. Thallium's behavior and fate require further study, especially in the Pearl River Delta (PRD), where severe Tl pollution incidents have occurred. One hundred two pairs of soil and flowering cabbage samples and 91 pairs of soil and lettuce samples were collected from typical farmland protection areas and vegetable bases across the PRD, South China. The contamination levels and spatial distributions of soil and vegetable (flowering cabbages and lettuces) Tl across the PRD were investigated. The relative contributions of soil properties to the bioavailability of Tl in vegetables were evaluated using random forest. Random forest is an accurate learning algorithm and is superior to conventional and correlation-based regression analyses. In addition, the health risks posed by Tl exposure via vegetable intake for residents of the PRD were assessed. The results indicated that rapidly available potassium (K) and total K in soil were the most important factors affecting Tl bioavailability, and the competitive effect of rapidly available K on vegetable Tl uptake was confirmed in this field study. Soil weathering also contributed substantially to Tl accumulation in the vegetables. In contrast, organic matter might not be a major factor affecting the mobility of Tl in most of the lettuce soils. Fe and manganese (Mn) oxides also contributed little to the bioavailability of Tl. A risk assessment suggested that the health risks for Tl exposure through flowering cabbage or lettuce intake were minimal. Copyright © 2018 Elsevier Ltd. All rights reserved.

Deficit irrigation and maturation stage influence quality and flavonoid composition of 'Valencia' orange fruit.

PubMed

Grilo, Filipa S; Di Stefano, Vita; Lo Bianco, Riccardo

2017-04-01

Effects of continuous deficit irrigation (DI) and partial rootzone drying (PRD) treatments (50% ETc) in comparison with full irrigation (CI, 100% ETc) were investigated during 'Valencia' orange fruit maturation. Ultra-high-performance liquid chromatography/high-resolution mass spectrometry was used to quantify hesperidin, narirutin, tangeritin, nobiletin, didymin and neoeriocitrin in the fruit juice and peel. No significant effect of irrigation was found on yield, juice soluble solids or acidity. Juice color was not influenced by irrigation or harvest date, whereas peel color increased during maturation and was more pronounced in CI and PRD fruits. Juice acidity reached a peak in May, while soluble solids increased linearly throughout maturation. Hesperidin was the major flavanone detected during maturation, with concentrations 200-fold higher in the fruit peel than in the juice. In the peel, narirutin, didymin and neoeriocitrin decreased while hesperidin, nobiletin and tangeritin increased with maturation. Narirutin synthesis in the orange fruit was insensitive to irrigation strategy. In fruit peels, PRD and DI induced the decline of hesperidin, nobiletin and tangeritin only in June, whereas in the juice, deficit irrigation treatments induced an increase in hesperidin and didymin. These results suggest that deficit irrigation, in particular the conditions imposed with PRD, may cause a significant accumulation shift of total flavonoids from the fruit peel into the juice, with a positive impact on juice quality and nutritional value. Fruit compositional changes during maturation also suggest that late harvest can improve fruit palatability and nutritional quality under the cultural and environmental conditions of this study. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Virus and bacteria transport in a sandy aquifer, Cape Cod, MA

USGS Publications Warehouse

Bales, Roger C.; Li, Shimin; Maguire, Kimberly M.; Yahya, Moyasar T.; Gerba, Charles P.; Harvey, Ronald W.

1995-01-01

Transport of the bacteriophage PRD-1, bacteria, and latex microspheres was studied in a sandy aquifer under natural-gradient conditions. The field injection was carried out at the U.S. Geological Survey's Toxic Substances Hydrology research site on Cape Cod. The three colloids and a salt tracer (Br−) moved along the same path. There was significant attenuation of the phage, with PRD-1 peak concentrations less than 0.001 percent of Br− peaks 6 m from the source; but the low detection limit (one per ml) enabled tracking movement of the PRD-1 plume for 12 m downgradient over the 25-day experiment. Attenuation of phage was apparently due to retention on soil particles (adsorption). Attenuation of bacteria and microspheres was less, with peak concentrations 6 m from the source on the order of 10 and 0.4 percent of Br−, respectively. Injection of a high-pH pulse of water 20 days into the experiment resulted in significant remobilization of retained phage, demonstrating that attached phage remained viable, and that PRD-1 attachment to and detachment from the sandy soil particles was highly pH dependent. Phage behavior in this experiment, i.e. attenuation at pH 5.7 and rapid resuspension at pH 6–8, was consistent with that observed previously in laboratory column studies. Results illustrate that biocolloids travel in a fairly narrow plume in sandy (relatively homogeneous) media, with virus concentrations dropping below detection limit several meters away from the source; bacteria concentrations above detection limits can persist over longer distances.

The correlation between dental calculus and disturbed mineral metabolism in paediatric patients with chronic kidney disease.

PubMed

Davidovich, Esti; Davidovits, Miriam; Peretz, Benny; Shapira, Joseph; Aframian, Doron J

2009-08-01

Vascular calcifications have been documented in children with end-stage renal disease. However, only a few reports have described abundant dental calculus formation in children suffering from chronic kidney disease (CKD). Moreover, dental calculus scores (DCS) and their correlation with renal disease severity have not been studied. DCS in 74 young CKD patients were evaluated: 25 pre-dialytic (PrD), 18 on dialysis (D) and 31 with transplants (T) compared to 32 healthy participants (C). Saliva and serum analysis included creatinine (Cr), urea (U), calcium (Ca), phosphorous (P), magnesium (Mg) as well as intraoral pH levels. All patient groups presented high DCS. DCS and pH levels were higher in the D group with a positive correlation between pH and lower incisor DCS (r = 0.56, P = 0.017). The highest salivary Ca was found in the PrD group. Salivary P in the PrD group was found to be higher than in the T and C groups. The lowest salivary Mg was found in the D group while the highest salivary Ca x P product was found in the PrD group. In all patient groups, salivary U was higher than in the C group with a 2.5-fold increase in the D group. Salivary Cr resembled the U salivary concentrations. Alterations in salivary Ca, P, Mg, U, Cr and intraoral pH levels were observed in the patient groups. DCS correlated with renal disease severity and therefore may be a reflection of other tissue calcification pathologies found in these patients.

Variability of ozone depleting substances as an indication of emissions in the Pearl River Delta, China

NASA Astrophysics Data System (ADS)

Chang, Chih-Chung; Lai, Cheng-Hsun; Wang, Chieh-Heng; Liu, Ying; Shao, Min; Zhang, Yuanhang; Wang, Jia-Lin

The continued production and consumption of five major chlorocarbons, i.e., CFC-11 (CCl 3F), CFC-12 (CCl 2F 2), CFC-113 (CCl 2FCClF 2), CH 3CCl 3, and CCl 4, as allowed by developing nations including China under the Montreal Protocol, were assessed by a method employing concentration variability. Measurements of the five ozone depleting substances (ODS) were measured in downtown Guangzhou and a rural site in the Pearl River Delta (PRD), China by both in situ and flask measurements. In order to post a contrast to PRD with a referencing environment of minimal emissions, in situ measurements were also conducted in Taipei, Taiwan, where a decade long phase-out of CFCs has been implemented. In general, the variability of chlorocarbons in the PRD sites was significantly greater than that of Taipei. While the abundance of the five ODSs in Taipei was relatively uniform with a relative standard deviation (RSD) varying between 3% and 16%, their variability in PRD with the exception of CFC-113 was significantly more pronounced, clearly indicating the significant usage of ODSs. The variability of CFC-113 in both cities, however, was nearly indiscernible from the instrumental precision, suggesting little usage of CFC-113 in China. Methyl chloroform in Guangzhou exhibited a strong link to solvent evaporation as it showed a tight correlation with ambient toluene. Alarmingly, CCl 4 was the most variable of the five major chlorocarbons in Guangzhou, which should arouse a serious concern for public health due to its carcinogenicity.

Humpback Dolphins in Hong Kong and the Pearl River Delta: Status, Threats and Conservation Challenges.

PubMed

Karczmarski, Leszek; Huang, Shiang-Lin; Or, Carmen K M; Gui, Duan; Chan, Stephen C Y; Lin, Wenzhi; Porter, Lindsay; Wong, Wai-Ho; Zheng, Ruiqiang; Ho, Yuen-Wa; Chui, Scott Y S; Tiongson, Angelico Jose C; Mo, Yaqian; Chang, Wei-Lun; Kwok, John H W; Tang, Ricky W K; Lee, Andy T L; Yiu, Sze-Wing; Keith, Mark; Gailey, Glenn; Wu, Yuping

2016-01-01

In coastal waters of the Pearl River Delta (PRD) region, the Indo-Pacific humpback dolphin (Sousa chinensis) is thought to number approximately 2500 individuals. Given these figures, the putative PRD population may appear strong enough to resist demographic stochasticity and environmental pressures. However, living in close proximity to the world's busiest seaport/airport and several densely populated urban centres with major coastal infrastructural developments comes with challenges to the long-term survival of these animals. There are few other small cetacean populations that face the range and intensity of human-induced pressures as those present in the PRD and current protection measures are severely inadequate. Recent mark-recapture analyses of the animals in Hong Kong waters indicate that in the past two decades the population parameters have not been well understood, and spatial analyses show that only a very small proportion of the dolphins' key habitats are given any form of protection. All current marine protected areas within the PRD fail to meet a minimum habitat requirement that could facilitate the population's long-term persistence. Demographic models indicate a continuous decline of 2.5% per annum, a rate at which the population is likely to drop below the demographic threshold within two generations and lose 74% of the current numbers within the lifespan of three generations. In Hong Kong, the case of humpback dolphins represents a particularly explicit example of inadequate management where a complete revision of the fundamental approach to conservation management is urgently needed. © 2016 Elsevier Ltd All rights reserved.

Evaluation of the factors controlling the time-dependent inactivation rate coefficients of bacteriophage MS2 and PRD1

USGS Publications Warehouse

Anders, R.; Chrysikopoulos, C.V.

2006-01-01

Static and dynamic batch experiments were conducted to study the effects of temperature and the presence of sand on the inactivation of bacteriophage MS2 and PRD1. The experimental data suggested that the inactivation process can be satisfactorily represented by a pseudo-first-order expression with time-dependent rate coefficients. The time-dependent rate coefficients were used to determine pertinent thermodynamic properties required for the analysis of the molecular processes involved in the inactivation of each bacteriophage. A combination of high temperature and the presence of sand appears to produce the greatest disruption to the surrounding protein coat of MS2. However, the lower activation energies for PRD1 indicate a weaker dependence of the inactivation rate on temperature. Instead, the presence of air-liquid and air-solid interfaces appears to produce the greatest damage to specific viral components that are related to infection. These results indicate the importance of using thermodynamic parameters based on the time-dependent inactivation model to better predict the inactivation of viruses in groundwater. ?? 2006 American Chemical Society.

Improving single-molecule FRET measurements by confining molecules in nanopipettes

NASA Astrophysics Data System (ADS)

Vogelsang, J.; Doose, S.; Sauer, M.; Tinnefeld, P.

2007-07-01

In recent years Fluorescence Resonance Energy Transfer (FRET) has been widely used to determine distances, observe distance dynamics, and monitor molecular binding at the single-molecule level. A basic constraint of single-molecule FRET studies is the limited distance resolution owing to low photon statistics. We demonstrate that by confining molecules in nanopipettes (50-100 nm diameter) smFRET can be measured with improved photon statistics reducing the width of FRET proximity ratio distributions (PRD). This increase in distance resolution makes it possible to reveal subpopulations and dynamics in biomolecular complexes. Our data indicate that the width of PRD is not only determined by photon statistics (shot noise) and distance distributions between the chromophores but that photoinduced dark states of the acceptor also contribute to the PRD width. Furthermore, acceptor dark states such as triplet states influence the accuracy of determined mean FRET values. In this context, we present a strategy for the correction of the shift of the mean PR that is related to triplet induced blinking of the acceptor using reference FCS measurements.

Public health and medical care for the world's factory: China's Pearl River Delta Region.

PubMed

Fabre, Guilhem; Rodwin, Victor G

2011-10-04

While the growth of urbanization, worldwide, has improved the lives of migrants from the hinterland, it also raises health risks related to population density, concentrated poverty and the transmission of infectious disease. Will megacity regions evolve into socially infected breeding grounds for the rapid transmission of disease, or can they become critical spatial entities for the protection and promotion of population health? We address this question for the Pearl River Delta Region (PRD) based on recent data from Chinese sources, and on the experience of how New York, Greater London, Tokyo and Paris have grappled with the challenges of protecting population health and providing their populations with access to health care services. In some respects, there are some important lessons from comparative experience for PRD, notably the importance of covering the entire population for health care services and targeting special programs for those at highest risk for disease. In other respects, PRD's growth rate and sheer scale make it a unique megacity region that already faces new challenges and will require new solutions.

The Small Viral Membrane-Associated Protein P32 Is Involved in Bacteriophage PRD1 DNA Entry

PubMed Central

Grahn, A. Marika; Daugelavičius, Rimantas; Bamford, Dennis H.

2002-01-01

The lipid-containing bacteriophage PRD1 infects a variety of gram-negative cells by injecting its linear double-stranded DNA genome into the host cell cytoplasm, while the protein capsid is left outside. The virus membrane and several structural proteins are involved in phage DNA entry. In this work we identified a new infectivity protein of PRD1. Disruption of gene XXXII resulted in a mutant phenotype defective in phage reproduction. The absence of the protein P32 did not compromise the particle assembly but led to a defect in phage DNA injection. In P32-deficient particles the phage membrane is unable to undergo a structural transformation from a spherical to a tubular form. Since P32− particles are able to increase the permeability of the host cell envelope to a degree comparable to that found with wild-type particles, we suggest that the tail-tube formation is needed to eject the DNA from the phage particle rather than to reach the host cell interior. PMID:11967303

Transformation of apparent ocean wave spectra observed from an aircraft sensor platform

NASA Technical Reports Server (NTRS)

Poole, L. R.

1976-01-01

The problem considered was transformation of a unidirectional apparent ocean wave spectrum observed from an aircraft sensor platform into the true spectrum that would be observed from a stationary platform. Spectral transformation equations were developed in terms of the linear wave dispersion relationship and the wave group speed. An iterative solution to the equations was outlined and used to transform reference theoretical apparent spectra for several assumed values of average water depth. Results show that changing the average water depth leads to a redistribution of energy density among the various frequency bands of the transformed spectrum. This redistribution is most severe when much of the energy density is expected, a priori, to reside at relatively low true frequencies.

Bronchopulmonary Dysplasia and Perinatal Characteristics Predict 1-Year Respiratory Outcomes in Newborns Born at Extremely Low Gestational Age: A Prospective Cohort Study.

PubMed

Keller, Roberta L; Feng, Rui; DeMauro, Sara B; Ferkol, Thomas; Hardie, William; Rogers, Elizabeth E; Stevens, Timothy P; Voynow, Judith A; Bellamy, Scarlett L; Shaw, Pamela A; Moore, Paul E

2017-08-01

To assess the utility of clinical predictors of persistent respiratory morbidity in extremely low gestational age newborns (ELGANs). We enrolled ELGANs (<29 weeks' gestation) at ≤7 postnatal days and collected antenatal and neonatal clinical data through 36 weeks' postmenstrual age. We surveyed caregivers at 3, 6, 9, and 12 months' corrected age to identify postdischarge respiratory morbidity, defined as hospitalization, home support (oxygen, tracheostomy, ventilation), medications, or symptoms (cough/wheeze). Infants were classified as having postprematurity respiratory disease (PRD, the primary study outcome) if respiratory morbidity persisted over ≥2 questionnaires. Infants were classified with severe respiratory morbidity if there were multiple hospitalizations, exposure to systemic steroids or pulmonary vasodilators, home oxygen after 3 months or mechanical ventilation, or symptoms despite inhaled corticosteroids. Mixed-effects models generated with data available at 1 day (perinatal) and 36 weeks' postmenstrual age were assessed for predictive accuracy. Of 724 infants (918 ± 234 g, 26.7 ± 1.4 weeks' gestational age) classified for the primary outcome, 68.6% had PRD; 245 of 704 (34.8%) were classified as severe. Male sex, intrauterine growth restriction, maternal smoking, race/ethnicity, intubation at birth, and public insurance were retained in perinatal and 36-week models for both PRD and respiratory morbidity severity. The perinatal model accurately predicted PRD (c-statistic 0.858). Neither the 36-week model nor the addition of bronchopulmonary dysplasia to the perinatal model improved accuracy (0.856, 0.860); c-statistic for BPD alone was 0.907. Both bronchopulmonary dysplasia and perinatal clinical data accurately identify ELGANs at risk for persistent and severe respiratory morbidity at 1 year. ClinicalTrials.gov: NCT01435187. Copyright © 2017 Elsevier Inc. All rights reserved.

Sectorial Water Use Trends in the Urbanizing Pearl River Delta, China

PubMed Central

Yao, Mingtian; Werners, Saskia E.; Hutjes, Ronald W. A.; Kabat, Pavel; Huang, Heqing

2015-01-01

Assessing and managing water use is crucial for supporting sustainable river basin management and regional development. The first consistent and comprehensive assessment of sectorial water use in the Pearl River Delta (PRD) is presented by analysing homogenized annual water use data from 2000 to 2010 in relation to socio economic statistics for the same period. An abstraction of water use, using the concept of water use intensity, and based on equations inspired by those used in global water resource models, is developed to explore the driving forces underlying water use changes in domestic, industrial and agricultural sectors. We do this at both the level of the region as a whole, as well as for the nine cities that constitute the PRD separately. We find that, despite strong population and economic growth, the PRD managed to stabilize its absolute water use by significant improvements in industrial water use intensities, and early stabilisation of domestic water use intensities. Results reveal large internal differentiation of sectorial water use among the cities in this region, with industrial water use intensity varying from -80 to +95% and domestic water use intensity by +/- 30% compared to the PRD average. In general, per capita water use is highest in the cities that industrialised first. Yet, all cities except Guangzhou are expected to approach a saturation value of per capita water use much below what is suggested in recent global studies. Therefore, existing global assessments probably have overestimated future domestic water use in developing countries. Although scarce and uncertain input data and model limitations lead to a high level of uncertainty, the presented conceptualization of water use is useful in exploring the underlying driving forces of water use trends. PMID:25714731

Day 3 thyroglobulin ≤ 1 ng/ml after recombinant human TSH just prior to radioactive iodine is predictive of low risk for persistent/recurrent disease in patients with papillary thyroid carcinoma.

PubMed

Rosario, Pedro W; Siman, Thássio Leonardo; Calsolari, Maria R

2015-05-01

We evaluated the negative predictive value (NPV) of thyroglobulin obtained 24 h after the second recombinant human TSH (rhTSH) ampoule (Tg-D3), before ablation with (131)I, for persistent/recurrent disease (PRD) in low/intermediate risk patients with papillary thyroid carcinoma. One hundred and one patients with Tg-D3 ≤ 1 ng/ml without anti-Tg antibodies (TgAb) were selected. Post-therapy whole-body scanning was negative for metastases in 98 (97 %) patients, and three patients showed discrete ectopic cervical uptake, but no corresponding disease was detected by neck ultrasound or computed tomography. One year after ablation, 98 (97 %) patients were free of the disease. Three patients had stimulated Tg >1 ng/ml, but no metastases were detected by the imaging methods. During follow-up (median 50 months), tumor recurrence was observed in only one patient. Thus, the NPV of Tg-D3 ≤ 1 ng/ml for PRD was 99 %. Among the 101 patients with Tg-D3 ≤ 1 ng/ml, Tg obtained 48 h after ablation (Tg-D5) continued to be ≤ 1 ng/ml in 56, and 45 had Tg-D5 >1 ng/ml. None of these 45 patients had PRD. In conclusion, Tg-D3 ≤ 1 ng/ml had a high NPV for PRD in patients without TgAb or known persistent disease and who are not at high risk. In these patients, Tg-D5 >1 ng/ml is more likely to reflect actinic damage to the remnant thyroid tissue rather than persistence of significant normal or tumor tissue.

Accounting for sap flow from different parts of the root system improves the prediction of xylem ABA concentration in plants grown with heterogeneous soil moisture.

PubMed

Dodd, Ian C; Egea, Gregorio; Davies, William J

2008-01-01

When soil moisture is heterogeneous, sap flow from, and ABA status of, different parts of the root system impact on leaf xylem ABA concentration ([X-ABA]leaf). The robustness of a model for predicting [X-ABA]leaf was assessed. 'Two root-one shoot' grafted sunflower (Helianthus annuus L.) plants received either deficit irrigation (DI, each root system received the same irrigation volumes) or partial rootzone drying (PRD, only one root system was watered and the other dried the soil). Irrespective of whether relative sap flow was assessed using sap flow sensors in vivo or by pressurization of de-topped roots, each root system contributed similarly to total sap flow during DI, while sap flow from roots in drying soil declined linearly with soil water potential (Psisoil) during PRD. Although Psisoil of the irrigated pot determined the threshold Psisoil at which sap flow from roots in drying soil decreased, the slope of this decrease was independent of the wet pot Psisoil. Irrespective of whether sap was collected from the wet or dry root system of PRD plants, or a DI plant, root xylem ABA concentration increased as Psisoil declined. The model, which weighted ABA contributions of each root system according to the sap flow from each, almost perfectly explained [X-ABA] immediately above the graft union. That the model overestimated measured [X-ABA]leaf may result from changes in [X-ABA] along the transport pathway or an artefact of collecting xylem sap from detached leaves. The implications of declining sap flow through partially dry roots during PRD for the control of stomatal behaviour and irrigation scheduling are discussed.

Dynamic Localization of a Transcription Factor in Bacillus subtilis: the LicT Antiterminator Relocalizes in Response to Inducer Availability

PubMed Central

Rothe, Fabian M.; Wrede, Christoph; Lehnik-Habrink, Martin; Görke, Boris

2013-01-01

Bacillus subtilis transports β-glucosides such as salicin by a dedicated phosphotransferase system (PTS). The expression of the β-glucoside permease BglP is induced in the presence of the substrate salicin, and this induction requires the binding of the antiterminator protein LicT to a specific RNA target in the 5′ region of the bglP mRNA to prevent the formation of a transcription terminator. LicT is composed of an N-terminal RNA-binding domain and two consecutive PTS regulation domains, PRD1 and PRD2. In the absence of salicin, LicT is phosphorylated on PRD1 by BglP and thereby inactivated. In the presence of the inducer, the phosphate group from PRD1 is transferred back to BglP and consequently to the incoming substrate, resulting in the activation of LicT. In this study, we have investigated the intracellular localization of LicT. While the protein was evenly distributed in the cell in the absence of the inducer, we observed a subpolar localization of LicT if salicin was present in the medium. Upon addition or removal of the inducer, LicT rapidly relocalized in the cells. This dynamic relocalization did not depend on the binding of LicT to its RNA target sites, since the localization pattern was not affected by deletion of all LicT binding sites. In contrast, experiments with mutants affected in the PTS components as well as mutations of the LicT phosphorylation sites revealed that phosphorylation of LicT by the PTS components plays a major role in the control of the subcellular localization of this RNA-binding transcription factor. PMID:23475962

Single-shot antithymocyte globuline and daclizumab induction in simultaneous pancreas and kidney transplant recipient: three-year results.

PubMed

Schulz, T; Flecken, M; Kapischke, M; Busing, M

2005-05-01

Since 1996, preoperative single-shot dose antithymocyte globuline (ATG) with prednisolone (PRD), mycophenolate mofetile (MMF), and tacrolimus (TAC) is the favorite induction therapy in our center. In a series of 25 first simultaneous pancreas and kidney transplant (SPK) recipients, 5 doses of daclizumab were administered in addition to standard induction. Here we present our 3-year experience. Immunosuppression was started prior to reperfusion consisting of daclizumab (1 mg/kg body weight [bw]), ATG (4-6 mg/kg bw) and 250 mg PRD. After surgery, PRD was reduced gradually, TAC trough levels were between 8-15 ng/mL, MMF was given twice daily (2-3 g/d) as well as 4 further doses dacilzumab every 14 days. After 3 years, patient, pancreas, and kidney graft survival rates are 100%, 84%, and 92%, respectively. Four pancreas grafts were lost (chronic allograft dysfunction, n = 2; recurrent abdominal infection, n = 1; acute rejection [AR] without treatment, n = 1). Both patients suffering from severe infection and untreated AR lost their kidney graft too. During the first 3 months after SPK, 3 AR episodes were observed in 2 patients (8%). After a 3-year period, 8 AR episodes occurred in 7 recipients (28%). AR was treated using PRD (n = 5) or ATG (n = 1). In 1 case, immunosuppression was switched from TAC to sirolimus successfully. Overall, 8 AR episodes occurred in 7 patients (28%) during the first 3 years after SPK. One severe infection led to graft lost 13 months after SPK. In this series, the combination of ATG and daclizumab prevented AR episodes, successfully providing considerable 3-year survival rates.

Characteristics of inorganic aerosol formation over ammonia-poor and ammonia-rich areas in the Pearl River Delta region, China

NASA Astrophysics Data System (ADS)

Yin, Shasha; Huang, Zhijiong; Zheng, Junyu; Huang, Xiaobo; Chen, Duohong; Tan, Haobo

2018-03-01

A well-evaluated Comprehensive Air quality Model with extensions (CAMx) was used to simulate concentrations of secondary inorganic aerosols in fine particulate matter (PM2.5) over Pearl River Delta (PRD) region during two separate months (April and October) in 2013. An indicator of adjusted gas ratio (AdjGR) was used to characterize PM chemistry under both NH3-poor (NP) and NH3-rich (NR) conditions as well as to identify their respective spatiotemporal patterns at different PM2.5 levels. The results were as follows: (1) Based on both observed molar ratio of [NH4+]/[SO42-] and modeled AdjGR, NR and NP conditions exhibited diurnal, daily, and seasonal variations. (2) A larger area in PRD had NP conditions over the two months when pollution was apparent; this NP region tended to occur downwind of PRD in October and the central region of PRD in April, with high PM2.5 concentrations in both. (3) This wider NP distribution could be related to higher nitrogen oxidation ratio (NOR), with more NOx converting to nitrate. Under conditions of higher pollution, there were relative lower degree of sulfate neutralization (DSN) and particle neutralization ratio (PNR). This supports the claim that NH3 may not be fully neutralized by SO42-. (4) Modeled AdjGR displayed clear hourly variations, with the lowest levels occurring in the afternoon. Reducing NH3 emission is not as efficient as NOx at increasing evening nitrate concentrations. (5) To mitigate PM2.5 pollution even further, a greater reduction of NH3 should be suggested in chemical regions transiting to NR condition when there are lower SO2 and NOx emissions.

Final Technical Report of the project "Controlling Quantum Information by Quantum Correlations"

DOE Office of Scientific and Technical Information (OSTI.GOV)

Girolami, Davide

The report describes hypotheses, aims, methods and results of the project 20170675PRD2, “Controlling Quantum Information by Quantum Correlations”, which has been run from July 31, 2017 to January 7, 2018. The technical work has been performed by Director’s Fellow Davide Girolami of the T-4 Division, Physics of Condensed Matter and Complex Systems, under the supervision of Wojciech Zurek (T-4), Lukasz Cincio (T-4), and Marcus Daniels (CCS-7). The project ended as Davide Girolami has been converted to J. R. Oppenheimer Fellow to work on the project 20180702PRD1, “Optimal Control of Quantum Machines”, started on January 8, 2018.

Immunosuppressive Interactions among Calcium Channel Antagonists and Selected Corticosteroids and Macrolides Using Human whole Blood Lymphocytes

PubMed Central

Chow, Fung-Sing; Jusko, William J.

2014-01-01

Summary The immunosuppressive interactions of calcium channel antagonists [diltiazem (Dil), verapamil (Ver) and nifedipine (Nif)], with corticosteroids [methylprednisolone (Mpl), prednisolone (Prd)], and macrolides [tacrolimus (Tac) and sirolnnus (Sir)] were examined in human whole blood lymphocyte cultures. Gender-related differences in responses in the interactions between these drug classes were studied using blood from 6 males and 6 females. The nature and intensity of interactions were determined using an extended Loewe additivity model. All immunosuppressants exhibited higher potency than the calcium channel antagonists with mean IC50 values of: Dil (mM)Ver (mM)Nif (mM)Mpl (nM)Prd (nM)Tac (nM)Sir (nM)Male13541.921312.118.6150327Female11431.847.44.68.8111106 Gender-related differences in responses to Mpl and Prd were observed while the others were not significant. Additive interactions were found among calcium channel antagonists and corticosteroids. Significant synergistic interactions were observed between calcium channel antagonists and tacrolimus and sirolimus, although these are unlikely to be of clinical importance. These studies demonstrate diverse drug interactions in the examination of an important array of immunosuppressant drug combinations. PMID:15681895

Overview on the Air Pollution Issues of the City Clusters in China and its Control Strategies

NASA Astrophysics Data System (ADS)

Tang, X.

2007-12-01

Mega-cities in China, such as Beijing, Guangzhou, Shenzhen, and Shanghai are located in three large city clusters, Bo-Hai Bay surrounding area, Pearl River Delta (PRD) and Yangtze River Delta. Like the rest of the coastal regions in China, these mega-cities have been experiencing fast economic developments and consequently serious environmental pollution. Air pollution in those areas is characterized by concurrent occurrence of high concentrations of multiple primary pollutants and secondary pollutants, which lead to the development of "air pollution complex" (perhaps typically Chinese) problem. Several campaigns of field experiments covering the regions such as PRD and Beijing City with surrounding areas have been conducted critically to understand the chemical and physical processes leading to the formation of regional scale air pollution since 2004. Some policy-relevant suggestions for air quality attainment have been made after these campaigns, specially the attainment of air quality during 2008 Beijing Olympic game, which has been attracted as an important concern worldwide. A scientific field campaign was conducted during August of 2007 for testing the control strategies suggested for air quality attainment in 2008-Olympic. An overview of the results of PRD and Beijing Campaigns will be presented.

Characterization of submicron aerosols at a rural site in Pearl River Delta of China using an Aerodyne High-Resolution Aerosol Mass Spectrometer

NASA Astrophysics Data System (ADS)

Huang, X.-F.; He, L.-Y.; Hu, M.; Canagaratna, M. R.; Kroll, J. H.; Ng, N. L.; Zhang, Y.-H.; Lin, Y.; Xue, L.; Sun, T.-L.; Liu, X.-G.; Shao, M.; Jayne, J. T.; Worsnop, D. R.

2010-11-01

The Pearl River Delta (PRD) region in South China is one of the most economically developed regions in China, but it is also noted for its severe air pollution due to industrial/metropolitan emissions. In order to continuously improve the understanding and quantification of air pollution in this region, an intensive campaign was executed in PRD during October-November 2008. Here, we report and analyze Aerodyne High-Resolution Aerosol Mass Spectrometer measurements at Kaiping, a rural site downwind of the highly-polluted central PRD area, to characterize the general features of submicron particulate pollution in the regional air. The mean measured PM1 mass concentration was 33.1 ± 18.1 μg m-3 during the campaign and composed of organic matter (33.8%), sulfate (33.7%), ammonium (14.0%), nitrate (10.7%), black carbon (6.7%), and chloride (1.1%), which is characterized by high fractions of inorganic ions due to huge emissions of SO2 and NOx in PRD. The average size distributions of the species (except BC) were all dominated by an accumulation mode peaking at ~450 nm in vacuum aerodynamic diameter. Calculations based on high-resolution organic mass spectra indicate that C, H, O, and N on average contributed 56.6, 7.0, 35.1, and 1.3% to the total organic mass, respectively, corresponding to an organic matter mass to organic carbon mass ratio (OM/OC) of 1.77 ± 0.08. Based on the high-resolution organic mass spectral dataset observed, Positive Matrix Factorization (PMF) analysis differentiated the organic aerosol into three components, i.e., biomass burning (BBOA) and two oxygenated (LV-OOA and SV-OOA) organic aerosols, which on average accounted for 24.5, 39.6 and 35.8% of the total organic mass, respectively. The BBOA showed strong features of biomass burning emissions and has been mainly attributed to field rice straw burning after harvest. The LV-OOA and SV-OOA were found to correspond to more aged (and thus less-volatile) and fresher (and semi-volatile) secondary organic aerosol, respectively. Analysis of meteorological influence supported that regional transport from the central PRD area was the major origin of the PM1 components observed at the Kaiping site.

Preparation of Graphene Oxide and Its Mechanism in Promoting Tomato Roots Growth.

PubMed

Jiao, Jingzhi; Cheng, Fan; Zhang, Xuekun; Xie, Lingli; Li, Zhiyang; Yuan, Chengfei; Xu, Benbo; Zhang, Liming

2016-04-01

Graphene oxide is a new kind of nanomaterial. The graphene oxide was prepared and its quality detected by atomic force microscopy (AFM) and transmission electron microscopy (TEM), for better understanding of effects of the nanomaterial on plants. Wild type. (WT) tomato (Solanum lycopersicum) germplasm 'New Yorker' and corresponding transgenic plants (Prd29A::LeNCED1) were treated with prepared graphene oxide. 9-cis-epoxycarotenoid dioxygenase (NCED) is a key gene for ABA biosynthesis and overexpression of the NCED resulted in ABA accumulation and higher drought tolerance. Seminal root length in the WT tomato was longer than that in the control samples when the seedlings were treated with 20 mg/L graphene oxide for 15 days. In contrast, the same treatment resulted in shorter seminal root length in the transgenic plants compared with control samples. The graphene oxide treatments led to lower Superoxide Dismutase (SOD), Peroxidase (POD), Catalase (CAT) activity and Malondialdehyde (MDA) content in the WT and transgenic plants. 20 mg/L graphene oxide treatment also affected the transcript levels of IAA7, IAA4 and IAA10 but the effect on the wild type and corresponding transgenic plants was different. IAA4 transcription level decreased both in the WT and Prd29A::LeNCED1 transgenic plants while the IAA7 transcription level decreased in the transgenic plants and increased in the WT tomato. The IAA10 transcription level decreased in the WT tomato and increased in the Prd29A::LeNCED1 transgenic plants. Graphene oxide treatments resulted in higher transcription level of ABCG25 and ABCG40 in the WT plants but had no significant effect on transgenic plants. The transcription level of NCED in the WT and Prd29A::LeNCED1 transgenic plants treated with graphene oxide increased significantly, however, it was higher in the transgenic plants than in the WT tomato after 15 d treatment, indicating that the graphene oxide activated the rd29A promoter as does drought and salt. The HD-ZIP transcription level only decreased significantly in the treated Prd29A::LeNCED1 transgenic plants. All these results suggested that there was a crosstalk between ABA and graphene oxide and the graphene oxide affected plant growth through the ABA and IAA pathway.

Network-wise cerebral blood flow redistribution after 20 Hz rTMS on left dorso-lateral prefrontal cortex.

PubMed

Shang, Yuan-Qi; Xie, Jun; Peng, Wei; Zhang, Jian; Chang, Da; Wang, Ze

2018-04-01

The repetitive application of transcranial magnetic stimulation (rTMS) on left dorsolateral prefrontal cortex (DLPFC) has been consistently shown to be beneficial for treating various neuropsychiatric or neuropsychological disorders, but its neural mechanisms still remain unclear. The purpose of this study was to measure the effects of high-frequency left DLPFC rTMS using cerebral blood flow (CBF) collected from 40 young healthy subjects before and after applying 20 Hz left DLPFC rTMS or SHAM stimulations. Relative CBF (rCBF) changes before and after 20 Hz rTMS or SHAM were assessed with paired-t test. The results show that 20 Hz DLPFC rTMS induced CBF redistribution in the default mode network, including increased rCBF in left medial temporal cortex (MTC)/hippocampus, but reduced rCBF in precuneus and cerebellum. Meanwhile, SHAM stimulation didn't produce any rCBF changes. After controlling SHAM effects, only the rCBF increase in MTC/hippocampus remained. Those data suggest that the beneficial effects of high-frequency rTMS may be through a within-network rCBF redistribution. Copyright © 2018 Elsevier B.V. All rights reserved.

Temperature dependent of IVR investigated by steady-state and time-frequency resolved CARS for liquid nitrobenzene and nitromethane

NASA Astrophysics Data System (ADS)

Yang, Yanqiang; Zhu, Gangbei; Yan, Lin; Liu, Xiaosong; Yang's Ultrafast Spectroscopy Group Team

2017-06-01

Intramolecular vibrational energy redistribution (IVR) is important process in thermal decomposition, shock chemistry and photochemistry. Anti-Stokes Raman scattering is sensitive to the vibrational population in excited states because only vibrational excited states are responsible to the anti-Stokes Raman scattering, does not vibrational ground states. In this report, steady-state anti-Stokes Raman spectroscopy and broad band ultrafast coherent anti-Stokes Raman scattering (CARS) are performed. The steady-state anti-Stokes Raman spectroscopy shows temperature dependent of vibrational energy redistribution in vibrational excited-state molecule, and reveal that, in liquid nitrobenzene, with temperature increasing, vibrational energy is mainly redistributed in NO2 symmetric stretching mode, and phenyl ring stretching mode of νCC. For liquid nitromethane, it is found that, with temperature increasing, vibrational energy concentrate in CN stretching mode and methyl umbrella vibrational mode. In the broad band ultrafast CARS experiment, multiple vibrational modes are coherently excited to vibrational excited states, and the time-frequency resolved CARS spectra show the coincident IVR processes. This work is supported by the National Natural Science Foundation of China (Grant Numbers 21673211 and 11372053), and the Science Challenging Program (Grant Number JCKY2016212A501).

Monitoring an air pollution episode in Shenzhen by combining MODIS satellite images and the HYSPLIT model

NASA Astrophysics Data System (ADS)

Li, Lili; Liu, Yihong; Wang, Yunpeng

2017-07-01

Urban air pollution is influenced not only by local emission sources including industry and vehicles, but also greatly by regional atmospheric pollutant transportation from the surrounding areas, especially in developed city clusters, like the Pearl River Delta (PRD). Taking an air pollution episode in Shenzhen as an example, this paper investigates the occurrence and evolution of the pollution episode and identifies the transport pathways of air pollutants in Shenzhen by combining MODIS satellite images and HYSPLIT back trajectory analysis. Results show that this pollution episode is mainly caused by the local emission of pollutants in PRD and oceanic air masses under specific weather conditions.

NASA 2010 Pharmacology Evidence Review

NASA Technical Reports Server (NTRS)

Steinberg, Susan

2011-01-01

In 2008, the Institute of Medicine reviewed NASA's Human Research Program Evidence in assessing the Pharmacology risk identified in NASA's Human Research Program Requirements Document (PRD). Since this review there was a major reorganization of the Pharmacology discipline within the HRP, as well as a re-evaluation of the Pharmacology evidence. This panel is being asked to review the latest version of the Pharmacology Evidence Report. Specifically, this panel will: (1) Appraise the descriptions of the human health-related risk in the HRP PRD. (2) Assess the relevance and comprehensiveness of the evidence in identifying potential threats to long-term space missions. (3) Assess the associated gaps in knowledge and identify additional areas for research as necessary.

Increased human occupation and agricultural development accelerates the population contraction of an estuarine delphinid.

PubMed

Lin, Wenzhi; Karczmarski, Leszek; Xia, Jia; Zhang, Xiyang; Yu, Xinjian; Wu, Yuping

2016-10-19

Over the past few thousand years, human development and population expansion in southern China have led to local extirpation and population contraction of many terrestrial animals. At what extent this early human-induced environmental change has also affected coastal marine species remains poorly known. We investigated the demographic history of the Indo-Pacific humpback dolphin (Sousa chinensis) in the Pearl River Delta (PRD); an obligatory inshore species known for its susceptibility to anthropogenic impacts in one of China's most developed coastal regions. Although the deltaic evolution of PRD has been influenced by climate since the Holocene, ~74% reduction of the dolphin's effective population size occurred within the last 2000 years, consistent with ~61% habitat contraction during this period. This considerable and recent population contraction may have been due to land use practices and deforestation in the upper/middle Pearl River region, all leading to increasing sedimentation rate in the estuarine area. As anthropogenic impacts within the drainage of Pearl River affected a vast area, coastal dolphins and large terrestrial mammals in southern China may share a similar demographic history, whilst the demographic and biogeographic history of the PRD humpback dolphins may be symptomatic of similar processes that this species may have undergone elsewhere in the region.

The cytochrome complex SoxXA of Paracoccus pantotrophus is produced in Escherichia coli and functional in the reconstituted sulfur-oxidizing enzyme system.

PubMed

Rother, Dagmar; Friedrich, Cornelius G

2002-07-29

The heterodimeric c-type cytochrome complex SoxXA of Paracoccus pantotrophus was produced in Escherichia coli. The soxX and soxA genes, separated by two genes in the sox gene cluster of P. pantotrophus, were fused with ribosome binding sites optimal for E. coli and combined to give soxXA in pRD133.27. The cytochrome complex SoxXA was produced in E. coli M15 containing pRD133.27, pREP4 encoding the Lac repressor and plasmid pEC86, carrying essential cytochrome c maturation genes. SoxX and SoxA were formed in a ratio of about 2.5:1. SoxA appeared to be unstable when not complexed with SoxX. The cytochrome complex SoxXA, purified to homogeneity from periplasmic extracts of E. coli M15 (pRD133.27, pREP4, pEC86), exhibited identical biochemical and biophysical properties as compared to SoxXA of P. pantotrophus. Moreover, this cytochrome complex was shown to be equally catalytically active with respect to rates and reactivity with different sulfur substrates in the reconstituted sulfur-oxidizing enzyme system using homogeneous Sox-proteins of P. pantotrophus. Homogeneous SoxX was catalytically inactive.

The effect of operant-conditioning balance training on the down-regulation of spinal H-reflexes in a spastic patient.

PubMed

Hoseini, Najmeh; Koceja, David M; Riley, Zachary A

2011-10-24

Spasticity in chronic hemiparetic stroke patients has primarily been treated pharmacologically. However, there is increasing evidence that physical rehabilitation can help manage hyper-excitability of reflexes (hyperreflexia), which is a primary contributor to spasticity. In the present study, one chronic hemiparetic stroke patient operantly conditioned the soleus H-reflex while training on a balance board for two weeks. The results showed a minimal decrease in the Hmax-Mmax ratio for both the affected and unaffected limb, indicating that the H-reflex was not significantly altered with training. Alternatively, paired-reflex depression (PRD), a measure of history-dependent changes in reflex excitability, could be conditioned. This was evident by the rightward shift and decreased slope of reflex excitability in the affected limb. The non-affected limb decreased as well, although the non-affected limb was very sensitive to PRD initially, whereas the affected limb was not. Based on these results, it was concluded that PRD is a better index of hyperreflexia, and this measurement could be more informative of synapse function than simple H-reflexes. This study presents a novel and non-pharmacological means of managing spasticity that warrants further investigation with the potential of being translated to the clinic. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Assessing the effects of urbanization on the environment with soil legacy and current-use insecticides: a case study in the Pearl River Delta, China.

PubMed

Wei, Yan-Li; Bao, Lian-Jun; Wu, Chen-Chou; He, Zai-Cheng; Zeng, Eddy Y

2015-05-01

To evaluate the impacts of anthropogenic events on the rapid urbanized environment, the levels of legacy organochlorine pesticides (OCPs) and current-use insecticides (CUPs), i.e., dichlorodiphenyltrichloroethane and its metabolites (DDTs), hexachlorocyclohexanes (HCHs), pyrethroids and organophosphates in soil of the Pearl River Delta (PRD) and surrounding areas were examined. Spatial concentration distributions of legacy OCPs and CUPs shared similar patterns, with higher concentrations occurred in the central PRD with more urbanization level than that in the PRD's surrounding areas. Furthermore, relatively higher concentrations of OCPs and CUPs were found in the residency land than in other land-use types, which may be attributed to land-use change under rapid urbanization. Moderate correlations between gross domestic production or population density and insecticide levels in fifteen administrative districts indicated that insecticide spatial distributions may be driven by economic prosperity. The soil-air diffusive exchanges of DDTs and HCHs demonstrated that soil was a sink of atmospheric o,p'-DDE, o,p'-DDD, p,p'-DDD and o,p'-DDT, and was a secondary source of HCHs and p,p'-DDT to atmosphere. The soil inventories of DDTs and HCHs (100 ± 134 and 83 ± 70 tons) were expected to decrease to half of their current values after 18 and 13 years, respectively, whereas the amounts of pyrethroids and organophosphates (39 and 6.2 tons) in soil were estimated to decrease after 4 and 2 years and then increase to 87 and 1.0 tons after 100 years. In this scenario, local residents in the PRD and surrounding areas will expose to the high health risk for pyrethroids by 2109. Strict ban on the use of technical DDTs and HCHs and proper training of famers to use insecticides may be the most effective ways to alleviate the health effect of soil contamination. Copyright © 2015 Elsevier B.V. All rights reserved.

Effect of elastic strain redistribution on electronic band structures of compressively strained GaInAsP/InP membrane quantum wires

NASA Astrophysics Data System (ADS)

Ferdous, F.; Haque, A.

2007-05-01

The effect of redistribution of elastic strain relaxation on the energy band structures of GaInAsP/InP compressively strained membrane quantum wires fabricated by electron-beam lithography, reactive-ion etching and two-step epitaxial growth is theoretically studied using an 8-band k ṡp method. Anisotropic strain analysis by the finite element method shows that due to etching away the top and the bottom InP clad layers in membrane structures, redistribution of strain occurs. It is found that strain redistribution increases the effective bandgap of membrane quantum wire structures causing a blueshift of the emission frequency. Comparison with effective bandgap calculations neglecting confinement and band mixing demonstrates that neglect of these effects leads to an overestimation of the change in the bandgap. We have also investigated the effect of variation of wire width, barrier strain compensation, number of stacked quantum wire layers, and thickness of the top and the bottom residual InP layers in membrane structures on the change in the effective bandgap of membrane structures.

Studies of water storage and other contributions to changes in the rotation of the Earth

NASA Technical Reports Server (NTRS)

Wilson, Clark R.

1991-01-01

The effects were determined of the global redistribution of water mass on various geodetic observables, especially polar motion, and complementary observables such as geodetic satellite positions. The effect of water mass redistribution has been and continues to be less well known and more difficult to observe than effects of air mass distribution, yet the water contribution is potentially significant over a large range of periods. The current understanding is reviewed of the contribution of polar drift, decadal polar motion, Chandler and annual wobbles, and higher frequency polar motion, as determined through the efforts of the funded work within the NASA Crustal Dynamics Project, and in the context of the general literature on the subject. Water mass redistribution is either demonstrably important to the excitation of each of these, or is probably important given a lack of other likely excitation sources.

The contributions of biomass burning to primary and secondary organics: A case study in Pearl River Delta (PRD), China.

PubMed

Wang, BaoLin; Liu, Ying; Shao, Min; Lu, SiHua; Wang, Ming; Yuan, Bin; Gong, ZhaoHeng; He, LingYan; Zeng, LiMin; Hu, Min; Zhang, YuanHang

2016-11-01

Synchronized online measurements of gas- and particle- phase organics including non-methane hydrocarbons (NMHCs), oxygenated volatile organic compounds (OVOCs) and submicron organic matters (OM) were conducted in November 2010 at Heshan, Guangdong provincial supersite, China. Several biomass burning events were identified by using acetonitrile as a tracer, and enhancement ratios (EnRs) of organics to carbon monoxide (CO) obtained from this work generally agree with those from rice straw burning in previous studies. The influences of biomass burning on NMHCs, OVOCs and OM were explored by comparing biomass burning impacted plumes (BB plumes) and non-biomass burning plumes (non-BB plumes). A photochemical age-based parameterization method was used to characterize primary emission and chemical behavior of those three organic groups. The emission ratios (EmRs) of NMHCs, OVOCs and OM to CO increased by 27-71%, 34-55% and 67% in BB plumes, respectively, in comparison with non-BB plumes. The estimated formation rate of secondary organic aerosol (SOA) in BB plumes was found to be 24% faster than non-BB plumes. By applying the above emission ratios to the whole PRD, the annual emissions of VOCs and OM from open burning of crop residues would be 56.4 and 3.8Gg in 2010 in PRD, respectively. Copyright © 2016 Elsevier B.V. All rights reserved.

[Numerical modeling analysis of secondary organic aerosol (SOA) combined with the ground-based measurements in the Pearl River Delta region].

PubMed

Guo, Xiao-Shuang; Situ, Shu-Ping; Wang, Xue-Mei; Ding, Xiang; Wang, Xin-Ming; Yan, Cai-Qing; Li, Xiao-Ying; Zheng, Mei

2014-05-01

Two simulations were conducted with different secondary organic aerosol (SOA) methods-VBS (volatile basis set) approach and SORGAM (secondary organic aerosol model) , which have been coupled in the WRF/Chem (weather research and forecasting model with chemistry) model. Ground-based observation data from 18th to 25th November 2008 were used to examine the model performance of SOA in the Pearl River Delta(PRD)region. The results showed that VBS approach could better reproduce the temporal variation and magnitude of SOA compared with SORGAM, and the mean absolute deviation and correlation coefficient between the observed and the simulated data using VBS approach were -4.88 microg m-3 and 0.91, respectively, while they were -5.32 microg.m-3 and 0. 18 with SORGAM. This is mainly because the VBS approach considers SOA precursors with a wider volatility range and the process of chemical aging in SOA formation. Spatiotemporal distribution of SOA in the PRD from the VBS simulation was also analyzed. The results indicated that the SOA has a significant diurnal variation, and the maximal SOA concentration occurred at noon and in the early afternoon. Because of the transport and the considerable spatial distribution of O3 , the SOA concentrations were different in different PRD cities, and the highest concentration of SOA was observed in the downwind area, including Zhongshan, Zhuhai and Jiangmen.

Spatial and temporal trends of short- and medium-chain chlorinated paraffins in sediments off the urbanized coastal zones in China and Japan: A comparison study.

PubMed

Zeng, Lixi; Lam, James C W; Horii, Yuichi; Li, Xiaolin; Chen, Weifang; Qiu, Jian-Wen; Leung, Kenneth M Y; Yamazaki, Eriko; Yamashita, Nobuyoshi; Lam, Paul K S

2017-05-01

To examine the impacts of urbanization and industrialization on the coastal environment, and assess the effectiveness of control measures on the contamination by chlorinated paraffins (CPs) in East Asia, surface and core sediments were sampled from the urbanized coastal zones in China and Japan (i.e., Pearl River Delta (PRD), Hong Kong waters and Tokyo Bay) and analyzed for short-chain (SCCPs) and medium-chain CPs (MCCPs). Much higher concentrations of CPs were found in the industrialized PRD than in adjacent Hong Kong waters. Significant correlation between CP concentration and population density in the coastal district of Hong Kong was observed (r 2  = 0.72 for SCCPs and 0.55 for MCCPs, p < 0.05), highlighting the effect of urbanization. By contrast, a relatively lower pollution level of CPs was detected in Tokyo Bay. More long-chain groups within SCCPs in the PRD than in Hong Kong waters and Tokyo Bay implied the effect of industrialization. Comparison of temporal trends between Hong Kong outer harbor with Tokyo Bay shows the striking difference in historical deposition of CPs under different regulatory situations in China and Japan. For the first time, the declining CP concentrations in Tokyo Bay, Japan, attest to the effectiveness of emissions controls. Copyright © 2017 Elsevier Ltd. All rights reserved.

Quantifying black carbon light absorption enhancement with a novel statistical approach

NASA Astrophysics Data System (ADS)

Wu, Cheng; Wu, Dui; Zhen Yu, Jian

2018-01-01

Black carbon (BC) particles in the atmosphere can absorb more light when coated by non-absorbing or weakly absorbing materials during atmospheric aging, due to the lensing effect. In this study, the light absorption enhancement factor, Eabs, was quantified using a 1-year measurement of mass absorption efficiency (MAE) in the Pearl River Delta region (PRD). A new approach for calculating primary MAE (MAEp), the key for Eabs estimation, is demonstrated using the minimum R squared (MRS) method, exploring the inherent source independency between BC and its coating materials. A unique feature of Eabs estimation with the MRS approach is its insensitivity to systematic biases in elemental carbon (EC) and σabs measurements. The annual average Eabs550 is found to be 1.50 ± 0.48 (±1 SD) in the PRD region, exhibiting a clear seasonal pattern with higher values in summer and lower in winter. Elevated Eabs in the summertime is likely associated with aged air masses, predominantly of marine origin, along with long-range transport of biomass-burning-influenced air masses from Southeast Asia. Core-shell Mie simulations along with measured Eabs and absorption Ångström exponent (AAE) constraints suggest that in the PRD, the coating materials are unlikely to be dominated by brown carbon and the coating thickness is higher in the rainy season than in the dry season.

A novel ECG data compression method based on adaptive Fourier decomposition

NASA Astrophysics Data System (ADS)

Tan, Chunyu; Zhang, Liming

2017-12-01

This paper presents a novel electrocardiogram (ECG) compression method based on adaptive Fourier decomposition (AFD). AFD is a newly developed signal decomposition approach, which can decompose a signal with fast convergence, and hence reconstruct ECG signals with high fidelity. Unlike most of the high performance algorithms, our method does not make use of any preprocessing operation before compression. Huffman coding is employed for further compression. Validated with 48 ECG recordings of MIT-BIH arrhythmia database, the proposed method achieves the compression ratio (CR) of 35.53 and the percentage root mean square difference (PRD) of 1.47% on average with N = 8 decomposition times and a robust PRD-CR relationship. The results demonstrate that the proposed method has a good performance compared with the state-of-the-art ECG compressors.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Casini, R.; Manso Sainz, R.

We present the frequency redistribution function for a polarized three-term atom of the Λ-type in the collisionless regime, and we specialize it to the case where both the initial and final terms of the three-state transition are metastable (i.e., with infinitely sharp levels). This redistribution function represents a generalization of the well-known R {sub II} function to the case where the lower terms of the transition can be polarized and carry atomic coherence, and it can be applied to the investigation of polarized line formation in tenuous plasmas, where collisional rates may be low enough that anisotropy-induced atomic polarization survivesmore » even in the case of metastable levels.« less

Broad-Band Analysis of Polar Motion Excitations

NASA Astrophysics Data System (ADS)

Chen, J.

2016-12-01

Earth rotational changes, i.e. polar motion and length-of-day (LOD), are driven by two types of geophysical excitations: 1) mass redistribution within the Earth system, and 2) angular momentum exchange between the solid Earth (more precisely the crust) and other components of the Earth system. Accurate quantification of Earth rotational excitations has been difficult, due to the lack of global-scale observations of mass redistribution and angular momentum exchange. The over 14-years time-variable gravity measurements from the Gravity Recovery and Climate Experiment (GRACE) have provided a unique means for quantifying Earth rotational excitations from mass redistribution in different components of the climate system. Comparisons between observed Earth rotational changes and geophysical excitations estimated from GRACE, satellite laser ranging (SLR) and climate models show that GRACE-derived excitations agree remarkably well with polar motion observations over a broad-band of frequencies. GRACE estimates also suggest that accelerated polar region ice melting in recent years and corresponding sea level rise have played an important role in driving long-term polar motion as well. With several estimates of polar motion excitations, it is possible to estimate broad-band noise variance and noise power spectra in each, given reasonable assumptions about noise independence. Results based on GRACE CSR RL05 solutions clearly outperform other estimates with the lowest noise levels over a broad band of frequencies.

Study of the effect of sawteeth on fast ions and neutron emission in MAST using a neutron camera

NASA Astrophysics Data System (ADS)

Cecconello, M.; Sperduti, A.; the MAST team

2018-05-01

The effect of the sawtooth instability on the confinement of fast ions on MAST, and the impact it has on the neutron emission, has been studied in detail using the TRANSP/NUBEAM codes coupled to a full orbit following code. The sawtooth models in TRANSP/NUBEAM indicate that, on MAST, passing and trapped fast ions are redistributed in approximately equal number and on a level that is consistent with the observations. It has not been possible to discriminate between the different sawtooth models since their predictions are all compatible with the neutron camera observations. Full orbit calculations of the fast ion motion have been used to estimate the characteristic time scales and energy thresholds that according to theoretical predictions govern the fast ions redistribution: no energy threshold for the redistribution for either passing and trapped fast ions was found. The characteristic times have, however, frequencies that are comparable with the frequencies of a m = 1, n = 1 perturbation and its harmonics with toroidal mode numbers n=2, \\ldots , 4, suggesting that on spherical tokamaks, in addition to the classical sawtooth-induced transport mechanisms of fast ions by attachment to the evolving perturbation and the associated E × B drift, a resonance mechanism between the m = 1 perturbation and the fast ions orbits might be at play.

How Wolf-Rayet winds are driven by starlight and spectral lines

NASA Astrophysics Data System (ADS)

Onifer, Andrew Joseph, III

Finding the cause of the enormous increase in the mass- loss rate of a Wolf-Rayet (W-R) star, as compared to its O star progenitor, has remained a challenge for many years. This thesis explores the hypothesis that line driving causes the large observed W-R mass-loss rates. Frequency redistribution can cause the photons to filter into gaps in the line spectrum, reducing the efficiency of line driving. Therefore, the role that frequency redistribution plays in lowering the predicted mass-loss rate is explored, both via simple two-domain idealizations of the line list and via a real W-R line list. A simple analytic theory, called the Statistical Sobolev Rosseland (SSR) theory, is developed that calculates the local efficiency of line driving in a completely redistributing wind. In the process a conceptual language is developed to explain the key issues in W-R wind line driving. The results are that with no redistribution, the reduction in radius, and corresponding increase in temperature, of an O star as it evolves into a W-R star causes roughly a six-fold increase in the mass-loss rate. However, with large amounts of redistribution, the efficiency of the wind drops greatly in the presence of spectral gaps. In the most extreme case of SSR, the mass- loss rate drops by a factor of up to an order of magnitude relative to the gray value. To avoid this it is necessary to fill the gaps in the spectrum, and the effect that ionization stratification has in filling the gaps globally over the wind is explored. It is found that with the current line list ionization changes can only fill the gaps sufficiently to cause about a factor of two increase over the SSR value. The conclusion is that in order for line driving to explain the mass-loss rates of W-R winds, more opacity needs to be discovered to fill the gaps, either locally, or globally over a realistic range of ionization strata.

Contacts in the Office of Pesticide Programs, Pesticide Re-Evaluation Division

EPA Pesticide Factsheets

Contact the Pesticide Re-Evaluation Division (PRD) about registration review and reregistration follow up (including post-RED activities, product reregistration, and implementing certain tolerance reassessment decisions) for conventional pesticides.

A Novel ECG Data Compression Method Using Adaptive Fourier Decomposition With Security Guarantee in e-Health Applications.

PubMed

Ma, JiaLi; Zhang, TanTan; Dong, MingChui

2015-05-01

This paper presents a novel electrocardiogram (ECG) compression method for e-health applications by adapting an adaptive Fourier decomposition (AFD) algorithm hybridized with a symbol substitution (SS) technique. The compression consists of two stages: first stage AFD executes efficient lossy compression with high fidelity; second stage SS performs lossless compression enhancement and built-in data encryption, which is pivotal for e-health. Validated with 48 ECG records from MIT-BIH arrhythmia benchmark database, the proposed method achieves averaged compression ratio (CR) of 17.6-44.5 and percentage root mean square difference (PRD) of 0.8-2.0% with a highly linear and robust PRD-CR relationship, pushing forward the compression performance to an unexploited region. As such, this paper provides an attractive candidate of ECG compression method for pervasive e-health applications.

Membrane-containing virus particles exhibit the mechanics of a composite material for genome protection.

PubMed

Azinas, S; Bano, F; Torca, I; Bamford, D H; Schwartz, G A; Esnaola, J; Oksanen, H M; Richter, R P; Abrescia, N G

2018-04-26

The protection of the viral genome during extracellular transport is an absolute requirement for virus survival and replication. In addition to the almost universal proteinaceous capsids, certain viruses add a membrane layer that encloses their double-stranded (ds) DNA genome within the protein shell. Using the membrane-containing enterobacterial virus PRD1 as a prototype, and a combination of nanoindentation assays by atomic force microscopy and finite element modelling, we show that PRD1 provides a greater stability against mechanical stress than that achieved by the majority of dsDNA icosahedral viruses that lack a membrane. We propose that the combination of a stiff and brittle proteinaceous shell coupled with a soft and compliant membrane vesicle yields a tough composite nanomaterial well-suited to protect the viral DNA during extracellular transport.

VOCs and OVOCs distribution and control policy implications in Pearl River Delta region, China

NASA Astrophysics Data System (ADS)

Louie, Peter K. K.; Ho, Josephine W. K.; Tsang, Roy C. W.; Blake, Donald R.; Lau, Alexis K. H.; Yu, Jian Zhen; Yuan, Zibing; Wang, Xinming; Shao, Min; Zhong, Liuju

2013-09-01

Ambient air measurements of volatile organic compounds (VOCs) and oxygenated volatile organic compounds (OVOCs) were conducted and characterised during a two-year grid study in the Pearl River Delta (PRD) region of southern China. The present grid study pioneered the systematic investigation of the nature and characteristics of complex VOC and OVOC sources at a regional scale. The largest contributing VOCs, accounting over 80% of the total VOCs mixing ratio, were toluene, ethane, ethyne, propane, ethene, butane, benzene, pentane, ethylbenzene, and xylenes. Sub-regional VOC spatial characteristics were identified, namely: i) relatively fresh pollutants, consistent with elevated vehicular and industrial activities, around the PRD estuary; and ii) a concentration gradient with higher mixing ratios of VOCs in the west as compared with the eastern part of PRD. Based on alkyl nitrate aging determination, a high hydroxyl radical (OH) concentration favoured fast hydrocarbon reactions and formation of locally produced ozone. The photochemical reactivity analysis showed aromatic hydrocarbons and alkenes together consisted of around 80% of the ozone formation potential (OFP) among the key VOCs. We also found that the OFP from OVOCs should not be neglected since their OFP contribution was more than one-third of that from VOCs alone. These findings support the choice of current air pollution control policy which focuses on vehicular sources but warrants further controls. Industrial emissions and VOCs emitted by solvents should be the next targets for ground-level ozone abatement.

Assessment of transboundary environmental effects in the Pearl River Delta Region: Is there a role for strategic environmental assessment?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marsden, Simon, E-mail: simon.marsden@flinders.edu.au

2011-11-15

China's EIA Law does not require transboundary proposals to be assessed, despite recognition of this globally, for example in the Espoo Convention and Kiev Protocol, and in the European EIA and SEA Directives. In a transboundary context assessment within a state is unusual, as regulating these effects is primarily about the relationship between states. However where a state has more than one legal system such as in the Pearl River Delta (PRD) Region of southern China, transboundary effects should also be addressed. Yet despite the geographical connections between Guangdong Province in mainland China (where the EIA Law applies) and themore » Hong Kong and Macau Special Administrative Regions (which have their own provisions, neither of which requires transboundary assessments), EIA and SEA are carried out separately. Coordinated or joint approaches to transboundary assessment are generally absent, with the legal autonomy of Hong Kong and Macau a major constraint. As a result institutional responses at the policy level have developed. The article considers global experiences with regulating transboundary EIA and SEA, and analyses potential application to land use, transport and air and water planning in the PRD Region. If applied, benefits may include prevention or mitigation of cumulative effects, broader public participation, and improvements to environmental governance. The PRD Region experience may encourage China to conduct and coordinate EIA and SEA processes with neighbouring states, which has been non-existent or extremely limited to date.« less

Development and Validation of Eco-Friendly Liquid Chromatographic and Spectrophotometric Methods for Simultaneous Determination of Coformulated Drugs: Phenylephrine Hydrochloride and Prednisolone Acetate.

PubMed

Mostafa, Nadia M; Elsayed, Ghada M; Hassan, Nagiba Y; El Mously, Dina A

2017-11-01

Five simple, sensitive, and eco-friendly LC and UV spectrophotometric methods have been developed for the simultaneous determination of phenylephrine hydrochloride (PHE) and prednisolone acetate (PRD) in their combined dosage form. The first method was reversed-phase (RP) LC using methanol-water-heptane-1-sulfonic acid sodium salt (75 + 25 + 0.1, v/v/w) as a mobile phase. Separation was achieved using an XSelect HSS reversed-phase C18 analytical column (250 × 4.6 mm, 5µm). The flow rate was 1.0 mL/min and UV detection was done at 230 nm. Quantification was achieved over the concentration ranges of 5-50 µg/mL for PHE and 2-90 µg/mL for PRD. Four spectrophotometric methods were proposed, namely dual wavelength, first derivative of ratio spectra, ratio difference, and mean-centering of ratio spectra. Linearity was observed in the concentration ranges of 10-120 and 5-35 µg/mL for PHE and PRD, respectively, for the spectrophotometric methods. Green solvents were used in the proposed methods because they play a vital role in the analytical methods' influence on the environment. The suggested methods were validated regarding linearity, accuracy, and precision according to the International Conference on Harmonization guidelines, with satisfactory results. These methods could be used as harmless substitutes for routine analysis of the mentioned drugs, with no interference from excipients.

Semantic modeling of plastic deformation of polycrystalline rock

NASA Astrophysics Data System (ADS)

Babaie, Hassan A.; Davarpanah, Armita

2018-02-01

We have developed the first iteration of the Plastic Rock Deformation (PRD) ontology by modeling the semantics of a selected set of deformational processes and mechanisms that produce, reconfigure, displace, and/or consume the material components of inhomogeneous polycrystalline rocks. The PRD knowledge model also classifies and formalizes the properties (relations) that hold between instances of the dynamic physical and chemical processes and the rock components, the complex physio-chemical, mathematical, and informational concepts of the plastic rock deformation system, the measured or calculated laboratory testing conditions, experimental procedures and protocols, the state and system variables, and the empirical flow laws that define the inter-relationships among the variables. The ontology reuses classes and properties from several existing ontologies that are built for physics, chemistry, biology, and mathematics. With its flexible design, the PRD ontology is well positioned to incrementally develop into a model that more fully represents the knowledge of plastic deformation of polycrystalline rocks in the future. The domain ontology will be used to consistently annotate varied data and information related to the microstructures and the physical and chemical processes that produce them at different spatial and temporal scales in the laboratory and in the solid Earth. The PRDKB knowledge base, when built based on the ontology, will help the community of experimental structural geologists and metamorphic petrologists to coherently and uniformly distribute, discover, access, share, and use their data through automated reasoning and integration and query of heterogeneous experimental deformation data that originate from autonomous rock testing laboratories.

B chromosomes are associated with redistribution of genetic recombination towards lower recombination chromosomal regions in perennial ryegrass.

PubMed

Harper, John; Phillips, Dylan; Thomas, Ann; Gasior, Dagmara; Evans, Caron; Powell, Wayne; King, Julie; King, Ian; Jenkins, Glyn; Armstead, Ian

2018-04-09

Supernumerary 'B' chromosomes are non-essential components of the genome present in a range of plant and animal species-including many grasses. Within diploid and polyploid ryegrass and fescue species, including the forage grass perennial ryegrass (Lolium perenne L.), the presence of B chromosomes has been reported as influencing both chromosome pairing and chiasma frequencies. In this study, the effects of the presence/absence of B chromosomes on genetic recombination has been investigated through generating DArT (Diversity Arrays Technology) marker genetic maps for six perennial ryegrass diploid populations, the pollen parents of which contained either two B or zero B chromosomes. Through genetic and cytological analyses of these progeny and their parents, we have identified that, while overall cytological estimates of chiasma frequencies were significantly lower in pollen mother cells with two B chromosomes as compared with zero B chromosomes, the recombination frequencies within some marker intervals were actually increased, particularly for marker intervals in lower recombination regions of chromosomes, namely pericentromeric regions. Thus, in perennial ryegrass, the presence of two B chromosomes redistributed patterns of meiotic recombination in pollen mother cells in ways which could increase the range of allelic variation available to plant breeders.

Sound Power Minimization of Circular Plates Through Damping Layer Placement

NASA Astrophysics Data System (ADS)

Wodtke, H.-W.; Lamancusa, J. S.

1998-09-01

Damping layers, widely used for noise and vibration control of thin-walled structures, can be designed to provide an optimal trade-off between performance and weight which is of particular importance in the automotive and aircraft industry. The goal of the presented work is the minimization of sound power radiated from plates under broadband excitation by redistribution of unconstrained damping layers. The total radiated sound power is assumed to be represented by the sound power radiated at the structural resonances. Resonance tracking is performed by means of single-degree-of-freedom (SDOF)-approximations based on near-resonance responses and their frequency derivatives. Axisymmetric vibrations of circular plates under several boundary and forcing conditions are considered. Frequency dependent Young's modulus and loss factor of the damping material are taken into account. Vibration analysis is based on the finite element method (FEM) while acoustic radiation is treated by means of Rayleigh's integral formula. It is shown that, starting from a uniform damping layer distribution, substantial reduction in radiated sound power can be achieved through redistribution of the damping layers. Depending on the given situation, these reductions are not only due to amplitude reductions but also to changes in vibration shapes and frequencies.

Femtosecond solvation and the bandshape of polar dyes

NASA Astrophysics Data System (ADS)

Ernsting, N. P.; Eilers-König, N.; Kemeter, K.; Kovalenko, S.; Ruthmann, J.

1996-04-01

The bandwidth of gain spectra for the dye DASPI in polar solvents and its evolution is described by Brownian oscillators with different frequencies for the ground- and excited electronic states. Comparison with experiments reveals a fast relaxation process which is assigned to vibrational redistribution.

The psychological disengagement model among women in science, engineering, and technology.

PubMed

Beaton, Ann M; Tougas, Francine; Rinfret, Natalie; Monger, Tanya

2015-09-01

Psychological responses to personal relative deprivation based on self/outgroup comparisons (named self/outgroup PRD) were explored among women in science, engineering, and technology according to the Psychological Disengagement Model. Three studies revealed that the experience of self/outgroup PRD increased women's likelihood of discounting the feedback they received at work. In turn, discounting led them to devalue their profession. Each study further documented the damaging effect of both psychological disengagement mechanisms. Study 1 (N = 93) revealed that discounting and devaluing were associated with decreased self-esteem. These results were replicated in Studies 2 and 3. Study 2 (N = 163) demonstrated that discounting and devaluing were also associated with reduced self-esteem stability. Study 3 (N = 187) further showed that psychological disengagement was also associated with women's occupational commitment. Theoretical and practical implications of these results are considered. © 2014 The British Psychological Society.

Compression of electromyographic signals using image compression techniques.

PubMed

Costa, Marcus Vinícius Chaffim; Berger, Pedro de Azevedo; da Rocha, Adson Ferreira; de Carvalho, João Luiz Azevedo; Nascimento, Francisco Assis de Oliveira

2008-01-01

Despite the growing interest in the transmission and storage of electromyographic signals for long periods of time, few studies have addressed the compression of such signals. In this article we present an algorithm for compression of electromyographic signals based on the JPEG2000 coding system. Although the JPEG2000 codec was originally designed for compression of still images, we show that it can also be used to compress EMG signals for both isotonic and isometric contractions. For EMG signals acquired during isometric contractions, the proposed algorithm provided compression factors ranging from 75 to 90%, with an average PRD ranging from 3.75% to 13.7%. For isotonic EMG signals, the algorithm provided compression factors ranging from 75 to 90%, with an average PRD ranging from 3.4% to 7%. The compression results using the JPEG2000 algorithm were compared to those using other algorithms based on the wavelet transform.

Proline-Dependent Regulation of Clostridium difficile Stickland Metabolism

PubMed Central

Bouillaut, Laurent; Self, William T.

2013-01-01

Clostridium difficile, a proteolytic Gram-positive anaerobe, has emerged as a significant nosocomial pathogen. Stickland fermentation reactions are thought to be important for growth of C. difficile and appear to influence toxin production. In Stickland reactions, pairs of amino acids donate and accept electrons, generating ATP and reducing power in the process. Reduction of the electron acceptors proline and glycine requires the d-proline reductase (PR) and the glycine reductase (GR) enzyme complexes, respectively. Addition of proline in the medium increases the level of PR protein but decreases the level of GR. We report the identification of PrdR, a protein that activates transcription of the PR-encoding genes in the presence of proline and negatively regulates the GR-encoding genes. The results suggest that PrdR is a central metabolism regulator that controls preferential utilization of proline and glycine to produce energy via the Stickland reactions. PMID:23222730

Heavy metal pollution in surface soils of Pearl River Delta, China.

PubMed

Jinmei, Bai; Xueping, Liu

2014-12-01

Heavy metal pollution is an increasing environmental problem in Chinese regions undergoing rapid economic and industrial development, such as the Pearl River Delta (PRD), southern China. We determined heavy metal concentrations in surface soils from the PRD. The soils were polluted with heavy metals, as defined by the Chinese soil quality standard grade II criteria. The degree of pollution decreased in the order Cd > Cu > Ni > Zn > As > Cr > Hg > Pb. The degree of heavy metal pollution by land use decreased in the order waste treatment plants (WP) > urban land (UL) > manufacturing industries (MI) > agricultural land (AL) > woodland (WL) > water sources (WS). Pollution with some of the metals, including Cd, Cu, Ni, and Zn, was attributed to the recent rapid development of the electronics and electroplating industries. Cd, Hg, and Pb (especially Cd) pose high potential ecological risks in all of the zones studied. The soils posing significantly high and high potential ecological risks from Cd covered 73.3 % of UL, 50 % of MI and WP land, and 48.5 % of AL. The potential ecological risks from heavy metals by land use decreased in the order UL > MI > AL > WP > WL > WS. The control of Cd, Hg, and Pb should be prioritized in the PRD, and emissions in wastewater, residue, and gas discharges from the electronics and electroplating industry should be decreased urgently. The use of chemical fertilizers and pesticides should also be decreased.

Biomonitoring PFAAs in blood and semen samples: Investigation of a potential link between PFAAs exposure and semen mobility in China.

PubMed

Song, Xiaofei; Tang, Shaoyu; Zhu, Haimin; Chen, Zhiyuan; Zang, Zhijun; Zhang, Yanan; Niu, Xiaojun; Wang, Xiaojun; Yin, Hua; Zeng, Feng; He, Chang

2018-04-01

Perfluoroalkyl acids (PFAAs) have been suspected to act as endocrine disruptors and adversely affect human reproductive health. We aimed to investigate the association between PFAAs in blood and semen, explore a potential link between PFAAs exposure and semen quality in the population of the Pearl River Delta (PRD) region in China, one of the "world factories". The monitoring results demonstrated that the population (103 male participants) from the PRD region in this study had higher PFAAs levels in blood and semen than some other areas in China. PFOS was found at the highest mean concentrations of 118.16 ng/mL in blood and 5.31 ng/mL in semen among the nine PFAAs. Significant associations were found between concentrations of several analytes in blood and semen, including Σ 9 PFAAs (r = 0.475, P < .01), PFOA (r = 0.215, P = .029), PFHS (r = 0.458, P < .01) and PFOS (r = 0.981, P < .01). BMI was the most important factor to PFAAs, but there was no significant difference in PFAAs concentrations in blood and semen collected from participants with different smoking and drinking habits, education background and occupations. Negative correlations were significantly observed between sperm motility and PFBA, PFPeA, PFHxA, PFBS, PFOA, PFHS, PFOS and Σ 9 PFAAs in semen. Therefore, exposure to PFAAs may result in a decline in semen mobility in participants from the PRD region. Copyright © 2018 Elsevier Ltd. All rights reserved.

[Temporal and spatial characteristics of atmospheric NO2 over Hainan Island and the pollutant sources in recent 10 years].

PubMed

Fu, Chuan-bo; Chen, You-long; Dan, Li; Tang, Jia-xiang

2015-01-01

The temporal-spatial characteristics of the tropospheric column NO2 (TroNO2) and total column NO2 (TotNO2) over Hainan Island are analyzed using remote sensing data derived from OMI sensor, and also combining surface wind, SO2, HYSPLIT model to research the source of atmospheric pollutants over Hainan Island. The results show that: The value of NO2 in northern area is higher than that in southern area, and the value of NO, in central mountainous area is lower than those other places. In addition, the seasonal variation of NO2 indicates that NO2 is higher in winter and lower in summer, which can be attributed to precipitation in summer and external transport of atmospheric pollutants in winter. Long-term changes of NO2 in Hainan Island appear opposite trends during winter and summer, which is declining in winter and has a weak increase in summer. The reasonable explanation is that local emissions of pollutants play an important role in summer, but external transport is the main resource of pollutants over Hainan Island. The TroNO2 in Haikou City has a good relationship with favorable delivered days in PRD, the correlation coefficient is 0.84 with 99% confidence level. Moreover, there are 3 transport paths in Dec. 2013 which can impact Haikou City from backward trajectory analysis, but all of them pass through the PRD, which can further prove that atmospheric pollutants of Hainan Island in winter are mainly delivery from PRD region.

The Source, Spatial Distribution and Risk Assessment of Heavy Metals in Soil from the Pearl River Delta Based on the National Multi-Purpose Regional Geochemical Survey.

PubMed

Zhang, Lingyan; Guo, Shuhai; Wu, Bo

2015-01-01

The data on the heavy metal content at different soil depths derived from a multi-purpose regional geochemical survey in the Pearl River Delta (PRD) were analyzed using ArcGIS 10.0. By comparing their spatial distributions and areas, the sources of heavy metals (Cd, Hg, As and Pb) were quantitatively identified and explored. Netted measuring points at 25 ×25 km were set over the entire PRD according to the geochemical maps. Based on the calculation data obtained from different soil depths, the concentrations of As and Cd in a large area of the PRD exceeded the National Second-class Standard. The spatial disparity of the geometric centers in the surface soil and deep soil showed that As in the surface soil mainly came from parent materials, while Cd had high consistency in different soil profiles because of deposition in the soil forming process. The migration of Cd also resulted in a considerable ecological risk to the Beijiang and Xijiang River watershed. The potential ecological risk index followed the order Cd ≥ Hg > Pb > As. According to the sources, the distribution trends and the characteristics of heavy metals in the soil from the perspective of the whole area, the Cd pollution should be repaired, especially in the upper reaches of the Xijiang and Beijiang watershed to prevent risk explosion while the pollution of Hg and Pb should be controlled in areas with intense human activity, and supervision during production should be strengthened to maintain the ecological balance of As.

The Source, Spatial Distribution and Risk Assessment of Heavy Metals in Soil from the Pearl River Delta Based on the National Multi-Purpose Regional Geochemical Survey

PubMed Central

Zhang, Lingyan; Guo, Shuhai; Wu, Bo

2015-01-01

The data on the heavy metal content at different soil depths derived from a multi-purpose regional geochemical survey in the Pearl River Delta (PRD) were analyzed using ArcGIS 10.0. By comparing their spatial distributions and areas, the sources of heavy metals (Cd, Hg, As and Pb) were quantitatively identified and explored. Netted measuring points at 25 ×25 km were set over the entire PRD according to the geochemical maps. Based on the calculation data obtained from different soil depths, the concentrations of As and Cd in a large area of the PRD exceeded the National Second-class Standard. The spatial disparity of the geometric centers in the surface soil and deep soil showed that As in the surface soil mainly came from parent materials, while Cd had high consistency in different soil profiles because of deposition in the soil forming process. The migration of Cd also resulted in a considerable ecological risk to the Beijiang and Xijiang River watershed. The potential ecological risk index followed the order Cd ≥ Hg > Pb > As. According to the sources, the distribution trends and the characteristics of heavy metals in the soil from the perspective of the whole area, the Cd pollution should be repaired, especially in the upper reaches of the Xijiang and Beijiang watershed to prevent risk explosion while the pollution of Hg and Pb should be controlled in areas with intense human activity, and supervision during production should be strengthened to maintain the ecological balance of As. PMID:26230506

High-temperature metamorphism and its relation with magmatism (Svecofennian Belt, the Ladoga region, Russia)

NASA Astrophysics Data System (ADS)

Baltybaev, Shauket

2010-05-01

The Ladoga region, situated in the south-eastern part of the Fennoscandian shield, is subdivided into the Archean (ARD) and the Proterozoic (PRD) domains. The boundary between them is a wide shear-zone. The ARD consists mostly of AR-PR middle-low temperature gneisses and the PRD consists of turbidites, pelites, volcanics metamorphosed under HT-conditions (granulite facies). Metamorphism within the PRD is culminated at T= 800-900C and P=5-6 kbar. The peak of metamorphism of granulite facies is dated at 1881 Ma by Pb-Pb stepwise leaching method of rock-forming minerals of the granulites. Pb-Pb results are within error limits coeval with the U-Pb ages of metamorphic monazites. The same (1881Ma) age has gabbro-enderbites. Next stage of metamorphism lasts from 1881 to 1860 Ma under conditions of amphibolite facies. It was restricted with U-Pb, Pb-Pb, Sm-Nd data based on the closure temperature of zircon, monazite, garnet, sillimanite from gneisses, leucosomes of migmatites and synmetamorphic diorites and tonalites. The lowermost point of the trend shows P-T: ~3-4 kbar, 600C. By the time 1860 Ma K-rich granites were emplaced and the uppermost limit for granulite metamorphism comes from the ages of the aplitic/pegmatitic veins (1860-1850 Ma), which cut the K-rich granites. Thermal and tectonic settings can be described based on spatial and temporal changes during magma emplacement. The granulites of the PRD were produced by the emplacement of the extensive basic intrusion (gabbro-enderbites) into the lower-middle crust. A prolonged thermal flux over all area was supported by new generated dioritic and tonalitic melts, which were intruded into the middle crust. The final stage of tectono-metamorphic evolution was marked by emplacement of the K-rich granites. Numerical simulation of the process of magma emplacement (sequences: gabbro-enderbites, diorites and tonalites) and related heat production shows good correlation between intrusive activity and metamorphism of the surrounding rocks. Baltybaev Sh. K., Levchenkov O. A., Levsky L. K., Eklund O., Kilpeläinen T. 2006. Two metamorphic stages in the Svecofennian Domain: evidence from the isotopic geochronological study of the Ladoga and Sulkava metamorphic complexes. Petrology, 14(3), 247-261.

Comparative gene expression supports the origin of the incisor and molar process from a single endite in the mandible of the red flour beetle Tribolium castaneum

PubMed Central

2013-01-01

Background The biting edge of the primitive arthropod mandible consists of a biting incisor process and a crushing molar process. These structures are thought to be derived from a structure known as an endite but the precise details of this are not understood. Various hypotheses concerning the number of endites present in the arthropod mandible have been proposed. In the developing embryo, the mandible has an inner and outer lobe that are likely to develop into the incisor and molar processes of the larval mandible; these two lobes are commonly held to be derived from separate endites and to be serially homologous to the galea and lacinia endites of the maxillary appendage respectively (Machida). Results We undertook a study of the development of the embryonic mandible of the beetle Tribolium castaneum using the expression of developmental genes as markers of the developing endites in the mandible and maxilla. The Tribolium ortholog of paired (Tc-prd) has expression domains in the developing maxillary and labial endites as well as the inner and outer lobes of the mandible. Following the expression of Tc-prd in the developing mandible through to late stage embryos shows that the molar and incisor process develop from the inner and outer lobes respectively. In addition to Tc-prd, we compared the expression of genes in the endites of the maxilla to the mandible to draw conclusions about the number of endites in the mandible. Homologs of dachshund are typically expressed in the endites of mandibulate gnathal appendages. Comparison of the expression of Tc-prd, Tribolium dachshund (Tc-dac) and Tribolium wingless (Tc-wg) between the endites of the maxilla and the mandible suggest that, while there are two endites in the maxilla only a single endite is present in the mandible. Conclusions Comparative gene expression suggests that the Tribolium mandible has a single endite from which both mandible lobes are derived. Our results do not support Machida’s hypothesis homologising the incisor and molar processes of the mandible to the galea and lacinia endites of the maxilla. We propose, instead, that both incisor and molar processes are derived from a single endite serially homologous to the lacinia of the maxilla. PMID:23280103

Bacterial Investigation of Ammonium-rich Sediment in the Pearl River Delta, China

NASA Astrophysics Data System (ADS)

Liu, K.; Chunbo, H.; Jiao, J. J.; Jidong, G.

2011-12-01

High ammonium loading of groundwater is a major concern because of the potential toxicity to ecosystem and human health. As one of the most complex large-scale delta systems in China, Pearl River Delta (PRD) was reported to have the highest ammonium concentration for natural groundwater ever reported globally. In this research, borehole SD14 was drilled through the aquitard into the basal aquifer in the PRD. 16S rRNA gene library construction and Denaturing Gradient Gel Electrophoresis (DGGE) analysis were conducted to reveal bacterial community variation of different geology strata. A total of 161 clones from three 16S rRNA libraries were sequenced and clustered into 55 distinct operational taxonomic units (OTU) at 3% cutoff. The phylogenetic analysis indicated that the predominant bacterial phylum was Proteobacteria (50.9%), followed by Chloroflexi (16.8%), Acidobacteria (4.38%) and Firmicutes (3.73%). In the sediment samples from SD14 at the depths of 6.9m, 22.5m and 37.4m, Proteobacteria made up 60.3%, 42.0% and 35.3% of the communities respectively, showing a declining ratio with the depth. Most of the bacteria in all the samples were previously discovered in marine environments, indicating that SD14 used to be in a marine sedimentary environment. Bacteria associated with iron oxidation and nitrogen fixing were found in the sample at 6.9 m, while in the other two samples there existed bacteria which were associated with methane cycling, sulfate reducing and denitrifying. The DGGE results showed that microbial community structures varied significantly with the increase of depth, and that Delftia acidovorans, a species of Proteobacteria which was able to reduce nitrate to nitrite, was the predominant species in samples at 22.5 and 37.4 m, suggesting ammonium as a control factor shaping the bacterial community. The results of this research provided important information of the bacteria in the PRD sediments. High bacterial diversity was observed in samples, and similar bacteria presenting in comparable habits were found. Mutual effects between bacteria and environment widely exist through PRD aquifer-aquitard system, and abnormal high ammonium was probably released during organic nitrogen dissimilation coupled with sulfate reduction.
Chemical Parameters of SD14

Materials investigation of thermal triggers used in pressure relief devices on transit buses.

DOT National Transportation Integrated Search

2003-07-01

This investigation pertains to the composition and general condition of the thermally activated trigger mechanism of Pressure Relief Devices [PRD's], safety devices used on compressed natural gas cylinders commonly used to store fuel on transit buses...

Measurements and modelling of fast-ion redistribution due to resonant MHD instabilities in MAST

NASA Astrophysics Data System (ADS)

Jones, O. M.; Cecconello, M.; McClements, K. G.; Klimek, I.; Akers, R. J.; Boeglin, W. U.; Keeling, D. L.; Meakins, A. J.; Perez, R. V.; Sharapov, S. E.; Turnyanskiy, M.; the MAST Team

2015-12-01

The results of a comprehensive investigation into the effects of toroidicity-induced Alfvén eigenmodes (TAE) and energetic particle modes on the NBI-generated fast-ion population in MAST plasmas are reported. Fast-ion redistribution due to frequency-chirping TAE in the range 50 kHz-100 kHz and frequency-chirping energetic particle modes known as fishbones in the range 20 kHz-50 kHz, is observed. TAE and fishbones are also observed to cause losses of fast ions from the plasma. The spatial and temporal evolution of the fast-ion distribution is determined using a fission chamber, a radially-scanning collimated neutron flux monitor, a fast-ion deuterium alpha spectrometer and a charged fusion product detector. Modelling using the global transport analysis code Transp, with ad hoc anomalous diffusion and fishbone loss models introduced, reproduces the coarsest features of the affected fast-ion distribution in the presence of energetic particle-driven modes. The spectrally and spatially resolved measurements show, however, that these models do not fully capture the effects of chirping modes on the fast-ion distribution.

Excited stilbene: intramolecular vibrational redistribution and solvation studied by femtosecond stimulated Raman spectroscopy.

PubMed

Weigel, A; Ernsting, N P

2010-06-17

Excited-state relaxation of cis- and trans-stilbene is traced with femtosecond stimulated Raman spectroscopy, exploiting S(n) <-- S(1) resonance conditions. For both isomers, decay in Raman intensity, shift of spectral positions, and broadening of the bands indicate intramolecular vibrational redistribution (IVR). In n-hexane this process effectively takes 0.5-0.7 ps. Analysis of the intensity decay allows us to further distinguish two phases for trans-stilbene: fast IVR within a subset of modes (approximately 0.3 ps) followed by slower equilibration over the full vibrational manifold (approximately 0.9 ps). In acetonitrile IVR completes with 0.15 ps; this acceleration may originate from symmetry breakage induced by the polar solvent. Another process, dynamic solvation by acetonitrile, is seen as spectral narrowing and characteristic band shifts of the C=C stretch and phenyl bending modes with 0.69 ps. Wavepacket motion is observed in both isomers as oscillation of low-frequency bands with their pertinent mode frequency (90 or 195 cm(-1) in trans-stilbene; 250 cm(-1) in cis-stilbene). Anharmonic coupling shows up as a modulation of high-frequency peak positions by phenyl/ethylene torsion modes of 57 and 90 cm(-1). Decay and shift of the 90 cm(-1) inverse Raman band within the first 0.3 ps suggests a gradual involvement of phenyl/ethylene torsion in relaxation. In cis- and trans-stilbene, low-frequency spectral changes are found within 0.15 ps, indicating an additional ultrafast process.

High Frequency Chandler Wobble Excitation

NASA Astrophysics Data System (ADS)

Seitz, F.; Stuck, J.; Thomas, M.

2003-04-01

Variations of Earth rotation on sub-daily to secular timescales are caused by mass redistributions in the Earth system as a consequence of geophysical processes and gravitational influences. Forced oscillations of polar motion are superposed by free oscillations of the Earth, i.e. the Chandler wobble and the free core nutation. In order to study the interactions between externally induced polar motion and the Earth's free oscillations, a non-linear gyroscopic model has been developed. In most of the former investigations on polar motion, the Chandler wobble is introduced as a damped oscillation with predetermined frequency and amplitude. However, as the effect of rotational deformation is a backcoupling mechanism of polar motion on the Earth's rotational dynamics, both period and amplitude of the Chandler wobble are time-dependent when regarding additional excitations from, e.g., atmospheric or oceanic mass redistributions. The gyroscopic model is free of any explicit information concerning amplitude, phase, and period of free oscillations. The characteristics of the Earth's free oscillation is reproduced by the model from rheological and geometrical parameters and rotational deformation is taken into account. This enables to study the time variable Chandler oscillation when the gyro is forced with atmospheric and oceanic angular momentum from the global atmospheric ECHAM3-T21 general circulation model together with the ocean model for circulation and tides OMCT driven by ECHAM including surface pressure. Besides, mass redistributions in the Earth's body due to gravitational and loading deformations are regarded and external torques exerted by Moon and Sun are considered. The numerical results of the gyro are significantly related with the geodetically observed time series of polar motion published by the IERS. It is shown that the consistent excitation is capable to counteract the damping and thus to maintain the Chandler amplitude. Spectral analyses of the ECHAM and OMCT forcing fields give no hint for increased excitation power in the Chandler band. Thus it is assumed, that continuous high frequency excitation due to stochastic weather phenomena is responsible for the perpetuation of the Chandler wobble.

Ultrasonic Doppler measurement of renal artery blood flow

NASA Technical Reports Server (NTRS)

Freund, W. R.; Beaver, W. L.; Meindl, J. D.

1976-01-01

Studies were made of (1) blood flow redistribution during lower body negative pressure (LBNP), (2) the profile of blood flow across the mitral annulus of the heart (both perpendicular and parallel to the commissures), (3) testing and evaluation of a number of pulsed Doppler systems, (4) acute calibration of perivascular Doppler transducers, (5) redesign of the mitral flow transducers to improve reliability and ease of construction, and (6) a frequency offset generator designed for use in distinguishing forward and reverse components of blood flow by producing frequencies above and below the offset frequency. Finally methodology was developed and initial results were obtained from a computer analysis of time-varying Doppler spectra.

Partial root-zone drying and conventional deficit irrigation applied during the whole berry growth maintain yield and berry quality in 'Crimson Seedless' table grapes

NASA Astrophysics Data System (ADS)

Pérez-Pastor, Alejandro; Domingo, Rafael; De la Rosa, Jose M.°; Rosario Conesa Saura, M.°

2016-04-01

To compare the effects of partial root-zone drying and conventional deficit irrigation applied during post-veraison and the whole berry growth on water relations, yield and berry quality, one experiment was conducted in a commercial vineyard of 'Crimson Seedless' table grapes. Five irrigation treatments were imposed: (i) Control (CTL) irrigated to 110% of crop evapotranspiration (ETc), (ii) regulated deficit irrigation (RDI) irrigated at 50% of CTL during the non- critical period of post-verasion, (iii) continuous deficit irrigation (DIc), irrigated at 50% of CTL throughout the whole berry growing season, (iv) partial root-zone drying (PRD), irrigated similar to RDI, but alternating the irrigation applied in the dry side every 10-14 days; and (v) continuous partial root-zone drying (PRDc), irrigated as DIc but alternating the irrigation in the dry side every 10-14 days. RDI and PRD received 24% and 28% less water than CTL, respectively. These reductions were higher in DIc and PRDc (65% and 53%, respectively). Total yield was not affected by any DI strategy. Only significantly lower values were observed in the weight and height's berries in respect to CTL. However, the colour parameters evaluated increased in all DI treatments, being slightly higher in DIc and PRDc compared with RDI and PRD. In addition, total soluble solids (TSS) were significantly higher in DIc, compared to other irrigated counterparts. Our findings showed that the application of water deficit during the whole berry growth through the use of DIc and PRDc, can be considered for irrigation scheduling in 'Crimson Seedless' table grapes. Acknowledgements This work has been funded by the European Union LIFE+ project IRRIMAN (LIFE13 ENV/ES/000539).

An AIS-based high-resolution ship emission inventory and its uncertainty in Pearl River Delta region, China.

PubMed

Li, Cheng; Yuan, Zibing; Ou, Jiamin; Fan, Xiaoli; Ye, Siqi; Xiao, Teng; Shi, Yuqi; Huang, Zhijiong; Ng, Simon K W; Zhong, Zhuangmin; Zheng, Junyu

2016-12-15

Ship emissions contribute significantly to air pollution and impose health risks to residents along the coastal area. By using the refined data from the Automatic Identification System (AIS), this study developed a highly resolved ship emission inventory for the Pearl River Delta (PRD) region, China, home to three of ten busiest ports in the world. The region-wide SO 2 , NO X , CO, PM 10 , PM 2.5 , and VOC emissions in 2013 were estimated to be 61,484, 103,717, 10,599, 7155, 6605, and 4195t, respectively. Ocean going vessels were the largest contributors of the total emissions, followed by coastal vessels and river vessels. In terms of ship type, container ship was the leading contributor, followed by conventional cargo ship, dry bulk carrier, fishing ship, and oil tanker. These five ship types accounted for >90% of total emissions. The spatial distributions of emissions revealed that the key emission hot spots all concentrated within the newly proposed emission control area (ECA) and ship emissions within ECA covered >80% of total ship emissions in the PRD, highlighting the importance of ECA in emissions reduction in the PRD. The uncertainties of emission estimates of pollutants were quantified, with lower bounds of -24.5% to -21.2% and upper bounds of 28.6% to 33.3% at 95% confidence intervals. The lower uncertainties in this study highlighted the powerfulness of AIS data in improving ship emission estimates. The AIS-based bottom-up methodology can be used for developing and upgrading ship emission inventory and formulating effective control measures on ship emissions in other port regions wherever possible. Copyright © 2016 Elsevier B.V. All rights reserved.

Particulate matter pollution in the megacities of the Pearl River Delta, China - a systematic literature review and health risk assessment.

PubMed

Jahn, Heiko J; Schneider, Alexandra; Breitner, Susanne; Eissner, Romy; Wendisch, Manfred; Krämer, Alexander

2011-07-01

The exposure to ambient particulate matter (PM) pollution is a major threat to public health. Chinese megacities are coined by high levels of PM. Our aims were to examine the concentration levels of PM in megacities (Guangzhou, Hong Kong, and Shenzhen) of the Pearl River Delta (PRD), South China; to compare the results with international and national air quality guidelines; and to assess the health impact in terms of possible reductions in premature deaths due to PM reduction. The Medline(®) data base was used to identify published studies (systematic literature search). Based on our appraisal criteria 13 studies remained in the analysis. Additionally, publicly available data were extracted from data sources provided by municipal authorities of the cities under study. PM data reported in μg/m(3) were abstracted from single studies and municipal reports. If possible, the PM data were stratified for season of data collection (summer/winter half-year) and simple means were calculated for cities, seasons and months. Based on the abstracted data, a health impact assessment (HIA) was done in order to estimate potential preventable premature deaths due to PM pollution in the cities. Almost all PM data exceeded national and international air quality guidelines. Our HIA showed that in Guangzhou ten thousands of premature deaths could be prevented if the PM burden was reduced to these air quality limit values. We identified no suitable epidemiological study reporting PM according to our study protocol. Further epidemiological studies should be carried out to more precisely determine the spatial distribution of PM-related health risks in PRD. Environmental protection measures and public health interventions are required to reduce burden of PM-related diseases in PRD. Copyright © 2011 Elsevier GmbH. All rights reserved.

Evolution of homeobox genes.

PubMed

Holland, Peter W H

2013-01-01

Many homeobox genes encode transcription factors with regulatory roles in animal and plant development. Homeobox genes are found in almost all eukaryotes, and have diversified into 11 gene classes and over 100 gene families in animal evolution, and 10 to 14 gene classes in plants. The largest group in animals is the ANTP class which includes the well-known Hox genes, plus other genes implicated in development including ParaHox (Cdx, Xlox, Gsx), Evx, Dlx, En, NK4, NK3, Msx, and Nanog. Genomic data suggest that the ANTP class diversified by extensive tandem duplication to generate a large array of genes, including an NK gene cluster and a hypothetical ProtoHox gene cluster that duplicated to generate Hox and ParaHox genes. Expression and functional data suggest that NK, Hox, and ParaHox gene clusters acquired distinct roles in patterning the mesoderm, nervous system, and gut. The PRD class is also diverse and includes Pax2/5/8, Pax3/7, Pax4/6, Gsc, Hesx, Otx, Otp, and Pitx genes. PRD genes are not generally arranged in ancient genomic clusters, although the Dux, Obox, and Rhox gene clusters arose in mammalian evolution as did several non-clustered PRD genes. Tandem duplication and genome duplication expanded the number of homeobox genes, possibly contributing to the evolution of developmental complexity, but homeobox gene loss must not be ignored. Evolutionary changes to homeobox gene expression have also been documented, including Hox gene expression patterns shifting in concert with segmental diversification in vertebrates and crustaceans, and deletion of a Pitx1 gene enhancer in pelvic-reduced sticklebacks. WIREs Dev Biol 2013, 2:31-45. doi: 10.1002/wdev.78 For further resources related to this article, please visit the WIREs website. The author declares that he has no conflicts of interest. Copyright © 2012 Wiley Periodicals, Inc.

EVALUATING THE SENSITIVITY OF RADIONUCLIDE DETECTORS FOR CONDUCTING A MARITIME ON-BOARD SEARCH USING MONTE CARLO SIMULATION IMPLEMENTED IN AVERT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harris, S; Dave Dunn, D

The sensitivity of two specific types of radionuclide detectors for conducting an on-board search in the maritime environment was evaluated using Monte Carlo simulation implemented in AVERT{reg_sign}. AVERT{reg_sign}, short for the Automated Vulnerability Evaluation for Risk of Terrorism, is personal computer based vulnerability assessment software developed by the ARES Corporation. The sensitivity of two specific types of radionuclide detectors for conducting an on-board search in the maritime environment was evaluated using Monte Carlo simulation. The detectors, a RadPack and also a Personal Radiation Detector (PRD), were chosen from the class of Human Portable Radiation Detection Systems (HPRDS). Human Portable Radiationmore » Detection Systems (HPRDS) serve multiple purposes. In the maritime environment, there is a need to detect, localize, characterize, and identify radiological/nuclear (RN) material or weapons. The RadPack is a commercially available broad-area search device used for gamma and also for neutron detection. The PRD is chiefly used as a personal radiation protection device. It is also used to detect contraband radionuclides and to localize radionuclide sources. Neither device has the capacity to characterize or identify radionuclides. The principal aim of this study was to investigate the sensitivity of both the RadPack and the PRD while being used under controlled conditions in a simulated maritime environment for detecting hidden RN contraband. The detection distance varies by the source strength and the shielding present. The characterization parameters of the source are not indicated in this report so the results summarized are relative. The Monte Carlo simulation results indicate the probability of detection of the RN source at certain distances from the detector which is a function of transverse speed and instrument sensitivity for the specified RN source.« less

Estimated Acute Effects of Ambient Ozone and Nitrogen Dioxide on Mortality in the Pearl River Delta of Southern China

PubMed Central

Tao, Yebin; Zhong, Liuju; Lu, Shou-En; Li, Yi; Dai, Lingzhen; Zhang, Yuanhang; Zhu, Tong

2011-01-01

Background and objectives: Epidemiologic studies have attributed adverse health effects to air pollution; however, controversy remains regarding the relationship between ambient oxidants [ozone (O3) and nitrogen dioxide (NO2)] and mortality, especially in Asia. We conducted a four-city time-series study to investigate acute effects of O3 and NO2 in the Pearl River Delta (PRD) of southern China, using data from 2006 through 2008. Methods: We used generalized linear models with Poisson regression incorporating natural spline functions to analyze acute mortality in association with O3 and NO2, with PM10 (particulate matter ≤ 10 μm in diameter) included as a major confounder. Effect estimates were determined for individual cities and for the four cities as a whole. We stratified the analysis according to high- and low- exposure periods for O3. Results: We found consistent positive associations between ambient oxidants and daily mortality across the PRD cities. Overall, 10-μg/m3 increases in average O3 and NO2 concentrations over the previous 2 days were associated with 0.81% [95% confidence interval (CI): 0.63%, 1.00%] and 1.95% (95% CI: 1.62%, 2.29%) increases in total mortality, respectively, with stronger estimated effects for cardiovascular and respiratory mortality. After adjusting for PM10, estimated effects of O3 on total and cardiovascular mortality were stronger for exposure during high-exposure months (September through November), whereas respiratory mortality was associated with O3 exposure during nonpeak exposure months only. Conclusions: Our findings suggest significant acute mortality effects of O3 and NO2 in the PRD and strengthen the rationale for further limiting the ambient pollution levels in the area. PMID:22157208

Panama: Political and Economic Conditions and U.S. Relations

DTIC Science & Technology

2007-09-04

Legislative Assembly elected Pedro Miguel Gonzalez of the ruling Democratic Revolutionary Party (PRD) as head of the legislature. The State...elections for candidate Carlos Duque , who the Noriega regime had tried to impose on the electorate through fraud.) Instead, Pérez Balladares focused

Virus fate and transport during artificial recharge with recycled water

USGS Publications Warehouse

Anders, Robert; Chrysikopoulos, C.V.

2005-01-01

A field‐scale experiment was conducted at a research site using bacterial viruses (bacteriophage) MS2 and PRD1 as surrogates for human viruses, bromide as a conservative tracer, and tertiary‐treated municipal wastewater (recycled water) to investigate the fate and transport of viruses during artificial recharge. Observed virus concentrations were fitted using a mathematical model that simulates virus transport in one‐dimensional, homogeneous, water‐saturated porous media accounting for virus sorption (or filtration), virus inactivation, and time‐dependent source concentration. The fitted time‐dependent clogging rate constants were used to estimate the collision efficiencies for bacteriophage MS2 and PRD1 during vertical fully saturated flow. Furthermore, the corresponding time‐dependent collision efficiencies for both bacteriophage asymptotically reached similar values at the various sampling locations. These results can be used to develop an optimal management scenario to maximize the amount of recycled water that can be applied to the spreading grounds while still maintaining favorable attachment conditions for virus removal.

Source apportionment of atmospheric mercury pollution in China using the GEOS-Chem model.

PubMed

Wang, Long; Wang, Shuxiao; Zhang, Lei; Wang, Yuxuan; Zhang, Yanxu; Nielsen, Chris; McElroy, Michael B; Hao, Jiming

2014-07-01

China is the largest atmospheric mercury (Hg) emitter in the world. Its Hg emissions and environmental impacts need to be evaluated. In this study, China's Hg emission inventory is updated to 2007 and applied in the GEOS-Chem model to simulate the Hg concentrations and depositions in China. Results indicate that simulations agree well with observed background Hg concentrations. The anthropogenic sources contributed 35-50% of THg concentration and 50-70% of total deposition in polluted regions. Sensitivity analysis was performed to assess the impacts of mercury emissions from power plants, non-ferrous metal smelters and cement plants. It is found that power plants are the most important emission sources in the North China, the Yangtze River Delta (YRD) and the Pearl River Delta (PRD) while the contribution of non-ferrous metal smelters is most significant in the Southwest China. The impacts of cement plants are significant in the YRD, PRD and Central China. Copyright © 2014 Elsevier Ltd. All rights reserved.

Antibiotics in riverine runoff of the Pearl River Delta and Pearl River Estuary, China: concentrations, mass loading and ecological risks.

PubMed

Xu, Weihai; Yan, Wen; Li, Xiangdong; Zou, Yongde; Chen, Xiaoxiang; Huang, Weixia; Miao, Li; Zhang, Ruijie; Zhang, Gan; Zou, Shichun

2013-11-01

Ten antibiotics belonging to three groups (macrolides, fluoroquinolones and sulfonamides) were investigated in riverine runoff of the Pearl River Delta (PRD) and Pearl River Estuary (PRE), South China for assessing the importance of riverine runoff in the transportation of contaminants from terrestrial sources to the open ocean. All antibiotics were detected in the eight outlets with concentrations ranging from 0.7 to 127 ng L(-1). The annual mass loadings of antibiotics from the PRD to the PRE and coast were 193 tons with 102 tons from the fluoroquinolone group. It showed that antibiotics decreased from the riverine outlets to the PRE and open ocean. Risk assessment showed that most of these antibiotics showed various ecological risks to the relevant aquatic organisms, in which ofloxacin (OFL), erythromycin (ETM) and ciprofloxacin (CIP) posed high ecological risks to the studied aquatic environments. Copyright © 2013 Elsevier Ltd. All rights reserved.

Retrieval and Validation of Aerosol Optical Depth by using the GF-1 Remote Sensing Data

NASA Astrophysics Data System (ADS)

Zhang, L.; Xu, S.; Wang, L.; Cai, K.; Ge, Q.

2017-05-01

Based on the characteristics of GF-1 remote sensing data, the method and data processing procedure to retrieve the Aerosol Optical Depth (AOD) are developed in this study. The surface contribution over dense vegetation and urban bright target areas are respectively removed by using the dark target and deep blue algorithms. Our method is applied for the three serious polluted Beijing-Tianjin-Hebei (BTH), Yangtze River Delta (YRD) and Pearl River Delta (PRD) regions. The retrieved AOD are validated by ground-based AERONET data from Beijing, Hangzhou, Hong Kong sites. Our results show that, 1) the heavy aerosol loadings are usually distributed in high industrial emission and dense populated cities, with the AOD value near 1. 2) There is a good agreement between satellite-retrievals and in-site observations, with the coefficient factors of 0.71 (BTH), 0.55 (YRD) and 0.54(PRD). 3) The GF-1 retrieval uncertainties are mainly from the impact of cloud contamination, high surface reflectance and assumed aerosol model.

Distribution, sources, and fluxes of heavy metals in the Pearl River Delta, South China.

PubMed

Geng, Junjie; Wang, Yiping; Luo, Hanjin

2015-12-30

Riverine samples were collected at various locations in the Pearl River Delta (PRD) to determine the concentrations of heavy metals (Cr, Ni, Cu, Mn, Zn, Cd, and Pb) in time and space and to estimate the fluxes of heavy metals to the coastal waters off South China. Most of the elements exhibit clear temporal and spatial trends. Principal component analysis shows that surface erosion is the major factor affecting metal concentrations in particulates in the PRD. Natural geology is an important source of these heavy metals. The annual fluxes of Cr, Ni, Cu, Mn, Zn, Cd, and Pb in upstream and downstream were 445, 256, 241, 3293, 1279, 12, and 317 t/year and 1823, 1144, 1786, 15,634, 6183, 74, and 2017 t/year, respectively. A comparison indicated that the annual fluxes of Mn accounted for 1.3% of the global river fluxes, whereas other elements contribute <1%. Copyright © 2015 Elsevier Ltd. All rights reserved.

New primary renal diagnosis codes for the ERA-EDTA

PubMed Central

Venkat-Raman, Gopalakrishnan; Tomson, Charles R.V.; Gao, Yongsheng; Cornet, Ronald; Stengel, Benedicte; Gronhagen-Riska, Carola; Reid, Chris; Jacquelinet, Christian; Schaeffner, Elke; Boeschoten, Els; Casino, Francesco; Collart, Frederic; De Meester, Johan; Zurriaga, Oscar; Kramar, Reinhard; Jager, Kitty J.; Simpson, Keith

2012-01-01

The European Renal Association-European Dialysis and Transplant Association (ERA-EDTA) Registry has produced a new set of primary renal diagnosis (PRD) codes that are intended for use by affiliated registries. It is designed specifically for use in renal centres and registries but is aligned with international coding standards supported by the WHO (International Classification of Diseases) and the International Health Terminology Standards Development Organization (SNOMED Clinical Terms). It is available as supplementary material to this paper and free on the internet for non-commercial, clinical, quality improvement and research use, and by agreement with the ERA-EDTA Registry for use by commercial organizations. Conversion between the old and the new PRD codes is possible. The new codes are very flexible and will be actively managed to keep them up-to-date and to ensure that renal medicine can remain at the forefront of the electronic revolution in medicine, epidemiology research and the use of decision support systems to improve the care of patients. PMID:23175621

Towards the effect of acoustic emission (AE) sensor positioning within AE signal parameters in sliding on bulk ultrafine-grained materials

NASA Astrophysics Data System (ADS)

Filippov, A. V.; Tarasov, S. Yu.; Podgornykh, O. A.; Chazov, P. A.; Shamarin, N. N.; Filippova, E. O.

2017-12-01

The effect of AE sensor positioning on the bulk ultrafine-grained materials used for sliding against steel ball has been investigated. Two versions of AE sensor positioning have been tested and showed the different attenuation levels. The experimentally obtained AE signal waveforms have been analyzed under the AE signal parameters such as a median frequency and AE energy. It was established that the AE sensor positioned on the sample supporting plate in the vicinity of the sample tested allowed redistribution of the signal energy from a low-frequency to high-frequency range as well as extending the median frequency range as compared to those obtained by mounting the sensor on the immobile sample holder.

West Europe Report

DTIC Science & Technology

1985-07-15

Lisbon TAL & QUAL in Portuguese 17 May 85 p 3 [Text] Manuel da Costa Bras, Lt Col in the reserves and High Commissioner against Corruption, is facing...people around Gen Eanes, starting with Lt Col Melo Antunes. The PRD itself has already announced many times that it would not oppose such an

Panama: Political and Economic Conditions and U.S. Relations

DTIC Science & Technology

2009-03-26

On July 11, 2007, Panama’s unicameral legislature overwhelmingly approved...majority of seats in the unicameral National Assembly. Before the U.S...Although Moscoso took the presidency, the PRD-led New Nation coalition won a majority of 41 seats in the 71-member unicameral Legislative Assembly

Chemical and stable carbon isotopic composition of PM2.5 from on-road vehicle emissions in the PRD region and implication for vehicle emission control policy

NASA Astrophysics Data System (ADS)

Dai, S.; Bi, X.; Chan, L. Y.; He, J.; Wang, B.; Wang, X.; Sheng, G.; Fu, J.

2014-11-01

Vehicle emission is a major source of urban air pollution. In recent decade, the Chinese government has introduced a range of policies to reduce the vehicle emission. In order to understand the chemical characteristics of PM2.5 from on-road vehicle emission in the Pearl River Delta (PRD) region and to evaluate the effectiveness of control policies on vehicles emission, the emission factors of PM2.5 mass, elemental carbon (EC), organic carbon (OC), water-soluble organic carbon (WSOC), water-soluble inorganic ions (WSII), metal elements, organic compounds and stable carbon isotopic composition were measured in the Zhujiang Tunnel of Guangzhou, the PRD region of China in 2013. Emission factors of PM2.5 mass, OC, EC, and WSOC were 92.4, 16.7, 16.4, and 1.31 mg vehicle-1 km-1 respectively. Emission factors of WSII were 0.016 (F-) ~4.17 (Cl-) mg vehicle-1 km-1, totally contributing about 9.8% to the PM2.5 emissions. The sum of 27 measured metal elements accounted for 15.2% of the PM2.5 emissions. Fe was the most abundant metal element, with an emission factor of 3.91 mg vehicle-1 km-1. Emission factors of organic compounds including n-alkanes, PAHs, hopanes, and steranes were 91.9, 5.02, 32.0 and 7.59 μg vehicle-1 km-1, respectively. Stable carbon isotopic composition δ13C value was measured and it was -25.0‰ on average. An isotopic fractionation of 3.2‰ was found during fuel combustion. Compared with a previous study in Zhujiang Tunnel in year 2004, emission factors of PM2.5 mass, EC, OC, WSII except Cl-, and organic compounds decreased by 16.0-93.4%, which could be attributed to emission control policy from 2004 to 2013. However, emission factors of most of the metal elements increased significantly, which could be partially attributed to the changes in motor oil additives and vehicle condition. There are no mandatory national standards to limit metal content from vehicle emission, which should be a concern of the government. A snapshot of the 2013 characteristic emission of PM2.5 and its constituents from on-road vehicular fleet in the PRD region retrieved from our study was found to be useful for the assessment of past and future implementation of vehicle emission control policy.

Chemical and stable carbon isotopic composition of PM2.5 from on-road vehicle emissions in the PRD region and implications for vehicle emission control policy

NASA Astrophysics Data System (ADS)

Dai, S.; Bi, X.; Chan, L. Y.; He, J.; Wang, B.; Wang, X.; Peng, P.; Sheng, G.; Fu, J.

2015-03-01

Vehicle emissions are a major source of urban air pollution. In recent decade, the Chinese government has introduced a range of policies to reduce vehicle emissions. In order to understand the chemical characteristics of PM2.5 from on-road vehicle emissions in the Pearl River Delta (PRD) region and to evaluate the effectiveness of control policies on vehicle emissions, the emission factors of PM2.5 mass, elemental carbon (EC), organic carbon (OC), water-soluble organic carbon (WSOC), water-soluble inorganic ions (WSII), metal elements, organic compounds and stable carbon isotopic composition were measured in the Zhujiang tunnel of Guangzhou, in the PRD region of China in 2013. Emission factors of PM2.5 mass, OC, EC and WSOC were 92.4, 16.7, 16.4 and 1.31 mg vehicle-1 km-1 respectively. Emission factors of WSII were 0.016 (F-) ~ 4.17 (Cl-) mg vehicle-1 km-1, contributing about 9.8% to the PM2.5 emissions. The sum of 27 measured metal elements accounted for 15.2% of PM2.5 emissions. Fe was the most abundant metal element, with an emission factor of 3.91 mg vehicle-1 km-1. Emission factors of organic compounds including n-alkanes, polycyclic aromatic hydrocarbons, hopanes and steranes were 91.9, 5.02, 32.0 and 7.59 μg vehicle-1 km-1, respectively. Stable carbon isotopic composition δ13C value was -25.0‰ on average. An isotopic fractionation of 3.2‰ was found during fuel combustion. Compared to a previous study in Zhujiang tunnel in 2004, emission factors of PM2.5mass, EC, OC, WSII except Cl- and organic compounds decreased by 16.0 ~ 93.4%, which could be attributed to emission control policy from 2004 to 2013. However, emission factors of most of the metal elements increased significantly, which could be partially attributed to the changes in motor oil additives and vehicle conditions. There are no mandatory national standards to limit metal content from vehicle emissions, which should be a concern of the government. A snapshot of the 2013 characteristic emissions of PM2.5 and its constituents from the on-road vehicular fleet in the PRD region retrieved from our study would be helpful for the assessment of past and future implementations of vehicle emission control policy.

Chemical process research and development in the 21st century: challenges, strategies, and solutions from a pharmaceutical industry perspective.

PubMed

Federsel, Hans-Jürgen

2009-05-19

In process research and development (PR&D), the generation and manipulation of small-molecule drugs ranges from bench-scale (laboratory) chemistry to pilot plant manufacture to commercial production. A broad range of disciplines, including process chemistry (organic synthesis), analytical chemistry, process engineering (mass and heat transfer, unit operations), process safety (chemical risk assessment), regulatory compliance, and plant operation, must be effectively applied. In the critical handover between medicinal chemistry and PR&D, compound production is typically scaled up from a few hundred grams to several kilograms. Can the methodologies applied to the former also satisfy the technical, safety, and scalability aspects that come into play in the latter? Occasionally, the transition might occur smoothly, but more often the situation is the opposite: much work and resources must be invested to design a process that is feasible for manufacturing on pilot scale and, eventually, for commercial production. Authentic examples provide enlightening illustrations of dos and don'ts for developing syntheses designed for round-flask operation into production-scale processes. Factors that are easily underestimated or even neglected in the laboratory, such as method robustness, chemical hazards, safety concerns, environmental impact, availability of starting materials and building blocks in bulk quantities, intellectual property (IP) issues, and the final cost of the product, will come into play and need to be addressed appropriately. The decision on which route will be the best for further development is a crucial event and should come into focus early on the R&D timeline. In addition to scientific and technical concerns, the parameter of speed has come to the forefront in the pharmaceutical arena. Although historically the drug industry has tolerated a total time investment of far more than 10 years from idea to market, the current worldwide paradigm requires a reduction to under 10 years for the specific segment covering preclinical development through launch. This change puts enormous pressure on the entire organization, and the implication for PR&D is that the time allowed for conducting route design and scale-up has shrunk accordingly. Furthermore, molecular complexity has become extremely challenging in many instances, and demand steadily grows for process understanding and knowledge generation about low-level byproduct, which often must be controlled even at trace concentrations to meet regulatory specifications (especially in the case of potentially genotoxic impurities). In this Account, we paint a broad picture of the technical challenges the PR&D community is grappling with today, focusing on what measures have been taken over the years to create more efficiency and effectiveness.

Impact of emission control on regional air quality in the Pearl Delta River region, southern China

NASA Astrophysics Data System (ADS)

Wang, N.; Xuejiao, D.

2017-12-01

The Pearl River Delta (PRD) in China has been suffering from air quality issues and the government has implemented a series of strategies in controlling emissions. In an attempt to provide scientific support for improving air quality, the paper investigates the concerning past-to-present air quality data and assesses air quality resulting from emission control. Statistical data revealed that energy consumption doubled from 2004 to 20014 and vehicle usage increased significantly from 2006 to 2014. Due to the effect of control efforts, primary emission of SO2, NOx and PM2.5 decreased resulting in ambient concentrations of SO2, NO2 and PM10 decreased by 66%, 20% and 24%, respectively. However, O3 increased 19% because of the increase of VOC emission. A chemical transport model, the Community Multi-scale Air Quality, was employed to evaluate the responses of nitrate, ammonium, SOA, PM2.5 and O3 to changes in NOx, VOC and NH3 emissions. Three scenarios, a baseline scenario, a CAP scenario (control strength followed as past tendency), and a REF scenario (strict control referred to latest policy and plans), were conducted to investigate the responses and mechanisms. NOx controlling scenarios showed that NOx, nitrate and PM2.5 reduced by 1.8%, 0.7% and 0.2% under CAP and reduced by 7.2%, 1.8% and 0.3% under REF, respectively. The results indicated that reducing NOx emission caused the increase of atmospheric oxidizability, which might result in a compensation of PM2.5 due to the increase of nitrate or sulfate. NH3 controlling scenarios showed that nitrate was sensitive to NH3 emission in PRD, with nitrate decreased by 0 - 10.6% and 0 - 48% under CAP and REF, respectively. Since controlling NH3 emissions not only reduced ammonium but also significantly reduced nitrate, the implement of NH3 controlling strategy was highly suggested. The VOC scenarios revealed that though SOA was not the major component of PM2.5, controlling VOC emission might take effect in southwestern PRD where photochemical pollution usually occurred. Last but not least, the responses of O3 indicated that the PRD was generally VOC-sensitive, while the regime turned to NOx-sensitive in the afternoon, therefore controlling VOC emission could reduce the overall O3 and controlling NOx emission in the afternoon could reduce peak O3.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Perez-Becker, Daniel; Showman, Adam P.

Infrared light curves of transiting hot Jupiters present a trend in which the atmospheres of the hottest planets are less efficient at redistributing the stellar energy absorbed on their daysides—and thus have a larger day-night temperature contrast—than colder planets. To this day, no predictive atmospheric model has been published that identifies which dynamical mechanisms determine the atmospheric heat redistribution efficiency on tidally locked exoplanets. Here we present a shallow-water model of the atmospheric dynamics on synchronously rotating planets that explains why heat redistribution efficiency drops as stellar insolation rises. Our model shows that planets with weak friction and weak irradiationmore » exhibit a banded zonal flow with minimal day-night temperature differences, while models with strong irradiation and/or strong friction exhibit a day-night flow pattern with order-unity fractional day-night temperature differences. To interpret the model, we develop a scaling theory which shows that the timescale for gravity waves to propagate horizontally over planetary scales, τ{sub wave}, plays a dominant role in controlling the transition from small to large temperature contrasts. This implies that heat redistribution is governed by a wave-like process, similar to the one responsible for the weak temperature gradients in the Earth's tropics. When atmospheric drag can be neglected, the transition from small to large day-night temperature contrasts occurs when τ{sub wave}∼√(τ{sub rad}/Ω), where τ{sub rad} is the radiative relaxation time and Ω is the planetary rotation frequency. Alternatively, this transition criterion can be expressed as τ{sub rad} ∼ τ{sub vert}, where τ{sub vert} is the timescale for a fluid parcel to move vertically over the difference in day-night thickness. These results subsume the more widely used timescale comparison for estimating heat redistribution efficiency between τ{sub rad} and the horizontal day-night advection timescale, τ{sub adv}. Only because τ{sub adv} ∼ τ{sub vert} for hot Jupiters does the commonly assumed timescale comparison between τ{sub rad} and τ{sub adv} yield approximately correct predictions for the heat redistribution efficiency.« less

Mode-specific vibrational excitation and energy redistribution after ultrafast intramolecular electron transfer

NASA Astrophysics Data System (ADS)

Hogiu, S.; Werncke, W.; Pfeiffer, M.; Dreyer, J.; Elsaesser, T.

2000-07-01

Vibrational relaxation in the electronic ground state initiated by intramolecular back-electron transfer (b-ET) of betaine-30 (B-30) is studied by picosecond time-resolved anti-Stokes Raman spectroscopy. Measurements were carried out with B-30 dissolved in slowly as well as in rapidly relaxing solvents. We observed a risetime of the Raman band with the highest frequency near 1600 cm-1 which is close to the b-ET time τb-ET of B-30. For B-30 dissolved in propylene carbonate (τb-ET˜1 ps), the population of this mode exhibits a rise time of 1 ps whereas vibrational populations between 400 and 1400 cm-1 increase substantially slower. In contrast, in glycerol triacetin (τb-ET˜3.5 ps) and in ethanol (τb-ET˜6 ps) rise times of all modes are close to the respective b-ET times. Within the first few picoseconds, direct vibrational excitation through b-ET is favored for modes with the highest frequencies and high Franck-Condon factors. Later on, indirect channels of population due to vibrational energy redistribution (IVR) become effective. Thermal equilibrium populations of the Raman active modes are established within 10 to 15 ps after optical excitation.

Influence of Procerum Root Disease on the Water Relations of Eastern White Pine (Pinus strobus L.)

Treesearch

J.R. Butnor; J.R. Seiler; J.A. Gray

2000-01-01

Procerum root disease (PRD) is caused by the deuteromycete fungus Leptogruphium procerum (Kendr.) Wingf, formerly Verticic ladiella procera (Kendr.) and is most commonly isolated from Pinus sp. L., though the fungus has been isolated from other conifer species including Fraser fir (Abies fraseri...

Toward the Prediction of Events in Teachers' Contract Negotiations.

ERIC Educational Resources Information Center

Fris, Joe

This study attempted to formulate a method of assessing teachers' affective states that can predict the course of teacher contract negotiations. Researchers attempted to analyze and quantify teachers' feelings of professional role deprivation (PRD) and attitudinal militancy and to assess the relationship between the two. Professional role…

NLTE steady-state response matrix method.

NASA Astrophysics Data System (ADS)

Faussurier, G.; More, R. M.

2000-05-01

A connection between atomic kinetics and non-equilibrium thermodynamics has been recently established by using a collisional-radiative model modified to include line absorption. The calculated net emission can be expressed as a non-local thermodynamic equilibrium (NLTE) symmetric response matrix. In the paper, this connection is extended to both cases of the average-atom model and the Busquet's model (RAdiative-Dependent IOnization Model, RADIOM). The main properties of the response matrix still remain valid. The RADIOM source function found in the literature leads to a diagonal response matrix, stressing the absence of any frequency redistribution among the frequency groups at this order of calculation.

The CREATE Program Software Applications for the Design and Analysis of Air Vehicles, Naval Vessels, Radio Frequency Antennas, and Ground Vehicles

DTIC Science & Technology

2015-07-10

Kramer noted in the Q4 2010 Earnings Call: “Our innovation engine again delivered in 2010. The percentage of new products in our overall lineup is...their use (not to redistribute the code, reverse engineer it, etc.) and their intended use. They also agree to abide by the ITAR procedures which have

DOE Office of Scientific and Technical Information (OSTI.GOV)

McClements, K. G.; Fredrickson, E. D.

Spherical tokamaks (STs) typically have lower magnetic fields than conventional tokamaks, but similar mass densities. Suprathermal ions with relatively modest energies, in particular beam-injected ions, consequently have speeds close to or exceeding the Alfvén velocity, and can therefore excite a range of Alfvénic instabilities which could be driven by (and affect the behaviour of) fusion α-particles in a burning plasma. STs heated with neutral beams, including the small tight aspect ratio tokamak (START), the mega amp spherical tokamak (MAST), the national spherical torus experiment (NSTX) and Globus-M, have thus provided an opportunity to study toroidal Alfvén eigenmodes (TAEs), together withmore » higher frequency global Alfvén eigenmodes (GAEs) and compressional Alfvén eigenmodes (CAEs), which could affect beam current drive and channel fast ion energy into bulk ions in future devices. In NSTX GAEs were correlated with a degradation of core electron energy confinement. In MAST pulses with reduced magnetic field, CAEs were excited across a wide range of frequencies, extending to the ion cyclotron range, but were suppressed when hydrogen was introduced to the deuterium plasma, apparently due to mode conversion at ion–ion hybrid resonances. At lower frequencies fishbone instabilities caused fast particle redistribution in some MAST and NSTX pulses, but this could be avoided by moving the neutral beam line away from the magnetic axis or by operating the plasma at either high density or elevated safety factor. Fast ion redistribution has been observed during GAE avalanches on NSTX, while in both NSTX and MAST fast ions were transported by saturated kink modes, sawtooth crashes, resonant magnetic perturbations and TAEs. The energy dependence of fast ion redistribution due to both sawteeth and TAEs has been studied in Globus-M. High energy charged fusion products are unconfined in present-day STs, but have been shown in MAST to provide a useful diagnostic of beam ion behaviour, supplementing the information provided by neutron detectors. In MAST electrons were accelerated to highly suprathermal energies as a result of edge localised modes, while in both MAST and NSTX ions were accelerated due to internal reconnection events. Lastly, ion acceleration has also been observed during merging-compression start-up in MAST.« less

Energetic particles in spherical tokamak plasmas

NASA Astrophysics Data System (ADS)

McClements, K. G.; Fredrickson, E. D.

2017-05-01

Spherical tokamaks (STs) typically have lower magnetic fields than conventional tokamaks, but similar mass densities. Suprathermal ions with relatively modest energies, in particular beam-injected ions, consequently have speeds close to or exceeding the Alfvén velocity, and can therefore excite a range of Alfvénic instabilities which could be driven by (and affect the behaviour of) fusion α-particles in a burning plasma. STs heated with neutral beams, including the small tight aspect ratio tokamak (START), the mega amp spherical tokamak (MAST), the national spherical torus experiment (NSTX) and Globus-M, have thus provided an opportunity to study toroidal Alfvén eigenmodes (TAEs), together with higher frequency global Alfvén eigenmodes (GAEs) and compressional Alfvén eigenmodes (CAEs), which could affect beam current drive and channel fast ion energy into bulk ions in future devices. In NSTX GAEs were correlated with a degradation of core electron energy confinement. In MAST pulses with reduced magnetic field, CAEs were excited across a wide range of frequencies, extending to the ion cyclotron range, but were suppressed when hydrogen was introduced to the deuterium plasma, apparently due to mode conversion at ion-ion hybrid resonances. At lower frequencies fishbone instabilities caused fast particle redistribution in some MAST and NSTX pulses, but this could be avoided by moving the neutral beam line away from the magnetic axis or by operating the plasma at either high density or elevated safety factor. Fast ion redistribution has been observed during GAE avalanches on NSTX, while in both NSTX and MAST fast ions were transported by saturated kink modes, sawtooth crashes, resonant magnetic perturbations and TAEs. The energy dependence of fast ion redistribution due to both sawteeth and TAEs has been studied in Globus-M. High energy charged fusion products are unconfined in present-day STs, but have been shown in MAST to provide a useful diagnostic of beam ion behaviour, supplementing the information provided by neutron detectors. In MAST electrons were accelerated to highly suprathermal energies as a result of edge localised modes, while in both MAST and NSTX ions were accelerated due to internal reconnection events. Ion acceleration has also been observed during merging-compression start-up in MAST.

Clusters of Defects in Semiconductors

DTIC Science & Technology

1984-08-01

onecionbewen-te heica seces .-. o* Fe and.th deec prd *n th *Rlmnecne ae t..* E. STATISTICS The funds from this contract were used to support the research of...characterized at Hughes Research Laboratories. L x No Np N1 . Electron X-ray Sample (cm- 1) (cm- ) (cm-3 ) microprobe Density diffraction .. -. C077 3.6x 10

Tractor-mounted, GPS-based spot fumigation system manages Prunus replant disease

USDA-ARS?s Scientific Manuscript database

Our research goal was to use recent advances in global positioning system (GPS) and computer technology to apply just the right amount of fumigant where it is most needed (i.e., in a small target treatment zone in and around each tree replanting site) to control Prunus replant disease (PRD). We deve...

Development of cryogenic PRD-49-1 filament-wound tanks

NASA Technical Reports Server (NTRS)

Hoggatt, J. T.

1971-01-01

A high modulus polymeric fiber was evaluated as a reinforcement for filament wound pressure vessels. Winding parameters and design data were established for the fiber with two different epoxy resin systems. Comparison was made between the performance factors of the polymeric fiber and those of S-glass and high modulus graphite vessels.

An investigation of the compressive strength of PRD-49-3/Epoxy composites

NASA Technical Reports Server (NTRS)

Kulkarni, S. V.; Rice, J. S.; Rosen, B. W.

1973-01-01

The development of unidirectional fiber composite materials is discussed. The mechanical and physical properties of the materials are described. Emphasis is placed in analyzing the compressive behavior of composite materials and developing methods for increasing compressive strength. The test program for evaluating the various procedures for improving compressive strength are reported.

76 FR 48485 - Medicare Program; Prospective Payment System and Consolidated Billing for Skilled Nursing...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-08

... order below: ABN Advance Beneficiary Notice AIDS Acquired Immune Deficiency Syndrome ARD Assessment... Survey Certification and Reporting System PAC-PRD Post Acute Care Payment Reform Demonstration PECOS... which the hospital can use its beds to provide either acute or SNF care, as needed. For critical [[Page...

78 FR 27416 - Notice of Availability of the Final Record of Decision for the Programmatic Environmental Impact...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-10

... improved personal radiation detectors (PRD), RIDs, and NII tools, such as high-energy container scanners... DEPARTMENT OF HOMELAND SECURITY U.S. Customs and Border Protection Notice of Availability of the... Border Activities AGENCY: U.S. Customs and Border, Protection, DHS. ACTION: Notice of availability...

Sources of excess urban carbonaceous aerosol in the Pearl River delta region, China

EPA Science Inventory

Carbonaceous aerosol is one of the important constituents of fine particulate matter (PM2.5) in Southern China, including the Pearl River Delta (PRD) region and Hong Kong (HK). During the study period (October and December of 2002, and March and June of 2003), the monthly average...

Poor Performance on Serial Visual Tasks in Persons with Reading Disabilities: Impaired Working Memory?

ERIC Educational Resources Information Center

Ram-Tsur, Ronit; Faust, Miriam; Zivotofsky, Ari Z.

2008-01-01

The present study investigates the performance of persons with reading disabilities (PRD) on a variety of sequential visual-comparison tasks that have different working-memory requirements. In addition, mediating relationships between the sequential comparison process and attention and memory skills were looked for. Our findings suggest that PRD…

Regular consumption of fresh orange juice increases human skin carotenoid content.

PubMed

Massenti, Roberto; Perrone, Anna; Livrea, Maria Antonietta; Lo Bianco, Riccardo

2015-01-01

Dermal carotenoids are a good indicator of antioxidant status in the body. This study aimed to determine whether regular consumption of orange juice could increase dermal carotenoids. Two types of orange juice, obtained from regularly (CI) and partially (PRD) irrigated trees, were tested to reveal any possible association between juice and dermal carotenoids. Soluble solids, titratable acidity, and total carotenoids were quantified in the juice; skin carotenoid score (SCS) was assessed by Raman spectroscopy. Carotenoid content was 7.3% higher in PRD than in CI juice, inducing no difference in SCS. In a first trial with daily juice intakes for 25 days, SCS increased linearly (10%) in the individual with higher initial SCS, and exponentially (15%) in the individual with lower initial SCS. In a second trial, SCS showed a 6.5% increase after 18 days of drinking juice every other day, but returned to initial values three days after last intake. Skin carotenoids can be increased by regular consumption of fresh orange juice, while their persistence may depend on the accumulation level, environmental conditions or living habits.

Giving raw data a chance to talk: a demonstration of exploratory visual analytics with a pediatric research database using Microsoft Live Labs Pivot to promote cohort discovery, research, and quality assessment.

PubMed

Viangteeravat, Teeradache; Nagisetty, Naga Satya V Rao

2014-01-01

Secondary use of large and open data sets provides researchers with an opportunity to address high-impact questions that would otherwise be prohibitively expensive and time consuming to study. Despite the availability of data, generating hypotheses from huge data sets is often challenging, and the lack of complex analysis of data might lead to weak hypotheses. To overcome these issues and to assist researchers in building hypotheses from raw data, we are working on a visual and analytical platform called PRD Pivot. PRD Pivot is a de-identified pediatric research database designed to make secondary use of rich data sources, such as the electronic health record (EHR). The development of visual analytics using Microsoft Live Labs Pivot makes the process of data elaboration, information gathering, knowledge generation, and complex information exploration transparent to tool users and provides researchers with the ability to sort and filter by various criteria, which can lead to strong, novel hypotheses.

Sources of ambient volatile organic compounds and their contributions to photochemical ozone formation at a site in the Pearl River Delta, southern China.

PubMed

Ling, Z H; Guo, H; Cheng, H R; Yu, Y F

2011-10-01

The Positive Matrix Factorization (PMF) receptor model and the Observation Based Model (OBM) were combined to analyze volatile organic compound (VOC) data collected at a suburban site (WQS) in the PRD region. The purposes are to estimate the VOC source apportionment and investigate the contributions of these sources and species of these sources to the O(3) formation in PRD. Ten VOC sources were identified. We further applied the PMF-extracted concentrations of these 10 sources into the OBM and found "solvent usage 1", "diesel vehicular emissions" and "biomass/biofuel burning" contributed most to the O(3) formation at WQS. Among these three sources, higher Relative Incremental Reactivity (RIR)-weighted values of ethene, toluene and m/p-xylene indicated that they were mainly responsible for local O(3) formation in the region. Sensitivity analysis revealed that the sources of "diesel vehicular emissions", "biomass/biofuel burning" and "solvent usage 1" had low uncertainties whereas "gasoline evaporation" showed the highest uncertainty. Copyright © 2011 Elsevier Ltd. All rights reserved.

Sequential ASE extraction of alkylphenols from sediments: Occurrence and environmental implications.

PubMed

Gong, Jian; Xu, Lei; Yang, Yu; Chen, Di-Yun; Ran, Yong

2011-08-30

The occurrence of alkylphenols (APs) including nonylphenol (NP) and octylphenol (OP) in the riverine sediments from the Pearl River Delta (PRD), South China was investigated and compared by Soxhlet extraction (S-APs) with dichloromethane and by sequential accelerated solvent extraction (ASE) (A-APs) with 1:6 toluene/methanol, respectively. Concentrations of OP and NP range from <1 to 463ng/g dw and 31-21,885ng/g dw, respectively, demonstrating that the contamination level of APs in the PRD is one of the highest in the world. Moreover, the A-APs contents are highly significantly related to and on average 1.5 times the S-APs contents. For sequential two ASE extractions, APs in the first extract accounts for 82.2-99.2% of their total contents in the sequential two extractions. The correlation analysis shows that S-APs and A-APs are both significantly associated with the contents of total organic carbon (TOC), suggesting that the variable extraction efficiency of these two methods is related to the presence of condensed organic matter in the sediments. Copyright © 2011 Elsevier B.V. All rights reserved.

Virucidal properties of metal oxide nanoparticles and their halogen adducts.

PubMed

Häggström, Johanna; Balyozova, Denitza; Klabunde, Kenneth J; Marchin, George

2010-04-01

Selected metal oxide nanoparticles are capable of strongly adsorbing large amounts of halogens (Cl(2), Br, I(2)) and mixed halogens. These solid adducts are relatively stable thermally, and they can be stored for long periods. However, in the open environment, they are potent biocides. Herein are described studies with a number of bacteriophage MS2, phiX174, and PRD-1 (virus examples). PRD-1 is generally more resistant to chemical disinfection, but in this paper it is shown to be very susceptible to selected interhalogen and iodine adducts of CeO(2), Al(2)O(3), and TiO(2) nanoparticles. Overall, the halogen adducts of TiO(2) and Al(2)O(3) were most effective. The mechanism of disinfection by these nanoparticles is not completely clear, but could include abrasive properties, as well as oxidative powers. A hypothesis that nanoparticles damage virons or stick to them and prevent binding to the host cell is a consideration that needs to be explored. Herein are reported comparative biocidal activities of a series of adducts and electron microscope images of before and after treatment.

Persistent halogenated compounds in fish from rivers in the Pearl River Delta, South China: Geographical pattern and implications for anthropogenic effects on the environment.

PubMed

Sun, Runxia; Luo, Xiaojun; Tang, Bin; Li, Zongrui; Wang, Tao; Tao, Lin; Mai, Bixian

2016-04-01

Three fish species, mud carp (Cirrhinus molitorella), tilapia (Tilapia nilotica), and plecostomus (Hypostomus plecostomus), from rivers in the Pearl River Delta (PRD) were analyzed for dichlorodiphenyltrichloroethane and its metabolites (DDTs), hexachlorocyclohexanes (HCHs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), decabromodiphenyl ethane (DBDPE), and Dechlorane Plus (DP). The concentrations of DDTs, HCHs, PCBs, PBDEs, DBDPE, and DP ranged from 380-57,000, 5.5-100, 30-4200, 6.9-690, 0.29-460, and 0.09-20ng/g lipid weight, respectively. Congener profiles or chemical compositions of PBDEs, DPs, DDTs, and HCHs in plecostomus differed significantly from those in the other two fish species, which can be ascribed to species-specific metabolism. DDTs derived from historical residue and land erosion remained the predominant pollutants in the PRD, while industrial and urban activities resulted in elevated levels of PCBs and PBDEs in the metropolitan area. E-waste recycling activities have greatly impacted on the adjacent aquatic environment, and the potential point source for DBDPE was also revealed. Copyright © 2016 Elsevier Inc. All rights reserved.

Giving Raw Data a Chance to Talk: A Demonstration of Exploratory Visual Analytics with a Pediatric Research Database Using Microsoft Live Labs Pivot to Promote Cohort Discovery, Research, and Quality Assessment

PubMed Central

Viangteeravat, Teeradache; Nagisetty, Naga Satya V. Rao

2014-01-01

Secondary use of large and open data sets provides researchers with an opportunity to address high-impact questions that would otherwise be prohibitively expensive and time consuming to study. Despite the availability of data, generating hypotheses from huge data sets is often challenging, and the lack of complex analysis of data might lead to weak hypotheses. To overcome these issues and to assist researchers in building hypotheses from raw data, we are working on a visual and analytical platform called PRD Pivot. PRD Pivot is a de-identified pediatric research database designed to make secondary use of rich data sources, such as the electronic health record (EHR). The development of visual analytics using Microsoft Live Labs Pivot makes the process of data elaboration, information gathering, knowledge generation, and complex information exploration transparent to tool users and provides researchers with the ability to sort and filter by various criteria, which can lead to strong, novel hypotheses. PMID:24808811

Frequency, thermal and voltage supercapacitor characterization and modeling

NASA Astrophysics Data System (ADS)

Rafik, F.; Gualous, H.; Gallay, R.; Crausaz, A.; Berthon, A.

A simple electrical model has been established to describe supercapacitor behaviour as a function of frequency, voltage and temperature for hybrid vehicle applications. The electrical model consists of 14 RLC elements, which have been determined from experimental data using electrochemical impedance spectroscopy (EIS) applied on a commercial supercapacitor. The frequency analysis has been extended for the first time to the millihertz range to take into account the leakage current and the charge redistribution on the electrode. Simulation and experimental results of supercapacitor charge and discharge have been compared and analysed. A good correlation between the model and the EIS results has been demonstrated from 1 mHz to 1 kHz, from -20 to 60 °C and from 0 to 2.5 V.

Assessment of major ions and heavy metals in groundwater: a case study from Guangzhou and Zhuhai of the Pearl River Delta, China

NASA Astrophysics Data System (ADS)

Lu, Yintao; Tang, Changyuan; Chen, Jianyao; Yao, Hong

2016-06-01

Anthropogenic activities in the Pearl River Delta (PRD) have caused a deterioration of groundwater quality over the past twenty years as a result of rapid urbanization and industrial development. In this study, the hydrochemical characteristics, quality, and sources of heavy metals in the groundwater of the PRD were investigated. Twenty-five groundwater samples were collected and analyzed for pH, electrical conductivity (EC), total dissolved solids (TDS), δ18O, δ2H, major ions, and heavy metals. The groundwater was slightly acidic and presented TDS values that ranged from 35.5 to 8,779.3 mg·L-1. The concentrations of the major ions followed the order Cl->HCO 3 - >Na+>SO 4 2- >NO 3 - >NH 4 + >Ca2+>K+>Mg2+>Fe2+/3+>Al3+. Ca-Mg-HCO3 and Na-K-HCO3 were the predominant types of facies, and the chemical composition of the groundwater was primarily controlled by chemical weathering of the basement rocks, by mixing of freshwater and seawater and by anthropogenic activities. The heavy metal pollution index (HPI) indicated that 64% of the samples were in the low category, 16% were in the medium category and 20% were in the high category, providing further evidence that this groundwater is unsuitable for drinking. Lead, arsenic, and manganese were mainly sourced from landfill leachate; cadmium from landfill leachate and agricultural wastes; mercury from the discharge of leachate associated with mining activities and agricultural wastes; and chromium primarily from industrial wastes. According to the irrigation water quality indicators, the groundwater in the PRD can be used for irrigation in most farmland without strong negative impacts. However, approximately 9 million people in the Guangdong Province are at risk due to the consumption of untreated water. Therefore, we suggest that treating the groundwater to achieve safer levels is necessary.

Characterizing and sourcing ambient PM2.5 over key emission regions in China II: Organic molecular markers and CMB modeling

NASA Astrophysics Data System (ADS)

Zhou, Jiabin; Xiong, Ying; Xing, Zhenyu; Deng, Junjun; Du, Ke

2017-08-01

From November 2012 to July 2013, a sampling campaign was completed for comprehensive characterization of PM2.5 over four key emission regions in China: Beijing-Tianjin-Hebei (BTH), Yangzi River Delta (YRD), Pearl River Delta (PRD), and Sichuan Basin (SB). A multi-method approach, adopting different analytical and receptor modeling methods, was employed to determine the relative abundances of region-specific air pollution constituents and contributions of emission sources. This paper is focused on organic molecular marker based source apportionment using chemical mass balance (CMB) receptor modeling. Analyses of the organic molecular markers revealed that vehicle emission, coal combustion, biomass burning, meat cooking and natural gas combustion were the major contributors to organic carbon (OC) in PM2.5. The vehicle emission dominated the sources contributing to OC in spring at four sampling sites. During wintertime, the coal combustion had highest contribution to OC at BTH site, while the major source contributing to OC at YRD and PRD sites was vehicle emission. In addition, the relative contributions of different emission sources to PM2.5 mass at a specific location site and in a specific season revealed seasonal and spatial variations across all four sampling locations. The largest contributor to PM2.5 mass was secondary sulfate (14-17%) in winter at the four sites. The vehicle emission was found to be the major source (14-21%) for PM2.5 mass at PRD site. The secondary ammonium has minor variation (4-5%) across the sites, confirming the influences of regional emission sources on these sites. The distinct patterns of seasonal and spatial variations of source apportionment observed in this study were consistent with the findings in our previous paper based upon water-soluble ions and carbonaceous fractions. This makes it essential for the local government to make season- and region-specific mitigation strategies for abating PM2.5 pollution in China.

To what extent can China’s near-term air pollution control policy protect air quality and human health? A case study of the Pearl River Delta region

NASA Astrophysics Data System (ADS)

Jiang, Xujia; Hong, Chaopeng; Zheng, Yixuan; Zheng, Bo; Guan, Dabo; Gouldson, Andy; Zhang, Qiang; He, Kebin

2015-10-01

Following a series of extreme air pollution events, the Chinese government released the Air Pollution Prevention and Control Action Plan in 2013 (China’s State Council 2013). The Action Plan sets clear goals for key regions (i.e. cities above the prefecture level, Beijing-Tianjin-Hebei Province, the Yangtze River Delta and the Pearl River Delta) and establishes near-term control efforts for the next five years. However, the extent to which the Action Plan can direct local governments’ activities on air pollution control remains unknown. Here we seek to evaluate the air quality improvement and associated health benefits achievable under the Action Plan in the Pearl River Delta (PRD) area from 2012 to 2017. Measure-by-measure quantification results show that the Action Plan would promise effective emissions reductions of 34% of SO2, 28% of NOx, 26% of PM2.5 (particulate matter less than 2.5 μm in diameter), and 10% of VOCs (volatile organic compounds). These emissions abatements would lower the PM2.5 concentration by 17%, surpassing the 15% target established in the Action Plan, thereby avoiding more than 2900 deaths and 4300 hospital admissions annually. We expect the implementation of the Action Plan in the PRD would be productive; the anticipated impacts, however, fall short of the goal of protecting the health of local residents, as there are still more than 33 million people living in places where the annual mean ambient PM2.5 concentrations are greater than 35 μg m-3, the interim target-3 of the World Health Organization (WHO). We therefore propose the next steps for air pollution control that are important not only for the PRD but also for all other regions of China as they develop and implement effective air pollution control policies.

Characterization of beam-driven instabilities and current redistribution in MST plasmas

NASA Astrophysics Data System (ADS)

Parke, E.

2015-11-01

A unique, high-rep-rate (>10 kHz) Thomson scattering diagnostic and a high-bandwidth FIR interferometer-polarimeter on MST have enabled characterization of beam-driven instabilities and magnetic equilibrium changes observed during high power (1 MW) neutral beam injection (NBI). While NBI leads to negligible net current drive, an increase in on-axis current density observed through Faraday rotation is offset by a reduction in mid-radius current. Identification of the phase flip in temperature fluctuations associated with tearing modes provides a sensitive measure of rational surface locations. This technique strongly constrains the safety factor for equilibrium reconstruction and provides a powerful new tool for measuring the equilibrium magnetic field. For example, the n = 6 temperature structure is observed to shift inward 1.1 +/- 0.6 cm, with an estimated reduction of q0 by 5%. This is consistent with a mid-radius reduction in current, and together the Faraday rotation and Thomson scattering measurements corroborate an inductive redistribution of current that compares well with TRANSP/MSTFit predictions. Interpreting tearing mode temperature structures in the RFP remains challenging; the effects of multiple, closely-spaced tearing modes on the mode phase measurement require further verification. In addition to equilibrium changes, previous work has shown that the large fast ion population drives instabilities at higher frequencies near the Alfvén continuum. Recent observations reveal a new instability at much lower frequency (~7 kHz) with strongly chirping behavior. It participates in extensive avalanches of the higher frequency energetic particle and Alfvénic modes to drive enhanced fast ion transport. Internal structures measured from Te and ne fluctuations, their dependence on the safety factor, as well as frequency scaling motivate speculation about mode identity. Work supported by U.S. DOE.

Extraction and Analysis of Impervious Surfaces Based on a Spectral Un-Mixing Method Using Pearl River Delta of China Landsat TM/ETM+ Imagery from 1998 to 2008

PubMed Central

Deng, Yingbin; Fan, Fenglei; Chen, Renrong

2012-01-01

Impervious surface area (ISA) is considered as an indicator of environment change and is regarded as an important input parameter for hydrological cycle simulation, water management and area pollution assessment. The Pearl River Delta (PRD), the 3rd most important economic district of China, is chosen in this paper to extract the ISA information based on Landsat images of 1998, 2003 and 2008 by using a linear spectral un-mixing method and to monitor impervious surface change by analyzing the multi-temporal Landsat-derived fractional impervious surface. Results of this study were as follows: (1) the area of ISA in the PRD increased 79.09% from 1998 to 2003 and 26.88% from 2003 to 2008 separately; (2) the spatial distribution of ISA was described according to the 1998/2003 percentage respectively. Most of middle and high percentage ISA was located in northwestern and southeastern of the whole delta, and middle percentage ISA was mainly located in the city interior, high percentage ISA was mainly located in the suburban around the city accordingly; (3) the expanding direction and trend of high percentage ISA was discussed in order to understand the change of urban in this delta; High percentage ISA moved from inner city to edge of urban area during 1998–2003 and moved to the suburban area that far from the urban area mixed with jumpily and gradually during 2003–2008. According to the discussion of high percentage ISA spatial expanded direction, it could be found out that high percentage ISA moved outward from the centre line of Pearl River of the whole delta while a high ISA percentage in both shores of the Pearl River Estuary moved toward the Pearl River; (4) combining the change of ISA with social conditions, the driving relationship was analyzed in detail. It was evident that ISA percentage change had a deep relationship with the economic development of this region in the past ten years. Contemporaneous major sport events (16th Asia Games of Guangzhou, 26th Summer Universidad of Shenzhen) and the government policies also promoted the development of the ISA. Meanwhile, topographical features like the National Nature Reserve of China restricted and affected the expansion of the ISA. Above all, this paper attempted to extract ISA in a major region of the PRD; the temporal and spatial analyses to PRD ISA demonstrated the drastic changes in developed areas of China. These results were important and valuable for land use management, ecological protection and policy establishment. PMID:22438741

A modeling study on the effect of urban land surface forcing to regional meteorology and air quality over South China

NASA Astrophysics Data System (ADS)

Zhu, Kuanguang; Xie, Min; Wang, Tijian; Cai, Junxiong; Li, Songbing; Feng, Wen

2017-03-01

The change of land-use from natural to artificial surface induced by urban expansion can deeply impact the city environment. In this paper, the model WRF/Chem is applied to explore the effect of this change on regional meteorology and air quality over South China, where people have witnessed a rapid rate of urbanization. Two sets of urban maps are adopted to stand for the pre-urbanization and the present urban land-use distributions. Month-long simulations are conducted for January and July, 2014. The results show that urban expansion can obviously change the weather conditions around the big cities of South China. Especially in the Pearl River Delta region (PRD), the urban land-use change can increase the sensible heat flux by 40 W/m2 in January and 80 W/m2 in July, while decrease the latent heat flux about -50 W/m2 in January and -120 W/m2 in July. In the consequent, 2-m air temperature (T2) increases as much as 1 °C and 2 °C (respective to January and July), planetary boundary layer height (PBLH) rises up by 100-150 m and 300 m, 10-m wind speed (WS10) decreases by -1.2 m/s and -0.3 m/s, and 2-m specific humidity is reduced by -0.8 g/kg and -1.5 g/kg. Also, the precipitation in July can be increased as much as 120 mm, with more heavy rains and rainstorms. These variations of meteorological factors can significantly impact the spatial and vertical distribution of air pollutants as well. In PRD, the enhanced updraft can reduce the surface concentrations of PM10 by -40 μg/m3 (30%) in January and -80 μg/m3 (50%) in July, but produce a correlating increase in the concentrations at higher atmospheric layers. However, according to the increase in T2 and the decrease in surface NO, the surface concentrations of O3 in PRD can increase by 2-6 ppb in January and 8-12 ppb in July. Meanwhile, there is a significant increase in the O3 concentrations at upper layers above PRD, which should be attributed to the increase in air temperature and the enhanced upward transport of O3 and its precursors. As for some relative small cities, such as Haikou, there is very little variation in surface PM10 and O3 in both months, implying less urbanization in these areas. Moreover, the depletion of O3 by NO may be the main cause of the reduction of O3 at upper layers in these small cities.

Extraction and analysis of impervious surfaces based on a spectral un-mixing method using Pearl River Delta of China Landsat TM/ETM+ imagery from 1998 to 2008.

PubMed

Deng, Yingbin; Fan, Fenglei; Chen, Renrong

2012-01-01

Impervious surface area (ISA) is considered as an indicator of environment change and is regarded as an important input parameter for hydrological cycle simulation, water management and area pollution assessment. The Pearl River Delta (PRD), the 3rd most important economic district of China, is chosen in this paper to extract the ISA information based on Landsat images of 1998, 2003 and 2008 by using a linear spectral un-mixing method and to monitor impervious surface change by analyzing the multi-temporal Landsat-derived fractional impervious surface. Results of this study were as follows: (1) the area of ISA in the PRD increased 79.09% from 1998 to 2003 and 26.88% from 2003 to 2008 separately; (2) the spatial distribution of ISA was described according to the 1998/2003 percentage respectively. Most of middle and high percentage ISA was located in northwestern and southeastern of the whole delta, and middle percentage ISA was mainly located in the city interior, high percentage ISA was mainly located in the suburban around the city accordingly; (3) the expanding direction and trend of high percentage ISA was discussed in order to understand the change of urban in this delta; High percentage ISA moved from inner city to edge of urban area during 1998-2003 and moved to the suburban area that far from the urban area mixed with jumpily and gradually during 2003-2008. According to the discussion of high percentage ISA spatial expanded direction, it could be found out that high percentage ISA moved outward from the centre line of Pearl River of the whole delta while a high ISA percentage in both shores of the Pearl River Estuary moved toward the Pearl River; (4) combining the change of ISA with social conditions, the driving relationship was analyzed in detail. It was evident that ISA percentage change had a deep relationship with the economic development of this region in the past ten years. Contemporaneous major sport events (16th Asia Games of Guangzhou, 26th Summer Universidad of Shenzhen) and the government policies also promoted the development of the ISA. Meanwhile, topographical features like the National Nature Reserve of China restricted and affected the expansion of the ISA. Above all, this paper attempted to extract ISA in a major region of the PRD; the temporal and spatial analyses to PRD ISA demonstrated the drastic changes in developed areas of China. These results were important and valuable for land use management, ecological protection and policy establishment.

Prospects of Using High-Intensity THz Pulses To Induce Ultrafast Temperature-Jumps in Liquid Water.

PubMed

Mishra, Pankaj Kr; Bettaque, Vincent; Vendrell, Oriol; Santra, Robin; Welsch, Ralph

2018-06-01

Ultrashort, high-intensity terahertz (THz) pulses, e.g., generated at free-electron laser facilities, allow for direct investigation as well as the driving of intermolecular modes in liquids like water and thus will deepen our understanding of the hydrogen bonding network. In this work, the temperature-jump (T-jump) of water induced by THz radiation is simulated for ten different THz frequencies in the range from 3 to 30 THz and five different pulse intensities in the range from 1 × 10 11 to 5 × 10 12 W/cm 2 employing both ab initio molecular dynamics (AIMD) and force field molecular dynamics (FFMD) approaches. The most efficient T-jump can be achieved with 16 THz pulses. Three distinct T-jump mechanisms can be uncovered. For all cases, the T-jump mechanism proceeds within tens of femtoseconds (fs). For frequencies between 10 and 25 THz, most of the energy is initially transferred to the rotational degrees of freedom. Subsequently, the energy is redistributed to the translational and intramolecular vibrational degrees of freedom within a maximum of 500 fs. For the lowest frequencies considered (7 THz and below), translational and rotational degrees of freedom are heated within tens of fs as the THz pulse also couples to the intermolecular vibrations. Subsequently, the intramolecular vibrational modes are heated within a few hundred fs. At the highest frequencies considered (25 THz and above), vibrational and rotational degrees of freedom are heated within tens of fs, and energy redistribution to the translational degrees of freedom happens within several hundred fs. Both AIMD and FFMD simulations show a similar dependence of the T-jump on the frequency employed. However, the FFMD simulations overestimate the total energy transfer around the main peak and drop off too fast toward frequencies higher and lower than the main peak. These differences can be rationalized by missing elements, such as the polarizability, in the TIP4P/2005f force field employed. The feasibility of performing experiments at the studied frequencies and intensities as well as important issues such as energy efficiency, penetration depth, and focusing are discussed.

Transport and fate of viruses in sediment and stormwater from a managed aquifer recharge site

USDA-ARS?s Scientific Manuscript database

Enteric viruses are one of the major concerns in water reclamation and reuse at managed aquifer recharge (MAR) sites. In this study, the transport and fate of bacteriophages MS2, PRD1, and FX174 were studied in sediment and stormwater (SW) collected from a MAR site in Parafield, Australia. Column ex...

Effects of Cluster Sets and Rest-Redistribution on Mechanical Responses to Back Squats in Trained Men.

PubMed

Tufano, James J; Conlon, Jenny A; Nimphius, Sophia; Brown, Lee E; Petkovic, Alex; Frick, Justin; Haff, G Gregory

2017-09-01

Eight resistance-trained men completed three protocols separated by 48-96 hours. Each protocol included 36 repetitions with the same rest duration, but the frequency and length of rest periods differed. The cluster sets of four (CS4) protocol included 30 s of rest after the 4th, 8th, 16th, 20th, 28th, and 32nd repetition in addition to 120 s of rest after the 12th and 24th repetition. For the other two protocols, the total 420 s rest time of CS4 was redistributed to include nine sets of four repetitions (RR4) with 52.5 s of rest after every four repetitions, or 36 sets of single repetitions (RR1) with 12 s of rest after every repetition. Mean (MF) and peak (PF) force, velocity (MV and PV), and power output (MP and PP) were measured during 36 repetitions and were collapsed into 12 repetitions for analysis. Repeated measures ANOVA 3 (protocol) x 12 (repetition) showed a protocol x repetition interaction for PF, MV, PV, MP, and PP (p-values from <0.001 to 0.012). No interaction or main effect was present for MF. During RR1, MV, PV, MP, and PP were maintained, but decreased throughout every 4-repetition sequence during CS4 and RR4. During CS4 and RR4, PF was less following a rest period compared to subsequent repetitions, whereas PF was maintained during RR1. These data indicate that rest redistribution results in similar average kinetics and kinematics, but if total rest time is redistributed to create shorter but more frequent sets, kinetics and kinematics may remain more constant.

Effects of Cluster Sets and Rest-Redistribution on Mechanical Responses to Back Squats in Trained Men

PubMed Central

Tufano, James J.; Conlon, Jenny A.; Nimphius, Sophia; Brown, Lee E.; Petkovic, Alex; Frick, Justin; Haff, G. Gregory

2017-01-01

Abstract Eight resistance-trained men completed three protocols separated by 48-96 hours. Each protocol included 36 repetitions with the same rest duration, but the frequency and length of rest periods differed. The cluster sets of four (CS4) protocol included 30 s of rest after the 4th, 8th, 16th, 20th, 28th, and 32nd repetition in addition to 120 s of rest after the 12th and 24th repetition. For the other two protocols, the total 420 s rest time of CS4 was redistributed to include nine sets of four repetitions (RR4) with 52.5 s of rest after every four repetitions, or 36 sets of single repetitions (RR1) with 12 s of rest after every repetition. Mean (MF) and peak (PF) force, velocity (MV and PV), and power output (MP and PP) were measured during 36 repetitions and were collapsed into 12 repetitions for analysis. Repeated measures ANOVA 3 (protocol) x 12 (repetition) showed a protocol x repetition interaction for PF, MV, PV, MP, and PP (p-values from <0.001 to 0.012). No interaction or main effect was present for MF. During RR1, MV, PV, MP, and PP were maintained, but decreased throughout every 4-repetition sequence during CS4 and RR4. During CS4 and RR4, PF was less following a rest period compared to subsequent repetitions, whereas PF was maintained during RR1. These data indicate that rest redistribution results in similar average kinetics and kinematics, but if total rest time is redistributed to create shorter but more frequent sets, kinetics and kinematics may remain more constant. PMID:28828076

Importance of biologically active aurora-like ultraviolet emission: stochastic irradiation of Earth and Mars by flares and explosions.

PubMed

Smith, David S; Scalo, John; Wheeler, J Craig

2004-10-01

Habitable planets will be subject to intense sources of ionizing radiation and fast particles from a variety of sources--from the host star to distant explosions--on a variety of timescales. Monte Carlo calculations of high-energy irradiation suggest that the surfaces of terrestrial-like planets with thick atmospheres (column densities greater than about 100 g cm(-2)) are well protected from directly incident X-rays and gamma-rays, but we find that sizeable fractions of incident ionizing radiation from astrophysical sources can be redistributed to biologically and chemically important ultraviolet wavelengths, a significant fraction of which can reach the surface. This redistribution is mediated by secondary electrons, resulting from Compton scattering and X-ray photoabsorption, the energies of which are low enough to excite and ionize atmospheric molecules and atoms, resulting in a rich aurora-like spectrum. We calculate the fraction of energy redistributed into biologically and chemically important wavelength regions for spectra characteristic of stellar flares and supernovae using a Monte-Carlo transport code and then estimate the fraction of this energy that is transmitted from the atmospheric altitudes of redistribution to the surface for a few illustrative cases. For atmospheric models corresponding to the Archean Earth, we assume no significant ultraviolet absorbers, only Rayleigh scattering, and find that the fraction of incident ionizing radiation that is received at the surface in the form of redistributed ultraviolet in the biologically relevant 200-320 nm region (UV-C and UV-B bands) can be up to 4%. On the present-day Earth with its ultraviolet ozone shield, this fraction is found to be 0.2%. Both values are many orders of magnitude higher than the fraction of direct ionizing radiation reaching the surface. This result implies that planetary organisms will be subject to mutationally significant, if intermittent, fluences of UV-B and harder radiation even in the presence of a narrow-band ultraviolet shield like ozone. We also calculate the surficial transmitted fraction of ionizing radiation and redistributed ultraviolet radiation for two illustrative evolving Mars atmospheres whose initial surface pressures were 1 bar. We discuss the frequency with which redistributed ultraviolet flux from parent star flares exceeds the parent star ultraviolet flux at the planetary surface. We find that the redistributed ultraviolet from parent star flares is probably a fairly rare intermittent event for habitable zone planets orbiting solar-type stars except when they are young, but should completely dominate the direct steady ultraviolet radiation from the parent star for planets orbiting all stars less massive than about 0.5 solar masses. Our results suggest that coding organisms on such planets (and on the early Earth) may evolve very differently than on contemporary Earth, with diversity and evolutionary rate controlled by a stochastically varying mutation rate and frequent hypermutation episodes.

West Europe Report

DTIC Science & Technology

1987-03-23

Eurico de Melo STATE AND INTERNAL ADMINISTRATION 82,90/0 ACTIONS 39 26 13 12 3 Leonardo Ribeiro de Almeida NATIONAL DEFENSE 7.4,4...reported at the time, Sottomayor Cardia and Manuel Alegre were the principal proponents of immediate collaboration with the PRD [Democratic Renewal...particular Manuel Vallespin and Prudencia Pedrosa, undertook measures designed to provide support for drug-addicted soldiers. Suicides which were never

Partial rootzone drying (PRD) and regulated deficit irrigation (RDI) effects on stomal conductance, growth, photosynthetic capacity, and water-use efficiency of papaya

USDA-ARS?s Scientific Manuscript database

Papaya (Carica papaya, L.) is an important economic crop in tropical and subtropical countries in addition to its human health benefits. Papaya is a giant herbaceous species and maintaining adequate tissue turgidity and water availability is necessary to maintain the rigidity of the stem as well as...

Bacteriophage adsorption during transport through porous media: Chemical perturbations and reversibility

USGS Publications Warehouse

Bales, R.C.; Hinkle, S.R.; Kroeger, T.W.; Stocking, K.; Gerba, C.P.

1991-01-01

In a series of seven column experiments, attachment of the bacteriophage PRD-1 and MS-2 to silica beads at pH's 5.0-5.5 was at least partially reversible; however, release of attached phage was slow and breakthrough curves exhibited significant tailing. Rate coefficients for attachment and detachment were on the order of 10-4 and 10-6-10-4 s-1, respectively. Corresponding time scales were hours for attachment and days for detachment. The sticking efficiency (??) for phage attachment was near 0.01. The rate of phage release was enhanced by raising pH and introducing surface-active chemical species, illustrating the importance of chemical perturbations in promoting biocolloid transport. In a series of batch experiments, MS-2 adsorbed strongly to a hydrophobic surface, octadecyltrichlorosilane-bonded silica, at both pH's 5 and 7. Adsorption to the unbonded silica at pH 5 was linear, but was 2.5 (with Ca2+) to 0.25% (without Ca2+) of that to the bonded surface. Neither MS-2 nor PRD-1 adsorbed to unbonded silica at pH 7. Hydrophobic effects appear to be important for adsorption of even relatively hydrophilic biocolloids. ?? 1991 American Chemical Society.

[Periodontal disease in pediatric rheumatic diseases].

PubMed

Fabri, Gisele M C; Savioli, Cynthia; Siqueira, José T; Campos, Lucia M; Bonfá, Eloisa; Silva, Clovis A

2014-01-01

Gingivitis and periodontitis are immunoinflammatory periodontal diseases characterized by chronic localized infections usually associated with insidious inflammation This narrative review discusses periodontal diseases and mechanisms influencing the immune response and autoimmunity in pediatric rheumatic diseases (PRD), particularly juvenile idiopathic arthritis (JIA), childhood-onset systemic lupus erythematosus (C-SLE) and juvenile dermatomyositis (JDM). Gingivitis was more frequently observed in these diseases compared to health controls, whereas periodontitis was a rare finding. In JIA patients, gingivitis and periodontitis were related to mechanical factors, chronic arthritis with functional disability, dysregulation of the immunoinflammatory response, diet and drugs, mainly corticosteroids and cyclosporine. In C-SLE, gingivitis was associated with longer disease period, high doses of corticosteroids, B-cell hyperactivation and immunoglobulin G elevation. There are scarce data on periodontal diseases in JDM population, and a unique gingival pattern, characterized by gingival erythema, capillary dilation and bush-loop formation, was observed in active patients. In conclusion, gingivitis was the most common periodontal disease in PRD. The observed association with disease activity reinforces the need for future studies to determine if resolution of this complication will influence disease course or severity. Copyright © 2014 Elsevier Editora Ltda. All rights reserved.

Assessing a cross-border logistics policy using a performance measurement system framework: the case of Hong Kong and the Pearl River Delta region

NASA Astrophysics Data System (ADS)

Wong, David W. C.; Choy, K. L.; Chow, Harry K. H.; Lin, Canhong

2014-06-01

For the most rapidly growing economic entity in the world, China, a new logistics operation called the indirect cross-border supply chain model has recently emerged. The primary idea of this model is to reduce logistics costs by storing goods at a bonded warehouse with low storage cost in certain Chinese regions, such as the Pearl River Delta (PRD). This research proposes a performance measurement system (PMS) framework to assess the direct and indirect cross-border supply chain models. The PMS covers four categories including cost, time, quality and flexibility in the assessment of the performance of direct and indirect models. Furthermore, a survey was conducted to investigate the logistics performance of third party logistics (3PLs) at the PRD regions, including Guangzhou, Shenzhen and Hong Kong. The significance of the proposed PMS framework allows 3PLs accurately pinpoint the weakness and strengths of it current operations policy at four major performance measurement categories. Hence, this helps 3PLs further enhance the competitiveness and operations efficiency through better resources allocation at the area of warehousing and transportation.

Improving Remote Health Monitoring: A Low-Complexity ECG Compression Approach

PubMed Central

Al-Ali, Abdulla; Mohamed, Amr; Ward, Rabab

2018-01-01

Recent advances in mobile technology have created a shift towards using battery-driven devices in remote monitoring settings and smart homes. Clinicians are carrying out diagnostic and screening procedures based on the electrocardiogram (ECG) signals collected remotely for outpatients who need continuous monitoring. High-speed transmission and analysis of large recorded ECG signals are essential, especially with the increased use of battery-powered devices. Exploring low-power alternative compression methodologies that have high efficiency and that enable ECG signal collection, transmission, and analysis in a smart home or remote location is required. Compression algorithms based on adaptive linear predictors and decimation by a factor B/K are evaluated based on compression ratio (CR), percentage root-mean-square difference (PRD), and heartbeat detection accuracy of the reconstructed ECG signal. With two databases (153 subjects), the new algorithm demonstrates the highest compression performance (CR=6 and PRD=1.88) and overall detection accuracy (99.90% sensitivity, 99.56% positive predictivity) over both databases. The proposed algorithm presents an advantage for the real-time transmission of ECG signals using a faster and more efficient method, which meets the growing demand for more efficient remote health monitoring. PMID:29337892

Modeling removal of bacteriophages MS2 and PRD1 by dune recharge at Castricum, Netherlands

NASA Astrophysics Data System (ADS)

Schijven, Jack F.; Hoogenboezem, Wim; Hassanizadeh, S. Majid; Peters, Jos H.

1999-04-01

Removal of model viruses by dune recharge was studied at a field site in the dune area of Castricum, Netherlands. Recharge water was dosed with bacteriophages MS2 and PRD1 for 11 days at a constant concentration in a 10- by 15-m compartment that was isolated in a recharge basin. Breakthrough was monitored for 120 days at six wells with their screens along a flow line. Concentrations of both phages were reduced about 3 log10 within the first 2.4 m and another 5 log10 in a linear fashion within the following 27 m. A model accounting for one-site kinetic attachment as well as first-order inactivation was employed to simulate the bacteriophage breakthrough curves. The major removal process was found to be attachment of the bacteriophages. Detachment was very slow. After passage of the pulse of dosed bacteriophages, there was a long tail whose slope corresponds to the inactivation rate coefficient of 0.07-0.09 day-1 for attached bacteriophages. The end of the rising and the start of the declining limbs of the breakthrough curves could not be simulated completely, probably because of an as yet unknown process.

Phthalate esters in water and surface sediments of the Pearl River Estuary: distribution, ecological, and human health risks.

PubMed

Li, Xiaohui; Yin, Pinghe; Zhao, Ling

2016-10-01

The Pearl River Estuary (PRE) is vulnerable due to the increasingly serious environmental pollution, such as phthalate esters (PAEs) contaminants, from the Pearl River Delta (PRD). The concentrations of six US Environmental Protection Agency (USEPA) priority PAEs in water and surface sediments collected from the PRD's six main estuaries in spring, summer, and winter 2013 were measured by GC-MS. Total PAEs (∑6PAEs) concentrations were from 0.5 to 28.1 μg/L and from 0.88 to 13.6 μg/g (dry weight (DW)) in water and surface sediments, respectively. The highest concentration was detected in summer. Higher concentrations of PAEs were found in Yamen (YM) and Humen (HM) areas than the other areas. Bis(2-ethylhexyl)phthalate (DEHP) and dibutyl phthalate (DBP) were the dominant PAEs in the investigated areas, contributing between 61 and 95 % of the PAEs in water and from 85 to 98 % in surface sediments. Based on risk quotients (RQs), DEHP posed greater ecological risks to the studied aquatic environments than other measured compounds. Little human health risk from the target PAEs was identified.

Muslim Americans' safety and well-being in the wake of Trump: A public health and social justice crisis.

PubMed

Abu-Ras, Wahiba; Suárez, Zulema E; Abu-Bader, Soleman

2018-04-09

This study examined the perceived impact of religious discrimination and Islamophobia on Muslim Americans' well-being during the 2016 United States presidential election campaign. Data were collected from a national sample of 1,130 Muslim Americans. Perceived religious discrimination (PRD) was measured using the Perceived Religious Discrimination Scale. Results of canonical correlation analysis showed that perceived Islamophobia was associated with safety (β = .45, p < .001), level of stress (β = -.25, p < .001), level of religiosity (β = -.11, p < .05), and employment (β = .11, p < .05). PRD was associated with preexposure to religious-based discrimination; β = -.12, p < .05), safety (.47, p < .001), level of stress (β = -.33, p < .001), religiosity (β = -.15, p < .010), and years in the United States (β = .16, p < .010). Results also suggest that some Muslim subgroups, such as women and older people, may face "double jeopardy" based on multiple stigmatized identities. When addressing mental health concerns in marginalized groups, it is necessary to link health with social justice and examine how social injustices may affect people's well-being. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Improving Remote Health Monitoring: A Low-Complexity ECG Compression Approach.

PubMed

Elgendi, Mohamed; Al-Ali, Abdulla; Mohamed, Amr; Ward, Rabab

2018-01-16

Recent advances in mobile technology have created a shift towards using battery-driven devices in remote monitoring settings and smart homes. Clinicians are carrying out diagnostic and screening procedures based on the electrocardiogram (ECG) signals collected remotely for outpatients who need continuous monitoring. High-speed transmission and analysis of large recorded ECG signals are essential, especially with the increased use of battery-powered devices. Exploring low-power alternative compression methodologies that have high efficiency and that enable ECG signal collection, transmission, and analysis in a smart home or remote location is required. Compression algorithms based on adaptive linear predictors and decimation by a factor B / K are evaluated based on compression ratio (CR), percentage root-mean-square difference (PRD), and heartbeat detection accuracy of the reconstructed ECG signal. With two databases (153 subjects), the new algorithm demonstrates the highest compression performance ( CR = 6 and PRD = 1.88 ) and overall detection accuracy (99.90% sensitivity, 99.56% positive predictivity) over both databases. The proposed algorithm presents an advantage for the real-time transmission of ECG signals using a faster and more efficient method, which meets the growing demand for more efficient remote health monitoring.

Environmental factors influencing the distribution of total and fecal coliform bacteria in six water storage reservoirs in the Pearl River Delta Region, China.

PubMed

Hong, Huachang; Qiu, Jianwen; Liang, Yan

2010-01-01

The Pearl River Delta (PRD) is one of the most developed and densely populated regions in China. Quantifying the amount of pathogens in the source of drinking water is important for improving water quality. We collected water samples from six major water storage reservoirs in the PRD region in both wet and dry seasons in 2006. Results showed that external environmental factors, such as precipitation, location, as well as the internal environmental factors, i.e., physicochemical properties of the water, were closely related with the distribution of coliforms. Seasonally, the coliform bacterial concentrations in wet season were one to two orders of magnitude greater than those in dry season. Spatially, coliform bacterial levels in reservoirs near urban and industrial areas were significantly higher (p < 0.05) than those in remote areas. Correlation analyses showed that the levels of coliforms had close relationships with pH, temperature, suspended solid, organic and inorganic nutrients in water. Principal components analysis further demonstrated that total coliforms in the reservoirs were closely related with water physicochemical properties, while fecal coliforms were more associated with external input brought in by seasonal runoff.

Influence of changes in hydrodynamic conditions on cadmium transport in tidal river network of the Pearl River Delta, China.

PubMed

Dou, Ming; Zuo, Qiting; Zhang, Jinping; Li, Congying; Li, Guiqiu

2013-09-01

With rapid economic development, the Pearl River Delta (PRD) of China has experienced a series of serious heavy metal pollution events. Considering complex hydrodynamic and pollutants transport process, one-dimensional hydrodynamic model and heavy metal transport model were developed for tidal river network of the PRD. Then, several pollution emergency scenarios were designed by combining with the upper inflow, water quality and the lower tide level boundary conditions. Using this set of models, the temporal and spatial change process of cadmium (Cd) concentration was simulated. The influence of change in hydrodynamic conditions on Cd transport in tidal river network was assessed, and its transport laws were summarized. The result showed the following: Flow changes in the tidal river network were influenced remarkably by tidal backwater action, which further influenced the transport process of heavy metals; Cd concentrations in most sections while encountering high tide were far greater than those while encountering middle or low tides; and increased inflows from upper reaches could intensify water pollution in the West River (while encountering high tide) or the North River (while encountering middle or low tides).

[Functional and Anatomic Outcomes of Primary and Secondary Internal Limiting Membrane Transplantation in Large and Persistent Macular Holes].

PubMed

Hess, Jelka A; Michels, Stephan; Becker, Matthias D

2017-11-20

Background The gold standard therapy for full-thickness macular holes (FTMH) is vitrectomy (PPV) with peeling of the internal limiting membrane (ILM), gas tamponade of the vitreous cavity and postoperative face-down positioning. Nevertheless, eyes with large macular holes (> 400 µm) and surgical failures remain difficult to manage. Recently, ILM transplantation (ILM-TX) techniques were developed with acceptable results, advocating different mechanisms of hole closure: in such a setting, the ILM could serve as a scaffold for neuronal tissue in the pedicle ILM flap technique or the ILM could induce a contraction of the FTMH rims through shrinking of a folded ILM plug. Patients/Material and Methods This retrospective study evaluates the functional and anatomic outcomes following ILM-TX for large FTMH and failed FMTH surgery. Large holes (group 1) were treated by the pedicle flap and the plug technique. Persistent holes following vitrectomy and ILM peeling (group 2) were treated with the plug technique. All ILM-TX were performed under perfluorocarbon liquid (PFCL) with a subsequent silicone oil tamponade. Results In group 1 (6 eyes), three eyes had a free ILM graft and three eyes underwent a pedunculated ILM-TX. The mean best corrected visual acuity (BCVA, LogMar) before primary ILM-TX was 1.18 ± 0.54 with a mean initial hole size of 681 ± 106 µm and a photoreceptor defect (PRD) of 1829 ± 474 µm. Five of six eyes showed a postoperative anatomical macular hole closure (83%). The mean BCVA after a mean follow-up of 9.3 ± 5.1 months was 0.83 ± 0.31 after a free ILM graft and 0.95 ± 0.79 after a pedunculated ILM flap. The PRD reduced to 1781 ± 713 µm after a free ILM graft and 1148 ± 378 µm after a pedunculated ILM flap. In group 2 (7 eyes), all patients had failed initial macular hole surgery closure. Prior to free ILM-TX BCVA was 1.05 ± 0.41, the hole size was 433 ± 183 µm and PRD was 2012 ± 718 µm. After a mean of 9.6 ± 4.1 months following ILM-TX, in six of seven eyes the FTMH hole was closed (86%), BCVA improved to 0.53 ± 0.34 and the PRD shortened to 843 ± 291 µm. Conclusion In most cases, with large FTMH or holes after failed vitrectomy plus ILM peeling, ILM-TX allows a hole closure. Functional outcomes show stabilization and sometimes even a slight improvement. Georg Thieme Verlag KG Stuttgart · New York.

Energetic particles in spherical tokamak plasmas

DOE PAGES

McClements, K. G.; Fredrickson, E. D.

2017-03-21

Spherical tokamaks (STs) typically have lower magnetic fields than conventional tokamaks, but similar mass densities. Suprathermal ions with relatively modest energies, in particular beam-injected ions, consequently have speeds close to or exceeding the Alfvén velocity, and can therefore excite a range of Alfvénic instabilities which could be driven by (and affect the behaviour of) fusion α-particles in a burning plasma. STs heated with neutral beams, including the small tight aspect ratio tokamak (START), the mega amp spherical tokamak (MAST), the national spherical torus experiment (NSTX) and Globus-M, have thus provided an opportunity to study toroidal Alfvén eigenmodes (TAEs), together withmore » higher frequency global Alfvén eigenmodes (GAEs) and compressional Alfvén eigenmodes (CAEs), which could affect beam current drive and channel fast ion energy into bulk ions in future devices. In NSTX GAEs were correlated with a degradation of core electron energy confinement. In MAST pulses with reduced magnetic field, CAEs were excited across a wide range of frequencies, extending to the ion cyclotron range, but were suppressed when hydrogen was introduced to the deuterium plasma, apparently due to mode conversion at ion–ion hybrid resonances. At lower frequencies fishbone instabilities caused fast particle redistribution in some MAST and NSTX pulses, but this could be avoided by moving the neutral beam line away from the magnetic axis or by operating the plasma at either high density or elevated safety factor. Fast ion redistribution has been observed during GAE avalanches on NSTX, while in both NSTX and MAST fast ions were transported by saturated kink modes, sawtooth crashes, resonant magnetic perturbations and TAEs. The energy dependence of fast ion redistribution due to both sawteeth and TAEs has been studied in Globus-M. High energy charged fusion products are unconfined in present-day STs, but have been shown in MAST to provide a useful diagnostic of beam ion behaviour, supplementing the information provided by neutron detectors. In MAST electrons were accelerated to highly suprathermal energies as a result of edge localised modes, while in both MAST and NSTX ions were accelerated due to internal reconnection events. Lastly, ion acceleration has also been observed during merging-compression start-up in MAST.« less

Polar motion excitation analysis due to global continental water redistribution

NASA Astrophysics Data System (ADS)

Fernandez, L.; Schuh, H.

2006-10-01

We present the results obtained when studying the hydrological excitation of the Earth‘s wobble due to global redistribution of continental water storage. This work was performed in two steps. First, we computed the hydrological angular momentum (HAM) time series based on the global hydrological model LaD (Land Dynamics model) for the period 1980 till 2004. Then, we compared the effectiveness of this excitation by analysing the residuals of the geodetic time series after removing atmospheric and oceanic contributions with the respective hydrological ones. The emphasis was put on low frequency variations. We also present a comparison of HAM time series from LaD with respect to that one from a global model based on the assimilated soil moisture and snow accumulation data from NCEP/NCAR (The National Center for Environmental Prediction/The National Center for Atmospheric Research) reanalysis. Finally, we evaluate the performance of LaD model in closing the polar motion budget at seasonal periods in comparison with the NCEP and the Land Data Assimilation System (LDAS) models.

The Statistical Sobolev-Rosseland Mean and the Effects of Frequency Redistribution on Wolf-Rayet Wind Driving

NASA Astrophysics Data System (ADS)

Onifer, A. J.; Gayley, K. G.

2003-06-01

The optically thick character of Wolf-Rayet winds implies that stellar continuum photons are multiply scattered, as a result of both free electron opacity and overlapping wind-broadened spectral lines. This allows the wind to accumulate a substantial excess in momentum flux relative to the driving radiation field, as is observationally required. Nevertheless, sustaining such a high degree of multiple scattering requires not only a large optical depth spatially but also substantial spectral blanketing. The latter is difficult to maintain when redistribution during scattering allows radiative flux to shift preferentially into spectral regions with fewer lines, since then the channels carrying much of the flux are also the least well blanketed. This paper parameterizes the potential severity of this effect in simple terms, using a generalization of the Rosseland mean treated in the Sobolev approximation. We show that our approach provides an informative starting point for characterizing and conceptualizing nongray effects in optically thick supersonic flows.

Transcranial cavitation-mediated ultrasound therapy at sub-MHz frequency via temporal interference modulation

NASA Astrophysics Data System (ADS)

Sun, Tao; Sutton, Jonathan T.; Power, Chanikarn; Zhang, Yongzhi; Miller, Eric L.; McDannold, Nathan J.

2017-10-01

Sub-megahertz transmission is not usually adopted in pre-clinical small animal experiments for focused ultrasound (FUS) brain therapy due to the large focal size. However, low frequency FUS is vital for preclinical evaluations due to the frequency-dependence of cavitation behavior. To maximize clinical relevance, a dual-aperture FUS system was designed for low-frequency (274.3 kHz) cavitation-mediated FUS therapy. Combining two spherically curved transducers provides significantly improved focusing in the axial direction while yielding an interference pattern with strong side lobes, leading to inhomogeneously distributed cavitation activities. By operating the two transducers at slightly offset frequencies to modulate this interference pattern over the period of sonication, the acoustic energy was redistributed and resulted in a spatially homogenous treatment profile. Simulation and pressure field measurements in water were performed to assess the beam profiles. In addition, the system performance was demonstrated in vivo in rats via drug delivery through microbubble-mediated blood-brain barrier disruption. This design resulted in a homogenous treatment profile that was fully contained within the rat brain at a clinically relevant acoustic frequency.

Elution of viruses by ionic and nonionic surfactants.

PubMed Central

Fujito, B T; Lytle, C D

1996-01-01

The ionic and nonionic surfactants sodium dodecyl sulfate and Triton X-100, respectively, eluted two viruses, phi X174 and PRD1, which were adsorbed to the ionic and nonionic binding membranes cationic polysulfone and nitrocellulose, respectively. Results indicated that complete elution was readily achieved only when combinations of surfactants and binding membranes were matched (i.e., ionic-ionic or nonionic-nonionic). PMID:8795240

West Europe Report

DTIC Science & Technology

1987-05-26

Assurance Displayed, by Antonio Pinto Leite 42 Victory Over PRD 43 Briefs Madeira-South Africa Cooperation in Health 45 TURKEY Prime Minister Ozal’s...Personalities, Activities, by Jean Qoaquen 82 Corbeville Central Laboratory 92 PORTUGAL Virgilio de Carvalho; DIARIO DE NOTICIAS, 14 Apr 87...Green Party), as well as a few notoriously critical party colleagues, among whom Wim Meijer, Jacques Wallage, Hedy d’Ancona and Hans Kombrink. It

Assessment of regional air quality resulting from emission control in the Pearl River Delta region, southern China.

PubMed

Wang, N; Lyu, X P; Deng, X J; Guo, H; Deng, T; Li, Y; Yin, C Q; Li, F; Wang, S Q

2016-12-15

To evaluate the impact of emission control measures on the air quality in the Pearl River Delta (PRD) region of South China, statistic data including atmospheric observations, emissions and energy consumptions during 2006-2014 were analyzed, and a Weather Research and Forecasting - Community Multi-scale Air Quality (WRF-CMAQ) model was used for various scenario simulations. Although energy consumption doubled from 2004 to 2014 and vehicle number significantly increased from 2006 to 2014, ambient SO 2 , NO 2 and PM 10 were reduced by 66%, 20% and 24%, respectively, mainly due to emissions control efforts. In contrast, O 3 increased by 19%. Model simulations of three emission control scenarios, including a baseline (a case in 2010), a CAP (a case in 2020 assuming control strength followed past control tendency) and a REF (a case in 2020 referring to the strict control measures based on recent policy/plans) were conducted to investigate the variations of air pollutants to the changes in NO x , VOCs and NH 3 emissions. Although the area mean concentrations of NO x , nitrate and PM 2.5 decreased under both NO x CAP (reduced by 1.8%, 0.7% and 0.2%, respectively) and NO x REF (reduced by 7.2%, 1.8% and 0.3%, respectively), a rising of PM 2.5 was found in certain areas as reducing NO x emissions elevated the atmospheric oxidizability. Furthermore, scenarios with NH 3 emission reductions showed that nitrate was sensitive to NH 3 emissions, with decreasing percentages of 0-10.6% and 0-48% under CAP and REF, respectively. Controlling emissions of VOCs reduced PM 2.5 in the southwestern PRD where severe photochemical pollution frequently occurred. It was also found that O 3 formation in PRD was generally VOCs-limited while turned to be NO x -limited in the afternoon (13:00-17:00), suggesting that cutting VOCs emissions would reduce the overall O 3 concentrations while mitigating NO x emissions in the afternoon could reduce the peak O 3 levels. Copyright © 2016 Elsevier B.V. All rights reserved.

High resolution of anthropogenic atmospheric emissions of 12 heavy metals in the three biggest metropolitan areas, China

NASA Astrophysics Data System (ADS)

Tian, H.; Zhu, C.

2015-12-01

Atmospheric emissions of typical toxic heavy metals from anthropogenic sources have received worldwide concerns due to their adverse effects on human health and the ecosystem. An integrated inventory of anthropogenic emissions of twelve HMs (Hg, As, Se, Pb, Cd, Cr, Ni, Sb, Mn, Co, Cu and Zn) in the three biggest metropolitan areas, including Beijing-Tianjin-Hebei (BTH) region, Yangtze River Delta (YRD) region and Pearl River Delta (PRD) region, are developed for 1980-2012 by combining with detailed activity data and inter-annual dynamic emission factors which are determined by S-shaped curves on account of technology progress, economic development, and emission control. The results indicate total emissions of twelve HMs in the three metropolitan regions have increased from 5448.8 tons in 1980 to 19054.9 tons in 2012, with an annual average growth rate of about 4.0%. Due to significant difference in industrial structures and energy consumption compositions, remarkable distinctions can be observed with respect to source contributions of total HM emissions from above three metropolitan areas. Specifically, the ferrous metal smelting sector, coal combustion by industrial boilers and coal combustion by power plants are found to be the primary source of total HM emissions in the BTH region (about 34.2%), YRD region (about 28.2%) and PRD region (about 24.3%), respectively. Furthermore, we allocate the annual emissions of these heavy metals in 2012 at a high spatial resolution of 9 km × 9 km grid with ArcGIS methodology and surrogate indexes, such as regional population and gross domestic product (GDP). The peak of HM emissions are mainly distributed over the grid cells of Beijing, Tianjin, Tangshan, Shijiazhuang, Handan and Baoding in the BTH region; Shanghai, Suzhou, Wuxi, Nanjing, Hangzhou, Ningbo in the YRD region; Guangzhou, Shenzhen, Dongguan, Foshan in the PYD region, respectively. Additionally, monthly emission profiles are established in order to further identify the temporal emission characteristics of HMs. Key words: heavy metals (HMs), emission inventory, time-varying dynamic emission factor, temporal and spatial characteristics, Beijing-Tianjin-Hebei (BTH) region, Yangtze River Delta (YRD) region, Pearl River Delta (PRD) region, China

Photochemically consumed hydrocarbons and their relationship with ozone formation in two megacities of China

NASA Astrophysics Data System (ADS)

Chang, C.; Wang, J.; Liu, S.; Shao, M.; Zhang, Y.; Zhu, T.; Shiu, C.; Lai, C.

2010-12-01

Two on-site continuous measurements of ozone and its precursors in two megacities of China were carried out in an urban site of Beijing and a suburban site near Guangzhou in the Pearl River Delta (PRD) to estimate precursor consumption and to assess its relationship with oxidant (O3+NO2) formation level. An observation-based method (OBM) with the precursor consumption concept was adopted to assess the relationship between oxidant production and amounts of photochemically consumed non-methane hydrocarbons (NMHCs). In this approach, the ratio of ethylbenzene to m,p-xylenes was used to estimate the degree of photochemical processing, as well as the amounts of photochemically consumed NMHCs by reacting with OH. By trying to correlate the observed oxidant with the observed NMHC concentration, the two areas both revealed nearly no to low correlation between them. However, it existed fair to good correlations (R2=0.68 for Beijing, 0.53 for PRD) between the observed oxidant level and the degree of photochemical processing (ethylbenzene/m,p-xylenes). Furthermore, after taking the approach of consumption to estimate the consumed amounts of NMHCs, an interesting finding reveals that the definite correlation existed between the observed oxidant level and the total consumed NMHCs. The good correlations (R2=0.83 for Beijing, 0.81 for PRD) implies that the ambient oxidant level correlated to the amount of consumed NMHCs. The results of the two megacities in China by using the OBM with the precursor consumption concept can provide another pathway to explore the relationship between photochemically produced oxidant and consumed precursors, and will be helpful to validate model results and to reduce uncertainty of model predictions. However, the method has some room for uncertainty, as injection of fresh precursor emissions and additional boundary ozone involved, etc. could affect the estimation of consumed NMHCs and observed oxidant levels. Assistance of approaches in assessing the influence of the interfering factors would be helpful to acquire more reliable inferences of relationship between oxidant formation and precursor consumption.

The annual cost of not breastfeeding in Indonesia: the economic burden of treating diarrhea and respiratory disease among children (< 24mo) due to not breastfeeding according to recommendation.

PubMed

Siregar, Adiatma Y M; Pitriyan, Pipit; Walters, Dylan

2018-01-01

In Indonesia, 96% of children (< 24mo) are breastfed. However, only 42% of children (< 6mo) are exclusively breastfed, as per World Health Organization recommendations. Breastfeeding provides protective benefits such as reducing the risk of morbidity and mortality associated with diarrhea and pneumonia/respiratory disease (PRD). This study estimates the potential economic impact of not breastfeeding according to recommendation in Indonesia based on infants suffering from attributable diarrhea and PRD. A cost analysis examined both the healthcare system costs and non-medical costs for children (< 24mo) with diarrhea and PRD. Data collection took place between 2015 and 2016 and healthcare expenditures were assessed in 13 facilities, in five sites including Bandung and Tomohon City. Costs from a provider perspective were estimated using healthcare records and 26 interviews with healthcare workers. A discount rate of 3% was used. A cross-sectional survey with caregiver-child pairs ( n  = 615) collected data related to out of pocket costs such transportation and opportunity costs such as wage loss. These figures were combined with the national disease prevalence rates from Indonesia Demographic and Health Survey 2012, and the relative risk of disease of not breastfeeding according to recommendation from literatures to extrapolate the financial burden of treatment. The healthcare system cost due to not breastfeeding according to recommendation was estimated at US$118 million annually. The mean healthcare system cost and out of pocket costs was US$11.37 and US$3.85 respectively. This cost consists of US$88.64 million of provider costs and US$29.98 million of non-medical patient costs. The cost of not breastfeeding according to recommendation is potentially high, therefore the Indonesian government needs to invest in breastfeeding protection, promotion and support as the potential healthcare system cost savings are significant. As suggested by other studies, the long term cost due to cognitive losses of providing not breastfeeding according to recommendation should also be taken into account to provide a complete understanding of the economic impact of not breastfeeding according to recommendation.

Competition of coagulation sink and source rate: New particle formation in the Pearl River Delta of China

NASA Astrophysics Data System (ADS)

Gong, Youguo; Hu, Min; Cheng, Yafang; Su, Hang; Yue, Dingli; Liu, Feng; Wiedensohler, A.; Wang, Zhibin; Kalesse, H.; Liu, Shang; Wu, Zhijun; Xiao, Kaitao; Mi, Puchun; Zhang, Yuanhang

The coagulation sink and its role in new particle formation are investigated based on data obtained during the PRIDE-PRD2004 campaign at Xinken of Pearl River Delta, China. Analysis of size distributions and mode contributions of the coagulation sink show that the observed higher load of accumulation mode particles impose a significant effect on the coagulation sink and result in higher coagulation sinks at Xinken despite of the lower total particle number compared with other areas. Hence it is concluded that the higher coagulation sink may depress the occurrence frequency of new particle formation events. The strategies targeting at controlling accumulation mode particles may have influences on the frequency of new particle formation events at this area. The factors affecting the coagulation sink are evaluated. The relatively lower ambient relative humidities may weaken the coagulation sink and facilitate the occurrence of new particle formation events during noontime, while the surmise of nucleation and growth involving organic matter may imply an actually higher coagulation sink than expected. These factors have a significant influence on the ultimate fate of the newly formed nuclei and new particle formation. A comparison of event and non-event days indicates that the coagulation sink is not the only decisive factor affecting new particle formation, other factors including the precursor vapors and photochemical activity are none the less important either. Competition of coagulation sink and high source rate leads to the occurrence of new particle formation events at Xinken.

Wealth redistribution in our small world

NASA Astrophysics Data System (ADS)

Iglesias, J. R.; Gonçalves, S.; Pianegonda, S.; Vega, J. L.; Abramson, G.

2003-09-01

We present a simplified model for the exploitation of resources by interacting agents, in an economy with small-world properties. It is shown that Gaussian distributions of wealth, with some cutoff at a poverty line are present for all values of the parameters, while the frequency of maxima and minima strongly depends on the connectivity and the disorder of the lattice. Finally, we compare a system where the commercial links are frozen with an economy where agents can choose their commercial partners at each time step.

Income Redistribution Predicts Greater Life Satisfaction Across Individual, National, and Cultural Characteristics.

PubMed

Cheung, Felix

2017-08-03

The widening income gap between the rich and the poor has important social implications. Governmental-level income redistribution through tax and welfare policies presents an opportunity to reduce income inequality and its negative consequences. The current longitudinal studies examined whether within-region changes in income redistribution over time relate to life satisfaction. Moreover, I examined potential moderators of this relationship to test the strong versus weak hypotheses of income redistribution. The strong hypothesis posits that income redistribution is beneficial to most. The weak hypothesis posits that income redistribution is beneficial to some and damaging to others. Using a nationally representative sample of 57,932 German respondents from 16 German states across 30 years (Study 1) and a sample of 112,876 respondents from 33 countries across 24 years (Study 2), I found that within-state and within-nation changes in income redistribution over time were associated with life satisfaction. The models predicted that a 10% reduction in Gini through income redistribution in Germany increased life satisfaction to the same extent as an 37% increase in annual income (Study 1), and a 5% reduction in Gini through income redistribution increased life satisfaction to the same extent as a 11% increase in GDP (Study 2). These associations were positive across individual, national, and cultural characteristics. Increases in income redistribution predicted greater satisfaction for tax-payers and welfare-receivers, for liberals and conservatives, and for the poor and the rich. These findings support the strong hypothesis of income redistribution and suggest that redistribution policies may play an important role in societal well-being. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

47 CFR 73.9001 - Redistribution control of digital television broadcasts.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 4 2010-10-01 2010-10-01 false Redistribution control of digital television... RADIO SERVICES RADIO BROADCAST SERVICES Digital Broadcast Television Redistribution Control § 73.9001 Redistribution control of digital television broadcasts. Licensees of TV broadcast stations may utilize the...

Reversible Inactivation and Desiccation Tolerance of Silicified Viruses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Laidler, James J.; Shugart, Jessica A.; Cady, Sherry L.

2013-11-19

Long-distance host-independent virus dispersal is poorly understood, especially for viruses found in isolated ecosystems. To demonstrate a possible dispersal mechanism, we show that bacteriophage T4, archaeal virus SSV-K and Vaccinia are reversibly inactivated by mineralization in silica under conditions similar to volcanic hot springs. By contrast, bacteriophage PRD1 is not silicified. Moreover silicification provides viruses with remarkable desiccation resistance, which could allow extensive aerial dispersal.

Tangential-flow ultrafiltration with integrated inhibition detection for recovery of surrogates and human pathogens from large-volume source water and finished drinking water.

PubMed

Gibson, Kristen E; Schwab, Kellogg J

2011-01-01

Tangential-flow ultrafiltration was optimized for the recovery of Escherichia coli, Enterococcus faecalis, Clostridium perfringens spores, bacteriophages MS2 and PRD1, murine norovirus, and poliovirus seeded into 100-liter surface water (SW) and drinking water (DW) samples. SW and DW collected from two drinking water treatment plants were then evaluated for human enteric viruses.

Materials Research in Support of Superconducting Machinery - II

DTIC Science & Technology

1974-10-01

iwiRnai«.|UiipWiw .mm i MARTIN MARIETTA AEROSPACE, DENVER DIVISION Study of Fracture Behavior of Metals for Superconducting Applications...into design use by compiling and publishing what literature data are available and assessing what properties need further study . The first year’s...non-metal base composites, including B-epoxy, C-epoxy and polyimide, PRD 49-epoxy, borsic-Al, Steel-Al. Screening study of composites for torque

Action of hydrogen peroxide on degradation of DNA after irradiation in Escherichia coli.

PubMed

Keller, K M; Pollard, E C

1977-05-01

Hydrogen peroxide (H2O2), which produces breaks in cellular DNA, has not hitherto been shown to cause degradation of DNA. In this investigation it is shown that if transcription is blocked with rifampin, treatment with H2O2 causes degradation of DNA to nearly the same extent as does gamma-radiation. Further, if cells are given a treatment with H2O2 and incubated for 50 min, the amount of degradation in a second treatment is markedly less. This is attributed to the induction of the inhibitor of post-irradiation degradation of DNA (prd) by the first treatment. There is thus a double action of H2O2: first, to induce inhibition, and second, to cause degradation of DNA to begin in non-induced cells. The genetic dependence of induction by H2O2 mimics that of ionizing radiation. Accordingly, the induction process does not occur in recA- and lex- cells, because they are not inducible and is absent in recB- cells because they lack exonuclease V, the major component of prd. Potassium iodide (KI), an OH radical scavenger, negates the action of peroxide on DNA. The results obtained in this study suggest a possible theory for the evolution of radiation response systems

Source apportionment of ambient volatile organic compounds in the Pearl River Delta, China: Part II

NASA Astrophysics Data System (ADS)

Liu, Ying; Shao, Min; Lu, Sihua; Chang, Chih-Chung; Wang, Jia-Lin; Fu, Linlin

The chemical mass balance receptor model was applied to the source apportionment of 58 hydrocarbons measured at seven sites in a field campaign that examined regional air quality in the Pearl River Delta (PRD) region in the fall of 2004. A total of 12 volatile organic compound (VOC) emission sources were considered, including gasoline- and diesel-powered vehicle exhausts, headspace vapors of gasoline and diesel fuel, vehicle evaporative emissions, liquid petroleum gas (LPG) leakage, paint vapors, asphalt emissions from paved roads, biomass combustion, coal combustion, the chemical industry, and petroleum refineries. Vehicle exhaust was the largest source of VOCs, contributing to >50% of ambient VOCs at the three urban sites (Guangzhou, Foshan, and Zhongshan). LPG leakage played an important role, representing 8-16% of emissions at most sites in the PRD. Solvent usage was the biggest emitter of VOCs at Dongguan, an industrial site, contributing 33% of ambient VOCs. Similarly, at Xinken, a non-urban site, the evaporation of solvents and coatings was the largest emission source, accounting for 31% of emissions, probably because it was downwind of Dongguan. Local biomass combustion was a noticeable source of VOCs at Xinken; although its contribution was estimated at 14.3%, biomass combustion was the third largest VOC source at this site.

Reducing flicker noise in chemical vapor deposition graphene field-effect transistors

NASA Astrophysics Data System (ADS)

Arnold, Heather N.; Sangwan, Vinod K.; Schmucker, Scott W.; Cress, Cory D.; Luck, Kyle A.; Friedman, Adam L.; Robinson, Jeremy T.; Marks, Tobin J.; Hersam, Mark C.

2016-02-01

Single-layer graphene derived from chemical vapor deposition (CVD) holds promise for scalable radio frequency (RF) electronic applications. However, prevalent low-frequency flicker noise (1/f noise) in CVD graphene field-effect transistors is often up-converted to higher frequencies, thus limiting RF device performance. Here, we achieve an order of magnitude reduction in 1/f noise in field-effect transistors based on CVD graphene transferred onto silicon oxide substrates by utilizing a processing protocol that avoids aqueous chemistry after graphene transfer. Correspondingly, the normalized noise spectral density (10-7-10-8 μm2 Hz-1) and noise amplitude (4 × 10-8-10-7) in these devices are comparable to those of exfoliated and suspended graphene. We attribute the reduction in 1/f noise to a decrease in the contribution of fluctuations in the scattering cross-sections of carriers arising from dynamic redistribution of interfacial disorder.

13 CFR 309.2 - Redistributions under part 307.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Redistributions under part 307. 309.2 Section 309.2 Business Credit and Assistance ECONOMIC DEVELOPMENT ADMINISTRATION, DEPARTMENT OF COMMERCE REDISTRIBUTIONS OF INVESTMENT ASSISTANCE § 309.2 Redistributions under part 307. (a) A Recipient...

13 CFR 309.1 - Redistributions under parts 303, 305 and 306.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Redistributions under parts 303, 305 and 306. 309.1 Section 309.1 Business Credit and Assistance ECONOMIC DEVELOPMENT ADMINISTRATION, DEPARTMENT OF COMMERCE REDISTRIBUTIONS OF INVESTMENT ASSISTANCE § 309.1 Redistributions under parts 303, 305...

Survivability of Autonomous Microgrid during Overload Events

DOE Office of Scientific and Technical Information (OSTI.GOV)

Du, Wei; Lasseter, Robert H.; Khalsa, Amrit S.

Grid-forming sources are voltage sources that draw necessary currents to meet any load changes. A load step can cause part or all of these sources to become overloaded in a microgrid. This paper presents an overload mitigation controller that addresses the two overload issues in a microgrid by actively controlling the sources’ frequency. When part of the sources in a microgrid is overloaded, the controller autonomously transfers the extra load to other sources by rapidly reducing its frequency. The frequency difference between sources during transient results in a change of phase angle, which redistributes the power flow. When all sourcesmore » in a microgrid are overloaded, each source keeps dropping the frequency. Therefore, under frequency load shedding can be used to trip the non-critical loads resulting in the survival of microgrid. The advantages of these concepts are that communications between sources are not needed during transient, and the robust voltage control is maintained. Lastly, simulation and field tests from CERTS/AEP microgrid test site verify that the control strategy is effective in both purely inverter-based microgrids and inverter & generator mixed microgrids.« less

Survivability of Autonomous Microgrid during Overload Events

DOE PAGES

Du, Wei; Lasseter, Robert H.; Khalsa, Amrit S.

2018-04-23

Grid-forming sources are voltage sources that draw necessary currents to meet any load changes. A load step can cause part or all of these sources to become overloaded in a microgrid. This paper presents an overload mitigation controller that addresses the two overload issues in a microgrid by actively controlling the sources’ frequency. When part of the sources in a microgrid is overloaded, the controller autonomously transfers the extra load to other sources by rapidly reducing its frequency. The frequency difference between sources during transient results in a change of phase angle, which redistributes the power flow. When all sourcesmore » in a microgrid are overloaded, each source keeps dropping the frequency. Therefore, under frequency load shedding can be used to trip the non-critical loads resulting in the survival of microgrid. The advantages of these concepts are that communications between sources are not needed during transient, and the robust voltage control is maintained. Lastly, simulation and field tests from CERTS/AEP microgrid test site verify that the control strategy is effective in both purely inverter-based microgrids and inverter & generator mixed microgrids.« less

Automatic generation of efficient array redistribution routines for distributed memory multicomputers

NASA Technical Reports Server (NTRS)

Ramaswamy, Shankar; Banerjee, Prithviraj

1994-01-01

Appropriate data distribution has been found to be critical for obtaining good performance on Distributed Memory Multicomputers like the CM-5, Intel Paragon and IBM SP-1. It has also been found that some programs need to change their distributions during execution for better performance (redistribution). This work focuses on automatically generating efficient routines for redistribution. We present a new mathematical representation for regular distributions called PITFALLS and then discuss algorithms for redistribution based on this representation. One of the significant contributions of this work is being able to handle arbitrary source and target processor sets while performing redistribution. Another important contribution is the ability to handle an arbitrary number of dimensions for the array involved in the redistribution in a scalable manner. Our implementation of these techniques is based on an MPI-like communication library. The results presented show the low overheads for our redistribution algorithm as compared to naive runtime methods.

The redistributive effect of health care finance in twelve OECD countries.

PubMed

van Doorslaer, E; Wagstaff, A; van der Burg, H; Christiansen, T; Citoni, G; Di Biase, R; Gerdtham, U G; Gerfin, M; Gross, L; Häkinnen, U; John, J; Johnson, P; Klavus, J; Lachaud, C; Lauritsen, J; Leu, R; Nolan, B; Pereira, J; Propper, C; Puffer, F; Rochaix, L; Schellhorn, M; Sundberg, G; Winkelhake, O

1999-06-01

The OECD countries finance their health care through a mixture of taxes, social insurance contributions, private insurance premiums and out-of-pocket payments. The various payment sources have very different implications for both vertical and horizontal equity and on redistributive effect which is a function of both. This paper presents results on the income redistribution consequences of the health care financing mixes adopted in twelve OECD countries by decomposing the overall income redistributive effect into a progressivity, horizontal inequity and reranking component. The general finding of this study is that the vertical effect is much more important than horizontal inequity and reranking in determining the overall redistributive effect but that their relative importance varies by source of payment. Public finance sources tend to have small positive redistributive effects and less differential treatment while private financing sources generally have (larger) negative redistributive effects which are to a substantial degree caused by differential treatment.

Understanding re-distribution of road deposited particle-bound pollutants using a Bayesian Network (BN) approach.

PubMed

Liu, An; Wijesiri, Buddhi; Hong, Nian; Zhu, Panfeng; Egodawatta, Prasanna; Goonetilleke, Ashantha

2018-05-08

Road deposited pollutants (build-up) are continuously re-distributed by external factors such as traffic and wind turbulence, influencing stormwater runoff quality. However, current stormwater quality modelling approaches do not account for the re-distribution of pollutants. This undermines the accuracy of stormwater quality predictions, constraining the design of effective stormwater treatment measures. This study, using over 1000 data points, developed a Bayesian Network modelling approach to investigate the re-distribution of pollutant build-up on urban road surfaces. BTEX, which are a group of highly toxic pollutants, was the case study pollutants. Build-up sampling was undertaken in Shenzhen, China, using a dry and wet vacuuming method. The research outcomes confirmed that the vehicle type and particle size significantly influence the re-distribution of particle-bound BTEX. Compared to heavy-duty traffic in commercial areas, light-duty traffic dominates the re-distribution of particles of all size ranges. In industrial areas, heavy-duty traffic re-distributes particles >75 μm, and light-duty traffic re-distributes particles <75 μm. In residential areas, light-duty traffic re-distributes particles >300 μm and <75 μm and heavy-duty traffic re-distributes particles in the 300-150 μm range. The study results provide important insights to improve stormwater quality modelling and the interpretation of modelling outcomes, contributing to safeguard the urban water environment. Copyright © 2018 Elsevier B.V. All rights reserved.

Blue-shifted and red-shifted hydrogen bonds: Theoretical study of the CH3CHO· · ·HNO complexes

NASA Astrophysics Data System (ADS)

Yang, Yong; Zhang, Weijun; Gao, Xiaoming

The blue-shifted and red-shifted H-bonds have been studied in complexes CH3CHO?HNO. At the MP2/6-31G(d), MP2/6-31+G(d,p) MP2/6-311++G(d,p), B3LYP/6-31G(d), B3LYP/6-31+G(d,p) and B3LYP/6-311++G(d,p) levels, the geometric structures and vibrational frequencies of complexes CH3CHO?HNO are calculated by both standard and CP-corrected methods, respectively. Complex A exhibits simultaneously red-shifted C bond H?O and blue-shifted N bond H?O H-bonds. Complex B possesses simultaneously two blue-shifted H-bonds: C bond H?O and N bond H?O. From NBO analysis, it becomes evident that the red-shifted C bond H?O H-bond can be explained on the basis of the two opposite effects: hyperconjugation and rehybridization. The blue-shifted C bond H?O H-bond is a result of conjunct C bond H bond strengthening effects of the hyperconjugation and the rehybridization due to existence of the significant electron density redistribution effect. For the blue-shifted N bond H?O H-bonds, the hyperconjugation is inhibited due to existence of the electron density redistribution effect. The large blue shift of the N bond H stretching frequency is observed because the rehybridization dominates the hyperconjugation.

Ill-defined causes of death in Brazil: a redistribution method based on the investigation of such causes

PubMed Central

França, Elisabeth; Teixeira, Renato; Ishitani, Lenice; Duncan, Bruce Bartholow; Cortez-Escalante, Juan José; de Morais, Otaliba Libânio; Szwarcwald, Célia Landman

2014-01-01

OBJECTIVE To propose a method of redistributing ill-defined causes of death (IDCD) based on the investigation of such causes. METHODS In 2010, an evaluation of the results of investigating the causes of death classified as IDCD in accordance with chapter 18 of the International Classification of Diseases (ICD-10) by the Mortality Information System was performed. The redistribution coefficients were calculated according to the proportional distribution of ill-defined causes reclassified after investigation in any chapter of the ICD-10, except for chapter 18, and used to redistribute the ill-defined causes not investigated and remaining by sex and age. The IDCD redistribution coefficient was compared with two usual methods of redistribution: a) Total redistribution coefficient, based on the proportional distribution of all the defined causes originally notified and b) Non-external redistribution coefficient, similar to the previous, but excluding external causes. RESULTS Of the 97,314 deaths by ill-defined causes reported in 2010, 30.3% were investigated, and 65.5% of those were reclassified as defined causes after the investigation. Endocrine diseases, mental disorders, and maternal causes had a higher representation among the reclassified ill-defined causes, contrary to infectious diseases, neoplasms, and genitourinary diseases, with higher proportions among the defined causes reported. External causes represented 9.3% of the ill-defined causes reclassified. The correction of mortality rates by the total redistribution coefficient and non-external redistribution coefficient increased the magnitude of the rates by a relatively similar factor for most causes, contrary to the IDCD redistribution coefficient that corrected the different causes of death with differentiated weights. CONCLUSIONS The proportional distribution of causes among the ill-defined causes reclassified after investigation was not similar to the original distribution of defined causes. Therefore, the redistribution of the remaining ill-defined causes based on the investigation allows for more appropriate estimates of the mortality risk due to specific causes. PMID:25210826

Ill-defined causes of death in Brazil: a redistribution method based on the investigation of such causes.

PubMed

França, Elisabeth; Teixeira, Renato; Ishitani, Lenice; Duncan, Bruce Bartholow; Cortez-Escalante, Juan José; Morais Neto, Otaliba Libânio de; Szwarcwald, Célia Landman

2014-08-01

OBJECTIVE To propose a method of redistributing ill-defined causes of death (IDCD) based on the investigation of such causes. METHODS In 2010, an evaluation of the results of investigating the causes of death classified as IDCD in accordance with chapter 18 of the International Classification of Diseases (ICD-10) by the Mortality Information System was performed. The redistribution coefficients were calculated according to the proportional distribution of ill-defined causes reclassified after investigation in any chapter of the ICD-10, except for chapter 18, and used to redistribute the ill-defined causes not investigated and remaining by sex and age. The IDCD redistribution coefficient was compared with two usual methods of redistribution: a) Total redistribution coefficient, based on the proportional distribution of all the defined causes originally notified and b) Non-external redistribution coefficient, similar to the previous, but excluding external causes. RESULTS Of the 97,314 deaths by ill-defined causes reported in 2010, 30.3% were investigated, and 65.5% of those were reclassified as defined causes after the investigation. Endocrine diseases, mental disorders, and maternal causes had a higher representation among the reclassified ill-defined causes, contrary to infectious diseases, neoplasms, and genitourinary diseases, with higher proportions among the defined causes reported. External causes represented 9.3% of the ill-defined causes reclassified. The correction of mortality rates by the total redistribution coefficient and non-external redistribution coefficient increased the magnitude of the rates by a relatively similar factor for most causes, contrary to the IDCD redistribution coefficient that corrected the different causes of death with differentiated weights. CONCLUSIONS The proportional distribution of causes among the ill-defined causes reclassified after investigation was not similar to the original distribution of defined causes. Therefore, the redistribution of the remaining ill-defined causes based on the investigation allows for more appropriate estimates of the mortality risk due to specific causes.

West Europe Report.

DTIC Science & Technology

1987-04-01

socialists, charm its deputies and reduce its unemployed electorate. In the next 3 months, it is only by relying on a motion of censure by the PRD...the Left, however, the phenomenon is even more complex. Or Cavaco Silva is not the classic leader of the haute bourgeoisie , residing in Cascäis or in...Austere, discreet in dress, with moderate habits, he does not reflect the good life of the exploiter. Simple and direct, he appeals to the

Secondary Education Credentials: A Military Enlistment Policy Dilemma

DTIC Science & Technology

1983-11-01

fall 1980 data from the National Center for Education Statistics , showing the enrollment rankings for church related schools to be: (1) Catholic, (2...34Unclassified 8ECURITY CLASSI•ICATION OP THIS PA•OEMn Data SnI..ed) Final Report HumIRRO FR.PRD.3.-22 Secondary Education Credentials: A Military...Commission of the States National Home Study Council* 11 •National Center for Education Statistics National Institute of Education 3 National Association of

Technology Demonstration of the Zero Emissions Chromium Electroplating System

DTIC Science & Technology

2008-02-01

Phase I trivalent chromium results ................................................................... 23 18 Phase II total chromium in PRD fluid results...0 xa B D F H J L Sam pies Figure 16. Phase II iron results. ERDC/CERL TR-05-35, Vol. 1 23 Trivalent Chromium Phase I Analysis for Phase I was...with the samples. Each sample was analyzed twice, and an average was computed. Figure 17 shows the results. ANAD has specified that Trivalent Chromium

Mitigation of cross-beam energy transfer in symmetric implosions on OMEGA using wavelength detuning

DOE PAGES

Edgell, D. H.; Follett, R. K.; Igumenshchev, I. V.; ...

2017-06-13

The effects of frequency detuning laser beams in direct-drive symmetric implosions were investigated with a 3-D cross-beam energy transfer (CBET) model. Our model shows that interactions between beams with relative angles between 45° and 90° are most significant for CBET in OMEGA direct-drive implosions. There is no net exchange in power between beams but there is significant redistribution of power from the ingoing central portion of the beam profile to the outgoing edge as it is exiting the plasma, reducing the total absorbed power. Furthermore, redistribution of laser power because of CBET increases the root-mean-square (rms) absorption nonuniformity by anmore » order of magnitude. CBET mitigation by shifting relative wavelengths of three groups of laser beams fed by each of the different beamlines was modeled. At an on-target wavelength shift of Δλ ~ 10 Å, the total laser absorption was maximized, and the rms absorption nonuniformity was near minimum. In order to completely decouple the three groups of beams from each other requires wavelength shifts Δλ > 30 Å.« less

Mitigation of cross-beam energy transfer in symmetric implosions on OMEGA using wavelength detuning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Edgell, D. H.; Follett, R. K.; Igumenshchev, I. V.

The effects of frequency detuning laser beams in direct-drive symmetric implosions were investigated with a 3-D cross-beam energy transfer (CBET) model. Our model shows that interactions between beams with relative angles between 45° and 90° are most significant for CBET in OMEGA direct-drive implosions. There is no net exchange in power between beams but there is significant redistribution of power from the ingoing central portion of the beam profile to the outgoing edge as it is exiting the plasma, reducing the total absorbed power. Furthermore, redistribution of laser power because of CBET increases the root-mean-square (rms) absorption nonuniformity by anmore » order of magnitude. CBET mitigation by shifting relative wavelengths of three groups of laser beams fed by each of the different beamlines was modeled. At an on-target wavelength shift of Δλ ~ 10 Å, the total laser absorption was maximized, and the rms absorption nonuniformity was near minimum. In order to completely decouple the three groups of beams from each other requires wavelength shifts Δλ > 30 Å.« less

The Complete Redistribution Approximation in Optically Thick Line-Driven Winds

NASA Astrophysics Data System (ADS)

Gayley, K. G.; Onifer, A. J.

2001-05-01

Wolf-Rayet winds are thought to exhibit large momentum fluxes, which has in part been explained by ionization stratification in the wind. However, it the cause of high mass loss, not high momentum flux, that remains largely a mystery, because standard models fail to achieve sufficient acceleration near the surface where the mass-loss rate is set. We consider a radiative transfer approximation that allows for the dynamics of optically thick Wolf-Rayet winds to be modeled without detailed treatment of the radiation field, called the complete redistribution approximation. In it, it is assumed that thermalization processes cause the photon frequencies to be completely randomized over the course of propagating through the wind, which allows the radiation field to be treated statistically rather than in detail. Thus the approach is similar to the statistical treatment of the line list used in the celebrated CAK approach. The results differ from the effectively gray treatment in that the radiation field is influenced by the line distribution, and the role of gaps in the line distribution is enhanced. The ramifications for the driving of large mass-loss rates is explored.

Evaluation of a Recirculating Dipper Well Combined with Ozone Sanitizer for Control of Foodborne Pathogens in Food Service Operations.

PubMed

Almeida, Giselle; Gibson, Kristen E

2016-09-01

In the retail food service industry, small countertop sinks, or dipper wells, are utilized to rinse and store serving utensils between uses. These dipper wells are designed to operate under a constant flow of water, which serves both to prevent the accumulation of microorganisms and to aid in the cleanliness of the dipper well itself. Here, a recirculating dipper well ozone sanitation system (DWOSS) was evaluated for the control and inactivation of Escherichia coli , Listeria innocua , PRD1 bacteriophage, and Staphylococcus aureus present on a stainless steel disher. In a low ozone (O 3 ) demand medium, the DWOSS achieved over a 5-log reduction for E. coli , L. innocua , and PRD1 at 30 s when exposed to 0.45 to 0.55 ppm of residual O 3 . A greater than 5-log total CFU reduction was achieved for S. aureus at a 600-s exposure time and 0.50 ppm of residual O 3 . When evaluated in the presence of high O 3 demand medium (10% skim milk), the DWOSS performed significantly better (P < 0.05) for all microbe-exposure time combinations compared with a conventional dipper well with respect to the reduction of microbes on the stainless steel disher. For example, at 30 s, the DWOSS achieved 4.37, 2.48, 1.38, and 1.31 greater log (CFU or PFU) reduction of E. coli , L. innocua , PRD1, and S. aureus , respectively, than a conventional dipper well. In addition, the DWOSS was evaluated under two neglect scenarios to determine its ability to control microbes in 10% skim milk medium on the stainless steel disher and within the dipper well basin itself over an extended period of use (2 h of use per day over 5 days). Considering the efficacy of the DWOSS unit against the microbes evaluated here, the integration of ozone into a dipper well could be a potential critical control point to reduce the incidence of microbial contamination during retail food service. To our knowledge, a dipper well with a cleaning-in-place sanitizing system is not currently available for use in the food service industry; and, thus, this is the first study to evaluate the efficacy of a cleaning-in-place dipper well.

Personal radiation detector at a high technology readiness level that satisfies DARPA's SN-13-47 and SIGMA program requirements

NASA Astrophysics Data System (ADS)

Ginzburg, D.; Knafo, Y.; Manor, A.; Seif, R.; Ghelman, M.; Ellenbogen, M.; Pushkarsky, V.; Ifergan, Y.; Semyonov, N.; Wengrowicz, U.; Mazor, T.; Kadmon, Y.; Cohen, Y.; Osovizky, A.

2015-06-01

There is a need to develop new personal radiation detector (PRD) technologies that can be mass produced. On August 2013, DARPA released a request for information (RFI) seeking innovative radiation detection technologies. In addition, on December 2013, a Broad Agency Announcement (BAA) for the SIGMA program was released. The RFI requirements focused on a sensor that should possess three main properties: low cost, high compactness and radioisotope identification capabilities. The identification performances should facilitate the detection of a hidden threat, ranging from special nuclear materials (SNM) to commonly used radiological sources. Subsequently, the BAA presented the specific requirements at an instrument level and provided a comparison between the current market status (state-of-the-art) and the SIGMA program objectives. This work presents an optional alternative for both the detection technology (sensor with communication output and without user interface) for DARPA's initial RFI and for the PRD required by the SIGMA program. A broad discussion is dedicated to the method proposed to fulfill the program objectives and to the selected alternative that is based on the PDS-GO design and technology. The PDS-GO is the first commercially available PRD that is based on a scintillation crystal optically coupled with a silicon photomultiplier (SiPM), a solid-state light sensor. This work presents the current performance of the instrument and possible future upgrades based on recent technological improvements in the SiPM design. The approach of utilizing the SiPM with a commonly available CsI(Tl) crystal is the key for achieving the program objectives. This approach provides the appropriate performance, low cost, mass production and small dimensions; however, it requires a creative approach to overcome the obstacles of the solid-state detector dark current (noise) and gain stabilization over a wide temperature range. Based on the presented results, we presume that the proposed approach of SiPM, with pixel size of 35 μm, coupled to a scintillation material (for gamma and neutron detection) ensures the availability and low cost of the key components. Furthermore, automated manufacturing process enables mass production, thereby fulfilling the SIGMA program requirements, both as a sensor (assimilated with mobile device) and as a full detection device.

Removal of microorganisms by deep well injection

NASA Astrophysics Data System (ADS)

Schijven, Jack F.; Medema, Gertjan; Vogelaar, Ad J.; Hassanizadeh, S. Majid

2000-08-01

The removal of bacteriophages MS2 and PRD1, spores of Clostridium bifermentans (R5) and Escherichia coli (WR1) by deep well injection into a sandy aquifer, was studied at a pilot field site in the southeast of the Netherlands. Injection water was seeded with the microorganisms for 5 days. Breakthrough was monitored for 93 days at 4 monitoring wells with their screens at a depth of about 310 m below surface. Within the first 8 m of soil passage, concentrations of MS2 and PRD1 were reduced by 6 log 10, that of R5 spores by 5 log 10 and that of WR1 by 7.5 log 10. Breakthrough of MS2 and R5 could also be followed at greater distances from the injection well. Concentrations of MS2 were reduced only by about 2 log 10 in the following 30 m, and reduction of concentrations of R5 was negligible. Apparently, attachment was greater during the first 8 m of aquifer passage. At the point of injection, the inactivation rate coefficient of free MS2 was found to be 0.081 day -1, that of free PRD1 0.060 day -1, and that of E. coli strain WR1 0.063 day -1. In injection water that had passed 8 m of soil, inactivation of MS2 phages was found to be less than in water from the injection well: 0.039 day -1. Probably, the higher inactivation rate of MS2 in water from the injection well may be ascribed to the activity of aerobic bacteria. Inactivation of the R5 spores was not significant. From geochemical mass balances, it could be deduced that within the first 8 m distance from the injection well, ferric oxyhydroxides precipitated as a consequence of pyrite oxidation, but not at larger distances. Ferric oxyhydroxides provide positively charged patches onto which fast attachment of the negatively charged microorganisms may take place. The non-linear logarithmic reduction of concentrations with distance may therefore be ascribed to preferable attachment of microorganisms to patches of ferric oxyhydroxides that are present within 8 m distance from the injection point, but not thereafter. Declogging of the injection well introduced hydrodynamic shear that remobilized MS2, which was then transported farther downstream.

A Curve Fitting Approach Using ANN for Converting CT Number to Linear Attenuation Coefficient for CT-based PET Attenuation Correction

NASA Astrophysics Data System (ADS)

Lai, Chia-Lin; Lee, Jhih-Shian; Chen, Jyh-Cheng

2015-02-01

Energy-mapping, the conversion of linear attenuation coefficients (μ) calculated at the effective computed tomography (CT) energy to those corresponding to 511 keV, is an important step in CT-based attenuation correction (CTAC) for positron emission tomography (PET) quantification. The aim of this study was to implement energy-mapping step by using curve fitting ability of artificial neural network (ANN). Eleven digital phantoms simulated by Geant4 application for tomographic emission (GATE) and 12 physical phantoms composed of various volume concentrations of iodine contrast were used in this study to generate energy-mapping curves by acquiring average CT values and linear attenuation coefficients at 511 keV of these phantoms. The curves were built with ANN toolbox in MATLAB. To evaluate the effectiveness of the proposed method, another two digital phantoms (liver and spine-bone) and three physical phantoms (volume concentrations of 3%, 10% and 20%) were used to compare the energy-mapping curves built by ANN and bilinear transformation, and a semi-quantitative analysis was proceeded by injecting 0.5 mCi FDG into a SD rat for micro-PET scanning. The results showed that the percentage relative difference (PRD) values of digital liver and spine-bone phantom are 5.46% and 1.28% based on ANN, and 19.21% and 1.87% based on bilinear transformation. For 3%, 10% and 20% physical phantoms, the PRD values of ANN curve are 0.91%, 0.70% and 3.70%, and the PRD values of bilinear transformation are 3.80%, 1.44% and 4.30%, respectively. Both digital and physical phantoms indicated that the ANN curve can achieve better performance than bilinear transformation. The semi-quantitative analysis of rat PET images showed that the ANN curve can reduce the inaccuracy caused by attenuation effect from 13.75% to 4.43% in brain tissue, and 23.26% to 9.41% in heart tissue. On the other hand, the inaccuracy remained 6.47% and 11.51% in brain and heart tissue when the bilinear transformation was used. Overall, it can be concluded that the bilinear transformation method resulted in considerable bias and the newly proposed calibration curve built by ANN could achieve better results with acceptable accuracy.

Intra-generational Redistribution under Public Pension Planning Based on Generation-based Funding Scheme

NASA Astrophysics Data System (ADS)

Banjo, Daisuke; Tamura, Hiroyuki; Murata, Tadahiko

In this paper, we propose a method of determining the pension in the generation-based funding scheme. In this proposal, we include two types of pensions in the scheme. One is the payment-amount related pension and the other is the payment-frequency related pension. We set the ratio of the total amount of payment-amount related pension to the total amount of both pensions, and simulate income gaps and the relationship between contributions and benefits for each individual when the proposed method is applied.

Windowed and Wavelet Analysis of Marine Stratocumulus Cloud Inhomogeneity

NASA Technical Reports Server (NTRS)

Gollmer, Steven M.; Harshvardhan; Cahalan, Robert F.; Snider, Jack B.

1995-01-01

To improve radiative transfer calculations for inhomogeneous clouds, a consistent means of modeling inhomogeneity is needed. One current method of modeling cloud inhomogeneity is through the use of fractal parameters. This method is based on the supposition that cloud inhomogeneity over a large range of scales is related. An analysis technique named wavelet analysis provides a means of studying the multiscale nature of cloud inhomogeneity. In this paper, the authors discuss the analysis and modeling of cloud inhomogeneity through the use of wavelet analysis. Wavelet analysis as well as other windowed analysis techniques are used to study liquid water path (LWP) measurements obtained during the marine stratocumulus phase of the First ISCCP (International Satellite Cloud Climatology Project) Regional Experiment. Statistics obtained using analysis windows, which are translated to span the LWP dataset, are used to study the local (small scale) properties of the cloud field as well as their time dependence. The LWP data are transformed onto an orthogonal wavelet basis that represents the data as a number of times series. Each of these time series lies within a frequency band and has a mean frequency that is half the frequency of the previous band. Wavelet analysis combined with translated analysis windows reveals that the local standard deviation of each frequency band is correlated with the local standard deviation of the other frequency bands. The ratio between the standard deviation of adjacent frequency bands is 0.9 and remains constant with respect to time. This ratio defined as the variance coupling parameter is applicable to all of the frequency bands studied and appears to be related to the slope of the data's power spectrum. Similar analyses are performed on two cloud inhomogeneity models, which use fractal-based concepts to introduce inhomogeneity into a uniform cloud field. The bounded cascade model does this by iteratively redistributing LWP at each scale using the value of the local mean. This model is reformulated into a wavelet multiresolution framework, thereby presenting a number of variants of the bounded cascade model. One variant introduced in this paper is the 'variance coupled model,' which redistributes LWP using the local standard deviation and the variance coupling parameter. While the bounded cascade model provides an elegant two- parameter model for generating cloud inhomogeneity, the multiresolution framework provides more flexibility at the expense of model complexity. Comparisons are made with the results from the LWP data analysis to demonstrate both the strengths and weaknesses of these models.

Potential influence of wildfire in modulating climate-induced forest redistribution in a central Rocky Mountain landscape

USGS Publications Warehouse

Campbell, John L.; Shinneman, Douglas

2017-01-01

IntroductionClimate change is expected to impose significant tension on the geographic distribution of tree species. Yet, tree species range shifts may be delayed by their long life spans, capacity to withstand long periods of physiological stress, and dispersal limitations. Wildfire could theoretically break this biological inertia by killing forest canopies and facilitating species redistribution under changing climate. We investigated the capacity of wildfire to modulate climate-induced tree redistribution across a montane landscape in the central Rocky Mountains under three climate scenarios (contemporary and two warmer future climates) and three wildfire scenarios (representing historical, suppressed, and future fire regimes).MethodsDistributions of four common tree species were projected over 90 years by pairing a climate niche model with a forest landscape simulation model that simulates species dispersal, establishment, and mortality under alternative disturbance regimes and climate scenarios.ResultsThree species (Douglas-fir, lodgepole pine, subalpine fir) declined in abundance over time, due to climate-driven contraction in area suitable for establishment, while one species (ponderosa pine) was unable to exploit climate-driven expansion of area suitable for establishment. Increased fire frequency accelerated declines in area occupied by Douglas-fir, lodgepole pine, and subalpine fir, and it maintained local abundance but not range expansion of ponderosa pine.ConclusionsWildfire may play a larger role in eliminating these conifer species along trailing edges of their distributions than facilitating establishment along leading edges, in part due to dispersal limitations and interspecific competition, and future populations may increasingly depend on persistence in locations unfavorable for their establishment.

REMORA: a pilot in the ocean of BioMoby web-services.

PubMed

Carrere, Sébastien; Gouzy, Jérôme

2006-04-01

Emerging web-services technology allows interoperability between multiple distributed architectures. Here, we present REMORA, a web server implemented according to the BioMoby web-service specifications, providing life science researchers with an easy-to-use workflow generator and launcher, a repository of predefined workflows and a survey system. Jerome.Gouzy@toulouse.inra.fr The REMORA web server is freely available at http://bioinfo.genopole-toulouse.prd.fr/remora, sources are available upon request from the authors.

A refined 2010-based VOC emission inventory and its improvement on modeling regional ozone in the Pearl River Delta Region, China.

PubMed

Yin, Shasha; Zheng, Junyu; Lu, Qing; Yuan, Zibing; Huang, Zhijiong; Zhong, Liuju; Lin, Hui

2015-05-01

Accurate and gridded VOC emission inventories are important for improving regional air quality model performance. In this study, a four-level VOC emission source categorization system was proposed. A 2010-based gridded Pearl River Delta (PRD) regional VOC emission inventory was developed with more comprehensive source coverage, latest emission factors, and updated activity data. The total anthropogenic VOC emission was estimated to be about 117.4 × 10(4)t, in which on-road mobile source shared the largest contribution, followed by industrial solvent use and industrial processes sources. Among the industrial solvent use source, furniture manufacturing and shoemaking were major VOC emission contributors. The spatial surrogates of VOC emission were updated for major VOC sources such as industrial sectors and gas stations. Subsector-based temporal characteristics were investigated and their temporal variations were characterized. The impacts of updated VOC emission estimates and spatial surrogates were evaluated by modeling O₃ concentration in the PRD region in the July and October of 2010, respectively. The results indicated that both updated emission estimates and spatial allocations can effectively reduce model bias on O₃ simulation. Further efforts should be made on the refinement of source classification, comprehensive collection of activity data, and spatial-temporal surrogates in order to reduce uncertainty in emission inventory and improve model performance. Copyright © 2015 Elsevier B.V. All rights reserved.

X-ray radiation detectors of ``scintillator-photoreceiving device type'' for industrial digital radiography with improved spatial resolution

NASA Astrophysics Data System (ADS)

Ryzhykov, V. D.; Lysetska, O. K.; Opolonin, O. D.; Kozin, D. N.

2003-06-01

Main types of photoreceivers used in X-ray digital radiography systems are luminescent screens that transfer the optical image onto charge collection instruments, which require cooling, and semiconductor silicon detectors, which limit the contrast sensitivity. We have developed and produced X-ray radiation detectors of "scintillator-photoreceiving device" (S-PRD) type, which are integrally located on the inverse side of the photodiode (PD). The receiving-converting circuit (RCC) is designed for data conversion into digital form and their input into PC. Software is provided for RCC control and image visualization. Main advantages of these detectors are high industrial resolution (3-5 line pairs per mm), detecting activity up to 20 μm, controlled sensitivity, low weight and small size, imaging low (0.1-0.3 mrad) object dose in real time. In this work, main characteristics of 32-, 64- and 1024-channel detectors of S-PRD type were studied and compared for X-ray sensitivity with S-PD detectors. Images of the tested objects have been obtained. Recommendations are given on the use of different scintillation materials, depending upon the purpose of a digital radiographic system. The detectors operate in a broad energy range of ionizing radiation, hence the size of the controlled object is not limited. The system is sufficiently powerful to ensure frontal (through two walls) observation of pipelines with wall thickness up to 10 cm.

Spatiotemporal variability of biogenic terpenoid emissions in Pearl River Delta, China, with high-resolution land-cover and meteorological data

NASA Astrophysics Data System (ADS)

Wang, Xuemei; Situ, Shuping; Guenther, Alex; Chen, Fei; Wu, Zhiyong; Xia, Beicheng; Wang, Tijian

2011-04-01

This study intended to provide 4-km gridded, hourly, year-long, regional estimates of terpenoid emissions in the Pearl River Delta (PRD), China. It combined Thematic Mapper images and local-survey data to characterize plant functional types, and used observed emission potential of biogenic volatile organic compounds (BVOC) from local plant species and high-resolution meteorological outputs from the MM5 model to constrain the MEGAN BVOC-emission model. The estimated annual emissions for isoprene, monoterpene and sesquiterpene are 95.55 × 106 kg C, 117.35 × 106 kg C and 9.77 × 106 kg C, respectively. The results show strong variabilities of terpenoid emissions spanning diurnal and seasonal time scales, which are mainly distributed in the remote areas (with more vegetation and less economic development) in PRD. Using MODIS PFTs data reduced terpenoid emissions by 27% in remote areas. Using MEGAN-model default emission factors led to a 24% increase in BVOC emission. The model errors of temperature and radiation in MM5 output were used to assess impacts of uncertainties in meteorological forcing on emissions: increasing (decreasing) temperature and downward shortwave radiation produces more (less) terpenoid emissions for July and January. Strong temporal variability of terpenoid emissions leads to enhanced ozone formation during midday in rural areas where the anthropogenic VOC emissions are limited.

Effects of different irrigation practices using treated wastewater on tomato yields, quality, water productivity, and soil and fruit mineral contents.

PubMed

Demir, Azize Dogan; Sahin, Ustun

2017-11-01

Wastewater use in agricultural irrigation is becoming a common practice in order to meet the rising water demands in arid and semi-arid regions. The study was conducted to determine the effects of the full (FI), deficit (DI), and partial root-zone drying (PRD) irrigation practices using treated municipal wastewater (TWW) and freshwater (FW) on tomato yield, water use, fruit quality, and soil and fruit heavy metal concentrations. The TWW significantly increased marketable yield compared to the FW, as well as decreased water consumption. Therefore, water use efficiency (WUE) in the TWW was significantly higher than in the FW. Although the DI and the PRD practices caused less yields, these practices significantly increased WUE values due to less irrigation water applied. The water-yield linear relationships were statistically significant. TWW significantly increased titratable acidity and vitamin C contents. Reduced irrigation provided significantly lower titratable acidity, vitamin C, and lycopene contents. TWW increased the surface soil and fruit mineral contents in response to FW. Greater increases were observed under FI, and mineral contents declined with reduction in irrigation water. Heavy metal accumulation in soils was within safe limits. However, Cd and Pb contents in fruits exceeded standard limits given by FAO/WHO. Higher metal pollution index values determined for fruits also indicated that TWW application, especially under FI, might cause health risks in long term.

Distribution, sources, and potential toxicological significance of PAHs in drinking water sources within the Pearl River Delta.

PubMed

An, Taicheng; Qiao, Meng; Li, Guiying; Sun, Hongwei; Zeng, Xiangying; Fu, Jiamo

2011-05-01

The Pearl River Delta (PRD) region is one of the most population-dense areas in China. The safety of its drinking source water is essential to human health. Polycyclic aromatic hydrocarbons (PAHs) have attracted attention from the scientific community and the general public due to their toxicity and wide distribution in the global environment. In this work, PAHs pollution levels from the drinking source water in nine main cities within the PRD were investigated. ∑15 PAHs concentrations during the wet season varied from 32.0 to 754.8 ng L(-1) in the dissolved phase, and from 13.4 to 3017.8 ng L(-1) in the particulate phase. During the dry season, dissolved PAHs ranged from 48.1 to 113.6 ng L(-1), and particulate PAHs from 8.6 to 69.6 ng L(-1). Overall, ∑15 PAHs concentrations were extremely high in the XC and ZHQ stations during the wet season in 2008 and 2009. In most sites, PAHs originated from mixed sources. Hazard ratios based on non-cancerous and cancerous risks were extremely higher in XC compared with the others during the wet season, though they were much less than 1. Nevertheless, risks caused by the combined toxicity of ∑15 PAHs and other organics should be seriously considered. PAHs toxic equivalent quantities ranged from 0.508 to 177.077 ng L(-1).

Pelvic radiation disease: Updates on treatment options

PubMed Central

Frazzoni, Leonardo; La Marca, Marina; Guido, Alessandra; Morganti, Alessio Giuseppe; Bazzoli, Franco; Fuccio, Lorenzo

2015-01-01

Pelvic cancers are among the most frequently diagnosed neoplasms and radiotherapy represents one of the main treatment options. The irradiation field usually encompasses healthy intestinal tissue, especially of distal large bowel, thus inducing gastrointestinal (GI) radiation-induced toxicity. Indeed, up to half of radiation-treated patients say that their quality of life is affected by GI symptoms (e.g., rectal bleeding, diarrhoea). The constellation of GI symptoms - from transient to long-term, from mild to very severe - experienced by patients who underwent radiation treatment for a pelvic tumor have been comprised in the definition of pelvic radiation disease (PRD). A correct and evidence-based therapeutic approach of patients experiencing GI radiation-induced toxicity is mandatory. Therapeutic non-surgical strategies for PRD can be summarized in two broad categories, i.e., medical and endoscopic. Of note, most of the studies have investigated the management of radiation-induced rectal bleeding. Patients with clinically significant bleeding (i.e., causing chronic anemia) should firstly be considered for medical management (i.e., sucralfate enemas, metronidazole and hyperbaric oxygen); in case of failure, endoscopic treatment should be implemented. This latter should be considered the first choice in case of acute, transfusion requiring, bleeding. More well-performed, high quality studies should be performed, especially the role of medical treatments should be better investigated as well as the comparative studies between endoscopic and hyperbaric oxygen treatments. PMID:26677440

New Insights on the Nitrogen Footprint of a Coastal Megalopolis from Coral-Hosted Symbiodinium δ15N.

PubMed

Wong, C W Martin; Duprey, Nicolas N; Baker, David M

2017-02-21

The development of megalopolises in coastal areas is often linked with severe eutrophication, requiring mitigation of anthropogenic dissolved inorganic nitrogen (DIN) pollution. Yet, identifying the DIN-sources responsible for eutrophication is challenging, hampering mitigation efforts. Here, we utilize the stable nitrogen isotope ratio of endosymbiotic dinoflagellate Symbiodinium spp. (δ 15 N sym ) associated with the hard coral Porites to trace DIN sources in one of the most urbanized areas of the planet: the Pearl River Delta (PRD). The mean δ 15 N sym value found in the coastal waters of Hong Kong (HK), located on the eastern edge of the PRD, (7.4‰ ± 1.2‰) was +2.7‰ higher than at Dongsha Atoll, a reference site unaffected by anthropogenic-DIN (4.7‰ ± 0.4‰). The isotopic enrichment suggested a consistent dominance of DIN deriving from local and regional sewage discharges on the eastern edge of HK. Furthermore, the strong depletion of the summer δ 15 N sym value (-1.6‰) observed in southern HK revealed that the Pearl River plume strongly modulates the coastal DIN pool. Our results revealed the value of benthic marine organisms' δ 15 N for deciphering the complex dynamics of coastal eutrophication and highlighted the pivotal role of transboundary coordination in DIN-pollution mitigation.

Viral transport in a sand and gravel aquifer under field pumping conditions.

PubMed

Woessner, W W; Ball, P N; DeBorde, D C; Troy, T L

2001-01-01

Ground water supplies contaminated with microbes cause more than 50% of the water-borne disease outbreaks in the United States. Proposed regulations suggest natural disinfection as a possible mechanism to treat microbe-impacted ground water under favorable conditions. However, the usefulness of current models employed to predict viral transport and natural attenuation rates is limited by the absence of field scale calibration data. At a remote floodplain aquifer in western Montana, the bacteriophages MS2, phiX174, and PRD1; attenuated poliovirus type-1 (CHAT strain); and bromide were seeded as a slug 21.5 m from a well pumping at a steady rate of 408 L/min. Over the 47-hour duration of the test, resulting in the exchange of 12 to 13 pore volumes, 77% of the bromide, 55% of the PRD1, 17% of the MS2, 7% of the phiX174, and 0.12% of the poliovirus masses were recovered at the pumping well. Virus transport behavior was controlled by mechanical dispersion, preferential flow, time-dependent nonreversible and reversible attachment, and apparent mass transfer to immobile domains within the sand and gravel dominated aquifer. The percentage of virus recovery appears correlated with reported viral isoelectric point (pI) values. Successful modeling of viral transport in coarse-grained aquifers will require separation of viral specific properties from reported lumped viral-transport system parameters.

Removal of Surrogate Bacteriophages and Enteric Viruses from Seeded Environmental Waters Using a Semi-technical Ultrafiltration Unit.

PubMed

Frohnert, Anne; Kreißel, Katja; Lipp, Pia; Dizer, Halim; Hambsch, Beate; Szewzyk, Regine; Selinka, Hans-Christoph

2015-03-19

Experiments to determine the removal of viruses in different types of water (surface water from two reservoirs for drinking water treatment, treated groundwater and groundwater contaminated with either 5 or 30 % of wastewater) by ultrafiltration were performed with a semi-technical ultrafiltration unit. Concentrations of human adenoviruses (HAdVs), murine norovirus (MNV), and the bacteriophages MS2, ΦX174 and PRD1 were measured in the feed water and the filtrate, and log removal values were calculated. Bacteria added to the feed water were not detected in the filtrates. In contrast, in most cases viruses and bacteriophages were still present in the filtrates: log removal values were in the range of 1.4-6.3 depending on virus sizes and water qualities. Best removals were observed with bacteriophage PRD1 and HAdVs, followed by MNV and phages MS2 and ΦX174. Virus size, however, was not the only criterion for efficient removal. In diluted wastewater as compared to drinking water and uncontaminated environmental waters, virus removal was clearly higher for all viruses, most likely due to higher membrane fouling. For quality assessment purposes of membrane filtration efficiencies with regard to the elimination of human viruses the small bacteriophages MS2 and ΦX174 should be used as conservative viral indicators.

Industrial sector-based volatile organic compound (VOC) source profiles measured in manufacturing facilities in the Pearl River Delta, China.

PubMed

Zheng, Junyu; Yu, Yufan; Mo, Ziwei; Zhang, Zhou; Wang, Xinming; Yin, Shasha; Peng, Kang; Yang, Yang; Feng, Xiaoqiong; Cai, Huihua

2013-07-01

Industrial sector-based VOC source profiles are reported for the Pearl River Delta (PRD) region, China, based source samples (stack emissions and fugitive emissions) analyzed from sources operating under normal conditions. The industrial sectors considered are printing (letterpress, offset and gravure printing processes), wood furniture coating, shoemaking, paint manufacturing and metal surface coating. More than 250 VOC species were detected following US EPA methods TO-14 and TO-15. The results indicated that benzene and toluene were the major species associated with letterpress printing, while ethyl acetate and isopropyl alcohol were the most abundant compounds of other two printing processes. Acetone and 2-butanone were the major species observed in the shoemaking sector. The source profile patterns were found to be similar for the paint manufacturing, wood furniture coating, and metal surface coating sectors, with aromatics being the most abundant group and oxygenated VOCs (OVOCs) as the second largest contributor in the profiles. While OVOCs were one of the most significant VOC groups detected in these five industrial sectors in the PRD region, they have not been reported in most other source profile studies. Such comparisons with other studies show that there are differences in source profiles for different regions or countries, indicating the importance of developing local source profiles. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

Collective religiosity and the gender gap in attitudes towards economic redistribution in 86 countries, 1990-2008.

PubMed

Jaime-Castillo, Antonio M; Fernández, Juan J; Valiente, Celia; Mayrl, Damon

2016-05-01

What is the relationship between gender and the demand for redistribution? Because, on average, women face more economic deprivation than men, in many countries women favor redistribution more than men. However, this is not the case in a number of other countries, where women do not support redistribution more than men. To explain this cross-national paradox, we stress the role of collective religiosity. In many religions, theological principles both militate against public policies designed to redistribute income, and also promote traditionally gendered patterns of work and family involvement. Hence, we hypothesize that, in those countries where religion remains influential either through closer church-state ties or an intensely religious population, men and women should differ less in their attitudes towards redistribution. Drawing upon the World Values Survey, we estimate three-level regression models that test our religiosity-based approach and two alternative explanations in 86 countries and 175 country-years. The results are consistent with our hypothesis. Moreover, in further support of our theoretical approach, societal religiosity undermines pro-redistribution preferences more among women than men. Our findings suggest that collective religiosity matters more to the gender gap in redistributive attitudes than traditional political and labor force factors. Copyright © 2016 Elsevier Inc. All rights reserved.

[Effects of rainfall intensity on rainfall infiltration and redistribution in soil on Loess slope land].

PubMed

Li, Yi; Shao, Ming'an

2006-12-01

With simulation test, this paper studied the patterns of rainfall infiltration and redistribution in soil on typical Loess slope land, and analyzed the quantitative relations between the infiltration and redistribution and the movement of soil water and mass, with rainfall intensity as the main affecting factor. The results showed that rainfall intensity had significant effects on the rainfall infiltration and water redistribution in soil, and the microcosmic movement of soil water. The larger the rainfall intensity, the deeper the wetting front of rainfall infiltration and redistribution was, and the wetting front of soil water redistribution had a slower increase velocity than that of rainfall infiltration. The power function of the wetting front with time, and also with rainfall intensity, was fitted well. There was also a quantitative relation between the wetting front of rainfall redistribution and the duration of rainfall. The larger the rainfall intensity, the higher the initial and steady infiltration rates were, and the cumulative infiltration increased faster with time. Moreover, the larger the rainfall intensity, the smaller the wetting front difference was at the top and the end of the slope. With the larger rainfall intensity, both the difference of soil water content and its descending trend between soil layers became more obvious during the redistribution process on slope land.

Redistribution of energy available for ocean mixing by long-range propagation of internal waves.

PubMed

Alford, Matthew H

2003-05-08

Ocean mixing, which affects pollutant dispersal, marine productivity and global climate, largely results from the breaking of internal gravity waves--disturbances propagating along the ocean's internal stratification. A global map of internal-wave dissipation would be useful in improving climate models, but would require knowledge of the sources of internal gravity waves and their propagation. Towards this goal, I present here computations of horizontal internal-wave propagation from 60 historical moorings and relate them to the source terms of internal waves as computed previously. Analysis of the two most energetic frequency ranges--near-inertial frequencies and semidiurnal tidal frequencies--reveals that the fluxes in both frequency bands are of the order of 1 kW x m(-1) (that is, 15-50% of the energy input) and are directed away from their respective source regions. However, the energy flux due to near-inertial waves is stronger in winter, whereas the tidal fluxes are uniform throughout the year. Both varieties of internal waves can thus significantly affect the space-time distribution of energy available for global mixing.

Effects of income redistribution on the evolution of cooperation in spatial public goods games

NASA Astrophysics Data System (ADS)

Pei, Zhenhua; Wang, Baokui; Du, Jinming

2017-01-01

Income redistribution is the transfer of income from some individuals to others directly or indirectly by means of social mechanisms, such as taxation, public services and so on. Employing a spatial public goods game, we study the influence of income redistribution on the evolution of cooperation. Two kinds of evolutionary models are constructed, which describe local and global redistribution of income respectively. In the local model, players have to pay part of their income after each PGG and the accumulated income is redistributed to the members. While in the global model, all the players pay part of their income after engaging in all the local PGGs, which are centred on himself and his nearest neighbours, and the accumulated income is redistributed to the whole population. We show that the cooperation prospers significantly with increasing income expenditure proportion in the local redistribution of income, while in the global model the situation is opposite. Furthermore, the cooperation drops dramatically from the maximum curvature point of income expenditure proportion. In particular, the intermediate critical points are closely related to the renormalized enhancement factors.

How do emission patterns in megacities affect regional air pollution?

NASA Astrophysics Data System (ADS)

Heil, A.; Richter, C.; Schroeder, S.; Schultz, M. G.

2010-12-01

Megacities around the world show distinctly different emission patterns in terms of absolute amounts and emission ratios of individual chemical compounds due to varying socio-economic developments and technological standards. The emission patterns influence the chemical reactivity of the urban pollution plume, and hence determine air quality in and around megacity areas. In this study, which is part of the European project CITYZEN (megaCITY - Zoom for the ENvironment), the effects of emission changes in four selected megacity areas on air pollution were investigated: BeNeLux (BNL), Istanbul (IST), Pearl River Delta (PRD) and Sao Paulo (SAP). The study aims at answering the question: how would air pollution in megacity X change if it had the same urban emissions per capita as megacity Y? Model simulations with the global chemistry climate model ECHAM5-MOZ were carried out for the year 2001 using a resolution of about 2 degrees in the horizontal and of 31 levels (surface to 10 hPa) in the vertical. The model was driven by meteorological input data from the ECMWF ERA Interim reanalysis. Emissions were taken from the gridded global ACCMIP emission inventory recently established for use in chemistry-climate simulations in connection to the IPCC-AR5 assessments (Lamarque et al. 2010). We carried out sensitivity simulations where emission patterns from each of the megacity areas were replaced by those from all others. This was done on the basis of the per capita emissions for each species and sector averaged over the respective region. Total per capita CO and NMVOC emissions are highest in PRD and lowest in SAP while total per capita NOx emissions are highest in BNL and lowest in SAP. There are strong differences in the relative contribution of the urban sectors to total emissions of individual compounds. As a result, each of the four megacity areas exhibits a very characteristic NMVOC speciation profile which determines the NMVOC-related photochemical ozone (O_3) creation potential. Compared to the emissions used in the reference simulation, changing per capita urban emissions in BNL into those of IST or SAP will lead to reduction in total megacity emissions of CO and NOx by between 40 to 80% and of between 5 to 20% for NMVOC. When the per capita emissions for PRD are applied, only NOx decreases (by 50%) while CO and NMVOC increase by between 20 and 40%. Similar changes occur when the emissions are interchanged in the other three regions. Annual mean ambient O_3 concentrations in the entire BNL megacity domain are elevated by 3 to 8 ppb in all sensitivity runs and a significant effect is also found outside the main megacity area. In the IST and PRD megacity areas, O_3 levels increase or decrease by 1 to 5 ppb when the per capita emissions from the other regions are used. For the SAP megacity area, all scenarios lead to a reduction of annual mean O_3 levels by more than 4 ppb in the north-western section of the domain while increases up to 3 ppb are predicted for some southern regions. We will also present an analysis of changes in the photochemical regimes related to altered emission patterns. The study can contribute directly to the development of air pollution abatement strategies.

Managing consequences of climate-driven species redistribution requires integration of ecology, conservation and social science.

PubMed

Bonebrake, Timothy C; Brown, Christopher J; Bell, Johann D; Blanchard, Julia L; Chauvenet, Alienor; Champion, Curtis; Chen, I-Ching; Clark, Timothy D; Colwell, Robert K; Danielsen, Finn; Dell, Anthony I; Donelson, Jennifer M; Evengård, Birgitta; Ferrier, Simon; Frusher, Stewart; Garcia, Raquel A; Griffis, Roger B; Hobday, Alistair J; Jarzyna, Marta A; Lee, Emma; Lenoir, Jonathan; Linnetved, Hlif; Martin, Victoria Y; McCormack, Phillipa C; McDonald, Jan; McDonald-Madden, Eve; Mitchell, Nicola; Mustonen, Tero; Pandolfi, John M; Pettorelli, Nathalie; Possingham, Hugh; Pulsifer, Peter; Reynolds, Mark; Scheffers, Brett R; Sorte, Cascade J B; Strugnell, Jan M; Tuanmu, Mao-Ning; Twiname, Samantha; Vergés, Adriana; Villanueva, Cecilia; Wapstra, Erik; Wernberg, Thomas; Pecl, Gretta T

2018-02-01

Climate change is driving a pervasive global redistribution of the planet's species. Species redistribution poses new questions for the study of ecosystems, conservation science and human societies that require a coordinated and integrated approach. Here we review recent progress, key gaps and strategic directions in this nascent research area, emphasising emerging themes in species redistribution biology, the importance of understanding underlying drivers and the need to anticipate novel outcomes of changes in species ranges. We highlight that species redistribution has manifest implications across multiple temporal and spatial scales and from genes to ecosystems. Understanding range shifts from ecological, physiological, genetic and biogeographical perspectives is essential for informing changing paradigms in conservation science and for designing conservation strategies that incorporate changing population connectivity and advance adaptation to climate change. Species redistributions present challenges for human well-being, environmental management and sustainable development. By synthesising recent approaches, theories and tools, our review establishes an interdisciplinary foundation for the development of future research on species redistribution. Specifically, we demonstrate how ecological, conservation and social research on species redistribution can best be achieved by working across disciplinary boundaries to develop and implement solutions to climate change challenges. Future studies should therefore integrate existing and complementary scientific frameworks while incorporating social science and human-centred approaches. Finally, we emphasise that the best science will not be useful unless more scientists engage with managers, policy makers and the public to develop responsible and socially acceptable options for the global challenges arising from species redistributions. © 2017 Cambridge Philosophical Society.

Effects of tree roots on shallow landslides distribution and frequency in the European Alps using a new physically-based discrete element model

NASA Astrophysics Data System (ADS)

Cohen, Denis; Schwarz, Massimiliano

2017-04-01

Shallow landslides are hillslope processes that play a key role in shaping landscapes in forested catchments. Shallow landslides are, in some regions, the dominant regulating mechanisms by which soil is delivered from the hillslopes to steep channels and fluvial systems. Several studies have highlighted the importance of roots to better understand mechanisms of root reinforcement and their contributions to the stabilization of hillslopes. In this context, the spatio-temporal distribution of root reinforcement has a major repercussion on the dynamic of sediment transport at the catchment scale and on the availability of productive soils. Here we present a new model for shallow slope stability calculations, SOSlope, that specifically considers the effects of root reinforcement on shallow landslide initiation. The model is a strain-step discrete element model that reproduces the self-organized redistribution of forces on a slope during rainfall-triggered shallow landslides. Tree roots govern tensile and compressive force redistribution and determine the stability of the slope, the timing, location, and dimension of the failure mass. We use SOSlope to quantify the role of protection forest in several localities in the European Alps, making use of detailed field measurements of root densities and root-size distribution, and root tensile and compressive strength for three species common in the Alps (spruce, fir, and beech) to compute landslide distributions and frequency during landslide-triggering rainfall events. We show the mechanisms by which tree roots impart reinforcement to slopes and offer protection against shallow landslides.

Impact of recent land use and climate changes on sediment and pollutant redistribution in small catchments within the Seim River Basin (Kursk Region, European Russia)

NASA Astrophysics Data System (ADS)

Belyaev, Vladimir; Ivanova, Nadezda; Ivanov, Maxim; Bondarev, Valery; Lugovoy, Nikolay; Aseeva, Elena; Malyutina, Alisa

2017-04-01

It is widely accepted that changes of land use or climatic conditions can exert profound impacts on river basin sediment budgets and associated particle-bound pollutant redistribution patterns at different temporal and spatial scales. It can be especially difficult to distinguish relative importance of particular factors when the changes occur more or less within the same time frame. Such situation is typical for most parts of the agricultural belt of Russia, as period of economic downfall associated with collapse of the former Soviet Union and later gradual recovery practically coincides with period of the most significant climate changes observed in the late 20th - early 21st Centuries. Therefore it seems interesting and important to consider possible changes of fluvial systems responses within the period from 1980s to the present under different spatial scales. Here we plan to present results of the almost 10-year period of investigations of sediment and associated pollutant redistribution spatial and temporal patterns in several small catchments within the Seim River Basin (Kursk Region, European Russia). Studies dealt with small catchments and small river basins in scales from 1-2 km2 to 200 km2 located in different parts of the main basin. Works carried out included detailed geomorphic surveys, soil and sediment sections and cores description and sampling in different locations (undisturbed, erosion, transit, deposition), remote sensing data and morphometric analysis, soil erosion modeling. Integration of the results allowed constructing sediment budgets, in most cases, for two time intervals (approximately - pre-1986 and post-1986, as the Chernobyl-derived 137Cs has been an important time mark at all the case study sites). It has been found out that combination of several major tendencies including abandonment and recultivation of arable fields, notable decrease of winter-frozen topsoil layer thickness and increase of heavy summer rainstorms magnitude and frequency are responsible for the observed variability of sediment and associated contaminant redistribution patterns.

Hybrid simulations of Alfvén modes driven by energetic particles

NASA Astrophysics Data System (ADS)

Zhu, J.; Ma, Z. W.; Wang, S.

2016-12-01

A hybrid kinetic-magnetohydrodynamic code (CLT-K) is developed to study nonlinear dynamics of Alfvén modes driven by energetic particles (EP). A n = 2 toroidicity-induced discrete shear Alfvén eigenmode (TAE)-type energetic particle mode (EPM) with two dominant poloidal harmonics (m = 2 and 3) is first excited and its frequency remains unchanged in the early phase. Later, a new branch of the n = 2 frequency with a single dominant poloidal mode (m = 3) splits from the original TAE-type EPM. The new single m EPM (m = 3) slowly moves radially outward with the downward chirping of the frequency and the mode amplitude remains at a higher level. The original EPM remains at its original position without the frequency chirping, but its amplitude decays with time. Finally, the m = 3 EPM becomes dominant and the frequency falls into the β-induced gap of the Alfvén continuum. The redistribution of the δf in the phase space is consistent with the mode frequency downward chirping and the drifting direction of the resonance region is mainly due to the biased free energy profile. The transition from a TAE-type EPM to a single m EPM is mainly caused by extension of the p = 0 trapped particle resonance in the phase space.

Evidence Report: Risk of Decompression Sickness (DCS)

NASA Technical Reports Server (NTRS)

Conkin, Johnny; Norcross, Jason R.; Wessel, James H. III; Abercromby, Andrew F. J.; Klein, Jill S.; Dervay, Joseph P.; Gernhardt, Michael L.

2013-01-01

The Risk of Decompression Sickness (DCS) is identified by the NASA Human Research Program (HRP) as a recognized risk to human health and performance in space, as defined in the HRP Program Requirements Document (PRD). This Evidence Report provides a summary of the evidence that has been used to identify and characterize this risk. Given that tissue inert gas partial pressure is often greater than ambient pressure during phases of a mission, primarily during extravehicular activity (EVA), there is a possibility that decompression sickness may occur.

Panama: Political and Economic Conditions and U.S. Relations

DTIC Science & Technology

2008-07-31

but the September 1, 2007 election of Pedro Miguel González to head Panama’s legislature for one year delayed consideration. González is wanted in...term. Current Assembly president Pedro Miguel González, wanted in the United States for his alleged role in the murder of a U.S. serviceman in Panama in...Administration negotiated the Panama Canal Treaties. On September 1, 2007, Panama’s Legislative Assembly elected Pedro Miguel González of the ruling PRD

The U.S. Navy’s Consultant Development and Qualification Program: Origin and Issues.

DTIC Science & Technology

1984-03-01

Areasoe Senior Master I Capability Intern Consultant Consultant Consultant I MARKETING Strategy 1--------------- 21 Ijplementation 1 --------- I...SENIOR MASTER INTERN CONSULTANT CONSULTANT CONSULTANT A. MARKETING A.1 Develop Marketing Strategy Program 1 11 A.2 Implement Marketing Program 1 1 1 2 A.3...Qualification Criteria for: Degree of PROFICIENCY LT 0. D. EFFORT SEP 1980 SEP 1983 Date Reported PRD 1 2 3 4 A. MARKETING A.1 Develop Marketing Strategy (1, 1

Comparison of Permanent Change of Station Costs for Women and Men Transferred Prematurely from Ships (Computer Diskette).

DTIC Science & Technology

requirements: Post-script. The Objective of this report was to determine whether transferring pregnant women from ships costs the Navy more permanent...change of station (PCS) funds than transferring men and nonpregnant women information was extracted from the enlisted master record concerning gender...from gender-integrated afloat units. The direct costs of transfer prior to PRD was compared for men and women and an estimate of PCS costs, if the ships were not gender-integrated, was also calculated.

United States Army Unilateral and Coalition Operations in the 1965 Dominican Republic Intervention

DTIC Science & Technology

1986-11-01

perceptions held by Latin American leaders. This study identifies several differe- es in perception within the western hemisphere regarding both the possibe...k:’. A- k ’- ’-P’ýJ A A -AA Juan Bosch and his newly formed Dominican Revolutionary Party ( Partido Revolucionario Dominicano), known as the PRD...Ie inon, wetnen, And teenagaer alikeO Meld iemmeiedlally i-41allei upcn his servi~c tchiofs to ,.,uLbia. their 1’nc~ es an#) crush fth rebellion. At

Support for redistribution is shaped by compassion, envy, and self-interest, but not a taste for fairness.

PubMed

Sznycer, Daniel; Lopez Seal, Maria Florencia; Sell, Aaron; Lim, Julian; Porat, Roni; Shalvi, Shaul; Halperin, Eran; Cosmides, Leda; Tooby, John

2017-08-01

Why do people support economic redistribution? Hypotheses include inequity aversion, a moral sense that inequality is intrinsically unfair, and cultural explanations such as exposure to and assimilation of culturally transmitted ideologies. However, humans have been interacting with worse-off and better-off individuals over evolutionary time, and our motivational systems may have been naturally selected to navigate the opportunities and challenges posed by such recurrent interactions. We hypothesize that modern redistribution is perceived as an ancestral scene involving three notional players: the needy other, the better-off other, and the actor herself. We explore how three motivational systems-compassion, self-interest, and envy-guide responses to the needy other and the better-off other, and how they pattern responses to redistribution. Data from the United States, the United Kingdom, India, and Israel support this model. Endorsement of redistribution is independently predicted by dispositional compassion, dispositional envy, and the expectation of personal gain from redistribution. By contrast, a taste for fairness, in the sense of ( i ) universality in the application of laws and standards, or ( ii ) low variance in group-level payoffs, fails to predict attitudes about redistribution.

Support for redistribution is shaped by compassion, envy, and self-interest, but not a taste for fairness

PubMed Central

Lopez Seal, Maria Florencia; Sell, Aaron; Lim, Julian; Porat, Roni; Halperin, Eran; Cosmides, Leda; Tooby, John

2017-01-01

Why do people support economic redistribution? Hypotheses include inequity aversion, a moral sense that inequality is intrinsically unfair, and cultural explanations such as exposure to and assimilation of culturally transmitted ideologies. However, humans have been interacting with worse-off and better-off individuals over evolutionary time, and our motivational systems may have been naturally selected to navigate the opportunities and challenges posed by such recurrent interactions. We hypothesize that modern redistribution is perceived as an ancestral scene involving three notional players: the needy other, the better-off other, and the actor herself. We explore how three motivational systems—compassion, self-interest, and envy—guide responses to the needy other and the better-off other, and how they pattern responses to redistribution. Data from the United States, the United Kingdom, India, and Israel support this model. Endorsement of redistribution is independently predicted by dispositional compassion, dispositional envy, and the expectation of personal gain from redistribution. By contrast, a taste for fairness, in the sense of (i) universality in the application of laws and standards, or (ii) low variance in group-level payoffs, fails to predict attitudes about redistribution. PMID:28716928

Maxwell-Wagner relaxation in electrical imaging.

PubMed

Korjenevsky, A V

2005-04-01

The electric field tomography (EFT) method exploits interaction of high-frequency electric field with an inhomogeneous conductive medium without contact with the electrodes. The interaction is accompanied by a high-frequency redistribution of free charges inside the medium and leads to small and regular phase shifts of the field in the area surrounding an object. Such a kind of phenomenon is referred to as the Maxwell-Wagner relaxation. Measuring the perturbations of the field using the set of electrodes placed around the object enables us to reconstruct the internal structure of the medium, generally the spatial distribution of a nonlinear combination of permittivity and resistivity. In the case of biomedical applications the result of measurements is determined mainly by the resistivity of the tissues. Three-dimensional simulation based on the finite element method has demonstrated the feasibility of the technique.

Cost-effective sampling of ¹³⁷Cs-derived net soil redistribution: part 1--estimating the spatial mean across scales of variation.

PubMed

Li, Y; Chappell, A; Nyamdavaa, B; Yu, H; Davaasuren, D; Zoljargal, K

2015-03-01

The (137)Cs technique for estimating net time-integrated soil redistribution is valuable for understanding the factors controlling soil redistribution by all processes. The literature on this technique is dominated by studies of individual fields and describes its typically time-consuming nature. We contend that the community making these studies has inappropriately assumed that many (137)Cs measurements are required and hence estimates of net soil redistribution can only be made at the field scale. Here, we support future studies of (137)Cs-derived net soil redistribution to apply their often limited resources across scales of variation (field, catchment, region etc.) without compromising the quality of the estimates at any scale. We describe a hybrid, design-based and model-based, stratified random sampling design with composites to estimate the sampling variance and a cost model for fieldwork and laboratory measurements. Geostatistical mapping of net (1954-2012) soil redistribution as a case study on the Chinese Loess Plateau is compared with estimates for several other sampling designs popular in the literature. We demonstrate the cost-effectiveness of the hybrid design for spatial estimation of net soil redistribution. To demonstrate the limitations of current sampling approaches to cut across scales of variation, we extrapolate our estimate of net soil redistribution across the region, show that for the same resources, estimates from many fields could have been provided and would elucidate the cause of differences within and between regional estimates. We recommend that future studies evaluate carefully the sampling design to consider the opportunity to investigate (137)Cs-derived net soil redistribution across scales of variation. Copyright © 2014 Elsevier Ltd. All rights reserved.

The evolution of rotating stars. III - Predicted surface rotation velocities for stars which conserve total angular momentum

NASA Technical Reports Server (NTRS)

Endal, A. S.; Sofia, S.

1979-01-01

Predicted surface rotation velocities for Population I stars at 10, 7, 5, 3, and 1.5 solar masses are presented. The surface velocities were computed for angular momentum with no radial redistribution, complete redistribution, and partial redistribution as predicted by consideration of circulation currents in rotating stars. Near the main sequence, rotational effects can reduce the moment of inertia of a star, so nonrotating models underestimate the expected velocities for evolving stars. On the red giant branch, angular momentum redistribution reduces the surface velocity by a factor of 2 or more, relative to the velocity expected for no radial redistribution. This removes the discrepancy between predicted and observed rotation rates for the K giants and makes it unlikely that these stars lose significant amounts of angular momentum by stellar winds. Calculations indicate that improved observations of the red giants in the Hyades cluster can be used to determine how angular momentum is redistributed by convection

Twinning of amphibian embryos by centrifugation

NASA Technical Reports Server (NTRS)

Black, S. D.

1984-01-01

In the frog Xenopus laevis, the dorsal structures of the embryonic body axis normally derive from the side of the egg opposite the side of sperm entry. However, if the uncleaved egg is inclined at lg or centrifuged in an inclined position, this topographic relationship is overridden: the egg makes its dorsal axial structures according to its orientation in the gravitational/centrifugal field, irrespective of the position of sperm entry. Certain conditions of centrifugation cause eggs to develop into conjoined twins with two sets of axial structures. A detailed analysis of twinning provided some insight into experimental axis orientation. First, as with single-axis embryos, both axes in twins are oriented according to the direction of centrifugation. One axis forms at the centripetal side of the egg and the other forms at the centrifugal side, even when the side of sperm entry is normal to the centrifugal force vector. Second, if eggs are centrifuged to give twins, but are inclined at lg to prevent post-centrifugation endoplasmic redistributions, only single-axis embryos develop. Thus, a second redistribution is required for high-frequency secondary axis formation. This can be accomplished by lg (as in the single centrifugations) or by a second centrifugation directed along the egg's animal-vegetal axis.

The distribution of evaporitic weathering products on Antarctic meteorites

NASA Technical Reports Server (NTRS)

Velbel, Michael A.

1987-01-01

White evaporite deposits of terrestrial origin occur on some 5 percent of Antarctic meteorites. The few previous studies, and new mineralogical analyses, indicate that the deposits are predominately carbonates and/or sulfates of magnesium. The distribution of white evaporitic salt deposits differs among different meteorite compositional groups and weathering categories. Salts occur with unusual frequency on carbonaceous chondrites, and are especially common in carbonaceous chondrites of weathering categories A and B. Among achondrites, weathering categories A and A/B show the most examples of salt weathering. Unlike carbonaceous chondrites and achrondites, most salt-bearing ordinary (H and L) chondrites are from rustier meteorites of weathering categories B, and to a lesser degree, B/C and C. The LL chondrites are conspicuous by their complete lack or any salt-weathering product. Almost two-thirds of all evaporite-bearing meteorites belong to weathering categories, A, A/B, and B. Where chemical and/or mineralogical data are available, there is a persistent suggestion that evaporite formation is accompanied by elemental redistribution from meteorite interiors. Meteorites of weathering categories B, A/B, and even A may have experienced significant element redistribution and/or contamination as a result of terrestrial exposure.

Cardio-chemical exchange saturation transfer magnetic resonance imaging reveals molecular signatures of endogenous fibrosis and exogenous contrast media.

PubMed

Vandsburger, Moriel; Vandoorne, Katrien; Oren, Roni; Leftin, Avigdor; Mpofu, Senzeni; Delli Castelli, Daniela; Aime, Silvio; Neeman, Michal

2015-01-01

Application of emerging molecular MRI techniques, including chemical exchange saturation transfer (CEST)-MRI, to cardiac imaging is desirable; however, conventional methods are poorly suited for cardiac imaging, particularly in small animals with rapid heart rates. We developed a CEST-encoded steady state and retrospectively gated cardiac cine imaging sequence in which the presence of fibrosis or paraCEST contrast agents was directly encoded into the steady-state myocardial signal intensity (cardioCEST). Development of cardioCEST: A CEST-encoded cardiac cine MRI sequence was implemented on a 9.4T small animal scanner. CardioCEST of fibrosis was serially performed by acquisition of a series of CEST-encoded cine images at multiple offset frequencies in mice (n=7) after surgically induced myocardial infarction. Scar formation was quantified using a spectral modeling approach and confirmed with histological staining. Separately, circulatory redistribution kinetics of the paramagnetic CEST agent Eu-HPDO3A were probed in mice using cardioCEST imaging, revealing rapid myocardial redistribution, and washout within 30 minutes (n=6). Manipulation of vascular tone resulted in heightened peak CEST contrast in the heart, but did not alter redistribution kinetics (n=6). At 28 days after myocardial infarction (n=3), CEST contrast kinetics in infarct zone tissue were altered, demonstrating gradual accumulation of Eu-HPDO3A in the increased extracellular space. cardioCEST MRI enables in vivo imaging of myocardial fibrosis using endogenous contrast mechanisms, and of exogenously delivered paraCEST agents, and can enable multiplexed imaging of multiple molecular targets at high-resolution coupled with conventional cardiac MRI scans. © 2013 American Heart Association, Inc.

47 CFR 76.1909 - Redistribution control of unencrypted digital terrestrial broadcast content.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 4 2010-10-01 2010-10-01 false Redistribution control of unencrypted digital... Redistribution control of unencrypted digital terrestrial broadcast content. (a) For the purposes of this section, the terms unencrypted digital terrestrial broadcast content, EIT, PMT, broadcast flag, covered...

7 CFR 247.24 - Recovery and redistribution of caseload and administrative funds.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 4 2010-01-01 2010-01-01 false Recovery and redistribution of caseload and...) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE CHILD NUTRITION PROGRAMS COMMODITY SUPPLEMENTAL FOOD PROGRAM § 247.24 Recovery and redistribution of caseload and administrative funds. (a) May FNS...

Redistribution on the thallium scan in myocardial sarcoidosis: concise communication

DOE Office of Scientific and Technical Information (OSTI.GOV)

Makler, P.T.; Lavine, S.J.; Denenberg, B.S.

1981-05-01

Resting and redistribution thallium studies were performed in four young patients with sarcoidosis to evaluate the possibility of myocardial involvement. In each case the resting scan showed marked defects that resolved on the redistribution studies. In a different patient population, these results would have implied significant coronary artery disease.

45 CFR 98.64 - Reallotment and redistribution of funds.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 45 Public Welfare 1 2012-10-01 2012-10-01 false Reallotment and redistribution of funds. 98.64 Section 98.64 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION CHILD CARE AND DEVELOPMENT FUND Financial Management § 98.64 Reallotment and redistribution of funds. (a) According to the...

45 CFR 98.64 - Reallotment and redistribution of funds.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 45 Public Welfare 1 2010-10-01 2010-10-01 false Reallotment and redistribution of funds. 98.64 Section 98.64 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION CHILD CARE AND DEVELOPMENT FUND Financial Management § 98.64 Reallotment and redistribution of funds. (a) According to the...

45 CFR 98.64 - Reallotment and redistribution of funds.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 45 Public Welfare 1 2013-10-01 2013-10-01 false Reallotment and redistribution of funds. 98.64 Section 98.64 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION CHILD CARE AND DEVELOPMENT FUND Financial Management § 98.64 Reallotment and redistribution of funds. (a) According to the...

The purple cauliflower arises from activation of a MYB transcription factor.

PubMed

Chiu, Li-Wei; Zhou, Xiangjun; Burke, Sarah; Wu, Xianli; Prior, Ronald L; Li, Li

2010-11-01

Anthocyanins are responsible for the color of many flowers, fruits, and vegetables. An interesting and unique Purple (Pr) gene mutation in cauliflower (Brassica oleracea var botrytis) confers an abnormal pattern of anthocyanin accumulation, giving the striking mutant phenotype of intense purple color in curds and a few other tissues. To unravel the nature of the Pr mutation in cauliflower, we isolated the Pr gene via a combination of candidate gene analysis and fine mapping. Pr encoded a R2R3 MYB transcription factor that exhibited tissue-specific expression, consistent with an abnormal anthocyanin accumulation pattern in the mutant. Transgenic Arabidopsis (Arabidopsis thaliana) and cauliflower plants expressing the Pr-D allele recapitulated the mutant phenotype, confirming the isolation of the Pr gene. Up-regulation of Pr specifically activated a basic helix-loop-helix transcription factor and a subset of anthocyanin structural genes encoding flavonoid 3'-hydroxylase, dihydroflavonol 4-reductase, and leucoanthocyanidin dioxygenase to confer ectopic accumulation of pigments in the purple cauliflower. Our results indicate that the genetic variation including a Harbinger DNA transposon insertion in the upstream regulatory region of the Pr-D allele is responsible for the up-regulation of the Pr gene in inducing phenotypic change in the plant. The successful isolation of Pr provides important information on the regulatory control of anthocyanin biosynthesis in Brassica vegetables, and offers a genetic resource for development of new varieties with enhanced health-promoting properties and visual appeal.

The Purple Cauliflower Arises from Activation of a MYB Transcription Factor1[W][OA

PubMed Central

Chiu, Li-Wei; Zhou, Xiangjun; Burke, Sarah; Wu, Xianli; Prior, Ronald L.; Li, Li

2010-01-01

Anthocyanins are responsible for the color of many flowers, fruits, and vegetables. An interesting and unique Purple (Pr) gene mutation in cauliflower (Brassica oleracea var botrytis) confers an abnormal pattern of anthocyanin accumulation, giving the striking mutant phenotype of intense purple color in curds and a few other tissues. To unravel the nature of the Pr mutation in cauliflower, we isolated the Pr gene via a combination of candidate gene analysis and fine mapping. Pr encoded a R2R3 MYB transcription factor that exhibited tissue-specific expression, consistent with an abnormal anthocyanin accumulation pattern in the mutant. Transgenic Arabidopsis (Arabidopsis thaliana) and cauliflower plants expressing the Pr-D allele recapitulated the mutant phenotype, confirming the isolation of the Pr gene. Up-regulation of Pr specifically activated a basic helix-loop-helix transcription factor and a subset of anthocyanin structural genes encoding flavonoid 3’-hydroxylase, dihydroflavonol 4-reductase, and leucoanthocyanidin dioxygenase to confer ectopic accumulation of pigments in the purple cauliflower. Our results indicate that the genetic variation including a Harbinger DNA transposon insertion in the upstream regulatory region of the Pr-D allele is responsible for the up-regulation of the Pr gene in inducing phenotypic change in the plant. The successful isolation of Pr provides important information on the regulatory control of anthocyanin biosynthesis in Brassica vegetables, and offers a genetic resource for development of new varieties with enhanced health-promoting properties and visual appeal. PMID:20855520

Progress report 3 of cooperative program for design, fabrication, and testing of high modulus composite helicopter shafting

NASA Technical Reports Server (NTRS)

Wright, C. C.; Baker, D. J.

1980-01-01

This report describes the third phase of work, the objective of which was to overcome the excessive brittleness of the previously developed UH-1 helicopter tail rotor drive shaft design which demonstrated a shaft train weight savings of 53.1% over the current 2024-T3 aluminum shaft train. A materials impact program demonstrated exceptionally noteworthy performance of two woven constructions containing E-glass and PRD 49-III (designation later changed to KEVLAR 49) fibers in an epoxy resin matrix. Thermoplastic matrices and PRD 49-III fiber provided impact resistance at low weight which was superior to composites having the same fiber in a thermoset resin matrix. A design, fabrication, and test program showed that shaft impact resistance could be improved over the previously developed graphite composite design at a cost in shaft train rate savings. The shaft train weight savings of the most impact tolerant construction was 4.0% over the current aluminum shaft train. Alternating plies of graphite and glass appear to provide substantially greater tube impact durability than that provided by hybridization of the two fibers into one tape wound to a ply design equivalent in strength and stiffness to that of the alternating ply design. Recommendations were made to continue research work to exploit the potential for more impact-durable structures through the use of KEVLAR 49 fiber, woven structures, thermoplastic matrices and THORNEL 50-S/KEVLAR 49 blends with thermoset matrices.

Lune/eye gone, a Pax-like protein, uses a partial paired domain and a homeodomain for DNA recognition.

PubMed

Jun, S; Wallen, R V; Goriely, A; Kalionis, B; Desplan, C

1998-11-10

Pax proteins, characterized by the presence of a paired domain, play key regulatory roles during development. The paired domain is a bipartite DNA-binding domain that contains two helix-turn-helix domains joined by a linker region. Each of the subdomains, the PAI and RED domains, has been shown to be a distinct DNA-binding domain. The PAI domain is the most critical, but in specific circumstances, the RED domain is involved in DNA recognition. We describe a Pax protein, originally called Lune, that is the product of the Drosophila eye gone gene (eyg). It is unique among Pax proteins, because it contains only the RED domain. eyg seems to play a role both in the organogenesis of the salivary gland during embryogenesis and in the development of the eye. A high-affinity binding site for the Eyg RED domain was identified by using systematic evolution of ligands by exponential enrichment techniques. This binding site is related to a binding site previously identified for the RED domain of the Pax-6 5a isoform. Eyg also contains another DNA-binding domain, a Prd-class homeodomain (HD), whose palindromic binding site is similar to other Prd-class HDs. The ability of Pax proteins to use the PAI, RED, and HD, or combinations thereof, may be one mechanism that allows them to be used at different stages of development to regulate various developmental processes through the activation of specific target genes.

Lune/eye gone, a Pax-like protein, uses a partial paired domain and a homeodomain for DNA recognition

PubMed Central

Jun, Susie; Wallen, Robert V.; Goriely, Anne; Kalionis, Bill; Desplan, Claude

1998-01-01

Pax proteins, characterized by the presence of a paired domain, play key regulatory roles during development. The paired domain is a bipartite DNA-binding domain that contains two helix–turn–helix domains joined by a linker region. Each of the subdomains, the PAI and RED domains, has been shown to be a distinct DNA-binding domain. The PAI domain is the most critical, but in specific circumstances, the RED domain is involved in DNA recognition. We describe a Pax protein, originally called Lune, that is the product of the Drosophila eye gone gene (eyg). It is unique among Pax proteins, because it contains only the RED domain. eyg seems to play a role both in the organogenesis of the salivary gland during embryogenesis and in the development of the eye. A high-affinity binding site for the Eyg RED domain was identified by using systematic evolution of ligands by exponential enrichment techniques. This binding site is related to a binding site previously identified for the RED domain of the Pax-6 5a isoform. Eyg also contains another DNA-binding domain, a Prd-class homeodomain (HD), whose palindromic binding site is similar to other Prd-class HDs. The ability of Pax proteins to use the PAI, RED, and HD, or combinations thereof, may be one mechanism that allows them to be used at different stages of development to regulate various developmental processes through the activation of specific target genes. PMID:9811867

Spatial-temporal Change of Sanshui district's Dike-pond from 1979-2009

NASA Astrophysics Data System (ADS)

Liu, Jiaxing; Chen, Jianfei; Wang, Xiaoxuan

Dike-pond is a representative style of ecological agriculture in the PRD(Pearl River Delta). Since 1992, Guangdong quicken its pace of reform and opening-up to the outside world. A mass of factories had been built in the PRD. The dike-ponds have come across some influential changes in the recent 30 years. To detect and study on the changes of dike-ponds, the Remote Sensing and Geography Information System skill was applied in this paper. This article selected Sanshui district as an example and used Landsat TM 1979, 1990, 2000 and SPOT 2009 satellite image as the major data sources. With the help of ITTVIS company newly released software-ENVI EX, object-oriented approach has been used to extract the dike-pond land from each image. The result indicates that the area of dike-pond gained rapidly growth from 1979 to 2000, but decrease critically during 2000-2009. When using Change Detection Analysis to compute each period's change statistics, the result shown that the increased dike-pond area were mainly from vegetation covered land and other bare land. Then we found out that the mean centre of Sanshui district's dike-pond was moving from northwest to southeast during 1979-2009. Therefore, it comes to the conclusion that Sanshui district's dike-pond increased across the southeast of Sanshui district from 1979 to 2009. Last but not least, some suggestions have been put forward to keep the dike-pond land area from decreasing.

Ground-level ozone pollution and its health impacts in China

NASA Astrophysics Data System (ADS)

Liu, Huan; Liu, Shuai; Xue, Boru; Lv, Zhaofeng; Meng, Zhihang; Yang, Xiaofan; Xue, Tao; Yu, Qiao; He, Kebin

2018-01-01

In recent years, ground-level ozone pollution in China has become an increasingly prominent problem. This study simulated and analyzed spatiotemporal distribution of ozone and exposure level by the Weather Research and Forecasting (WRF)-Community Multiscale Air Quality (CMAQ) models and monitoring data from 1516 national air quality monitoring stations in China during 2015. The simulation results show that the Sichuan Basin, Shandong, Shanxi, Henan, Anhui, Qinghai-Tibetan Plateau, Yangtze River Delta (YRD), Pearl River Delta (PRD) and Beijing-Tianjin-Hebei (BTH) region had relatively high average annual concentrations of ozone. The regions with more than 10% nonattainment days of 160 μg/m3 (daily maximum 8-h) are mainly concentrated in BTH, Shandong Peninsula and YRD, where large seasonal variations were also found. Exposure levels were calculated based on population data and simulated ozone concentrations. The cumulative population exposed to daily maximum 8-h concentration greater than or equal to 100 μg/m3 was 816.04 million, 61.17% of the total. Three methods were used to estimate the mortality of chronic obstructive pulmonary disease (COPD) attributable to ozone. A comparative study using different exposure concentrations and threshold concentrations found large variations among these methods, although they were all peer-reviewed methods. The estimated mortality of COPD caused by ozone in China in 2015 ranged from 55341 to 80280, which mainly distributed in Beijing, Shandong, Henan, Hubei and Sichuan Province, the YRD and PRD region.

The New Antimicrobial Peptide SpHyastatin from the Mud Crab Scylla paramamosain with Multiple Antimicrobial Mechanisms and High Effect on Bacterial Infection

PubMed Central

Shan, Zhongguo; Zhu, Kexin; Peng, Hui; Chen, Bei; Liu, Jie; Chen, Fangyi; Ma, Xiaowan; Wang, Shuping; Qiao, Kun; Wang, Kejian

2016-01-01

SpHyastatin was first identified as a new cationic antimicrobial peptide in hemocytes of the mud crab Scylla paramamosain. Based on the amino acid sequences deduced, it was predicted that this peptide was composed of two different functional domains, a proline-rich domain (PRD) and a cysteine-rich domain (CRD). The recombinant product of SpHyastatin displayed potent antimicrobial activities against the human pathogen Staphylococcus aureus and the aquatic animal pathogens Aeromonas hydrophila and Pseudomonas fluorescens. Compared with the CRD of SpHyastatin, the PRD presented better antimicrobial and chitin binding activities, but both regions were essential for allowing SpHyastatin complete antimicrobial activity. The binding properties of SpHyastatin to different microbial surface molecules suggested that this might be an initial and crucial step for performing its antimicrobial activities. Evaluated using propidium iodide uptake assays and scanning electron microscopy images, the antimicrobial mechanism of SpHyastatin was found to be prone to disrupt cell membrane integrity. Interestingly, SpHyastatin exerted its role specifically on the surface of S. aureus and Pichia pastoris whereas it directly killed P. fluorescens through simultaneous targeting the membrane and the cytoplasm, indicating that SpHyastatin could use different antimicrobial mechanisms to kill different species of microbes. As expected, the recombinant SpHyastatin increased the survival rate of crabs challenged with Vibrio parahaemolyticus. In addition, SpHyastatin could modulate some V. parahaemolyticus-responsive genes in S. paramamosain. PMID:27493644

More frequent flooding? Changes in flood frequency in the Pearl River basin, China, since 1951 and over the past 1000 years

NASA Astrophysics Data System (ADS)

Zhang, Qiang; Gu, Xihui; Singh, Vijay P.; Shi, Peijun; Sun, Peng

2018-05-01

Flood risks across the Pearl River basin, China, were evaluated using a peak flood flow dataset covering a period of 1951-2014 from 78 stations and historical flood records of the past 1000 years. The generalized extreme value (GEV) model and the kernel estimation method were used to evaluate frequencies and risks of hazardous flood events. Results indicated that (1) no abrupt changes or significant trends could be detected in peak flood flow series at most of the stations, and only 16 out of 78 stations exhibited significant peak flood flow changes with change points around 1990. Peak flood flow in the West River basin increased and significant increasing trends were identified during 1981-2010; decreasing peak flood flow was found in coastal regions and significant trends were observed during 1951-2014 and 1966-2014. (2) The largest three flood events were found to cluster in both space and time. Generally, basin-scale flood hazards can be expected in the West and North River basins. (3) The occurrence rate of floods increased in the middle Pearl River basin but decreased in the lower Pearl River basin. However, hazardous flood events were observed in the middle and lower Pearl River basin, and this is particularly true for the past 100 years. However, precipitation extremes were subject to moderate variations and human activities, such as building of levees, channelization of river systems, and rapid urbanization; these were the factors behind the amplification of floods in the middle and lower Pearl River basin, posing serious challenges for developing measures of mitigation of flood hazards in the lower Pearl River basin, particularly the Pearl River Delta (PRD) region.

Soil quality and water redistribution influences on plant production over low hillslopes on reclaimed mined land

USDA-ARS?s Scientific Manuscript database

A basic part of soils’ delivery of ecosystem services is the interaction between plant growth response to soil quality (SQ) factors at point scale and water redistribution effects at hillslope scale. To study the influence of SQ-indicator properties and water redistribution, we examined hillslope pr...

7 CFR 247.24 - Recovery and redistribution of caseload and administrative funds.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 4 2013-01-01 2013-01-01 false Recovery and redistribution of caseload and... FOOD PROGRAM § 247.24 Recovery and redistribution of caseload and administrative funds. (a) May FNS... agency must use 95 percent of its original caseload allocation to be eligible for additional caseload...

7 CFR 247.24 - Recovery and redistribution of caseload and administrative funds.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 4 2014-01-01 2014-01-01 false Recovery and redistribution of caseload and... FOOD PROGRAM § 247.24 Recovery and redistribution of caseload and administrative funds. (a) May FNS... agency must use 95 percent of its original caseload allocation to be eligible for additional caseload...

7 CFR 247.24 - Recovery and redistribution of caseload and administrative funds.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 4 2012-01-01 2012-01-01 false Recovery and redistribution of caseload and... FOOD PROGRAM § 247.24 Recovery and redistribution of caseload and administrative funds. (a) May FNS... agency must use 95 percent of its original caseload allocation to be eligible for additional caseload...

Development Planning and Population Growth and Redistribution in the Republic of Iraq.

ERIC Educational Resources Information Center

El Attar, M. E.; Salman, A. D.

Utilizing the 1947, 1957, and l965 census data and the 1970 preliminary population count, the relationship between population growth and redistribution and development planning in Iraq was examined. Trends in rural-urban population growth, migration, and population redistribution were examined as they pertained to the socioeconomic development…

Overload cascading failure on complex networks with heterogeneous load redistribution

NASA Astrophysics Data System (ADS)

Hou, Yueyi; Xing, Xiaoyun; Li, Menghui; Zeng, An; Wang, Yougui

2017-09-01

Many real systems including the Internet, power-grid and financial networks experience rare but large overload cascading failures triggered by small initial shocks. Many models on complex networks have been developed to investigate this phenomenon. Most of these models are based on the load redistribution process and assume that the load on a failed node shifts to nearby nodes in the networks either evenly or according to the load distribution rule before the cascade. Inspired by the fact that real power-grid tends to place the excess load on the nodes with high remaining capacities, we study a heterogeneous load redistribution mechanism in a simplified sandpile model in this paper. We find that weak heterogeneity in load redistribution can effectively mitigate the cascade while strong heterogeneity in load redistribution may even enlarge the size of the final failure. With a parameter θ to control the degree of the redistribution heterogeneity, we identify a rather robust optimal θ∗ = 1. Finally, we find that θ∗ tends to shift to a larger value if the initial sand distribution is homogeneous.

Incorporating convection into one-dimensional solute redistribution during crystal growth from the melt I. The steady-state solution

NASA Astrophysics Data System (ADS)

Yen, C. T.; Tiller, W. A.

1992-03-01

A one-dimensional mathematical analysis is made of the redistribution of solute which occurs during crystal growth from a convected melt. In this analysis, the important contribution from lateral melt convection to one-dimensional solute redistribution analysis is taken into consideration via an annihilation/creation term in the one-dimensional solute transport equation. Calculations of solute redistribution under steady-state conditions have been carried out analytically. It is found that this new solute redistribution model overcomes several weaknesses that occur when applying the Burton, Prim and Slichter solute segregation equation (1953) in real melt growth situations. It is also found that, with this correction, the diffusion coefficients for solute's in liquid silicon are now found to be in the same range as other liquid metal diffusion coefficients.

Potential biases in evapotranspiration estimates from Earth system models due to spatial heterogeneity and lateral moisture redistribution

NASA Astrophysics Data System (ADS)

Rouholahnejad, E.; Kirchner, J. W.

2016-12-01

Evapotranspiration (ET) is a key process in land-climate interactions and affects the dynamics of the atmosphere at local and regional scales. In estimating ET, most earth system models average over considerable sub-grid heterogeneity in land surface properties, precipitation (P), and potential evapotranspiration (PET). This spatial averaging could potentially bias ET estimates, due to the nonlinearities in the underlying relationships. In addition, most earth system models ignore lateral redistribution of water within and between grid cells, which could potentially alter both local and regional ET. Here we present a first attempt to quantify the effects of spatial heterogeneity and lateral redistribution on grid-cell-averaged ET as seen from the atmosphere over heterogeneous landscapes. Using a Budyko framework to express ET as a function of P and PET, we quantify how sub-grid heterogeneity affects average ET at the scale of typical earth system model grid cells. We show that averaging over sub-grid heterogeneity in P and PET, as typical earth system models do, leads to overestimates of average ET. We use a similar approach to quantify how lateral redistribution of water could affect average ET, as seen from the atmosphere. We show that where the aridity index P/PET increases with altitude, gravitationally driven lateral redistribution will increase average ET, implying that models that neglect lateral moisture redistribution will underestimate average ET. In contrast, where the aridity index P/PET decreases with altitude, gravitationally driven lateral redistribution will decrease average ET. This approach yields a simple conceptual framework and mathematical expressions for determining whether, and how much, spatial heterogeneity and lateral redistribution can affect regional ET fluxes as seen from the atmosphere. This analysis provides the basis for quantifying heterogeneity and redistribution effects on ET at regional and continental scales, which will be the focus of future work.

High frequency sound propagation in a network of interconnecting streets

NASA Astrophysics Data System (ADS)

Hewett, D. P.

2012-12-01

We propose a new model for the propagation of acoustic energy from a time-harmonic point source through a network of interconnecting streets in the high frequency regime, in which the wavelength is small compared to typical macro-lengthscales such as street widths/lengths and building heights. Our model, which is based on geometrical acoustics (ray theory), represents the acoustic power flow from the source along any pathway through the network as the integral of a power density over the launch angle of a ray emanating from the source, and takes into account the key phenomena involved in the propagation, namely energy loss by wall absorption, energy redistribution at junctions, and, in 3D, energy loss to the atmosphere. The model predicts strongly anisotropic decay away from the source, with the power flow decaying exponentially in the number of junctions from the source, except along the axial directions of the network, where the decay is algebraic.

Giant plasmonic mode splitting in THz metamaterials mediated by coupling with Lorentz phonon mode

NASA Astrophysics Data System (ADS)

Yu, Leilei; Huang, Yuanyuan; Liu, Changji; Hu, Fangrong; Jin, Yanping; Yan, Yi; Xu, Xinlong

2018-04-01

Giant plasmonic mode splitting has been observed in THz metamaterials due to the mediation by the Lorentz phonon dielectric material. This splitting mode is confirmed by the surface current distribution, indicating that plasmonic modes behave like dipole resonances, while the phonon mode behaves like multipole resonance due to coupling. The splitting of the plasmonic modes demonstrates an anti-crossing behavior with the change in Lorentz central frequency, which suggests that there is energy redistribution between plasmon and phonon modes. Similar to the Stark effect, the splitting frequency difference increases with the increasing direct current dielectric function. We also propose an interaction Hamiltonian to understand the physical mechanism of the plasmonic splitting. Furthermore, the splitting is convincible for small Lorentz dielectrics such as sugar and amino acid in the THz region, which could be used for biomolecular sensing applications.

Electrically and spatially controllable PDLC phase gratings for diffraction and modulation of laser beams

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hadjichristov, Georgi B., E-mail: georgibh@issp.bas.bg; Marinov, Yordan G.; Petrov, Alexander G.

2016-03-25

We present a study on electrically- and spatially-controllable laser beam diffraction, electrooptic (EO) phase modulation, as well as amplitude-frequency EO modulation by single-layer microscale polymer-dispersed liquid crystal (PDLC) phase gratings (PDLC SLPGs) of interest for device applications. PDLC SLPGs were produced from nematic liquid crystal (LC) E7 in photo-curable NOA65 polymer. The wedge-formed PDLC SLPGs have a continuously variable thickness (2–25 µm). They contain LC droplets of diameters twice as the layer thickness, with a linear-gradient size distribution along the wedge. By applying alternating-current (AC) electric field, the PDLC SLPGs produce efficient: (i) diffraction splitting of transmitted laser beams; (ii)more » spatial redistribution of diffracted light intensity; (iii) optical phase modulation; (iv) amplitude-frequency modulation, all controllable by the driven AC field and the droplet size gradient.« less

Redistributive effects in public health care financing.

PubMed

Honekamp, Ivonne; Possenriede, Daniel

2008-11-01

This article focuses on the redistributive effects of different measures to finance public health insurance. We analyse the implications of different financing options for public health insurance on the redistribution of income from good to bad health risks and from high-income to low-income individuals. The financing options considered are either income-related (namely income taxes, payroll taxes, and indirect taxes), health-related (co-insurance, deductibles, and no-claim), or neither (flat fee). We show that governments who treat access to health care as a basic right for everyone should consider redistributive effects when reforming health care financing.

Gentamicin differentially alters cellular metabolism of cochlear hair cells as revealed by NAD(P)H fluorescence lifetime imaging

NASA Astrophysics Data System (ADS)

Zholudeva, Lyandysha V.; Ward, Kristina G.; Nichols, Michael G.; Smith, Heather Jensen

2015-05-01

Aminoglycoside antibiotics are implicated as culprits of hearing loss in more than 120,000 individuals annually. Research has shown that the sensory cells, but not supporting cells, of the cochlea are readily damaged and/or lost after use of such antibiotics. High-frequency outer hair cells (OHCs) show a greater sensitivity to antibiotics than high- and low-frequency inner hair cells (IHCs). We hypothesize that variations in mitochondrial metabolism account for differences in susceptibility. Fluorescence lifetime microscopy was used to quantify changes in NAD(P)H in sensory and supporting cells from explanted murine cochleae exposed to mitochondrial uncouplers, inhibitors, and an ototoxic antibiotic, gentamicin (GM). Changes in metabolic state resulted in a redistribution of NAD(P)H between subcellular fluorescence lifetime pools. Supporting cells had a significantly longer lifetime than sensory cells. Pretreatment with GM increased NAD(P)H intensity in high-frequency sensory cells, as well as the NAD(P)H lifetime within IHCs. GM specifically increased NAD(P)H concentration in high-frequency OHCs, but not in IHCs or pillar cells. Variations in NAD(P)H intensity in response to mitochondrial toxins and GM were greatest in high-frequency OHCs. These results demonstrate that GM rapidly alters mitochondrial metabolism, differentially modulates cell metabolism, and provides evidence that GM-induced changes in metabolism are significant and greatest in high-frequency OHCs.

Gentamicin differentially alters cellular metabolism of cochlear hair cells as revealed by NAD(P)H fluorescence lifetime imaging

PubMed Central

Zholudeva, Lyandysha V.; Ward, Kristina G.; Nichols, Michael G.; Smith, Heather Jensen

2015-01-01

Abstract. Aminoglycoside antibiotics are implicated as culprits of hearing loss in more than 120,000 individuals annually. Research has shown that the sensory cells, but not supporting cells, of the cochlea are readily damaged and/or lost after use of such antibiotics. High-frequency outer hair cells (OHCs) show a greater sensitivity to antibiotics than high- and low-frequency inner hair cells (IHCs). We hypothesize that variations in mitochondrial metabolism account for differences in susceptibility. Fluorescence lifetime microscopy was used to quantify changes in NAD(P)H in sensory and supporting cells from explanted murine cochleae exposed to mitochondrial uncouplers, inhibitors, and an ototoxic antibiotic, gentamicin (GM). Changes in metabolic state resulted in a redistribution of NAD(P)H between subcellular fluorescence lifetime pools. Supporting cells had a significantly longer lifetime than sensory cells. Pretreatment with GM increased NAD(P)H intensity in high-frequency sensory cells, as well as the NAD(P)H lifetime within IHCs. GM specifically increased NAD(P)H concentration in high-frequency OHCs, but not in IHCs or pillar cells. Variations in NAD(P)H intensity in response to mitochondrial toxins and GM were greatest in high-frequency OHCs. These results demonstrate that GM rapidly alters mitochondrial metabolism, differentially modulates cell metabolism, and provides evidence that GM-induced changes in metabolism are significant and greatest in high-frequency OHCs. PMID:25688541

Redistribution kinetics of Ga and Al substitutions in yttrium iron garnet

NASA Astrophysics Data System (ADS)

Röschmann, P.

1980-01-01

Results are presented for the octahedral-tetrahedral site redistribution rate of Ga or Al and Fe in YIG in the temperature range 773 to 1523 K. The activation energy for the cation transfer decreases with increasing the oxygen vacancy concentration by annealing. A screening model describes qualitatively the effects of enhanced cation redistribution.

Hydraulic redistribution in a Douglas-fir forest: lessons from system manipulations.

Treesearch

J. Renée Brooks; Frederick C. Meinzer; Jeffery M. Warren; Jean-Christophe Domec; Rob Coulombe

2006-01-01

Hydraulic redistribution (HR) occurs in many ecosystems; however, key questions remain about its consequences at the ecosystem level. The objectives of the present study were to quantify seasonal variation in HR and its driving force, and to manipulate the soil-root system to elucidate physiological components controlling HR and utilization of redistributed water. In...

Redistributing Wealth to Families: The Advantages of the MYRIADE Model

ERIC Educational Resources Information Center

Legendre, Francois; Lorgnet, Jean-Paul; Thibault, Florence

2005-01-01

This study aims to shed light on the main characteristics of the French system for redistributing wealth to families through tax revenues and social transfers. For the purposes of this exercise, the authors used the MYRIADE microsimulation model, which covers most of the redistribution system, though it is limited to monetary flows such as family…

Use of anthropogenic radioisotopes to estimate rates of soil redistribution by wind II: The potential for future use of 239+240Pu

NASA Astrophysics Data System (ADS)

Van Pelt, R. Scott; Ketterer, Michael E.

2013-06-01

In the previous paper, the use of soilborne 137Cs from atmospheric fallout to estimate rates of soil redistribution, particularly by wind, was reviewed. This method relies on the assumption that the source of 137Cs in the soil profile is from atmospheric fallout following the period of atmospheric weapons testing so that the temporal and, to a certain extent, the spatial patterns of 137Cs deposition are known. One of the major limitations occurs when local or regional sources of 137Cs contamination mask the pulse from global fallout, making temporal estimates of redistribution difficult or impossible. Like 137Cs, Pu exhibits strong affinity for binding to soil particle surfaces, and therefore, re-distribution of Pu inventory indicates inferred soil re-distribution. Compared to 137Cs, 239Pu and 240Pu offer several important advantages: (a) the two major Pu isotopes have much longer half-lives than 137Cs and (b) the ratio 240Pu/239Pu is used to examine whether the Pu is from stratospheric fallout. In this paper, we review the literature concerning Pu in soil and of current attempts to use this tracer to estimate rates of soil redistribution. We also present preliminary, unpublished data from a pilot study designed to test whether or not 239+240Pu can be used to estimate rates of soil redistribution by wind. Based on similarities of profile distribution and relative inventories between 137Cs measurements and 239+240Pu measurements of split samples from a series of fields with documented wind erosion histories, we conclude that 239+240Pu may well be the anthropogenic radioisotope of choice for future soil redistribution investigations.

Sequence of Key Events in Shoot Gravitropism 1

PubMed Central

Migliaccio, Fernando; Rayle, David L.

1984-01-01

It has recently been shown that asymmetric acid efflux is closely correlated with the gravitropic curvature of plant shoots and roots. The research reported here addresses whether auxin (IAA) redistribution in shoots is the cause or result of asymmetric acid efflux. When abraded sunflower (Helianthus annuus cv Mammoth) hypocotyls are submerged in 20 millimolar neutral buffer, gravicurvature is greatly retarded relative to 0.2 millimolar controls. Nevertheless, in both buffer systems there is a similar redistribution of [3H]IAA toward the lower surface of gravistimulated sunflower hypocotyls. These results suggest that graviperception initiates IAA redistribution, which in turn results in auxin-induced asymmetric H+ efflux across the shoot. This interpretation is reinforced by data showing the effects of removal of the epidermal layers (peeling), osmotic shock, and morphactin treatment on gravicurvature and [3H]IAA redistribution. Peeling and osmotic shock inhibit gravicurvature but not redistribution. Morphactin inhibits both processes but does not inhibit hypocotyl straight growth. PMID:16663606

Fluctuation Reduction in a Si Micromechanical Resonator Tuned to Nonlinear Internal Resonance

NASA Astrophysics Data System (ADS)

Strachan, B. Scott; Czaplewski, David; Chen, Changyao; Dykman, Mark; Lopez, Daniel; Shaw, Steven

2015-03-01

We describe experimental and theoretical results on an unusual behavior of fluctuations when the system exhibits internal resonance. We study the fundamental flexural mode (FFM) of a Si microbeam. The FFM is electrically actuated and detected. It is resonantly nonlinearly coupled to another mode, which is not directly accessible and has a frequency nearly three times the FFM frequency. Both the FFM and the passive mode have long lifetimes. We find that the passive mode can be a ``sink'' for fluctuations of the FFM. This explains the recently observed dramatic decrease of these fluctuations at nonlinear resonance. The re-distribution of the vibration amplitudes and the fluctuations is reminiscent of what happens at level anti-crossing in quantum mechanics. However, here it is different because of interplay of the dependence of the vibration frequency of the FFM on its amplitude due to internal nonlinearity and the nonlinear resonance with the passive mode. We study both the response of the system to external resonant driving and also the behavior of the system in the presence of a feedback loop. The experimental and theoretical results are in good agreement.

Role of Terahertz (THz) Fluctuations in the Allosteric Properties of the PDZ Domains.

PubMed

Conti Nibali, Valeria; Morra, Giulia; Havenith, Martina; Colombo, Giorgio

2017-11-09

With the aim of investigating the relationship between the fast fluctuations of proteins and their allosteric behavior, we perform molecular dynamics simulations of two model PDZ domains with differential allosteric responses. We focus on protein dynamics in the THz regime (0.1-3 THz) as opposed to lower frequencies. By characterizing the dynamic modulation of the protein backbone induced by ligand binding in terms of single residue and pairwise distance fluctuations, we identify a response nucleus modulated by the ligand that is visible only at THz frequencies. The residues of this nucleus undergo a significant stiffening and an increase in mutual coordination upon binding. Additionally, we find that the dynamic modulation is significantly more intense for the side chains, where it is also redistributed to distal regions not immediately in contact with the ligand allowing us to better define the response nucleus at THz frequencies. The overlap between the known allosterically responding residues of the investigated PDZ domains and the modulated region highlighted here suggests that fast THz dynamics could play a role in allosteric mechanisms.

Knowing One's Lot in Life versus Climbing the Social Ladder: The Formation of Redistributive Preferences in Urban China

ERIC Educational Resources Information Center

Smyth, Russell; Mishra, Vinod; Qian, Xiaolei

2010-01-01

This paper examines, how individual preferences for redistribution in general and redistribution to improve access to education, improve social protection for the poor, reduce income inequality and reduce unemployment depend on beliefs about what determines one's lot in life and self-assessed prospects for climbing the social ladder in urban…

Inequality and Redistribution Policy Issues: Principles and Swedish Experience; Comment on Lindbeck's Paper [and] Discussion Paper.

ERIC Educational Resources Information Center

Lindbeck, Assar

Alternative methods of redistribution policy in mixed economies are compared in this paper. The paper deals with the objectives, methods, and problems in redistribution policy. The chief objective is to highlight principles and general problems, drawing heavily on the experiences of Sweden. This country is chosen as a case study since attempts to…

Effect of resonance frequency, power input, and saturation gas type on the oxidation efficiency of an ultrasound horn.

PubMed

Rooze, Joost; Rebrov, Evgeny V; Schouten, Jaap C; Keurentjes, Jos T F

2011-01-01

The sonochemical oxidation efficiency (η(ox)) of a commercial titanium alloy ultrasound horn has been measured using potassium iodide as a dosimeter at its main resonance frequency (20 kHz) and two higher resonance frequencies (41 and 62 kHz). Narrow power and frequency ranges have been chosen to minimise secondary effects such as changing bubble stability, and time available for radical diffusion from the bubble to the liquid. The oxidation efficiency, η(ox), is proportional to the frequency and to the power transmitted to the liquid (275 mL) in the applied power range (1-6 W) under argon. Luminol radical visualisation measurements show that the radical generation rate increases and a redistribution of radical producing zones is achieved at increasing frequency. Argon, helium, air, nitrogen, oxygen, and carbon dioxide have been used as saturation gases in potassium iodide oxidation experiments. The highest η(ox) has been observed at 5 W under air at 62 kHz. The presence of carbon dioxide in air gives enhanced nucleation at 41 and 62 kHz and has a strong influence on η(ox). This is supported by the luminol images, the measured dependence of η(ox) on input power, and bubble images recorded under carbon dioxide. The results give insight into the interplay between saturation gas and frequency, nucleation, and their effect on η(ox). Copyright © 2010 Elsevier B.V. All rights reserved.

Domain wall conductivity in KTiOPO4 crystals

NASA Astrophysics Data System (ADS)

Lindgren, G.; Canalias, C.

2017-07-01

We study the local ionic conductivity of ferroelectric domain walls and domains in KTiOPO4 single-crystals. We show a fourfold increase in conductivity at the domain walls, compared to that of the domains, attributed to an increased concentration of defects. Our current-voltage measurements reveal memristive-like behavior associated with topographic changes and permanent charge displacement. This behavior is observed for all the voltage sweep-rates at the domain walls, while it only occurs for low frequencies at the domains. We attribute these findings to the redistribution of ions due to the applied bias and their effect on the tip-sample barrier.

Modeling Microgravity Induced Fluid Redistribution Autoregulatory and Hydrostatic Enhancements

NASA Technical Reports Server (NTRS)

Myers, J. G.; Werner, C.; Nelson, E. S.; Feola, A.; Raykin, J.; Samuels, B.; Ethier, C. R.

2017-01-01

Space flight induces a marked cephalad (headward) redistribution of blood and interstitial fluid potentially resulting in a loss of venous tone and reduction in heart muscle efficiency upon introduction into the microgravity environment. Using various types of computational models, we are investigating how this fluid redistribution may induce intracranial pressure changes, relevant to reported reductions in astronaut visual acuity, part of the Visual Impairment and Intracranial Pressure (VIIP) syndrome. Methods: We utilize a lumped parameter cardiovascular system (CVS) model, augmented by compartments comprising the cerebral spinal fluid (CSF) space, as the primary tool to describe how microgravity, and the associated lack of hydrostatic gradient, impacts fluid redistribution. Models of ocular fluid pressures and biomechanics then accept the output of the above model as boundary condition input to allow more detailed, local analysis (see IWS Abstract by Ethier et al.). Recently, we enhanced the capabilities our previously reported CVS model through the implementation of robust autoregulatory mechanisms and a more fundamental approach to the implementation of hydrostatic mechanisms. Modifying the approach of Blanco et al., we implemented auto-regulation in a quasi-static manner, as an averaged effect across the span of one heartbeat. This approach reduced the higher frequency perturbations from the regulatory mechanism and was intended to allow longer simulation times (days) than models that implement within-beat regulatory mechanisms (minutes). A more fundamental approach to hydrostatics was implemented by a quasi-1D approach, in which compartment descriptions include compartment length, orientation and relative position, allowed for modeling of body orientation, relative body positioning and, in the future, alternative gravity environments. At this time the inclusion of hydrostatic mechanisms supplies additional capabilities to train and validate the CVS model with terrestrial data. Results and Conclusions: With the implementation of auto-regulation and hydrostatic modeling capabilities, the model performs as expected in the maintaining the CA (Central Artery) compartment pressure when simulating orientations ranging from supine to standing. The model appears to generally overpredict heart rate and thus cardiac output, possibly indicating sensitivity to the nominal heart rate, which is used as an initial set point of the regulation mechanisms. Despite this sensitivity, the model performs consistently for many hours of simulation time, indicating the success of our quasi-static implementation approach.

Internally mixed sea salt, soot, and sulfates at Macao, a coastal city in South China.

PubMed

Li, Weijun; Shao, Longyi; Shen, Rongrong; Yang, Shusheng; Wang, Zhishi; Tang, Uwa

2011-11-01

Direct observation of the mixing state of aerosol particles in a coastal urban city is critical to understand atmospheric processing and hygroscopic growth in humid air. Morphology, composition, and mixing state of individual aerosol particles from Macao, located south of the Pearl River Delta (PRD) and 100 km west of Hong Kong, were investigated using scanning electron microscopy (SEM) and transmission electron microscopy coupled with energy-dispersive X-ray spectrometry (TEM/EDX). SEM images show that soot and roughly spherical particles are prevalent in the samples. Based on the compositions of individual aerosol particles, aerosol particles with roughly spherical shape are classified into coarse Na-rich and fine S-rich particles. TEM/EDX indicates that each Na-rich particle consists of a Na-S core and NaNO3 shell. Even in the absence of heavy pollution, the marine sea salt particles were completely depleted in chloride, and Na-related sulfates and nitrates were enriched in Macao air. The reason could be that SO2 from the polluted PRD and ships in the South China Sea and NO2 from vehicles in the city sped up the chlorine depletion in sea salt through heterogeneous reactions. Fresh soot particles from vehicular emissions mainly occur near curbside. However, there are many aged soot particles in the sampling site surrounded by main roads 200 to 400 m away, suggesting that the fresh soot likely underwent a quick aging. Overall, secondary nitrates and sulfates internally mixed with soot and sea salt particles can totally change their surface hygroscopicity in coastal cities.

Source contributions to PM2.5 in Guangdong province, China by numerical modeling: Results and implications

NASA Astrophysics Data System (ADS)

Yin, Xiaohong; Huang, Zhijiong; Zheng, Junyu; Yuan, Zibing; Zhu, Wenbo; Huang, Xiaobo; Chen, Duohong

2017-04-01

As one of the most populous and developed provinces in China, Guangdong province (GD) has been experiencing regional haze problems. Identification of source contributions to ambient PM2.5 level is essential for developing effective control strategies. In this study, using the most up-to-date emission inventory and validated numerical model, source contributions to ambient PM2.5 from eight emission source sectors (agriculture, biogenic, dust, industry, power plant, residential, mobile and others) in GD in 2012 were quantified. Results showed that mobile sources are the dominant contributors to the ambient PM2.5 (24.0%) in the Pearl River Delta (PRD) region, the central and most developed area of GD, while industry sources are the major contributors (21.5% 23.6%) to those in the Northeastern GD (NE-GD) region and the Southwestern GD (SW-GD) region. Although many industries have been encouraged to move from the central GD to peripheral areas such as NE-GD and SW-GD, their emissions still have an important impact on the PM2.5 level in the PRD. In addition, agriculture sources are responsible for 17.5% to ambient PM2.5 in GD, indicating the importance of regulations on agricultural activities, which has been largely ignored in the current air quality management. Super-regional contributions were also quantified and their contributions to the ambient PM2.5 in GD are significant with notable seasonal differences. But they might be overestimated and further studies are needed to better quantify the transport impacts.

Process Analysis of Typhoon Related Ozone Pollution over the Pearl River Delta during the PRIDE-PRD2006

NASA Astrophysics Data System (ADS)

Li, Y.; Wang, X.; Zhang, Y.

2014-12-01

There were two typhoon processes during Campaign PRIDE-PRD2006 in July 2006 and serious ozone pollution episodes occurred before the landing of the typhoons. Chemical transport model CMAQ was employed in this work to simulate the ozone pollution episode related by the typhoon KAEMI. According to the meteorological conditions, the pollution episode could be divided into three phases with the movement of the typhoon, which were (1) far away from the continent; (2) coming close to the continent; (3) before landing. Process analysis was applied to get the contributions of physical and chemical processes for the ozone. It revealed that transport process was dominant during this pollution episode, and the influence of chemical process increased in the second phase. Three typical regions, northern rural area, urban area and Hong Kong area, were selected to study the contribution of each chemical and physical process. In the first phase, the primary process in northern rural area and the urban area was vertical diffusion, accounting for 47% and 46% respectively. In the second phase, the primary process in northern rural area and the urban area was chemical process, accounting for 33% and 31% respectively. In the third phase, the region of high concentration ozone moved southward. For Hong Kong area, the western inflow was prominent as 40%. Sensitivity study showed that urban areas were VOCs-limited regime with decreased ozone concentration when reducing the emission of VOCs. On the contrary, the ozone concentration in downwind rural areas decreased with the reduction of NOx, and the reason may be the decrement of the accumulated precursors.

Process analysis of regional aerosol pollution during spring in the Pearl River Delta region, China

NASA Astrophysics Data System (ADS)

Fan, Qi; Lan, Jing; Liu, Yiming; Wang, Xuemei; Chan, Pakwai; Hong, Yingying; Feng, Yerong; Liu, Yexin; Zeng, Yanjun; Liang, Guixiong

2015-12-01

A numerical simulation analysis was performed for three air pollution episodes in the Pearl River Delta (PRD) region during March 2012 using the third-generation air quality modeling system Models-3/CMAQ. The results demonstrated that particulate matter was the primary pollutant for all three pollution episodes and was accompanied by relatively low visibility in the first two episodes. Weather maps indicate that the first two episodes occurred under the influence of warm, wet southerly air flow systems that led to high humidity throughout the region. The liquid phase reaction of gaseous pollutants resulted in the generation of fine secondary particles, which were identified as the primary source of pollution in the first two episodes. The third pollution episode occurred during a warming period following a cold front. Relative humidity was lower during this episode, and coarse particles were the major pollution contributor. Results of process analysis indicated that emissions sources, horizontal transport and vertical transport were the primary factors affecting pollutant concentrations within the near-surface layer during all three episodes, while aerosol processes, cloud processes, horizontal transport and vertical transport had greater influence at approximately 900 m above ground. Cloud processes had a greater impact during the first two pollution episodes because of the higher relative humidity. In addition, by comparing pollution processes from different cities (Guangzhou and Zhongshan), the study revealed that the first two pollution episodes were the result of local emissions within the PRD region and transport between surrounding cities, while the third episode exhibited prominent regional pollution characteristics and was the result of regional pollutant transport.

The Effect of Fluid and Solid Properties on the Auxetic Behavior of Porous Materials Having Rock-like Microstructures

NASA Astrophysics Data System (ADS)

Wollner, U.; Vanorio, T.; Kiss, A. M.

2017-12-01

Materials with a negative Poisson's Ratio (PR), known as auxetics, exhibit the counterintuitive behavior of becoming wider when uniaxially stretched and thinner when compressed. Though negative PR is characteristic of polymer foams or cellular solids, tight as well as highly porous rocks have also been reported to exhibit a negative Poisson's ratio, both from dynamic (PRd) and static measurements. We propose a novel auxetic structure based on pore-space configuration observed in rocks. First, we performed 2D and 3D imaging of a pumice and tight basalt to analyze their rock microstructure as well as similarities to natural structures of auxetic materials - e.g., cork. Based on these analyses, we developed a theoretical auxetic 3D model consisting of rotating rigid bodies having pore configurations similar to those observed in rocks. To alleviate the mechanical assumption of rotating bodies, the theoretical model was modified to include crack-like features being represented by intersecting, elliptic cylinders. We then used a 3D printer to create a physical version of the modified model, whose PRd was tested. We also numerically explored how the compressibility of fluids located in the pore-space of the modified model as well as how the elastic properties of the material from which the model is made of affect its auxetic behavior. We conclude that for a porous medium composed of a single material saturated with a single fluid (a) the more compliant the fluid is and (b) the lower the PR of the solid material, the lower the PR value of the composite material.

Transfer rates of enteric microorganisms in recycled water during machine clothes washing.

PubMed

O'Toole, Joanne; Sinclair, Martha; Leder, Karin

2009-03-01

Approximately 15% of overall Australian household water usage is in the laundry; hence, a significant reduction in household drinking water demand could be achieved if potable-quality water used for clothes washing is replaced with recycled water. To investigate the microbiological safety of using recycled water in washing machines, bacteriophages MS-2 and PRD-1, Escherichia coli, and Cryptosporidium parvum oocysts were used in a series of experiments to investigate the transfer efficiency of enteric microorganisms from washing machine water to objects including hands, environmental surfaces, air, and fabric swatches. By determining the transference efficiency, it is possible to estimate the numbers of microorganisms that the user will be exposed to if recycled water with various levels of residual microorganisms is used in washing machines. Results, expressed as transfer rates to a given surface area per object, showed that the mean transfer efficiency of E. coli, bacteriophages MS-2 and PRD-1, and C. parvum oocysts from seeded water to fabric swatches ranged from 0.001% to 0.090%. Greatest exposure to microorganisms occurred through direct contact of hands with seeded water and via hand contact with contaminated fabric swatches. No microorganisms were detected in the air samples during the washing machine spin cycle, and transfer rates of bacteriophages from water to environmental surfaces were 100-fold less than from water directly to hands. Findings from this study provide relevant information that can be used to refine regulations governing recycled water and to allay public concerns about the use of recycled water.

Guidance: The practical management of the gastrointestinal symptoms of pelvic radiation disease

PubMed Central

Andreyev, H Jervoise N; Muls, Ann C; Norton, Christine; Ralph, Charlotte; Watson, Lorraine; Shaw, Clare; Lindsay, James O

2015-01-01

Background A recent randomised trial suggested that an algorithmic approach to investigating and managing gastrointestinal symptoms of pelvic radiation disease (PRD) is beneficial and that specially trained nurses can manage patients as effectively as a gastroenterologist. Aims The aim of the development and peer review of the guide was to make the algorithm used in the trial accessible to all levels of clinician. Methods Experts who manage patients with PRD were asked to review the guide, rating each section for agreement with the recommended measures and suggesting amendments if necessary. Specific comments were discussed and incorporated as appropriate, and this process was repeated for a second round of review. Results 34 gastroenterologists, 10 nurses, 9 dietitians, 7 surgeons and 5 clinical oncologists participated in round one. Consensus (defined prospectively as 60% or more panellists selecting ‘strongly agree’ or ‘agree’) was reached for 27 of the original 28 sections in the guide, with a median of 75% of panellists agreeing with each section. 86% of panellists agreed that the guide was acceptable for publication or acceptable with minor revisions. 55 of the original 65 panellists participated in round two. 89% agreed it was acceptable for publication after the first revision. Further minor amendments were made in response to round two. Conclusions Development of the guide in response to feedback included ▸ improvement of occasional algorithmic steps ▸ a more user-friendly layout ▸ clearer timeframes for referral to other teams ▸ expansion of reference list ▸ addition of procedures to the appendix. PMID:25580207

Poliovirus infection induces the co-localization of cellular protein SRp20 with TIA-1, a cytoplasmic stress granule protein

PubMed Central

Fitzgerald, Kerry D.; Semler, Bert L.

2013-01-01

Different types of environmental stress cause mammalian cells to form cytoplasmic foci, termed stress granules, which contain mRNPs that are translationally silenced. These foci are transient and dynamic, and contain components of the cellular translation machinery as well as certain mRNAs and RNA binding proteins. Stress granules are known to be induced by conditions such as hypoxia, nutrient deprivation, and oxidative stress, and a number of cellular factors have been identified that are commonly associated with these foci. More recently it was discovered that poliovirus infection also induces the formation of stress granules, although these cytoplasmic foci appear to be somewhat compositionally unique. Work described here examined the punctate pattern of SRp20 (a host cell mRNA splicing protein) localization in the cytoplasm of poliovirus-infected cells, demonstrating the partial co-localization of SRp20 with the stress granule marker protein TIA-1. We determined that SRp20 does not co-localize with TIA-1, however, under conditions of oxidative stress, indicating that the close association of these two proteins during poliovirus infection is not representative of a general response to cellular stress. We confirmed that the expression of a dominant negative version of TIA-1 (TIA-1-PRD) results in the dissociation of stress granules. Finally, we demonstrated that expression of wild type TIA-1 or dominant negative TIA-1-PRD in cells during poliovirus infection does not dramatically affect viral translation. Taken together, these studies provide a new example of the unique cytoplasmic foci that form during poliovirus infection. PMID:23830997

Is "pelvic radiation disease" always the cause of bowel symptoms following prostate cancer intensity-modulated radiotherapy?

PubMed

Min, Myo; Chua, Benjamin; Guttner, Yvonne; Abraham, Ned; Aherne, Noel J; Hoffmann, Matthew; McKay, Michael J; Shakespeare, Thomas P

2014-02-01

Pelvic radiation disease (PRD) also widely known as "radiation proctopathy" is a well recognised late side-effect following conventional prostate radiotherapy. However, endoscopic evaluation and/or specialist referral for new or persistent post-prostate radiotherapy bowel symptoms is not routine and serious diagnoses may potentially be missed. Here we report a policy of endoscopic evaluation of bowel symptoms persisting >90 days post radiotherapy for prostate cancer. A consecutive series of 102 patients who had radical prostate intensity-modulated radiotherapy (IMRT)/image-guided radiotherapy (IGRT) and who had new or ongoing bowel symptoms or positive faecal occult blood tests (FOBT) on follow up visits more than three months after treatment, were referred for endoscopic examination. All but one (99%) had full colonoscopic investigation. Endoscopic findings included gastric/colonic/rectal polyps (56%), diverticular disease (49%), haemorrhoids (38%), radiation proctopathy (29%), gastritis/oesophagitis (8%) and rarer diagnoses, including bowel cancer which was found in 3%. Only four patients (4%) had radiation proctopathy without associated pathology and 65 patients (63%) had more than one diagnosis. If flexible sigmoidoscopy alone were used, 36.6% of patients and 46.6% patients with polyp(s) would have had their diagnoses missed. Our study has shown that bowel symptoms following prostate IMRT/IGRT are due to numerous diagnoses other than PRD, including malignancy. Routine referral pathways should be developed for endoscopic evaluation/specialist review for patients with new or persistent bowel symptoms (or positive FOBT) following prostate radiotherapy. This recommendation should be considered for incorporation into national guidelines. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Polaron hopping in olivine phosphates studied by nuclear resonant scattering

NASA Astrophysics Data System (ADS)

Tracy, Sally June

Valence fluctuations of Fe2+ and Fe3+ were studied in a solid solution of LixFePO4 by nuclear resonant forward scattering of synchrotron x rays while the sample was heated in a diamond-anvil pressure cell. The spectra acquired at different temperatures and pressures were analyzed for the frequencies of valence changes using the Blume-Tjon model of a system with a fluctuating Hamiltonian. These frequencies were analyzed to obtain activation energies and an activation volume for polaron hopping. There was a large suppression of hopping frequency with pressure, giving an anomalously large activation volume. This large, positive value is typical of ion diffusion, which indicates correlated motions of polarons, and Li+ ions that alter the dynamics of both. In a parallel study of NaxFePO4, the interplay between sodium ordering and electron mobility was investigated using a combination of synchrotron x-ray diffraction and nuclear resonant scattering. Conventional Mossbauer spectra were collected while the sample was heated in a resistive furnace. An analysis of the temperature evolution of the spectral shapes was used to identify the onset of fast electron hopping and determine the polaron hopping rate. Synchrotron x-ray diffraction measurements were carried out in the same temperature range. Reitveld analysis of the diffraction patterns was used to determine the temperature of sodium redistribution on the lattice. The diffraction analysis also provides new information about the phase stability of the system. The temperature evolution of the iron site occupancies from the Mossbauer measurements, combined with the synchrotron diffraction results give strong evidence for a relationship between the onset of fast electron dynamics and the redistribution of sodium in the lattice. Measurements of activation barriers for polaron hopping gave fundamental insights about the correlation between electronic carriers and mobile ions. This work established that polaron-ion interactions can alter the local dynamics of electron and ion transport. These types of coupled processes may be common in many materials used for battery electrodes, and new details concerning the influence of polaron-ion interactions on the charge dynamics are relevant to optimizing their electrochemical performance.

[Task redistribution in Dutch dental care in relation to dental hygienists' job satisfaction].

PubMed

Jerkovic, K; van Offenbeek, M A G; van der Schans, C P

2010-05-01

In research into a professional cross-section of dental hygienists, we studied the extent to which task redistribution has an influence on job satisfaction. The research among randomly chosen dental hygienists consisted of questions about organizational and personal characteristics, the set of assigned tasks, task characteristics and job satisfaction. The respondents were divided into 3 clusters which differed in the breadth of their sets of tasks. Although prevention and periodontology services remain the core tasks in dental hygienists' jobs, the degree of task redistribution differed strongly from cluster to cluster. Respondents with a considerable degree of task redistribution experienced the most task variation, but scored significantly lower on the task characteristics autonomy, feedback, task identity and task importance. This explains why redistribution does not directly correspond with a greater degree of job satisfaction. Moreover, it is precisely the dental hygienists with a broad set of tasks who are significantly less satisfied with their salary than those with a traditional set of tasks.

Unequal views of inequality: Cross-national support for redistribution 1985-2011.

PubMed

VanHeuvelen, Tom

2017-05-01

This research examines public views on government responsibility to reduce income inequality, support for redistribution. While individual-level correlates of support for redistribution are relatively well understood, many questions remain at the country-level. Therefore, I examine how country-level characteristics affect aggregate support for redistribution. I test explanations of aggregate support using a unique dataset combining 18 waves of the International Social Survey Programme and European Social Survey. Results from mixed-effects logistic regression and fixed-effects linear regression models show two primary and contrasting effects. States that reduce inequality through bundles of tax and transfer policies are rewarded with more supportive publics. In contrast, economic development has a seemingly equivalent and dampening effect on public support. Importantly, the effect of economic development grows at higher levels of development, potentially overwhelming the amplifying effect of state redistribution. My results therefore suggest a fundamental challenge to proponents of egalitarian politics. Copyright © 2016 Elsevier Inc. All rights reserved.

Local redistribution of blood under the effect of fixation stress against a background of hypokinesia

NASA Technical Reports Server (NTRS)

Kovalev, O. A.; Lysak, V. F.; Severovostokova, V. I.; Shermetevskaya, S. K.

1980-01-01

Fixation stress was used as a model of emotional disturbance. The effect of previous restrictions on mobility on the local redistribution of blood resulting from fixation stress was examined. Disturbances in carbohydrate which result from prolonged hypokinesia was studied. Radioactivity was used to determine the local redistribution of blood. Modified factor analysis was used to study the results of the experiment.

Verifiable Secret Redistribution

DTIC Science & Technology

2001-10-01

but they are not trusted with secret. Thus, we require a protocol for redistribution without reconstruction of the secret . We also require...verification that the new shareholders have valid shares (ones that can be used to reconstruct the secret ). We present a new protocol to perform non...secret to shareholders in Shamir’s (m,n) threshold scheme (one in which we require m of n shares to reconstruct the secret ), and wish to redistribute the

Overlap in nitrogen sources and redistribution of nitrogen between trees and grasses in a semi-arid savanna.

PubMed

Priyadarshini, K V R; Prins, Herbert H T; de Bie, Steven; Heitkönig, Ignas M A; Woodborne, Stephan; Gort, Gerrit; Kirkman, Kevin; Fry, Brian; de Kroon, Hans

2014-04-01

A key question in savanna ecology is how trees and grasses coexist under N limitation. We used N stable isotopes and N content to study N source partitioning across seasons from trees and associated grasses in a semi-arid savanna. We also used (15)N tracer additions to investigate possible redistribution of N by trees to grasses. Foliar stable N isotope ratio (δ(15)N) values were consistent with trees and grasses using mycorrhiza-supplied N in all seasons except in the wet season when they switched to microbially fixed N. The dependence of trees and grasses on mineralized soil N seemed highly unlikely based on seasonal variation in mineralization rates in the Kruger Park region. Remarkably, foliar δ(15)N values were similar for all three tree species differing in the potential for N fixation through nodulation. The tracer experiment showed that N was redistributed by trees to understory grasses in all seasons. Our results suggest that the redistribution of N from trees to grasses and uptake of N was independent of water redistribution. Although there is overlap of N sources between trees and grasses, dependence on biological sources of N coupled with redistribution of subsoil N by trees may contribute to the coexistence of trees and grasses in semi-arid savannas.

Topographic Controls on Soil Carbon Distribution in Iowa Croplands, USA

NASA Astrophysics Data System (ADS)

McCarty, Greg; Li, Xia

2017-04-01

Topography is a key factor affecting soil organic carbon (SOC) redistribution (erosion or deposition) because it influences several hydrological indices including soil moisture dynamics, runoff velocity and acceleration, and flow divergence and convergence. In this study, we examined the relationship between 15 topographic metrics derived from Light Detection and Ranging (Lidar) data and SOC redistribution in agricultural fields. We adopted the fallout 137Cesium (137Cs) technique to estimate SOC redistribution rates across 560 sampling plots in Iowa. Then, using stepwise ordinarily least square regression (SOLSR) and stepwise principle component analysis (SPCA), topography-based SOC models were developed to simulate spatial patterns of SOC content and redistribution. Results suggested that erosion and deposition of topsoil SOC were regulated by topography with SOC gain in lowland areas and SOC loss in sloping areas. Topographic wetness index (TWI) and slope were the most influential variables controlling SOC content and redistribution. The topography-based models exhibited good performances in simulating SOC content and redistribution across two crop sites with intensive samplings. SPCA models had slightly lower coefficients of determination and Nash-Sutcliffe efficiency values compared to SOLSR models at the field scale. However, significantly SPCA outperformed SOLAR in predicting SOC redistribution patterns at the watershed scale. Results of this study suggest that the topography-based SPCA model was more robust for scaling up models to the watershed scale because SPCA models may better represent the landscapes and are less subject to over fitting. This work suggests an improved method to sample and characterize landscapes for better prediction of soil property distribution.

Mechanisms of Ocean Heat Uptake

NASA Astrophysics Data System (ADS)

Garuba, Oluwayemi

An important parameter for the climate response to increased greenhouse gases or other radiative forcing is the speed at which heat anomalies propagate downward in the ocean. Ocean heat uptake occurs through passive advection/diffusion of surface heat anomalies and through the redistribution of existing temperature gradients due to circulation changes. Atlantic meridional overturning circulation (AMOC) weakens in a warming climate and this should slow the downward heat advection (compared to a case in which the circulation is unchanged). However, weakening AMOC also causes a deep warming through the redistributive effect, thus increasing the downward rate of heat propagation compared to unchanging circulation. Total heat uptake depends on the combined effect of these two mechanisms. Passive tracers in a perturbed CO2 quadrupling experiments are used to investigate the effect of passive advection and redistribution of temperature anomalies. A new passive tracer formulation is used to separate ocean heat uptake into contributions due to redistribution and passive advection-diffusion of surface heating during an ocean model experiment with abrupt increase in surface temperature. The spatial pattern and mechanisms of each component are examined. With further experiments, the effects of surface wind, salinity and temperature changes in changing circulation and the resulting effect on redistribution in the individual basins are isolated. Analysis of the passive advection and propagation path of the tracer show that the Southern ocean dominates heat uptake, largely through vertical and horizontal diffusion. Vertical diffusion transports the tracer across isopycnals down to about 1000m in 100 years in the Southern ocean. Advection is more important in the subtropical cells and in the Atlantic high latitudes, both with a short time scale of about 20 years. The shallow subtropical cells transport the tracer down to about 500m along isopycnal surfaces, below this vertical diffusion takes over transport in the tropics; in the Atlantic, the MOC transports heat as deep 2000m in about 30 years. Redistributive surface heat uptake alters the total amount surface heat uptake among the basins. Compared to the passive-only heat uptake, which is about the same among the basins, redistribution nearly doubles the surface heat input into the Atlantic but makes smaller increases in the Indian and Pacific oceans for a net global increase of about 25%, in the perturbation experiment with winds unchanged. The passive and redistributive heat uptake components are further distributed among the basins through the global conveyor belt. The Pacific gains twice the surface heat input into it through lateral transport from the other two basins, as a result, the Atlantic and Pacific gain similar amounts of heat even though surface heat input is in the Atlantic is much bigger. Of this heat transport, most of the passive component comes from the Indian and the redistributive component comes from the Atlantic. Different surface forcing perturbation gives different circulation change pattern and as a result yield different redistributive uptake. Ocean heat uptake is more sensitive to wind forcing perturbation than to thermohaline forcing perturbation. About 2% reduction in subtropical cells transport and southern ocean transport, in the wind-change perturbation experiment, resulted in about 10% reduction in the global ocean heat uptake of wind-unchanged experiment. The AMOC weakened by about 35% and resulted in a 25% increase in passive heat uptake in the wind-unchanged experiment. Surface winds weakening reduces heat uptake by warming the reservoir surface temperatures, while MOC weakening increases heat input by a cooling reservoir surface temperatures. Thermohaline forcing perturbation is combination of salinity and temperature perturbations, both weaken the AMOC, however, they have opposite redistributive effects. Ocean surface freshening gives positive redistributive effect, while surface temperature increase gives negative redistributive effect on heat uptake. The salinity effect dominates the redistributive effect for thermohaline perturbation.

Pressure Ulcer Risk and Prevention Practices in Pediatric Patients: A Secondary Analysis of Data from the National Database of Nursing Quality Indicators®.

PubMed

Razmus, Ivy; Bergquist-Beringer, Sandra

2017-01-01

Little is known about pressure ulcer prevention practice among pediatric patients. To describe the frequency of pressure ulcer risk assessment in pediatric patients and pressure ulcer prevention intervention use overall and by hospital unit type, a descriptive secondary analysis was performed of data submitted to the National Database for Nursing Quality Indicators® (NDNQI®) for at least 3 of the 4 quarters in 2012. Relevant data on pressure ulcer risk from 271 hospitals across the United States extracted from the NDNQI database included patient skin and pressure ulcer risk assessment on admission, time since the last pressure ulcer risk assessment, method used to assess pressure ulcer risk, and risk status. Extracted data on pressure ulcer prevention included skin assessment, pressure-redistribution surface use, routine repositioning, nutritional support, and moisture management. These data were organized by unit type and merged with data on hospital characteristics for the analysis. The sample included 39 984 patients ages 1 day to 18 years on 678 pediatric acute care units (general pediatrics, pediatric critical care units, neonatal intensive care units, pediatric step-down units, and pediatric rehabilitation units). Descriptive statistics were used to analyze study data. Most of the pediatric patients (33 644; 89.2%) were assessed for pressure ulcer risk within 24 hours of admission. The Braden Q Scale was frequently used to assess risk on general pediatrics units (75.4%), pediatric step-down units (85.5%), pediatric critical care units (81.3%), and pediatric rehabilitation units (56.1%). In the neonatal intensive care units, another scale or method was used more often (55% to 60%) to assess pressure ulcer risk. Of the 11 203 pediatric patients (39%) determined to be at risk for pressure ulcers, the majority (10 741, 95.8%) received some kind of pressure ulcer prevention intervention during the 24 hours preceding the NDNQI pressure ulcer survey. The frequency of prevention intervention use among those at risk ranged from 99.2% for skin assessment to 70.7% for redistribution surface use. Most pediatric patients are being assessed for pressure ulcer risk, but the implementation of interventions to prevent pressure ulcers among children needs to be improved. Future qualitative research should be conducted to determine how and when clinical judgment is used to assess pressure ulcer risk and the type of pressure-redistribution surfaces used among younger pediatric patients.

The complexity and implications of yeast prion domains

PubMed Central

2011-01-01

Prions are infectious proteins with altered conformations converted from otherwise normal host proteins. While there is only one known mammalian prion protein, PrP, a handful of prion proteins have been identified in the yeast Saccharomyces cerevisiae. Yeast prion proteins usually have a defined region called prion domain (PrD) essential for prion properties, which are typically rich in glutamine (Q) and asparagine (N). Despite sharing several common features, individual yeast PrDs are generally intricate and divergent in their compositional characteristics, which potentially implicates their prion phenotypes, such as prion-mediated transcriptional regulations. PMID:22156731

Thin-metal lined PRD 49-III composite vessels. [evaluation of pressure vessels for burst strength and fatigue performance

NASA Technical Reports Server (NTRS)

Hoggatt, J. T.

1974-01-01

Filament wound pressure vessels of various configurations were evaluated for burst strength and fatigue performance. The dimensions and characteristics of the vessels are described. The types of tests conducted are explained. It was determined that all vessels leaked in a relatively few cycles (20 to 60 cycles) with failure occurring in all cases in the metallic liner. The thin liner would de-bond from the composite and buckling took place during depressurization. No composite failures or indications of impeding composite failures were obtained in the metal-lined vessels.

Hydraulic Redistribution: A Modeling Perspective

NASA Astrophysics Data System (ADS)

Daly, E.; Verma, P.; Loheide, S. P., III

2014-12-01

Roots play a key role in the soil water balance. They extract and transport water for transpiration, which usually represents the most important soil water loss in vegetated areas, and can redistribute soil water, thereby increasing transpiration rates and enhancing root nutrient uptake. We present here a two-dimensional model capable of describing two key aspects of root water uptake: root water compensation and hydraulic redistribution. Root water compensation is the ability of root systems to respond to the reduction of water uptake from areas of the soil with low soil water potential by increasing the water uptake from the roots in soil parts with higher water potential. Hydraulic redistribution is a passive transfer of water through the root system from areas of the soil with greater water potential to areas with lower water potential. Both mechanisms are driven by gradients of water potential in the soil and the roots. The inclusion of root water compensation and hydraulic redistribution in models can be achieved by describing root water uptake as a function of the difference in water potential between soil and root xylem. We use a model comprising the Richards equation for the water flow in variably saturated soils and the Darcy's equation for the water flow in the xylem. The two equations are coupled via a sink term, which is assumed to be proportional to the difference between soil and xylem water potentials. The model is applied in two case studies to describe vertical and horizontal hydraulic redistribution and the interaction between vegetation with different root depths. In the case of horizontal redistribution, the model is used to reproduce the fluxes of water across the root system of a tree subjected to uneven irrigation. This example can be extended to situations when only part of the root system has access to water, such as vegetation near creeks, trees at the edge of forests, and street trees in urban areas. The second case is inspired by recent agro-ecosystems experiments that combined different vegetation species to increase crop yield. The presence of deep rooted plants (nursing species) near shallow rooted crops (nursed species) enhanced crop growth thanks to vertical and horizontal hydraulic redistribution. The model is able to reproduce the patterns of water redistribution observed in this scenario.

An efficient and guaranteed stable numerical method for continuous modeling of infiltration and redistribution with a shallow dynamic water table

NASA Astrophysics Data System (ADS)

Lai, Wencong; Ogden, Fred L.; Steinke, Robert C.; Talbot, Cary A.

2015-03-01

We have developed a one-dimensional numerical method to simulate infiltration and redistribution in the presence of a shallow dynamic water table. This method builds upon the Green-Ampt infiltration with Redistribution (GAR) model and incorporates features from the Talbot-Ogden (T-O) infiltration and redistribution method in a discretized moisture content domain. The redistribution scheme is more physically meaningful than the capillary weighted redistribution scheme in the T-O method. Groundwater dynamics are considered in this new method instead of hydrostatic groundwater front. It is also computationally more efficient than the T-O method. Motion of water in the vadose zone due to infiltration, redistribution, and interactions with capillary groundwater are described by ordinary differential equations. Numerical solutions to these equations are computationally less expensive than solutions of the highly nonlinear Richards' (1931) partial differential equation. We present results from numerical tests on 11 soil types using multiple rain pulses with different boundary conditions, with and without a shallow water table and compare against the numerical solution of Richards' equation (RE). Results from the new method are in satisfactory agreement with RE solutions in term of ponding time, deponding time, infiltration rate, and cumulative infiltrated depth. The new method, which we call "GARTO" can be used as an alternative to the RE for 1-D coupled surface and groundwater models in general situations with homogeneous soils with dynamic water table. The GARTO method represents a significant advance in simulating groundwater surface water interactions because it very closely matches the RE solution while being computationally efficient, with guaranteed mass conservation, and no stability limitations that can affect RE solvers in the case of a near-surface water table.

Cognitive ability and the demand for redistribution.

PubMed

Mollerstrom, Johanna; Seim, David

2014-01-01

Empirical research suggests that the cognitively able are politically more influential than the less able, by being more likely to vote and to assume leadership positions. This study asks whether this pattern matters for public policy by investigating what role a person's cognitive ability plays in determining his preferences for redistribution of income among citizens in society. To answer this question, we use a unique Swedish data set that matches responses to a tailor-made questionnaire to administrative tax records and to military enlistment records for men, with the latter containing a measure of cognitive ability. On a scale of 0 to 100 percent redistribution, a one-standard-deviation increase in cognitive ability reduces the willingness to redistribute by 5 percentage points, or by the same amount as a $35,000 increase in mean annual income. We find support for two channels mediating this economically strong and statistically significant relation. First, higher ability is associated with higher income. Second, ability is positively correlated with the view that economic success is the result of effort, rather than luck. Both these factors are, in turn, related to lower demand for redistribution.

Modeling Water Redistribution in a Near-Surface Arid Soil

NASA Astrophysics Data System (ADS)

Luo, Y.; Ghezzehei, T. A.; Berli, M.; Dijkema, J.; Koonce, J.

2017-12-01

Desert soils cover about one third of the Earth's land surface and play an important role in the ecology and hydrology of arid environments. Despite their large extend, relatively little is known about their near-surface (top centimeters to meter) water dynamics. Recent studies by Koonce (2016) and Dijkema et al. (2017) shed light on the water dynamics of near-surface arid soil but also revealed some of the challenges to simulate the water redistribution in arid soils. The goal of this study was to improve water redistribution simulations in near-surface arid soils by employing more advanced hydraulic conductivity functions. Expanding on the work by Dijkema et al. (2017), we used a HYDRUS-1D model with different hydraulic conductivity functions to simulate water redistribution within the soil as a function of precipitation, evaporation and drainage. Model calculations were compared with measured data from the SEPHAS weighing lysimeters in Boulder City, NV. Preliminary results indicate that water redistribution simulations of near-surface arid soils can be improved by using hydraulic conductivity functions that can capture capillary, film and vapor flow, like for example the Peter-Durner-Iden (PDI) model.

Cognitive Ability and the Demand for Redistribution

PubMed Central

Mollerstrom, Johanna; Seim, David

2014-01-01

Empirical research suggests that the cognitively able are politically more influential than the less able, by being more likely to vote and to assume leadership positions. This study asks whether this pattern matters for public policy by investigating what role a person's cognitive ability plays in determining his preferences for redistribution of income among citizens in society. To answer this question, we use a unique Swedish data set that matches responses to a tailor-made questionnaire to administrative tax records and to military enlistment records for men, with the latter containing a measure of cognitive ability. On a scale of 0 to 100 percent redistribution, a one-standard-deviation increase in cognitive ability reduces the willingness to redistribute by 5 percentage points, or by the same amount as a $35,000 increase in mean annual income. We find support for two channels mediating this economically strong and statistically significant relation. First, higher ability is associated with higher income. Second, ability is positively correlated with the view that economic success is the result of effort, rather than luck. Both these factors are, in turn, related to lower demand for redistribution. PMID:25343713

Collisional redistribution of radiation. III - The equation of motion for the correlation function and the scattered spectrum

NASA Technical Reports Server (NTRS)

Burnett, K.; Cooper, J.

1980-01-01

Computations were made of the scattering of monochromatic radiation by a degenerate atom in the binary-collision approximation for field strengths whose products of the Rabi frequency for atomic transition and the duration of a strong collision are much less than 1. An expression of motion for the correlation function is derived which does not exclude the region where thermal correlations may be neglected; the equation is valid outside the quantum-regression regime, and has a straightforward solution for practical cases. Solutions for the weak-field linear response regime are presented in terms of generalized absorption and emission profiles which depend on the indices of the atomic multipoles.

Stereological analysis of gravitropism in protonemata of the moss Ceratodon

NASA Technical Reports Server (NTRS)

Walker, L. M.; Sack, F. D.

1997-01-01

Apical cells of dark-grown protonemata of the moss Cerotodon purpureus are negatively gravitropic. Previous light microscopy has shown that reorientation to the horizontal induces amyloplast sedimentation and redistribution of microtubules. To determine whether other components become redistributed laterally or axially, the apical 35 micrometers of both vertical and horizontal apical cells were compared stereologically using transmission electron microscopy. Reorientation to the horizontal changed the longitudinal distributions of tubular ER, Golgi stacks, and vesicles but not cisternal ER, mitochondria, and plastids. Only plastids showed a statistically significant lateral redistribution after horizontal placement. Qualitative examination of the sedimentation zone showed plastids sedimented close to peripherally located ER with vacuoles displaced above plastids. These results argue against a model where differential tip growth results from a redistribution of Golgi stacks or exocytic vesicles.

The Deserving Poor, the Family, and the U.S. Welfare System

PubMed Central

Moffitt, Robert A.

2015-01-01

Contrary to the popular view that the U.S. welfare system has been in a contractionary phase after the expansions of the welfare state in the 1960s, welfare spending resumed steady growth after a pause in the 1970s. However, while aggregate spending is higher than ever, there has been a redistribution away from non-elderly and non-disabled families to families with older adults and to families with recipients of disability programs, a redistribution away from non-elderly nondisabled single parent families to married parent families, and a redistribution of transfers away from the poorest families to those with higher incomes. These redistributions likely reflect long-standing, and perhaps increasing, conceptualizations by U.S. society of which poor are deserving and which are not. PMID:26047935

On analysis of electroencephalogram by multiresolution-based energetic approach

NASA Astrophysics Data System (ADS)

Sevindir, Hulya Kodal; Yazici, Cuneyt; Siddiqi, A. H.; Aslan, Zafer

2013-10-01

Epilepsy is a common brain disorder where the normal neuronal activity gets affected. Electroencephalography (EEG) is the recording of electrical activity along the scalp produced by the firing of neurons within the brain. The main application of EEG is in the case of epilepsy. On a standard EEG some abnormalities indicate epileptic activity. EEG signals like many biomedical signals are highly non-stationary by their nature. For the investigation of biomedical signals, in particular EEG signals, wavelet analysis have found prominent position in the study for their ability to analyze such signals. Wavelet transform is capable of separating the signal energy among different frequency scales and a good compromise between temporal and frequency resolution is obtained. The present study is an attempt for better understanding of the mechanism causing the epileptic disorder and accurate prediction of occurrence of seizures. In the present paper following Magosso's work [12], we identify typical patterns of energy redistribution before and during the seizure using multiresolution wavelet analysis on Kocaeli University's Medical School's data.

Small gravitationally elicited voltage transients in pea stems

NASA Technical Reports Server (NTRS)

Pickard, B. G.

1984-01-01

Decapitated veritcal stem segments were observed for 45 min, noting the number of transients mu V for each 5-min interval. Results for two sets of stem segments are plotted. The average frequencies were 0.72 + or -0.05 and 0.66 + or - 0.04 per 5 min. One set of segments was swiveled gently to the horizontal position; then, recording continued for another 90 min. Transients continued in the vertical controls at a closely similar average rate 0.78 + or - 0.04 per 5 min. However, after the first 5-min interval the horizontally placed plants exhibited transients at an increased average rate of 1.08 + or - 0.04 per 5 min. The frequency of transients also increased following horizontal placement of intact shoots. However, it appears that this increase had two components: one due to gravity reception, and one due to the redistribution of indolacetic acid (IAA) believed to mediate gravitropic curvature (or, more specifically, to the increase of IAA in the lower tissue.

Emerging investigator series: As( v ) in magnetite: incorporation and redistribution

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huhmann, Brittany L.; Neumann, Anke; Boyanov, Maxim I.

2017-01-01

As coprecipitated with magnetite remained incorporated over time whereas sorbed As was redistributed and became increasingly incorporated into magnetite, both the absence and presence of aqueous Fe(ii).

A comparative analysis of early child health and development services and outcomes in countries with different redistributive policies

PubMed Central

2013-01-01

Background The social environment is a fundamental determinant of early child development and, in turn, early child development is a determinant of health, well-being, and learning skills across the life course. Redistributive policies aimed at reducing social inequalities, such as a welfare state and labour market policies, have shown a positive association with selected health indicators. In this study, we investigated the influence of redistributive policies specifically on the social environment of early child development in five countries with different political traditions. The objective of this analysis was to highlight similarities and differences in social and health services between the countries and their associations with other health outcomes that can inform better global early child development policies and improve early child health and development. Methods Four social determinants of early child development were selected to provide a cross-section of key time periods in a child’s life from prenatal to kindergarten. They included: 1) prenatal care, 2) maternal leave, 3) child health care, and 4) child care and early childhood education. We searched international databases and reports (e.g. Organization for Economic Cooperation and Development, World Bank, and UNICEF) to obtain information about early child development policies, services and outcomes. Results Although a comparative analysis cannot claim causation, our analysis suggests that redistributive policies aimed at reducing social inequalities are associated with a positive influence on the social determinants of early child development. Generous redistributive policies are associated with a higher maternal leave allowance and pay and more preventive child healthcare visits. A decreasing trend in infant mortality, low birth weight rate, and under five mortality rate were observed with an increase in redistributive policies. No clear influence of redistributive policies was observed on breastfeeding and immunization rates. In the analysis of child care and early education, the lack of uniform measures of early child development outcomes was apparent. Conclusions This paper provides further support for an association between redistributive policies and early child health and development outcomes, along with the organization of early child health and development services. PMID:24195544

A comparative analysis of early child health and development services and outcomes in countries with different redistributive policies.

PubMed

van den Heuvel, Meta; Hopkins, Jessica; Biscaro, Anne; Srikanthan, Cinntha; Feller, Andrea; Bremberg, Sven; Verkuijl, Nienke; Flapper, Boudien; Ford-Jones, Elizabeth Lee; Williams, Robin

2013-11-06

The social environment is a fundamental determinant of early child development and, in turn, early child development is a determinant of health, well-being, and learning skills across the life course. Redistributive policies aimed at reducing social inequalities, such as a welfare state and labour market policies, have shown a positive association with selected health indicators. In this study, we investigated the influence of redistributive policies specifically on the social environment of early child development in five countries with different political traditions. The objective of this analysis was to highlight similarities and differences in social and health services between the countries and their associations with other health outcomes that can inform better global early child development policies and improve early child health and development. Four social determinants of early child development were selected to provide a cross-section of key time periods in a child's life from prenatal to kindergarten. They included: 1) prenatal care, 2) maternal leave, 3) child health care, and 4) child care and early childhood education. We searched international databases and reports (e.g. Organization for Economic Cooperation and Development, World Bank, and UNICEF) to obtain information about early child development policies, services and outcomes. Although a comparative analysis cannot claim causation, our analysis suggests that redistributive policies aimed at reducing social inequalities are associated with a positive influence on the social determinants of early child development. Generous redistributive policies are associated with a higher maternal leave allowance and pay and more preventive child healthcare visits. A decreasing trend in infant mortality, low birth weight rate, and under five mortality rate were observed with an increase in redistributive policies. No clear influence of redistributive policies was observed on breastfeeding and immunization rates. In the analysis of child care and early education, the lack of uniform measures of early child development outcomes was apparent. This paper provides further support for an association between redistributive policies and early child health and development outcomes, along with the organization of early child health and development services.

Topographic Metric Predictions of Soil redistribution and Organic Carbon Distribution in Croplands

NASA Astrophysics Data System (ADS)

Mccarty, G.; Li, X.

2017-12-01

Landscape topography is a key factor controlling soil redistribution and soil organic carbon (SOC) distribution in Iowa croplands (USA). In this study, we adopted a combined approach based on carbon () and cesium (137Cs) isotope tracers, and digital terrain analysis to understand patterns of SOC redistribution and carbon sequestration dynamics as influenced by landscape topography in tilled cropland under long term corn/soybean management. The fallout radionuclide 137Cs was used to estimate soil redistribution rates and a Lidar-derived DEM was used to obtain a set of topographic metrics for digital terrain analysis. Soil redistribution rates and patterns of SOC distribution were examined across 560 sampling locations at two field sites as well as at larger scale within the watershed. We used δ13C content in SOC to partition C3 and C4 plant derived C density at 127 locations in one of the two field sites with corn being the primary source of C4 C. Topography-based models were developed to simulate SOC distribution and soil redistribution using stepwise ordinary least square regression (SOLSR) and stepwise principal component regression (SPCR). All topography-based models developed through SPCR and SOLSR demonstrated good simulation performance, explaining more than 62% variability in SOC density and soil redistribution rates across two field sites with intensive samplings. However, the SOLSR models showed lower reliability than the SPCR models in predicting SOC density at the watershed scale. Spatial patterns of C3-derived SOC density were highly related to those of SOC density. Topographic metrics exerted substantial influence on C3-derived SOC density with the SPCR model accounting for 76.5% of the spatial variance. In contrast C4 derived SOC density had poor spatial structure likely reflecting the substantial contribution of corn vegetation to recently sequestered SOC density. Results of this study highlighted the utility of topographic SPCR models for scaling field measurements of SOC density and soil redistribution rates to watershed scale which will allow watershed model to better predict fate of ecosystem C on agricultural landscapes.

The F-Actin Binding Protein Cortactin Regulates the Dynamics of the Exocytotic Fusion Pore through its SH3 Domain

PubMed Central

González-Jamett, Arlek M.; Guerra, María J.; Olivares, María J.; Haro-Acuña, Valentina; Baéz-Matus, Ximena; Vásquez-Navarrete, Jacqueline; Momboisse, Fanny; Martinez-Quiles, Narcisa; Cárdenas, Ana M.

2017-01-01

Upon cell stimulation, the network of cortical actin filaments is rearranged to facilitate the neurosecretory process. This actin rearrangement includes both disruption of the preexisting actin network and de novo actin polymerization. However, the mechanism by which a Ca2+ signal elicits the formation of new actin filaments remains uncertain. Cortactin, an actin-binding protein that promotes actin polymerization in synergy with the nucleation promoting factor N-WASP, could play a key role in this mechanism. We addressed this hypothesis by analyzing de novo actin polymerization and exocytosis in bovine adrenal chromaffin cells expressing different cortactin or N-WASP domains, or cortactin mutants that fail to interact with proline-rich domain (PRD)-containing proteins, including N-WASP, or to be phosphorylated by Ca2+-dependent kinases, such as ERK1/2 and Src. Our results show that the activation of nicotinic receptors in chromaffin cells promotes cortactin translocation to the cell cortex, where it colocalizes with actin filaments. We further found that, in association with PRD-containing proteins, cortactin contributes to the Ca2+-dependent formation of F-actin, and regulates fusion pore dynamics and the number of exocytotic events induced by activation of nicotinic receptors. However, whereas the actions of cortactin on the fusion pore dynamics seems to depend on the availability of monomeric actin and its phosphorylation by ERK1/2 and Src kinases, cortactin regulates the extent of exocytosis by a mechanism independent of actin polymerization. Together our findings point out a role for cortactin as a critical modulator of actin filament formation and exocytosis in neuroendocrine cells. PMID:28522963

Emission factor of ammonia (NH3) from on-road vehicles in China: tunnel tests in urban Guangzhou

NASA Astrophysics Data System (ADS)

Liu, Tengyu; Wang, Xinming; Wang, Boguang; Ding, Xiang; Deng, Wei; Lü, Sujun; Zhang, Yanli

2014-05-01

Ammonia (NH3) is the primary alkaline gas in the atmosphere that contributes to formation of secondary particles. Emission of NH3 from vehicles, particularly gasoline powered light duty vehicles equipped with three-way catalysts, is regarded as an important source apart from emissions from animal wastes and soils, yet measured emission factors for motor vehicles are still not available in China, where traffic-related emission has become an increasingly important source of air pollutants in urban areas. Here we present our tunnel tests for NH3 from motor vehicles under ‘real world conditions’ in an urban roadway tunnel in Guangzhou, a central city in the Pearl River Delta (PRD) region in south China. By attributing all NH3 emissions in the tunnel to light-duty gasoline vehicles, we obtained a fuel-based emission rate of 2.92 ± 0.18 g L-1 and a mileage-based emission factor of 229.5 ± 14.1 mg km-1. These emission factors were much higher than those measured in the United States while measured NO x emission factors (7.17 ± 0.60 g L-1 or 0.56 ± 0.05 g km-1) were contrastingly near or lower than those previously estimated by MOBILE/PART5 or COPERT IV models. Based on the NH3 emission factors from this study, on-road vehicles accounted for 8.1% of NH3 emissions in the PRD region in 2006 instead of 2.5% as estimated in a previous study using emission factors taken from the Emission Inventory Improvement Program (EIIP) in the United States.

Spatial and Interspecies Patterns of PM2.5 at Three Sites in the Pearl River Delta, China: One-Year Observations

NASA Astrophysics Data System (ADS)

Yu, J.; Lau, A. K.; Wu, C.; Ng, W.; Yuan, Z.; Wu, D.

2009-12-01

The Pearl River Delta (PRD) is among the most economically fast-developing regions in China. The region has been experiencing increasing levels of particulate matter (PM) pollution. In an effort of establishing long-term trend in chemical characteristics of PM2.5 and understanding PM sources important at regional scale, filter-based samples have been collected at three sites in the PRD concurrently in one-in-six-day schedule since August 2007. We here report observation results of PM2.5 over one-year period (August 2007-June 2008). The three sites include an urban downtown location in Guangzhou, Nansha, a rural receptor site at the mouth of the Pearl River, and Tsuen Wan, an urban background site in Hong Kong. Guangzhou recorded the highest annual average PM2.5 concentration of 78.2 μgm-3, followed by Nansha (65.9 μgm-3) and Tsuen Wan (42.8 μgm-3). Organic matter (OM) and sulfate are the top two constituents, accounting for ~70% of PM2.5 mass. The annual average nitrate contributions were similar at GZ and NS (~13%), but lower at TW (~7%). Inter-site correlations of PM2.5 and major constituents indicate that GZ strongly influenced ambient PM2.5 levels at NS, but GZ’s influence on TW was much reduced. Sulfate, ammonium, and OM showed strong regional characteristics. To the contrary, EC at the three sites had no correlations, suggesting a dominating local origin. Examples of high PM2.5 episodes are also analyzed to identify the conditions conducive for high PM.

Critical Determinants of Substrate Recognition by Cyclin-Dependent Kinase-like 5 (CDKL5).

PubMed

Katayama, Syouichi; Sueyoshi, Noriyuki; Kameshita, Isamu

2015-05-19

Cyclin-dependent kinase-like 5 (CDKL5) is a Ser/Thr protein kinase known to be associated with X-linked neurodevelopmental disorders. In a previous study, we identified amphiphysin 1 (Amph1) as a potential substrate for CDKL5 and identified a single phosphorylation site at Ser-293. In this study, we investigated the molecular mechanisms of substrate recognition by CDKL5 using Amph1 as a model substrate. Amph1 served as an efficient CDKL5 substrate, whereas Amph2, a structurally related homologue of Amph1, was not phosphorylated by CDKL5. The sequence around the Amph1 phosphorylation site is RPR(293)SPSQ, while the corresponding sequence in Amph2 is IPK(332)SPSQ. To define the amino acid sequence specificity of the substrate, various point mutants of Amph1 and Amph2 were prepared and phosphorylated by CDKL5. Both Amph2(I329R) and Amph1 served as efficient CDKL5 substrates, but Amph1(R290I) did not, indicating that the arginyl residue at the P -3 position is critical for substrate recognition. With regard to prolyl residues around the phosphorylation site of Amph1, Pro-291 at the P -2 position, but not Pro-294 at the P +1 position, is indispensable for phosphorylation by CDKL5. Phosphorylation experiments using various deletion mutants of Amph1 revealed that the proline-rich domain (PRD) (amino acids 247-315) alone was not phosphorylated by CDKL5. In contrast, Amph1(247-385), which comprised the PRD and CLAP domains, served as an efficient CDKL5 substrate. These results, taken together, suggest that both the phosphorylation site sequence (RPXSX) and the CLAP domain structure in Amph1 play crucial roles in recognition and phosphorylation by CDKL5.

Poliovirus infection induces the co-localization of cellular protein SRp20 with TIA-1, a cytoplasmic stress granule protein.

PubMed

Fitzgerald, Kerry D; Semler, Bert L

2013-09-01

Different types of environmental stress cause mammalian cells to form cytoplasmic foci, termed stress granules, which contain mRNPs that are translationally silenced. These foci are transient and dynamic, and contain components of the cellular translation machinery as well as certain mRNAs and RNA binding proteins. Stress granules are known to be induced by conditions such as hypoxia, nutrient deprivation, and oxidative stress, and a number of cellular factors have been identified that are commonly associated with these foci. More recently it was discovered that poliovirus infection also induces the formation of stress granules, although these cytoplasmic foci appear to be somewhat compositionally unique. Work described here examined the punctate pattern of SRp20 (a host cell mRNA splicing protein) localization in the cytoplasm of poliovirus-infected cells, demonstrating the partial co-localization of SRp20 with the stress granule marker protein TIA-1. We determined that SRp20 does not co-localize with TIA-1, however, under conditions of oxidative stress, indicating that the close association of these two proteins during poliovirus infection is not representative of a general response to cellular stress. We confirmed that the expression of a dominant negative version of TIA-1 (TIA-1-PRD) results in the dissociation of stress granules. Finally, we demonstrated that expression of wild type TIA-1 or dominant negative TIA-1-PRD in cells during poliovirus infection does not dramatically affect viral translation. Taken together, these studies provide a new example of the unique cytoplasmic foci that form during poliovirus infection. Copyright © 2013 Elsevier B.V. All rights reserved.

Estimation of health and economic costs of air pollution over the Pearl River Delta region in China.

PubMed

Lu, Xingcheng; Yao, Teng; Fung, Jimmy C H; Lin, Changqing

2016-10-01

The Pearl River Delta region (PRD) is the economic growth engine of China and also one of the most urbanized regions in the world. As a two-sided sword, rapid economic development causes air pollution and poses adverse health effects to the citizens in this area. This work estimated the negative health effects in the PRD caused by the four major ambient pollutants (SO2, NO2, O3 and PM10) from 2010 to 2013 by using a log linear exposure-response function and the WRF-CMAQ modeling system. Economic loss due to mortality and morbidity was evaluated by the value of statistical life (VSL) and cost of illness (COI) methods. The results show that the overall possible short-term all-cause mortality due to NO2, O3 and PM10 reached the highest in 2013 with the values being 13,217-22,800. The highest total economic loss, which ranged from 14,768 to 25,305million USD, occurred in 2013 and was equivalent to 1.4%-2.3% of the local gross domestic product. The monthly profile of cases of negative health effects varied by city and the types of ambient pollutants. The ratio of mortality attributed to air pollutants to total population was higher in urban areas than in rural areas. People living in the countryside should consider the possible adverse health effects of urban areas before they plan a move to the city. The results show that the health burden caused by the ambient pollutants over this region is serious and suggest that tighter control policies should be implemented in the future to reduce the level of air pollution. Copyright © 2016 Elsevier B.V. All rights reserved.

Simulation of ozone formation at different elevations in mountainous area of Hong Kong using WRF-CMAQ model.

PubMed

Wang, N; Guo, H; Jiang, F; Ling, Z H; Wang, T

2015-02-01

Field measurements were simultaneously conducted at a mountain (Mt.) site (Tai Mao Shan, TMS) and an urban site (Tsuen Wan, TW) at the foot of the Mt. TMS in Hong Kong. An interesting event with consecutive high-ozone (O₃) days from 08:00 on 28 Oct. to 23:00 on 03 Nov., 2010 was observed at Mt. TMS, while no such polluted event was found at the foot of the mountain. The Weather Research and Forecasting (WRF)-Community Multiscale Air Quality (CMAQ) models were used to understand this event. Model performance evaluation showed that the simulated meteorological parameters and air pollutants were well in agreement with the observations. The index of agreement (IOA) of temperature, relative humidity, wind direction and wind speed were 0.93, 0.83, 0.46 and 0.60, respectively. The multi-day high O₃ episode at Mt. TMS was also reasonably reproduced (IOA=0.68). Horizontally, the photochemical processes determined the O₃ levels in southwestern Pearl River Delta (PRD) and the Pearl River Estuary (PRE), while in eastern and northern PRD, the O₃ destruction was over the production during the event. Vertically, higher O₃ values at higher levels were found at both Mt. TMS and TW, indicating a vertical O₃ gradient over Hong Kong. With the aid of the process analysis module, we found positive contribution of vertical transport including advection and diffusion to O₃ mixing ratios at the two sites, suggesting that O₃ values at lower locations could be affected by O₃ at higher locations via vertical advection and diffusion over Hong Kong. Copyright © 2014 Elsevier B.V. All rights reserved.

Binding to the minor groove of the double-strand, tau protein prevents DNA from damage by peroxidation.

PubMed

Wei, Yan; Qu, Mei-Hua; Wang, Xing-Sheng; Chen, Lan; Wang, Dong-Liang; Liu, Ying; Hua, Qian; He, Rong-Qiao

2008-07-02

Tau, an important microtubule associated protein, has been found to bind to DNA, and to be localized in the nuclei of both neurons and some non-neuronal cells. Here, using electrophoretic mobility shifting assay (EMSA) in the presence of DNA with different chain-lengths, we observed that tau protein favored binding to a 13 bp or a longer polynucleotide. The results from atomic force microscopy also showed that tau protein preferred a 13 bp polynucleotide to a 12 bp or shorter polynucleotide. In a competitive assay, a minor groove binder distamycin A was able to replace the bound tau from the DNA double helix, indicating that tau protein binds to the minor groove. Tau protein was able to protect the double-strand from digestion in the presence of DNase I that was bound to the minor groove. On the other hand, a major groove binder methyl green as a negative competitor exhibited little effect on the retardation of tau-DNA complex in EMSA. This further indicates the DNA minor groove as the binding site for tau protein. EMSA with truncated tau proteins showed that both the proline-rich domain (PRD) and the microtubule-binding domain (MTBD) contributed to the interaction with DNA; that is to say, both PRD and MTBD bound to the minor groove of DNA and bent the double-strand, as observed by electron microscopy. To investigate whether tau protein is able to prevent DNA from the impairment by hydroxyl free radical, the chemiluminescence emitted by the phen-Cu/H(2)O(2)/ascorbate was measured. The emission intensity of the luminescence was markedly decreased when tau protein was present, suggesting a significant protection of DNA from the damage in the presence of hydroxyl free radical.

Numerical study on seasonal variations of gaseous pollutants and particulate matters in Hong Kong/Pearl River Delta Region

NASA Astrophysics Data System (ADS)

Kwok, Roger Hiu Fung

Air pollution in Hong Kong (HK) causes problems in visibility and public health, which are worsening over past few years. Out of particulate matters (PM) inhalable into respiratory system, 30% is contributed by sulfate (SO4), 40% by organic carbon (OC), and 10% by elemental carbon (EC). A meso-scale numerical modeling system CMAQ is devised to simulate the air quality in January (winter), April (spring), July (summer) and October (autumn) 2004, driven by meteorology simulated by MM5 and emission sources in China including Hong Kong. Observational and measurement data from Hong Kong Environmental Protection Department Air Quality network are compared with the model results. With respect to pollutant concentration level, model-observation agreement is reasonably well, especially in PM species sulfate, organic carbon (OC) and elemental carbon (EC); and gaseous species SO2, NOx and ozone. In terms of PM composition, the model agrees with the measurement in fractions of sulfate, OC and EC. Higher PM level in autumn and winter is associated with northeasterly winds due to continental outflow. To further investigate emission sources contributing to HK, a source apportioning method called Tagged Species Source Apportionment (TSSA) algorithm is applied to study contributions to level of SO4, SO2 and EC in HK. It is found that while sources beyond PRD are observed in entire HK during January and October 2004, emitting sectors are different among western HK, downtown area, and the east countryside. Specifically, power plants and vehicles from HK and Shenzhen affect the western new towns, while power plants, vehicles and ships within HK determine the downtown pollutants' level. The countryside is mainly influenced by sources beyond PRD.

A method for apportionment of natural and anthropogenic contributions to heavy metal loadings in the surface soils across large-scale regions.

PubMed

Hu, Yuanan; Cheng, Hefa

2016-07-01

Quantification of the contributions from anthropogenic sources to soil heavy metal loadings on regional scales is challenging because of the heterogeneity of soil parent materials and high variability of anthropogenic inputs, especially for the species that are primarily of lithogenic origin. To this end, we developed a novel method for apportioning the contributions of natural and anthropogenic sources by combining sequential extraction and stochastic modeling, and applied it to investigate the heavy metal pollution in the surface soils of the Pearl River Delta (PRD) in southern China. On the average, 45-86% of Zn, Cu, Pb, and Cd were present in the acid soluble, reducible, and oxidizable fractions of the surface soils, while only 12-24% of Ni, Cr, and As were partitioned in these fractions. The anthropogenic contributions to the heavy metals in the non-residual fractions, even the ones dominated by natural sources, could be identified and quantified by conditional inference trees. Combination of sequential extraction, Kriging interpolation, and stochastic modeling reveals that approximately 10, 39, 6.2, 28, 7.1, 15, and 46% of the As, Cd, Cr, Cu, Ni, Pb, and Zn, respectively, in the surface soils of the PRD were contributed by anthropogenic sources. These results were in general agreements with those obtained through subtraction of regional soil metal background from total loadings, and the soil metal inputs through atmospheric deposition as well. In the non-residual fractions of the surface soils, the anthropogenic contributions to As, Cd, Cr, Cu, Ni, Pb, and Zn, were 48, 42, 50, 51, 49, 24, and 70%, respectively. Copyright © 2016 Elsevier Ltd. All rights reserved.

Phytoavailability and phytovariety codetermine the bioaccumulation risk of heavy metal from soils, focusing on Cd-contaminated vegetable farms around the Pearl River Delta, China.

PubMed

Hu, Junli; Wu, Fuyong; Wu, Shengchun; Sun, Xiaolin; Lin, Xiangui; Wong, Ming Hung

2013-05-01

Five random vegetable farms were selected to investigate the bioaccumulation risk of heavy metals (HMs) by different type of vegetables around the Pearl River Delta (PRD), China. The concentration order of four major HMs in the surface soil samples was Cd

Akt recruits Dab2 to albumin endocytosis in the proximal tubule.

PubMed

Koral, Kelly; Li, Hui; Ganesh, Nandita; Birnbaum, Morris J; Hallows, Kenneth R; Erkan, Elif

2014-12-15

Proximal tubule epithelial cells have a highly sophisticated endocytic machinery to retrieve the albumin in the glomerular filtrate. The megalin-cubilin complex and the endocytic adaptor disabled-2 (Dab2) play a pivotal role in albumin endocytosis. We previously demonstrated that protein kinase B (Akt) regulates albumin endocytosis in the proximal tubule through an interaction with Dab2. Here, we examined the nature of Akt-Dab2 interaction. The pleckstrin homology (PH) and catalytic domains (CD) of Akt interacted with the proline-rich domain (PRD) of Dab2 based on yeast-two hybrid (Y2H) experiments. Pull-down experiments utilizing the truncated constructs of Dab2 demonstrated that the initial 11 amino acids of Dab2-PRD were sufficient to mediate the interaction between Akt and Dab2. Endocytosis experiments utilizing Akt1- and Akt2-silencing RNA revealed that both Akt1 and Akt2 mediate albumin endocytosis in proximal tubule epithelial cells; therefore, Akt1 and Akt2 may play a compensatory role in albumin endocytosis. Furthermore, both Akt isoforms phosphorylated Dab2 at Ser residues 448 and 449. Ser-to-Ala mutations of these Dab2 residues inhibited albumin endocytosis and resulted in a shift in location of Dab2 from the peripheral to the perinuclear area, suggesting the physiological relevance of these phosphorylation sites in albumin endocytosis. We conclude that both Akt1 and Akt2 are involved in albumin endocytosis, and phosphorylation of Dab2 by Akt induces albumin endocytosis in proximal tubule epithelial cells. Further delineation of how Akt affects expression/phosphorylation of endocytic adaptors and receptors will enhance our understanding of the molecular network triggered by albumin overload in the proximal tubule. Copyright © 2014 the American Physiological Society.

Characterization of anthropogenic impacts in a large urban center by examining the spatial distribution of halogenated flame retardants.

PubMed

Wei, Yan-Li; Bao, Lian-Jun; Wu, Chen-Chou; Zeng, Eddy Y

2016-08-01

Anthropogenic impacts have continuously intensified in mega urban centers with increasing urbanization and growing population. The spatial distribution pattern of such impacts can be assessed with soil halogenated flame retardants (HFRs) as HFRs are mostly derived from the production and use of various consumer products. In the present study, soil samples were collected from the Pearl River Delta (PRD), a large urbanized region in southern China, and its surrounding areas and analyzed for a group of HFRs, i.e., polybrominated diphenyl ethers (PBDEs), decabromodiphenyl ethane, bis(hexachlorocyclopentadieno)cyclooctane (DP) and hexabromobenzene. The sum concentrations of HFRs and PBDEs were in the ranges of 0.66-6500 and 0.37-5700 (mean: 290 and 250) ng g(-1) dry weight, respectively, around the middle level of the global range. BDE-209 was the predominant compound likely due to the huge amounts of usage and its persistence. The concentrations of HFRs were greater in the land-use types of residency, industry and landfill than in agriculture, forestry and drinking water source, and were also greater in the central PRD than in its surrounding areas. The concentrations of HFRs were moderately significantly (r(2) = 0.32-0.57; p < 0.05) correlated with urbanization levels, population densities and gross domestic productions in fifteen administrative districts. The spatial distribution of DP isomers appeared to be stereoselective as indicated by the similarity in the spatial patterns for the ratio of anti-DP versus the sum of DP isomers (fanti-DP) and DP concentrations. Finally, the concentrations of HFRs sharply decreased with increasing distance from an e-waste recycling site, indicating that e-waste derived HFRs largely remained in local soil. Copyright © 2016 Elsevier Ltd. All rights reserved.

Hourly peak concentration measuring the PM2.5-mortality association: Results from six cities in the Pearl River Delta study

NASA Astrophysics Data System (ADS)

Lin, Hualiang; Ratnapradipa, Kendra; Wang, Xiaojie; Zhang, Yonghui; Xu, Yanjun; Yao, Zhenjiang; Dong, Guanghui; Liu, Tao; Clark, Jessica; Dick, Rebecca; Xiao, Jianpeng; Zeng, Weilin; Li, Xing; Qian, Zhengmin (Min); Ma, Wenjun

2017-07-01

Compared with daily mean concentration of air pollution, hourly peak concentration may be more directly relevant to the acute health effects due to the high concentration levels, however, few have analyzed the acute mortality effects of hourly peak levels of air pollution. We examined the associations of hourly peak concentration of fine particulate matter air pollution (PM2.5) with mortality in six cities in Pearl River Delta, China. We used generalized additive Poisson models to examine the associations with adjustment for potential confounders in each city. We further applied random-effects meta-analyses to estimate the regional overall effects. We further estimated the mortality burden attributable to hourly peak and daily mean PM2.5. We observed significant associations between hourly peak PM2.5 and mortality. Each 10 μg/m3 increase in 4-day averaged (lag03) hourly peak PM2.5 corresponded to a 0.9% [95% confidence interval (CI): 0.7%, 1.1%] increase in total mortality, 1.2% (95% CI: 1.0%, 1.5%) in cardiovascular mortality, and 0.7% (95% CI: 0.2%, 1.1%) in respiratory mortality. We observed a greater mortality burden using hourly peak PM2.5 than daily mean PM2.5, with an estimated 12915 (95% CI: 9922, 15949) premature deaths attributable to hourly peak PM2.5, and 7951 (95% CI: 5067, 10890) to daily mean PM2.5 in the Pearl River Delta (PRD) region during the study period. This study suggests that hourly peak PM2.5 might be one important risk factor of mortality in PRD region of China; the finding provides important information for future air pollution management and epidemiological studies.

An Ultra-Low Power Turning Angle Based Biomedical Signal Compression Engine with Adaptive Threshold Tuning

PubMed Central

Zhou, Jun; Wang, Chao

2017-01-01

Intelligent sensing is drastically changing our everyday life including healthcare by biomedical signal monitoring, collection, and analytics. However, long-term healthcare monitoring generates tremendous data volume and demands significant wireless transmission power, which imposes a big challenge for wearable healthcare sensors usually powered by batteries. Efficient compression engine design to reduce wireless transmission data rate with ultra-low power consumption is essential for wearable miniaturized healthcare sensor systems. This paper presents an ultra-low power biomedical signal compression engine for healthcare data sensing and analytics in the era of big data and sensor intelligence. It extracts the feature points of the biomedical signal by window-based turning angle detection. The proposed approach has low complexity and thus low power consumption while achieving a large compression ratio (CR) and good quality of reconstructed signal. Near-threshold design technique is adopted to further reduce the power consumption on the circuit level. Besides, the angle threshold for compression can be adaptively tuned according to the error between the original signal and reconstructed signal to address the variation of signal characteristics from person to person or from channel to channel to meet the required signal quality with optimal CR. For demonstration, the proposed biomedical compression engine has been used and evaluated for ECG compression. It achieves an average (CR) of 71.08% and percentage root-mean-square difference (PRD) of 5.87% while consuming only 39 nW. Compared to several state-of-the-art ECG compression engines, the proposed design has significantly lower power consumption while achieving similar CRD and PRD, making it suitable for long-term wearable miniaturized sensor systems to sense and collect healthcare data for remote data analytics. PMID:28783079

An Ultra-Low Power Turning Angle Based Biomedical Signal Compression Engine with Adaptive Threshold Tuning.

PubMed

Zhou, Jun; Wang, Chao

2017-08-06

Intelligent sensing is drastically changing our everyday life including healthcare by biomedical signal monitoring, collection, and analytics. However, long-term healthcare monitoring generates tremendous data volume and demands significant wireless transmission power, which imposes a big challenge for wearable healthcare sensors usually powered by batteries. Efficient compression engine design to reduce wireless transmission data rate with ultra-low power consumption is essential for wearable miniaturized healthcare sensor systems. This paper presents an ultra-low power biomedical signal compression engine for healthcare data sensing and analytics in the era of big data and sensor intelligence. It extracts the feature points of the biomedical signal by window-based turning angle detection. The proposed approach has low complexity and thus low power consumption while achieving a large compression ratio (CR) and good quality of reconstructed signal. Near-threshold design technique is adopted to further reduce the power consumption on the circuit level. Besides, the angle threshold for compression can be adaptively tuned according to the error between the original signal and reconstructed signal to address the variation of signal characteristics from person to person or from channel to channel to meet the required signal quality with optimal CR. For demonstration, the proposed biomedical compression engine has been used and evaluated for ECG compression. It achieves an average (CR) of 71.08% and percentage root-mean-square difference (PRD) of 5.87% while consuming only 39 nW. Compared to several state-of-the-art ECG compression engines, the proposed design has significantly lower power consumption while achieving similar CRD and PRD, making it suitable for long-term wearable miniaturized sensor systems to sense and collect healthcare data for remote data analytics.

2016 winter campaigns on ClNO2 and N2O5 at a mountain top and a semi-rural site in southern China: overview and initial results

NASA Astrophysics Data System (ADS)

Wang, T.; Wang, W.; Yun, H.; Tham, Y. J.; Xia, M.; Yu, C.; Wang, Z.; Zhang, N.; Cui, L.; Poon, S.; Lee, S.; Ou, Y.; Yue, D.; Zhai, Y.

2017-12-01

In the past decade, heterogeneous uptake of dinitrogen pentoxide (N2O5) on aerosol and subsequent production of nitryl chloride (ClNO2) have been found to impact the oxidative capacity, NOx fate, and the formation of aerosol nitrate and photochemical ozone. However, the detailed processes and effects are not completely understand for diverse environments of the globe. Our previous measurements at a mountain top (957 m a.s.l) in Hong Kong in winter 2013 revealed elevated concentrations of N2O5 (up to 7.7 ppb) and ClNO2 (up to 4.7 ppb) and that the polluted air masses originated from inland urban areas of the Pearl River delta (PRD). To understand the detailed uptake processes, an intensive measurement campaign was conducted at the same site (Tai Mo Shan, TMS) during October-December 2016 and at a semi-rural site (Heshan) in the center of the PRD in January 2017. Key parameters related to N2O5 and ClNO2 processes, including aerosol ionic composition, aerosol number and size, volatile organic compounds as well as ozone, NOx and NOy, were measured during the two campaigns. Elevated (up to 3.4 ppb) ClNO2 concentrations were observed at the mountain site on many nights a few hours after sunset, and extremely high levels of ClNO2 (up to 8.3 ppb) were measured in the inland site during a heavy pollution event. The meteorological conditions and variations of ClNO2 will be examined with concurrently measured parameters to elucidate factors determining N2O5 uptake and ClNO2 production. The 2016 results at TMS will be compared with those from 2013.

Aromatic hydrocarbons as ozone precursors before and after outbreak of the 2008 financial crisis in the Pearl River Delta region, south China

NASA Astrophysics Data System (ADS)

Zhang, Yanli; Wang, Xinming; Blake, Donald R.; Li, Longfeng; Zhang, Zhou; Wang, Shaoyi; Guo, Hai; Lee, Frank S. C.; Gao, Bo; Chan, Loyin; Wu, Dui; Rowland, F. Sherwood

2012-08-01

In the second half of 2008 China's highly industrialized Pearl River Delta (PRD) region was hard-hit by the financial crisis (FC). This study reports volatile organic compounds measured in the PRD during November-December in both 2007 before the FC and 2008 after the FC. While total mixing ratios of non-methane hydrocarbons (NMHCs) on average were only about 7% lower from 40.2 ppbv in 2007 to 37.5 ppbv in 2008, their ozone formation potentials (OFPs) dropped about 30%, resulting from about 55% plummet of aromatic hydrocarbons (AHs) against a greater than 20% increase of total alkanes/alkenes. The elevated alkanes and alkenes in 2008 could be explained by greater emissions from vehicle exhausts and LPG combustion due to rapid increase of vehicle numbers and LPG consumption; the drop of AHs could be explained by reduced emissions from industries using AH-containing solvents due to the influence of the FC, as indicated by much lower ratios of toluene to benzene and of xylenes/trichloroethylene/tetrachloroethylene to carbon monoxide (CO) in 2008. Source apportionment by positive matrix factorization (PMF) also revealed much less contribution of industry solvents to total anthropogenic NMHCs and particularly to toluene and xylenes in 2008 than in 2007. Based on PMF reconstructed source contributions, calculated OFPs by industrial emissions were responsible for 40.8% in 2007 in contrast to 18.4% in 2008. Further investigation into local industry output statistics suggested that the plummet of AHs in 2008 should be attributed to small enterprises, which contributed largely to ambient AHs due to their huge numbers and non-existent emission treatment, but were much more influenced by the FC.

Ambient air benzene at background sites in China's most developed coastal regions: exposure levels, source implications and health risks.

PubMed

Zhang, Zhou; Wang, Xinming; Zhang, Yanli; Lü, Sujun; Huang, Zhonghui; Huang, Xinyu; Wang, Yuesi

2015-04-01

Benzene is a known human carcinogen causing leukemia, yet ambient air quality objectives for benzene are not available in China. The ambient benzene levels at four background sites in China's most developed coastal regions were measured from March 2012 to February 2013. The sites are: SYNECP, in the Northeast China Plain (NECP); YCNCP, in the North China Plain (NCP); THYRD, in the Yangtze River Delta (YRD) and DHPRD, in the Pearl River Delta (PRD). It was found that the mean annual benzene levels (578-1297 ppt) at the background sites were alarmingly higher, especially when compared to those of 60-480 pptv monitored in 28 cities in the United States. Wintertime benzene levels were significantly elevated at both sites (SYNECP and YCNCP) in northern China due to heating with coal/biofuels. Even at these background sites, the lifetime cancer risks of benzene (1.7-3.7E-05) all exceeded 1E-06 set by USEPA as acceptable for adults. At both sites in northern China, good correlations between benzene and CO or chloromethane, together with much lower toluene/benzene (T/B) ratios, suggested that benzene was largely related to coal combustion and biomass/biofuel burning. At the DHPRD site in the PRD, benzene revealed a highly significant correlation with methyl tert-butyl ether (MTBE), indicating that its source was predominantly from vehicle emissions. At the THYRD site in the YRD, higher T/B ratios and correlations between benzene and tetrachloroethylene, or MTBE, implied that benzene levels were probably affected by both traffic-related and industrial emissions. Copyright © 2015 Elsevier B.V. All rights reserved.

DNA commission of the International Society of Forensic Genetics: Recommendations on the evaluation of STR typing results that may include drop-out and/or drop-in using probabilistic methods

PubMed Central

Gill, P.; Gusmão, L.; Haned, H.; Mayr, W.R.; Morling, N.; Parson, W.; Prieto, L.; Prinz, M.; Schneider, H.; Schneider, P.M.; Weir, B.S.

2015-01-01

DNA profiling of biological material from scenes of crimes is often complicated because the amount of DNA is limited and the quality of the DNA may be compromised. Furthermore, the sensitivity of STR typing kits has been continuously improved to detect low level DNA traces. This may lead to (1) partial DNA profiles and (2) detection of additional alleles. There are two key phenomena to consider: allelic or locus ‘drop-out’, i.e. ‘missing’ alleles at one or more genetic loci, while ‘drop-in’ may explain alleles in the DNA profile that are additional to the assumed main contributor(s). The drop-in phenomenon is restricted to 1 or 2 alleles per profile. If multiple alleles are observed at more than two loci then these are considered as alleles from an extra contributor and analysis can proceed as a mixture of two or more contributors. Here, we give recommendations on how to estimate probabilities considering drop-out, Pr(D), and drop-in, Pr(C). For reasons of clarity, we have deliberately restricted the current recommendations considering drop-out and/or drop-in at only one locus. Furthermore, we offer recommendations on how to use Pr(D) and Pr(C) with the likelihood ratio principles that are generally recommended by the International Society of Forensic Genetics (ISFG) as measure of the weight of the evidence in forensic genetics. Examples of calculations are included. An Excel spreadsheet is provided so that scientists and laboratories may explore the models and input their own data. PMID:22864188

PM2.5, Population Exposure and Economic Effects in Urban Agglomerations of China Using Ground-Based Monitoring Data

PubMed Central

Shen, Yonglin

2017-01-01

This paper adopts the PM2.5 concentration data obtained from 1497 station-based monitoring sites, population and gross domestic product (GDP) census data, revealing population exposure and economic effects of PM2.5 in four typical urban agglomerations of China, i.e., Beijing-Tianjin-Hebei (BTH), the Yangtze River delta (YRD), the Pearl River delta (PRD), and Chengdu-Chongqing (CC). The Cokriging interpolation method was used to estimate the PM2.5 concentration from station-level to grid-level. Next, an evaluation was conducted mainly at the grid-level with a cell size of 1 × 1 km, assisted by the urban agglomeration scale. Criteria including the population-weighted mean, the cumulative percent distribution and the correlation coefficient were applied in our evaluation. The results showed that the spatial pattern of population exposure in BTH was consistent with that of PM2.5 concentration, as well as changes in elevation. The topography was also an important factor in the accumulation of PM2.5 in CC. Moreover, the most polluted urban agglomeration based on the population-weighted mean was BTH, while the least was PRD. In terms of the cumulative percent distribution, only 0.51% of the population who lived in the four urban agglomerations, and 2.33% of the GDP that was produced in the four urban agglomerations, were associated with an annual PM2.5 concentration smaller than the Chinese National Ambient Air Quality Standard of 35 µg/m3. This indicates that the majority of people live in the high air polluted areas, and economic development contributes to air pollution. Our results are supported by the high correlation between population exposure and the corresponding GDP in each urban agglomeration. PMID:28671643

Climatology of cloud-base height from long-term radiosonde measurements in China

NASA Astrophysics Data System (ADS)

Zhang, Yong; Zhang, Lejian; Guo, Jianping; Feng, Jinming; Cao, Lijuan; Wang, Yang; Zhou, Qing; Li, Liangxu; Li, Bai; Xu, Hui; Liu, Lin; An, Ning; Liu, Huan

2018-02-01

Clouds are critical to the global radiation budget and hydrological cycle, but knowledge is still poor concerning the observed climatology of cloud-base height (CBH) in China. Based on fine-resolution sounding observations from the China Radiosonde Network (CRN), the method used to estimate CBH was modified, and uncertainty analyses indicated that the CBH is good enough. The accuracy of CBH estimation is verified by the comparison between the sounding-derived CBHs and those estimated from the micro-pulse lidar and millimeter-wave cloud radar. As such, the CBH climatology was compiled for the period 2006-16. Overall, the CBH exhibits large geographic variability across China, at both 0800 Local Standard Time (LST) and 2000 LST, irrespective of season. In addition, the summertime cloud base tends to be elevated to higher altitudes in dry regions [i.e., Inner Mongolia and the North China Plain (NCP)]. By comparison, the Tibetan Plateau (TP), Pearl River Delta (PRD) and Sichuan Basin (SCB) have relatively low CBHs (< 2.4 km above ground level). In terms of seasonality, the CBH reaches its maximum in summer and minimum in winter. A low cloud base tends to occur frequently (> 70%) over the TP, PRD and SCB. In contrast, at most sites over the Yangtze River Delta (YRD) and the NCP, about half the cloud belongs to the high-cloud category. The CBH does not exhibit marked diurnal variation in summer, throughout all CRN sites, probably due to the persistent cloud coverage caused by the East Asia Summer Monsson. To the best of our knowledge, this is the first CBH climatology produced from sounding measurements in China, and provides a useful reference for obtaining observational cloud base information.

Arsenic contamination in the freshwater fish ponds of Pearl River Delta: bioaccumulation and health risk assessment.

PubMed

Cheng, Zhang; Chen, Kun-Ci; Li, Kai-Bin; Nie, Xiang-Ping; Wu, Sheng Chun; Wong, Chris Kong-Chu; Wong, Ming-Hung

2013-07-01

This study investigated the extent of arsenic (As) contamination in five common species of freshwater fish (northern snakehead [Channa argus], mandrarin fish [Siniperca chuatsi], largemouth bass [Lepomis macrochirous], bighead carp [Aristichthys nobilis] and grass carp [Ctenopharyngodon idellus]) and their associated fish pond sediments collected from 18 freshwater fish ponds around the Pearl River Delta (PRD). The total As concentrations detected in fish muscle and sediment in freshwater ponds around the PRD were 0.05-3.01 mg kg(-1) wet weight (w. wt) and 8.41-22.76 mg kg(-1) dry weight (d. wt), respectively. In addition, the As content was positively correlated (p < 0.05) to total organic carbon (TOC) contents in sediments. Biota sediment accumulation factor (BSAF) showed that omnivorous fish and zooplankton accumulated higher concentrations of heavy metals from the sediment than carnivorous fish. In addition, feeding habits of fish also influence As accumulation in different fish species. In this study, two typical food chains of the aquaculture ponds were selected for investigation: (1) omnivorous food chain (zooplankton, grass carp and bighead carp) and (2) predatory food chain (zooplankton, mud carp and mandarin fish). Significant linear relationships were obtained between log As and δ (15)N. The slope of the regression (-0.066 and -0.078) of the log transformed As concentrations and δ (15)N values, as biomagnifications power, indicated there was no magnification or diminution of As from lower trophic levels (zooplankton) to fish in the aquaculture ponds. Consumption of largemouth bass, northern snakehead and bighead carp might impose health risks of Hong Kong residents consuming these fish to the local population, due to the fact that its cancer risk (CR) value exceeded the upper limit of the acceptable risk levels (10(-4)) stipulated by the USEPA.

Influence of post pattern and resin cement curing mode on the retention of glass fibre posts.

PubMed

Poskus, L T; Sgura, R; Paragó, F E M; Silva, E M; Guimarães, J G A

2010-04-01

To evaluate the influence of post design and roughness and cement system (dual- or self-cured) on the retention of glass fibre posts. Two tapered and smooth posts (Exacto Cônico No. 2 and White Post No. 1) and two parallel-sided and serrated posts (Fibrekor 1.25 mm and Reforpost No. 2) were adhesively luted with two different resin cements--a dual-cured (Rely-X ARC) and a self-cured (Cement Post)--in 40 single-rooted teeth. The teeth were divided into eight experimental groups (n = 5): PFD--Parallel-serrated-Fibrekor/dual-cured; PRD--Parallel-serrated-Reforpost/dual-cured; TED--Tapered-smooth-Exacto Cônico/dual-cured; TWD--Tapered-smooth-White Post/dual-cured; PFS--Parallel-serrated-Fibrekor/self-cured; PRS--Parallel-serrated-Reforpost/self-cured; TES--Tapered-smooth-Exacto Cônico/self-cured; TWS--Tapered-smooth-White Post/self-cured. The specimens were submitted to a pull-out test at a crosshead speed of 0.5 mm min(-1). Data were analysed using analysis of variance and Bonferroni's multiple comparison test (alpha = 0.05). Pull-out results (MPa) were: PFD = 8.13 (+/-1.71); PRD = 8.30 (+/-0.46); TED = 8.68 (+/-1.71); TWD = 9.35 (+/-1.99); PFS = 8.54 (+/-2.23); PRS = 7.09 (+/-1.96); TES = 8.27 (+/-3.92); TWS = 7.57 (+/-2.35). No statistical significant difference was detected for posts and cement factors and their interaction. The retention of glass fibre posts was not affected by post design or surface roughness nor by resin cement-curing mode. These results imply that the choice for serrated posts and self-cured cements is not related to an improvement in retention.

Rapid movement of wastewater from on-site disposal systems into surface waters in the lower Florida Keys

USGS Publications Warehouse

Paul, John H.; McLaughlin, Molly R.; Griffin, Dale W.; Lipp, Erin K.; Stokes, Rodger; Rose, Joan B.

2000-01-01

Viral tracer studies have been used previously to study the potential for wastewater contamination of surface marine waters in the Upper and Middle Florida Keys. Two bacteriophages, the marine bacteriophage φHSIC and the Salmonella phage PRD1, were used as tracers in injection well and septic tank studies in Saddlebunch Keys of the Lower Florida Keys and in septic tank studies in Boot Key Harbor, Marathon, of the Middle Keys. In Boot Key Harbor, both phages were detected in a canal adjacent to the seeded septic tank within 3 h 15 min of the end of the seed period. The tracer was then detected at all sampling sites in Boot Key Harbor, including one on the opposite side of U. S. Highway 1 in Florida Bay, and at an Atlantic Ocean beach outside Boot Key Harbor. Rates of migration based on first appearance of the phage ranged from 1.7 to 57.5 m h-1. In Saddlebunch Keys, φHSIC and PRD1 were used to seed a residential septic tank and a commercial injection well. The septic tank tracer was not found in any surface water samples. The injection well tracer was first detected at a site most distant from the seed site, a channel that connected Sugarloaf Sound with the Atlantic Ocean. The rate of tracer migration from the injection well to this channel ranged from 66.8 to 141 m h-1. Both tracer studies showed a rapid movement of wastewater from on-site sewage treatment and disposal systems in a southeasterly direction toward the reef tract and Atlantic Ocean, with preferential movement through tidal channels. These studies indicate that wastewater disposal systems currently in widespread use in the Florida Keys can rapidly contaminate the marine environment.

In utero and postnatal exposure to a phytoestrogen-enriched diet increases parameters of acute inflammation in a rat model of TNBS-induced colitis.

PubMed

Seibel, Jan; Molzberger, Almut F; Hertrampf, Torsten; Laudenbach-Leschowski, Ute; Degen, Gisela H; Diel, Patrick

2008-12-01

Inflammatory bowel disease (IBD) is very common in Europe and USA. Its incidence in East Asia has been traditionally low, albeit the risk of IBD increases in Asian immigrants adopting western lifestyles, suggesting a strong role of environmental/dietary factors in IBD. A lifelong exposure to phytoestrogen-rich diets has been associated with a decreased risk of developing breast cancer and might also be protective against IBD. We studied the influence of in utero and postnatal exposure to a phytoestrogen (PE)-rich diet on acute inflammation in an animal model of TNBS-induced colitis. Wistar rats were exposed in utero and postnatally to high (genistein: 240 microg/g feed; daidzein: 232 microg/g feed) or very low levels (genistein and daidzein <10 microg/g feed) of phytoestrogen isoflavones fed to pregnant dams with the diet and throughout nursing. After weaning, the offspring had free access to these diets. At the age of 11 weeks, colitis was induced with an enema of TNBS. After 3 days, animals were sacrificed and tissues were collected for histological evaluation and analysis of molecular markers of inflammation. Animals kept on a PE-rich diet (PRD) had higher colon weights than animals on low PE-levels (PDD), suggesting enhanced acute inflammation by phytoestrogens. This result was supported by histological findings and by analysis of myeloperoxidase activity. Interestingly, relative mRNA and protein expression of cyclooxygenase-2 (COX-2) were modulated in rats on PRD, providing evidence that COX-2, the inducible isoform of the enzyme, is involved in the management of colonic inflammation. Our results suggest that early-in-life exposure to PE might not protect against the development of IBD but enhances the extent of acute inflammation.

Aerosol optical properties and radiative impacts in the Pearl River Delta region of China during the dry season

NASA Astrophysics Data System (ADS)

Mai, Boru; Deng, Xuejiao; Li, Zhanqing; Liu, Jianjun; Xia, Xiang'ao; Che, Huizheng; Liu, Xia; Li, Fei; Zou, Yu; Cribb, Maureen

2018-02-01

Aerosol optical properties and direct radiative effects on surface irradiance were examined using seven years (2006-2012) of Cimel sunphotometer data collected at Panyu—the main atmospheric composition monitoring station in the Pearl River Delta (PRD) region of China. During the dry season (October to February), mean values of the aerosol optical depth (AOD) at 550 nm, the Ångström exponent, and the single scattering albedo at 440 nm (SSA) were 0.54, 1.33 and 0.87, respectively. About 90% of aerosols were dominated by fine-mode strongly absorbing particles. The size distribution was bimodal, with fine-mode particles dominating. The fine mode showed a peak at a radius of 0.12 μm in February and October (˜ 0.10 μm3μm-2). The mean diurnal shortwave direct radiative forcing at the surface, inside the atmosphere ( F ATM), and at the top of the atmosphere, was -33.4±7.0, 26.1±5.6 and -7.3±2.7Wm-2, respectively. The corresponding mean values of aerosol direct shortwave radiative forcing per AOD were -60.0 ± 7.8, 47.3 ± 8.3 and -12.8 ± 3.1 W m-2, respectively. Moreover, during the study period, F ATM showed a significant decreasing trend ( p < 0.01) and SSA increased from 0.87 in 2006 to 0.91 in 2012, suggesting a decreasing trend of absorbing particles being released into the atmosphere. Optical properties and radiative impacts of the absorbing particles can be used to improve the accuracy of inversion algorithms for satellite-based aerosol retrievals in the PRD region and to better constrain the climate effect of aerosols in climate models.

Configuration Effects on Liner Performance

NASA Technical Reports Server (NTRS)

Gerhold, Carl H.; Brown, Martha C.; Jones, Michael G.; Howerton, Brian M.

2012-01-01

The acoustic performance of a duct liner depends not only on the intrinsic properties of the liner but also on the configuration of the duct in which it is used. A series of experiments is performed in the NASA Langley Research Center Curved Duct Test Rig (at Mach 0.275) to evaluate the effect of duct configuration on the acoustic performance of single degree of freedom perforate-over-honeycomb liners. The liners form the sidewalls of the duct's test section. Variations of duct configuration include: asymmetric (liner on one side and hard wall opposite) and symmetric (liner on both sides) wall treatment; inlet and exhaust orientation, in which the sound propagates either against or with the flow; and straight and curved flow path. The effect that duct configuration has on the overall acoustic performance, particularly the shift in frequency and magnitude of peak attenuation, is quantified. The redistribution of incident mode content is shown. The liners constitute the side walls of the liner test section and the scatter of incident horizontal order 1 mode by the asymmetric treatment and order 2 mode by the symmetric treatment into order 0 mode is shown. Scatter of order 0 incident modes into higher order modes is also shown. This redistribution of mode content is significant because it indicates that the liner design can be manipulated such that energy is scattered into more highly attenuated modes, thus enhancing liner performance.

Exposure to inequality affects support for redistribution.

PubMed

Sands, Melissa L

2017-01-24

The distribution of wealth in the United States and countries around the world is highly skewed. How does visible economic inequality affect well-off individuals' support for redistribution? Using a placebo-controlled field experiment, I randomize the presence of poverty-stricken people in public spaces frequented by the affluent. Passersby were asked to sign a petition calling for greater redistribution through a "millionaire's tax." Results from 2,591 solicitations show that in a real-world-setting exposure to inequality decreases affluent individuals' willingness to redistribute. The finding that exposure to inequality begets inequality has fundamental implications for policymakers and informs our understanding of the effects of poverty, inequality, and economic segregation. Confederate race and socioeconomic status, both of which were randomized, are shown to interact such that treatment effects vary according to the race, as well as gender, of the subject.

Master equation theory applied to the redistribution of polarized radiation in the weak radiation field limit. V. The two-term atom

NASA Astrophysics Data System (ADS)

Bommier, Véronique

2017-11-01

Context. In previous papers of this series, we presented a formalism able to account for both statistical equilibrium of a multilevel atom and coherent and incoherent scatterings (partial redistribution). Aims: This paper provides theoretical expressions of the redistribution function for the two-term atom. This redistribution function includes both coherent (RII) and incoherent (RIII) scattering contributions with their branching ratios. Methods: The expressions were derived by applying the formalism outlined above. The statistical equilibrium equation for the atomic density matrix is first formally solved in the case of the two-term atom with unpolarized and infinitely sharp lower levels. Then the redistribution function is derived by substituting this solution for the expression of the emissivity. Results: Expressions are provided for both magnetic and non-magnetic cases. Atomic fine structure is taken into account. Expressions are also separately provided under zero and non-zero hyperfine structure. Conclusions: Redistribution functions are widely used in radiative transfer codes. In our formulation, collisional transitions between Zeeman sublevels within an atomic level (depolarizing collisions effect) are taken into account when possible (I.e., in the non-magnetic case). However, the need for a formal solution of the statistical equilibrium as a preliminary step prevents us from taking into account collisional transfers between the levels of the upper term. Accounting for these collisional transfers could be done via a numerical solution of the statistical equilibrium equation system.

Myocardial viability assessment after acute myocardial infarction: low-dose dobutamine echocardiography versus rest-redistribution thallium-201 SPECT.

PubMed

Castini, D; Bestetti, A; Garbin, M; Di Leo, C; Bigi, R; Sponzilli, C; Concardi, G; Gioventù, M; Tarolo, G L; Lombardi, F; Fiorentini, C

1999-09-01

The presence of tissue viability is of great importance in the prognostic work-up of patients recovering from acute myocardial infarction. However, uncertainty still exists concerning the optimal tool for its assessment. The present study was undertaken in order to compare low-dose dobutamine echocardiography and rest-redistribution thallium SPECT for predicting late improvement of regional left ventricular function after acute myocardial infarction. Fifteen patients undergoing coronary angiography, low-dose dobutamine echocardiography and rest-redistribution thallium SPECT after thrombolyzed anterior acute myocardial infarction were studied. A 3 month follow-up echocardiogram was performed in all patients and 9 underwent coronary revascularization. A significant (> or = 70%) residual stenosis of the infarct-related artery was present in 14 patients, whilst a total occlusion was observed in 1. At 3 month follow-up, 41% of the dyssynergic segments improved. The sensitivity, specificity and accuracy for late wall motion improvement was 61, 89 and 77% for low-dose dobutamine echocardiography and, respectively, 76, 45 and 58% for rest-redistribution thallium SPECT. Tissue viability was detected in 65 and 31% of dyssynergic segments by rest-redistribution thallium SPECT and low-dose dobutamine echocardiography, respectively (p < 0.001). The agreement between the two techniques was 48%. Low-dose dobutamine echocardiography is more accurate than rest-redistribution thallium SPECT for predicting 3 month wall motion improvement in patients with acute anterior myocardial infarction, mainly due to its significantly better specificity.

Usefulness of automatic QT dispersion measurement for detecting exercise-induced myocardial ischemia.

PubMed

Takase, Bonpei; Masaki, Nobuyuki; Hattori, Hidemi; Ishihara, Masayuki; Kurita, Akira

2009-06-01

The electrocardiographic index of QT dispersion (QTd) is related to the occurrence of arrhythmia. In patients with suspected or known coronary artery disease, QTd may be affected by exercise. We investigated whether QTd that is automatically calculated by a newly developed computer system could be used as a marker of exercise-induced myocardial ischemia. The design of this study was prospective and observational. Eighty-three consecutive patients were enrolled in this study. Their QTd was measured at rest and after 3 min of exercise during exercise-stress Thallium-201 scintigraphy and compared with conventional ST-segment changes. The patients were classified into 4 groups (normal group, redistribution group, fixed defect group, redistribution with fixed defect group) based on the result of single photon emission computed tomography. As statistical analysis, one-way ANOVA with post-hoc Scheffe's method, receiver-operating characteristics (ROC) and multiple logistic regression analysis were performed. At rest, QTd was significantly greater (p<0.05) in the fixed defect group (52+/-21 ms) and the redistribution with fixed defect group (53+/-20 ms) than in the normal group (32+/-14 ms) and the redistribution group (31+/-16 ms). However, QTd tended to increase after exercise in the redistribution group, while QTd tended to decrease in the normal group, the fixed defect group, and the redistribution with fixed defect group (QTd after exercise, normal group, 28+/-17 ms, redistribution group, 35+/-19 ms, fixed defect group, 43+/-25 ms, redistribution with fixed defect group, 49+/-27 ms). Exercise significantly increased QTcd (RR interval-corrected QT dispersion) in the redistribution group. The best cut-off values of QTd and QTcd obtained from ROC curves for exercise-induced myocardial ischemia were 41.6 ms and 40.4 ms, respectively (Qtd--AUC 0.68, 95%CI 0.53- 0.83 and QTcd--AUC 0.67, 95%CI 0.55-0.80). Using these values as cut-off ones, QTd, QTcd, and conventional ST-segment change had comparable sensitivities and specificities for detecting exercise-induced myocardial ischemia (sensitivity - 60%, 58% and 49%, respectively;specificity - 78%, 80% and 83%, respectively). In addition, multiple logistic regression analysis showed that QTd (OR=2.01, 95%CI 1.15-4.10, p<0.05), QTcd (OR=2.12, 95% CI 1.02-4.30, p<0.05) and ST-segment change (OR=1.89, 95%CI 1.03-3.40, p<0.05), were the significantly associated with exercise-induced myocardial ischemia. QT dispersion and/or QTcd after exercise could be a useful marker for exercise-induced myocardial ischemia in routine clinical practice.

Constituent Redistribution in U-Zr Metallic Fuel Using the Advanced Fuel Performance Code BISON

DOE Office of Scientific and Technical Information (OSTI.GOV)

Galloway, Jack D.; Unal, Cetin; Matthews, Christopher

2016-09-30

Previous work done by Galloway, et. al. on EBR-II ternary (U-Pu-Zr) fuel constituent redistribution yielded accurate simulation data for the limited data sets of Zr redistribution. The data sets included EPMA scans of two different irradiated rods. First, T179, which was irradiated to 1.9 at% burnup, was analyzed. Second, DP16, which was irradiated to 11 at% burnup, was analyzed. One set of parameters that most accurately represented the zirconium profiles for both experiments was determined. Since the binary fuel (U-Zr) has previously been used as the driver fuel for sodium fast reactors (SFR) as well as being the likely drivermore » fuel if a new SFR is constructed, this same process has been initiated on the binary fuel form. From limited binary EPMA scans as well as other fuel characterization techniques, it has been observed that zirconium redistribution also occurs in the binary fuel, albeit at a reduced rate compared to observation in the ternary fuel, as noted by Kim et. al. While the rate of redistribution has been observed to be slower, numerous metallographs of U-Zr fuel show distinct zone formations.« less

Scale interaction and arrangement in a turbulent boundary layer perturbed by a wall-mounted cylindrical element

NASA Astrophysics Data System (ADS)

Tang, Zhanqi; Jiang, Nan

2018-05-01

This study reports the modifications of scale interaction and arrangement in a turbulent boundary layer perturbed by a wall-mounted circular cylinder. Hot-wire measurements were executed at multiple streamwise and wall-normal wise locations downstream of the cylindrical element. The streamwise fluctuating signals were decomposed into large-, small-, and dissipative-scale signatures by corresponding cutoff filters. The scale interaction under the cylindrical perturbation was elaborated by comparing the small- and dissipative-scale amplitude/frequency modulation effects downstream of the cylinder element with the results observed in the unperturbed case. It was obtained that the large-scale fluctuations perform a stronger amplitude modulation on both the small and dissipative scales in the near-wall region. At the wall-normal positions of the cylinder height, the small-scale amplitude modulation coefficients are redistributed by the cylinder wake. The similar observation was noted in small-scale frequency modulation; however, the dissipative-scale frequency modulation seems to be independent of the cylindrical perturbation. The phase-relationship observation indicated that the cylindrical perturbation shortens the time shifts between both the small- and dissipative-scale variations (amplitude and frequency) and large-scale fluctuations. Then, the integral time scale dependence of the phase-relationship between the small/dissipative scales and large scales was also discussed. Furthermore, the discrepancy of small- and dissipative-scale time shifts relative to the large-scale motions was examined, which indicates that the small-scale amplitude/frequency leads the dissipative scales.

Periodic Variations in the O - C Diagrams of Five Pulsation Frequencies of the DB White Dwarf EC 20058-5234

NASA Astrophysics Data System (ADS)

Dalessio, J.; Sullivan, D. J.; Provencal, J. L.; Shipman, H. L.; Sullivan, T.; Kilkenny, D.; Fraga, L.; Sefako, R.

2013-03-01

Variations in the pulsation arrival time of five independent pulsation frequencies of the DB white dwarf EC 20058-5234 individually imitate the effects of reflex motion induced by a planet or companion but are inconsistent when considered in unison. The pulsation frequencies vary periodically in a 12.9 year cycle and undergo secular changes that are inconsistent with simple neutrino plus photon-cooling models. The magnitude of the periodic and secular variations increases with the period of the pulsations, possibly hinting that the corresponding physical mechanism is located near the surface of the star. The phase of the periodic variations appears coupled to the sign of the secular variations. The standards for pulsation-timing-based detection of planetary companions around pulsating white dwarfs, and possibly other variables such as subdwarf B stars, should be re-evaluated. The physical mechanism responsible for this surprising result may involve a redistribution of angular momentum or a magnetic cycle. Additionally, variations in a supposed combination frequency are shown to match the sum of the variations of the parent frequencies to remarkable precision, an expected but unprecedented confirmation of theoretical predictions. Based on observations obtained at the Southern Astrophysical Research (SOAR) telescope, which is a joint project of the Ministério da Ciência, Tecnologia, e Inovação (MCTI) da República Federativa do Brasil, the US National Optical Astronomy Observatory (NOAO), the University of North Carolina at Chapel Hill (UNC), and Michigan State University (MSU).

Accurate MR thermometry by hyperpolarized 129 Xe.

PubMed

Zhang, Le; Burant, Alex; McCallister, Andrew; Zhao, Victor; Koshlap, Karl M; Degan, Simone; Antonacci, Michael; Branca, Rosa Tamara

2017-09-01

To investigate the temperature dependence of the resonance frequency of lipid-dissolved xenon (LDX) and to assess the accuracy of LDX-based MR thermometry. The chemical shift temperature dependence of water protons, methylene protons, and LDX was measured from samples containing tissues with varying fat contents using a high-resolution NMR spectrometer. LDX results were then used to acquire relative and absolute temperature maps in vivo and the results were compared with PRF-based MR thermometry. The temperature dependence of proton resonance frequency (PRF) is strongly affected by the specific distribution of water and fat. A redistribution of water and fat compartments can reduce the apparent temperature dependence of the water chemical shift from -0.01 ppm/°C to -0.006 ppm, whereas the LDX chemical shift shows a consistent temperature dependence of -0.21 ppm/°C. The use of the methylene protons resonance frequency as internal reference improves the accuracy of LDX-based MR thermometry, but degrades that of PRF-based MR thermometry, as microscopic susceptibility gradients affected lipid and water spins differently. The LDX resonance frequency, with its higher temperature dependence, provides more accurate and precise temperature measurements, both in vitro and in vivo. More importantly, the resonance frequency of nearby methylene protons can be used to extract absolute temperature information. Magn Reson Med 78:1070-1079, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

A density distribution algorithm for bone incorporating local orthotropy, modal analysis and theories of cellular solids.

PubMed

Impelluso, Thomas J

2003-06-01

An algorithm for bone remodeling is presented which allows for both a redistribution of density and a continuous change of principal material directions for the orthotropic material properties of bone. It employs a modal analysis to add density for growth and a local effective strain based analysis to redistribute density. General re-distribution functions are presented. The model utilizes theories of cellular solids to relate density and strength. The code predicts the same general density distributions and local orthotropy as observed in reality.

Food flows in the United Kingdom: The potential of surplus food redistribution to reduce waste.

PubMed

Facchini, Elisa; Iacovidou, Eleni; Gronow, Jan; Voulvoulis, Nikolaos

2017-12-07

The increasing amount of food waste generated as a direct consequence of its excessive production, mismanagement, and wasteful behaviors represents a real challenge in promoting resource efficiency. In the United Kingdom (UK), the lack of robust mass flow data hinders the ability both to understand and address food waste challenges and to devise long-term sustainable prevention strategies. In recognition of these challenges, this paper seeks to (i) provide insights into the UK's annual estimates of food mass flows, including imports, exports, distribution, consumption, surplus food production, and final disposal; and (ii) scrutinize the uptake and redistribution of surplus food as a potential food waste prevention strategy. Evidence collected from several enterprises and community-led initiatives in the UK, and London specifically, supports that there is an increasing potential of making a shift towards food redistribution and reuse. Further analysis has shown that the outreach of food redistribution initiatives in the UK is currently limited, possibly because redistribution efforts remain largely fragmented and independent from each other. It is concluded that a national commitment could be instrumental in encouraging the roll-out of this practice, and governmental support through fiscal incentives could lead to the development of a larger and coherent surplus food redistribution system, ultimately enabling food waste prevention and recovery of food's multidimensional value. This paper deals with the topical issue of the increasing amount of food waste generated as a direct consequence of excessive production, mismanagement, and wasteful behavior, representing a real challenge in achieving sustainability and resource efficiency. Currently, only a small fraction of food is redistributed back into the system. Yet, a considerable fraction of food waste generated is edible; thus, better planning, storage, and coordination amongst the different stakeholders in the food supply chain is required in order to prevent its wastage and promote its reuse in accordance with the waste hierarchy.

Decomposition of ECG by linear filtering.

PubMed

Murthy, I S; Niranjan, U C

1992-01-01

A simple method is developed for the delineation of a given electrocardiogram (ECG) signal into its component waves. The properties of discrete cosine transform (DCT) are exploited for the purpose. The transformed signal is convolved with appropriate filters and the component waves are obtained by computing the inverse transform (IDCT) of the filtered signals. The filters are derived from the time signal itself. Analysis of continuous strips of ECG signals with various arrhythmias showed that the performance of the method is satisfactory both qualitatively and quantitatively. The small amplitude P wave usually had a high percentage rms difference (PRD) compared to the other large component waves.

Statistical performance evaluation of ECG transmission using wireless networks.

PubMed

Shakhatreh, Walid; Gharaibeh, Khaled; Al-Zaben, Awad

2013-07-01

This paper presents simulation of the transmission of biomedical signals (using ECG signal as an example) over wireless networks. Investigation of the effect of channel impairments including SNR, pathloss exponent, path delay and network impairments such as packet loss probability; on the diagnosability of the received ECG signal are presented. The ECG signal is transmitted through a wireless network system composed of two communication protocols; an 802.15.4- ZigBee protocol and an 802.11b protocol. The performance of the transmission is evaluated using higher order statistics parameters such as kurtosis and Negative Entropy in addition to the common techniques such as the PRD, RMS and Cross Correlation.

Modulation of the formation and release of bovine SRS-A in vitro by several anti-anaphylactic drugs.

PubMed

Burka, J F; Eyre, P

1975-01-01

Slow-reacting substance of anaphylaxis (SRS-A) is released immunologically from bovine lung in vitro. Various drugs known to protect calves and other animals during anaphylaxis were tested to investigate their modulation of the formation and release of SRS-A. The anti-inflammatory drugs, meclofenamate and aspirin, potentiated SRS-A release. Chlorphenesin and diethylcarbamazine citrate at high concentrations both inhibited SRS-A release. Two new anti-anaphylactic drugs, PR-D-92-EA and M&B 22,948, were particularly effective in inhibiting SRS-A release at low concentrations. The possible modes of actions of these drugs are discussed.

Subsurface application enhances benefits of manure redistribution

USDA-ARS?s Scientific Manuscript database

Sustainable nutrient management requires redistribution of livestock manure from nutrient-excess areas to nutrient-deficit areas. Field experiments were conducted to assess agronomic and environmental effects of different poultry litter application methods (surface vs. subsurface) and timings (fall ...

76 FR 56482 - Sunshine Act Meeting of the Operations & Regulations Committee of the LSC Board of Directors

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-13

... and Congress statutory changes concerning replacement of decennial census poverty data in the... poverty data, phasing in the first redistribution over two years, and redistributing funds triennially...

Residential relocation and regional redistribution of the elderly in the USA and Germany.

PubMed

Serow, W J; Friedrich, K; Haas, W H

1996-01-01

"This paper reviews some of the principal differences and similarities in the migration and spatial redistribution behavior of the older populations of the USA and of Germany.... The paper is divided into three distinct parts. The paper first reviews actual and prospective redistribution of the older population, with regard to interregional shifts of population as well as to changes in concentration along an urban-rural continuum. Following these macroscopic elements, the paper then moves to a presentation of the results of two ex post facto surveys (one taken in the USA and the other in Germany) of recent older movers in order to compare the motivations expressed for the move and the present degree of satisfaction with it. The concluding section considers the implications of redistribution at both geographic levels and of mover satisfaction in light of political developments as they are presently unfolding in Europe." excerpt

Novel Regulation of Aquaporins during Osmotic Stress1

PubMed Central

Vera-Estrella, Rosario; Barkla, Bronwyn J.; Bohnert, Hans J.; Pantoja, Omar

2004-01-01

Aquaporin protein regulation and redistribution in response to osmotic stress was investigated. Ice plant (Mesembryanthemum crystallinum) McTIP1;2 (McMIPF) mediated water flux when expressed in Xenopus leavis oocytes. Mannitol-induced water imbalance resulted in increased protein amounts in tonoplast fractions and a shift in protein distribution to other membrane fractions, suggesting aquaporin relocalization. Indirect immunofluorescence labeling also supports a change in membrane distribution for McTIP1;2 and the appearance of a unique compartment where McTIP1;2 is expressed. Mannitol-induced redistribution of McTIP1;2 was arrested by pretreatment with brefeldin A, wortmannin, and cytochalasin D, inhibitors of vesicle trafficking-related processes. Evidence suggests a role for glycosylation and involvement of a cAMP-dependent signaling pathway in McTIP1;2 redistribution. McTIP1;2 redistribution to endosomal compartments may be part of a homeostatic process to restore and maintain cellular osmolarity under osmotic-stress conditions. PMID:15299122

Redistributing wealth to families: the advantages of the MYRIADE model.

PubMed

Legendre, François; Lorgnet, Jean-Paul; Thibault, Florence

2005-10-01

This study aims to shed light on the main characteristics of the French system for redistributing wealth to families through tax revenues and social transfers. For the purposes of this exercise, the authors used the MYRIADE microsimulation model, which covers most of the redistribution system, though it is limited to monetary flows such as family benefits, housing allowances, minimum social welfare payments, income tax, and tax on furnished accommodation. The authors used a particular methodology to highlight the way this redistribution works; rather than calculate the difference between each family's disposable income and their gross primary income, they opted to isolate the variation in disposable income that could be attributed to the youngest member of each family where there is at least one child under the age of 25. The average increase in disposable income that this child contributes to his or her family amounts to in200 per month.

Novel regulation of aquaporins during osmotic stress.

PubMed

Vera-Estrella, Rosario; Barkla, Bronwyn J; Bohnert, Hans J; Pantoja, Omar

2004-08-01

Aquaporin protein regulation and redistribution in response to osmotic stress was investigated. Ice plant (Mesembryanthemum crystallinum) McTIP1;2 (McMIPF) mediated water flux when expressed in Xenopus leavis oocytes. Mannitol-induced water imbalance resulted in increased protein amounts in tonoplast fractions and a shift in protein distribution to other membrane fractions, suggesting aquaporin relocalization. Indirect immunofluorescence labeling also supports a change in membrane distribution for McTIP1;2 and the appearance of a unique compartment where McTIP1;2 is expressed. Mannitol-induced redistribution of McTIP1;2 was arrested by pretreatment with brefeldin A, wortmannin, and cytochalasin D, inhibitors of vesicle trafficking-related processes. Evidence suggests a role for glycosylation and involvement of a cAMP-dependent signaling pathway in McTIP1;2 redistribution. McTIP1;2 redistribution to endosomal compartments may be part of a homeostatic process to restore and maintain cellular osmolarity under osmotic-stress conditions.

The redistributional impact of Canada's Employment Insurance Program, 1992–2002.

PubMed

Finnie, Ross; Irvine, Ian

2011-01-01

For a decade or so starting in the early 1990s, Canada’s major income support programs underwent substantial reform. Meanwhile, the economy first lingered in a deep recession and then recovered with a period of strong growth. This paper focuses on how the distributional impact of Employment Insurance (EI) evolved during this period. We find that EI was strongly redistributive throughout the whole period with respect to the earnings of individuals, and somewhat less so for family income. But we also show that the distribution of benefits and contributions changed substantially over time, becoming less redistributive. Somewhat counter-intuitively, both the benefit and contribution sides of the program are shown to be redistributive, even though the contribution structure is regressive. These findings are relevant in the current context, as the economy struggles with a combination of high unemployment and fiscal pressures on government spending.

Medicare financing and redistribution in british columbia, 1992 and 2002.

PubMed

McGrail, Kimberlyn

2007-05-01

Equity in healthcare in British Columbia is defined as the provision of services based on need rather than ability to pay and a separation of contributions to financing from the use of services. Physician and hospital services in Canada are financed mainly through general tax revenues, and there is a perception that this financing is progressive. This paper uses Gini coefficients, concentration indexes and Kakwani indexes of progressivity to assess the progressivity of medicare financing in British Columbia in 1992 and 2002. It also measures the overall redistributive effect of medicare services, considering both contributions to financing and use of hospital and physician services. The conclusion is that medicare does redistribute across income groups, but this redistribution is the result solely of the positive correlation between health status and income; financing is nearly proportionate across income groups, but use is higher among lower-income groups. Informed public debate requires a better understanding of these concepts of equity.

Exposure to inequality affects support for redistribution

PubMed Central

Sands, Melissa L.

2017-01-01

The distribution of wealth in the United States and countries around the world is highly skewed. How does visible economic inequality affect well-off individuals’ support for redistribution? Using a placebo-controlled field experiment, I randomize the presence of poverty-stricken people in public spaces frequented by the affluent. Passersby were asked to sign a petition calling for greater redistribution through a “millionaire’s tax.” Results from 2,591 solicitations show that in a real-world-setting exposure to inequality decreases affluent individuals’ willingness to redistribute. The finding that exposure to inequality begets inequality has fundamental implications for policymakers and informs our understanding of the effects of poverty, inequality, and economic segregation. Confederate race and socioeconomic status, both of which were randomized, are shown to interact such that treatment effects vary according to the race, as well as gender, of the subject. PMID:28069960

Pressure-strain energy redistribution in compressible turbulence: return-to-isotropy versus kinetic-potential energy equipartition

NASA Astrophysics Data System (ADS)

Lee, Kurnchul; Venugopal, Vishnu; Girimaji, Sharath S.

2016-08-01

Return-to-isotropy and kinetic-potential energy equipartition are two fundamental pressure-moderated energy redistributive processes in anisotropic compressible turbulence. Pressure-strain correlation tensor redistributes energy among various Reynolds stress components and pressure-dilatation is responsible for energy reallocation between dilatational kinetic and potential energies. The competition and interplay between these pressure-based processes are investigated in this study. Direct numerical simulations (DNS) of low turbulent Mach number dilatational turbulence are performed employing the hybrid thermal Lattice Boltzman method (HTLBM). It is found that a tendency towards equipartition precedes proclivity for isotropization. An evolution towards equipartition has a collateral but critical effect on return-to-isotropy. The preferential transfer of energy from strong (rather than weak) Reynolds stress components to potential energy accelerates the isotropization of dilatational fluctuations. Understanding of these pressure-based redistributive processes is critical for developing insight into the character of compressible turbulence.

The impact of soil redistribution on SOC pools in a Mediterranean agroforestry catchment

NASA Astrophysics Data System (ADS)

Quijano, Laura; Gaspar, Leticia; Lizaga, Iván; Navas, Ana

2017-04-01

Soil redistribution processes play an important role influencing the spatial distribution patterns of soil and associated soil organic carbon (SOC) at landscape scale. Information on drivers of SOC dynamics is key for evaluating both soil degradation and SOC stability that can affect soil quality and sustainability. 137Cs measurements provide a very effective tool to infer spatial patterns of soil redistribution and quantify soil redistribution rates in different landscapes, but to date these data are scarce in mountain Mediterranean agroecosystems. We evaluate the effect of soil redistribution on SOC and SOC pools in relation to land use in a Mediterranean mountain catchment (246 ha). To this purpose, two hundred and four soil bulk cores were collected on a 100 m grid in the Estaña lakes catchment located in the central sector of the Spanish Pyrenees (31T 4656250N 295152E). The study area is an agroforestry and endorheic catchment characterized by the presence of evaporite dissolution induced dolines, some of which host permanent lakes. The selected landscape is representative of rainfed areas of Mediterranean continental climate with erodible lithology and shallow soils, and characterized by an intense anthropogenic activity through cultivation and water management. The cultivated and uncultivated areas are heterogeneously distributed. SOC and SOC pools (the active and decomposable fraction, ACF and the stable carbon fraction SCF) were measured by the dry combustion method and soil redistribution rates were derived from 137Cs measurements. The results showed that erosion predominated in the catchment, most of soil samples were identified as eroded sites (n=114) with an average erosion rate of 26.9±51.4 Mg ha-1 y-1 whereas the mean deposition rate was 13.0±24.2 Mg ha-1 y-1. In cultivated soils (n=54) the average of soil erosion rate was significantly higher (78.5±74.4 Mg ha-1 y-1) than in uncultivated soils (6.8±10.4 Mg ha-1 y-1). Similarly, the mean of soil deposition rate in cultivated soils (n=22) was significantly higher (42.6±35.1 Mg ha-1 y-1) than in uncultivated soils (3.4±3.2 Mg ha-1 y-1). The mean SOC content for all soil samples was 2.5±2.0%. In uncultivated soils, significantly higher (P<0.01) amounts of SOC (3.0±2.6%), ACF (2.1±0.7%) and SCF (0.9±0.4%) were found compared to cultivated soils where the means were 1.1±0.7%, 0.7±0.5% and 0.4±0.3%, respectively. Significant (P<0.05) correlations between SOC, SOC pools and soil redistribution rates indicate that the distribution of SOC pools were significantly affected by soil redistribution in the study area. SOC and SOC pools were significantly higher at depositional (n=90, 2.8±1.8%) than at eroded sampling points (2.2±2.1%). ACF shows greater differences at eroding sites and at depositional sites than SCF reflecting that ACF is more sensitive to soil redistribution processes. Our findings emphasize the role of soil redistribution and land use in influencing the dynamics of SOC, information that can be also relevant in soil management. Improving the knowledge on the relationships between land use, soil redistribution processes and SOC fractions is of interest, especially in these Mediterranean rapidly changing landscapes.

Mechanisms underlying the redistribution of particles among the lung's alveolar macrophages during alveolar phase clearance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lehnert, B.E.; Oritz, J.B.; Steinkamp, J.A.

1991-01-01

In order to obtain information about the particle redistribution phenomenon following the deposition of inhaled particles, as well as to obtain information about some of the mechanisms that may be operable in the redistribution of particles, lavaged lung free cell analyses and transmission electron microscopic (TEM) analyses of lung tissue and were performed using lungs from rats after they were subchronically exposed to aerosolized dioxide (TiO{sub 2}). TEM analyses indicated that the in situ autolysis of particle-containing Alveolar Macropages (AM) is one important mechanism involved in the redistribution of particles. Evidence was also obtained that indicated that the engulfment ofmore » one particle-containing phagocyte by another phagocyte also occurs. Another prominent mechanism of the particle redistribution phenomenon may be the in situ proliferation of particle-laden AM. We used the macrophage cell line J774A.1 as a surrogate for AM to investigate how different particulate loads in macrophages may affect their abilities to proliferate. These in vitro investigations indicated that the normal rate of proliferation of macrophages is essentially unaffected by the containment of relatively high particulate burdens. Overall, the results of our investigations suggest that in situ autolysis of particle-containing AM and the rephagocytosis of freed particles by other phagocytes, the phagocytosis of effete and disintegrating particle-containing phagocytes by other AM, and the in situ division of particle-containing AM are likely mechanisms that underlie the post-depositional redistribution of particles among the lung's AM during alveolar phase clearance. 19 refs., 8 figs., 2 tabs.« less

76 FR 62642 - Digital Broadcast Television Redistribution Control; Corrections

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-11

... FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 73 [DA 11-1432] Digital Broadcast Television Redistribution Control; Corrections AGENCY: Federal Communications Commission. ACTION: Technical amendment. SUMMARY: The Federal Communications Commission (FCC) is correcting a final rule that appeared in the...

Subsurface application enhances benefits of manure redistribution

USDA-ARS?s Scientific Manuscript database

Sustainable nutrient management requires redistribution of livestock manure from nutrient-excess areas to nutrient-deficit areas. Field experiments were conducted to assess agronomic (i.e., corn yield) and environmental (i.e., ammonia volatilization and surface nutrient losses) effects of different ...

A simple method for correcting spatially resolved solar intensity oscillation observations for variations in scattered light

NASA Technical Reports Server (NTRS)

Jefferies, S. M.; Duvall, T. L., Jr.

1991-01-01

A measurement of the intensity distribution in an image of the solar disk will be corrupted by a spatial redistribution of the light that is caused by the earth's atmosphere and the observing instrument. A simple correction method is introduced here that is applicable for solar p-mode intensity observations obtained over a period of time in which there is a significant change in the scattering component of the point spread function. The method circumvents the problems incurred with an accurate determination of the spatial point spread function and its subsequent deconvolution from the observations. The method only corrects the spherical harmonic coefficients that represent the spatial frequencies present in the image and does not correct the image itself.

Structural control of nonlinear optical absorption and refraction in dense metal nanoparticle arrays.

PubMed

Kohlgraf-Owens, Dana C; Kik, Pieter G

2009-08-17

The linear and nonlinear optical properties of a composite containing interacting spherical silver nanoparticles embedded in a dielectric host are studied as a function of interparticle separation using three dimensional frequency domain simulations. It is shown that for a fixed amount of metal, the effective third-order nonlinear susceptibility of the composite chi((3))(omega) can be significantly enhanced with respect to the linear optical properties, due to a combination of resonant surface plasmon excitation and local field redistribution. It is shown that this geometry-dependent susceptibility enhancement can lead to an improved figure of merit for nonlinear absorption. Enhancement factors for the nonlinear susceptibility of the composite are calculated, and the complex nature of the enhancement factors is discussed.

Extending the timescale for using beryllium 7 measurements to document soil redistribution by erosion

NASA Astrophysics Data System (ADS)

Walling, D. E.; Schuller, P.; Zhang, Y.; Iroumé, A.

2009-02-01

The need for spatially distributed information on soil mobilization, transfer, and deposition within the landscape by erosion has focused attention on the potential for using fallout radionuclides (i.e., 137Cs, excess 210Pb, and 7Be) to document soil redistribution rates. Whereas 137Cs and excess 210Pb are used to estimate medium- and longer-term erosion rates (i.e., approximately 45 years and 100 years, respectively), 7Be, by virtue of its short half-life (53 days), provides potential for estimating short-term soil redistribution on bare soils. However, the approach commonly used with this radionuclide means that it can only be applied to individual events or short periods of heavy rain. In addition, it is also frequently difficult to ensure that the requirement for spatially uniform 7Be inventories across the study area immediately prior to the study period is met. If the existing approach is applied to longer periods with several rainfall events (e.g., several weeks or more) soil redistribution is likely to be substantially underestimated. These problems limit the potential for using the 7Be approach, particularly in investigations where there is a need to assemble representative information on soil redistribution occurring during the entire wet season. This paper reports the development of a new or refined model for converting radionuclide measurements to estimates of soil redistribution (conversion model) for use with 7Be measurements, which permits much longer periods to be studied. This refined model aims to retain much of the simplicity of the existing approach, but takes account of the temporal distribution of both 7Be fallout and erosion during the study period and of the evolution of the 7Be depth distribution during this period. The approach was successfully tested using 7Be measurements from a study of short-term soil redistribution undertaken within an area of recently harvested forest located near Valdivia in Southern Chile. The study period extended over about 3 months and included the main part of the winter wet season of 2006. The estimates of soil redistribution obtained using the new conversion model were consistent with those obtained from erosion pins deployed within the same study area and were two to three times greater than those obtained using the approach and conversion model employed in existing studies.

Virus fate and transport during recharge using recycled water at a research field site in the Montebello Forebay, Los Angeles County, California, 1997-2000

USGS Publications Warehouse

Anders, Robert; Yanko, William A.; Schroeder, Roy A.; Jackson, James L.

2004-01-01

Total and fecal coliform bacteria distributions in subsurface water samples collected at a research field site in Los Angeles County were found to increase from nondetectable levels immediately before artificial recharge using tertiary-treated municipal wastewater (recycled water). This rapid increase indicates that bacteria can move through the soil with the percolating recycled water over intervals of a few days and vertical and horizontal distances of about 3 meters. This conclusion formed the basis for three field-scale experiments using bacterial viruses (bacteriophage) MS2 and PRD1 as surrogates for human enteric viruses and bromide as a conservative tracer to determine the fate and transport of viruses in recycled water during subsurface transport under actual recharge conditions. The research field site consists of a test basin constructed adjacent to a large recharge facility (spreading grounds) located in the Montebello Forebay of Los Angeles County, California. The soil beneath the test basin is predominantly medium to coarse, moderately sorted, grayish-brown sand. The three tracer experiments were conducted during August 1997, August-September 1998, and August 2000. For each experiment, prepared solutions of bacteriophage and bromide were sprayed on the surface of the water in the test basin and injected, using peristaltic pumps, directly into the feed pipe delivering the recycled water to the test basin. Extensive data were obtained for water samples collected from the test basin itself and from depths of 0.3, 0.6, 1.0, 1.5, 3.0, and 7.6 meters below the bottom of the test basin. The rate of bacteriophage inactivation in the recycled water, independent of any processes occurring in the subsurface, was determined from measurements on water samples from the test basin. Regression analysis of the ratios of bacteriophage to bromide was used to determine the attenuation rates for MS2 and PRD1, defined as the logarithmic reduction in the ratio during each experiment. Although the inactivation rates increased during the third tracer experiment, they were nearly two orders of magnitude less than the attenuation rates. Therefore, adsorption, not inactivation, is the predominant removal mechanism for viruses during artificial recharge. Using the colloid-filtration model, the collision efficiency was determined for both bacteriophage during the second and third field-scale tracer experiments. The collision efficiency confirms that more favorable attachment conditions existed for PRD1, especially during the third tracer experiment. The different collision efficiencies between the second and third tracer experiments possibly were due to changing hydraulic conditions at the research field site during each experiment. The field data suggest that an optimal management scenario might exist to maximize the amount of recycled water that can be applied to the spreading grounds while still maintaining favorable attachment conditions for virus removal and thereby ensuring protection of the ground-water supply.

An Analysis of Rocket Propulsion Testing Costs

NASA Technical Reports Server (NTRS)

Ramirez-Pagan, Carmen P.; Rahman, Shamim A.

2009-01-01

The primary mission at NASA Stennis Space Center (SSC) is rocket propulsion testing. Such testing is generally performed within two arenas: (1) Production testing for certification and acceptance, and (2) Developmental testing for prototype or experimental purposes. The customer base consists of NASA programs, DOD programs, and commercial programs. Resources in place to perform on-site testing include both civil servants and contractor personnel, hardware and software including data acquisition and control, and 6 test stands with a total of 14 test positions/cells. For several business reasons there is the need to augment understanding of the test costs for all the various types of test campaigns. Historical propulsion test data was evaluated and analyzed in many different ways with the intent to find any correlation or statistics that could help produce more reliable and accurate cost estimates and projections. The analytical efforts included timeline trends, statistical curve fitting, average cost per test, cost per test second, test cost timeline, and test cost envelopes. Further, the analytical effort includes examining the test cost from the perspective of thrust level and test article characteristics. Some of the analytical approaches did not produce evidence strong enough for further analysis. Some other analytical approaches yield promising results and are candidates for further development and focused study. Information was organized for into its elements: a Project Profile, Test Cost Timeline, and Cost Envelope. The Project Profile is a snap shot of the project life cycle on a timeline fashion, which includes various statistical analyses. The Test Cost Timeline shows the cumulative average test cost, for each project, at each month where there was test activity. The Test Cost Envelope shows a range of cost for a given number of test(s). The supporting information upon which this study was performed came from diverse sources and thus it was necessary to build several intermediate databases in order to understand, validate, and manipulate data. These intermediate databases (validated historical account of schedule, test activity, and cost) by themselves are of great value and utility. For example, for the Project Profile, we were able to merged schedule, cost, and test activity. This kind of historical account conveys important information about sequence of events, lead time, and opportunities for improvement in future propulsion test projects. The Product Requirement Document (PRD) file is a collection of data extracted from each project PRD (technical characteristics, test requirements, and projection of cost, schedule, and test activity). This information could help expedite the development of future PRD (or equivalent document) on similar projects, and could also, when compared to the actual results, help improve projections around cost and schedule. Also, this file can be sorted by the parameter of interest to perform a visual review of potential common themes or trends. The process of searching, collecting, and validating propulsion test data encountered a lot of difficulties which then led to a set of recommendations for improvement in order to facilitate future data gathering and analysis.

Notch sensitivity and stress redistribution in three ceramic-matrix composites

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mackin, T.J.; He, M.Y.; Evans, A.G.

Fiber-reinforced ceramic-matrix composites (CMCs) depend upon inelastic mechanisms to diffuse stress concentrations associated with holes, notches, and cracks. These mechanisms consist of fiber debonding and pullout, multiple matrix cracking, and shear band formation. In order to understand these effects, experiments have bee conducted on several double-edge-notched CMCs that exhibit different stress redistribution mechanisms. Stresses have been measured an d mechanisms identified by using a combination of methods including X0-ray imaging, edge replication, and thermoelastic analysis. Multiple matrix cracking was found to be the most effective stress redistribution mechanism.

Thermodynamics of cell adhesion. II. Freely mobile repellers.

PubMed Central

Torney, D C; Dembo, M; Bell, G I

1986-01-01

The equilibrium adhesion of a cell or vesicle to a substrate is analyzed in a theoretical model in which two types of mobile molecules in the cell membrane are of interest: receptors that can form bonds with fixed ligands in the substrate and repellers that repel the substrate. If the repulsion between the repeller molecule and substrate is greater than kT, there is substantial redistribution of the repellers from the contact area. Coexisting equilibrium states are observed having comparable free energies (a) with unstretched bonds and repeller redistribution and (b) with stretched bonds and partial redistribution. PMID:3955182

Extensions to decomposition of the redistributive effect of health care finance.

PubMed

Zhong, Hai

2009-10-01

The total redistributive effect (RE) of health-care finance has been decomposed into vertical, horizontal and reranking effects. The vertical effect has been further decomposed into tax rate and tax structure effects. We extend this latter decomposition to the horizontal and reranking components of the RE. We also show how to measure the vertical, horizontal and reranking effects of each component of the redistributive system, allowing analysis of the RE of health-care finance in the context of that system. The methods are illustrated with application to the RE of health-care financing in Canada.

Redistribution spurs growth by using a portfolio effect on risky human capital.

PubMed

Lorenz, Jan; Paetzel, Fabian; Schweitzer, Frank

2013-01-01

We demonstrate by mathematical analysis and systematic computer simulations that redistribution can lead to sustainable growth in a society. In accordance with economic models of risky human capital, we assume that dynamics of human capital is modeled as a multiplicative stochastic process which, in the long run, leads to the destruction of individual human capital. When agents are linked by fully redistributive taxation the situation might turn to individual growth in the long run. We consider that a government collects a proportion of income and reduces it by a fraction as costs for administration (efficiency losses). The remaining public good is equally redistributed to all agents. Sustainable growth is induced by redistribution despite the losses from the random growth process and despite administrative costs. Growth results from a portfolio effect. The findings are verified for three different tax schemes: proportional tax, taking proportionally more from the rich, and proportionally more from the poor. We discuss which of these tax schemes performs better with respect to maximize growth under a fixed rate of administrative costs, and the governmental income. This leads us to general conclusions about governmental decisions, the relation to public good games with free riding, and the function of taxation in a risk-taking society.

Coming full circle: 70 years of chronic lymphocytic leukemia cell redistribution, from glucocorticoids to inhibitors of B-cell receptor signaling

PubMed Central

Montserrat, Emili

2013-01-01

Chronic lymphocytic leukemia (CLL) cells proliferate in pseudofollicles within the lymphatic tissues, where signals from the microenvironment and BCR signaling drive the expansion of the CLL clone. Mobilization of tissue-resident cells into the blood removes CLL cells from this nurturing milieu and sensitizes them to cytotoxic drugs. This concept recently gained momentum after the clinical activity of kinase inhibitors that target BCR signaling (spleen tyrosine kinase, Bruton tyrosine kinase, PI3Kδ inhibitors) was established. Besides antiproliferative activity, these drugs cause CLL cell redistribution with rapid lymph node shrinkage, along with a transient surge in lymphocytosis, before inducing objective remissions. Inactivation of critical CLL homing mechanism (chemokine receptors, adhesion molecules), thwarting tissue retention and recirculation into the tissues, appears to be the basis for this striking clinical activity. This effect of BCR-signaling inhibitors resembles redistribution of CLL cells after glucocorticoids, described as early as in the 1940s. As such, we are witnessing a renaissance of the concept of leukemia cell redistribution in modern CLL therapy. Here, we review the molecular basis of CLL cell trafficking, homing, and redistribution and similarities between old and new drugs affecting these processes. In addition, we outline how these discoveries are changing our understanding of CLL biology and therapy. PMID:23264597

Redistribution Spurs Growth by Using a Portfolio Effect on Risky Human Capital

PubMed Central

Lorenz, Jan; Paetzel, Fabian; Schweitzer, Frank

2013-01-01

We demonstrate by mathematical analysis and systematic computer simulations that redistribution can lead to sustainable growth in a society. In accordance with economic models of risky human capital, we assume that dynamics of human capital is modeled as a multiplicative stochastic process which, in the long run, leads to the destruction of individual human capital. When agents are linked by fully redistributive taxation the situation might turn to individual growth in the long run. We consider that a government collects a proportion of income and reduces it by a fraction as costs for administration (efficiency losses). The remaining public good is equally redistributed to all agents. Sustainable growth is induced by redistribution despite the losses from the random growth process and despite administrative costs. Growth results from a portfolio effect. The findings are verified for three different tax schemes: proportional tax, taking proportionally more from the rich, and proportionally more from the poor. We discuss which of these tax schemes performs better with respect to maximize growth under a fixed rate of administrative costs, and the governmental income. This leads us to general conclusions about governmental decisions, the relation to public good games with free riding, and the function of taxation in a risk-taking society. PMID:23390505

ORBIT modelling of fast particle redistribution induced by sawtooth instability

NASA Astrophysics Data System (ADS)

Kim, Doohyun; Podestà, Mario; Poli, Francesca; Princeton Plasma Physics Laboratory Team

2017-10-01

Initial tests on NSTX-U show that introducing energy selectivity for sawtooth (ST) induced fast ion redistribution improves the agreement between experimental and simulated quantities, e.g. neutron rate. Thus, it is expected that a proper description of the fast particle redistribution due to ST can improve the modelling of ST instability and interpretation of experiments using a transport code. In this work, we use ORBIT code to characterise the redistribution of fast particles. In order to simulate a ST crash, a spatial and temporal displacement is implemented as ξ (ρ , t , θ , ϕ) = ∑ξmn (ρ , t) cos (mθ + nϕ) to produce perturbed magnetic fields from the equilibrium field B-> , δB-> = ∇ × (ξ-> × B->) , which affect the fast particle distribution. From ORBIT simulations, we find suitable amplitudes of ξ for each ST crash to reproduce the experimental results. The comparison of the simulation and the experimental results will be discussed as well as the dependence of fast ion redistribution on fast ion phase space variables (i.e. energy, magnetic moment and toroidal angular momentum). Work supported by the U.S. Department of Energy, Office of Science, Office of Fusion Energy Sciences under Contract Number DE-AC02-09CH11466.

Report: EPA Could Improve Its Redistribution of Superfund Payments to Specific Sites

EPA Pesticide Factsheets

Report #2006-P-00027, July 31, 2006. EPA did not make timely redistributions of Superfund coop agreement, interagency agreement, and small purchase payments from the general site identifier “WQ” to the specific Superfund sites or other site identifiers.

HYDRAULIC REDISTRIBUTION IN THE PACIFIC NORTHWEST: TWEAKING THE SYSTEM

EPA Science Inventory

Hydraulic redistribution (HR) has recently been documented in Pacific Northwest forests, but the controls governing this process and its importance to shallow-rooted species are poorly understood. Our objective in this study was to manipulate the soil-root system to tease apart ...

Redistribution of fluorescently labeled tubulin in the mitotic apparatus of sand dollar eggs and the effects of taxol.

PubMed

Hamaguchi, Y; Toriyama, M; Sakai, H; Hiramoto, Y

1987-02-01

Fluorescently labeled tubulin was quickly incorporated into the mitotic apparatus when injected into a live sand dollar egg. After a rectangular area (1.6 X 16 microns) of the mitotic spindle was photobleached at metaphase or anaphase by the irradiation of a laser microbeam, redistribution of fluorescence was almost complete within 30 sec. The photobleached area did not change in shape during the redistribution. During the period of redistribution, the bleached area moved slightly toward the near pole at metaphase and anaphase (means: 1.6 and 1.8 micron/min, respectively). These results indicate that redistribution was not due to the exchange of tubulin subunits only at the ends of microtubules but to their rapid exchange at sites along the microtubules in the bleached region. Furthermore, treadmilling of tubulin molecules along with the spindle microtubules possibly occurred at the rate of 1.6 micron/min at metaphase. Birefringence of the mitotic apparatus increased with a large increase in both the number and length of astral rays shortly after taxol was injected. However, the microtubules did not all seem to elongate at the same rate but appeared to become equalized in length. Chromosome movement stopped within 60 sec after the injection. Centrospheres became large and the labeled tubulin already incorporated into the centrospheres was excluded from the enlarged centrospheres. Shortly after the labeled tubulin was injected following the injection of taxol, it accumulated in the peripheral region of the centrospheres, suggesting that microtubules first assembled at this region. Fluorescently labeled tubulin in the mitotic apparatus in the egg after injection of taxol was redistributed much more slowly after photobleaching than in uninjected eggs.

Household perceptions towards a redistributive policy across health insurance funds in Tanzania.

PubMed

Chomi, Eunice N; Mujinja, Phares G M; Hansen, Kristian; Kiwara, Angwara D; Enemark, Ulrika

2015-03-15

The Tanzanian health insurance system comprises multiple health insurance funds targeting different population groups but which operate in parallel, with no mechanisms for redistribution across the funds. Establishing such redistributive mechanisms requires public support, which is grounded on the level of solidarity within the country. The aim of this paper is to analyse the perceptions of CHF, NHIF and non-member households towards cross-subsidisation of the poor as an indication of the level of solidarity and acceptance of redistributive mechanisms. This study analyses data collected from a survey of 695 households relating to perceptions of household heads towards cross-subsidisation of the poor to enable them to access health services. Kruskal-Wallis test is used to compare perceptions by membership status. Generalized ordinal logistic regression models are used to identify factors associated with support for cross-subsidisation of the poor. Compared to CHF and NHIF households, non-member households expressed the highest support for subsidised CHF membership for the poor. The odds of expressing support for subsidised CHF membership are higher for NHIF households and non-member households, households that are wealthier, whose household heads have lower education levels, and have sick members. The majority of households support a partial rather than fully subsidised CHF membership for the poor and there were no significant differences by membership status. The odds of expressing willingness to contribute towards subsidised CHF membership are higher for households that are wealthier, with young household heads and have confidence in scheme management. The majority may support a redistributive policy, but there are indications that this support and willingness to contribute to its achievement are influenced by the perceived benefits, amount of subsidy considered, and trust in scheme management. These present important issues for consideration when designing redistributive policies.

Intrahepatic Flow Redistribution in Patients Treated with Radioembolization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Spreafico, Carlo, E-mail: carlo.spreafico@istitutotumori.mi.it; Morosi, Carlo, E-mail: carlo.morosi@istitutotumori.mi.it; Maccauro, Marco, E-mail: marco.maccauro@istitutotumori.mi.it

2015-04-15

IntroductionIn planning Yttrium-90 ({sup 90}Y)-radioembolizations, strategy problems arise in tumours with multiple arterial supplies. We aim to demonstrate that tumours can be treated via one main feeding artery achieving flow redistribution by embolizing accessory vessels.MethodsOne hundred {sup 90}Y-radioembolizations were performed on 90 patients using glass microspheres. In 19 lesions/17 patients, accessory branches were found feeding a minor tumour portion and embolized. In all 17 patients, the assessment of the complete perfusion was obtained by angiography and single photon emission computerized tomography–computerized tomography (SPECT–CT). Dosimetry, toxicity, and tumor response rate of the patients treated after flow redistribution were compared with themore » 83 standard-treated patients. Seventeen lesions in 15 patients with flow redistribution were chosen as target lesions and evaluated according to mRECIST criteria.ResultsIn all patients, the complete tumor perfusion was assessed immediately before radioembolization by angiography in all patients and after the {sup 90}Y-infusion by SPECT–CT in 15 of 17 patients. In the 15 assessable patients, the response rate in their 17 lesions was 3 CR, 8 PR, and 6 SD. Dosimetric and toxicity data, as well tumour response rate, were comparable with the 83 patients with regular vasculature.ConclusionsAll embolization procedures were performed successfully with no complications, and the flow redistribution was obtained in all cases. Results in term of toxicity, median dose administered, and radiological response were comparable with standard radioembolizations. Our findings confirmed the intratumoral flow redistribution after embolizing the accessory arteries, which makes it possible to treat the tumour through its single main feeding artery.« less

CXCR2 inverse agonism detected by arrestin redistribution.

PubMed

Kredel, Simone; Wolff, Michael; Wiedenmann, Jörg; Moepps, Barbara; Nienhaus, G Ulrich; Gierschik, Peter; Kistler, Barbara; Heilker, Ralf

2009-10-01

To study CXCR2 modulated arrestin redistribution, the authors employed arrestin as a fusion protein containing either the Aequorea victoria-derived enhanced green fluorescent protein (EGFP) or a recently developed mutant of eqFP611, a red fluorescent protein derived from Entacmaea quadricolor. This mutant, referred to as RFP611, had earlier been found to assume a dimeric quarternary structure. It was therefore employed in this work as a "tandem" (td) construct for pseudo-monomeric fusion protein labeling. Both arrestin fusion proteins, containing either td-RFP611 (Arr-td-RFP611) or enhanced green fluorescent protein (EGFP; Arr-EGFP), were found to colocalize with internalized fluorescently labeled Gro-alpha a few minutes after Gro-alpha addition. Intriguingly, however, Arr-td-RFP611 and Arr-EGFP displayed distinct cellular distribution patterns in the absence of any CXCR2-activating ligand. Under these conditions, Arr-td-RFP611 showed a largely homogeneous cytosolic distribution, whereas Arr-EGFP segregated, to a large degree, into granular spots. These observations indicate a higher sensitivity of Arr EGFP to the constitutive activity of CXCR2 and, accordingly, an increased arrestin redistribution to coated pits and endocytic vesicles. In support of this interpretation, the authors found the known CXCR2 antagonist Sch527123 to act as an inverse agonist with respect to Arr-EGFP redistribution. The inverse agonistic properties of Sch527123 were confirmed in vitro in a guanine nucleotide binding assay, revealing an IC(50) value similar to that observed for Arr-EGFP redistribution. Thus, the redistribution assay, when based on Arr-EGFP, enables the profiling of antagonistic test compounds with respect to inverse agonism. When based on Arr-td-RFP611, the assay may be employed to study CXCR2 agonism or neutral antagonism.

Dynamics of Soil Organic Carbon and Microbial Biomass Carbon in Relation to Water Erosion and Tillage Erosion

PubMed Central

Xiaojun, Nie; Jianhui, Zhang; Zhengan, Su

2013-01-01

Dynamics of soil organic carbon (SOC) are associated with soil erosion, yet there is a shortage of research concerning the relationship between soil erosion, SOC, and especially microbial biomass carbon (MBC). In this paper, we selected two typical slope landscapes including gentle and steep slopes from the Sichuan Basin, China, and used the 137Cs technique to determine the effects of water erosion and tillage erosion on the dynamics of SOC and MBC. Soil samples for the determination of 137Cs, SOC, MBC and soil particle-size fractions were collected on two types of contrasting hillslopes. 137Cs data revealed that soil loss occurred at upper slope positions of the two landscapes and soil accumulation at the lower slope positions. Soil erosion rates as well as distribution patterns of the <0.002-mm clay shows that water erosion is the major process of soil redistribution in the gentle slope landscape, while tillage erosion acts as the dominant process of soil redistribution in the steep slope landscape. In gentle slope landscapes, both SOC and MBC contents increased downslope and these distribution patterns were closely linked to soil redistribution rates. In steep slope landscapes, only SOC contents increased downslope, dependent on soil redistribution. It is noticeable that MBC/SOC ratios were significantly lower in gentle slope landscapes than in steep slope landscapes, implying that water erosion has a negative effect on the microbial biomass compared with tillage erosion. It is suggested that MBC dynamics are closely associated with soil redistribution by water erosion but independent of that by tillage erosion, while SOC dynamics are influenced by soil redistribution by both water erosion and tillage erosion. PMID:23717530

Migration of cell surface concanavalin A receptors in pulsed electric fields.

PubMed Central

Lin-Liu, S; Adey, W R; Poo, M M

1984-01-01

Concanavalin A (con A) receptors on the surface of cultured Xenopus myoblasts redistributed in response to monopolar, pulsed electric fields. The prefield uniform distribution of the receptors became asymmetrical, and was polarized toward the cathodal pole, in the same way as in DC fields. The extent of asymmetry depended on the duration of field exposure, pulse width (or alternatively, interpulse interval), frequency, and intensity. This relationship was most conveniently expressed by using duty cycle, a quantity determined by both pulse width and frequency. Pulses of average intensity 1.5 V/cm induced detectable asymmetry within 5 min. At the lowest average field intensity used, 0.8 V/cm, significant asymmetry was detected at 150 min. For pulses of high duty cycle (greater than 25%), steady state was reached after 30 min exposure and the steady state asymmetry was dependent on average field intensity. For low duty cycle fields, the time required to reach steady state was prolonged (greater than 50 min). Before reaching a steady state, effectiveness of the pulses, as compared with DC fields of equivalent intensity, was a function of duty cycle. A low duty cycle field (fixed number of pulses at low frequency or long interpulse interval) was less effective than high duty cycle fields or DC. PMID:6743751

Hydraulic redistribution by two semi-arid shrub species: Implications for Sahelianagro-ecosystems

EPA Science Inventory

Hydraulic redistribution is the process of passive water movement from deeper moist soil to shallower dry soil layers using plant roots as conduits. Results from this study indicate that this phenomenon exists among two shrub species (Guiera senegalensis and Piliostigma reticulat...

47 CFR 76.1909 - Redistribution control of unencrypted digital terrestrial broadcast content.

Code of Federal Regulations, 2011 CFR

2011-10-01

... content. Where a multichannel video programming distributor retransmits unencrypted digital terrestrial... 47 Telecommunication 4 2011-10-01 2011-10-01 false Redistribution control of unencrypted digital... (CONTINUED) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Encoding Rules § 76.1909...

Redistribution, Recognition and Representation: Working against Pedagogies of Indifference

ERIC Educational Resources Information Center

Lingard, Bob; Keddie, Amanda

2013-01-01

This paper reports on an Australian government-commissioned research study that documented classroom pedagogies in 24 Queensland schools. The research created the model of "productive pedagogies", which conjoined what Nancy Fraser calls a politics of redistribution, recognition and representation. In this model pedagogies are…

Education, Meritocracy and Redistribution

ERIC Educational Resources Information Center

Souto-Otero, Manuel

2010-01-01

This paper analyses the relationship between education, meritocracy and redistribution. It first questions the meritocratic ideal highlighting how it relates to normative expectations that do not hold fully neither in their logic nor in practice. It then complements the literature on persistent inequalities by focusing on the opportunities for…

HYDRAULIC REDISTRIBUTION OF SOIL WATER: ECOSYSTEM IMPLICATIONS FOR PACIFIC NORTHWEST FORESTS

EPA Science Inventory

The physical process of hydraulic redistribution (HR) is driven by competing soil, tree and atmospheric water potential gradients, and may delay severe water stress for roots and other biota associated with the upper soil profile. We monitored soil moisture characteristics across...

CONTAMINANT REDISTRIBUTION CAN CONFOUND INTERPRETATION OF OIL-SPILL BIOREMEDIATION STUDIES

EPA Science Inventory

The physical redistribution of oil between the inside and outside of experimental plots can affect the results of bioremediation field studies that are conducted on shorelines contaminated by real oil spills. Because untreated oil from the surrounding beach will enter the plot, ...

Electromagnetic Field Redistribution in Metal Nanoparticle on Graphene.

PubMed

Li, Keke; Liu, Anping; Wei, Dapeng; Yu, Keke; Sun, Xiaonan; Yan, Sheng; Huang, Yingzhou

2018-04-25

Benefiting from the induced image charge on metal film, the light energy is confined on a film surface under metal nanoparticle dimer, which is called electromagnetic field redistribution. In this work, electromagnetic field distribution of metal nanoparticle monomer or dimer on graphene is investigated through finite-difference time-domain method. The results point out that the electromagnetic field (EM) redistribution occurs in this nanoparticle/graphene hybrid system at infrared region where light energy could also be confined on a monolayer graphene surface. Surface charge distribution was analyzed using finite element analysis, and surface-enhanced Raman spectrum (SERS) was utilized to verify this phenomenon. Furthermore, the data about dielectric nanoparticle on monolayer graphene demonstrate this EM redistribution is attributed to strong coupling between light-excited surface charge on monolayer graphene and graphene plasmon-induced image charge on dielectric nanoparticle surface. Our work extends the knowledge of monolayer graphene plasmon, which has a wide range of applications in monolayer graphene-related film.

Perfusion lung imaging in the adult respiratory distress syndrome

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pistolesi, M.; Miniati, M.; Di Ricco, G.

1986-07-01

In 29 perfusion lung scans (PLS) of 19 patients with ARDS, 20 of which were obtained within six days from the onset of respiratory symptoms, perfusion abnormalities were the rule. These included focal, nonsegmental defects, mostly peripheral and dorsal, and perfusion redistribution away from the dependent lung zones. PLS were scored for the presence and intensity of perfusion abnormalities and the scores of perfusion redistribution were validated against numerical indices of blood flow distribution per unit lung volume. PLS scores were correlated with arterial blood gas values, hemodynamic parameters, and chest radiographic scores of ARDS. Arterial oxygen tension correlated withmore » the scores of both perfusion defects and redistribution. Perfusion defects correlated better with the radiographic score of ARDS, and perfusion redistribution with PAP and vascular resistance. ARDS patients exhibit peculiar patterns of PLS abnormalities not observed in other disorders. Thus, PLS may help considerably in the detection and evaluation of pulmonary vascular injury in ARDS.« less

Adapting radiotherapy to hypoxic tumours

NASA Astrophysics Data System (ADS)

Malinen, Eirik; Søvik, Åste; Hristov, Dimitre; Bruland, Øyvind S.; Rune Olsen, Dag

2006-10-01

In the current work, the concepts of biologically adapted radiotherapy of hypoxic tumours in a framework encompassing functional tumour imaging, tumour control predictions, inverse treatment planning and intensity modulated radiotherapy (IMRT) were presented. Dynamic contrast enhanced magnetic resonance imaging (DCEMRI) of a spontaneous sarcoma in the nasal region of a dog was employed. The tracer concentration in the tumour was assumed related to the oxygen tension and compared to Eppendorf histograph measurements. Based on the pO2-related images derived from the MR analysis, the tumour was divided into four compartments by a segmentation procedure. DICOM structure sets for IMRT planning could be derived thereof. In order to display the possible advantages of non-uniform tumour doses, dose redistribution among the four tumour compartments was introduced. The dose redistribution was constrained by keeping the average dose to the tumour equal to a conventional target dose. The compartmental doses yielding optimum tumour control probability (TCP) were used as input in an inverse planning system, where the planning basis was the pO2-related tumour images from the MR analysis. Uniform (conventional) and non-uniform IMRT plans were scored both physically and biologically. The consequences of random and systematic errors in the compartmental images were evaluated. The normalized frequency distributions of the tracer concentration and the pO2 Eppendorf measurements were not significantly different. 28% of the tumour had, according to the MR analysis, pO2 values of less than 5 mm Hg. The optimum TCP following a non-uniform dose prescription was about four times higher than that following a uniform dose prescription. The non-uniform IMRT dose distribution resulting from the inverse planning gave a three times higher TCP than that of the uniform distribution. The TCP and the dose-based plan quality depended on IMRT parameters defined in the inverse planning procedure (fields and step-and-shoot intensity levels). Simulated random and systematic errors in the pO2-related images reduced the TCP for the non-uniform dose prescription. In conclusion, improved tumour control of hypoxic tumours by dose redistribution may be expected following hypoxia imaging, tumour control predictions, inverse treatment planning and IMRT.

Societal resilience to hydroclimatic change in the Roman World

NASA Astrophysics Data System (ADS)

Dermody, Brian; van Beek, Rens; Bierkens, Marc; Dekker, Stefan

2016-04-01

The Romans were masters of water resource management. They employed sophisticated irrigation techniques alongside a highly integrated food redistribution system that provided stable food supplies under the variable hydroclimatic regime within the Roman World. However, a number of paleoclimate studies have demonstrated hydroclimatic changes during the Roman Period that exceeded the amplitude and persistence of normal climate variability. In particular, there was a shift from warmer and more stable hydroclimatic conditions in the Roman Warm Period (c.250 BC - 250 AD) to cooler and more variable conditions in Late Roman Period (after c.250 AD). In this study we use a socio-hydrological model of the Roman world to explore the impact of hydroclimatic changes between the Roman Warm Period and Late Roman Period on the Roman food production and redistribution system. We calculate crop yields based on temperature and water resource availability using PC Raster Global Water Balance model (PCR-GLOBWB). PCR-GLOBWB is forced with reanalysis climate fields reflecting reconstructions of Roman Warm Period to the Late Roman climate patterns. Cropland areas and settlement patterns are derived from a database of 14,700 Roman settlement sites and crop suitability maps. We simulate food redistribution using a multi-agent food redistribution network with link weights based on Orbis: The Stanford Geospatial Network of the Roman World. Our analysis indicates a reduction in crop yields during the Late Roman Period compared with the Roman Warm Period owing to cooler temperatures. In addition, our simulations indicate that increased hydroclimatic variability decreased the stability of yields in the Late Roman period. Crop yields in the Western Empire are simulated to have been impacted most by the change in climate owing to cooler average temperatures and greater hydroclimatic variability compared with the Eastern part of the Empire. The food redistribution network was essential to buffer against lower and less stable yields in the Late Roman Period. However, the Late Roman Period coincided with a breakdown in the food redistribution network, making the Western Roman Empire particularly vulnerable to changing climate conditions. Our analysis demonstrates a number of important processes that have general implications for water resource management in food production and redistribution systems.

Band structures in a two-dimensional phononic crystal with rotational multiple scatterers

NASA Astrophysics Data System (ADS)

Song, Ailing; Wang, Xiaopeng; Chen, Tianning; Wan, Lele

2017-03-01

In this paper, the acoustic wave propagation in a two-dimensional phononic crystal composed of rotational multiple scatterers is investigated. The dispersion relationships, the transmission spectra and the acoustic modes are calculated by using finite element method. In contrast to the system composed of square tubes, there exist a low-frequency resonant bandgap and two wide Bragg bandgaps in the proposed structure, and the transmission spectra coincide with band structures. Specially, the first bandgap is based on locally resonant mechanism, and the simulation results agree well with the results of electrical circuit analogy. Additionally, increasing the rotation angle can remarkably influence the band structures due to the transfer of sound pressure between the internal and external cavities in low-order modes, and the redistribution of sound pressure in high-order modes. Wider bandgaps are obtained in arrays composed of finite unit cells with different rotation angles. The analysis results provide a good reference for tuning and obtaining wide bandgaps, and hence exploring the potential applications of the proposed phononic crystal in low-frequency noise insulation.

Effects of hiking pole inertia on energy and muscular costs during uphill walking.

PubMed

Foissac, Matthieu J; Berthollet, Romain; Seux, Julien; Belli, Alain; Millet, Guillaume Y

2008-06-01

The purpose of the present study was to investigate the effects of using hiking poles with different inertia on oxygen cost (V O2) and muscular activity. Eleven subjects walked at 3 km.h on a treadmill inclined at 20% grade. Three mass (240, 300, and 360 g), load distribution, and walking frequency (preferred, -20% and +20%) conditions were tested. Each subject also walked without poles and carried a 360-g mass. V[spacing dot above]O2 and average EMG (aEMG) of nine muscles from lower (soleus, gastrocnemius lateralis, vastus lateralis, biceps femoris, gluteus maximus) and upper (latissimus dorsi, biceps brachii, triceps brachii, and anterior deltoid) limbs were recorded. Using poles significantly reduced lower limb muscle aEMG values (P < 0.001) by about 15% and increased upper limb muscle aEMG values (P < 0.001) by about 95%. Hand-masses of 360 g did not result in an increased V[spacing dot above]O2, and the only modification in terms of muscular activation was greater biceps brachii activity (+55%, P = 0.006). Biceps brachii and anterior deltoid activity were also influenced by pole mass and load distribution (P < 0.01). Walking at high frequency increased both aEMG and V[spacing dot above]O2, whereas walking at low frequency redistributed the muscular work from the thigh muscles to calf and upper limb muscles although this did not lead to an increased V[spacing dot above]O2 compared with that at preferred frequency. No interaction between mass and frequency was found for aEMG or V[spacing dot above]O2. Using poles and changing frequency have important effects on muscle recruitment, whereas the effects of mass were limited when considering poles available on the market.

Kerr optical frequency combs: theory, applications and perspectives

NASA Astrophysics Data System (ADS)

Chembo, Yanne K.

2016-06-01

The optical frequency comb technology is one of the most important breakthrough in photonics in recent years. This concept has revolutionized the science of ultra-stable lightwave and microwave signal generation. These combs were originally generated using ultrafast mode-locked lasers, but in the past decade, a simple and elegant alternativewas proposed,which consisted in pumping an ultra-high-Q optical resonator with Kerr nonlinearity using a continuous-wave laser. When optimal conditions are met, the intracavity pump photons are redistributed via four-wave mixing to the neighboring cavity modes, thereby creating the so-called Kerr optical frequency comb. Beyond being energy-efficient, conceptually simple, and structurally robust, Kerr comb generators are very compact devices (millimetric down to micrometric size) which can be integrated on a chip. They are, therefore, considered as very promising candidates to replace femtosecond mode-locked lasers for the generation of broadband and coherent optical frequency combs in the spectral domain, or equivalently, narrow optical pulses in the temporal domain. These combs are, moreover, expected to provide breakthroughs in many technological areas, such as integrated photonics, metrology, optical telecommunications, and aerospace engineering. The purpose of this review article is to present a comprehensive survey of the topic of Kerr optical frequency combs.We provide an overview of the main theoretical and experimental results that have been obtained so far. We also highlight the potential of Kerr combs for current or prospective applications, and discuss as well some of the open challenges that are to be met at the fundamental and applied level.

Estimation of representative elementary volume for DNAPL saturation and DNAPL-water interfacial areas in 2D heterogeneous porous media

NASA Astrophysics Data System (ADS)

Wu, Ming; Cheng, Zhou; Wu, Jianfeng; Wu, Jichun

2017-06-01

Representative elementary volume (REV) is important to determine properties of porous media and those involved in migration of contaminants especially dense nonaqueous phase liquids (DNAPLs) in subsurface environment. In this study, an experiment of long-term migration of the commonly used DNAPL, perchloroethylene (PCE), is performed in a two dimensional (2D) sandbox where several system variables including porosity, PCE saturation (Soil) and PCE-water interfacial area (AOW) are accurately quantified by light transmission techniques over the entire PCE migration process. Moreover, the REVs for these system variables are estimated by a criterion of relative gradient error (εgi) and results indicate that the frequency of minimum porosity-REV size closely follows a Gaussian distribution in the range of 2.0 mm and 8.0 mm. As experiment proceeds in PCE infiltration process, the frequency and cumulative frequency of both minimum Soil-REV and minimum AOW-REV sizes change their shapes from the irregular and random to the regular and smooth. When experiment comes into redistribution process, the cumulative frequency of minimum Soil-REV size reveals a linear positive correlation, while frequency of minimum AOW-REV size tends to a Gaussian distribution in the range of 2.0 mm-7.0 mm and appears a peak value in 13.0 mm-14.0 mm. Undoubtedly, this study will facilitate the quantification of REVs for materials and fluid properties in a rapid, handy and economical manner, which helps enhance our understanding of porous media and DNAPL properties at micro scale, as well as the accuracy of DNAPL contamination modeling at field-scale.

A Mathematical Model on Water Redistribution Mechanism of the Seismonastic Movement of Mimosa Pudica

PubMed Central

Kwan, K.W.; Ye, Z.W.; Chye, M.L.; Ngan, A.H.W.

2013-01-01

A theoretical model based on the water redistribution mechanism is proposed to predict the volumetric strain of motor cells in Mimosa pudica during the seismonastic movement. The model describes the water and ion movements following the opening of ion channels triggered by stimulation. The cellular strain is related to the angular velocity of the plant movement, and both their predictions are in good agreement with experimental data, thus validating the water redistribution mechanism. The results reveal that an increase in ion diffusivity across the cell membrane of <15-fold is sufficient to produce the observed seismonastic movement. PMID:23823246

Anthropogenic radionuclides for estimating rates of soil redistribution by wind

USDA-ARS?s Scientific Manuscript database

Erosion of soil by wind and water is a degrading process that affects millions of hectares worldwide. Atmospheric testing of nuclear weapons and the resulting fallout of anthropogenic radioisotopes, particularly Cesium 137, has made possible the estimation of mean soil redistribution rates. The pe...

Anthropogenic radioisotopes to estimate rates of soil redistribution by wind

USDA-ARS?s Scientific Manuscript database

Erosion of soil by wind and water is a degrading process that affects millions of hectares worldwide. Atmospheric testing of nuclear weapons and the resulting fallout of anthropogenic radioisotopes, particularly Cesium 137, has made possible the estimation of mean soil redistribution rates. The pe...

HYDRAULIC REDISTRIBUTION IN A DOUGLAS-FIR FOREST: LESSONS FROM SYSTEM MANIPULATIONS

EPA Science Inventory

Hydraulic redistribution (HR) has been shown to slow drying of surface soils during drought in Pacific Northwest forests, but the controls governing this process and its importance to shallow-rooted species are poorly understood. Our objective in this study was to manipulate the...

HYDRAULIC REDISTRIBUTION IN A DOUGLAS-FIR FOREST: LESSONS FROM SYSTEM MANIPULATIONS

EPA Science Inventory

Hydraulic redistribution (HR) occurs in many ecosystems; however, key questions remain about its consequences at the ecosystem level. The objectives of the present study were to quantify seasonal variation in HR and its driving force, and to manipulate the soil-root system to e...

Modelling evolution of air dose rates in river basins in Fukushima Prefecture affected by sediment-sorbed radiocesium redistribution

NASA Astrophysics Data System (ADS)

Malins, A.; Sakuma, K.; Nakanishi, T.; Kurikami, H.; Machida, M.; Kitamura, A.; Yamada, S.

2015-12-01

The radioactive 134Cs and 137Cs isotopes deposited over Fukushima Prefecture by the Fukushima Daiichi nuclear disaster are the predominant radiological concern for the years following the accident. This is because the energetic gamma radiation they emit on decay constitutes the majority of the elevated air dose rates that now afflict the region. Therefore, we developed a tool for calculating air dose rates from arbitrary radiocesium spatial distributions across the land surface and depth profiles within the ground. As cesium is strongly absorbed by clay soils, its primary redistribution mechanism within Fukushima Prefecture is by soil erosion and water-borne sediment transport. Each year between 0.1~1% of the total radiocesium inventory in the river basins neighboring Fukushima Daiichi is eroded from the land surface and enters into water courses, predominantly during typhoon storms. Although this is a small amount in relative terms, in absolute terms it corresponds to terabecquerels of 134Cs and 137Cs redistribution each year and this can affect the air dose rate at locations of high erosion and sediment deposition. This study inputs the results of sediment redistribution simulations into the dose rate evaluation tool to calculate the locations and magnitude of air dose rate changes due to radiocesium redistribution. The dose rate calculations are supported by handheld survey instrument results taken within the Prefecture.

Mass Redistribution in the Core and Time-varying Gravity at the Earth's Surface

NASA Technical Reports Server (NTRS)

Kuang, Wei-Jia; Chao, Benjamin F.; Fang, Ming

2003-01-01

The Earth's liquid outer core is in convection, as suggested by the existence of the geomagnetic field in much of the Earth's history. One consequence of the convection is the redistribution of mass resulting from relative motion among fluid parcels with slightly different densities. This time dependent mass redistribution inside the core produces a small perturbation on the gravity field of the Earth. With our numerical dynamo solutions, we find that the mass redistribution (and the resultant gravity field) symmetric about the equator is much stronger than that anti-symmetric about the equator. In particular, J(sub 2) component is the strongest. In addition, the gravity field variation increases with the Rayleigh number that measures the driving force for the geodynamo in the core. With reasonable scaling from the current dynamo solutions, we could expect that at the surface of the Earth, the J(sub 2) variation from the core is on the order of l0(exp -16)/year relative to the mean (i.e. spherically symmetric) gravity field of the Earth. The possible shielding effect due to core-mantle boundary pressure variation loading is likely much smaller and is therefore negligible. Our results suggest that time-varying gravity field perturbation due to core mass redistribution may be measured with modem space geodetic observations, which will result a new means of detecting dynamical processes in the Earth's deep interior.