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

Saji, Chiaki; Higashi, Chizuka; Niinaka, Yasufumi

Highlights: Black-Right-Pointing-Pointer Constitutive NF-{kappa}B signaling is essential for the survival and growth of PEL cells. Black-Right-Pointing-Pointer NF-{kappa}B signaling is upregulated by the proteasome-dependent degradation of I{kappa}B{alpha}. Black-Right-Pointing-Pointer Proteasome inhibitors suppress NF-{kappa}B signaling and induce apoptosis in PEL cells through stabilization of I{kappa}B{alpha}. Black-Right-Pointing-Pointer Proteasome inhibitors suppress viral replication in PEL cells during lytic KSHV infection. -- Abstract: Primary effusion lymphoma (PEL) is an aggressive neoplasm caused by Kaposi's sarcoma-associated herpesvirus (KSHV). This study provides evidence that proteasomal activity is required for both survival of PEL cells stably harboring the KSHV genome and viral replication of KSHV. We evaluated the cytotoxicmore » effects of proteasome inhibitors on PEL cells. The proteasome inhibitors MG132, lactacystin, and proteasome inhibitor I dramatically inhibited cell proliferation and induced apoptosis of PEL cells through the accumulation of p21 and p27. Furthermore, proteasome inhibitors induced the stabilization of NF-{kappa}B inhibitory molecule (I{kappa}B{alpha}) and suppressed the transcriptional activity of NF-{kappa}B in PEL cells. The NF-{kappa}B specific inhibitor BAY11-7082 also induced apoptosis in PEL cells. The constitutive activation of NF-{kappa}B signaling is essential for the survival and growth of B cell lymphoma cells, including PEL cells. NF-{kappa}B signaling is upregulated by proteasome-dependent degradation of I{kappa}B{alpha}. The suppression of NF-{kappa}B signaling by proteasome inhibitors may contribute to the induction of apoptosis in PEL cells. In addition, proteasome activity is required for KSHV replication in KSHV latently infected PEL cells. MG132 reduced the production of progeny virus from PEL cells at low concentrations, which do not affect PEL cell growth. These findings suggest that proteasome inhibitors may represent a novel strategy for the treatment of KSHV infection and KSHV-associated lymphomas.« less

Biofilm Formation by the Acidophile Bacterium Acidithiobacillus thiooxidans Involves c-di-GMP Pathway and Pel exopolysaccharide.

PubMed

Díaz, Mauricio; Castro, Matias; Copaja, Sylvia; Guiliani, Nicolas

2018-02-21

Acidophile bacteria belonging to the Acidithiobacillus genus are pivotal players for the bioleaching of metallic values such as copper. Cell adherence to ores and biofilm formation, mediated by the production of extracellular polymeric substances, strongly favors bioleaching activity. In recent years, the second messenger cyclic diguanylate (c-di-GMP) has emerged as a central regulator for biofilm formation in bacteria. C-di-GMP pathways have been reported in different Acidithiobacillus species; however, c-di-GMP effectors and signal transduction networks are still largely uncharacterized in these extremophile species. Here we investigated Pel exopolysaccharide and its role in biofilm formation by sulfur-oxidizing species Acidithiobacillus thiooxidans . We identified 39 open reading frames (ORFs) encoding proteins involved in c-di-GMP metabolism and signal transduction, including the c-di-GMP effector protein PelD, a structural component of the biosynthesis apparatus for Pel exopolysaccharide production. We found that intracellular c-di-GMP concentrations and transcription levels of pel genes were higher in At . thiooxidans biofilm cells compared to planktonic ones. By developing an At . thiooxidans Δ pelD null-mutant strain we revealed that Pel exopolysaccharide is involved in biofilm structure and development. Further studies are still necessary to understand how Pel biosynthesis is regulated in Acidithiobacillus species, nevertheless these results represent the first characterization of a c-di-GMP effector protein involved in biofilm formation by acidophile species.

Derivation of an occupational exposure limit (OEL) for methylene chloride based on acute CNS effects and relative potency analysis.

PubMed

Storm, J E; Rozman, K K

1998-06-01

The Occupational Safety and Health Administration (OSHA) methylene chloride Permissible Exposure Level (PEL) or 25 ppm is quantitatively derived from mouse tumor results observed in a high-exposure National Toxicology Program bioassay. Because this approach depends on controversial interspecies and low-dose extrapolations, the PEL itself has stimulated heated debate. Here, an alternative safety assessment for methylene chloride is presented. It is based on an acute human lowest-observed-adverse-effect level (LOAEL) of 200 ppm for subtle central nervous system (CNS) depression. Steep, parallel exposure-response curves for anesthetic and subanesthetic CNS effects associated with compounds mechanistically and structurally related to methylene chloride are shown to support a safety factor of two to account for inter-individual variability in response. LOAEL/no-observed-adverse-effect ratios for subtle CNS effects associated with structurally related solvents are shown to support a safety factor range of two to four to account for uncertainty in identifying a subthreshold exposure level. Anesthetic relative potencies and anesthetic/subanesthetic effect level ratios are shown to be constant for the compounds evaluated, demonstrating that subanesthetic relative potencies are also constant. Relative potencies among similarly derived occupational exposure limits (OELs) for solvents structurally related to methylene chloride are therefore used to validate the derived methylene chloride OEL range of 25-50 ppm. Because this safety assessment is based on human (rather than rodent) data and empirical (rather than theoretical) exposure-response relationships and is supported by relative potency analysis, it is a defensible alternative to to the OSHA risk assessment and should positively contribute to the debate regarding the appropriate basis and value for a methylene chloride PEL.

A preclustering-based ensemble learning technique for acute appendicitis diagnoses.

PubMed

Lee, Yen-Hsien; Hu, Paul Jen-Hwa; Cheng, Tsang-Hsiang; Huang, Te-Chia; Chuang, Wei-Yao

2013-06-01

Acute appendicitis is a common medical condition, whose effective, timely diagnosis can be difficult. A missed diagnosis not only puts the patient in danger but also requires additional resources for corrective treatments. An acute appendicitis diagnosis constitutes a classification problem, for which a further fundamental challenge pertains to the skewed outcome class distribution of instances in the training sample. A preclustering-based ensemble learning (PEL) technique aims to address the associated imbalanced sample learning problems and thereby support the timely, accurate diagnosis of acute appendicitis. The proposed PEL technique employs undersampling to reduce the number of majority-class instances in a training sample, uses preclustering to group similar majority-class instances into multiple groups, and selects from each group representative instances to create more balanced samples. The PEL technique thereby reduces potential information loss from random undersampling. It also takes advantage of ensemble learning to improve performance. We empirically evaluate this proposed technique with 574 clinical cases obtained from a comprehensive tertiary hospital in southern Taiwan, using several prevalent techniques and a salient scoring system as benchmarks. The comparative results show that PEL is more effective and less biased than any benchmarks. The proposed PEL technique seems more sensitive to identifying positive acute appendicitis than the commonly used Alvarado scoring system and exhibits higher specificity in identifying negative acute appendicitis. In addition, the sensitivity and specificity values of PEL appear higher than those of the investigated benchmarks that follow the resampling approach. Our analysis suggests PEL benefits from the more representative majority-class instances in the training sample. According to our overall evaluation results, PEL records the best overall performance, and its area under the curve measure reaches 0.619. The PEL technique is capable of addressing imbalanced sample learning associated with acute appendicitis diagnosis. Our evaluation results suggest PEL is less biased toward a positive or negative class than the investigated benchmark techniques. In addition, our results indicate the overall effectiveness of the proposed technique, compared with prevalent scoring systems or salient classification techniques that follow the resampling approach. Copyright © 2013 Elsevier B.V. All rights reserved.

The Association between Cardiovascular Disease Risk and Parental Educational Level in Portuguese Children

PubMed Central

Duncan, Michael J.; Vale, Susana; Santos, Maria Paula; Ribeiro, José Carlos; Mota, Jorge

2012-01-01

The aim of this study was to examine any differences in cardiovascular disease (CVD) risk in Portuguese children split by parental educational level. A cross-sectional school-based study was conducted in 2011 on 359 Portuguese children (202 girls and 157 boys) aged 10 to 17 years (mean age ± SD = 13.9 ± 1.98 years). Height and body mass were assessed to determine body mass index (BMI). Parental education level (PEL) was used as a surrogate for socioeconomic status (SES). Capillary blood sampling was used to determine: Total Cholesterol (TC), Triglycerides (TG), Fasting Glucos (GLUC), High and Low Density Lipoprotein (HDL/LDL). These measurements were combined with measures of systolic blood pressure and cardiorespiratory fitness as z-scores. CVD risk was constructed by summing the z-scores. Analysis of covariance, controlling for BMI, indicated that CVD risk was significantly different across PEL groups (p = 0.01), with CVD risk score being significantly lower in low (p = 0.04) and middle (p = 0.008) PEL groups, compared to high PEL. Moreover, the covariate, BMI was also significant (p = 0.0001, β = 0.023), evidencing a significant positive association between BMI and CVD risk, with higher BMI associated with greater CVD risk. In Portuguese children, significantly greater CVD risk was found for children of high PEL, while higher BMI was associated with greater CVD risk. PMID:23330223

Cooperative roles for emmprin and LYVE-1 in the regulation of chemoresistance for primary effusion lymphoma

PubMed Central

Qin, Z; Dai, L; Bratoeva, M; Slomiany, MG; Toole, BP; Parsons, C

2013-01-01

The Kaposi’s sarcoma-associated herpesvirus is the causative agent of primary effusion lymphoma (PEL), for which cytotoxic chemotherapy represents the standard of care. The high mortality associated with PEL may be explained in part by resistance of these tumors to chemotherapy. The membrane-bound glycoprotein emmprin (CD147) enhances chemoresistance in tumors through effects on transporter expression, trafficking and interactions. Interactions between hyaluronan and hyaluronan receptors on the cell surface also facilitate emmprin-mediated chemoresistance. Whether emmprin or hyaluronan-receptor interactions regulate chemotherapeutic resistance for virus-associated malignancies is unknown. Using human PEL tumor cells, we found that PEL sensitivity to chemotherapy is directly proportional to expression of emmprin, the lymphatic vessel endothelial hyaluronan receptor-1 (LYVE-1) and a drug transporter known as the breast cancer resistance protein/ABCG2 (BCRP), and that emmprin, LYVE-1 and BCRP interact with each other and colocalize on the PEL cell surface. In addition, we found that emmprin induces chemoresistance in PEL cells through upregulation of BCRP expression, and RNA interference targeting of emmprin, LYVE-1 or BCRP enhances PEL cell apoptosis induced by chemotherapy. Finally, disruption of hyaluronan-receptor interactions using small hyaluronan oligosaccharides reduces expression of emmprin and BCRP while sensitizing PEL cells to chemotherapy. Collectively, these data support interdependent roles for emmprin, LYVE-1 and BCRP in chemotherapeutic resistance for PEL. PMID:21660043

Antitumor activity of the synthetic retinoid ST1926 on primary effusion lymphoma in vitro and in vivo models.

PubMed

Karam, Louna; Houshaymi, Bilal; Abdel-Samad, Rana; Jaafar, Mariam; Halloum, Iman; Pisano, Claudio; Neipel, Frank; Darwiche, Nadine; Abou Merhi, Raghida

2018-02-01

Primary effusion lymphoma (PEL) is a rare B-cell neoplasm, associated with Kaposi sarcoma-associated herpes virus/human herpes virus-8 (KSHV/HHV-8), arising as malignant effusions in body cavities. PEL cells do not harbor conventional genetic cancer mutations; however, their oncogenesis is mainly attributed to HHV-8 latent genes. Treatment strategies are inefficient resulting in poor prognosis of PEL patients, stressing the need for new effective therapy. ST1926 is a synthetic retinoid with favorable antitumor properties and no cross-resistance with the natural retinoid, all-trans retinoic acid. ST1926 has shown potent apoptotic activities on a variety of solid tumors and hematologic malignancies in in vitro and in vivo models. In the present study we elucidated the antitumor activities and underlying molecular mechanism of ST1926 using in vitro, ex vivo, and in vivo PEL preclinical models. ST1926, at sub‑micromolar concentrations, displayed potent antiproliferative effects on PEL cell lines and malignant ascites. Furthermore, ST1926 treatment of PEL cells and ascites resulted in their accumulation in the sub-G1 region, S phase cell cycle arrest, early DNA damage, PARP cleavage and p53 activation including the upregulation of its target genes p21 and Bax. However, ST1926 did not significantly modulate HHV-8 latent viral transcripts. Importantly, ST1926 delayed formation of ascites and enhanced survival of PEL mice. These results highlight the therapeutic potential of ST1926 in combination with drugs that target HHV-8 in PEL patients.

Up-regulation of tumor suppressor genes by exogenous dhC16-Cer contributes to its anti-cancer activity in primary effusion lymphoma.

PubMed

Cao, Yueyu; Qiao, Jing; Lin, Zhen; Zabaleta, Jovanny; Dai, Lu; Qin, Zhiqiang

2017-02-28

Primary effusion lymphoma (PEL) is a rare and highly aggressive B-cell malignancy with Kaposi's sarcoma-associated herpesvirus (KSHV) infection, while lack of effective therapies. Our recent data indicated that targeting the sphingolipid metabolism by either sphingosine kinase inhibitor or exogenous ceramide species induces PEL cell apoptosis and suppresses tumor progression in vivo. However, the underlying mechanisms for these exogenous ceramides "killing" PEL cells remain largely unknown. Based on the microarray analysis, we found that exogenous dhC16-Cer treatment affected the expression of many cellular genes with important functions within PEL cells such as regulation of cell cycle, cell survival/proliferation, and apoptosis/anti-apoptosis. Interestingly, we found that a subset of tumor suppressor genes (TSGs) was up-regulated from dhC16-Cer treated PEL cells. One of these elevated TSGs, Thrombospondin-1 (THBS1) was required for dhC16-Cer induced PEL cell cycle arrest. Moreover, dhC16-Cer up-regulation of THBS1 was through the suppression of multiple KSHV microRNAs expression. Our data demonstrate that exogenous ceramides display anti-cancer activities for PEL through regulation of both host and oncogenic virus factors.

Pectate lyase PelI of Erwinia chrysanthemi 3937 belongs to a new family.

PubMed Central

Shevchik, V E; Robert-Baudouy, J; Hugouvieux-Cotte-Pattat, N

1997-01-01

Erwinia chrysanthemi 3937 secretes five major isoenzymes of pectate lyases encoded by the pel4, pelB, pelC, pelD, and pelE genes and a set of secondary pectate lyases, two of which, pelL and pelZ, have been already identified. We cloned the pelI gene, encoding a ninth pectate lyase of E. chrysanthemi 3937. The pelI reading frame is 1,035 bases long, corresponding to a protein of 344 amino acids including a typical amino-terminal signal sequence of 19 amino acids. The purified mature PelI protein has an isoelectric point of about 9 and an apparent molecular mass of 34 kDa. PelI has a preference for partially methyl esterified pectin and presents an endo-cleaving activity with an alkaline pH optimum and an absolute requirement for Ca2+ ions. PelI is an extracellular protein secreted by the Out secretory pathway of E. chrysanthemi. The PelI protein is very active in the maceration of plant tissues. A pelI mutant displayed reduced pathogenicity on chicory leaves, but its virulence did not appear to be affected on potato tubers or Saintpaulia ionantha plants. The pelI gene constitutes an independent transcriptional unit. As shown for the other pel genes, the transcription of pelI is dependent on various environmental conditions. It is induced by pectic catabolic products and affected by growth phase, oxygen limitation, temperature, nitrogen starvation, and catabolite repression. Regulation of pelI expression appeared to be dependent on the three repressors of pectinase synthesis, KdgR, PecS, and PecT, and on the global activator of sugar catabolism, cyclic AMP receptor protein. A functional KdgR binding site was identified close to the putative pelI promoter. Analysis of the amino acid sequence of PelI revealed high homology with a pectate lyase from Erwinia carotovora subsp. carotovora (65% identity) and low homology with pectate lyases of the phytopathogenic fungus Nectria haematococca (Fusarium solani). This finding indicates that PelI belongs to pectate lyase class III. Using immunoblotting experiments, we detected PelI homologs in various strains of E. chrysanthemi and E. carotovora subsp. carotovora but not in E. carotovora subsp. atroseptica. PMID:9393696

Antidepressant-like effect of food-derived pyroglutamyl peptides in mice.

PubMed

Yamamoto, Yukako; Mizushige, Takafumi; Mori, Yukiha; Shimmura, Yuki; Fukutomi, Ruuta; Kanamoto, Ryuhei; Ohinata, Kousaku

2015-06-01

The N-terminal glutamine residue, exposed by enzymatic cleavage of precursor proteins, is known to be modified to a pyroglutamyl residue with a cyclic structure in not only endogenous but also food-derived peptides. We investigated the effects of wheat-derived pyroglutamyl peptides on emotional behaviors. Pyroglutamyl leucine (pyroGlu-Leu, pEL) and pyroglutamyl glutaminyl leucine (pyroGlu-Gln-Leu, pEQL) exhibited antidepressant-like activity in the tail suspension and forced swim tests in mice. pEQL exhibited more potent antidepressant-like activity than pEL after i.p. and i.c.v. administration. pEQL exhibited antidepressant-like activity at a lower dose than Gln-Gln-Leu, suggesting that pyroglutamyl peptide had more potent activity. To examine whether pyroglutamyl peptides increased hippocampus neurogenesis, associated with the effects of antidepressants, we measured 5-bromo-2'-deoxyuridine (BrdU) incorporation. pEL and pEQL increased BrdU-positive cells in the dentate gyrus of the hippocampus. Intriguingly, pEL did not increase hippocampal mRNA and protein expression of brain-derived neurotrophic factor (BDNF), which is a factor associated with both neuropoietic and antidepressive effects. Thus, pyroglutamyl peptides may enhance hippocampal neurogenesis via a pathway independent of BDNF. We also confirmed that pEL and pEQL were produced in the subtilisin digest of major wheat proteins, glutenin and gliadin, after heat treatment. pEL and pEQL are the first peptides derived from wheat proteins to be shown to exhibit an antidepressant-like activity. Copyright © 2015 Elsevier Ltd. All rights reserved.

Up-regulation of tumor suppressor genes by exogenous dhC16-Cer contributes to its anti-cancer activity in primary effusion lymphoma

PubMed Central

Lin, Zhen; Zabaleta, Jovanny; Dai, Lu; Qin, Zhiqiang

2017-01-01

Primary effusion lymphoma (PEL) is a rare and highly aggressive B-cell malignancy with Kaposi's sarcoma-associated herpesvirus (KSHV) infection, while lack of effective therapies. Our recent data indicated that targeting the sphingolipid metabolism by either sphingosine kinase inhibitor or exogenous ceramide species induces PEL cell apoptosis and suppresses tumor progression in vivo. However, the underlying mechanisms for these exogenous ceramides “killing” PEL cells remain largely unknown. Based on the microarray analysis, we found that exogenous dhC16-Cer treatment affected the expression of many cellular genes with important functions within PEL cells such as regulation of cell cycle, cell survival/proliferation, and apoptosis/anti-apoptosis. Interestingly, we found that a subset of tumor suppressor genes (TSGs) was up-regulated from dhC16-Cer treated PEL cells. One of these elevated TSGs, Thrombospondin-1 (THBS1) was required for dhC16-Cer induced PEL cell cycle arrest. Moreover, dhC16-Cer up-regulation of THBS1 was through the suppression of multiple KSHV microRNAs expression. Our data demonstrate that exogenous ceramides display anti-cancer activities for PEL through regulation of both host and oncogenic virus factors. PMID:28146424

Triptolide inhibits transcription of hTERT through down-regulation of transcription factor specificity protein 1 in primary effusion lymphoma cells

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

Long, Cong; Wang, Jingchao; Guo, Wei

Primary effusion lymphoma (PEL) is a rare and aggressive non-Hodgkin's lymphoma. Human telomerase reverse transcriptase (hTERT), a key component responsible for the regulation of telomerase activity, plays important roles in cellular immortalization and cancer development. Triptolide purified from Tripterygium extracts displays a broad-spectrum bioactivity profile, including immunosuppressive, anti-inflammatory, and anti-tumor. In this study, it is investigated whether triptolide reduces hTERT expression and suppresses its activity in PEL cells. The mRNA and protein levels of hTERT were examined by real time-PCR and Western blotting, respectively. The activity of hTERT promoter was determined by Dual luciferase reporter assay. Our results demonstrated thatmore » triptolide decreased expression of hTERT at both mRNA and protein levels. Further gene sequence analysis indicated that the activity of hTERT promoter was suppressed by triptolide. Triptolide also reduced the half-time of hTERT. Additionally, triptolide inhibited the expression of transcription factor specificity protein 1(Sp1) in PEL cells. Furthermore, knock-down of Sp1 by using specific shRNAs resulted in down-regulation of hTERT transcription and protein expression levels. Inhibition of Sp1 by specific shRNAs enhanced triptolide-induced cell growth inhibition and apoptosis. Collectively, our results demonstrate that the inhibitory effect of triptolide on hTERT transcription is possibly mediated by inhibition of transcription factor Sp1 in PEL cells. - Highlights: • Triptolide reduces expression of hTERT by decreasing its transcription level. • Triptolide reduces promoter activity and stability of hTERT. • Triptolide down-regulates expression of Sp1. • Special Sp1 shRNAs inhibit transcription and protein expression of hTERT. • Triptolide and Sp1 shRNA2 induce cell proliferation inhibition and apoptosis.« less

Cloning, expression and characterization of a pectate lyase from Paenibacillus sp. 0602 in recombinant Escherichia coli

PubMed Central

2014-01-01

Background Biotechnological applications of microbial pectate lyases (Pels) in plant fiber processing are considered as environmentally friendly. As such, they become promising substitutes for conventional chemical degumming process. Since applications of Pels in various fields are widening, it is necessary to explore new pectolytic microorganisms and enzymes for efficient and effective usage. Here, we describe the cloning, expression, characterization and application of the recombinant Pel protein from a pectolytic bacterium of the genus Paenibacillus in Escherichia coli. Results A Pel gene (pelN) was cloned using degenerate PCR and inverse PCR from the chromosomal DNA of Paenibacillus sp. 0602. The open reading frame of pelN encodes a 30 amino acid signal peptide and a 445 amino acid mature protein belonging to the polysaccharide lyase family 1. The maximum Pel activity produced by E. coli in shake flasks reached 2,467.4 U mL−1, and the purified recombinant enzyme exhibits a specific activity of 2,060 U mg−1 on polygalacturonic acid (PGA). The maximum activity was observed in a buffer with 5 mM Ca2+ at pH 9.8 and 65°C. PelN displays a half-life of around 9 h and 42 h at 50°C and 45°C, respectively. The biochemical treatment achieved the maximal reduction of percentage weight (30.5%) of the ramie bast fiber. Conclusions This work represents the first study that describes the extracellular expression of a Pel gene from Paenibacillus species in E. coli. The high yield of the extracellular overexpression, relevant thermostability and efficient degumming using combined treatments indicate its strong potential for large-scale industrial production. PMID:24612647

Instructional Effectiveness of a Computer-Supported Program for Teaching Reading Comprehension Strategies

ERIC Educational Resources Information Center

Ponce, Hector R.; Lopez, Mario J.; Mayer, Richard E.

2012-01-01

This article examines the effectiveness of a computer-based instructional program (e-PELS) aimed at direct instruction in a collection of reading comprehension strategies. In e-PELS, students learn to highlight and outline expository passages based on various types of text structures (such as comparison or cause-and-effect) as well as to…

Nucleotide sequence and expression of a novel pectate lyase gene (pel-3) and a closely linked endopolygalacturonase gene (peh-1) of Erwinia carotovora subsp. carotovora 71.

PubMed Central

Liu, Y; Chatterjee, A; Chatterjee, A K

1994-01-01

Our previous genetic analysis (J. W. Willis, J. K. Engwall, and A. K. Chatterjee, Phytopathology 77:1199-1205, 1987) had revealed a tight linkage between pel-3 (pel, pectate lyase gene) and peh-1 (peh, polygalacturonase gene) within the chromosome of Erwinia carotovora subsp. carotovora 71. Nucleotide sequencing, transcript assays, and expression of enzymatic activities in Escherichia coli have now confirmed that a 3,500-bp segment contains the open reading frames (ORFs) for Pel-3 and Peh-1. The 1,041-bp pel-3 ORF and the 1,206-bp peh-1 ORF are separated by a 579-bp sequence. The genes are transcribed divergently from their own promoters. In E. coli and E. carotovora subsp. carotovora 71, peh-1 is better expressed than pel-3. However, plant signals activate the expression of both the genes in E. carotovora subsp. carotovora. A consensus integration host factor (IHF)-binding sequence upstream of pel-3 appears physiologically significant, since pel-3 promoter activity is higher in an E. coli IHF+ strain than in an IHF- strain. While peh-1 has extensive homology with plant and bacterial peh genes, pel-3 appears not to have significant homology with the pel genes belonging to the pelBC, pelADE, or periplasmic pel families. Pel-3 also is unusual in that it is predicted to contain an ATP- and GTP-binding site motif A (P-loop) not found in the other Pels. Images PMID:8074530

Effect of lipase immobilization on resolution of (R, S)-2-octanol in nonaqueous media using modified ultrastable-Y molecular sieve as support.

PubMed

Dai, Dazhang; Xia, Liming

2006-07-01

The lipase from Penicillium expansum PED-03 (PEL) was immobilized onto modified ultrastable-Y (USY) molecular sieve and the resolution of (R, S)- 2-octanol was carried out in a bioreactor in nonaqueous media by the immobilized lipase. It was found that the conversion rate, enantiomeric excess (ee) value, and enantioselectivity (E) value of the resolution catalyzed by PEL immobilized on modified USY molecular sieve were much higher than those of the reaction catalyzed by free PEL and PEL immobilized on other supports. Immobilized on modified USY molecular sieve, the PEL exhibited obvious activity within a wider pH range and at a much higher temperature and showed a markedly enhanced stability against thermal inactivation, by which the suitable pH of the buffer used for immobilization could be "memorized." The conversion rate of the reaction catalyzed by PEL immobilized on modified USY molecular sieve reached 48.84%, with excellent enantioselectivity (average E value of eight batches >460) in nonaqueous media at "memorial" pH 9.5, 50 degrees C for 24 h, demonstrating a good application potential in the production of optically pure (R, S)-2-octanol.

Comparison of occupational noise legislation in the Americas: an overview and analysis.

PubMed

Arenas, Jorge P; Suter, Alice H

2014-01-01

The workplace contributes significantly to the total dose of daily noise to which a person is subjected. Therefore, millions of people around the world are exposed to potentially dangerous noise levels and consequently, there is an urgent, global need for legislation to adequately protect the auditory health of workers. Occupational noise legislation has been adopted in many of the countries with different degrees of comprehensiveness and varying levels of sophistication. This paper presents a global view of current legislation on occupational noise in the 22 countries that make up the Americas, that is, Latin America, Canada, and the United States. Upon analysis of the legislation, there are notable differences among countries in the defined values for permissible exposure limit (PEL) and exchange rate. Of the countries that have regulations, the majority (81%) use a PEL of 85 dBA. A PEL of 85 dBA and the 3-dB exchange rate are currently used by 32% of the nations in the Americas. Most nations limit impulsive noise exposure to a peak unweighted sound pressure level of 140 dB (or dBC), while a few use slightly lower limits. However, 27% of the countries in the region still have not established regulations with respect to permissible noise levels and exchange rates. This fact is leaving millions of workers in the Americas unprotected against occupational noise. Provide an overview and analysis of the current legislation on occupational noise in the 22 countries that make up the Americas. The information on legislation, regulations, and standards discussed in this paper were obtained directly from official government sources in each country, the International Labour Organization database, or through various colleagues in each country. (1) There are notable differences among countries in the defined values for PEL and exchange rate. (2) Of the countries that have regulations, the majority (81%) use a PEL of 85 dBA. A PEL of 85 dBA and the 3-dB exchange rate are currently used by 32% of the nations in the Americas. (3) Most nations limit impulsive noise exposure to a peak unweighted sound pressure level of 140 dB (or dBC), while a few use slightly lower limits. (4) 27% of the countries in the region still have not established regulations with respect to permissible noise levels and exchange rates. (5) Millions of workers in the Americas are unprotected against occupational noise.

Epigallocatechin-3-Gallate Suppresses Human Herpesvirus 8 Replication and Induces ROS Leading to Apoptosis and Autophagy in Primary Effusion Lymphoma Cells

PubMed Central

Tsai, Ching-Yi; Chen, Chang-Yu; Chiou, Yee-Hsuan; Shyu, Huey-Wen; Lin, Kuan-Hua; Chou, Miao-Chen; Huang, Mei-Han; Wang, Yi-Fen

2017-01-01

Epigallocatechin-3-gallate (EGCG), the major constituent of green tea, has been shown to induce cell death in cancer cells. Primary effusion lymphoma (PEL) is an aggressive neoplasm caused by human herpesvirus 8 (HHV8). In this study, we examined the role of EGCG on PEL cells in cell death and HHV8 replication. We performed trypan blue exclusion assay to assess the cell viability of PEL cells, flow cytometry analysis to examine the cell cycle distribution and reactive oxygen species (ROS) generation, caspase-3 activity to assay apoptosis, acridine orange staining to determine autophagy, and immunoblotting to detect the protein levels involved in apoptosis and autophagy as well as mitogen activated protein kinases (MAPKs) activation upon EGCG treatment. The expression of the HHV8 lytic gene was determined by luciferase reporter assay and reverse transcription-PCR, and viral progeny production was determined by PCR. Results revealed that EGCG induced cell death and ROS generation in PEL cells in a dose-dependent manner. N-acetylcysteine (NAC) inhibited the EGCG-induced ROS and rescued the cell from EGCG-induced cell death. Even though EGCG induced ROS generation in PEL cells, it reduced the production of progeny virus from PEL cells without causing HHV8 reactivation. These results suggest that EGCG may represent a novel strategy for the treatment of HHV8 infection and HHV8-associated lymphomas. PMID:29267216

Sublethal effects in Perinereis gualpensis (Polychaeta: Nereididae) exposed to mercury-pyrene sediment mixture observed in a multipolluted estuary.

PubMed

Díaz-Jaramillo, M; Miglioranza, K S B; Carriquiriborde, P; Marino, D; Pegoraro, C N; Valenzuela, G; Barra, R

2017-08-01

Sediment-living organisms can be subjected to a multi-pollution condition due to an increase in the diversity of contaminants. Sediment mixtures of Mercury (Hg) and some polycyclic aromatics hydrocarbons like Pyrene (Pyr) are common in heavily industrialized coastal zones. In the present study, greater than (>) and less than (<) probable effect concentration levels (PELs) of Hg and Pyr were assessed using spiked sediments in order to determine combined (Hg + Pyr) effects in uptake, metabolization and oxidative balance in the polychaete Perinereis gualpensis at short and medium-term exposure. Hg + Pyr significantly influenced the uptake/kinetics of Hg and Pyr metabolite 1-OH-pyrene in polychaete tissues during the exposure time compared with separate treatments of each analyte (p < 0.05). Both the Hg-only and Pyr-only exposures significantly influenced both enzymatic and non-enzymatic responses respect to control groups (p < 0.05). The Hg-only treatment showed the worst scenario related to the activation and subsequent inhibition of glutathione S- transferase (GST) and peroxidase (GPx) activities, high levels of Thiol-groups (SH-groups), low antioxidant capacity (ACAP) and enhanced lipid peroxidation (TBARS) in the last days of exposure (p < 0.05). In contrast, ragworms exposed to Hg + Pyr showed a significant increase in both enzymatic and non-enzymatic activity during the first days of exposure and the absence of lipid peroxidation during the whole experiment. Our results suggest different oxidative stress scenarios in P. gualpensis when exposed to >PEL Hg concentration with

Pel is a cationic exopolysaccharide that cross-links extracellular DNA in the Pseudomonas aeruginosa biofilm matrix.

PubMed

Jennings, Laura K; Storek, Kelly M; Ledvina, Hannah E; Coulon, Charlène; Marmont, Lindsey S; Sadovskaya, Irina; Secor, Patrick R; Tseng, Boo Shan; Scian, Michele; Filloux, Alain; Wozniak, Daniel J; Howell, P Lynne; Parsek, Matthew R

2015-09-08

Biofilm formation is a complex, ordered process. In the opportunistic pathogen Pseudomonas aeruginosa, Psl and Pel exopolysaccharides and extracellular DNA (eDNA) serve as structural components of the biofilm matrix. Despite intensive study, Pel's chemical structure and spatial localization within mature biofilms remain unknown. Using specialized carbohydrate chemical analyses, we unexpectedly found that Pel is a positively charged exopolysaccharide composed of partially acetylated 1→4 glycosidic linkages of N-acetylgalactosamine and N-acetylglucosamine. Guided by the knowledge of Pel's sugar composition, we developed a tool for the direct visualization of Pel in biofilms by combining Pel-specific Wisteria floribunda lectin staining with confocal microscopy. The results indicate that Pel cross-links eDNA in the biofilm stalk via ionic interactions. Our data demonstrate that the cationic charge of Pel is distinct from that of other known P. aeruginosa exopolysaccharides and is instrumental in its ability to interact with other key biofilm matrix components.

Shelter-In-Pace: Indoor Exposure Assessment During an Airborne Chemical, Biological, Radiological, and Nuclear (CBRN) Event

DTIC Science & Technology

2009-03-01

workers 18 may be repeatedly exposed, day after day, over a working lifetime, without adverse health effects for the conventional 8-hour workday...preventive measures to reduce or eliminate adverse health effects and accidental injuries. [33] NIOSH is the federal agency responsible for conducting...Permissible Exposure Limits (PELs) to protect workers against the health effects of exposure to hazardous substances. PELs are regulatory limits on

Fractionation and potential toxic risk of metals from superficial sediment in Itaipu Lake--boundary between Brazil and Paraguay.

PubMed

Kalwa, Miguel; Quináia, Sueli Pércio; Pletsch, Adelmo L; Techy, Laura; Felsner, Maria Lurdes

2013-01-01

The objective of this study was to evaluate fractions of metals (labile and pseudo-total) extracted from sediment samples collected in Itaipu Lake (boundary between Brazil and Paraguay) and to assess the dynamics and mobility of these fractions by identifying the same bioavailability and ecological risk to metals in the aquatic environment. The concentrations of metal ions were determined by flame atomic absorption spectrometry. There was a correlation between the metal ions, both in the labile and the pseudo-total, with regard to particle size. To assess metals concentrations in sediment, numerical sediment-quality guidelines were applied. The concentrations of aluminum, cadmium, iron, manganese, lead, and zinc in all sediment samples are lower than the proposed probable effects level (PEL), thus possibly indicating that there are no harmful effects from these metals. In contrast, concentrations of copper, chromium, and nickel exceeded the PEL in some samples, thus indicating that these stations are at potential risk. The level of contamination in sediments of Itaipu Lake for all metals was evaluated using contamination factor, degree of contamination, and sum-of-metals toxic unit.

Environmentally friendly cellulose-based polyelectrolytes in wastewater treatment.

PubMed

Grenda, Kinga; Arnold, Julien; Gamelas, José A F; Rasteiro, Maria G

2017-09-01

Natural-based polyelectrolytes (PELs), with all the advantages coming from being produced from renewable and biodegradable sources, are a potential solution for the removal of dyes from wastewater. In this work, surplus Eucalyptus bleached cellulose fibres from a paper mill were modified to increase the charge and solubility of cellulose. First, reactive aldehyde groups were introduced in the cellulose backbone by periodate oxidation of cellulose. Further modification with alkylammonium produced positively charged cellulose-based PELs. The final products were characterized by several analytical techniques. The PEL with the highest substitution degree of cationic groups was evaluated for its performance in decolouration processes, bentonite being used as aid. This was found to be effective for colour removal of either anionic or cationic dyes. Bio-PELs can thus be considered as very favourable eco-friendly flocculation agents for decolouration of harsh effluents from several industries, considering their biodegradable nature and thus the ability to produce less sludge.

Quorum-sensing regulation of the biofilm matrix genes (pel) of Pseudomonas aeruginosa.

PubMed

Sakuragi, Yumiko; Kolter, Roberto

2007-07-01

Quorum sensing (QS) has been previously shown to play an important role in the development of Pseudomonas aeruginosa biofilms (D. G. Davies et al., Science 280:295-298, 1998). Although QS regulation of swarming and DNA release has been shown to play important roles in biofilm development, regulation of genes directly involved in biosynthesis of biofilm matrix has not been described. Here, transcription of the pel operon, essential for the production of a glucose-rich matrix exopolysaccharide, is shown to be greatly reduced in lasI and rhlI mutants. Chemical complementation of the lasI mutant with 3-oxo-dodecanoyl homoserine lactone restores pel transcription to the wild-type level and biofilm formation ability. These findings thus connect QS signaling and transcription of genes responsible for biofilm matrix biosynthesis.

Evaluation of Employer, Teacher, and Student Perceptions of CO-OP/PEL. Final Report.

ERIC Educational Resources Information Center

Hogue, Ken; And Others

A study compared the effectiveness of on-the-job work experience (CO-OP) with pre-employment laboratory experience (PEL) of the six instructional areas in vocational education. This was accomplished by obtaining the perceptions of program completers (1983 graduates), participating employers, and vocational education teachers from seven sample…

Identification of Pectin Degrading Enzymes Secreted by Xanthomonas oryzae pv. oryzae and Determination of Their Role in Virulence on Rice.

PubMed

Tayi, Lavanya; Maku, Roshan V; Patel, Hitendra Kumar; Sonti, Ramesh V

2016-01-01

Xanthomonas oryzae pv.oryzae (Xoo) causes the serious bacterial blight disease of rice. Xoo secretes a repertoire of plant cell wall degrading enzymes (CWDEs) like cellulases, xylanases, esterases etc., which act on various components of the rice cell wall. The major cellulases and xylanases secreted by Xoo have been identified and their role in virulence has been determined. In this study, we have identified some of the pectin degrading enzymes of Xoo and assessed their role in virulence. Bioinformatics analysis indicated the presence of four pectin homogalacturonan (HG) degrading genes in the genome of Xoo. The four HG degrading genes include one polygalacturonase (pglA), one pectin methyl esterase (pmt) and two pectate lyases (pel and pelL). There was no difference in the expression of pglA, pmt and pel genes by laboratory wild type Xoo strain (BXO43) grown in either nutrient rich PS medium or in plant mimic XOM2 medium whereas the expression of pelL gene was induced in XOM2 medium as indicated by qRT-PCR experiments. Gene disruption mutations were generated in each of these four genes. The polygalacturonase mutant pglA- was completely deficient in degrading the substrate Na-polygalacturonicacid (PGA). Strains carrying mutations in the pmt, pel and pelL genes were as efficient as wild type Xoo (BXO43) in cleaving PGA. These observations clearly indicate that PglA is the major pectin degrading enzyme produced by Xoo. The pectin methyl esterase, Pmt, is the pectin de-esterifying enzyme secreted by Xoo as evident from the enzymatic activity assay performed using pectin as the substrate. Mutations in the pglA, pmt, pel and pelL genes have minimal effects on virulence. This suggests that, as compared to cellulases and xylanases, the HG degrading enzymes may not have a major role in the pathogenicity of Xoo.

Identification of Pectin Degrading Enzymes Secreted by Xanthomonas oryzae pv. oryzae and Determination of Their Role in Virulence on Rice

PubMed Central

Tayi, Lavanya; Maku, Roshan V.; Patel, Hitendra Kumar; Sonti, Ramesh V.

2016-01-01

Xanthomonas oryzae pv.oryzae (Xoo) causes the serious bacterial blight disease of rice. Xoo secretes a repertoire of plant cell wall degrading enzymes (CWDEs) like cellulases, xylanases, esterases etc., which act on various components of the rice cell wall. The major cellulases and xylanases secreted by Xoo have been identified and their role in virulence has been determined. In this study, we have identified some of the pectin degrading enzymes of Xoo and assessed their role in virulence. Bioinformatics analysis indicated the presence of four pectin homogalacturonan (HG) degrading genes in the genome of Xoo. The four HG degrading genes include one polygalacturonase (pglA), one pectin methyl esterase (pmt) and two pectate lyases (pel and pelL). There was no difference in the expression of pglA, pmt and pel genes by laboratory wild type Xoo strain (BXO43) grown in either nutrient rich PS medium or in plant mimic XOM2 medium whereas the expression of pelL gene was induced in XOM2 medium as indicated by qRT-PCR experiments. Gene disruption mutations were generated in each of these four genes. The polygalacturonase mutant pglA- was completely deficient in degrading the substrate Na-polygalacturonicacid (PGA). Strains carrying mutations in the pmt, pel and pelL genes were as efficient as wild type Xoo (BXO43) in cleaving PGA. These observations clearly indicate that PglA is the major pectin degrading enzyme produced by Xoo. The pectin methyl esterase, Pmt, is the pectin de-esterifying enzyme secreted by Xoo as evident from the enzymatic activity assay performed using pectin as the substrate. Mutations in the pglA, pmt, pel and pelL genes have minimal effects on virulence. This suggests that, as compared to cellulases and xylanases, the HG degrading enzymes may not have a major role in the pathogenicity of Xoo. PMID:27907079

Effects of anthocyanins on the AhR-CYP1A1 signaling pathway in human hepatocytes and human cancer cell lines

PubMed Central

Kamenickova, Alzbeta; Anzenbacherova, Eva; Pavek, Petr; Soshilov, Anatoly A.; Denison, Michael S.; Zapletalova, Michaela; Anzenbacher, Pavel; Dvorak, Zdenek

2013-01-01

Anthocyanins are plant pigments occurring in flowers and berry fruits. Since a phenomenon of food-drug interactions is increasingly emerging, we examined the effects of 21 major anthocyanins and the extracts from 3 food supplements containing anthocyanins on the aryl hydrocarbon receptor (AhR) – cytochrome P450 CYP1A1 signaling pathway in human hepatocytes and human hepatic HepG2 and intestinal LS174T cancer cells. Pelargonidin-3-O-rutinoside (PEL-2) and cyanidin-3,5-O-diglucoside (CYA-3) dose-dependently activated AhR, as revealed by gene reporter assay. PEL-2 and CYA-3 induced CYP1A1 mRNA but not protein in HepG2 and LS174T cells. Neither compound induced CYP1A1 mRNA and protein in four different primary human hepatocytes cultures. The effects of PEL-2 and CYA-3 on AhR occurred by ligand-dependent and ligand-independent mechanisms, respectively, as demonstrated by ligand binding assay. In a direct enzyme inhibition assay, none of the antocyanins tested inhibited the CYP1A1 marker activity to less than 50% even at 100 µM concentration. PEL-2 and CYA-3 at 100 µM inhibited CYP1A1 to 79% and 65%, respectively. In conclusion, with exception of PEL-2 and CYA-3, there were no effects of 19 major anthocyanins and 3 food supplements containing anthocyanins on AhR-CYP1A1 signaling, implying zero potential of these compounds for food-drug interactions with respect to AhR-CYP1A1 pathway. PMID:23735880

Theoretical modeling of electroosmotic flow in soft microchannels: A variational approach applied to the rectangular geometry

NASA Astrophysics Data System (ADS)

Sadeghi, Arman

2018-03-01

Modeling of fluid flow in polyelectrolyte layer (PEL)-grafted microchannels is challenging due to their two-layer nature. Hence, the pertinent studies are limited only to circular and slit geometries for which matching the solutions for inside and outside the PEL is simple. In this paper, a simple variational-based approach is presented for the modeling of fully developed electroosmotic flow in PEL-grafted microchannels by which the whole fluidic area is considered as a single porous medium of variable properties. The model is capable of being applied to microchannels of a complex cross-sectional area. As an application of the method, it is applied to a rectangular microchannel of uniform PEL properties. It is shown that modeling a rectangular channel as a slit may lead to considerable overestimation of the mean velocity especially when both the PEL and electric double layer (EDL) are thick. It is also demonstrated that the mean velocity is an increasing function of the fixed charge density and PEL thickness and a decreasing function of the EDL thickness and PEL friction coefficient. The influence of the PEL thickness on the mean velocity, however, vanishes when both the PEL thickness and friction coefficient are sufficiently high.

Immunophenotypic analysis of the Kaposi sarcoma herpesvirus (KSHV; HHV-8)-infected B cells in HIV+ multicentric Castleman disease (MCD).

PubMed

Chadburn, A; Hyjek, E M; Tam, W; Liu, Y; Rengifo, T; Cesarman, E; Knowles, D M

2008-11-01

Kaposi sarcoma herpesvirus (KSHV) is aetiologically related to Kaposi sarcoma, classical and extracavitary primary effusion lymphoma (PEL; EC-PEL) and multicentric Castleman disease (MCD), entities preferentially occurring in HIV-infected individuals. Characterization of HIV-associated PELs/EC-PELs suggests that the KSHV-infected malignant cells originate from a pre-terminal stage of B-cell differentiation. However, only limited phenotypic studies have been performed on HIV+ MCD, including for PR domain containing 1 with zinc finger domain/B lymphocyte-induced maturation protein 1 (PRDM1/BLIMP1), a key regulator of terminal B-cell differentiation. The aim was to characterize KSHV-infected cells in 17 cases of HIV+ MCD. Double immunohistochemistry and immunohistochemistry-in situ hybridization were used to characterize the KSHV-infected cells in MCD; the results were compared with the phenotypic profiles of 39 PELs/EC-PELs and seven PEL cell lines. Whereas the immunophenotype of KSHV-infected cells in MCD and malignant KSHV+ PEL cells was similar (PAX5, Bcl-6-; PRDM1/BLIMP1, IRF4/MUM1+; Ki67+), the MCD KSHV-infected cells differed, as they expressed OCT2, cytoplasmic lambda immunoglobulin; variably expressed CD27; lacked CD138; and were Epstein-Barr virus negative. Although both PEL and MCD originate from KSHV-infected pre-terminally differentiated B cells, these findings, with previously reported genetic studies, indicate HIV+ MCD may arise from extrafollicular B cells, whereas PELs may originate from cells that have traversed the germinal centre.

A preliminary evaluation of sediment quality assessment values for freshwater ecosystems

USGS Publications Warehouse

Smith, Sherri L.; MacDonald, Donald D.; Keenleyside, Karen A.; Ingersoll, Christopher G.; Field, L. Jay

1996-01-01

Sediment quality assessment values were developed using a weight of evidence approach in which matching biological and chemical data from numerous modelling, laboratory, and field studies performed on freshwater sediments were compiled and analyzed. Two assessment values (a threshold effect level (TEL) and a probable effect level(PEL)) were derived for 23 substances, including eight trace metals, six individual polycyclic aromatic hydrocarbons (PAHs), total polychlorinated biphenyls (PCBs), and eight pesticides. The two values defined three ranges of chemical concentrations; those that were (1) rarely, (2) occasionally, and (3) frequently associated with adverse biological effects. An evaluation of the percent incidence of adverse biological effects within the three concentration ranges indicated that the reliability of the TELs (i.e., the degree to which the TELs represent concentrations within the data set below which adverse effects rarely occur) was consistently good. However, this preliminary evaluation indicated that most of the PELs were less reliable (i.e., they did not adequately represent concentrations within the data set above which adverse effects frequently occur). Nonetheless, these values were often comparable to other biological effects-based assessment values (which were themselves reliable), which increased the level of confidence that could be placed in our values. This method is being used as a basis for developing national sediment quality guidelines for freshwater systems in Canada and sediment effect concentrations as part of the Assessment and Remediation of Contaminated Sediments (ARCS) program in the Great Lakes.

Comparative pharmacokinetic profiles of selected irreversible tyrosine kinase inhibitors, neratinib and pelitinib, with apigenin in rat plasma by UPLC-MS/MS.

PubMed

Maher, Hadir M; Alzoman, Nourah Z; Shehata, Shereen M; Abahussain, Ashwag O

2017-04-15

Neratinib (NER) and pelitinib (PEL) are irreversible tyrosine kinase inhibitors (TKIs) that have been recently employed in cancer treatment. Apigenin (API), among other flavonoids, is known to have antioxidant, anti-proliferative, and carcinogenic effect. API can potentiate the antitumor effect of chemotherapeutic agents and/or alleviate the side effects of many anticancer agents. Since TKIs are mostly metabolized by CYP3A4 enzymes and that API could alter the enzymatic activity, potential drug interactions could be expected following their co-aministration. In the present study, a bioanalytical UPLC-MS/MS method has been developed and validated for the quantification of NER and PEL in rat plasma, using domperidone (DOM) as an internal standard. Sample preparation was carried out using solid phase extraction (SPE) with C18 cartridges with good extraction recovery of not less than 92.42% (NER) and 89.73% (PEL). Chromatographic analysis was performed on a Waters BEH C18 column with a mobile phase composed of acetonitrile and water, (70:30, v/v), each with 0.1% formic acid. Quantitation was performed using multiple reaction monitoring (MRM) of the transitions from protonated precursor ions [M+H] + , at m/z 557.30 (NER), m/z 468.21 (PEL), and at m/z 426.27 (DOM), to selected product ions at m/z 112.05 (NER), m/z 395.22 (PEL), and at m/z 175.18 (DOM). The method was fully validated as per the FDA guidelines over the concentration range of 0.5-200ng/mL with very low lower limit of quantification (LLOQ) of 0.5ng/mL for both NER and PEL. The intra- and inter-day assay precision and accuracy were evaluated for both drugs and the calculated values of percentage relative standards deviations (%RSD) and relative errors (%E r ) were within the acceptable limits (<15%) for concentrations other than LLOQ and 20% for LLOQ. The applicability of the method was extended to study the possibility of drug interactions following the oral co-administration of NER/PEL with API. Thus, this study could be readily applied in therapeutic drug monitoring (TDM) of cancerous patients receiving such drug combinations. Copyright © 2017 Elsevier B.V. All rights reserved.

Extracellular secretion of pectate lyase by the Erwinia chrysanthemi out pathway is dependent upon Sec-mediated export across the inner membrane.

PubMed Central

He, S Y; Schoedel, C; Chatterjee, A K; Collmer, A

1991-01-01

The plant pathogenic enterobacterium Erwinia chrysanthemi EC16 secretes several extracellular, plant cell wall-degrading enzymes, including pectate lyase isozyme PelE. Secretion kinetics of 35S-labeled PelE indicated that the precursor of PelE was rapidly processed by the removal of the amino-terminal signal peptide and that the resulting mature PelE remained cell bound for less than 60 s before being secreted to the bacterial medium. PelE-PhoA (alkaline phosphatase) hybrid proteins generated in vivo by TnphoA insertions were mostly localized in the periplasm of E. chrysanthemi, and one hybrid protein was observed to be associated with the outer membrane of E. chrysanthemi in an out gene-dependent manner. A gene fusion resulting in the substitution of the beta-lactamase signal peptide for the first six amino acids of the PelE signal peptide did not prevent processing or secretion of PelE in E. chrysanthemi. When pelE was overexpressed, mature PelE protein accumulated in the periplasm rather than the cytoplasm in cells of E. chrysanthemi and Escherichia coli MC4100 (pCPP2006), which harbors a functional cluster of E. chrysanthemi out genes. Removal of the signal peptide from pre-PelE was SecA dependent in E. coli MM52 even in the presence of the out gene cluster. These data indicate that the extracellular secretion of pectic enzymes by E. chrysanthemi is an extension of the Sec-dependent pathway for general export of proteins across the bacterial inner membrane. Images PMID:1829728

Encouraging Education in an Urban School District: Evidence from the Philadelphia Educational Longitudinal Study

ERIC Educational Resources Information Center

Furstenberg, Frank F., Jr.; Neumark, David

2007-01-01

We study a set of programs implemented in Philadelphia high schools that focus on boosting high school graduation, and especially college attendance, using data from the Philadelphia Educational Longitudinal Study (PELS). We examine the effects of these programs on a set of schooling-related outcomes during and after high school. The PELS data-set…

Pel is a cationic exopolysaccharide that cross-links extracellular DNA in the Pseudomonas aeruginosa biofilm matrix

PubMed Central

Jennings, Laura K.; Storek, Kelly M.; Ledvina, Hannah E.; Coulon, Charlène; Marmont, Lindsey S.; Sadovskaya, Irina; Secor, Patrick R.; Tseng, Boo Shan; Scian, Michele; Filloux, Alain; Wozniak, Daniel J.; Howell, P. Lynne; Parsek, Matthew R.

2015-01-01

Biofilm formation is a complex, ordered process. In the opportunistic pathogen Pseudomonas aeruginosa, Psl and Pel exopolysaccharides and extracellular DNA (eDNA) serve as structural components of the biofilm matrix. Despite intensive study, Pel’s chemical structure and spatial localization within mature biofilms remain unknown. Using specialized carbohydrate chemical analyses, we unexpectedly found that Pel is a positively charged exopolysaccharide composed of partially acetylated 1→4 glycosidic linkages of N-acetylgalactosamine and N-acetylglucosamine. Guided by the knowledge of Pel’s sugar composition, we developed a tool for the direct visualization of Pel in biofilms by combining Pel-specific Wisteria floribunda lectin staining with confocal microscopy. The results indicate that Pel cross-links eDNA in the biofilm stalk via ionic interactions. Our data demonstrate that the cationic charge of Pel is distinct from that of other known P. aeruginosa exopolysaccharides and is instrumental in its ability to interact with other key biofilm matrix components. PMID:26311845

Engineering controls for furniture strippers to meet the OSHA methylene chloride PEL.

PubMed

Estill, Cheryl Fairfield; Watkins, Daniel S; Shulman, Stanley A; Kurimo, Robert W; Kovein, Ronald J

2002-01-01

This case study demonstrates how methylene chloride exposures during furniture stripping can be reduced to below the Occupational Safety and Health Administration (OSHA) permissible exposure limit (PEL) of 25 ppm (as an 8-hour time-weighted average). Five surveys were conducted at one facility; the first four resulted in employee exposure geometric means from 39 to 332 ppm. For the fifth survey local exhaust ventilation was used at the stripping tank and the rinsing area, which together exhausted 138 m3/min (4860 ft3/min). Additional controls included providing adequate make-up air, adding paraffin wax to the stripping solution, raising the level of the stripping solution in the tank, and discussing good work practices with the employee. The employees' methylene chloride exposures during the fifth survey resulted in a geometric mean of 5.6 ppm with a 95% upper confidence limit of 8.3 ppm, which was found to be significantly lower than the OSHA PEL and the OSHA action level of 12.5 ppm. The cost of the ventilation system was $8900.

Expression and Bioinformatics Analysis of Pectate Lyase Gene from Bacillus subtilis521

NASA Astrophysics Data System (ADS)

Xiao, Jing; Lu, Fu-Ping; Li, Yu; Li, Jin-Ting

In order to exploit new genetic resources, Pectate lyase(PEL) gene was amplified by PCR using the genome DNA from an alkaline Bacillus subtilis521. The PCR product was inserted into pET22b(+) vector. The recombinant plasmids were cloned in E.coli DH5α and then expressed in E.coli BL21. When cultured in the optimized medium, the positive clones E.coli BL21(pET22b(+)pel)showed intracellular pectate lyase activity of 90.0 U/mL. It was indicated that we had obtained the correct PEL gene. The pel has an open reading frame of 1263 nucleotides and codes for a product of 420 amino acids with a calculated molecular mass of 45.5 kD. Based on computer assisted analysis, a signal peptides and two conserved domains were revealed. The sequence analysis for PEL showed that it shares 26-82% homology with other strains in GenBank. In addition, the advanced structure of PEL were also predicted and analysed. This study will help to the experimental design of PEL fermentation and production purification and enzyme evolution.

Continuing exposure to hexavalent chromium, a known lung carcinogen: an analysis of OSHA compliance inspections, 1990-2000.

PubMed

Lurie, Peter; Wolfe, Sidney M

2002-11-01

Hexavalent chromium is widely recognized to be a lung carcinogen. However, the U.S. Occupational Safety and Health Administration (OSHA) has failed to reduce the permissible exposure limit (PEL), despite having acknowledged in 1994 that the current limit is too high. In 1993, Public Citizen and the Paper, Allied-Industrial, Chemical and Energy Workers International Union (PACE) petitioned to lower the PEL from the current 100 microg/m(3) to 0.5 microg/m(3) as an 8-hr time-weighted average (TWA). To assess industry compliance with the current PEL, and to determine the feasibility of achieving the proposed lower limit of 0.5 microg/m(3), we conducted a secondary data analysis of OSHA's Integrated Management Information System (IMIS) database. This database contains 813 measurements of hexavalent chromium exposure from inspections performed during the years 1990-2000. There was a statistically significant decline in the annual number of measurements over the study period from 127 in 1990 to 67 in 2000 (F = 0.0009; linear regression). The median TWA measurement was 10 microg/m(3) (range: 0.01-13,960 microg/m(3)) and the median ceiling measurement was 40.5 microg/m(3) (range: 0.25-25,000 microg/m(3)). Neither median TWA nor median ceiling exposures (if hexavalent chromium was detected) declined significantly during the study period (F = 0.065 and 0.57, respectively). Overall, 13.7% of TWA measurements were at or below the Public Citizen/PACE proposed standard; 65.0% were between the Public Citizen/PACE proposal and the current OSHA PEL; and 21.3% exceeded the OSHA PEL. Compared to OSHA measurements, state measurements were less likely to detect hexavalent chromium (40.2% vs. 52.1%; P = 0.0007; chi-square) and less likely to issue any citation (9.3% vs. 19.1%; P = 0.0003), including citations for overexposure if the exposure exceeded the PEL (54.8% vs. 78.8%; P = 0.012). U.S. workers continue to be exposed to dangerously high hexavalent chromium levels, but low exposure levels were found in some industries. Further investigations should examine whether state plans provide weaker enforcement than federal OSHA. Copyright 2002 Wiley-Liss, Inc.

Statistical Modeling of Occupational Exposure to Polycyclic Aromatic Hydrocarbons Using OSHA Data.

PubMed

Lee, Derrick G; Lavoué, Jérôme; Spinelli, John J; Burstyn, Igor

2015-01-01

Polycyclic aromatic hydrocarbons (PAHs) are a group of pollutants with multiple variants classified as carcinogenic. The Occupational Safety and Health Administration (OSHA) provided access to two PAH exposure databanks of United States workplace compliance testing data collected between 1979 and 2010. Mixed-effects logistic models were used to predict the exceedance fraction (EF), i.e., the probability of exceeding OSHA's Permissible Exposure Limit (PEL = 0.2 mg/m3) for PAHs based on industry and occupation. Measurements of coal tar pitch volatiles were used as a surrogate for PAHs. Time, databank, occupation, and industry were included as fixed-effects while an identifier for the compliance inspection number was included as a random effect. Analyses involved 2,509 full-shift personal measurements. Results showed that the majority of industries had an estimated EF < 0.5, although several industries, including Standardized Industry Classification codes 1623 (Water, Sewer, Pipeline, and Communication and Powerline Construction), 1711 (Plumbing, Heating, and Air-Conditioning), 2824 (Manmade Organic Fibres), 3496 (Misc. Fabricated Wire products), and 5812 (Eating Places), and Major group's 13 (Oil and Gas Extraction) and 30 (Rubber and Miscellaneous Plastic Products), were estimated to have more than an 80% likelihood of exceeding the PEL. There was an inverse temporal trend of exceeding the PEL, with lower risk in most recent years, albeit not statistically significant. Similar results were shown when incorporating occupation, but varied depending on the occupation as the majority of industries predicted at the administrative level, e.g., managers, had an estimated EF < 0.5 while at the minimally skilled/laborer level there was a substantial increase in the estimated EF. These statistical models allow the prediction of PAH exposure risk through individual occupational histories and will be used to create a job-exposure matrix for use in a population-based case-control study exploring PAH exposure and breast cancer risk.

PEL Benefits: Measuring the Benefits of Planning and Environmental Linkages (PEL)

DOT National Transportation Integrated Search

2015-10-01

The Federal Highway Administration (FHWA) commissioned this report to explore and document the benefits stemming from the incorporation of Planning and Environmental Linkage (PEL) strategies into State, regional, and local planning and project develo...

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

Fan, Yue; Iwashita, Takuya; Egami, Takeshi

Complex states in glasses can be neatly expressed by the potential energy landscape (PEL). But, because PEL is highly multi-dimensional it is difficult to describe how the system moves around in PEL. We demonstrate that it is possible to predict the evolution of macroscopic state in a metallic glass, such as ageing and rejuvenation, through a set of simple equations describing excitations in the PEL. The key to this simplification is the realization that the step of activation from the initial state to the saddle point in PEL and the following step of relaxation to the final state are essentiallymore » decoupled. Furthermore, the model shows that the interplay between activation and relaxation in PEL is the key driving force that simultaneously explains both the equilibrium of supercooled liquid and the thermal hysteresis observed in experiments. It further predicts anomalous peaks in truncated thermal scanning, validated by independent molecular dynamics simulation.« less

Combination of Arsenic and Interferon-α Inhibits Expression of KSHV Latent Transcripts and Synergistically Improves Survival of Mice with Primary Effusion Lymphomas

PubMed Central

El Hajj, Hiba; Ali, Jihane; Ghantous, Akram; Hodroj, Dana; Daher, Ahmad; Zibara, Kazem; Journo, Chloé; Otrock, Zaher; Zaatari, Ghazi; Mahieux, Renaud; El Sabban, Marwan; Bazarbachi, Ali; Abou Merhi, Raghida

2013-01-01

Background Kaposi sarcoma-associated herpesvirus (KSHV) is the etiologic agent of primary effusion lymphomas (PEL). PEL cell lines infected with KSHV, but negative for Epstein-Barr virus have a tumorigenic potential in non-obese diabetic/severe combined immunodeficient mice and result in efficient engraftment and formation of malignant ascites with notable abdominal distension, consistent with the clinical manifestations of PEL in humans. Methodology/Principal Findings Using this preclinical mouse model, we demonstrate that the combination of arsenic trioxide and interferon-alpha (IFN) inhibits proliferation, induces apoptosis and downregulates the latent viral transcripts LANA-1, v-FLIP and v-Cyc in PEL cells derived from malignant ascites. Furthermore, this combination decreases the peritoneal volume and synergistically increases survival of PEL mice. Conclusion/Significance These results provide a promising rationale for the therapeutic use of arsenic/IFN in PEL patients. PMID:24250827

Combination of arsenic and interferon-α inhibits expression of KSHV latent transcripts and synergistically improves survival of mice with primary effusion lymphomas.

PubMed

El Hajj, Hiba; Ali, Jihane; Ghantous, Akram; Hodroj, Dana; Daher, Ahmad; Zibara, Kazem; Journo, Chloé; Otrock, Zaher; Zaatari, Ghazi; Mahieux, Renaud; El Sabban, Marwan; Bazarbachi, Ali; Abou Merhi, Raghida

2013-01-01

Kaposi sarcoma-associated herpesvirus (KSHV) is the etiologic agent of primary effusion lymphomas (PEL). PEL cell lines infected with KSHV, but negative for Epstein-Barr virus have a tumorigenic potential in non-obese diabetic/severe combined immunodeficient mice and result in efficient engraftment and formation of malignant ascites with notable abdominal distension, consistent with the clinical manifestations of PEL in humans. Using this preclinical mouse model, we demonstrate that the combination of arsenic trioxide and interferon-alpha (IFN) inhibits proliferation, induces apoptosis and downregulates the latent viral transcripts LANA-1, v-FLIP and v-Cyc in PEL cells derived from malignant ascites. Furthermore, this combination decreases the peritoneal volume and synergistically increases survival of PEL mice. These results provide a promising rationale for the therapeutic use of arsenic/IFN in PEL patients.

Dysregulation of fatty acid synthesis and glycolysis in non-Hodgkin lymphoma

PubMed Central

Bhatt, Aadra P.; Jacobs, Sarah R.; Freemerman, Alex J.; Makowski, Liza; Rathmell, Jeffrey C.; Dittmer, Dirk P.; Damania, Blossom

2012-01-01

The metabolic differences between B-NHL and primary human B cells are poorly understood. Among human B-cell non-Hodgkin lymphomas (B-NHL), primary effusion lymphoma (PEL) is a unique subset that is linked to infection with Kaposi's sarcoma-associated herpesvirus (KSHV). We report that the metabolic profiles of primary B cells are significantly different from that of PEL. Compared with primary B cells, both aerobic glycolysis and fatty acid synthesis (FAS) are up-regulated in PEL and other types of nonviral B-NHL. We found that aerobic glycolysis and FAS occur in a PI3K-dependent manner and appear to be interdependent. PEL overexpress the fatty acid synthesizing enzyme, FASN, and both PEL and other B-NHL were much more sensitive to the FAS inhibitor, C75, than primary B cells. Our findings suggest that FASN may be a unique candidate for molecular targeted therapy against PEL and other B-NHL. PMID:22752304

Development and evaluation of sediment quality guidelines for Florida coastal waters

USGS Publications Warehouse

MacDonald, Donald D.; Carr, R. Scott; Calder, Fred D.; Long, Edward R.; Ingersoll, Christopher G.

1996-01-01

The weight-of-evidence approach to the development of sediment quality guidelines (SQGs) was modified to support the derivation of biological effects-based SQGs for Florida coastal waters. Numerical SQGs were derived for 34 substances, including nine trace metals, 13 individual polycyclic aromatic hydrocarbons (PAHs), three groups of PAHs, total polychlorinated biphenyls (PCBs), seven pesticides and one phthalate ester. For each substance, a threshold effects level (TEL) and a probable effects level (PEL) was calculated. These two values defined three ranges of chemical concentrations, including those that were (1) rarely, (2) occasionally or (3) frequently associated with adverse effects. The SQGs were then evaluated to determine their degree of agreement with other guidelines (an indicator of comparability) and the percent incidence of adverse effects within each concentration range (an indicator of reliability). The guidelines also were used to classify (using a dichotomous system: toxic, with one or more exceedances of the PELs or non-toxic, with no exceedances of the TELs) sediment samples collected from various locations in Florida and the Gulf of Mexico. The accuracy of these predictions was then evaluated using the results of the biological tests that were performed on the same sediment samples. The resultant SQGs were demonstrated to provide practical, reliable and predictive tools for assessing sediment quality in Florida and elsewhere in the southeastern portion of the United States.

External Loops at the C Terminus of Erwinia chrysanthemi Pectate Lyase C Are Required for Species-Specific Secretion through the Out Type II Pathway

PubMed Central

Lindeberg, Magdalen; Boyd, Carol M.; Keen, Noel T.; Collmer, Alan

1998-01-01

The type II secretion system (main terminal branch of the general secretion pathway) is used by diverse gram-negative bacteria to secrete extracellular proteins. Proteins secreted by this pathway are synthesized with an N-terminal signal peptide which is removed upon translocation across the inner membrane, but the signals which target the mature proteins for secretion across the outer membrane are unknown. The plant pathogens Erwinia chrysanthemi and Erwinia carotovora secrete several isozymes of pectate lyase (Pel) by the out-encoded type II pathway. However, these two bacteria cannot secrete Pels encoded by heterologously expressed pel genes from the other species, suggesting the existence of species-specific secretion signals within these proteins. The functional cluster of E. chrysanthemi out genes carried on cosmid pCPP2006 enables Escherichia coli to secrete E. chrysanthemi, but not E. carotovora, Pels. We exploited the high sequence similarity between E. chrysanthemi PelC and E. carotovora Pel1 to construct 15 hybrid proteins in which different regions of PelC were replaced with homologous sequences from Pel1. The differential secretion of these hybrid proteins by E. coli(pCPP2006) revealed M118 to D175 and V215 to C329 as regions required for species-specific secretion of PelC. We propose that the primary targeting signal is contained within the external loops formed by G274 to C329 but is dependent on residues in M118 to D170 and V215 to G274 for proper positioning. PMID:9515910

Catheter-Associated Urinary Tract Infection by Pseudomonas aeruginosa Is Mediated by Exopolysaccharide-Independent Biofilms

PubMed Central

Cole, Stephanie J.; Records, Angela R.; Orr, Mona W.; Linden, Sara B.

2014-01-01

Pseudomonas aeruginosa is an opportunistic human pathogen that is especially adept at forming surface-associated biofilms. P. aeruginosa causes catheter-associated urinary tract infections (CAUTIs) through biofilm formation on the surface of indwelling catheters. P. aeruginosa encodes three extracellular polysaccharides, PEL, PSL, and alginate, and utilizes the PEL and PSL polysaccharides to form biofilms in vitro; however, the requirement of these polysaccharides during in vivo infections is not well understood. Here we show in a murine model of CAUTI that PAO1, a strain harboring pel, psl, and alg genes, and PA14, a strain harboring pel and alg genes, form biofilms on the implanted catheters. To determine the requirement of exopolysaccharide during in vivo biofilm infections, we tested isogenic mutants lacking the pel, psl, and alg operons and showed that PA14 mutants lacking these operons can successfully form biofilms on catheters in the CAUTI model. To determine the host factor(s) that induces the ΔpelD mutant to form biofilm, we tested mouse, human, and artificial urine and show that urine can induce biofilm formation by the PA14 ΔpelD mutant. By testing the major constituents of urine, we show that urea can induce a pel-, psl-, and alg-independent biofilm. These pel-, psl-, and alg-independent biofilms are mediated by the release of extracellular DNA. Treatment of biofilms formed in urea with DNase I reduced the biofilm, indicating that extracellular DNA supports biofilm formation. Our results indicate that the opportunistic pathogen P. aeruginosa utilizes a distinct program to form biofilms that are independent of exopolysaccharides during CAUTI. PMID:24595142

kdgREcc Negatively Regulates Genes for Pectinases, Cellulase, Protease, HarpinEcc, and a Global RNA Regulator in Erwinia carotovora subsp. carotovora†

PubMed Central

Liu, Yang; Jiang, Guoqiao; Cui, Yaya; Mukherjee, Asita; Ma, Wei Lei; Chatterjee, Arun K.

1999-01-01

Erwinia carotovora subsp. carotovora produces extracellular pectate lyase (Pel), polygalacturonase (Peh), cellulase (Cel), and protease (Prt). The concerted actions of these enzymes largely determine the virulence of this plant-pathogenic bacterium. E. carotovora subsp. carotovora also produces HarpinEcc, the elicitor of the hypersensitive reaction. We document here that KdgREcc (Kdg, 2-keto-3-deoxygluconate; KdgR, general repressor of genes involved in pectin and galacturonate catabolism), a homolog of the E. chrysanthemi repressor, KdgREch and the Escherichia coli repressor, KdgREco, negatively controls not only the pectinases, Pel and Peh, but also Cel, Prt, and HarpinEcc production in E. carotovora subsp. carotovora. The levels of pel-1, peh-1, celV, and hrpNEcc transcripts are markedly affected by KdgREcc. The KdgREcc− mutant is more virulent than the KdgREcc+ parent. Thus, our data for the first time establish a global regulatory role for KdgREcc in E. carotovora subsp. carotovora. Another novel observation is the negative effect of KdgREcc on the transcription of rsmB (previously aepH), which specifies an RNA regulator controlling exoenzyme and HarpinEcc production. The levels of rsmB RNA are higher in the KdgREcc− mutant than in the KdgREcc+ parent. Moreover, by DNase I protection assays we determined that purified KdgREcc protected three 25-bp regions within the transcriptional unit of rsmB. Alignment of the protected sequences revealed the 21-mer consensus sequence of the KdgREcc-binding site as 5′-G/AA/TA/TGAAA[N6]TTTCAG/TG/TA-3′. Two such KdgREcc-binding sites occur in rsmB DNA in a close proximity to each other within nucleotides +79 and +139 and the third KdgREcc-binding site within nucleotides +207 and +231. Analysis of lacZ transcriptional fusions shows that the KdgR-binding sites negatively affect the expression of rsmB. KdgREcc also binds the operator DNAs of pel-1 and peh-1 genes and represses expression of a pel1-lacZ and a peh1-lacZ transcriptional fusions. We conclude that KdgREcc affects extracellular enzyme production by two ways: (i) directly, by inhibiting the transcription of exoenzyme genes; and (ii) indirectly, by preventing the production of a global RNA regulator. Our findings support the idea that KdgREcc affects transcription by promoter occlusion, i.e., preventing the initiation of transcription, and by a roadblock mechanism, i.e., by affecting the elongation of transcription. PMID:10198003

Ceramides promote apoptosis for virus-infected lymphoma cells through induction of ceramide synthases and viral lytic gene expression

PubMed Central

Dai, Lu; Trillo-Tinoco, Jimena; Bai, Aiping; Chen, Yihan; Bielawski, Jacek; Del Valle, Luis; Smith, Charles D.; Ochoa, Augusto C.; Qin, Zhiqiang; Parsons, Chris

2015-01-01

Kaposi's sarcoma-associated herpesvirus (KSHV) is the etiologic agent for several human cancers including primary effusion lymphoma (PEL), a rapidly progressive malignancy arising preferentially in immunocompromised patients. With conventional chemotherapy, PEL continues to portend high mortality, dictating the development of novel therapeutic strategies. Sphingosine kinase 2 (SphK2) represents a key gatekeeper for sphingolipid metabolism, responsible for conversion of ceramides to sphingosine-1-phosphate (S1P). We have previously demonstrated that targeting SphK2 using a novel selective inhibitor, ABC294640, leads to intracellular accumulation of ceramides and induces apoptosis for KSHV-infected PEL cells, while suppressing tumor progression in vivo. In the current study, we sought to determine whether specific ceramide/dh-ceramide species and related ceramide synthases (CerS) impact viability for KSHV-infected PEL cells during targeting of SphK2. We found that several specific ceramide and dihydro(dh)-ceramide species and their associated CerS reduce PEL survival and tumor expansion in vitro and in vivo. Moreover, we found that dhC16-Cer induces PEL apoptosis in part through activation of KSHV lytic gene expression. These data further implicate bioactive sphingolipids in regulation of PEL survival, and provide justification for future studies evaluating clinically relevant ceramide analogs or mimetics for their potential as therapeutic agents for PEL. PMID:26327294

Key practices for implementing geospatial technologies for a planning and environment linkages (PEL) approach

DOT National Transportation Integrated Search

2008-07-01

This report presents three case studies that illustrate how geographic information systems (GIS) have been used to implement the Federal Highway Administrations (FHWA) Planning and Environment Linkages (PEL) approach. The PEL approach provides inf...

Cytologic and immunocytochemical features of EBV negative primary effusion lymphoma: report on seven Japanese cases.

PubMed

Kishimoto, Koji; Kitamura, Takashi; Hirayama, Yoshiko; Tate, Genshu; Mitsuya, Toshiyuki

2009-04-01

Primary effusion lymphoma (PEL) is very rare type of non-Hodgkin's lymphoma (NHL) usually confined to the body cavities such as the pleural space, pericardium, and peritoneum. PEL is a human herpes virus-8 (HHV-8)-associated lymphoma and commonly observed in human immunodeficiency virus (HIV)-infected patients. However, HIV-infected patients are extremely fewer in Japan in comparison with those in Western countries; PEL is usually not associated with HIV infection in Japan. This report presents seven Japanese cases of PEL. In situ hybridization revealed that the PEL cells were negative for EBV in all cases. An immunocytological analysis showed that only one case was positive for HHV-8, and PEL cells were positive for CD20 in all cases. MUM1 was positive, but CD10 and CD138 were negative in six cases. One case each was positive for CD30 and BCL-6. The phenotypic patterns of HIV-related is BCL6-/MUM1+/CD138+, thus, the phenotypic findings observed by immunocytochemistry in this study were somehow different from those reported in Western countries. However, the cytomorphological features of PEL cells showed large cell size, abundant basophilic cytoplasm, coarse chromatin, and occasional binucleated or multinucleated cells, similar to a large cell immunoblastic and anaplastic large cell lymphoma, indicating that the cytomorphological characteristics of PE cells in Giemsa and Papanicolaou stain were consistent with those reported abroad. The prognosis for PEL in these cases was poor, but the survival time was variable ranging from 1 month to 54 months, and was different from that of Western cases. No p16/CDKN2A expression was observed, and one case showed PEL cells with a BLIMP1 mutation.

Exopolysaccharide biosynthetic glycoside hydrolases can be utilized to disrupt and prevent Pseudomonas aeruginosa biofilms.

PubMed

Baker, Perrin; Hill, Preston J; Snarr, Brendan D; Alnabelseya, Noor; Pestrak, Matthew J; Lee, Mark J; Jennings, Laura K; Tam, John; Melnyk, Roman A; Parsek, Matthew R; Sheppard, Donald C; Wozniak, Daniel J; Howell, P Lynne

2016-05-01

Bacterial biofilms present a significant medical challenge because they are recalcitrant to current therapeutic regimes. A key component of biofilm formation in the opportunistic human pathogen Pseudomonas aeruginosa is the biosynthesis of the exopolysaccharides Pel and Psl, which are involved in the formation and maintenance of the structural biofilm scaffold and protection against antimicrobials and host defenses. Given that the glycoside hydrolases PelAh and PslGh encoded in the pel and psl biosynthetic operons, respectively, are utilized for in vivo exopolysaccharide processing, we reasoned that these would provide specificity to target P. aeruginosa biofilms. Evaluating these enzymes as potential therapeutics, we demonstrate that these glycoside hydrolases selectively target and degrade the exopolysaccharide component of the biofilm matrix. PelAh and PslGh inhibit biofilm formation over a 24-hour period with a half maximal effective concentration (EC50) of 69.3 ± 1.2 and 4.1 ± 1.1 nM, respectively, and are capable of disrupting preexisting biofilms in 1 hour with EC50 of 35.7 ± 1.1 and 12.9 ± 1.1 nM, respectively. This treatment was effective against clinical and environmental P. aeruginosa isolates and reduced biofilm biomass by 58 to 94%. These noncytotoxic enzymes potentiated antibiotics because the addition of either enzyme to a sublethal concentration of colistin reduced viable bacterial counts by 2.5 orders of magnitude when used either prophylactically or on established 24-hour biofilms. In addition, PelAh was able to increase neutrophil killing by ~50%. This work illustrates the feasibility and benefits of using bacterial exopolysaccharide biosynthetic glycoside hydrolases to develop novel antibiofilm therapeutics.

Exopolysaccharide biosynthetic glycoside hydrolases can be utilized to disrupt and prevent Pseudomonas aeruginosa biofilms

PubMed Central

Baker, Perrin; Hill, Preston J.; Snarr, Brendan D.; Alnabelseya, Noor; Pestrak, Matthew J.; Lee, Mark J.; Jennings, Laura K.; Tam, John; Melnyk, Roman A.; Parsek, Matthew R.; Sheppard, Donald C.; Wozniak, Daniel J.; Howell, P. Lynne

2016-01-01

Bacterial biofilms present a significant medical challenge because they are recalcitrant to current therapeutic regimes. A key component of biofilm formation in the opportunistic human pathogen Pseudomonas aeruginosa is the biosynthesis of the exopolysaccharides Pel and Psl, which are involved in the formation and maintenance of the structural biofilm scaffold and protection against antimicrobials and host defenses. Given that the glycoside hydrolases PelAh and PslGh encoded in the pel and psl biosynthetic operons, respectively, are utilized for in vivo exopolysaccharide processing, we reasoned that these would provide specificity to target P. aeruginosa biofilms. Evaluating these enzymes as potential therapeutics, we demonstrate that these glycoside hydrolases selectively target and degrade the exopolysaccharide component of the biofilm matrix. PelAh and PslGh inhibit biofilm formation over a 24-hour period with a half maximal effective concentration (EC50) of 69.3 ± 1.2 and 4.1 ± 1.1 nM, respectively, and are capable of disrupting preexisting biofilms in 1 hour with EC50 of 35.7 ± 1.1 and 12.9 ± 1.1 nM, respectively. This treatment was effective against clinical and environmental P. aeruginosa isolates and reduced biofilm biomass by 58 to 94%. These noncytotoxic enzymes potentiated antibiotics because the addition of either enzyme to a sublethal concentration of colistin reduced viable bacterial counts by 2.5 orders of magnitude when used either prophylactically or on established 24-hour biofilms. In addition, PelAh was able to increase neutrophil killing by ~50%. This work illustrates the feasibility and benefits of using bacterial exopolysaccharide biosynthetic glycoside hydrolases to develop novel antibiofilm therapeutics. PMID:27386527

46 CFR 197.515 - Permissible exposure limits (PELs).

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Permissible exposure limits (PELs). 197.515 Section 197.515 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE OCCUPATIONAL SAFETY AND HEALTH STANDARDS GENERAL PROVISIONS Benzene § 197.515 Permissible exposure limits (PELs). The permissible...

46 CFR 197.515 - Permissible exposure limits (PELs).

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Permissible exposure limits (PELs). 197.515 Section 197.515 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE OCCUPATIONAL SAFETY AND HEALTH STANDARDS GENERAL PROVISIONS Benzene § 197.515 Permissible exposure limits (PELs). The permissible...

46 CFR 197.515 - Permissible exposure limits (PELs).

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Permissible exposure limits (PELs). 197.515 Section 197.515 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE OCCUPATIONAL SAFETY AND HEALTH STANDARDS GENERAL PROVISIONS Benzene § 197.515 Permissible exposure limits (PELs). The permissible...

46 CFR 197.515 - Permissible exposure limits (PELs).

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Permissible exposure limits (PELs). 197.515 Section 197.515 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE OCCUPATIONAL SAFETY AND HEALTH STANDARDS GENERAL PROVISIONS Benzene § 197.515 Permissible exposure limits (PELs). The permissible...

46 CFR 197.515 - Permissible exposure limits (PELs).

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Permissible exposure limits (PELs). 197.515 Section 197.515 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE OCCUPATIONAL SAFETY AND HEALTH STANDARDS GENERAL PROVISIONS Benzene § 197.515 Permissible exposure limits (PELs). The permissible...

Energy landscape-driven non-equilibrium evolution of inherent structure in disordered material

DOE PAGES

Fan, Yue; Iwashita, Takuya; Egami, Takeshi

2017-05-19

Complex states in glasses can be neatly expressed by the potential energy landscape (PEL). But, because PEL is highly multi-dimensional it is difficult to describe how the system moves around in PEL. We demonstrate that it is possible to predict the evolution of macroscopic state in a metallic glass, such as ageing and rejuvenation, through a set of simple equations describing excitations in the PEL. The key to this simplification is the realization that the step of activation from the initial state to the saddle point in PEL and the following step of relaxation to the final state are essentiallymore » decoupled. Furthermore, the model shows that the interplay between activation and relaxation in PEL is the key driving force that simultaneously explains both the equilibrium of supercooled liquid and the thermal hysteresis observed in experiments. It further predicts anomalous peaks in truncated thermal scanning, validated by independent molecular dynamics simulation.« less

Nucleotide sequences, genetic organization, and distribution of pEU30 and pEL60 from Erwinia amylovora.

PubMed

Foster, Gayle C; McGhee, Gayle C; Jones, Alan L; Sundin, George W

2004-12-01

The nucleotide sequences, genetic organization, and distribution of plasmids pEU30 (30,314 bp) and pEL60 (60,145 bp) from the plant pathogen Erwinia amylovora are described. The newly characterized pEU30 and pEL60 plasmids inhabited strains isolated in the western United States and Lebanon, respectively. The gene content of pEU30 resembled plasmids found in plant-associated bacteria, while that of pEL60 was most similar to IncL/M plasmids inhabiting enteric bacteria.

Dynamic Remodeling of Microbial Biofilms by Functionally Distinct Exopolysaccharides

PubMed Central

Chew, Su Chuen; Kundukad, Binu; Seviour, Thomas; van der Maarel, Johan R. C.; Yang, Liang; Rice, Scott A.; Doyle, Patrick

2014-01-01

ABSTRACT Biofilms are densely populated communities of microbial cells protected and held together by a matrix of extracellular polymeric substances. The structure and rheological properties of the matrix at the microscale influence the retention and transport of molecules and cells in the biofilm, thereby dictating population and community behavior. Despite its importance, quantitative descriptions of the matrix microstructure and microrheology are limited. Here, particle-tracking microrheology in combination with genetic approaches was used to spatially and temporally study the rheological contributions of the major exopolysaccharides Pel and Psl in Pseudomonas aeruginosa biofilms. Psl increased the elasticity and effective cross-linking within the matrix, which strengthened its scaffold and appeared to facilitate the formation of microcolonies. Conversely, Pel reduced effective cross-linking within the matrix. Without Psl, the matrix becomes more viscous, which facilitates biofilm spreading. The wild-type biofilm decreased in effective cross-linking over time, which would be advantageous for the spreading and colonization of new surfaces. This suggests that there are regulatory mechanisms to control production of the exopolysaccharides that serve to remodel the matrix of developing biofilms. The exopolysaccharides were also found to have profound effects on the spatial organization and integration of P. aeruginosa in a mixed-species biofilm model of P. aeruginosa-Staphylococcus aureus. Pel was required for close association of the two species in mixed-species microcolonies. In contrast, Psl was important for P. aeruginosa to form single-species biofilms on top of S. aureus biofilms. Our results demonstrate that Pel and Psl have distinct physical properties and functional roles during biofilm formation. PMID:25096883

Physician leadership in e-health? A systematic literature review.

PubMed

Keijser, Wouter; Smits, Jacco; Penterman, Lisanne; Wilderom, Celeste

2016-07-04

Purpose This paper aims to systematically review the literature on roles of physicians in virtual teams (VTs) delivering healthcare for effective "physician e-leadership" (PeL) and implementation of e-health. Design/methodology/approach The analyzed studies were retrieved with explicit keywords and criteria, including snowball sampling. They were synthesized with existing theoretical models on VT research, healthcare team competencies and medical leadership. Findings Six domains for further PeL inquiry are delineated: resources, task processes, socio-emotional processes, leadership in VTs, virtual physician-patient relationship and change management. We show that, to date, PeL studies on socio-technical dynamics and their consequences on e-health are found underrepresented in the health literature; i.e. no single empirical, theoretic or conceptual study with a focus on PeL in virtual healthcare work was identified. Research limitations/implications E-health practices could benefit from organization-behavioral type of research for discerning effective physicians' roles and inter-professional relations and their (so far) seemingly modest but potent impact on e-health developments. Practical implications Although best practices in e-health care have already been identified, this paper shows that physicians' roles in e-health initiatives have not yet received any in-depth study. This raises questions such as are physicians not yet sufficiently involved in e-health? If so, what (dis)advantages may this have for current e-health investments and how can they best become involved in (leading) e-health applications' design and implementation in the field? Originality/value If effective medical leadership is being deployed, e-health effectiveness may be enhanced; this new proposition needs urgent empirical scrutiny.

Matrix polymer species have distinct effects on the mechanics of bacterial biofilms

NASA Astrophysics Data System (ADS)

Kovach, Kristin; Davis-Fields, Megan; Gordon, Vernita

2015-03-01

Biofilms are aggregates of microorganisms embedded in a self-produced extracellular polymer matrix. The matrix confers protection to these microorganisms against mechanical and chemical stresses that they may experience in their environment. The bacterium Pseudomonas aeruginosa is widely used as a model biofilm-forming organism because it is an opportunistic human pathogen common in hospital-acquired infections, in chronic wounds, and in cystic fibrosis lung disease. P. aeruginosa strain PA01 forms biofilms that are primarily structured by the extracellular polysaccharides Pel and Psl. Using bulk rheological measurements, we show that these polysaccharides each play a unique role in the mechanical robustness of the biofilm. Psl increases the elastic storage modulus while Pel increases the ductility of the biofilm. Increased expression of either Psl or Pel increases the yield stress by about the same amount. Identifying the mechanism(s) by which these polymers contribute to the mechanical toughness of the biofilm could allow new approaches to effective biofilm clearance, by revealing targets for disruption that would weaken the biofilm.

Comparative effect of integrated pest management and farmers' standard pest control practice for managing insect pests on cabbage (Brassica spp.).

PubMed

Reddy, Gadi V P

2011-08-01

Studies were conducted on experimental cabbage plantings in 2009 and on experimental and commercial plantings in 2010, comparing farmers' current chemical standard pesticide practices with an integrated pest management (IPM) program based on the use of neem (Aza-Direct) and DiPel (Bacillus thuringiensis). In experimental plantings, the IPM program used six or eight applications of neem and DiPel on a rotational basis. The standard-practice treatments consisted of six or eight applications of carbaryl and malathion or control treatment. The IPM treatments reduced pest populations and damage, resulting in a better yield than with the standard chemical or control treatment. When IPM treatment included three applications of neem plus three applications of DiPel (on a rotational basis in experimental fields), it again reduced the pest population and damage and produced a better yield than the standard practice. The lower input costs of the IPM program resulted in better economic returns in both trials. The IPM components neem and DiPel are suitable for use in an IPM program for managing insect pests on cabbage (Brassica spp.). Copyright © 2011 Society of Chemical Industry.

Analysis of mutational signatures in exomes from B-cell lymphoma cell lines suggest APOBEC3 family members to be involved in the pathogenesis of primary effusion lymphoma

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

Wagener, R.; Alexandrov, L. B.; Montesinos-Rongen, M.

Here, primary effusion lymphoma (PEL) is a rare large B-cell neoplasm particularly affecting immunodeficient hosts with an increased incidence in young or middle-aged males infected with the HIV. 1 The clinical outcome of patients with PEL is unfavorable with a median survival of <6 months. 1 PEL has been closely associated with human herpes virus 8 (HHV8, previously called Kaposi sarcoma herpesvirus) infection. 1 In some cases a coinfection of HHV8 with the Epstein–Barr Virus (EBV) has been described. 1 HHV8 encodes various genes homologous to cellular genes that have proliferative and anti-apoptotic functions. 2 Although HHV8 is supposed tomore » be a major driver of PEL, it alone is not sufficient for a full-blown lymphomagenesis. 2 PEL usually shows complex karyotypes with many chromosomal aberrations. 3 This chromosomal complexity might be driven by the viral infection and lead to genetic alterations cooperating with HHV8 in PEL lymphomagenesis. 4« less

Primary effusion lymphoma-like lymphoma in a patient with inflammatory bowel disease.

PubMed

Nussinson, Elchanan; Shibli, Fahmi; Shahbari, Azmi; Rock, Wasseem; Elias, Mazen; Elmalah, Irit

2014-01-21

A 77-year-old man with inflammatory bowel disease (IBD) and who was treated with anti-tumor necrosis factor (TNF), 6-mercaptopurine and corticosteroids, presented with primary effusion lymphoma-like lymphoma (PEL-like lymphoma) with massive ascites. The patient's clinical course was complicated by acute renal insufficiency and hypotension, which led to death within 2 wk. In general, patients with IBD may have an increased risk for development of lymphoma, which is frequently associated with immunosuppressive and/or anti-TNF antibody therapies. PEL is a rare subset of lymphoma localized to serous body cavities, lacks tumor mass or nodal involvement, and is associated with infection by human herpes virus 8 (HHV-8). Primary neoplastic effusion may also be present in patients with large B-cell lymphoma without evidence of human immunodeficiency virus or HHV-8 infections. This type of lymphoma is classified as PEL-like lymphoma. Both PEL and PEL-like lymphoma types have been reported in patients undergoing immunosuppressive therapy, but to the best of our knowledge, the case described herein represents the first PEL-like lymphoma occurring in a patient with IBD.

Cloning, Expression and Characterization of a Novel Thermophilic Polygalacturonase from Caldicellulosiruptor bescii DSM 6725

PubMed Central

Chen, Yanyan; Sun, Dejun; Zhou, Yulai; Liu, Liping; Han, Weiwei; Zheng, Baisong; Wang, Zhi; Zhang, Zuoming

2014-01-01

We cloned the gene ACM61449 from anaerobic, thermophilic Caldicellulosiruptor bescii, and expressed it in Escherichia coli origami (DE3). After purification through thermal treatment and Ni-NTA agarose column extraction, we characterized the properties of the recombinant protein (CbPelA). The optimal temperature and pH of the protein were 72 °C and 5.2, respectively. CbPelA demonstrated high thermal-stability, with a half-life of 14 h at 70 °C. CbPelA also showed very high activity for polygalacturonic acid (PGA), and released monogalacturonic acid as its sole product. The Vmax and Km of CbPelA were 384.6 U·mg−1 and 0.31 mg·mL−1, respectively. CbPelA was also able to hydrolyze methylated pectin (48% and 10% relative activity on 20%–34% and 85% methylated pectin, respectively). The high thermo-activity and methylated pectin hydrolization activity of CbPelA suggest that it has potential applications in the food and textile industry. PMID:24705464

Primary effusion lymphoma-like lymphoma in a patient with inflammatory bowel disease

PubMed Central

Nussinson, Elchanan; Shibli, Fahmi; Shahbari, Azmi; Rock, Wasseem; Elias, Mazen; Elmalah, Irit

2014-01-01

A 77-year-old man with inflammatory bowel disease (IBD) and who was treated with anti-tumor necrosis factor (TNF), 6-mercaptopurine and corticosteroids, presented with primary effusion lymphoma-like lymphoma (PEL-like lymphoma) with massive ascites. The patient’s clinical course was complicated by acute renal insufficiency and hypotension, which led to death within 2 wk. In general, patients with IBD may have an increased risk for development of lymphoma, which is frequently associated with immunosuppressive and/or anti-TNF antibody therapies. PEL is a rare subset of lymphoma localized to serous body cavities, lacks tumor mass or nodal involvement, and is associated with infection by human herpes virus 8 (HHV-8). Primary neoplastic effusion may also be present in patients with large B-cell lymphoma without evidence of human immunodeficiency virus or HHV-8 infections. This type of lymphoma is classified as PEL-like lymphoma. Both PEL and PEL-like lymphoma types have been reported in patients undergoing immunosuppressive therapy, but to the best of our knowledge, the case described herein represents the first PEL-like lymphoma occurring in a patient with IBD. PMID:24574759

Analysis of mutational signatures in exomes from B-cell lymphoma cell lines suggest APOBEC3 family members to be involved in the pathogenesis of primary effusion lymphoma

DOE PAGES

Wagener, R.; Alexandrov, L. B.; Montesinos-Rongen, M.; ...

2015-02-04

Here, primary effusion lymphoma (PEL) is a rare large B-cell neoplasm particularly affecting immunodeficient hosts with an increased incidence in young or middle-aged males infected with the HIV. 1 The clinical outcome of patients with PEL is unfavorable with a median survival of <6 months. 1 PEL has been closely associated with human herpes virus 8 (HHV8, previously called Kaposi sarcoma herpesvirus) infection. 1 In some cases a coinfection of HHV8 with the Epstein–Barr Virus (EBV) has been described. 1 HHV8 encodes various genes homologous to cellular genes that have proliferative and anti-apoptotic functions. 2 Although HHV8 is supposed tomore » be a major driver of PEL, it alone is not sufficient for a full-blown lymphomagenesis. 2 PEL usually shows complex karyotypes with many chromosomal aberrations. 3 This chromosomal complexity might be driven by the viral infection and lead to genetic alterations cooperating with HHV8 in PEL lymphomagenesis. 4« less

Structure-based engineering of a pectate lyase with improved specific activity for ramie degumming.

PubMed

Zhou, Zhanping; Liu, Yang; Chang, Zhenying; Wang, Huilin; Leier, André; Marquez-Lago, Tatiana T; Ma, Yanhe; Li, Jian; Song, Jiangning

2017-04-01

Biotechnological applications of microbial pectate lyases (Pels) in plant fiber processing are promising, eco-friendly substitutes for conventional chemical degumming processes. However, to potentiate the enzymes' use for industrial applications, resolving the molecular structure to elucidate catalytic mechanisms becomes necessary. In this manuscript, we report the high resolution (1.45 Å) crystal structure of pectate lyase (pelN) from Paenibacillus sp. 0602 in apo form. Through sequence alignment and structural superposition with other members of the polysaccharide lyase (PL) family 1 (PL1), we determined that pelN shares the characteristic right-handed β-helix and is structurally similar to other members of the PL1 family, while exhibiting key differences in terms of catalytic and substrate binding residues. Then, based on information from structure alignments with other PLs, we engineered a novel pelN. Our rational design yielded a pelN mutant with a temperature for enzymatic activity optimally shifted from 67.5 to 60 °C. Most importantly, this pelN mutant displayed both higher specific activity and ramie fiber degumming ability when compared with the wild-type enzyme. Altogether, our rational design method shows great potential for industrial applications. Moreover, we expect the reported high-resolution crystal structure to provide a solid foundation for future rational, structure-based engineering of genetically enhanced pelNs.

The effects of temperature and pressure on airborne exposure concentrations when performing compliance evaluations using ACGIH TLVs and OSHA PELs.

PubMed

Stephenson, D J; Lillquist, D R

2001-04-01

Occupational hygienists perform air sampling to characterize airborne contaminant emissions, assess occupational exposures, and establish allowable workplace airborne exposure concentrations. To perform these air sampling applications, occupational hygienists often compare an airborne exposure concentration to a corresponding American Conference of Governmental Industrial Hygienists (ACGIH) threshold limit value (TLV) or an Occupational Safety and Health Administration (OSHA) permissible exposure limit (PEL). To perform such comparisons, one must understand the physiological assumptions used to establish these occupational exposure limits, the relationship between a workplace airborne exposure concentration and its associated TLV or PEL, and the effect of temperature and pressure on the performance of an accurate compliance evaluation. This article illustrates the correct procedure for performing compliance evaluations using airborne exposure concentrations expressed in both parts per million and milligrams per cubic meter. In so doing, a brief discussion is given on the physiological assumptions used to establish TLVs and PELs. It is further shown how an accurate compliance evaluation is fundamentally based on comparison of a measured work site exposure dose (derived from the sampling site exposure concentration estimate) to an estimated acceptable exposure dose (derived from the occupational exposure limit concentration). In addition, this article correctly illustrates the effect that atmospheric temperature and pressure have on airborne exposure concentrations and the eventual performance of a compliance evaluation. This article also reveals that under fairly moderate conditions of temperature and pressure, 30 degrees C and 670 torr, a misunderstanding of how varying atmospheric conditions affect concentration values can lead to a 15 percent error in assessing compliance.

vPELS: An E-Learning Social Environment for VLSI Design with Content Security Using DRM

ERIC Educational Resources Information Center

Dewan, Jahangir; Chowdhury, Morshed; Batten, Lynn

2014-01-01

This article provides a proposal for personal e-learning system (vPELS [where "v" stands for VLSI: very large scale integrated circuit])) architecture in the context of social network environment for VLSI Design. The main objective of vPELS is to develop individual skills on a specific subject--say, VLSI--and share resources with peers.…

Paid Educational Leave: An International Perspective. Second J. Roby Kidd Lecture, Windsor, Oct. 31 - Nov. 1, 1977

ERIC Educational Resources Information Center

Bengtsson, Jarl

1978-01-01

First discusses three major controversies regarding paid educational leave (PEL), then reviews the major findings of two studies involving ten countries where PEL has been implemented. Finally, future problems and issues are covered, particularly PEL in relation to industrial democratization as well as a new mixture of work and non-work time. (EM)

NASA Space Radiation Protection Strategies: Risk Assessment and Permissible Exposure Limits

NASA Technical Reports Server (NTRS)

Huff, J. L.; Patel, Z. S.; Simonsen, L. C.

2017-01-01

Permissible exposure limits (PELs) for short-term and career astronaut exposures to space radiation have been set and approved by NASA with the goal of protecting astronauts against health risks associated with ionizing radiation exposure. Short term PELs are intended to prevent clinically significant deterministic health effects, including performance decrements, which could threaten astronaut health and jeopardize mission success. Career PELs are implemented to control late occurring health effects, including a 3% risk of exposure induced death (REID) from cancer, and dose limits are used to prevent cardiovascular and central nervous system diseases. For radiation protection, meeting the cancer PEL is currently the design driver for galactic cosmic ray and solar particle event shielding, mission duration, and crew certification (e.g., 1-year ISS missions). The risk of cancer development is the largest known long-term health consequence following radiation exposure, and current estimates for long-term health risks due to cardiovascular diseases are approximately 30% to 40% of the cancer risk for exposures above an estimated threshold (Deep Space one-year and Mars missions). Large uncertainties currently exist in estimating the health risks of space radiation exposure. Improved understanding through radiobiology and physics research allows increased accuracy in risk estimation and is essential for ensuring astronaut health as well as for controlling mission costs, optimization of mission operations, vehicle design, and countermeasure assessment. We will review the Space Radiation Program Element's research strategies to increase accuracy in risk models and to inform development and validation of the permissible exposure limits.

Styrene vapor control systems in FRP yacht plants.

PubMed

Todd, W F

1985-01-01

The production of large (greater than 25-ft) fiber-reinforced plastic (FRP) yachts has presented problems of styrene exposure in excess of the Occupational Safety and Health Administration permissible exposure level (OSHA PEL) of 100 ppm. Also, the National Institute for Occupational Safety and Health (NIOSH) is currently recommending a 10-hour workshift, 40-hour workweek time weighted average (TWA) of 50 ppm for styrene. Meeting this challenge will require a system of engineering, work practice, personal protective equipment, and monitoring control measures. NIOSH has performed a study of the engineering controls in three FRP yacht plants. Work practices and the use of personal protective equipment (PPE) were also considered in the evaluation. The three systems evaluated included a dilution system, a local ventilation system, and a push-pull ventilation system. The cost of constructing and operating these systems was not evaluated in this study. Study results indicated that each type of ventilation system can meet the present PEL of 100 ppm styrene; however, it is not certain that these systems can meet a lower PEL of 50 ppm styrene.

Characterization of Erwinia chrysanthemi by pectinolytic isozyme polymorphism and restriction fragment length polymorphism analysis of PCR-amplified fragments of pel genes.

PubMed Central

Nassar, A; Darrasse, A; Lemattre, M; Kotoujansky, A; Dervin, C; Vedel, R; Bertheau, Y

1996-01-01

Conserved regions about 420 bp long of the pelADE cluster specific to Erwinia chrysanthemi were amplified by PCR and used to differentiate 78 strains of E. chrysanthemi that were obtained from different hosts and geographical areas. No PCR products were obtained from DNA samples extracted from other pectinolytic and nonpectinolytic species and genera. The pel fragments amplified from the E. chrysanthemi strains studied were compared by performing a restriction fragment length polymorphism (RFLP) analysis. On the basis of similarity coefficients derived from the RFLP analysis, the strains were separated into 16 PCR RFLP patterns grouped in six clusters, These clusters appeared to be correlated with other infraspecific levels of E. chrysanthemi classification, such as pathovar and biovar, and occasionally with geographical origin. Moreover, the clusters correlated well with the polymorphism of pectate lyase and pectin methylesterase isoenzymes. While the pectin methylesterase profiles correlated with host monocot-dicot classification, the pectate lyase polymorphism might reflect the cell wall microdomains of the plants belonging to these classes. PMID:8779560

The Philadelphia Education Longitudinal Study (PELS): Report on the Transition to High School in the School District of Philadelphia.

ERIC Educational Resources Information Center

Neild, Ruth Curran; Weiss, Christopher C.

The Philadelphia Education Longitudinal Study (PELS) on the transition to ninth grade in Philadelphia highlights the high school choice process, course failure rates during ninth grade, and parents' responses to the transition to high school. The PELS study followed a city-wide random sample of public school students from the summer after eighth…

PEL Staff Together for the First Time | Poster

Cancer.gov

By Ashley DeVine, Staff Writer John-Paul Denson and Troy Taylor of the Protein Expression Laboratory (PEL) used to pack liters of Escherichia coli lysates on ice, put them in the back of a microvan, and drive across campus to deliver the samples for protein purification. Now that all PEL staff members are working under the same roof at the Advanced Technology Research Facility

Regulation of the production of extracellular pectinase, cellulase, and protease in the soft rot bacterium Erwinia carotovora subsp. carotovora: evidence that aepH of E. carotovora subsp. carotovora 71 activates gene expression in E. carotovora subsp. carotovora, E. carotovora subsp. atroseptica, and Escherichia coli.

PubMed Central

Murata, H; Chatterjee, A; Liu, Y; Chatterjee, A K

1994-01-01

The production of pectolytic enzymes (pectate lyase [Pel] and polygalacturonase [Peh]), cellulase (Cel), and protease (Prt) is activated in the soft rot bacterium Erwinia carotovora subsp. carotovora by aepA (activator of extracellular protein production) and celery extract (Y. Liu, H. Murata, A. Chatterjee, and A. K. Chatterjee, Mol. Plant-Microbe Interact. 6:299-308, 1993). We recently isolated a new class of mutants of strain E. carotovora subsp. carotovora 71 which overproduces Pel, Peh, Cel, and Prt. From the overproducing strain AC5034, we identified an activator locus, designated aepH*, which stimulated Pel, Peh, Cel, and Prt production in E. carotovora subsp. carotovora 71 or its derivatives. The nucleotide sequence of the aepH* DNA segment revealed an open reading frame of 141 bp that could encode a small (5.45-kDa) highly basic (pI 11.7) protein of 47 amino acid residues. Analyses of deletions and MudI insertions indicated that the activator function required the 508-bp DNA segment which contains this open reading frame. The wild-type locus, aepH+, is localized within a DNA segment upstream of aepA. An AepH- strain constructed by exchanging aepH+ with aepH*::MudI was deficient in Pel, Peh, Cel, and Prt production; exoenzyme production was restored upon the introduction of a plasmid carrying aepH+ or aepH*. Plasmids carrying either aepH+ or aepH* activated the production of Pel-1, Peh-1, and Cel in Escherichia coli HB101 carrying the cognate genes. The aepH effect in E. coli was due to the activation of transcription, as indicated by assays of pel-1 and peh-1 mRNAs. The aepH+ and aepH* plasmids also stimulated Pel, Peh, Cel, and Prt production in other wild-type E. carotovora subsp. carotovora strains as well as in E. carotovora subsp. atroseptica. Although the stimulatory effect was generally more pronounced with aepH* than with aepH+, the extent of activation in the wild-type strains depended upon the bacterial strain and the growth medium. Southern blot hybridization revealed the presence of aepH homologs in E. carotovora subsp. carotovora and E. carotovora subsp. atroseptica, and provided physical evidence for linkage between aepA and aepH homologs in genomes of these bacteria. We conclude that aepH-mediated activation of exoprotein gene expression is a feature common to most strains of E. carotovora. Images PMID:7944360

Crystal structure of a triacylglycerol lipase from Penicillium expansum at 1.3 A determined by sulfur SAD

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

Bian, Chuanbing; Yuan, Cai; Chen, Liqing

2010-04-05

Triacylglycerol lipases (EC 3.1.1.3) are present in many different organisms including animals, plants, and microbes. Lipases catalyze the hydrolysis of long-chain triglycerides into fatty acids and glycerol at the interface between the water insoluble substrate and the aqueous phase. Lipases can also catalyze the reverse esterification reaction to form glycerides under certain conditions. Lipases of microbial origin are of considerable commercial interest for wide variety of biotechnological applications in industries, including detergent, food, cosmetic, pharmaceutical, fine chemicals, and biodiesel. Nowadays, microbial lipases have become one of the most important industrial enzymes. PEL (Penicillium expansum lipase) is a fungal lipase frommore » Penicillium expansum strain PF898 isolated from Chinese soil that has been subjected to several generations of mutagenesis to increase its enzymatic activity. PEL belongs to the triacylglycerol lipases family, and its catalytic characteristics have been studied. The enzyme has been used in Chinese laundry detergent industry for several years (http://www.leveking.com). However, the poor thermal stability of the enzyme limits its application. To further study and improve this enzyme, PEL was cloned and sequenced. Furthermore, it was overexpressed in Pichia pastoris. PEL contains GHSLG sequence, which is the lipase consensus sequence Gly-X1-Ser-X2-Gly, but has a low amino acid sequence identities to other lipases. The most similar lipases are Rhizomucor miehei (PML) and Rhizopus niveus (PNL) with a 21% and 20% sequence identities to PEL, respectively. Interestingly, the similarity of PEL with the known esterases is somewhat higher with 24% sequence identity to feruloyl esterase A. Here, we report the 1.3 {angstrom} resolution crystal structure of PEL determined by sulfur SAD phasing. This structure not only presents a new lipase structure at high resolution, but also provides a structural platform to analyze the published mutagenesis results. The structure may also open up new avenues for future protein engineering study on PEL.« less

KSHV LANA and EBV LMP1 induce the expression of UCH-L1 following viral transformation

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

Bentz, Gretchen L.; Bheda-Malge, Anjali; Wang, Ling

Ubiquitin C-terminal Hydrolase L1 (UCH-L1) has oncogenic properties and is highly expressed during malignancies. We recently documented that Epstein-Barr virus (EBV) infection induces uch-l1 expression. Here we show that Kaposi's Sarcoma-associated herpesvirus (KSHV) infection induced UCH-L1 expression, via cooperation of KSHV Latency-Associated Nuclear Antigen (LANA) and RBP-Jκ and activation of the uch-l1 promoter. UCH-L1 expression was also increased in Primary Effusion Lymphoma (PEL) cells co-infected with KSHV and EBV compared with PEL cells infected only with KSHV, suggesting EBV augments the effect of LANA on uch-l1. EBV latent membrane protein 1 (LMP1) is one of the few EBV products expressedmore » in PEL cells. Results showed that LMP1 was sufficient to induce uch-l1 expression, and co-expression of LMP1 and LANA had an additive effect on uch-l1 expression. These results indicate that viral latency products of both human γ-herpesviruses contribute to uch-l1 expression, which may contribute to the progression of lymphoid malignancies. - Highlights: • Infection of endothelial cells with KSHV induced UCH-L1 expression. • KSHV LANA is sufficient for the induction of uch-l1. • Co-infection with KSHV and EBV (observed in some PELs) results in the additive induction of uch-l1. • EBV LMP1 also induced UCH-L1 expression. • LANA- and LMP1-mediated activation of the uch-l1 promoter is in part through RBP-Jκ.« less

Exposure assessment of JAVELIN missile combustion products

NASA Astrophysics Data System (ADS)

Lundy, Donald O.; Langford, Roland E.

1994-02-01

Characterization and analysis of combustion products resulting from firing the JAVELIN missile were performed. Of those combustion products analyzed, it was determined that airborne lead concentrations exceeded the OSHA PEL of 50 micrograms each time the missile was fired while in the enclosure. Since the OSHA PEL standard is based upon a continuous rather than a short-term exposures blood lead concentrations were sought to ascertain the relationship between a short duration airborne exposure and its physiological effect on the body. Blood lead levels were taken on 49 test subjects prior to various JAVELIN missile test firings. Of those 49, 21 were outfitted With personal sampling equipment to determine airborne concentrations at the Assistant Gunner and Gunner positions. Periodic blood sampling after a single exposure showed an average increase of 2.27 micrograms/dL for all test subjects. Recommendations were made to consider changes in the positioning of the enclosure inhabitants to minimize airborne lead concentrations, to limit the number of missiles fired (situation dependent), and replacement of the lead B-resorcyolate with a non-lead containing burn rate modifier for the launch motor.

Alternating current electroosmotic flow in polyelectrolyte-grafted nanochannel.

PubMed

Li, Fengqin; Jian, Yongjun; Chang, Long; Zhao, Guangpu; Yang, Liangui

2016-11-01

In this work, we investigate the time periodic electroosmotic flow (EOF) of an electrolyte solution through a slit polyelectrolyte-grafted (PE-grafted) nanochannel under applied alternating current (AC) electrical field. The PE-grafted nanochannel is represented by a rigid surface covered by a polyelectrolyte layer (PEL) in a brush-like configuration. Under Debye-Hückel approximation, we obtain analytical solutions of electrical potential in decoupled regime of PE-grafted nanochannel, where the thickness of PEL is independent of the electrostatic effects triggered by polyelectrolyte charges. Based upon the electrical potential obtained above, we calculate EOF velocities with uniform and non-uniform drag coefficients for PE-grafted nanochannel and compare their results. The effects of pertinent dimensionless parameters on EOF velocity amplitude are discussed in detail. Moreover, the amplitude of EOF velocity in a PE-grafted nanochannel is compared with that in a rigid one. It is shown that larger EOF velocity and volume flow rate are found for a PE-grafted nanochannel. In addition, AC EOF velocity is further investigated. The oscillation of velocity reduces and is restricted within the region near the PEL-electrolyte interface for higher oscillating Reynolds number Re. Copyright © 2016 Elsevier B.V. All rights reserved.

Toxicities and risk assessment of heavy metals in sediments of Taihu Lake, China, based on sediment quality guidelines.

PubMed

Zhang, Yanfeng; Han, Yuwei; Yang, Jinxi; Zhu, Lingyan; Zhong, Wenjue

2017-12-01

The occurrence, toxicities, and ecological risks of five heavy metals (Pb, Cu, Cd, Zn and Ni) in the sediment of Taihu Lake were investigated in this study. To evaluate the toxicities caused by the heavy metals, the toxicities induced by organic contaminants and ammonia in the sediments were screened out with activated carbon and zeolite. The toxicities of heavy metals in sediments were tested with benthic invertebrates (tubificid and chironomid). The correlations between toxicity of sediment and the sediment quality guidelines (SQGs) derived previously were evaluated. There were significant correlations (p<0.0001) between the observed toxicities and the total risk quotients of the heavy metals based on SQGs, indicating that threshold effect level (TEL) and probable effect level (PEL) were reliable to predict the toxicities of heavy metals in the sediments of Taihu Lake. By contrast, the method based on acid volatile sulfides (AVS) and simultaneously extracted metals (SEM), such as ∑SEM/AVS and ∑SEM-AVS, did not show correlations with the toxicities. Moreover, the predictive ability of SQGs was confirmed by a total predicting accuracy of 77%. Ecological risk assessment based on TELs and PELs showed that the contaminations of Pb, Cu, Cd and Zn in the sediments of Taihu Lake were at relatively low or medium levels. The risks caused by heavy metals in the sediments of northern bay of the lake, which received more wastewater discharge from upper stream, were higher than other area of the lake. Copyright © 2017. Published by Elsevier B.V.

Replacement of Chromium Electroplating on Gas Turbine Engine Components using Thermal Spray Coatings

DTIC Science & Technology

2006-05-01

studies have clearly shown that there are a significant number of excess deaths at the current PEL of 100...under the coordination of the Naval Sea Systems Command (NAVSEA) studied the technical and economic impact of a reduction in the hex-Cr PEL. At the...finishing industry and the study conducted by NAVSEA in 1995, it is clear that a reduction of the hex-Cr PEL to a range near 1 µg/m3 will greatly

Climatic variability in Princess Elizabeth Land (East Antarctica) over the last 350 years

NASA Astrophysics Data System (ADS)

Ekaykin, Alexey A.; Vladimirova, Diana O.; Lipenkov, Vladimir Y.; Masson-Delmotte, Valérie

2017-01-01

We use isotopic composition (δD) data from six sites in Princess Elizabeth Land (PEL) in order to reconstruct air temperature variability in this sector of East Antarctica over the last 350 years. First, we use the present-day instrumental mean annual surface air temperature data to demonstrate that the studied region (between Russia's Progress, Vostok and Mirny research stations) is characterized by uniform temperature variability. We thus construct a stacked record of the temperature anomaly for the whole sector for the period of 1958-2015. A comparison of this series with the Southern Hemisphere climatic indices shows that the short-term inter-annual temperature variability is primarily governed by the Antarctic Oscillation (AAO) and Interdecadal Pacific Oscillation (IPO) modes of atmospheric variability. However, the low-frequency temperature variability (with period > 27 years) is mainly related to the anomalies of the Indian Ocean Dipole (IOD) mode. We then construct a stacked record of δD for the PEL for the period of 1654-2009 from individual normalized and filtered isotopic records obtained at six different sites (PEL2016 stacked record). We use a linear regression of this record and the stacked PEL temperature record (with an apparent slope of 9 ± 5.4 ‰ °C-1) to convert PEL2016 into a temperature scale. Analysis of PEL2016 shows a 1 ± 0.6 °C warming in this region over the last 3 centuries, with a particularly cold period from the mid-18th to the mid-19th century. A peak of cooling occurred in the 1840s - a feature previously observed in other Antarctic records. We reveal that PEL2016 correlates with a low-frequency component of IOD and suggest that the IOD mode influences the Antarctic climate by modulating the activity of cyclones that bring heat and moisture to Antarctica. We also compare PEL2016 with other Antarctic stacked isotopic records. This work is a contribution to the PAGES (Past Global Changes) and IPICS (International Partnerships in Ice Core Sciences) Antarctica 2k projects.

Multilocus analysis using putative fungal effectors to describe a population of Fusarium oxysporum from sugar beet.

PubMed

Covey, Paul A; Kuwitzky, Brett; Hanson, Mia; Webb, Kimberly M

2014-08-01

Sugar beet (Beta vulgaris) Fusarium yellows is caused by Fusarium oxysporum f. sp. betae and can lead to significant reductions in root yield, sucrose percentage, juice purity, and storability. F. oxysporum f. sp. betae can be highly variable and many F. oxysporum strains isolated from symptomatic sugar beet are nonpathogenic. Identifying pathogenicity factors and their diversity in the F. oxysporum f. sp. betae population could further understanding of how this pathogen causes disease and potentially provide molecular markers to rapidly identify pathogenic isolates. This study used several previously described fungal effector genes (Fmk1, Fow1, Pda1, PelA, PelD, Pep1, Prt1, Rho1, Sge1, Six1, Six6, Snf1, and Ste12) as genetic markers, in a population of 26 pathogenic and nonpathogenic isolates of F. oxysporum originally isolated from symptomatic sugar beet. Of the genes investigated, six were present in all F. oxysporum isolates from sugar beet (Fmk1, Fow1, PelA, Rho1, Snf1, and Ste12), and seven were found to be dispersed within the population (Pda1, PelD, Pep1, Prt1, Sge1, Six1, and Six6). Of these, Fmk1, Fow1, PelA, Rho1, Sge1, Snf1, and Ste12 were significant in relating clade designations and PelD, and Prt1 were significant for correlating with pathogenicity in F. oxysporum f. sp. betae.

pelB gene in isolates of Colletotrichum gloeosporioides from several hosts.

PubMed

Medeiros, L V; Maciel, D B; Medeiros, V V; Houllou Kido, L M; Oliveira, N T

2010-04-13

Colletotrichum gloeosporioides is an important pathogen for a great number of economically important crops. During the necrotrophic phase of infection by Colletotrichum spp, the degradative enzymes of plant cell walls, such as pectate lyase, clearly increase. A gene pelB that expresses a pectate lyase was identified in isolates of C. gloeosporioides in avocado pathogens. Various molecular studies have identified a kind of specialization of C. gloeosporioides isolates with specific hosts; however, there have been no studies of this gene in isolates from hosts other than avocado. The same is true for other species of Colletotrichum. We examined genetic variability in order to design primers that would amplify pelB gene fragments and compared the products of this amplification in C. gloeosporioides isolates from different hosts. Genetic variability was assessed using ISSR primers; the resultant data were grouped based on the UPGMA clustering method. Primers for the pelB gene were designed from selected GenBank sequences using the Primer 3 program at an annealing temperature of 60 degrees C and product amplification of nearly 600 bp. The ISSR primers were efficient in demonstrating the genetic variability of the Colletotrichum isolates and in distinguishing C. gloeosporioides, C. acutatum and C. sublineolum species. The gene pelB was found in C. gloeosporioides, C. acutatum and C. sublineolum. Amplified restriction fragments using MspI did not reveal differences in pelB gene structure in isolates from the three different host species that we investigated.

Inhibition of autophagy by chloroquine induces apoptosis in primary effusion lymphoma in vitro and in vivo through induction of endoplasmic reticulum stress.

PubMed

Masud Alam, Md; Kariya, Ryusho; Kawaguchi, Azusa; Matsuda, Kouki; Kudo, Eriko; Okada, Seiji

2016-10-01

Autophagy plays a crucial role in cancer cell survival and the inhibition of autophagy is attracting attention as an emerging strategy for the treatment of cancer. Chloroquine (CQ) is an anti-malarial drug, and is also known as an inhibitor of autophagy. Recently, it has been found that CQ induces cancer cell death through the inhibition of autophagy; however, the underlying mechanism is not entirely understood. In this study, we identified the role of CQ-induced cancer cell death using Primary Effusion Lymphoma (PEL) cells. We found that a CQ treatment induced caspase-dependent apoptosis in vitro. CQ also suppressed PEL cell growth in a PEL xenograft mouse model. We showed that CQ activated endoplasmic reticulum (ER) stress signal pathways and induced CHOP, which is an inducer of apoptosis. CQ-induced cell death was significantly decreased by salbrinal, an ER stress inhibitor, indicating that CQ-induced apoptosis in PEL cells depended on ER stress. We show here for the first time that the inhibition of autophagy induces ER stress-mediated apoptosis in PEL cells. Thus, the inhibition of autophagy is a novel strategy for cancer chemotherapy.

PEL Staff Together for the First Time | Poster

Cancer.gov

By Ashley DeVine, Staff Writer John-Paul Denson and Troy Taylor of the Protein Expression Laboratory (PEL) used to pack liters of Escherichia coli lysates on ice, put them in the back of a microvan, and drive across campus to deliver the samples for protein purification. Now that all PEL staff members are working under the same roof at the Advanced Technology Research Facility (ATRF), transferring samples is just a walk down the hall. Staff members were previously spread out in five buildings across the Fort Detrick campus.

Effect of Ammonia Production by Colletotrichum gloeosporioides on pelB Activation, Pectate Lyase Secretion, and Fruit Pathogenicity

PubMed Central

Kramer-Haimovich, H.; Servi, E.; Katan, T.; Rollins, J.; Okon, Y.; Prusky, D.

2006-01-01

The accumulation of ammonia and associated tissue alkalinization predispose avocado fruit to attack by Colletotrichum gloeosporioides. Secretion of ammonia by C. gloeosporioides in the presence of KNO3 was induced by decreasing the pH from 7.0 to 4.0. When the fungus was grown at pH 4.0 or 6.0 in the absence of a nitrogen source, ammonia did not accumulate, and neither pelB (encoding pectate lyase) transcription nor pectate lyase secretion was detected. Under these nitrogen starvation conditions, only transcriptional activation of areA, which encodes the global nitrogen regulator, was detected. pelB transcription and pectate lyase secretion were both detected when C. gloeosporioides was grown at pH 6.0 in the presence of ammonia accumulated from different nitrogen sources. The early accumulation of ammonia induced early pelB expression and pectate lyase secretion. As the external pH increased from 4.0 to 6.0, transcripts of pac1, the C. gloeosporioides pacC homolog, also could be detected. Nit mutants of C. gloeosporioides, which cannot utilize KNO3 as a nitrogen source, did not secrete ammonia, alkalinize the medium, or secrete pectate lyase. If Nit mutants were grown at pH 6.0 in the presence of glutamate, then pectate lyase secretion was induced. Infiltration of 0.1 M ammonium hydroxide at pH 10 into ripening avocado fruits enhanced the activation of quiescent infection and symptom development by C. gloeosporioides. These results suggest that ambient pH alkalinization resulting from ammonia accumulation and the availability of ammonia as a nitrogen source independently regulate pelB expression, pectate lyase secretion, and virulence of C. gloeosporioides. These data suggest that alkalinization during C. gloeosporioides infection is important for its transformation from the quiescent biotrophic stage to the necrotrophic stage of fungal colonization in the fruit host. PMID:16461646

24 CFR 990.245 - Types of appeals.

Code of Federal Regulations, 2011 CFR

2011-04-01

... variance of ten percent or greater in its PEL. (d) Appeal for changing market conditions. A PHA may appeal... may appeal its PEL if it can produce actual project cost data derived from actual asset management, as...

Combined electroosmotically and pressure driven flow in soft nanofluidics.

PubMed

Matin, Meisam Habibi; Ohshima, Hiroyuki

2015-12-15

The present study is devoted to the analysis of mixed electroosmotic and pressure driven flows through a soft charged nanochannel considering boundary slip and constant charge density on the walls of the slit channel. The sources of the fluid flow are the pressure gradient along the channel axis and the electrokinetic effects that trigger an electroosmotic flow under the influence of a uniformly applied electric field. The polyelectrolyte layer (PEL) is denoted as a fixed charge layer (FCL) and the electrolyte ions can be present both inside and outside the PEL i.e., the PEL-electrolyte interface acts as a semi-penetrable membrane. The Poisson-Boltzmann equation is solved assuming the Debye-Hückel linearization for the low electric potential to provide us with analytical closed form solutions for the conservation equations. The conservation equations are solved to obtain the electric potential and velocity distributions in terms of governing dimensionless parameters. The results for the dimensionless electric potential, the dimensionless velocity and Poiseuille number are presented graphically and discussed in detail. Copyright © 2015 Elsevier Inc. All rights reserved.

29 CFR 1910.1050 - Methylenedianiline.

Code of Federal Regulations, 2011 CFR

2011-07-01

... determined by any 15 minute sample period. (c) Permissible exposure limits (PEL). The employer shall assure...) Where the employer can document that exposure levels are equivalent for similar operations in different... paragraph (m) of this section, and explain the information contained in appendix C; and (C) Describe the...

Facultative Control of Matrix Production Optimizes Competitive Fitness in Pseudomonas aeruginosa PA14 Biofilm Models

PubMed Central

Madsen, Jonas S.; Lin, Yu-Cheng; Squyres, Georgia R.; Price-Whelan, Alexa; de Santiago Torio, Ana; Song, Angela; Cornell, William C.; Sørensen, Søren J.

2015-01-01

As biofilms grow, resident cells inevitably face the challenge of resource limitation. In the opportunistic pathogen Pseudomonas aeruginosa PA14, electron acceptor availability affects matrix production and, as a result, biofilm morphogenesis. The secreted matrix polysaccharide Pel is required for pellicle formation and for colony wrinkling, two activities that promote access to O2. We examined the exploitability and evolvability of Pel production at the air-liquid interface (during pellicle formation) and on solid surfaces (during colony formation). Although Pel contributes to the developmental response to electron acceptor limitation in both biofilm formation regimes, we found variation in the exploitability of its production and necessity for competitive fitness between the two systems. The wild type showed a competitive advantage against a non-Pel-producing mutant in pellicles but no advantage in colonies. Adaptation to the pellicle environment selected for mutants with a competitive advantage against the wild type in pellicles but also caused a severe disadvantage in colonies, even in wrinkled colony centers. Evolution in the colony center produced divergent phenotypes, while adaptation to the colony edge produced mutants with clear competitive advantages against the wild type in this O2-replete niche. In general, the structurally heterogeneous colony environment promoted more diversification than the more homogeneous pellicle. These results suggest that the role of Pel in community structure formation in response to electron acceptor limitation is unique to specific biofilm models and that the facultative control of Pel production is required for PA14 to maintain optimum benefit in different types of communities. PMID:26431965

Facultative control of matrix production optimizes competitive fitness in Pseudomonas aeruginosa PA14 biofilm models.

PubMed

Madsen, Jonas S; Lin, Yu-Cheng; Squyres, Georgia R; Price-Whelan, Alexa; de Santiago Torio, Ana; Song, Angela; Cornell, William C; Sørensen, Søren J; Xavier, Joao B; Dietrich, Lars E P

2015-12-01

As biofilms grow, resident cells inevitably face the challenge of resource limitation. In the opportunistic pathogen Pseudomonas aeruginosa PA14, electron acceptor availability affects matrix production and, as a result, biofilm morphogenesis. The secreted matrix polysaccharide Pel is required for pellicle formation and for colony wrinkling, two activities that promote access to O2. We examined the exploitability and evolvability of Pel production at the air-liquid interface (during pellicle formation) and on solid surfaces (during colony formation). Although Pel contributes to the developmental response to electron acceptor limitation in both biofilm formation regimes, we found variation in the exploitability of its production and necessity for competitive fitness between the two systems. The wild type showed a competitive advantage against a non-Pel-producing mutant in pellicles but no advantage in colonies. Adaptation to the pellicle environment selected for mutants with a competitive advantage against the wild type in pellicles but also caused a severe disadvantage in colonies, even in wrinkled colony centers. Evolution in the colony center produced divergent phenotypes, while adaptation to the colony edge produced mutants with clear competitive advantages against the wild type in this O2-replete niche. In general, the structurally heterogeneous colony environment promoted more diversification than the more homogeneous pellicle. These results suggest that the role of Pel in community structure formation in response to electron acceptor limitation is unique to specific biofilm models and that the facultative control of Pel production is required for PA14 to maintain optimum benefit in different types of communities. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Gastroesophageal junction of Anatolian shepherd dog; a study by topographic anatomy, scanning electron and light microscopy.

PubMed

Alsafy, M A M; El-Gendy, S A A

2012-03-01

The aim of this study was to cast a spotlight on the topography and to point out the clinical importance of the gastroesophageal junction (GEJ) in Anatolian Shepherd dogs. Nine Anatolian Shepherd dogs were used to study the morphology of the GEJ. The esophagus was appeared has a portion within the thoracic cavity while no portion of the esophagus presented within the abdominal cavity that documented the absence of the intra-abdominal portion in all studied dogs. The topographic anatomy, scanning electron and light microscopic examinations revealed that the gastroesophageal junction was located at the level of the phrenico-esophageal ligament (PEL) inside the esophageal hiatus. Our results were distinguished the morphology of the esophageal and gastric cardiac mucosa at the level of the gastroesophageal junction by the scanning electron micrographs. The light microscopical examination was explained the PEL attached to the esophageal side in one dog and to the gastric cardiac side in three dogs.

FHWA planning and environmental linkages annual report fiscal year 2011.

DOT National Transportation Integrated Search

2012-01-20

This report highlights the Federal Highway Administration's (FHWA) Planning and Environment Linkages (PEL) program activities for Fiscal Year 2011 (FY11). The PEL program's purpose is to provide transportation agencies with tools and resources to int...

A Framework for Evaluation of Climate Science Professional Development Projects: A NICE NASA Example

NASA Astrophysics Data System (ADS)

Comfort, K.; Bleicher, R. E.

2012-12-01

Purpose of Presentation This research presents the overall logic model for the evaluation plan for a three-year NASA-funded project focused on teacher professional development. This session will highlight how we are using data to continually revise the evaluation plan, and we will also share insights about communication between the external evaluator and the PI. Objectives and Research Questions PEL leverages three NASA NICE projects with a high school district, providing professional development for teachers, learning opportunities for students, parental involvement and interaction with NASA scientists. PEL aims to increase Climate Science literacy in high school students, with a focus on Hispanic students, through scientific argumentation using authentic NASA data. Our research will concentrate on investigating the following questions: 1. What do we know about the alternative conceptions students' hold about climate science and what is challenging for students? 2. Are students developing climate science literacy, especially in the difficult concept areas, after PEL implementation? 3. How effective is PEL in nurturing scientific argumentation skills? 4. How effective are the resources we are providing in PEL? 5. Is there evidence that teachers are establishing stronger leadership capacity in their schools? Theoretical Framework for PEL Evaluation The expectancy-value theory of achievement motivation (E-V-C) (Fan, 2011; Wigfield & Eccles, 1994) provides a theoretical foundation for the research. Expectancy is the degree to which a teacher or student has reason to expect that they will be successful in school. Value indicates whether they think that performance at school will be worthwhile to them. Cost is the perceived sacrifices that must be undertaken, or factors that can inhibit a successful performance at school. For students, data from an embedded E-V-C investigation will help articulate how E-V-C factors relate to student interest in science, continuing to study science, or embarking on STEM related careers. For teachers, the E-V-C measures will give insight into a key mediating variable on student achievement and interest in science. Analytic Strategy Data will be analyzed using a strategy developed by Huberman and Miles (2002). This methodology provides a framework for three research functions: 1) reducing the data to a subset of information without losing essential data, 2) displaying this information in a manner that facilitates discussion and notation of consensus upon emerging patterns, and 3) drawing and verifying conclusions. The multiple sources of qualitative and quantitative data allow for triangulation of findings, establishing a measure of validity and reliability to final findings and recommendations for future research. References Huberman, A. M., & Miles, M. B. (2002). The qualitative researcher's companion. Thousand Oaks, CA: Sage Publications. Wigfield, A., & Eccles, J.S. (2000). Expectancy-value theory of achievement motivation. Contemporary Educational Psychology, 25,68-81.

Final programmatic environmental impact statement for the uranium mill tailings remedial action ground water project. Volume I

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

None

1996-10-01

This programmatic environmental impact statement (PElS) was prepared for the Uranium Mill Tailings Remedial Action (UMTRA) Ground Water Project to comply with the National Environmental Policy Act (NEPA). This PElS provides an analysis of the potential impacts of the alternatives and ground water compliance strategies as well as potential cumulative impacts. On November 8, 1978, Congress enacted the Uranium Mill Tailings Radiation Control Act (UMTRCA) of 1978, Public Law, codified at 42 USC §7901 et seq. Congress found that uranium mill tailings " ... may pose a potential and significant radiation health hazard to the public, and that every reasonablemore » effort should be made to provide for stabilization, disposal, and control in a safe, and environmentally sound manner of such tailings in order to prevent or minimize other environmental hazards from such tailings." Congress authorized the Secretary of Energy to designate inactive uranium processing sites for remedial action by the U.S. Department of Energy (DOE). Congress also directed the U.S. Environmental Protection Agency (EPA) to set the standards to be followed by the DOE for this process of stabilization, disposal, and control. On January 5, 1983, EPA published standards (40 CFR Part 192) for the disposal and cleanup of residual radioactive materials. On September 3, 1985, the U.S. Court of Appeals for the Tenth Circuit set aside and remanded to EPA the ground water provisions of the standards. The EPA proposed new standards to replace remanded sections and changed other sections of 40 CFR Part 192. These proposed standards were published in the Federal Register on September 24, 1987 (52 FR 36000). Section 108 of the UMTRCA requires that DOE comply with EPA's proposed standards in the absence of final standards. The Ground Water Project was planned under the proposed standards. On January 11, 1995, EPA published the final rule, with which the DOE must now comply. The PElS and the Ground Water Project are in accordance with the final standards. The EPA reserves the right to modify the ground water standards, if necessary, based on changes in EPA drinking water standards. Appendix A contains a copy of the 1983 EPA ground water compliance standards, the 1987 proposed changes to the standards, and the 1995 final rule. Under UMTRA, DOE is responsible for bringing the designated processing sites into compliance with the EPA ground water standards and complying with all other applicable standards and requirements. The U.S. Nuclear Regulatory Commission (NRC) must concur with DOE's actions. States are full participants in the process. The DOE also must consult with any affected Indian tribes and the Bureau of Indian Affairs. Uranium processing activities at most of the inactive mill sites resulted in the contamination of ground water beneath and, in some cases, downgradient of the sites. This contaminated ground water often has elevated levels of constituents such as but not limited to uranium and nitrates. The purpose of the UMTRA Ground Water Project is to eliminate or reduce to acceptable levels the potential health and environmental consequences of milling activities by meeting the EPA ground water standards.« less

PehN, a Polygalacturonase Homologue with a Low Hydrolase Activity, Is Coregulated with the Other Erwinia chrysanthemi Polygalacturonases

PubMed Central

Hugouvieux-Cotte-Pattat, Nicole; Shevchik, Vladimir E.; Nasser, William

2002-01-01

Erwinia chrysanthemi 3937 secretes an arsenal of pectinolytic enzymes, including at least eight endo-pectate lyases encoded by pel genes, which play a major role in the soft-rot disease caused by this bacterium on various plants. E. chrysanthemi also produces some hydrolases that cleave pectin. Three adjacent hydrolase genes, pehV, pehW, and pehX, encoding exo-poly-α-d-galacturonosidases, have been characterized. These enzymes liberate digalacturonides from the nonreducing end of pectin. We report the identification of a novel gene, named pehN, encoding a protein homologous to the glycosyl hydrolases of family 28, which includes mainly polygalacturonases. PehN has a low hydrolase activity on polygalacturonate and on various pectins. PehN action favors the activity of the secreted endo-pectate lyases, mainly PelB and PelC, and that of the periplasmic exo-pectate lyase PelX. However, removal of the pehN gene does not significantly alter the virulence of E. chrysanthemi. Regulation of pehN transcription was analyzed by using gene fusions. Like other pectinase genes, pehN transcription is dependent on several environmental conditions. It is induced by pectic catabolic products and is affected by growth phase, catabolite repression, osmolarity, anaerobiosis, nitrogen starvation, and the presence of calcium ions. The transcription of pehN is modulated by the repressor KdgR, which controls almost all the steps of pectin catabolism, and by cyclic AMP receptor protein (CRP), the global activator of sugar catabolism. The regulator PecS, which represses the transcription of the pel genes but activates that of pehV, pehW, and pehX, also activates transcription of pehN. The three regulators KdgR, PecS, and CRP act by direct interaction with the pehN promoter region. The sequences involved in the binding of these three regulators and of RNA polymerase have been precisely defined. Analysis of the simultaneous binding of these proteins indicates that CRP and RNA polymerase bind cooperatively and that the binding of KdgR could prevent pehN transcription. In contrast, the activator effect of PecS is not linked to competition with KdgR or to cooperation with CRP or RNA polymerase. This effect probably results from competition between PecS and an unidentified repressor involved in peh regulation. PMID:11976295

Chemical and Ecological Health of White Sucker (Catostomus Commersoni) in Rock Creek Park, Washington, D.C., 2003-04

USGS Publications Warehouse

Miller, Cherie V.; Weyers, Holly S.; Blazer, Vicki; Freeman, Mary E.

2006-01-01

Several classes of chemicals that are known or suspected contaminants were found in bed sediment in Rock Creek, including polyaromatic hydrocarbons (PAHs), phthalate esters, organochlorine pesticides, dioxins and furans, trace metals and metalloids (mercury, arsenic, cadmium, chromium, cobalt, copper, lead, nickel, silver, and zinc), and polychlorinated biphenyls (total PCBs and selected aroclors). Concentrations of many of these chemicals consistently exceeded threshold or chronic-effects guidelines for the protection of aquatic life and often exceeded probable effects levels (PELs). Exceedance of PELs was dependent on the amount of total organic carbon in the sediments. Concurrent with the collection of sediment-quality data, white sucker (Catostomus commersoni) were evaluated for gross-external and internal-organ anomalies, whole-body burdens of chemical contaminants, and gut contents to determine prey. The histopathology of internal tissues of white sucker was compared to contaminant levels in fish tissue and bed sediment. Gut contents were examined to determine preferential prey and thus potential pathways for the bioaccumulation of chemicals from bed sediments. Male and female fish were tested separately. Lesions and other necroses were observed in all fish collected during both years of sample collection, indicating that fish in Rock Creek have experienced some form of environmental stress. No direct cause and effect was determined for chemical exposure and compromised fish health, but a substantial weight of evidence indicates that white sucker, which are bottom-feeding fish and low-order consumers in Rock Creek, are experiencing some reduction in vitality, possibly due to immunosuppression. Abnormalities observed in gonads of both sexes of white sucker and observations of abnormal behavior during spawning indicated some interruption in reproductive success.

Chemical and ecological health of white sucker (Catostomus Commersoni) in Rock Creek Park, Washington, D.C., 2003?04

USGS Publications Warehouse

Miller, C.V.; Weyers, H.S.; Blazer, V.S.; Freeman, M.E.

2006-01-01

Several classes of chemicals that are known or suspected contaminants were found in bed sediment in Rock Creek, including polyaromatic hydrocarbons (PAHs), phthalate esters, organochlorine pesticides, dioxins and furans, trace metals and metalloids (mercury, arsenic, cadmium, chromium, cobalt, copper, lead, nickel, silver, and zinc), and polychlorinated biphenyls (total PCBs and selected aroclors). Concentrations of many of these chemicals consistently exceeded thresholdor chronic-effects guidelines for the protection of aquatic life and often exceeded probable effects levels (PELs). Exceedance of PELs was dependent on the amount of total organic carbon in the sediments. Concurrent with the collection of sediment-quality data, white sucker (Catostomus commersoni) were evaluated for gross-external and internal-organ anomalies, whole-body burdens of chemical contaminants, and gut contents to determine prey. The histopathology of internal tissues of white sucker was compared to contaminant levels in fish tissue and bed sediment. Gut contents were examined to determine preferential prey and thus potential pathways for the bioaccumulation of chemicals from bed sediments. Male and female fish were tested separately. Lesions and other necroses were observed in all fish collected during both years of sample collection, indicating that fish in Rock Creek have experienced some form of environmental stress. No direct cause and effect was determined for chemical exposure and compromised fish health, but a substantial weight of evidence indicates that white sucker, which are bottom-feeding fish and low-order consumers in Rock Creek, are experiencing some reduction in vitality, possibly due to immunosuppression. Abnormalities observed in gonads of both sexes of white sucker and observations of abnormal behavior during spawning indicated some interruption in reproductive success.

Biofilm formation by Staphylococcus epidermidis on peritoneal dialysis catheters and the effects of extracellular products from Pseudomonas aeruginosa.

PubMed

Pihl, Maria; Arvidsson, Anna; Skepö, Marie; Nilsson, Martin; Givskov, Michael; Tolker-Nielsen, Tim; Svensäter, Gunnel; Davies, Julia R

2013-04-01

Biofilm formation by Staphylococcus epidermidis is a cause of infections related to peritoneal dialysis (PD). We have used a PD catheter flow-cell model in combination with confocal scanning laser microscopy and atomic force microscopy to study biofilm formation by S. epidermidis. Adherence to serum-coated catheters was four times greater than to uncoated ones, suggesting that S. epidermidis binds to serum proteins on the catheter surface. Pseudomonas aeruginosa biofilm supernatant interfered with the formation of a serum protein coat thereby reducing the capacity for biofilm formation in S. epidermidis. Supernatants from ΔpelA, ΔpslBCD and ΔrhlAB strains of P. aeruginosa showed no differences from the wild-type supernatant indicating that the effect on serum coat formation was not due to rhamnolipids or the PelA and PslBCD polysaccharides. Supernatant from P. aeruginosa also dispersed established S. epidermidis biofilms. Supernatants lacking PelA or PslBCD showed no differences from the wild type but that from a ΔrhlAB strain, showed reduced, but not abolished, capacity for dispersal. This suggests that rhamnolipids are involved but not wholly responsible for the effect. Thus, supernatants from P. aeruginosa contain promising substances for the prevention and treatment of biofilm infections, although further work is required to identity more active components. © 2013 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

PEL and Corridor Planning: State of the Practice Review of Planning and Environment Linkages Implementation in Corridor Planning

DOT National Transportation Integrated Search

2014-07-01

The Federal Highway Administration (FHWA) commissioned a review of transportation corridor plans to determine the extent to which these plans have utilized FHWA's Planning and Environment Linkages (PEL) approach, as described in the FHWA Guidance on ...

29 CFR 1910.1026 - Chromium (VI).

Code of Federal Regulations, 2011 CFR

2011-07-01

...) standard. (c) Permissible exposure limit (PEL). The employer shall ensure that no employee is exposed to an... not rotate employees to different jobs to achieve compliance with the PEL. (g) Respiratory protection...) occurs; or carry the products associated with these activities, or store such products in these areas. (j...

29 CFR 1910.1026 - Chromium (VI).

Code of Federal Regulations, 2010 CFR

2010-07-01

...) standard. (c) Permissible exposure limit (PEL). The employer shall ensure that no employee is exposed to an... not rotate employees to different jobs to achieve compliance with the PEL. (g) Respiratory protection...) occurs; or carry the products associated with these activities, or store such products in these areas. (j...

A Unique Case of Malignant Pleuropericardial Effusion: HHV-8-Unrelated PEL-Like Lymphoma—A Case Report and Review of the Literature

PubMed Central

Mohammad, Farhan; Siddique, Muhammad Neaman; Siddiqui, Faraz; Popalzai, M.; Asgari, Masoud; Odaimi, Marcel

2014-01-01

Primary effusion lymphoma (PEL) or body cavity lymphoma is a rare type of extra nodal lymphoma of B-cell origin that presents as lymphomatous effusion(s) without any nodal enlargement or tumor masses. It belongs to the group of AIDS related non-Hodgkin's lymphomas. First described in 1996 in HIV infected individuals who were coinfected with Kaposi's sarcoma-associated herpesvirus (KSHV) or HHV-8 virus, it was included as a separate entity in WHO classification of tumors of hematopoietic and lymphoid tissue in the year 2001. The definition included association with HHV-8 virus as a mandatory diagnostic criterion. However, cases were later reported where PEL-like disease process was diagnosed in HHV-8 negative patients. This was eventually recognized as a rare but distinct entity termed as “HHV-8-unrelated PEL-like lymphoma”. Herein, we are reporting a case of an elderly patient who presented with a large pleuropericardial effusion and was eventually diagnosed with this entity. Till date, only around 50 cases of HHV-8-unrelated PEL-like lymphoma have been reported and our case being EBV, HIV, and Hepatitis C negative makes it very unique and rare occurrence. We are also presenting a review of relevant literature focused mainly on comparing outcomes in patients treated with and without chemotherapy. PMID:24716045

Temporal disconnectivity of the energy landscape in glassy systems

NASA Astrophysics Data System (ADS)

Lempesis, Nikolaos; Boulougouris, Georgios C.; Theodorou, Doros N.

2013-03-01

An alternative graphical representation of the potential energy landscape (PEL) has been developed and applied to a binary Lennard-Jones glassy system, providing insight into the unique topology of the system's potential energy hypersurface. With the help of this representation one is able to monitor the different explored basins of the PEL, as well as how - and mainly when - subsets of basins communicate with each other via transitions in such a way that details of the prior temporal history have been erased, i.e., local equilibration between the basins in each subset has been achieved. In this way, apart from detailed information about the structure of the PEL, the system's temporal evolution on the PEL is described. In order to gather all necessary information about the identities of two or more basins that are connected with each other, we consider two different approaches. The first one is based on consideration of the time needed for two basins to mutually equilibrate their populations according to the transition rate between them, in the absence of any effect induced by the rest of the landscape. The second approach is based on an analytical solution of the master equation that explicitly takes into account the entire explored landscape. It is shown that both approaches lead to the same result concerning the topology of the PEL and dynamical evolution on it. Moreover, a "temporal disconnectivity graph" is introduced to represent a lumped system stemming from the initial one. The lumped system is obtained via a specially designed algorithm [N. Lempesis, D. G. Tsalikis, G. C. Boulougouris, and D. N. Theodorou, J. Chem. Phys. 135, 204507 (2011), 10.1063/1.3663207]. The temporal disconnectivity graph provides useful information about both the lumped and the initial systems, including the definition of "metabasins" as collections of basins that communicate with each other via transitions that are fast relative to the observation time. Finally, the two examined approaches are compared to an "on the fly" molecular dynamics-based algorithm [D. G. Tsalikis, N. Lempesis, G. C. Boulougouris, and D. N. Theodorou, J. Chem. Theory Comput. 6, 1307 (2010), 10.1021/ct9004245].

A colorimetric sensor array of porous pigments.

PubMed

Lim, Sung H; Kemling, Jonathan W; Feng, Liang; Suslick, Kenneth S

2009-12-01

The development of a low-cost, simple colorimetric sensor array capable of the detection and identification of toxic gases is reported. This technology uses a disposable printed array of porous pigments in which metalloporphyrins and chemically-responsive dyes are immobilized in a porous matrix of organically modified siloxanes (ormosils) and printed on a porous membrane. The printing of the ormosil into the membrane is highly uniform and does not lessen the porosity of the membrane, as shown by scanning electron microscopy. When exposed to an analyte, these pigments undergo reactions that result in well-defined color changes due to strong chemical interactions: ligation to metal ions, Lewis or Brønsted acid-base interactions, hydrogen bonding, etc. Striking visual identification of 3 toxic gases has been shown at the IDLH (immediately dangerous to life and health) concentration, at the PEL (permissible exposure level), and at a level well below the PEL. Identification and quantification of analytes were achieved using the color change profiles, which were readily distinguishable in a hierarchical clustering analysis (HCA) dendrogram, with no misclassifications in 50 trials.

A colorimetric sensor array of porous pigments

PubMed Central

Lim, Sung H.; Kemling, Jonathan W.; Feng, Liang

2010-01-01

The development of a low-cost, simple colorimetric sensor array capable of detection and identification of toxic gases is reported. This technology uses a disposable printed array of porous pigments in which metalloporphyrins and chemically responsive dyes are immobilized in a porous matrix of organically modified siloxanes (ormosils) and printed on a porous membrane. The printing of the ormosil into the membrane is highly uniform and does not lessen the porosity of the membrane, as shown by scanning electron microscopy. When exposed to an analyte, these pigments undergo reactions that result in well-defined color changes due to strong chemical interactions: ligation to metal ions, Lewis or Bronsted acid-base interactions, hydrogen bonding, etc. Striking visual identification of 3 toxic gases has been shown at the IDLH (immediately dangerous to life and health), at the PEL (permissible exposure level), and at a level well below the PEL. Identification and quantification of analytes were achieved using the color change profiles, which were readily distinguishable in a hierarchical clustering analysis (HCA) dendrogram, with no misclassifications in 50 trials. PMID:19918616

Radio frequency radiation exposure of the F-15 crewmember.

PubMed

Laughrey, Michael S; Grayson, J Kevin; Jauchem, James R; Misener, Andrea E

2003-08-01

In the United States Air Force, pilots of F-15 fighter aircraft use fire control radars to search for enemy targets and to launch beyond visual range radar missiles. The fire control radars must be of a sufficient power output to enable a target return, but pilots are concerned about deleterious health effects from the levels of radio frequency radiation (RFR) they are exposed to. Measurement of RFR while actually in flight in the F-15 has never been performed. This study was designed to document the RFR levels that pilots are exposed to on normal missions while in flight with the radar on and active. A hand-held meter was used to measure electromagnetic fields during three F-15 flights. Instrumentation consisted of a Narda Microwave Model 8718 digital survey meter and Model 8723 broadband isotropic E-field probe with a frequency range between 300 MHz and 50 GHz. The measurements were conducted in the rear cockpit of an F-15D aircraft. Three missions were flown representing the standard missions an F-15 pilot flies on an everyday basis. The missions were: night intercepts, offensive basic fighter maneuvers, and defensive basic fighter maneuvers. Based on the data collected during three F-15 missions, all recorded RFR exposure to the crewmember in the F-15 was within the OSHA Permissible Exposure Limit (PEL) of 10 mW x cm(-2). Based on a limited sample, RFR exposures in F-15 cockpits appear to be well below the PEL.

Ototoxic occupational exposures for a stock car racing team: II. chemical surveys.

PubMed

Gwin, Kristin K; Wallingford, Kenneth M; Morata, Thais C; Van Campen, Luann E; Dallaire, Jacques; Alvarez, Frank J

2005-08-01

The National Institute for Occupational Safety and Health (NIOSH) conducted a series of surveys to evaluate occupational exposure to noise and potentially ototoxic chemical agents among members of a professional stock car racing team. Exposure assessments included site visits to the team's race shop and a worst-case scenario racetrack. During site visits to the race team's shop, area samples were collected to measure exposures to potentially ototoxic chemicals, including, organic compounds (typical of solvents), metals, and carbon monoxide (CO). Exposures to these chemicals were all below their corresponding Occupational Safety and Health Administration (OSHA) permissible exposure limits (PELs), NIOSH recommended exposure limits (RELs), and American Conference of Governmental Industrial Hygienists (ACGIH) threshold limit values (TLVs). During site visits to the racetrack, area and personal samples were collected for organic compounds, lead, and CO in and around the "pit" area where the cars undergo race preparation and service during the race. Exposures to organic compounds and lead were either nondetectable or too low to quantify. Twenty-five percent of the CO time-weighted average concentrations exceeded the OSHA PEL, NIOSH REL, and ACGIH TLV after being adjusted for a 10-hour workday. Peak CO measurements exceeded the NIOSH recommended ceiling limit of 200 ppm. Based on these data, exposures to potentially ototoxic chemicals are probably not high enough to produce an adverse effect greater than that produced by the high sound pressure levels alone. However, carbon monoxide levels occasionally exceeded all evaluation criteria at the racetrack.

Sustained-release solid dispersion of pelubiprofen using the blended mixture of aminoclay and pH independent polymers: preparation and in vitro/in vivo characterization.

PubMed

Lee, Yeo-Song; Song, Jae Guen; Lee, Sang Hoon; Han, Hyo-Kyung

2017-11-01

The present study aimed to develop the sustained-release oral dosage form of pelubiprofen (PEL) by using the blended mixture of 3-aminopropyl functionalized-magnesium phyllosilicate (aminoclay) and pH-independent polymers. The sustained-release solid dispersion (SRSD) was prepared by the solvent evaporation method and the optimal composition of SRSD was determined as the weight ratio of drug: Eudragit® RL PO: Eudragit® RS PO of 1:1:2 in the presence of 1% of aminoclay (SRSD(F6)). The dissolution profiles of SRSD(F6) were examined at different pHs and in the simulated intestinal fluids. The drug release from SRSD(F6) was limited at pH 1.2 and gradually increased at pH 6.8, resulting in the best fit to Higuchi equation. The sustained drug release from SRSD(F6) was also maintained in simulated intestinal fluid at fasted-state (FaSSIF) and fed-state (FeSSIF). The structural characteristics of SRSD(F6) were examined by using powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FT-IR), indicating the change of drug crystallinity to an amorphous form. After oral administration in rats, SRSD(F6) exhibited the prolonged drug exposure in plasma. For both PEL and PEL-transOH (active metabolite), once a day dosing of SRSD(F6) achieved oral exposure (AUC) comparable to those from the multiple dosing (3 times a day) of untreated drug. In addition, the in vivo absorption of SRSD(F6) was well-correlated with the in vitro dissolution data, establishing a good level A in vitro/in vivo correlation. These results suggest that SRSD(F6) should be promising for the sustained-release of PEL, thereby reducing the dosing frequency.

A Rice PECTATE LYASE-LIKE Gene Is Required for Plant Growth and Leaf Senescence1[OPEN

PubMed Central

Leng, Yujia; Yang, Yaolong; Ren, Deyong; Dai, Liping; Wang, Yuqiong; Chen, Long; Tu, Zhengjun; Gao, Yihong; Zhu, Li; Hu, Jiang; Gao, Zhenyu; Guo, Longbiao; Lin, Yongjun

2017-01-01

To better understand the molecular mechanisms behind plant growth and leaf senescence in monocot plants, we identified a mutant exhibiting dwarfism and an early-senescence leaf phenotype, termed dwarf and early-senescence leaf1 (del1). Histological analysis showed that the abnormal growth was caused by a reduction in cell number. Further investigation revealed that the decline in cell number in del1 was affected by the cell cycle. Physiological analysis, transmission electron microscopy, and TUNEL assays showed that leaf senescence was triggered by the accumulation of reactive oxygen species. The DEL1 gene was cloned using a map-based approach. It was shown to encode a pectate lyase (PEL) precursor that contains a PelC domain. DEL1 contains all the conserved residues of PEL and has strong similarity with plant PelC. DEL1 is expressed in all tissues but predominantly in elongating tissues. Functional analysis revealed that mutation of DEL1 decreased the total PEL enzymatic activity, increased the degree of methylesterified homogalacturonan, and altered the cell wall composition and structure. In addition, transcriptome assay revealed that a set of cell wall function- and senescence-related gene expression was altered in del1 plants. Our research indicates that DEL1 is involved in both the maintenance of normal cell division and the induction of leaf senescence. These findings reveal a new molecular mechanism for plant growth and leaf senescence mediated by PECTATE LYASE-LIKE genes. PMID:28455404

A Rice PECTATE LYASE-LIKE Gene Is Required for Plant Growth and Leaf Senescence.

PubMed

Leng, Yujia; Yang, Yaolong; Ren, Deyong; Huang, Lichao; Dai, Liping; Wang, Yuqiong; Chen, Long; Tu, Zhengjun; Gao, Yihong; Li, Xueyong; Zhu, Li; Hu, Jiang; Zhang, Guangheng; Gao, Zhenyu; Guo, Longbiao; Kong, Zhaosheng; Lin, Yongjun; Qian, Qian; Zeng, Dali

2017-06-01

To better understand the molecular mechanisms behind plant growth and leaf senescence in monocot plants, we identified a mutant exhibiting dwarfism and an early-senescence leaf phenotype, termed dwarf and early-senescence leaf1 ( del1 ). Histological analysis showed that the abnormal growth was caused by a reduction in cell number. Further investigation revealed that the decline in cell number in del1 was affected by the cell cycle. Physiological analysis, transmission electron microscopy, and TUNEL assays showed that leaf senescence was triggered by the accumulation of reactive oxygen species. The DEL1 gene was cloned using a map-based approach. It was shown to encode a pectate lyase (PEL) precursor that contains a PelC domain. DEL1 contains all the conserved residues of PEL and has strong similarity with plant PelC. DEL1 is expressed in all tissues but predominantly in elongating tissues. Functional analysis revealed that mutation of DEL1 decreased the total PEL enzymatic activity, increased the degree of methylesterified homogalacturonan, and altered the cell wall composition and structure. In addition, transcriptome assay revealed that a set of cell wall function- and senescence-related gene expression was altered in del1 plants. Our research indicates that DEL1 is involved in both the maintenance of normal cell division and the induction of leaf senescence. These findings reveal a new molecular mechanism for plant growth and leaf senescence mediated by PECTATE LYASE-LIKE genes. © 2017 American Society of Plant Biologists. All Rights Reserved.

Addition of genes for cellobiase and pectinolytic activity in Escherichia coli for fuel ethanol production from pectin-rich lignocellulosic biomass.

PubMed

Edwards, Meredith C; Henriksen, Emily Decrescenzo; Yomano, Lorraine P; Gardner, Brian C; Sharma, Lekh N; Ingram, Lonnie O; Doran Peterson, Joy

2011-08-01

Ethanologenic Escherichia coli strain KO11 was sequentially engineered to contain the Klebsiella oxytoca cellobiose phosphotransferase genes (casAB) as well as a pectate lyase (pelE) from Erwinia chrysanthemi, yielding strains LY40A (casAB) and JP07 (casAB pelE), respectively. To obtain an effective secretion of PelE, the Sec-dependent pathway out genes from E. chrysanthemi were provided on a cosmid to strain JP07 to construct strain JP07C. Finally, oligogalacturonide lyase (ogl) from E. chrysanthemi was added to produce strain JP08C. E. coli strains LY40A, JP07, JP07C, and JP08C possessed significant cellobiase activity in cell lysates, while only strains JP07C and JP08C demonstrated extracellular pectate lyase activity. Fermentations conducted by using a mixture of pure sugars representative of the composition of sugar beet pulp (SBP) showed that strains LY40A, JP07, JP07C, and JP08C were able to ferment cellobiose, resulting in increased ethanol production from 15 to 45% in comparison to that of KO11. Fermentations with SBP at very low fungal enzyme loads during saccharification revealed significantly higher levels of ethanol production for LY40A, JP07C, and JP08C than for KO11. JP07C ethanol yields were not considerably higher than those of LY40A; however, oligogalacturonide polymerization studies showed an increased breakdown of biomass to small-chain (degree of polymerization, ≤6) oligogalacturonides. JP08C achieved a further breakdown of polygalacturonate to monomeric sugars, resulting in a 164% increase in ethanol yields compared to those of KO11. The addition of commercial pectin methylesterase (PME) further increased JP08C ethanol production compared to that of LY40A by demethylating the pectin for enzymatic attack by pectin-degrading enzymes.

Addition of Genes for Cellobiase and Pectinolytic Activity in Escherichia coli for Fuel Ethanol Production from Pectin-Rich Lignocellulosic Biomass▿

PubMed Central

Edwards, Meredith C.; Henriksen, Emily DeCrescenzo; Yomano, Lorraine P.; Gardner, Brian C.; Sharma, Lekh N.; Ingram, Lonnie O.; Doran Peterson, Joy

2011-01-01

Ethanologenic Escherichia coli strain KO11 was sequentially engineered to contain the Klebsiella oxytoca cellobiose phosphotransferase genes (casAB) as well as a pectate lyase (pelE) from Erwinia chrysanthemi, yielding strains LY40A (casAB) and JP07 (casAB pelE), respectively. To obtain an effective secretion of PelE, the Sec-dependent pathway out genes from E. chrysanthemi were provided on a cosmid to strain JP07 to construct strain JP07C. Finally, oligogalacturonide lyase (ogl) from E. chrysanthemi was added to produce strain JP08C. E. coli strains LY40A, JP07, JP07C, and JP08C possessed significant cellobiase activity in cell lysates, while only strains JP07C and JP08C demonstrated extracellular pectate lyase activity. Fermentations conducted by using a mixture of pure sugars representative of the composition of sugar beet pulp (SBP) showed that strains LY40A, JP07, JP07C, and JP08C were able to ferment cellobiose, resulting in increased ethanol production from 15 to 45% in comparison to that of KO11. Fermentations with SBP at very low fungal enzyme loads during saccharification revealed significantly higher levels of ethanol production for LY40A, JP07C, and JP08C than for KO11. JP07C ethanol yields were not considerably higher than those of LY40A; however, oligogalacturonide polymerization studies showed an increased breakdown of biomass to small-chain (degree of polymerization, ≤6) oligogalacturonides. JP08C achieved a further breakdown of polygalacturonate to monomeric sugars, resulting in a 164% increase in ethanol yields compared to those of KO11. The addition of commercial pectin methylesterase (PME) further increased JP08C ethanol production compared to that of LY40A by demethylating the pectin for enzymatic attack by pectin-degrading enzymes. PMID:21666025

PELS: A Noble Architecture and Framework for a Personal E-Learning System (PELS)

ERIC Educational Resources Information Center

Dewan, Jahangir; Chowdhury, Morshed; Batten, Lynn

2014-01-01

This article presents a personal e-learning system architecture in the context of a social network environment. The main objective of a personal e-learning system is to develop individual skills on a specific subject and share resources with peers. The authors' system architecture defines the organisation and management of a personal learning…

Some aspects of adaptive transform coding of multispectral data

NASA Technical Reports Server (NTRS)

Ahmed, N.; Natarajan, T.

1977-01-01

This paper concerns a data compression study pertaining to multi-spectral scanner (MSS) data. The motivation for this undertaking is the need for securing data compression of images obtained in connection with the Landsat Follow-On Mission, where a compression of at least 6:1 is required. The MSS data used in this study consisted of four scenes: Tristate, consisting of 256 pels per row and a total of 512 rows - i.e., (256x512), (2) Sacramento (256x512), (3) Portland (256x512), and (4) Bald Knob (200x256). All these scenes were on digital tape at 6 bits/pel. The corresponding reconstructed scenes of 1 bit/pel (i.e., a 6:1 compression) are included.

An eco-friendly direct spectrofluorimetric method for the determination of irreversible tyrosine kinase inhibitors, neratinib and pelitinib: application to stability studies.

PubMed

Maher, H M; Alzoman, N Z; Shehata, S M

2017-03-01

A new rapid and simple stability-indicating spectrofluorimetric method has been developed for the determination of two irreversible tyrosine kinase inhibitors (TKIs), neratinib (NER) and pelitinib (PEL). The method is based upon measurement of the native fluorescence intensity of both drugs at λ ex 270 nm in aqueous borate buffer solutions (pH 10.5). The fluorescence intensity recorded at 545 nm (NER) and 465 nm (PEL) were rectilinear over the concentration range of 0.1-10 μg/mL for both drugs with a high correlation coefficient (r > 0.999). The proposed method provided low limits of detection and of quantitation of 0.07, 0.11 μg/mL (NER) and 0.02, 0.05 μg/mL (PEL), respectively. The method was successfully applied for the determination of NER and PEL in bulk powder. The proposed methods were fully validated as per the International Conference on Harmonisation (ICH) guidelines. The application of the method was extended to stability studies of both NER and PEL under different forced-degradation conditions (acidic-induced, base-induced, oxidative, wet heat, and photolytic degradation). Moreover, the kinetics of the base-induced and oxidative degradation of both drugs was investigated and the pseudo-first-order rate constants and half-lives were estimated at different temperatures. Also, an Arrhenius plot was applied to predict the stability behaviour of the two drugs at room temperature. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Molecular variability and evolution of the pectate lyase (pel-2) parasitism gene in cyst nematodes parasitizing different solanaceous plants.

PubMed

Geric Stare, Barbara; Fouville, Didier; Širca, Saša; Gallot, Aurore; Urek, Gregor; Grenier, Eric

2011-02-01

While pectate lyases are major parasitism factors in plant-parasitic nematodes, there is little information on the variability of these genes within species and their utility as pathotype or host range molecular markers. We have analysed polymorphisms of pectate lyase 2 (pel-2) gene, which degrades the unesterified polygalacturonate (pectate) of the host cell-wall, in the genus Globodera. Molecular variability of the pel-2 gene and the predicted protein was evaluated in populations of G. rostochiensis, G. pallida, G. "mexicana" and G. tabacum. Seventy eight pel-2 sequences were obtained and aligned. Point mutations were observed at 373 positions, 57% of these affect the coding part of the gene and produce 129 aa replacements. The observed polymorphism does not correlate either to the pathotypes proposed in potato cyst nematodes (PCN) or the subspecies described in tobacco cyst nematodes. The trees reveal a topology different from the admitted species topology as G. rostochiensis and G. pallida sequences are more similar to each other than to G. tabacum. Species-specific sites, potentially applicable for identification, and sites distinguishing PCN from tobacco cyst nematodes, were identified. As both G. rostochiensis and G. pallida display the same host range, but distinct from G. tabacum, which cannot parasitize potato plants, it is tempting to speculate that pel-2 genes polymorphism may be implicated in this adaptation, a view supported by the fact that no active pectate lyase 2 was found in G. "mexicana", a close relative of G. pallida that is unable to develop on cultivated potato varieties.

A Comprehensive PEL-IEP Speech Curriculum Overview and Related Carryover and Summary Forms Designed for Speech Therapy Services for the Hearing-Impaired.

ERIC Educational Resources Information Center

Erlbaum, Sheila Judith

1990-01-01

This article presents a curriculum for speech-language-communication skills which combines the Present Education Level and Individualized Education Program formats for deaf and hearing-impaired students. Information on carryover procedures, parent/teacher contact, and report card format is presented. The curriculum was designed for preschool…

Stringency of workplace air contaminant exposure limits: a case study of OSHA risk management.

PubMed

Hakes, J K

1999-12-01

Political context may play a large role in influencing the efficiency of environmental and health regulations. This case study uses data from a 1989 update of the Occupational Safety and Health Administration (OSHA) Permissible Exposure Limits (PELs) program to determine the relative effects of legislative mandates, costly acquisition of information by the agency, and pressure applied by special interest groups upon exposure standards. The empirical analysis suggests that federal agencies successfully thwart legislative attempts to limit agency discretion, and that agencies exercise bounded rationality by placing greater emphasis on more easily obtained information. The 1989 PELs were less significantly related to more costly information, contained "safety factors" for chemicals presenting relatively more ambiguous risks, and the proposed standard stringencies showed evidence of being influenced by vying industry and labor interests.

Pre-EDIT: protocol for a randomised feasibility trial of elastance-directed intrapleural catheter or talc pleurodesis (EDIT) in malignant pleural effusion

PubMed Central

Martin, Geoffrey A; Tsim, Selina; Kidd, Andrew C; Foster, John E; McLoone, Philip; Chalmers, Anthony

2018-01-01

Introduction Non-expansile lung (NEL) is a common cause of talc pleurodesis (TP) failure in malignant pleural effusion (MPE), but is often occult prior to drainage. Reliable detection of NEL would allow patients to be allocated between intrapleural catheter (IPC) and TP. High pleural elastance (PEL) has been associated with NEL in observational studies. Pre-EDIT is a randomised feasibility trial of elastance-directed IPC or TP (EDIT) management using a novel, purpose-built digital pleural manometer (Rocket Medical, UK). Methods and analysis Consecutive patients with MPE without prior evidence of NEL or preference for IPC will be randomised 1:1 between EDIT management and standard care (an attempt at TP). The primary objective is to determine whether sufficient numbers of patients (defined as 30 within 12 months (or 15 over 6 months)) can be recruited and randomised to justify a subsequent phase III trial testing the efficacy of EDIT management. Secondary objectives include safety, technical feasibility and validation of study design elements, including the definition of PEL using 4D pleural MRI before and after fluid aspiration. EDIT involves PEL assessment during a large volume pleural fluid aspiration, followed by an attempt at TP or placement of an IPC within 24 hours. Patients will be allocated to IPC if the rolling average PEL sustained over at least 250 mL fluid aspirated (PEL250) is ≥ 14.5 cm H2O/L. Ethics and dissemination Pre-EDIT was approved by the West of Scotland Regional Ethics Committee on 8 March 2017 (Ref: 17/WS/0042). Results will be presented at scientific meetings and published in peer-reviewed journals. Trial registration number NCT03319186; Pre-results. PMID:29862030

Characterization of the potential energy landscape of an antiplasticized polymer.

PubMed

Riggleman, Robert A; Douglas, Jack F; de Pablo, Juan J

2007-07-01

The nature of the individual transitions on the potential energy landscape (PEL) associated with particle motion are directly examined for model fragile glass-forming polymer melts, and the results are compared to those of an antiplasticized polymer system. In previous work, we established that the addition of antiplasticizer reduces the fragility of glass formation so that the antiplasticized material is a stronger glass former. In the present work, we find that the antiplasticizing molecules reduce the energy barriers for relaxation compared to the pure polymer, implying that the antiplasticized system has smaller barriers to overcome in order to explore its configuration space. We examine the cooperativity of segmental motion in these bulk fluids and find that more extensive stringlike collective motion enables the system to overcome larger potential energy barriers, in qualitative agreement with both the Stillinger-Weber and Adam-Gibbs views of glass formation. Notably, the stringlike collective motion identified by our PEL analysis corresponds to incremental displacements that occur within larger-scale stringlike particle displacement processes associated with PEL metabasin transitions that mediate structural relaxation. These "substrings" nonetheless seem to exhibit changes in relative size with antiplasticization similar to those observed in "superstrings" that arise at elevated temperatures. We also study the effects of confinement on the energy barriers in each system. Film confinement makes the energy barriers substantially smaller in the pure polymer, while it has little effect on the energy barriers in the antiplasticized system. This observation is qualitatively consistent with our previous studies of stringlike motion in these fluids at higher temperatures and with recent experimental measurements by Torkelson and co-workers.

Risk of Adverse Health and Performance Effects of Celestial Dust Exposure

NASA Technical Reports Server (NTRS)

Scully, Robert R.; Meyers, Valerie E.

2015-01-01

Crew members can be directly exposed to celestial dust in several ways. After crew members perform extravehicular activities (EVAs), they may introduce into the habitat dust that will have collected on spacesuits and boots. Cleaning of the suits between EVAs and changing of the Environmental Control Life Support System filters are other operations that could result in direct exposure to celestial dusts. In addition, if the spacesuits used in exploration missions abrade the skin, as current EVA suits have, then contact with these wounds would provide a source of exposure. Further, if celestial dusts gain access to a suit's interior, as was the case during the Apollo missions, the dust could serve as an additional source of abrasions or enhance suit-induced injuries. When a crew leaves the surface of a celestial body and returns to microgravity, the dust that is introduced into the return vehicle will "float," thus increasing the opportunity for ocular and respiratory injury. Because the features of the respirable fraction of lunar dusts indicate they could be toxic to humans, NASA conducted several studies utilizing lunar dust simulants and authentic lunar dust to determine the unique properties of lunar dust that affect physiology, assess the dermal and ocular irritancy of the dust, and establish a permissible exposure limit for episodic exposure to airborne lunar dust during missions that would involve no more than 6 months stay on the lunar surface. Studies, with authentic lunar soils from both highland (Apollo 16) and mare (Apollo17) regions demonstrated that the lunar soil is highly abrasive to a high fidelity model of human skin. Studies of lunar dust returned during the Apollo 14 mission from an area of the moon in which the soils were comprised of mineral constituents from both major geological regions (highlands and mares regions) demonstrated only minimal ocular irritancy, and pulmonary toxicity that was less than the highly toxic terrestrial crystalline silica (Permissible Exposure Limit [PEL] 0.05 mg/m3) but more toxic than the nuisance dust titanium dioxide (TiO2 [PEL 5.0 mg/m3]). A PEL for episodic exposure to airborne lunar dust during a six-month stay on the lunar surface was established, in consultation with an independent, extramural panel of expert pulmonary toxicologists, at 0.3 mg/m3. The PEL provided for lunar dust is limited to the conditions and exposure specified therefore additional research remains to be accomplished with lunar dust to further address the issues of activation, address other areas of more unique lunar geology (Glotch et al., 2010; Greenhagen et al., 2010), examine potential toxicological effects of inhaled or ingested dust upon other organ systems, such cardiovascular, nervous systems, and examine effects of acute exposure to massive doses of dust such as may occur during off-nominal situations. Work to support the establishment of PELs for Martian dust and dusts of asteroids remains to be accomplished. The literature that describes health effects of exposure to toxic terrestrial dusts provides substantial basis for concern that prolonged exposure to respirable celestial dust could be detrimental to human health. Celestial bodies where a substantial portion of the dust is in the respirable range or where the dusts have large reactive surface areas or contain transition metals or volatile organics, represent greater risks of adverse effects from exposure to the dust. It is possible that in addition to adverse effects to the respiratory system, inhalation and ingestion of celestial dusts could pose risks to other systems

Sampling and Analysis Issues Relating to the ACGIH Notice of Intended Change for the Beryllium Threshold Limit Value

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

Brisson, Michael J.; Ashley, Kevin

2005-08-16

Beryllium in various forms is widely used throughout the world in ceramics, aerospace and military applications, electronics, and sports equipment. Workplace exposure to beryllium is a growing industrial hygiene concern due to the potential for development of chronic beryllium disease (CBD), a lung condition with no known cure, in a small percentage of those exposed. There are workplace exposure limits for beryllium that have been in place for several decades. However, recent studies suggest that the current American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV) and the Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (PEL)more » may not be sufficiently protective for workers who are potentially exposed to airborne beryllium. Early in 2005, ACGIH issued a Notice of Intended Change (NIC) to the current TLV for beryllium which entails a 100-fold reduction (from 2 to 0.02 micrograms per cubic meter of sampled air). It is noted that ACGIH TLVs do not carry legal force in the manner that OSHA PELs or other federal regulations do. Nevertheless, OSHA plans a beryllium rulemaking in the near future, and a reduction in the PEL is anticipated. Also, if this change in the TLV for beryllium is adopted, it is reasonable to assume that at least some sampling and analysis activities will need to be modified to address airborne beryllium at the lower levels. There are implications to both the industrial hygiene and the laboratory communities, which are discussed.« less

Dynamic remodeling of microbial biofilms by functionally distinct exopolysaccharides.

PubMed

Chew, Su Chuen; Kundukad, Binu; Seviour, Thomas; van der Maarel, Johan R C; Yang, Liang; Rice, Scott A; Doyle, Patrick; Kjelleberg, Staffan

2014-08-05

Biofilms are densely populated communities of microbial cells protected and held together by a matrix of extracellular polymeric substances. The structure and rheological properties of the matrix at the microscale influence the retention and transport of molecules and cells in the biofilm, thereby dictating population and community behavior. Despite its importance, quantitative descriptions of the matrix microstructure and microrheology are limited. Here, particle-tracking microrheology in combination with genetic approaches was used to spatially and temporally study the rheological contributions of the major exopolysaccharides Pel and Psl in Pseudomonas aeruginosa biofilms. Psl increased the elasticity and effective cross-linking within the matrix, which strengthened its scaffold and appeared to facilitate the formation of microcolonies. Conversely, Pel reduced effective cross-linking within the matrix. Without Psl, the matrix becomes more viscous, which facilitates biofilm spreading. The wild-type biofilm decreased in effective cross-linking over time, which would be advantageous for the spreading and colonization of new surfaces. This suggests that there are regulatory mechanisms to control production of the exopolysaccharides that serve to remodel the matrix of developing biofilms. The exopolysaccharides were also found to have profound effects on the spatial organization and integration of P. aeruginosa in a mixed-species biofilm model of P. aeruginosa-Staphylococcus aureus. Pel was required for close association of the two species in mixed-species microcolonies. In contrast, Psl was important for P. aeruginosa to form single-species biofilms on top of S. aureus biofilms. Our results demonstrate that Pel and Psl have distinct physical properties and functional roles during biofilm formation. Importance: Most bacteria grow as biofilms in the environment or in association with eukaryotic hosts. Removal of biofilms that form on surfaces is a challenge in clinical and industrial settings. One of the defining features of a biofilm is its extracellular matrix. The matrix has a heterogeneous structure and is formed from a secretion of various biopolymers, including proteins, extracellular DNA, and polysaccharides. It is generally known to interact with biofilm cells, thus affecting cell physiology and cell-cell communication. Despite the fact that the matrix may comprise up to 90% of the biofilm dry weight, how the matrix properties affect biofilm structure, maturation, and interspecies interactions remain largely unexplored. This study reveals that bacteria can use specific extracellular polymers to modulate the physical properties of their microenvironment. This in turn impacts biofilm structure, differentiation, and interspecies interactions. Copyright © 2014 Chew et al.

Nuclear Drug Delivery for Breast Cancer Chemotherapy

DTIC Science & Technology

2008-09-01

similar results were obtained. 10.;)UI:SJI:IJI Il:l1lVl;) Polymer -drug conjugate, nuclear drug delivery, drug resistance, breast cancer 10...conjugates (5 Months): a. Synthesize linear polyethyleneimine (pEl, Mn ~5-10kDa) by ring-opening polymerization . b. React the PEl with proper 5-membered...functionalized CR-PEI. Milestone 1: Obtaining the FA- or LHRH-functionalized TCRC with optimal charge-reversal kinetics. TASK 2. To in vitro and in vivo evaluate

Colorimetric sensor array for determination and identification of toxic industrial chemicals.

PubMed

Feng, Liang; Musto, Christopher J; Kemling, Jonathan W; Lim, Sung H; Zhong, Wenxuan; Suslick, Kenneth S

2010-11-15

A low-cost yet highly sensitive colorimetric sensor array for the detection and identification of toxic industrial chemicals (TICs) has been developed. The sensor consists of a disposable array of cross-responsive nanoporous pigments whose colors are changed by diverse chemical interactions with analytes. Clear differentiation among 20 different TICs has been easily achieved at both their IDLH (immediately dangerous to life or health) concentration within 2 min of exposure and PEL (permissible exposure limit) concentration within 5 min of exposure with no errors or misclassifications. Detection limits are generally well below the PEL (in most cases below 5% of PEL) and are typically in the low ppb range. The colorimetric sensor array is not responsive to changes in humidity or temperature over a substantial range. The printed arrays show excellent batch to batch reproducibility and long shelf life (greater than 3 months).

2,4,6-Trinitrotoluene (TNT) air concentrations, hemoglobin changes, and anemia cases in respirator protected TNT munitions demilitarization workers.

PubMed

Bradley, Melville D

2011-03-01

2,4,6-Trinitrotoluene (TNT) is an explosive used in munitions production that is known to cause both aplastic and hemolytic anemia in exposed workers. Anemia in a TNT worker is considered a sentinel health event (occupational) (SHE(O)) in the United States (US). Deaths have been reported secondary to aplastic anemia. Studies have shown that TNT systemic absorption is significant by both the respiratory and dermal routes. No studies encountered looked at hemoglobin change or anemia cases in respiratory protected workers. It is hypothesized that respiratory protection is insufficient to protect TNT workers from the risk of anemia development and hemoglobin concentration drop. A records review of eight groups of respiratory protected TNT workers' pre-exposure hemoglobin levels were compared with their during-exposure hemoglobin levels for statistically significant (alpha level 0.05) hemoglobin level changes, and anemia cases were recorded. A curve estimation analysis was performed between mean TNT air concentrations and mean hemoglobin change values. Statistically significant hemoglobin level drops and anemia cases were apparent at TNT air concentrations about the REL and PEL in respiratory protected workers. There were no anemia cases or statistically significant hemoglobin level drops at concentrations about the TLV, however. A statistically significant inverse non-linear regression model was found to be the best fit for regressing hemoglobin change on TNT air concentration. Respiratory protection may be inadequate to prevent workers who are at risk for TNT skin absorption from developing anemia. This study contributes evidence that the TLV should be considered for adoption as the new PEL.

Preparing Educational Leaders for Rural School Districts: New Mexico's State-Wide Collaborative Approach.

ERIC Educational Resources Information Center

Milstein, Mike; And Others

Educational administration faculty from five public higher education institutions in New Mexico formed a consortium to address the need for effective educational leaders in rural school districts. Members established the New Mexico Partners for Educational Leadership (PEL), composed of faculty from the five universities, leading educational…

IKKγ-Mimetic Peptides Block the Resistance to Apoptosis Associated with Kaposi's Sarcoma-Associated Herpesvirus Infection.

PubMed

Briggs, Louise C; Chan, A W Edith; Davis, Christopher A; Whitelock, Nicholas; Hotiana, Hajira A; Baratchian, Mehdi; Bagnéris, Claire; Selwood, David L; Collins, Mary K; Barrett, Tracey E

2017-12-01

Primary effusion lymphoma (PEL) is a lymphogenic disorder associated with Kaposi's sarcoma-associated herpesvirus (KSHV) infection. Key to the survival and proliferation of PEL is the canonical NF-κB pathway, which becomes constitutively activated following overexpression of the viral oncoprotein KSHV vFLIP (ks-vFLIP). This arises from its capacity to form a complex with the modulatory subunit of the IκB kinase (IKK) kinase, IKKγ (or NEMO), resulting in the overproduction of proteins that promote cellular survival and prevent apoptosis, both of which are important drivers of tumorigenesis. Using a combination of cell-based and biophysical assays together with structural techniques, we showed that the observed resistance to cell death is largely independent of autophagy or major death receptor signaling pathways and demonstrated that direct targeting of the ks-vFLIP-IKKγ interaction both in cells and in vitro can be achieved using IKKγ-mimetic peptides. Our results further reveal that these peptides not only induce cell killing but also potently sensitize PEL to the proapoptotic agents tumor necrosis factor alpha and etoposide and are the first to confirm ks-vFLIP as a tractable target for the treatment of PEL and related disorders. IMPORTANCE KSHV vFLIP (ks-vFLIP) has been shown to have a crucial role in cellular transformation, in which it is vital for the survival and proliferation of primary effusion lymphoma (PEL), an aggressive malignancy associated with infection that is resistant to the majority of chemotherapeutic drugs. It operates via subversion of the canonical NF-κB pathway, which requires a physical interaction between ks-vFLIP and the IKK kinase modulatory subunit IKKγ. While this interaction has been directly linked to protection against apoptosis, it is unclear whether the suppression of other cell death pathways implicated in ks-vFLIP pathogenesis is an additional contributor. We demonstrate that the interaction between ks-vFLIP and IKKγ is pivotal in conferring resistance to apoptosis. Additionally, we show that the ks-vFLIP-IKKγ complex can be disrupted using peptides leading to direct killing and the sensitization of PEL cells to proapoptotic agents. Our studies thus provide a framework for future therapeutic interventions. Copyright © 2017 Briggs et al.

Potential Energy Landscape of the Liquid-Liquid Phase Transition in Water and the transformation between Low-Density and High-Density Amorphous Ice

NASA Astrophysics Data System (ADS)

Giovambattista, N.; Sciortino, F.; Starr, F. W.; Poole, P. H.

The potential energy landscape (PEL) formalism is a valuable approach within statistical mechanics for describing supercooled liquids and glasses. We use the PEL formalism and computer simulations to study the transformation between low-density (LDL) and high-density liquid (HDL) water, and between low-density (LDA) and high-density amorphous ice (HDA). We employ the ST2 water model that exhibits a LDL-HDL first-order phase transition and a sharp LDA-HDA transformation, as observed in experiments. Our results are consistent with the view that LDA and HDA configurations are associated with two distinct regions (megabasins) of the PEL that are separated by a potential energy barrier. At higher temperature, we find that LDL configurations are located in the same megabasin as LDA, and that HDL configurations are located in the same megabasin as HDA. We show that the pressure-induced LDL-HDL and LDA-HDA transformations occur along paths that interconnect these two megabasins, but that the path followed by the liquid and the amorphous ice differ. We also study the liquid-to-ice-VII first-order phase transition. The PEL properties across this transition are qualitatively similar to the changes found during the LDA-HDA transformation, supporting the interpretation that the LDA-HDA transformation is a first-order-like phase transition between out-of-equilibrium states.

Final Environmental Impact Statement Evolved Expendable Launch Vehicle Program

DTIC Science & Technology

1998-04-01

source, permit application compliance, permit issuance, renewal and revision, and permit review by the U.S. EPA and any affected states. Because...Quality Standards NH3 = ammonia NOx = nitrogen oxides OSHA = Occupational Safety and Health Administration PEL = Permissible Exposure Level ppm = parts...NO or NO2 incremental concentrations during an abort were predicted by REEDM for only the DIV-S vehicle configuration. Ammonia was predicted by REEDM

Directed Evolution and Structural Analysis of Alkaline Pectate Lyase from the Alkaliphilic Bacterium Bacillus sp. Strain N16-5 To Improve Its Thermostability for Efficient Ramie Degumming.

PubMed

Zhou, Cheng; Ye, Jintong; Xue, Yanfen; Ma, Yanhe

2015-09-01

Thermostable alkaline pectate lyases have potential applications in the textile industry as an alternative to chemical-based ramie degumming processes. In particular, the alkaline pectate lyase from Bacillus sp. strain N16-5 (BspPelA) has potential for enzymatic ramie degumming because of its high specific activity under extremely alkaline conditions without the requirement for additional Ca(2+). However, BspPelA displays poor thermostability and is inactive after incubation at 50°C for only 30 min. Here, directed evolution was used to improve the thermostability of BspPelA for efficient and stable degumming. After two rounds of error-prone PCR and screening of >12,000 mutants, 10 mutants with improved thermostability were obtained. Sequence analysis and site-directed mutagenesis revealed that single E124I, T178A, and S271G substitutions were responsible for improving thermostability. Structural and molecular dynamic simulation analysis indicated that the formation of a hydrophobic cluster and new H-bond networks was the key factor contributing to the improvement in thermostability with these three substitutions. The most thermostable combined mutant, EAET, exhibited a 140-fold increase in the t50 (time at which the enzyme loses 50% of its initial activity) value at 50°C, accompanied by an 84.3% decrease in activity compared with that of wild-type BspPelA, while the most advantageous combined mutant, EA, exhibited a 24-fold increase in the t50 value at 50°C, with a 23.3% increase in activity. Ramie degumming with the EA mutant was more efficient than that with wild-type BspPelA. Collectively, our results suggest that the EA mutant, exhibiting remarkable improvements in thermostability and activity, has the potential for applications in ramie degumming in the textile industry. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Directed Evolution and Structural Analysis of Alkaline Pectate Lyase from the Alkaliphilic Bacterium Bacillus sp. Strain N16-5 To Improve Its Thermostability for Efficient Ramie Degumming

PubMed Central

Zhou, Cheng; Ye, Jintong; Xue, Yanfen

2015-01-01

Thermostable alkaline pectate lyases have potential applications in the textile industry as an alternative to chemical-based ramie degumming processes. In particular, the alkaline pectate lyase from Bacillus sp. strain N16-5 (BspPelA) has potential for enzymatic ramie degumming because of its high specific activity under extremely alkaline conditions without the requirement for additional Ca2+. However, BspPelA displays poor thermostability and is inactive after incubation at 50°C for only 30 min. Here, directed evolution was used to improve the thermostability of BspPelA for efficient and stable degumming. After two rounds of error-prone PCR and screening of >12,000 mutants, 10 mutants with improved thermostability were obtained. Sequence analysis and site-directed mutagenesis revealed that single E124I, T178A, and S271G substitutions were responsible for improving thermostability. Structural and molecular dynamic simulation analysis indicated that the formation of a hydrophobic cluster and new H-bond networks was the key factor contributing to the improvement in thermostability with these three substitutions. The most thermostable combined mutant, EAET, exhibited a 140-fold increase in the t50 (time at which the enzyme loses 50% of its initial activity) value at 50°C, accompanied by an 84.3% decrease in activity compared with that of wild-type BspPelA, while the most advantageous combined mutant, EA, exhibited a 24-fold increase in the t50 value at 50°C, with a 23.3% increase in activity. Ramie degumming with the EA mutant was more efficient than that with wild-type BspPelA. Collectively, our results suggest that the EA mutant, exhibiting remarkable improvements in thermostability and activity, has the potential for applications in ramie degumming in the textile industry. PMID:26070675

Extracavitary/solid variant of primary effusion lymphoma presenting as a gastric mass.

PubMed

Liao, Guanghong; Cai, Junchao; Yue, Changjun; Qing, Xin

2015-12-01

Primary effusion lymphoma (PEL) is a rare subtype of large B-cell lymphoma associated with human herpesvirus 8 (HHV8). It has the highest incidence in HIV-positive individuals. It often presents as a malignant pleural, peritoneal and/or pericardial effusion without a detectable solid mass. Most cases are co-infected with Epstein-Barr virus (EBV). Rare cases of HHV8-positive lymphoma with features similar to PEL can present as tumor masses and are considered to represent an extracavitary or solid variant of PEL. We report a case of EBV negative, extracavitary/solid variant of primary effusion lymphoma presenting as a gastric mass. A 48-year-old man was admitted to an outside hospital with abdominal pain and weight loss. At the outside hospital, he was found to be HIV positive and have a 3 × 2 cm gastric mass. He was subsequently diagnosed with ALK negative anaplastic large cell lymphoma by gastric biopsy. The patient was referred to Harbor-UCLA Medical Center for further management. Review of the outside slides and additional stains performed at our hospital revealed sheets of large anaplastic lymphoma cells that were positive for CD30, CD138, MUM1 and HHV8, focally weakly positive for CD3, and negative for other T- and B-cell markers and EBER, consistent with extracavitary/solid variant of primary effusion lymphoma. Interestingly, for the first time, cyclin D1 positivity was also demonstrated in PEL. Primary effusion lymphoma, particularly the extracavitary/solid variant, is very rare, and the diagnosis can be challenging. In some cases, when CD30 is uniformly positive, this lymphoma can be misdiagnosed as ALK negative anaplastic large cell lymphoma. This lymphoma can also aberrantly express T-cell markers as seen in this case, making diagnosis even more difficult. Awareness of the existence and the features of solid variant PEL and assessment for HHV8 infection are essential for correct diagnosis. Published by Elsevier Inc.

Potential energy landscape of the apparent first-order phase transition between low-density and high-density amorphous ice.

PubMed

Giovambattista, Nicolas; Sciortino, Francesco; Starr, Francis W; Poole, Peter H

2016-12-14

The potential energy landscape (PEL) formalism is a valuable approach within statistical mechanics to describe supercooled liquids and glasses. Here we use the PEL formalism and computer simulations to study the pressure-induced transformations between low-density amorphous ice (LDA) and high-density amorphous ice (HDA) at different temperatures. We employ the ST2 water model for which the LDA-HDA transformations are remarkably sharp, similar to what is observed in experiments, and reminiscent of a first-order phase transition. Our results are consistent with the view that LDA and HDA configurations are associated with two distinct regions (megabasins) of the PEL that are separated by a potential energy barrier. At higher temperature, we find that low-density liquid (LDL) configurations are located in the same megabasin as LDA, and that high-density liquid (HDL) configurations are located in the same megabasin as HDA. We show that the pressure-induced LDL-HDL and LDA-HDA transformations occur along paths that interconnect these two megabasins, but that the path followed by the liquid is different from the path followed by the amorphous solid. At higher pressure, we also study the liquid-to-ice-VII first-order phase transition, and find that the behavior of the PEL properties across this transition is qualitatively similar to the changes found during the LDA-HDA transformation. This similarity supports the interpretation that the LDA-HDA transformation is a first-order phase transition between out-of-equilibrium states. Finally, we compare the PEL properties explored during the LDA-HDA transformations in ST2 water with those reported previously for SPC/E water, for which the LDA-HDA transformations are rather smooth. This comparison illuminates the previous work showing that, at accessible computer times scales, a liquid-liquid phase transition occurs in the case of ST2 water, but not for SPC/E water.

Potential energy landscape of the apparent first-order phase transition between low-density and high-density amorphous ice

NASA Astrophysics Data System (ADS)

Giovambattista, Nicolas; Sciortino, Francesco; Starr, Francis W.; Poole, Peter H.

2016-12-01

The potential energy landscape (PEL) formalism is a valuable approach within statistical mechanics to describe supercooled liquids and glasses. Here we use the PEL formalism and computer simulations to study the pressure-induced transformations between low-density amorphous ice (LDA) and high-density amorphous ice (HDA) at different temperatures. We employ the ST2 water model for which the LDA-HDA transformations are remarkably sharp, similar to what is observed in experiments, and reminiscent of a first-order phase transition. Our results are consistent with the view that LDA and HDA configurations are associated with two distinct regions (megabasins) of the PEL that are separated by a potential energy barrier. At higher temperature, we find that low-density liquid (LDL) configurations are located in the same megabasin as LDA, and that high-density liquid (HDL) configurations are located in the same megabasin as HDA. We show that the pressure-induced LDL-HDL and LDA-HDA transformations occur along paths that interconnect these two megabasins, but that the path followed by the liquid is different from the path followed by the amorphous solid. At higher pressure, we also study the liquid-to-ice-VII first-order phase transition, and find that the behavior of the PEL properties across this transition is qualitatively similar to the changes found during the LDA-HDA transformation. This similarity supports the interpretation that the LDA-HDA transformation is a first-order phase transition between out-of-equilibrium states. Finally, we compare the PEL properties explored during the LDA-HDA transformations in ST2 water with those reported previously for SPC/E water, for which the LDA-HDA transformations are rather smooth. This comparison illuminates the previous work showing that, at accessible computer times scales, a liquid-liquid phase transition occurs in the case of ST2 water, but not for SPC/E water.

Secondary toxicity in raptors caused by white phosphorus

USGS Publications Warehouse

Sparling, D.W.

1995-01-01

White phosphorus (WP) has caused waterfowl die-offs in a tidal saltmarsh used by the U.S. Army for artillery practice for > 40 years. Bald (Haliaeetus leucocephalus)and golden (Aquila chrysaetos) eagles have been observed feeding on dead and dying waterfowl on the marsh and may be exposed to WP through ingestion of contaminated birds. One carcass of each eagle species has been found with measurable levels of WP in fat. To determine if raptors can become intoxicated by ingesting prey that have been exposed to WP we fed live, 10-day-old white leghorn chicks three sublethal doses of WP. Six hrs after the last dose we euthanized the chicks and separated them into two groups--one with the digestive system from gizzard anteriorly removed (NoGut) and one with the digestive system intact and a 1.1 mg pellet of WP implanted deep into the crop (Pel). A third group of same-aged chicks unexposed to WP was used for controls. Fifteen kestrels (Fa/co sparverius) were randomly assigned to each of the treatments and 10 to the control diet. By 7 d of the study 8 of the kestrels had died on the Pel and 3 on the NoGut diet. Survivors on the Pel diet had significantly lower hematocrit, hemoglobin, final body weights and greater liver/body weight ratios and weight loss than control birds. The study showed that raptors and possibly other predators are at risk both when consuming flesh of prey that have succumbed to WP poisoning and when ingesting WP pellets that are incorporated in body parts but that the risk is greater when pellets are present.

The Effect of the Pore Entrance on Particle Motion in Slit Pores: Implications for Ultrathin Membranes

PubMed Central

Delavari, Armin; Baltus, Ruth

2017-01-01

Membrane rejection models generally neglect the effect of the pore entrance on intrapore particle transport. However, entrance effects are expected to be particularly important with ultrathin membranes, where membrane thickness is typically comparable to pore size. In this work, a 2D model was developed to simulate particle motion for spherical particles moving at small Re and infinite Pe from the reservoir outside the pore into a slit pore. Using a finite element method, particles were tracked as they accelerated across the pore entrance until they reached a steady velocity in the pore. The axial position in the pore where particle motion becomes steady is defined as the particle entrance length (PEL). PELs were found to be comparable to the fluid entrance length, larger than the pore size and larger than the thickness typical of many ultrathin membranes. Results also show that, in the absence of particle diffusion, hydrodynamic particle–membrane interactions at the pore mouth result in particle “funneling” in the pore, yielding cross-pore particle concentration profiles focused at the pore centerline. The implications of these phenomena on rejection from ultrathin membranes are examined. PMID:28796197

Effect of artificial aging on the bond durability of fissure sealants.

PubMed

Yun, Xiaofei; Li, Wei; Ling, Chen; Fok, Alex

2013-06-01

To evaluate the effect of artificial aging on the bond durability of fissure sealants in vitro. Twenty bovine incisors received 4 different sealant treatments and were divided into four groups: 1. Ultraseal XT plus (UX); 2. Enamel Loc (EL); 3. 35% phosphoric acid plus Enamel Loc (PEL); 4. Adper Prompt L-Pop plus Clinpro (PPC). Beam-shaped specimens were prepared and randomly divided into three subgroups. One subgroup underwent the microtensile bond strength (µTBS) test after 24-h storage in 37°C water. The other two subgroups were also subjected to the microtensile bond strength test after 5000 and 10,000 thermal cycles, respectively. Another twelve intact human third molars were sealed using 1 of 3 methods and were divided into 3 groups of 4 each: 1. Ultraseal XT plus; 2. Adper Prompt L-Pop plus Clinpro; and 3. Enamel Loc. Two specimens from each group were immersed in a 50% silver nitrate solution for 24 h, followed by exposure to fluorescent light for 8 h, before being scanned in a micro-CT (microcomputer tomography) machine. The other two were handled in the same way after undergoing 10,000 thermal cycles. The CT images obtained were evaluated. All samples from the EL group were broken during preparation, so no µTBS results were available. After 5000 thermal cycles, the bond strengths of the three other groups (UX, PEL, PPC) decreased significantly (p < 0.05). Longer thermocycling (10,000 cycles) resulted in more decreases in µTBS for group PEL and PPC, while the strength of the UX group remained relatively unchanged. After thermocycling, considerable silver penetration could be seen at the sealant/enamel interface of the EL group in micro-CT images. The etch-and-rinse procedure for sealant application promotes higher bond strength under artificial aging. Micro-CT, a nondestructive analytical tool, may be used to evaluate the sealant/enamel interface effectively.

Lymphoid disorders associated with HHV-8/KSHV infection: facts and contentions.

PubMed

Gaidano, G; Castaños-Velez, E; Biberfeld, P

1999-04-01

Following the demonstration in 1994, that Kaposi's sarcoma (KS) was associated with a novel virus (KSHV or HHV-8) belonging to the lymphotropic herpes family, this virus was also found in certain lymphoid neoplasias of immunodeficient (HIV+) and immune competent hosts. The association of HHV-8/KSHV infection is now well established with primary effusion lymphoma (PEL) or body cavity based lymphoma (BCBL) and multicentric Castleman's disease (MCD) of the plasma cell type. A possible pathogenic role of HHV-8/KSHV in other lymphoid tumours including primary central nervous system lymphoma (PCNSL) and multiple myeloma (MM) as well as some atypical lymphoproliferations and sarcoidosis has also been suggested, but this is at present a controversial matter, or not confirmed. Several HHV-8/KSHV genes, including potential oncogenes, genes homologous to various cellular genes and growth factors have been incriminated in the pathogenesis of KS and PEL/BCBL, but a common pathogenic mechanism for the clearly diverse proliferations represented by PEL, MCD and KS is at present not evident.

Coupled Transcriptome and Proteome Analysis of Human Lymphotropic Tumor Viruses: Insights on the Detection and Discovery of Viral Genes

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

Dresang, Lindsay R.; Teuton, Jeremy R.; Feng, Huichen

Kaposi's sarcoma-associated herpesvirus (KSHV) and Epstein-Barr virus (EBV) are related human tumor viruses that cause primary effusion lymphomas (PEL) and Burkitt's lymphomas (BL), respectively. Viral genes expressed in naturally-infected cancer cells contribute to disease pathogenesis; knowing which viral genes are expressed is critical in understanding how these viruses cause cancer. To evaluate the expression of viral genes, we used high-resolution separation and mass spectrometry coupled with custom tiling arrays to align the viral proteomes and transcriptomes of three PEL and two BL cell lines under latent and lytic culture conditions. Results The majority of viral genes were efficiently detected atmore » the transcript and/or protein level on manipulating the viral life cycle. Overall the correlation of expressed viral proteins and transcripts was highly complementary in both validating and providing orthogonal data with latent/lytic viral gene expression. Our approach also identified novel viral genes in both KSHV and EBV, and extends viral genome annotation. Several previously uncharacterized genes were validated at both transcript and protein levels. Conclusions This systems biology approach coupling proteome and transcriptome measurements provides a comprehensive view of viral gene expression that could not have been attained using each methodology independently. Detection of viral proteins in combination with viral transcripts is a potentially powerful method for establishing virus-disease relationships.« less

Novel use of pleural ultrasound can identify malignant entrapped lung prior to effusion drainage.

PubMed

Salamonsen, Matthew R; Lo, Ada K C; Ng, Arnold C T; Bashirzadeh, Farzad; Wang, William Y S; Fielding, David I K

2014-11-01

The presence of entrapped lung changes the appropriate management of malignant pleural effusion from pleurodesis to insertion of an indwelling pleural catheter. No methods currently exist to identify entrapped lung prior to effusion drainage. Our objectives were to develop a method to identify entrapped lung using tissue movement and deformation (strain) analysis with ultrasonography and compare it to the existing technique of pleural elastance (PEL). Prior to drainage, 81 patients with suspected malignant pleural effusion underwent thoracic ultrasound using an echocardiogram machine. Images of the atelectatic lower lobe were acquired during breath hold, allowing motion and strain related to the cardiac impulse to be analyzed using motion mode (M mode) and speckle-tracking imaging, respectively. PEL was measured during effusion drainage. The gold-standard diagnosis of entrapped lung was the consensus opinion of two interventional pulmonologists according to postdrainage imaging. Participants were randomly divided into development and validation sets. Both total movement and strain were significantly reduced in entrapped lung. Using data from the development set, the area under the receiver-operating curves for the diagnosis of entrapped lung was 0.86 (speckle tracking), 0.79 (M mode), and 0.69 (PEL). Using respective cutoffs of 6%, 1 mm, and 19 cm H2O on the validation set, the sensitivity/specificity was 71%/85% (speckle tracking), 50%/85% (M mode), and 40%/100% (PEL). This novel ultrasound technique can identify entrapped lung prior to effusion drainage, which could allow appropriate choice of definitive management (pleurodesis vs indwelling catheter), reducing the number of interventions required to treat malignant pleural effusion.

Fuel cells, electrolyzers, and microalgae photobioreactors: technologies for long-duration missions in human spaceflight

NASA Astrophysics Data System (ADS)

Belz, Stefan; Bretschneider, Jens; Nathanson, Emil; Buchert, Melanie

Long-duration and far-distant missions in human spaceflight have higher requirements on life support systems (LSS) technologies than for missions into low Earth orbit (LEO). LSS technologies have to ensure that humans can survive, live, and work in space. Enhancements of existing technologies, new technological developments and synergetic components integration help to close the oxygen, water and carbon loops. For these reasons, the approach of a synergetic integration of Polymer Electrolyte Membrane Fuel Cells (PEFC), Polymer Electrolyte Membrane Electrolyzers (PEL) and Photobioreactors (PBR) for microalgae cultivation into the LSS is investigated. It is demonstrated in which mission scenarii the application of PEFC, PEL, and PBR are useful in terms of mass, reliability, and cycle closures. The paper represents the current status of research at the Institute of Space Systems (IRS) of University of Stuttgart on PEFC, PEL, and PBR development. A final configuration of a prototype of a PEFC system includes the gas, water, and thermal management. The PEL is a state-of-the-art technology for space application, but the specific requirements by a synergetic integration are focused. A prototype configuration of a PBR system, which was tested under microgravity conditions in a parabolic experiment, consists of a highly sophisticated cultivation chamber, adapted sensorics, pumps, nutrients supply and harvesting unit. Additionally, the latest results of the cultivation of the microalgae species Chlorella vulgaris and Scenedesmus obliquus in the laboratories of the IRS are represented. Both species are robust, nutrient-rich for human diet. An outlook of the next steps is given for in-orbit verification.

The recent pumice eruptions of Mt. Pelée volcano, Martinique. Part I: Depositional sequences, description of pumiceous deposits

NASA Astrophysics Data System (ADS)

Traineau, Hervé; Westercamp, Denis; Bardintzeff, Jacques-Marie; Miskovsky, Jean-Claude

1989-08-01

Mount Pelée is one of the most active volcanoes of the Lesser Antilles arc, with more than twenty eruptions over the last 5000 years. Both nuée ardente-type eruptions, which are well known, and pumice eruptions, although little known, are very common in the stratigraphic record. The four younger pumice eruptions, P4 (2440 y.B.P.), P3 (2010 y.B.P.), P2 (1670 y.B.P.) and P1 (650 y.B.P.) can be used to reconstruct the eruption sequences. The various pumiceous deposits can be described as fine lithic ash layer, Plinian fall deposits, pumice and ash flow deposits with associated ash cloud fall deposits, and pumice surge deposits. Three kinds of depositional sequences have been defined. The distinctions between them are based on the occurrence of an initial Plinian phase and the generation of intraflow pyroclastic surges. The pumice eruptions of Mt. Pelée are small in intensity and magnitude, as expressed by the dispersal of their products and by the total mass of erupted material which is estimated to be less than 1 km 3 in each case. The pumice fall deposits have dispersal characteristics of small Plinian eruptions, close to the sub-Plinian type. Nevertheless, the probability of an occurrence of a new pumice eruption at Mt. Pelée is high, and the widespread distribution of pumice deposits around the volcano suggests that such an eruption is a major volcanic risk during the present stage of activity.

Assessment of arsenic exposures and controls in gallium arsenide production.

PubMed

Sheehy, J W; Jones, J H

1993-02-01

The electronics industry is expanding the use of gallium arsenide in the production of optoelectronic devices and integrated circuits. Workers in the electronics industry using gallium arsenide are exposed to hazardous substances such as arsenic, arsine, and various acids. Arsenic requires stringent controls to minimize exposures (the current OSHA PEL for arsenic is 10 micrograms/m3 and the NIOSH REL is 2 micrograms/m3 ceiling). Inorganic arsenic is strongly implicated in respiratory tract and skin cancer. For these reasons, NIOSH researchers conducted a study of control systems for facilities using gallium arsenide. Seven walk-through surveys were performed to identify locations for detailed study which appeared to have effective controls; three facilities were chosen for in-depth evaluation. The controls were evaluated by industrial hygiene sampling. Including personal breathing zone and area air sampling for arsenic and arsine; wipe samples for arsenic also were collected. Work practices and the use of personal protective equipment were documented. This paper reports on the controls and the arsenic exposure results from the evaluation of the following gallium arsenide processes: Liquid Encapsulated Czochralski (LEC) and Horizontal Bridgeman (HB) crystal growing, LEC cleaning operations, ingot grinding/wafer sawing, and epitaxy. Results at one plant showed that in all processes except epitaxy, average arsenic exposures were at or above the OSHA action level of 5 micrograms/m3. While cleaning the LEC crystal pullers, the average potential arsenic exposure of the cleaning operators was 100 times the OSHA PEL. At the other two plants, personal exposures for arsenic were well controlled in LEC, LEC cleaning, grinding/sawing, and epitaxy operations.

Bioavailability assessment of toxic metals using the technique "acid-volatile sulfide (AVS)-simultaneously extracted metals (SEM)" in marine sediments collected in Todos os Santos Bay, Brazil.

PubMed

Silva, Jucelino B; Nascimento, Rodrigo A; de Oliva, Sergio T; de Oliveira, Olívia M C; Ferreira, Sergio L C

2015-10-01

This paper reports the bioavailability of the metals (cadmium, copper, zinc, lead, and nickel) in sediment samples collected in seven stations from the São Paulo Estuary, Todos os Santos Bay, Brazil. The bioavailability was determined by employing the technique "acid-volatile sulfide (AVS) and simultaneously extracted metal (SEM)". The elements cadmium, copper, lead, and zinc were determined using differential pulse anodic stripping voltammetry (DPASV), while nickel was quantified utilizing electrothermal atomic absorption spectrometry (ET AAS). The accuracy of these methods was confirmed using a certified reference material of estuarine sediment (NIST 1646). The sulfide was quantified using potentiometry with selective electrode and the organic matter determination employing an indirect volumetric method using potassium dichromate and iron(II) sulfate solutions. The bioavailability of the metals was estimated by relationship between the concentration of AVS and the sum of the concentrations of the simultaneously extracted metals (ΣSEM), considering a significant toxicity when (ΣSEM)/(AVS) is higher than 1. The bioavailability values in the seven stations studied varied from 0.93 to 1.31 (June, 2014) and from 0.34 to 0.58 (September, 2014). These results demonstrated a critical condition of toxicity (bioavailability >1) in six of the seven sediment samples collected during the rainy season (June, 2014). In the other period (September, 2014), the bioavailability was always lower than 1 for all sediment samples collected in the seven stations. The individual values of the concentrations of the five metals were compared with the parameters PEL (probable effects level) and TEL (threshold effects level), which are commonly employed for characterization of ecological risk in environmental systems. This comparison revealed that all metals have concentrations lower than the PEL and only zinc and lead in some stations have contents higher than the TEL. The bioavailability evaluation and the concentrations achieved for the five elements in the sediments samples analyzed demonstrated that the ecosystem studied does not present an environmental risk.

High-throughput screening using the differential radial capillary action of ligand assay identifies ebselen as an inhibitor of diguanylate cyclases.

PubMed

Lieberman, Ori J; Orr, Mona W; Wang, Yan; Lee, Vincent T

2014-01-17

The rise of bacterial resistance to traditional antibiotics has motivated recent efforts to identify new drug candidates that target virulence factors or their regulatory pathways. One such antivirulence target is the cyclic-di-GMP (cdiGMP) signaling pathway, which regulates biofilm formation, motility, and pathogenesis. Pseudomonas aeruginosa is an important opportunistic pathogen that utilizes cdiGMP-regulated polysaccharides, including alginate and pellicle polysaccharide (PEL), to mediate virulence and antibiotic resistance. CdiGMP activates PEL and alginate biosynthesis by binding to specific receptors including PelD and Alg44. Mutations that abrogate cdiGMP binding to these receptors prevent polysaccharide production. Identification of small molecules that can inhibit cdiGMP binding to the allosteric sites on these proteins could mimic binding defective mutants and potentially reduce biofilm formation or alginate secretion. Here, we report the development of a rapid and quantitative high-throughput screen for inhibitors of protein-cdiGMP interactions based on the differential radial capillary action of ligand assay (DRaCALA). Using this approach, we identified ebselen as an inhibitor of cdiGMP binding to receptors containing an RxxD domain including PelD and diguanylate cyclases (DGC). Ebselen reduces diguanylate cyclase activity by covalently modifying cysteine residues. Ebselen oxide, the selenone analogue of ebselen, also inhibits cdiGMP binding through the same covalent mechanism. Ebselen and ebselen oxide inhibit cdiGMP regulation of biofilm formation and flagella-mediated motility in P. aeruginosa through inhibition of diguanylate cyclases. The identification of ebselen provides a proof-of-principle that a DRaCALA high-throughput screening approach can be used to identify bioactive agents that reverse regulation of cdiGMP signaling by targeting cdiGMP-binding domains.

An exposure study of bystanders and workers during the installation and removal of asbestos gaskets and packing.

PubMed

Mangold, Carl; Clark, Katherine; Madl, Amy; Paustenbach, Dennis

2006-02-01

From 1982 until 1991, a series of studies was performed to evaluate the airborne concentration of chrysotile asbestos associated with replacing gaskets and packing materials. These studies were conducted by the senior author in response to concerns raised by a report from the Navy in 1978 on asbestos exposures associated with gasket work. A series of studies was conducted because results of those who worked with gaskets within the Navy study did not address the background concentrations of asbestos in the work areas, which may have been significant due to the presence of asbestos insulation in the ships and shipyards. The intent of the studies performed from 1982 through 1991 was to re-create the Navy's work practices in a contaminant-free environment during an 8-hour workday (so the data could be compared with the OSHA permissible exposure limit [PEL]). Samples were collected to characterize personal and area airborne asbestos concentrations associated with the formation, removal, and storage of gaskets, as well as the scraping of flanges and the replacement of valve packing. The results indicate that the 8-hour time-weighted average (TWA) exposures of pipefitters and other tradesmen who performed these activities were below the current PEL and all previous PELs. Specifically, the highest average 8-hour TWA concentration measured for workers manipulating asbestos gaskets during this study was 0.030 f/cc (during gasket removal and flange face scraping onboard a naval ship). Likewise, the 8-hour TWA breathing zone concentrations of a worker removing and replacing asbestos valve packing did not exceed 0.016 f/cc. In most cases, the concentrations were not distinguishable from ambient levels of asbestos in the ships or the general environment. These results are not surprising given that asbestos fibers in gasket materials are encapsulated within a binder.

Permissible Exposure Level for Lunar Dusts: Gaps are Closing

NASA Technical Reports Server (NTRS)

James, John T.; Lam, Chiu-Wing; Scully Robert; Santana, Patricia; Cooper, Bonnie; McKay, David; Zeidler-Erdely, Patti C.; Castranova, Vincent

2010-01-01

Space faring nations plan to return human explorers to the moon within the next decade. Experience during the Apollo flights suggests that lunar dust will invariably get into the habitat where the finest portion (less than 5 micrometers) could be inhaled by the crew before it is cleared from the atmosphere. NASA is developing a database from which a 6-month, episodic exposure standard for lunar dust can be set. Three kinds of moon dust were prepared from a parent sample of Apollo 14 regolith #14003,96. Our goal was to prepare each type of dust sample with a mean diameter less than 2 m, which is suitable for instillation into the lungs of rats. The three samples were prepared as follows: separation from the parent sample using a fluidized bed, grinding using a jet mill grinder, or grinding with a ball-mill grinder. Grinding simulated restoration of surface activation of dust expected to occur at the surface of the moon on native lunar dust. We used two grinding methods because they seemed to produce different modes of activation. The effects of grinding were preserved by maintaining the dust in ultra-pure nitrogen until immediately before it was placed in suspension for administration to rats. The dust was suspended in physiological saline with 10% Survanta, a lung surfactant. Rats were given intratrachael instillations of the dust suspension at three doses. In addition to the three moon dusts (A, C and E), we instilled the same amount of a negative control (TiO2, B) and a highly-toxic, positive control (quartz, D). These additional mineral dusts were selected because they have well-established and very different permissible exposure levels (PELs). Our goal was to determine where lunar dusts fit between these extremes, and then estimate a PEL for each lunar dust. We evaluated many indices of toxicity to the lung. The figure shows the changes in lactate dehydrogenase (LDH), a marker of cell death, for the five dusts. Benchmark dose software (Version 2.1.2) from the Environmental Protection Agency was used to estimate the 10% effect levels (BMD(sub 10)) using five models. The best-fitting model was used to estimate the optimal BMD(sub 10) (table)

Calculation and evaluation of sediment effect concentrations for the amphipod Hyalella azteca and the midge Chironomus riparius

USGS Publications Warehouse

Ingersoll, Christopher G.; Haverland, Pamela S.; Brunson, Eric L.; Canfield, Timothy J.; Dwyer, F. James; Henke, Chris; Kemble, Nile E.; Mount, David R.; Fox, Richard G.

1996-01-01

Procedures are described for calculating and evaluating sediment effect concentrations (SECs) using laboratory data on the toxicity of contaminants associated with field-collected sediment to the amphipod Hyalella azteca and the midge Chironomus riparius. SECs are defined as the concentrations of individual contaminants in sediment below which toxicity is rarely observed and above which toxicity is frequently observed. The objective of the present study was to develop SECs to classify toxicity data for Great Lake sediment samples tested with Hyalella azteca and Chironomus riparius. This SEC database included samples from additional sites across the United States in order to make the database as robust as possible. Three types of SECs were calculated from these data: (1) Effect Range Low (ERL) and Effect Range Median (ERM), (2) Threshold Effect Level (TEL) and Probable Effect Level (PEL), and (3) No Effect Concentration (NEC). We were able to calculate SECs primarily for total metals, simultaneously extracted metals, polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs). The ranges of concentrations in sediment were too narrow in our database to adequately evaluate SECs for butyltins, methyl mercury, polychlorinated dioxins and furans, or chlorinated pesticides. About 60 to 80% of the sediment samples in the database are correctly classified as toxic or not toxic depending on type of SEC evaluated. ERMs and ERLs are generally as reliable as paired PELs and TELs at classifying both toxic and non-toxic samples in our database. Reliability of the SECs in terms of correctly classifying sediment samples is similar between ERMs and NECs; however, ERMs minimize Type I error (false positives) relative to ERLs and minimize Type II error (false negatives) relative to NECs. Correct classification of samples can be improved by using only the most reliable individual SECs for chemicals (i.e., those with a higher percentage of correct classification). SECs calculated using sediment concentrations normalized to total organic carbon (TOC) concentrations did not improve the reliability compared to SECs calculated using dry-weight concentrations. The range of TOC concentrations in our database was relatively narrow compared to the ranges of contaminant concentrations. Therefore, normalizing dry-weight concentrations to a relatively narrow range of TOC concentrations had little influence on relative concentra of contaminants among samples. When SECs are used to conduct a preliminary screening to predict the potential for toxicity in the absence of actual toxicity testing, a low number of SEC exceedances should be used to minimize the potential for false negatives; however, the risk of accepting higher false positives is increased.

Pre-oxidation for Colorimetric Sensor Array Detection of VOCs

PubMed Central

Lin, Hengwei; Jang, Minseok; Suslick, Kenneth S.

2011-01-01

A disposable pre-oxidation technique is reported that dramatically improves the detection and identification of volatile organic compounds (VOCs) by a colorimetric sensor array. By passing a vapor stream through a tube packed with chromic acid on silica immediately before the colorimetric sensor array, the sensitivity to less reactive VOCs is substantially increased and limits of detection (LODs) are improved ~300-fold, permitting the detection, identification, and discrimination of 20 commonly found indoor VOC pollutants at both their immediately dangerous to life or health (IDLH) and at permissible exposure limits (PEL) concentrations. LODs of these pollutants were on average 1.4% of their respective PELs. PMID:21967478

A simple and highly sensitive colorimetric detection method for gaseous formaldehyde.

PubMed

Feng, Liang; Musto, Christopher J; Suslick, Kenneth S

2010-03-31

A colorimetric detection method using amine-functionalized polymer films doped with a pH indicator has been developed for the rapid, sensitive, and quantitative detection of gaseous formaldehyde at concentrations well below the immediately dangerous to life or health (IDLH) limit. In 1 min, visible color changes are easily observed, even down to the permissible exposure limit (PEL) at 750 ppb. The limit of detection is below 50 ppb (7% of the PEL) after 10 min of exposure. This sensor is essentially unaffected by changes in humidity or temperature (4 to 50 degrees C) and is not sensitive to common interferents.

Two Genetic Loci Produce Distinct Carbohydrate-Rich Structural Components of the Pseudomonas aeruginosa Biofilm Matrix

PubMed Central

Friedman, Lisa; Kolter, Roberto

2004-01-01

Pseudomonas aeruginosa forms biofilms, which are cellular aggregates encased in an extracellular matrix. Molecular genetics studies of three common autoaggregative phenotypes, namely wrinkled colonies, pellicles, and solid-surface-associated biofilms, led to the identification of two loci, pel and psl, that are involved in the production of carbohydrate-rich components of the biofilm matrix. The pel gene cluster is involved in the production of a glucose-rich matrix material in P. aeruginosa strain PA14 (L. Friedman and R. Kolter, Mol. Microbiol. 51:675-690, 2004). Here we investigate the role of the pel gene cluster in P. aeruginosa strain ZK2870 and identify a second genetic locus, termed psl, involved in the production of a mannose-rich matrix material. The 11 predicted protein products of the psl genes are homologous to proteins involved in carbohydrate processing. P. aeruginosa is thus able to produce two distinct carbohydrate-rich matrix materials. Either carbohydrate-rich matrix component appears to be sufficient for mature biofilm formation, and at least one of them is required for mature biofilm formation in P. aeruginosa strains PA14 and ZK2870. PMID:15231777

Two genetic loci produce distinct carbohydrate-rich structural components of the Pseudomonas aeruginosa biofilm matrix.

PubMed

Friedman, Lisa; Kolter, Roberto

2004-07-01

Pseudomonas aeruginosa forms biofilms, which are cellular aggregates encased in an extracellular matrix. Molecular genetics studies of three common autoaggregative phenotypes, namely wrinkled colonies, pellicles, and solid-surface-associated biofilms, led to the identification of two loci, pel and psl, that are involved in the production of carbohydrate-rich components of the biofilm matrix. The pel gene cluster is involved in the production of a glucose-rich matrix material in P. aeruginosa strain PA14 (L. Friedman and R. Kolter, Mol. Microbiol. 51:675-690, 2004). Here we investigate the role of the pel gene cluster in P. aeruginosa strain ZK2870 and identify a second genetic locus, termed psl, involved in the production of a mannose-rich matrix material. The 11 predicted protein products of the psl genes are homologous to proteins involved in carbohydrate processing. P. aeruginosa is thus able to produce two distinct carbohydrate-rich matrix materials. Either carbohydrate-rich matrix component appears to be sufficient for mature biofilm formation, and at least one of them is required for mature biofilm formation in P. aeruginosa strains PA14 and ZK2870. Copyright 2004 American Society for Microbiology

Spatial distribution, enrichment, and source of environmentally important elements in Batticaloa lagoon, Sri Lanka.

PubMed

Adikaram, Madurya; Pitawala, Amarasooriya; Ishiga, Hiroaki; Jayawardana, Daham

2017-01-01

The present paper is the first documentation of distribution and contamination status of environmentally important elements of superficial sediments in the Batticaloa lagoon that is connected to the largest bay of the world. Surface sediment samples were collected from 34 sites covering all over the lagoon. Concentrations of elements such as As, Cr, Cu, Fe, Nb, Ni, Pb, Sc, Sr, Th, V, Y, Zn, and Zr were measured by X-ray florescence analysis. Geochemically, the lagoon has three different zones that were influenced mainly by fresh water sources, marine fronts, and intermediate mixing zones. The marine sediment quality standards indicate that Zr and Th values are exceeded throughout the lagoon. According to the freshwater sediment quality standards, Cr levels of all sampling sites exceed the threshold effect level (TEL) and 17 % of them are even above the probable effect level (PEL). Most sampling sites of the channel discharging areas show minor enrichment of Cu, Ni, and Zn with respect to the TEL. Contamination indices show that the lagoon mouth area is enriched with As. Statistical analysis implies that discharges from agricultural channel and marine fluxes of the lagoon effects on the spatial distribution of measured elements. Further research is required to understand the rate of contamination in the studied marine system.

Hexavalent chromium exposure and control in welding tasks.

PubMed

Meeker, John D; Susi, Pam; Flynn, Michael R

2010-11-01

Studies of exposure to the lung carcinogen hexavalent chromium (CrVI) from welding tasks are limited, especially within the construction industry where overexposure may be common. In addition, despite the OSHA requirement that the use of engineering controls such as local exhaust ventilation (LEV) first be considered before relying on other strategies to reduce worker exposure to CrVI, data on the effectiveness of LEV to reduce CrVI exposures from welding are lacking. The goal of the present study was to characterize breathing zone air concentrations of CrVI during welding tasks and primary contributing factors in four datasets: (1) OSHA compliance data; (2) a publicly available database from The Welding Institute (TWI); (3) field survey data of construction welders collected by the Center for Construction Research and Training (CPWR); and (4) controlled welding trials conducted by CPWR to assess the effectiveness of a portable LEV unit to reduce CrVI exposure. In the OSHA (n = 181) and TWI (n = 124) datasets, which included very few samples from the construction industry, the OSHA permissible exposure level (PEL) for CrVI (5 μg/m(3)) was exceeded in 9% and 13% of samples, respectively. CrVI concentrations measured in the CPWR field surveys (n = 43) were considerably higher, and 25% of samples exceeded the PEL. In the TWI and CPWR datasets, base metal, welding process, and LEV use were important predictors of CrVI concentrations. Only weak-to-moderate correlations were found between total particulate matter and CrVI, suggesting that total particulate matter concentrations are not a good surrogate for CrVI exposure in retrospective studies. Finally, in the controlled welding trials, LEV reduced median CrVI concentrations by 68% (p = 0.02). In conclusion, overexposure to CrVI in stainless steel welding is likely widespread, especially in certain operations such as shielded metal arc welding, which is commonly used in construction. However, exposure could be substantially reduced with proper use of LEV.

Enrichment and geo-accumulation of heavy metals and risk assessment of sediments of the Kurang Nallah--feeding tributary of the Rawal Lake Reservoir, Pakistan.

PubMed

Zahra, Azmat; Hashmi, Muhammad Zaffar; Malik, Riffat Naseem; Ahmed, Zulkifl

2014-02-01

Heavy metal concentrations in sediments of the Kurang stream: a principal feeding tributary of the Rawal Lake Reservoir were investigated using enrichment factor (EF), geoaccumulation index (Igeo) and metal pollution index (MPI) to determine metal accumulation, distribution and its pollution status. Sediment samples were collected from twenty one sites during two year monitoring in pre- and post-monsoon seasons (2007-2008). Heavy metal toxicity risk was assessed using Sediment Quality Guidelines (SQGs), effect range low/effect range median values (ERL/ERM), and threshold effect level/probable effect level (TEL/PEL). Greater mean concentrations of Ni, Mn and Pb were recorded in post-monsoon season whereas metal accumulation pattern in pre-monsoon season followed the order: Zn>Mn>Ni>Cr>Co>Cd>Pb>Cu>Li. Enrichment factor (EF) and geoaccumulation (Igeo) values showed that sediments were loaded with Cd, Zn, Ni and Mn. Comparison with uncontaminated background values showed higher concentrations of Cd, Zn and Ni than respective average shale values. Concentrations of Ni and Zn were above ERL values; however, Ni concentration exceeded the ERM values. Sediment contamination was attributed to anthropogenic and natural processes. The results can be used for effective management of fresh water hilly streams of Pakistan. © 2013.

Overview Environmental Assessment for the Space Based Infrared System (SBIRS)

DTIC Science & Technology

1996-12-01

to HCl at various concentrations and durations (NASA, 1980). These insects were the honey bee , corn earworm, and lacewing. At the concentrations...bodily injury regardless of age, gender, or child-bearing status. Air Force Occupational Safety and Health Standard 48-9 establishes PELs for RF...contribute to harmful effects on the O3 layer. The actions detailed in Title VI carry out the United States obligations under the “Montreal Protocol on

The checkered puffer (Spheroides testudineus) and its helminths as bioindicators of chemical pollution in Yucatan coastal lagoons.

PubMed

Pech, Daniel; Vidal-Martínez, Víctor M; Aguirre-Macedo, M Leopoldina; Gold-Bouchot, Gerardo; Herrera-Silveira, Jorge; Zapata-Pérez, Omar; Marcogliese, David J

2009-03-15

The suitability of using helminth communities as bioindicators of environmental quality of the Yucatan coastal lagoons status was tested on the checkered puffer (Spheroides testudineus) in four coastal lagoons along the Yucatan coast. The concentration of chemical pollutants in sediments, water quality parameters, helminth infracommunity characteristics, as well as fish physiological biomarkers, including EROD (7-ethoxyresorufin-O-deethylase) and catalase activities, were measured. Results from sediment analyses demonstrated the presence of hydrocarbons, organochlorine pesticides and polychlorinated biphenyls at varying concentrations, some of which exceeded the Probability Effect Level (PEL). Significant negative associations among organochlorine pesticides, infracommunity characteristics and fish physiological responses were observed in most of the lagoons. Results suggest that EROD activity and parasite infracommunity characteristics could be useful tools to evaluate the effects of chemical pollutants on the fish host and in the environment. Importantly, certain parasites appear to influence biomarker measurements, indicating that parasites should be considered in ecotoxicological studies.

Detection of 1-O-malylglucose: pelargonidin 3-O-glucose-6''-O-malyltransferase activity in carnation (Dianthus caryophyllus).

PubMed

Abe, Yutaka; Tera, Masayuki; Sasaki, Nobuhiro; Okamura, Masachika; Umemoto, Naoyuki; Momose, Masaki; Kawahara, Nobuo; Kamakura, Hiroyuki; Goda, Yukihiro; Nagasawa, Kazuo; Ozeki, Yoshihiro

2008-09-05

Carnations have anthocyanins acylated with malate. Although anthocyanin acyltransferases have been reported in several plant species, anthocyanin malyltransferase (AMalT) activity in carnation has not been identified. Here, an acyl donor substance of AMalT, 1-O-beta-D-malylglucose, was extracted and partially purified from the petals of carnation. This was synthesized chemically to analyze AMalT activity in a crude extract from carnation. Changes in the AMalT activity showed close correlation to the accumulation of pelargonidin 3-malylglucoside (Pel 3-malGlc) during the development of red petals of carnation, but neither AMalT activity nor Pel 3-malGlc accumulation was detectable in roots, stems and leaves.

Density variations of plastic carriers in metallic glasses during aging

NASA Astrophysics Data System (ADS)

Fan, Yue; Iwashita, Takuya; Egami, Takeshi

Thermally induced deformation in metallic glasses was investigated by sampling the potential energy landscape (PEL) and probing the changes in the atomic properties (e.g. energy, displacement, stress). We demonstrate that there exists a universal plastic carrier in amorphous materials, which corresponds to the hopping between local minima on PEL. However very interestingly, the density of plastic carrier is largely affected by the aging history of the glasses. The higher fictive temperature (i . e . fast cooling rate), the larger density of plastic carrier is contained in the system. In particular, we observe a scaling of ρ~exp(- α/Tfic) , which is consistent with the prediction of shear transformation zone theory. The work is supported by U.S. Department of Energy.

Risk analysis for worker exposure to benzene

NASA Astrophysics Data System (ADS)

Hallenbeck, William H.; Flowers, Roxanne E.

1992-05-01

Cancer risk factors (characterized by route, dose, dose rate per kilogram, fraction of lifetime exposed, species, and sex) were derived for workers exposed to benzene via inhalation or ingestion. Exposure at the current Occupational Safety and Health Administration (OSHA) permissible exposure limit (PEL) and at leaking underground storage tank (LUST) sites were evaluated. At the current PEL of 1 ppm, the theoretical lifetime excess risk of cancer from benzene inhalation is ten per 1000. The theoretical lifetime excess risk for worker inhalation exposure at LUST sites ranged from 10 to 40 per 1000. These results indicate that personal protection should be required. The theoretical lifetime excess risk due to soil ingestion is five to seven orders of magnitude less than the inhalation risks.

Evaluation of Dust Exposure among the Workers in Agricultural Industries in North-East India.

PubMed

Dewangan, Krishna N; Patil, Mahesh R

2015-11-01

This study aims to quantify dust exposure among the workers in four different industrial settings: rice mills, flour mills, oil mills, and tea factories and to compare the obtained data with the permissible exposure limit (PEL) of Indian Union Ministry of Labour as well as to compare the dust exposure across activities and seasons. RespiCon(TM) particle sampler was used for collecting dust concentration in the breathing zone of the workers. In total, 149 workers participated in the study and 204 samples were collected. Samples were collected in the vicinity of different processing operations. Samples in the rice mills were collected for two consecutive years in two seasons; however samples from other industries were collected for 1 year. The results indicate that geometric mean (GM) of dust exposure was significantly (P < 0.0001) different among industrial settings. Respirable dust were 8.22, 5.76, 2.98, and 6.34mg m(-3) and total dust exposure were 81.05, 111.02, 56.68, and 39.85mg m(-3) in the rice mills, oil mills, flour mills, and tea factories, respectively. Considerable variations in dust exposure were observed in different activities in the rice and oil mills; however variation was relatively less in the flour mills and tea factories. In the rice mills, dust concentration was higher in winter than those obtained in autumn and it is significantly different (P < 0.05) for inhalable dust and total dust. Positive correlation was obtained in thoracic dust (r (2) = 0.94) and inhalable dust (r (2) = 0.97) with total dust and thoracic dust with inhalable dust (r (2) = 0.89). The results show that majority of the workers are exposed to higher level of respirable dust as compared to the PEL, while total dust exposure to all the workers were higher than the PEL; thus, immediate reduction of dust exposure among the workers is necessary for preventing respiratory system impairment. © The Author 2015. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

Lead and methylene chloride exposures among automotive repair technicians.

PubMed

Enander, Richard T; Cohen, Howard J; Gute, David M; Brown, Linfield C; Desmaris, Anne Marie C; Missaghian, Richard

2004-02-01

Potential exposures among repair technicians engaged in vehicle resurfacing operations prior to spray painting have not been thoroughly characterized. Environmental and personal air monitoring conducted in the State of Rhode Island have shown that automotive repair technicians may be exposed to metal particulates in sanding dust and methylene chloride vapors during vehicle paint removal operations. Hand wipe samples demonstrated that metals in sanding dust adhered to the hands of workers throughout the duration of the work day and were available for incidental ingestion from the handling of food/nonfood items and hand-to-mouth contact. A blood lead (PbB) screening effort among 21 workers at 2 facilities showed that 4 non-/less-exposed workers had mean PbB levels at the U.S. geometric mean of 2.8 microg/dL, while 2 out of 9 (22%) dedicated vehicle repair technicians had PbB levels at or above 30 microg Pb/dL whole blood--the level for potential adverse reproductive effects. Methylene chloride exposures were also found to exceed the Occupational Safety and Health Administrations (OSHA) 8-hr time-weighted average (TWA) action level and permissible exposure limit (PEL) in a limited number of samples (120 and 26 ppm, integrated work shift samples). Our findings suggest that thousands of professional technicians and vocational high school students may be at increased risk of adverse reproductive and/or other systemic effects.

Revision of the genus Turris Batsch, 1789 (Gastropoda: Conoidea: Turridae) with the description of six new species

PubMed Central

Kilburn, Richard N.; Fedosov, Alexander E.; Olivera, Baldomero M.

2012-01-01

The taxonomy of the genus Turris Batsch, 1789, type genus of the family Turridae, widespread in shallow-water habitats of tropic Indo-Pacific, is revised. A total of 31 species of Turris, are here recognized as valid. New species described: Turris chaldaea, Turris clausifossata, Turris guidopoppei, Turris intercancellata, Turris kantori, T. kathiewayae. Homonym renamed: Turris bipartita nom. nov. for Pleurotoma variegata Kiener, 1839 (non Philippi, 1836). New synonymies: Turris ankaramanyensis Bozzetti, 2006 = Turris tanyspira Kilburn, 1975; Turris imperfecti, T. nobilis, T. pulchra and T. tornatum Röding, 1798, and Turris assyria Olivera, Seronay & Fedosov, 2010 = T. babylonia; Turris dollyi Olivera, 2000 = Pleurotoma crispa Lamarck, 1816; Turris totiphyllis Olivera, 2000 = Turris hidalgoi Vera-Peláez, Vega-Luz & Lozano-Francisco, 2000; Turris kilburni Vera-Peláez, Vega-Luz & Lozano-Francisco, 2000 = Turris pagasa Olivera, 2000; Turris (Annulaturris) munizi Vera-Peláez, Vega-Luz & Lozano-Francisco, 2000 = Gemmula lululimi Olivera, 2000. Revised status: Turris intricata Powell, 1964, Pleurotoma variegata Kiener, 1839 (non Philippi, 1836) and Pleurotoma yeddoensis Jousseaume, 1883, are regarded as full species (not subspecies of Turris crispa). Neotype designated: For Pleurotoma garnonsii Reeve, 1843, to distinguish it from Turris garnonsii of recent authors, type locality emended to Zanzibar. New combination: Turris orthopleura Kilburn, 1983, is transferred to genus Makiyamaia, family Clavatulidae. PMID:23847408

X box binding protein XBP-1s transactivates the Kaposi's sarcoma-associated herpesvirus (KSHV) ORF50 promoter, linking plasma cell differentiation to KSHV reactivation from latency.

PubMed

Wilson, Sam J; Tsao, Edward H; Webb, Benjamin L J; Ye, Hongtao; Dalton-Griffin, Lucy; Tsantoulas, Christoforos; Gale, Catherine V; Du, Ming-Qing; Whitehouse, Adrian; Kellam, Paul

2007-12-01

Reactivation of lytic replication from viral latency is a defining property of all herpesviruses. Despite this, the authentic physiological cues for the latent-lytic switch are unclear. Such cues should ensure that viral lytic replication occurs under physiological conditions, predominantly in sites which facilitate transmission to permissive uninfected cells and new susceptible hosts. Kaposi's sarcoma-associated herpesvirus (KSHV) is associated with the B-cell neoplasm primary effusion lymphoma (PEL), in which the virus remains latent. We have previously shown that PEL cells have the gene expression profile and immunophenotype of cycling preplasma cells (plasmablasts). Here, we show that the highly active spliced isoform of plasma cell transcription factor X box binding protein 1 (XBP-1s) is a lytic switch for KSHV. XBP-1s is normally absent in PEL, but the induction of endoplasmic reticulum stress leads to XBP-1s generation, plasma cell-like differentiation, and lytic reactivation of KSHV. XBP-1s binds to and activates the KSHV immediate-early gene ORF50 and synergizes with the ORF50 gene product RTA to induce a full lytic cycle. These data suggest that KSHV remains latent until B-cell terminal differentiation into plasma cells, the transcriptional environment of which provides the physiological "lytic switch" through XBP-1s. This links B-cell terminal differentiation to KSHV lytic reactivation.

Sedimentation and occurrence and trends of selected chemical constituents in bottom sediment of 10 small reservoirs, Eastern Kansas

USGS Publications Warehouse

Juracek, Kyle E.

2004-01-01

Many municipalities in Kansas rely on small reservoirs as a source of drinking water and for recreational activities. Because of their significance to the community, management of the reservoirs and the associated basins is important to protect the reservoirs from degradation. Effective reservoir management requires information about water quality, sedimentation, and sediment quality. A combination of bathymetric surveying and bottom-sediment coring during 2002 and 2003 was used to investigate sediment deposition and the occurrence of selected nutrients (total nitrogen and total phosphorus), organic and total carbon, 26 trace elements, 15 organochlorine compounds, and 1 radionuclide in the bottom sediment of 10 small reservoirs in eastern Kansas. Original reservoir water-storage capacities ranged from 23 to 5,845 acre-feet. The mostly agricultural reservoir basins range in area from 0.6 to 14 square miles. The mean annual net volume of deposited sediment, estimated separately for several of the reservoirs, ranged from about 43,600 to about 531,000 cubic feet. The estimated mean annual net mass of deposited sediment ranged from about 1,360,000 to about 23,300,000 pounds. The estimated mean annual net sediment yields from the reservoir basins ranged from about 964,000 to about 2,710,000 pounds per square mile. Compared to sediment yield estimates provided by a statewide study published in 1965, the estimates determined in this study differed substantially and were typically smaller. A statistically significant positive correlation was determined for the relation between sediment yield and mean annual precipitation. Nutrient concentrations in the bottom sediment varied substantially among the 10 reservoirs. Median total nitrogen concentrations ranged from 1,400 to 3,700 milligrams per kilogram. Median total phosphorus concentrations ranged from 550 to 1,300 milligrams per kilogram. A statistically significant positive trend (that is, nutrient concentration increased toward the top of the sediment core) was indicated in one reservoir for total nitrogen and in two reservoirs for total phosphorus. Also, a possible positive trend for total nitrogen was indicated in two other reservoirs. These trends in nutrient concentrations may be related to a statewide increase in fertilizer use. Alternatively, the trends may be indicative of diagenesis (that is, postdepositional changes in the sediment caused by various processes including decomposition). Nutrient loads and yields also varied substantially among the five reservoirs for which loads and yields were estimated. Estimated mean annual net loads of total nitrogen deposited in the bottom sediment ranged from 4,080 to 49,100 pounds. Estimated mean annual net loads of total phosphorus deposited in the bottom sediment ranged from 1,120 to 20,800 pounds. Estimated mean annual net yields of total nitrogen from the basins ranged from 2,210 to 6,800 pounds per square mile. Estimated mean annual net yields of total phosphorus from the basins ranged from 598 to 2,420 pounds per square mile. Compared to nonenforceable sediment-quality guidelines adopted by the U.S. Environmental Protection Agency, bottom-sediment concentrations of arsenic, chromium, copper, and nickel in samples from all 10 reservoirs typically exceeded the threshold-effects levels (TELs) but were less than the probable-effects levels (PELs). TELs represent the concentrations above which toxic biological effects occasionally occur in aquatic organisms, whereas PELs represent the concentrations above which toxic biological effects usually or frequently occur. Concentrations of cadmium, lead, and zinc exceeded the TELs but were less than the PELs in sediment samples from about one-half of the reservoirs and were less than the TELs in samples from the remaining reservoirs. Mercury concentrations were less than the TEL (information only available for four reservoirs). Silver was not detected in the bottom sediment fro

Draft Environmental Assessment for the Combat Support Training Complex, Tyndall Air Force Base, Florida.

DTIC Science & Technology

1989-07-25

nwdas Green Seaturtle PK E E 1,19 FISH Acipenser oxyrhynchus &esotoi Gulf Sturgeon SR SSC UR2 17,19 Mustela vison lutensis Florida Mink P - UR2 13...immediately dangerous to life and health (IDLH) with respect to respiratory irritation. This represents the maximum concentration from which one could...Threshold 0.004 mg/m3 ACGIH’ Median effective concentration 1-5 mg/m3 ACGIH Respiratory irritation Permissible exposure limit (PEL) 0.4 mg/m3

Assessment of noise in the airplane cabin environment.

PubMed

Zevitas, Christopher D; Spengler, John D; Jones, Byron; McNeely, Eileen; Coull, Brent; Cao, Xiaodong; Loo, Sin Ming; Hard, Anna-Kate; Allen, Joseph G

2018-03-15

To measure sound levels in the aircraft cabin during different phases of flight. Sound level was measured on 200 flights, representing six aircraft groups using continuous monitors. A linear mixed-effects model with random intercept was used to test for significant differences in mean sound level by aircraft model and across each flight phase as well as by flight phase, airplane type, measurement location and proximity to engine noise. Mean sound levels across all flight phases and aircraft groups ranged from 37.6 to >110 dB(A) with a median of 83.5 dB(A). Significant differences in noise levels were also observed based on proximity to the engines and between aircraft with fuselage- and wing mounted engines. Nine flights (4.5%) exceeded the recommended 8-h TWA exposure limit of 85 dB(A) by the NIOSH and ACGIH approach, three flights (1.5%) exceeded the 8-h TWA action level of 85 dB(A) by the OSHA approach, and none of the flights exceeded the 8-h TWA action level of 90 dB(A) by the OSHA PEL approach. Additional characterization studies, including personal noise dosimetry, are necessary to document accurate occupational exposures in the aircraft cabin environment and identify appropriate response actions. FAA should consider applying the more health-protective NIOSH/ACGIH occupational noise recommendations to the aircraft cabin environment.

Analysis and modeling of airborne BTEX concentrations from the Deepwater Horizon oil spill.

PubMed

Avens, Heather J; Unice, Ken M; Sahmel, Jennifer; Gross, Sherilyn A; Keenan, James J; Paustenbach, Dennis J

2011-09-01

Concerns have been raised about whether the Deepwater Horizon oil spill cleanup workers experienced adverse health effects from exposure to airborne benzene, toluene, ethylbenzene, and xylene (BTEX) which volatilized from surfaced oil. Thus, we analyzed the nearly 20 000 BTEX measurements of breathing zone air samples of offshore cleanup workers taken during the six months following the incident (made publicly available by British Petroleum). The measurements indicate that 99% of the measurements taken prior to capping the well were 32-, 510-, 360-, and 77-fold lower than the U.S. Occupational Safety and Health Administration's Permissible Exposure Limits (PELs) for BTEX, respectively. BTEX measurements did not decrease appreciably during the three months after the well was capped. Moreover, the magnitudes of these data were similar to measurements from ships not involved in oil slick remediation, suggesting that the BTEX measurements were primarily due to engine exhaust rather than the oil slick. To supplement the data analysis, two modeling approaches were employed to estimate airborne BTEX concentrations under a variety of conditions (e.g., oil slick thickness, wind velocity). The modeling results corroborated that BTEX concentrations from the oil were well below PELs and that the oil was not the primary contributor to the measured BTEX.

Exposure-related health effects of silver and silver compounds: a review.

PubMed

Drake, Pamela L; Hazelwood, Kyle J

2005-10-01

A critical review of studies examining exposures to the various forms of silver was conducted to determine if some silver species are more toxic than others. The impetus behind conducting this review is that several occupational exposure limits and guidelines exist for silver, but the values for each depend on the form of silver as well as the individual agency making the recommendations. For instance, the American Conference of Governmental Industrial Hygienists has established separate threshold limit values for metallic silver (0.1 mg/m3) and soluble compounds of silver (0.01 mg/m3). On the other hand, the permissible exposure limit (PEL) recommended by the Occupational Safety and Health Administration and the Mine Safety and Health Administration and the recommended exposure limit set by the National Institute for Occupational Safety and Health is 0.01 mg/m3 for all forms of silver. The adverse effects of chronic exposure to silver are a permanent bluish-gray discoloration of the skin (argyria) or eyes (argyrosis). Most studies discuss cases of argyria and argyrosis that have resulted primarily from exposure to the soluble forms of silver. Besides argyria and argyrosis, exposure to soluble silver compounds may produce other toxic effects, including liver and kidney damage, irritation of the eyes, skin, respiratory, and intestinal tract, and changes in blood cells. Metallic silver appears to pose minimal risk to health. The current occupational exposure limits do not reflect the apparent difference in toxicities between soluble and metallic silver; thus, many researchers have recommended that separate PELs be established.

INTERNATIONAL UNION OF OPERATING ENGINEERS NATIONAL HAZMAT PROGRAM - PORTER-CABLE CIRCULAR SAW OENHP: 2001-04, VERSION A

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

Unknown

2002-01-15

Florida International University's (FIU) Hemispheric Center for Environmental Technology (HCET) evaluated five saws for their effectiveness in cutting specially prepared fiberglass-reinforced plywood crates. These crates were built as surrogates for crates that presently hold radioactively contaminated glove boxes at the Department of Energy's (DOE) Los Alamos facility. The Porter-Cable circular saw was assessed on August 15-16, 2001 (Porter-Cable No.1 and Porter-Cable No.2, respectively). During the FIU test of efficacy, a team from the Operating Engineers National Hazmat Program (OENHP) evaluated the occupational safety and health issues associated with this technology. The Porter-Cable saw is a straightforward machine for cutting woodmore » of varying thickness. The blade is fully guarded with a fixed upper and a lower retractable guard. The lower guard retracts as the blade engages the work piece. The unit is operated with an on/off guarded trigger switch and is supported with a handgrip mounted near the front of the saw. The saw is equipped with a directional nozzle, which aims sawdust away from the operator and the line of cut. An optional vacuum system, attached to the directional nozzle, is used to remove and collect dust. During the demonstration of Porter-Cable No.1, personal noise sampling indicated that one worker was under and one was at the Occupational Safety and Health Administration's (OSHA) Action Level of 85 decibels (dBA) with time-weighted averages (TWA's) of 82.7 and 84.6 dBA, respectively. During the demonstration of Porter-Cable No.2, however, both workers did exceed the Action Level with TWA's of 89.7 and 90.0 dBA. These data are not entirely representative as they were gathered during a simulation and not at the actual worksite. Additional sampling should be conducted on-site, but the workers should wear hearing protection until it is determined that it is no longer necessary. The total nuisance dust sample for Porter-Cable No.1 was 3.53 milligrams per cubic meter (mg/m{sup 3}), which is lower than the OSHA Permissible Exposure Limit (PEL) of 15 mg/m{sup 3} and the American Conference of Governmental Industrial Hygienists' (ACGIH) Threshold Limit Value (TLV) of 10 mg/m{sup 3}. Porter-Cable No.2's nuisance dust results yielded a value of 22.05 mg/m{sup 3}, which is over the PEL and TLV. The fiber analysis for the first demonstration yielded 12.9 fibers per cubic centimeter (f/cc), which is much higher than the PEL of 1 f/cc. Galson Laboratories considered the fiber analysis for the second demonstration void due to the overloading of dust on the filter. Kickback, the sudden reaction to a pinched blade, is possible with this saw and could cause the saw to lift up and out of the work piece and toward the operator. Proper work position and firm control of the saw minimizes the potential for a sprain or strain. Care needs to be exercised to support the work piece properly and to not force the tool.« less

New isolates of carnation Italian ringspot virus differ from the original one by having replication-associated proteins with a typical tombusvirus-like N-terminus and by inducing peroxisome- rather than mitochondrion-derived multivesicular bodies.

PubMed

Koenig, Renate; Lesemann, Dietrich-Eckhardt; Pfeilstetter, Ernst

2009-01-01

Five new isolates of carnation Italian ringspot virus (CIRV) from cherry trees, Gypsophila and surface water differ from the original carnation isolate (CIRV-car) and also from Pelargonium necrotic spot virus (PelNSV) by having an ORF 1/ORF1-RT with a typical tombusvirus-like 5'end and by inducing the formation of peroxisome- rather than mitochondrion-derived multivesicular bodies (MVBs). This supports with natural isolates earlier conclusions reached by others with artificially produced hybrid viruses that the 5'end of ORF 1 determines from which organelle the MBVs will be derived. CIRV-car might have resulted from a natural recombination event with genome elements of a PelNSV-like virus.

The crystal structure of pectate lyase peli from soft rot pathogen Erwinia chrysanthemi in complex with its substrate.

PubMed

Creze, Christophe; Castang, Sandra; Derivery, Emmanuel; Haser, Richard; Hugouvieux-Cotte-Pattat, Nicole; Shevchik, Vladimir E; Gouet, Patrice

2008-06-27

The crystallographic structure of the family 3 polysaccharide lyase (PL-3) PelI from Erwinia chrysanthemi has been solved to 1.45 A resolution. It consists of an N-terminal domain harboring a fibronectin type III fold linked to a catalytic domain displaying a parallel beta-helix topology. The N-terminal domain is located away from the active site and is not involved in the catalytic process. After secretion in planta, the two domains are separated by E. chrysanthemi proteases. This event turns on the hypersensitive response of the host. The structure of the single catalytic domain determined to 2.1 A resolution shows that the domain separation unveils a "Velcro"-like motif of asparagines, which might be recognized by a plant receptor. The structure of PelI in complex with its substrate, a tetragalacturonate, has been solved to 2.3 A resolution. The sugar binds from subsites -2 to +2 in one monomer of the asymmetric unit, although it lies on subsites -1 to +3 in the other. These two "Michaelis complexes" have never been observed simultaneously before and are consistent with the dual mode of bond cleavage in this substrate. The bound sugar adopts a mixed 2(1) and 3(1) helical conformation similar to that reported in inactive mutants from families PL-1 and PL-10. However, our study suggests that the catalytic base in PelI is not a conventional arginine but a lysine as proposed in family PL-9.

Assessment of sediment toxicity and chemical concentrations in the San Diego Bay region, California, USA

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

Fairey, R.; Roberts, C.; Jacobi, M.

1998-08-01

Sediment quality within San Diego Bay, Mission Bay, and the Tijuana River Estuary of California was investigated as part of an ongoing statewide monitoring effort (Bay Protection and Toxic Cleanup Program). Study objectives were to determine the incidence, spatial patterns, and spatial extent of toxicity in sediments and porewater; the concentration and distribution of potentially toxic anthropogenic chemicals; and the relationships between toxicity and chemical concentrations. Rhepoxynius abronius survival bioassays, grain size, and total organic carbon analyses were performed on 350 sediment samples. Strongylocentrotus purpuratus development bioassays were performed on 164 pore-water samples. Toxicity was demonstrated throughout the San Diegomore » Bay region, with increased incidence and concordance occurring in areas of industrial and shipping activity. Trace metal and trace synthetic organic analyses were performed on 229 samples. Copper, zinc, mercury, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and chlordane were found to exceed ERM (effects range median) or PEL (probable effects level) sediment quality guidelines and were considered the six major chemicals or chemical groups of concern. Statistical analysis of the relationships between amphipod toxicity, bulk phase sediment chemistry, and physical parameters demonstrated few significant linear relationships. Significant differences in chemical levels were found between toxic and nontoxic responses using multivariate and univariate statistics. Potential sources of anthropogenic chemicals were discussed.« less

41 CFR 101-42.001 - Definitions of terms.

Code of Federal Regulations, 2010 CFR

2010-07-01

... systematically toxic by skin contact; (4) Has a permissible exposure limit (PEL) below 1000 p/m for gases and... occupational chemical dermatitis, which is any abnormality of the skin induced or aggravated by the work...

Paid Educational Leave

ERIC Educational Resources Information Center

Munro, John

1978-01-01

Discusses three reasons why the Canadian government is supportive of paid educational leave (PEL): the provision of a second chance, equal opportunity, and increased productivity. It also compares Canadian efforts in providing workers' education with those of other countries. (EM)

An ecological risk investigation of marine sediment from the northern Mediterranean coasts (Aegean Sea) using multiple methods of pollution determination.

PubMed

Tunca, Evren; Aydın, Mehmet; Şahin, Ülkü Alver

2018-03-01

The aim of this study is an assessment of metal pollution levels in Aegean Sea sediment. Sediment samples collected from 7 different locations (Yeniköy, Edremit, Ayvalık, Dikili, Aliağa, Hekimadası, and Ildır) along the northern Mediterranean region of Turkey were investigated for 11 elements (Cu, Fe, Zn, V, Cd, Ni, As, Pb, Mn, Co, and Cr). Graphite furnace atomic absorption spectrophotometry (GFAAS) and flame atomic absorption spectrophotometry (FAAS) were used for elemental analysis. The findings were evaluated with sediment assessment methods by taking two different values as a reference and then investigating the adverse biological effects of elemental profiles on living organisms. Pb, Mn, As, Cd, and Cr concentrations were within a moderate to significant range in terms of contamination factor [Formula: see text]), albeit varying according to reference and location. The most problematic region and elements regarding the enrichment factor (EF) was Ayvalık and As, Ni, Cu, Pb, Co, and Cd. However, according to the EF, the anthropogenic effect was not at an alarming level. This was further supported by the results of the geoaccumulation index (Igeo). The findings of the modified degree of contamination (mC d ) and the pollution load index (PLI) suggested that the accumulation was greatest in Ayvalık, and the least in Hekimadası and Ildır. The location with the highest elemental total toxic unit (ΣTU) was Edremit. The effect of the existing element profile on organisms was 21% in this location when the mean effect range-median quotient (m-ERM-q) was considered. As and Ni concentrations in all stations were found to be higher than threshold effect level (TEL) and Effect Range Low (ERL). Ni levels in Edremit exceeded the probable effect level (PEL) and Effect Range Median (ERM). Toxic unit (TU) values of these two elements in all stations ranged from 59.30 to 80.43%.

Case cluster of pneumoconiosis at a coal slag processing facility.

PubMed

Fagan, Kathleen M; Cropsey, Erin B; Armstrong, Jenna L

2015-05-01

During an inspection by the Occupational Safety and Health Administration (OSHA) of a small coal slag processing plant with 12 current workers, four cases of pneumoconiosis were identified among former workers. The OSHA investigation consisted of industrial hygiene sampling, a review of medical records, and case interviews. Some personal sampling measurements exceeded the OSHA Permissible Exposure Limit (PEL) for total dust exposures of 15 mg/m(3), and the measured respirable silica exposure of 0.043 mg/m(3), although below OSHA's current PEL for respirable dust containing silica, was above the American Conference of Governmental Industrial Hygienists' Threshold Limit Value (TLV). Chest x-rays for all four workers identified small opacities consistent with pneumoconiosis. This is the first known report of lung disease in workers processing coal slag and raises concerns for workers exposed to coal slag dust. © 2015 Wiley Periodicals, Inc.

Controlling potential barrier height by changing V-shaped pit size and the effect on optical and electrical properties for InGaN/GaN based light-emitting diodes

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

Okada, Narihito, E-mail: nokada@yamaguchi-u.ac.jp; Kashihara, Hiroyuki; Sugimoto, Kohei

2015-01-14

The internal quantum efficiency (IQE) of InGaN/GaN multiple quantum wells (MQWs) with blue light emission was improved by inserting an InGaN/GaN superlattice (SL) beneath the MQWs. While the SL technique is useful for improving the light-emitting diode (LED) performance, its effectiveness from a multilateral point of view requires investigation. V-shaped pits (V-pits), which generate a potential barrier and screen the effect of the threading dislocation, are one of the candidates for increasing the light emission efficiency of LEDs exceptionally. In this research, we investigated the relationship between the V-pit and SL and revealed that the V-pit diameter is strongly correlatedmore » with the IQE by changing the number of SL periods. Using scanning near-field optical microscopy and photoluminescence measurements, we demonstrated the distinct presence of the potential barrier formed by the V-pits around the dislocations. The relationship between the V-pit and the number of SL periods resulted in changing the potential barrier height, which is related to the V-pit diameter determined by the number of SL periods. In addition, we made an attempt to insert pit expansion layers (PELs) composed of combination of SL and middle temperature grown GaN layer instead of only SL structure. As a result of the evaluation of LEDs using SL or PEL, the EL intensity was strongly related to pit diameter regardless of the structures to form the V-pits. In addition, it was clear that larger V-pits reduce the efficiency droop, which is considered to be suppression of the carrier loss at high injection current.« less

Single-coil properties and concentration effects for polyelectrolyte-like wormlike micelles: a Monte Carlo study

NASA Astrophysics Data System (ADS)

Cannavacciuolo, Luigi; Skov Pedersen, Jan; Schurtenberger, Peter

2002-03-01

Results of an extensive Monte Carlo (MC) study on both single and many semiflexible charged chains with excluded volume (EV) are summarized. The model employed has been tailored to mimic wormlike micelles in solution. Simulations have been performed at different ionic strengths of added salt, charge densities, chain lengths and volume fractions Φ, covering the dilute to concentrated regime. At infinite dilution the scattering functions can be fitted by the same fitting functions as for uncharged semiflexible chains with EV, provided that an electrostatic contribution bel is added to the bare Kuhn length. The scaling of bel is found to be more complex than the Odijk-Skolnick-Fixman predictions, and qualitatively compatible with more recent variational calculations. Universality in the scaling of the radius of gyration is found if all lengths are rescaled by the total Kuhn length. At finite concentrations, the simple model used is able to reproduce the structural peak in the scattering function S(q) observed in many experiments, as well as other properties of polyelectrolytes (PELs) in solution. Universal behaviour of the forward scattering S(0) is established after a rescaling of Φ. MC data are found to be in very good agreement with experimental scattering measurements with equilibrium PELs, which are giant wormlike micelles formed in mixtures of nonionic and ionic surfactants in dilute aqueous solution, with added salt.

Combining contamination indexes, sediment quality guidelines and multivariate data analysis for metal pollution assessment in marine sediments of Cienfuegos Bay, Cuba.

PubMed

Peña-Icart, Mirella; Pereira-Filho, Edenir Rodrigues; Lopes Fialho, Lucimar; Nóbrega, Joaquim A; Alonso-Hernández, Carlos; Bolaños-Alvarez, Yoelvis; Pomares-Alfonso, Mario S

2017-02-01

The purpose of the present work was to combine several tools for assessing metal pollution in marine sediments from Cienfuegos Bay. Fourteen surface sediments collected in 2013 were evaluated. Concentrations of As, Cu, Ni, Zn and V decreased respect to those previous reported. The metal contamination was spatially distributed in the north and south parts of the bay. According to the contamination factor (CF) enrichment factor (EF) and index of geoaccumulation (I geo ), Cd and Cu were classified in that order as the most contaminated elements in most sediment. Comparison of the total metal concentrations with the threshold (TELs) and probable (PELs) effect levels in sediment quality guidelines suggested a more worrisome situation for Cu, of which concentrations were occasional associated with adverse biological effects in thirteen sediments, followed by Ni in nine sediments; while adverse effects were rarely associated with Cd. Probably, Cu could be considered as the most dangerous in the whole bay because it was classified in the high contamination levels by all indexes and, simultaneously, associated to occasional adverse effects in most samples. Despite the bioavailability was partially evaluated with the HCl method, the low extraction of Ni (<3% in all samples) and Cu (<55%, except sample 3) and the relative high extraction of Cd (50% or more, except sample 14) could be considered as an attenuating (Ni and Cu) or increasing (Cd) factor in the risk assessment of those element. Copyright © 2016. Published by Elsevier Ltd.

LADTAG Progress 2010 and Plans for 2011 and Provisional PELs from Lavage and Blood Data

NASA Technical Reports Server (NTRS)

James, John T.

2010-01-01

This viewgraph presentation reviews the Lunar Airborne Dust Toxicity Assessment Group (LADTAG) plans and progress for 2010 and 2011. Provisional Permissible Exposure Limits (PPELs) from lavage fluid and blood data are also presented.

Development of a decision support system to manage contamination in marine ecosystems.

PubMed

Dagnino, A; Viarengo, A

2014-01-01

In recent years, contamination and its interaction with climate-change variables have been recognized as critical stressors in coastal areas, emphasizing the need for a standardized framework encompassing chemical and biological data into risk indices to support decision-making. We therefore developed an innovative, expert decision support system (Exp-DSS) for the management of contamination in marine coastal ecosystems. The Exp-DSS has two main applications: (i) to determine environmental risk and biological vulnerability in contaminated sites; and (ii) to support the management of waters and sediments by assessing the risk due to the exposure of biota to these matrices. The Exp-DSS evaluates chemical data, both as single compounds and as total toxic pressure of the mixture, to compare concentrations to effect-based thresholds (TELs and PELs). Sites are then placed into three categories of contamination: uncontaminated, mildly contaminated, and highly contaminated. In highly contaminated sites, effects on high-level ecotoxicological endpoints (i.e. survival and reproduction) are used to determine risk at the organism-population level, while ecological parameters (i.e. alterations in community structure and ecosystem functions) are considered for assessing effects on biodiversity. Changes in sublethal biomarkers are utilized to assess the stress level of the organisms in mildly contaminated sites. In Triad studies, chemical concentrations, ecotoxicological high-level effects, and ecological data are combined to determine the level of environmental risk in highly contaminated sites; chemical concentration and ecotoxicological sublethal effects are evaluated to determine biological vulnerability in mildly contaminated sites. The Exp-DSS was applied to data from the literature about sediment quality in estuarine areas of Spain, and ranked risks related to exposure to contaminated sediments from high risk (Huelva estuary) to mild risk (Guadalquivir estuary and Bay of Cadiz). A spreadsheet-based version of the Exp-DSS is available at the MEECE and DiSIT web sites (www.meece.eu and www.disit.unipmn.it). © 2013 Elsevier B.V. All rights reserved.

Assessing occupational mercury exposures and behaviours of artisanal and small-scale gold miners in Burkina Faso using passive mercury vapour badges.

PubMed

Black, Paleah; Richard, Myrianne; Rossin, Ricardo; Telmer, Kevin

2017-01-01

Artisanal and small-scale gold mining (ASGM) is a crucial economic activity in Burkina Faso, however it is associated with significant mercury exposure and health concerns. The aim of the present study was to assess the level of mercury (Hg) vapour exposures and occupational behaviours at a representative site using Hg vapour monitor badges and questionnaires. To our knowledge this is the first time that personal exposure to Hg vapour during ASGM activities has been reported. The study population were ASGM workers who completed a questionnaire (n=100) or participated with an occupational exposure assessment using commercially available passive Hg vapour samplers (n=44). Occupational exposure to Hg was high during open-air burn events with a time weighted average (TWA) exposure of 7026±6857µg/m 3 for burners, and 1412±2870µg/m 3 for bystanders. Most (82%) of the people present at the burn exceeded the Permissible Exposure Limit (PEL) of 100µg/m 3 , and 11% exceeded the level considered to be Immediately Dangerous to Life and Health (IDLH) of 10,000µg/m 3 . Even control workers who were not present at the burn exceeded the PEL (24%), likely due to legacy Hg contamination producing latent Hg releases to the atmosphere. Similarly, 86% of the miners at the burn and 59% of control workers had an 8-h TWA that exceeded the Recommended Exposures Limit (REL). Several occupational behaviours that may contribute to Hg exposures were documented. This study corroborates previous studies suggesting that Hg exposure during amalgam burning is very high, and demonstrates the plausibility of using passive vapour monitoring badges rather than costly and logistically difficult biomonitoring methods. Mercury reduction and elimination interventions are strongly needed to reduce Hg exposure in ASGM communities, particularly as countries come into compliance with the Minamata Convention. Copyright © 2016 Elsevier Inc. All rights reserved.

Expression patterns of cell wall-modifying genes from banana during fruit ripening and in relationship with finger drop

PubMed Central

Mbéguié-A-Mbéguié, D.; Hubert, O.; Baurens, F. C.; Matsumoto, T.; Chillet, M.; Fils-Lycaon, B.; Sidibé-Bocs, S.

2009-01-01

Few molecular studies have been devoted to the finger drop process that occurs during banana fruit ripening. Recent studies revealed the involvement of changes in the properties of cell wall polysaccharides in the pedicel rupture area. In this study, the expression of cell-wall modifying genes was monitored in peel tissue during post-harvest ripening of Cavendish banana fruit, at median area (control zone) and compared with that in the pedicel rupture area (drop zone). To this end, three pectin methylesterase (PME) and seven xyloglucan endotransglycosylase/hydrolase (XTH) genes were isolated. The accumulation of their mRNAs and those of polygalaturonase, expansin, and pectate lyase genes already isolated from banana were examined. During post-harvest ripening, transcripts of all genes were detected in both zones, but accumulated differentially. MaPME1, MaPG1, and MaXTH4 mRNA levels did not change in either zone. Levels of MaPME3 and MaPG3 mRNAs increased greatly only in the control zone and at the late ripening stages. For other genes, the main molecular changes occurred 1–4 d after ripening induction. MaPME2, MaPEL1, MaPEL2, MaPG4, MaXTH6, MaXTH8, MaXTH9, MaEXP1, MaEXP4, and MaEXP5 accumulated highly in the drop zone, contrary to MaXTH3 and MaXTH5, and MaEXP2 throughout ripening. For MaPG2, MaXET1, and MaXET2 genes, high accumulation in the drop zone was transient. The transcriptional data obtained from all genes examined suggested that finger drop and peel softening involved similar mechanisms. These findings also led to the proposal of a sequence of molecular events leading to finger drop and to suggest some candidates. PMID:19357434

The Elephant in the Room: Biomedical Challenges for Long Duration Lunar Habitation

NASA Technical Reports Server (NTRS)

Logan, James S.

2009-01-01

This slide presentation reviews 4 biomedical challenges that are involved in long duration lunar habitation: dust, radiation, hypogravity and synergistic effects. The first two of these challenges are reviewed with more in-depth information. The dangers of dust relate to the particle deposition in the lungs. The dangers of radiation are related to the permissible exposure limit (PEL) and the Risk of Exposure Induced Death (REID), a statistical approach pegged to a single radiation effect: Death from cancer directly attributable to the exposure. There has been a realization that radiation is more harmful than predicted. This is demonstrated by showing the change in the recommended career dose limits, have changed between 1989 and 2000.

78 FR 56273 - Occupational Exposure to Respirable Crystalline Silica

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-12

... (b) Definitions (c) Permissible Exposure Limit (PEL) (d) Exposure Assessment (e) Regulated Areas and...) Communication of Respirable Crystalline Silica Hazards to Employees (j) Recordkeeping (k) Dates XVII. References... Maryland) well recognized for its macroeconomic modeling--to run its LIFT (Long-term Interindustry...

Planning and environment linkages program : a guide to measuring progress in linking transportation planning and environmental analysis

DOT National Transportation Integrated Search

2009-12-01

Transportation agencies use a variety of metrics to document progress toward achieving specific goals and objectives. This guide, developed by Federal Highway Administration (FHWA) Planning and Environmental Linkages (PEL) program, is intended to hel...

Spatial distribution and ecological risk assessment of heavy metal on surface sediment in west part of Java Sea

NASA Astrophysics Data System (ADS)

Effendi, Hefni; Wardiatno, Yusli; Kawaroe, Mujizat; Mursalin; Fauzia Lestari, Dea

2017-01-01

The surface sediments were identified from west part of Java Sea to evaluate spatial distribution and ecological risk potential of heavy metals (Hg, As, Cd, Cr, Cu, Pb, Zn and Ni). The samples were taken from surface sediment (<0.5 m) in 26 m up to 80 m water depth with Eikman grab. The average material composition on sediment samples were clay (9.86%), sand (8.57%) and mud sand (81.57%). The analysis showed that Pb (11.2%), Cd (49.7%), and Ni (59.5%) exceeded of Probably Effect Level (PEL). Base on ecological risk analysis, {{Cd }}≤ft( {E_r^i:300.64} \\right) and {{Cr }}≤ft( {E_r^i:0.02} \\right) were categorized to high risk and low risk criteria. The ecological risk potential sequences of this study were Cd>Hg>Pb>Ni>Cu>As>Zn>Cr. Furthermore, the result of multivariate statistical analysis shows that correlation among heavy metals (As/Ni, Cd/Ni, and Cu/Zn) and heavy metals with Risk Index (Cd/Ri and Ni/Ri) had positive correlation in significance level p<0.05. Total variance of analysis factor was 80.04% and developed into 3 factors (eigenvalues >1). On the cluster analysis, Cd, Ni, Pb were identified as fairly high contaminations level (cluster 1), Hg as moderate contamination level (cluster 2) and Cu, Zn, Cr with lower contamination level (cluster 3).

A new airborne geophysical platform and its application in the Princess Elizabeth Land during CHINARE 32 and 33 in East Antarctica

NASA Astrophysics Data System (ADS)

Cui, Xiangbin; Sun, Bo; Guo, Jingxue; Tang, Xueyuan; Greenbaum, Jamin; Lindzey, Laura; Habbal, Feras; Young, Duncan

2017-04-01

The ice thickness, subglacial topography and bedrock conditions of Princess Elizabeth Land (PEL) in central East Antarctic Ice Sheet (EAIS) are still unknown due to lack of direct geophysical measurements. This prevents our understanding of the ice sheet dynamics, subglacial morphology and climate evolution in the region. According to recent results from remote sensing results, it's very likely that there's a large, previously undiscovered subglacial lake and subglacial drainage networks existing beneath the ice sheet in PEL with possible subglacial canyons extend over a distance of 1100 km from inland to coast. But there's no direct measurements to identify them yet. China deployed its first fixed-wing airplane named Snow Eagle 601 and implemented airborne geophysical investigation in PEL during the 32nd and 33rd Chinese National Antarctic Research Expeditions (CHINARE 32 and 33, 2015/16 and 2016/17). The HiCARS deep ice-penetrating radar system and other instruments including GT-2A gravimeter, CS-3 magnetometer, laser altimeter, GPS and camera, were installed in the airplane to measure the ice sheet and subglacial conditions, as well as bedrock geology and tectonic. The field campaign was built beside Russian airfield (ZGN) near Zhongshan Station. During CHINARE 32, the airborne surveying grid was designed as radial lines from ZGN so as to investigate the region as large as possible, and total flight lines are 32 000 km. During the CHINARE 33, airborne survey will pay attention to the subglacial lake and subglacal canyons. Here, we introduce the Snow Eagle airborne geophysical platform firstly. Then, we present some preliminary results from CHINARE 32 and CHINARE 33.

A Tool for Model-Based Generation of Scenario-driven Electric Power Load Profiles

NASA Technical Reports Server (NTRS)

Rozek, Matthew L.; Donahue, Kenneth M.; Ingham, Michel D.; Kaderka, Justin D.

2015-01-01

Power consumption during all phases of spacecraft flight is of great interest to the aerospace community. As a result, significant analysis effort is exerted to understand the rates of electrical energy generation and consumption under many operational scenarios of the system. Previously, no standard tool existed for creating and maintaining a power equipment list (PEL) of spacecraft components that consume power, and no standard tool existed for generating power load profiles based on this PEL information during mission design phases. This paper presents the Scenario Power Load Analysis Tool (SPLAT) as a model-based systems engineering tool aiming to solve those problems. SPLAT is a plugin for MagicDraw (No Magic, Inc.) that aids in creating and maintaining a PEL, and also generates a power and temporal variable constraint set, in Maple language syntax, based on specified operational scenarios. The constraint set can be solved in Maple to show electric load profiles (i.e. power consumption from loads over time). SPLAT creates these load profiles from three modeled inputs: 1) a list of system components and their respective power modes, 2) a decomposition hierarchy of the system into these components, and 3) the specification of at least one scenario, which consists of temporal constraints on component power modes. In order to demonstrate how this information is represented in a system model, a notional example of a spacecraft planetary flyby is introduced. This example is also used to explain the overall functionality of SPLAT, and how this is used to generate electric power load profiles. Lastly, a cursory review of the usage of SPLAT on the Cold Atom Laboratory project is presented to show how the tool was used in an actual space hardware design application.

Sedimentology, geochemistry, pollution status and ecological risk assessment of some heavy metals in surficial sediments of an Egyptian lagoon connecting to the Mediterranean Sea.

PubMed

El-Said, Ghada F; Draz, Suzanne E O; El-Sadaawy, Manal M; Moneer, Abeer A

2014-01-01

Spatial distribution of heavy metals (Co, Cu, Ni, Cr, Mn, Zn and Fe) was studied on Lake Edku's surface sediments in relation to sedimentology and geochemistry characteristics and their contamination status on the ecological system. Lake Edku's sediments were dominated by sandy silt and silty sand textures and were enriched with carbonate content (9.83-58.46%). Iron and manganese were the most abundant heavy metals with ranges of 1.69 to 8.06 mg g(-1) and 0.88 to 3.27 mg g(-1), respectively. Cobalt and nickel showed a harmonic distribution along the studied sediments. The results were interpreted by the statistical means. The heavy metal pollution status and their ecological risk in Lake Edku was evaluated using the sediment quality guidelines and the contamination assessment methods (geoaccumulation, pollution load and potential ecological risk indices, enrichment factor, contamination degree as well as effect range median (ERM) and probable effect level (PEL) quotients). Amongst the determined heavy metals, zinc had the most ecological risk. Overall, the heavy metals in surface sediments showed ecological effect range from moderate to considerable risk, specially, in the stations in front of the seawater and in drain sources that had the highest toxic priority.

Evaluation of potential toxicity from co-exposure to three CNS depressants (toluene, ethylbenzene, and xylene) under resting and working conditions using PBPK modeling.

PubMed

Dennison, James E; Bigelow, Philip L; Mumtaz, Moiz M; Andersen, Melvin E; Dobrev, Ivan D; Yang, Raymond S H

2005-03-01

Under OSHA and American Conference of Governmental Industrial Hygienists (ACGIH) guidelines, the mixture formula (unity calculation) provides a method for evaluating exposures to mixtures of chemicals that cause similar toxicities. According to the formula, if exposures are reduced in proportion to the number of chemicals and their respective exposure limits, the overall exposure is acceptable. This approach assumes that responses are additive, which is not the case when pharmacokinetic interactions occur. To determine the validity of the additivity assumption, we performed unity calculations for a variety of exposures to toluene, ethylbenzene, and/or xylene using the concentration of each chemical in blood in the calculation instead of the inhaled concentration. The blood concentrations were predicted using a validated physiologically based pharmacokinetic (PBPK) model to allow exploration of a variety of exposure scenarios. In addition, the Occupational Safety and Health Administration and ACGIH occupational exposure limits were largely based on studies of humans or animals that were resting during exposure. The PBPK model was also used to determine the increased concentration of chemicals in the blood when employees were exercising or performing manual work. At rest, a modest overexposure occurs due to pharmacokinetic interactions when exposure is equal to levels where a unity calculation is 1.0 based on threshold limit values (TLVs). Under work load, however, internal exposure was 87%higher than provided by the TLVs. When exposures were controlled by a unity calculation based on permissible exposure limits (PELs), internal exposure was 2.9 and 4.6 times the exposures at the TLVs at rest and workload, respectively. If exposure was equal to PELs outright, internal exposure was 12.5 and 16 times the exposure at the TLVs at rest and workload, respectively. These analyses indicate the importance of (1) selecting appropriate exposure limits, (2) performing unity calculations, and (3) considering the effect of work load on internal doses, and they illustrate the utility of PBPK modeling in occupational health risk assessment.

Radiation dose to workers due to the inhalation of dust during granite fabrication.

PubMed

Zwack, L M; McCarthy, W B; Stewart, J H; McCarthy, J F; Allen, J G

2014-03-01

There has been very little research conducted to determine internal radiation doses resulting from worker exposure to ionising radiation in granite fabrication shops. To address this issue, we estimated the effective radiation dose of granite workers in US fabrication shops who were exposed to the maximum respirable dust and silica concentrations allowed under current US regulations, and also to concentrations reported in the literature. Radiation doses were calculated using standard methods developed by the International Commission on Radiological Protection. The calculated internal doses were very low, and below both US occupational standards (50 mSv yr(-1)) and limits applicable to the general public (1 mSv yr(-1)). Workers exposed to respirable granite dust concentrations at the US Occupational Safety and Health Administration (OSHA) respirable dust permissible exposure limit (PEL) of 5 mg m(-3) over a full year had an estimated radiation dose of 0.062 mSv yr(-1). Workers exposed to respirable granite dust concentrations at the OSHA silica PEL and at the American Conference of Governmental Industrial Hygienists Threshold Limit Value for a full year had expected radiation doses of 0.007 mSv yr(-1) and 0.002 mSv yr(-1), respectively. Using data from studies of respirable granite dust and silica concentrations measured in granite fabrication shops, we calculated median expected radiation doses that ranged from <0.001 to 0.101 mSv yr(-1).

24 CFR 990.160 - Overview of calculating formula expenses.

Code of Federal Regulations, 2013 CFR

2013-04-01

... formula expense. The formula expense of any one project is the sum of the project's PEL and the UEL... 24 Housing and Urban Development 4 2013-04-01 2013-04-01 false Overview of calculating formula... URBAN DEVELOPMENT THE PUBLIC HOUSING OPERATING FUND PROGRAM Calculating Formula Expenses § 990.160...

24 CFR 990.160 - Overview of calculating formula expenses.

Code of Federal Regulations, 2014 CFR

2014-04-01

... formula expense. The formula expense of any one project is the sum of the project's PEL and the UEL... 24 Housing and Urban Development 4 2014-04-01 2014-04-01 false Overview of calculating formula... URBAN DEVELOPMENT THE PUBLIC HOUSING OPERATING FUND PROGRAM Calculating Formula Expenses § 990.160...

24 CFR 990.160 - Overview of calculating formula expenses.

Code of Federal Regulations, 2012 CFR

2012-04-01

... formula expense. The formula expense of any one project is the sum of the project's PEL and the UEL... 24 Housing and Urban Development 4 2012-04-01 2012-04-01 false Overview of calculating formula... URBAN DEVELOPMENT THE PUBLIC HOUSING OPERATING FUND PROGRAM Calculating Formula Expenses § 990.160...

24 CFR 990.160 - Overview of calculating formula expenses.

Code of Federal Regulations, 2011 CFR

2011-04-01

... formula expense. The formula expense of any one project is the sum of the project's PEL and the UEL... 24 Housing and Urban Development 4 2011-04-01 2011-04-01 false Overview of calculating formula... URBAN DEVELOPMENT THE PUBLIC HOUSING OPERATING FUND PROGRAM Calculating Formula Expenses § 990.160...

24 CFR 990.160 - Overview of calculating formula expenses.

Code of Federal Regulations, 2010 CFR

2010-04-01

... formula expense. The formula expense of any one project is the sum of the project's PEL and the UEL... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Overview of calculating formula... URBAN DEVELOPMENT THE PUBLIC HOUSING OPERATING FUND PROGRAM Calculating Formula Expenses § 990.160...

Tracing the X-Ray Trail

MedlinePlus

... finalizado el examen, el radiólogo, médico entrenado para la lectura de imágenes para diagnóstico, examina las películas. El radiólogo dicta un informe que describe las técnicas utilizadas para adquirir la imagen, el motivo del examen, antecedentes relevantes del ...

Evidence Report: Risk of Cardiovascular Disease and Other Degenerative Tissue Effects from Radiation Exposure

NASA Technical Reports Server (NTRS)

Patel, Zarana; Huff, Janice; Saha, Janapriya; Wang, Minli; Blattnig, Steve; Wu, Honglu; Cucinotta, Francis

2015-01-01

Occupational radiation exposure from the space environment may result in non-cancer or non-CNS degenerative tissue diseases, such as cardiovascular disease, cataracts, and respiratory or digestive diseases. However, the magnitude of influence and mechanisms of action of radiation leading to these diseases are not well characterized. Radiation and synergistic effects of radiation cause DNA damage, persistent oxidative stress, chronic inflammation, and accelerated tissue aging and degeneration, which may lead to acute or chronic disease of susceptible organ tissues. In particular, cardiovascular pathologies such as atherosclerosis are of major concern following gamma-ray exposure. This provides evidence for possible degenerative tissue effects following exposures to ionizing radiation in the form of the GCR or SPEs expected during long-duration spaceflight. However, the existence of low dose thresholds and dose-rate and radiation quality effects, as well as mechanisms and major risk pathways, are not well-characterized. Degenerative disease risks are difficult to assess because multiple factors, including radiation, are believed to play a role in the etiology of the diseases. As additional evidence is pointing to lower, space-relevant thresholds for these degenerative effects, particularly for cardiovascular disease, additional research with cell and animal studies is required to quantify the magnitude of this risk, understand mechanisms, and determine if additional protection strategies are required.The NASA PEL (Permissive Exposure Limit)s for cataract and cardiovascular risks are based on existing human epidemiology data. Although animal and clinical astronaut data show a significant increase in cataracts following exposure and a reassessment of atomic bomb (A-bomb) data suggests an increase in cardiovascular disease from radiation exposure, additional research is required to fully understand and quantify these adverse outcomes at lower doses (less than 0.5 gray (SI unit for ionizing radiation dosage, i.e. one joule of radiation energy per one kilogram of matter)) to facilitate risk prediction. This risk has considerable uncertainty associated with it, and no acceptable model for projecting degenerative tissue risk is currently available. In particular, risk factors such as obesity, alcohol, and tobacco use can act as confounding factors that contribute to the large uncertainties. The PELs could be violated under certain scenarios, including following a large SPE (solar proton event) or long-term GCR (galactic cosmic ray) exposure. Specifically, for a Mars mission, the accumulated dose is sufficiently high that epidemiology data and preliminary risk estimates suggest a significant risk for cardiovascular disease. Ongoing research in this area is intended to provide the evidence base for accurate risk quantification to determine criticality for extended duration missions. Data specific to the space radiation environment must be compiled to quantify the magnitude of this risk to decrease the uncertainty in current PELs and to determine if additional protection strategies are required. New research results could lead to estimates of cumulative radiation risk from CNS and degenerative tissue diseases that, when combined with the cancer risk, may have major negative impacts on mission design, costs, schedule, and crew selection. The current report amends an earlier report (Human Research Program Requirements Document, HRP-47052, Rev. C, dated Jan 2009) in order to provide an update of evidence since 2009.

Forging an American Grand Strategy: Securing a Path Through a Complex Future

DTIC Science & Technology

2013-10-01

rounded U.S. representative. Generals Petrae - us and H. R. McMaster both went to civilian schools (Princeton and University of North Carolina Cha- pel...Joint Chiefs of Staff U.S. Army General Martin Dempsey graduated from the National War College, as did Air Force Chief of Staff General Norton

46 CFR 197.530 - Persons other than employees.

Code of Federal Regulations, 2012 CFR

2012-10-01

... STANDARDS GENERAL PROVISIONS Benzene § 197.530 Persons other than employees. (a) Before a nonemployee (other than Federal, state, and local government personnel) engages in a benzene operation on a vessel in which the person is likely to be exposed to benzene in excess of the PELs, that person must certify that...

46 CFR 197.530 - Persons other than employees.

Code of Federal Regulations, 2010 CFR

2010-10-01

... STANDARDS GENERAL PROVISIONS Benzene § 197.530 Persons other than employees. (a) Before a nonemployee (other than Federal, state, and local government personnel) engages in a benzene operation on a vessel in which the person is likely to be exposed to benzene in excess of the PELs, that person must certify that...

46 CFR 197.530 - Persons other than employees.

Code of Federal Regulations, 2013 CFR

2013-10-01

... STANDARDS GENERAL PROVISIONS Benzene § 197.530 Persons other than employees. (a) Before a nonemployee (other than Federal, state, and local government personnel) engages in a benzene operation on a vessel in which the person is likely to be exposed to benzene in excess of the PELs, that person must certify that...

46 CFR 197.530 - Persons other than employees.

Code of Federal Regulations, 2011 CFR

2011-10-01

... STANDARDS GENERAL PROVISIONS Benzene § 197.530 Persons other than employees. (a) Before a nonemployee (other than Federal, state, and local government personnel) engages in a benzene operation on a vessel in which the person is likely to be exposed to benzene in excess of the PELs, that person must certify that...

46 CFR 197.530 - Persons other than employees.

Code of Federal Regulations, 2014 CFR

2014-10-01

... STANDARDS GENERAL PROVISIONS Benzene § 197.530 Persons other than employees. (a) Before a nonemployee (other than Federal, state, and local government personnel) engages in a benzene operation on a vessel in which the person is likely to be exposed to benzene in excess of the PELs, that person must certify that...

24 CFR 990.190 - Other formula expenses (add-ons).

Code of Federal Regulations, 2010 CFR

2010-04-01

... operating subsidy is determined to be zero based on the formula is still eligible to receive operating... formula expenses (add-ons). In addition to calculating operating subsidy based on the PEL and UEL, a PHA's... receive an amount for PILOT in accordance with section 6(d) of the 1937 Act, based on its cooperation...

24 CFR 990.190 - Other formula expenses (add-ons).

Code of Federal Regulations, 2011 CFR

2011-04-01

... operating subsidy is determined to be zero based on the formula is still eligible to receive operating... formula expenses (add-ons). In addition to calculating operating subsidy based on the PEL and UEL, a PHA's... receive an amount for PILOT in accordance with section 6(d) of the 1937 Act, based on its cooperation...

Integration of the blaNDM-1 carbapenemase gene into Proteus genomic island 1 (PGI1-PmPEL) in a Proteus mirabilis clinical isolate.

PubMed

Girlich, Delphine; Dortet, Laurent; Poirel, Laurent; Nordmann, Patrice

2015-01-01

To decipher the mechanisms and their associated genetic determinants responsible for β-lactam resistance in a Proteus mirabilis clinical isolate. The entire genetic structure surrounding the β-lactam resistance genes was characterized by PCR, gene walking and DNA sequencing. Genes encoding the carbapenemase NDM-1 and the ESBL VEB-6 were located in a 38.5 kb MDR structure, which itself was inserted into a new variant of the Proteus genomic island 1 (PGI1). This new PGI1-PmPEL variant of 64.4 kb was chromosomally located, as an external circular form in the P. mirabilis isolate, suggesting potential mobility. This is the first known description of the bla(NDM-1) gene in a genomic island structure, which might further enhance the spread of the bla(NDM-1) carbapenemase gene among enteric pathogens. © The Author 2014. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

PCR and restriction fragment length polymorphism of a pel gene as a tool to identify Erwinia carotovora in relation to potato diseases.

PubMed Central

Darrasse, A; Priou, S; Kotoujansky, A; Bertheau, Y

1994-01-01

Using a sequenced pectate lyase-encoding gene (pel gene), we developed a PCR test for Erwinia carotovora. A set of primers allowed the amplification of a 434-bp fragment in E. carotovora strains. Among the 89 E. carotovora strains tested, only the Erwinia carotovora subsp. betavasculorum strains were not detected. A restriction fragment length polymorphism (RFLP) study was undertaken on the amplified fragment with seven endonucleases. The Sau3AI digestion pattern specifically identified the Erwinia carotovora subsp. atroseptica strains, and the whole set of data identified the Erwinia carotovora subsp. wasabiae strains. However, Erwinia carotovora subsp. carotovora and Erwinia carotovora subsp. odorifera could not be separated. Phenetic and phylogenic analyses of RFLP results showed E. carotovora subsp. atroseptica as a homogeneous group while E. carotovora subsp. carotovora and E. carotovora subsp. odorifera strains exhibited a genetic diversity that may result from a nonmonophyletic origin. The use of RFLP on amplified fragments in epidemiology and for diagnosis is discussed. Images PMID:7912502

Influence of sample preparation on the transformation of low-density to high-density amorphous ice: An explanation based on the potential energy landscape

NASA Astrophysics Data System (ADS)

Giovambattista, Nicolas; Starr, Francis W.; Poole, Peter H.

2017-07-01

Experiments and computer simulations of the transformations of amorphous ices display different behaviors depending on sample preparation methods and on the rates of change of temperature and pressure to which samples are subjected. In addition to these factors, simulation results also depend strongly on the chosen water model. Using computer simulations of the ST2 water model, we study how the sharpness of the compression-induced transition from low-density amorphous ice (LDA) to high-density amorphous ice (HDA) is influenced by the preparation of LDA. By studying LDA samples prepared using widely different procedures, we find that the sharpness of the LDA-to-HDA transformation is correlated with the depth of the initial LDA sample in the potential energy landscape (PEL), as characterized by the inherent structure energy. Our results show that the complex phenomenology of the amorphous ices reported in experiments and computer simulations can be understood and predicted in a unified way from knowledge of the PEL of the system.

PELS (Planetary Environmental Liquid Simulator): a new type of simulation facility to study extraterrestrial aqueous environments.

PubMed

Martin, Derek; Cockell, Charles S

2015-02-01

Investigations of other planetary bodies, including Mars and icy moons such as Enceladus and Europa, show that they may have hosted aqueous environments in the past and may do so even today. Therefore, a major challenge in astrobiology is to build facilities that will allow us to study the geochemistry and habitability of these extraterrestrial environments. Here, we describe a simulation facility (PELS: Planetary Environmental Liquid Simulator) with the capability for liquid input and output that allows for the study of such environments. The facility, containing six separate sample vessels, allows for statistical replication of samples. Control of pressure, gas composition, UV irradiation conditions, and temperature allows for the precise replication of aqueous conditions, including subzero brines under martian atmospheric conditions. A sample acquisition system allows for the collection of both liquid and solid samples from within the chamber without breaking the atmospheric conditions, enabling detailed studies of the geochemical evolution and habitability of past and present extraterrestrial environments. The facility we describe represents a new frontier in planetary simulation-continuous flow-through simulation of extraterrestrial aqueous environments.

Determination of exposure to respirable quartz in the stone crushing units at Azendarian-West of Iran.

PubMed

Bahrami, Abdul Rahman; Golbabai, Faridah; Mahjub, Hossien; Qorbani, Farshid; Aliabadi, Mohsan; Barqi, Mohamadali

2008-08-01

The purpose of this study is to describe the personal exposure to respirable dust and quartz and in stone crushing units located at west of Iran. A size of 40 personal samples and 40 stationary samples were obtained and analysis was done by X-ray diffraction (XRD). The results of personal sampling were shown the concentrations of respirable dust exposure level in workers of process, hopper and drivers were 1.90, 2.22, 1.41 times greater than Occupational Safety and Health Administration permissible exposure limit (OSHA PEL). The average value of total dust and respirable dust emission from stationary sources was 9.46 mg/m(3), 1.24 mg/m(3) respectively, showing that 13.8 % of total dust is respirable. The efficiency of local exhaust ventilation (LEV) to control of particles inside of industrial units was greater than 99%. It is concluded from this research the particulate generated from stone crushing activities contain a significant amount of respirable particle. The amount of free silica in stone quartz is 85 to 97 percent that emission of particles effect to health workers. LEV has important effect in the removal of silica particles in stone crushing units. The worker of hoppers still exposed to silica more than standard limits.

Effects of conversion of mangroves into gei wai ponds on sediment heavy metals accumulation in tidal flat estuary, South China

NASA Astrophysics Data System (ADS)

Li, R.; Qiu, G.; Chai, M.; Li, R.

2017-12-01

Gei wai ponds act as important component in mangrove ecosystem, but the conversion of mangroves into gei wai ponds and its ecological function on heavy metal accumulation is still not clear. The study quantified the sediment heavy metal concentration and speciation in gei wai pond, Avicennia marina marsh and mudflat in Futian mangrove wetlands, South China. The results showed that gei wai pond acidified the sediment and reduced its fertility due to reduced pH, electronic conductivity (EC) and total organic carbon (TOC) compared to A. marina marsh and mudflat. The concentrations of Cd, Cu, Zn and Pb at all depth in gei wai pond sediment were also lower than other sites, indicating reduced storage function on heavy metals. Multiple analysis implied that heavy metals in all sites could be attributed to anthropogenic sources, with Cr as natural and anthropogenic sources in gei wai pond. Gei wai pond sediment had lower heavy metal pollution based on multiple evaluation methods, including potential ecological risk coefficient (Eir), potential ecological risk index (RI), geo-accumulation index (Igeo), mean PEL quotients (m-PEL-q), pollution load index (PLI), mean ERM quotients (m-ERM-q) and total toxic unit (∑TU). Heavy metal speciation analysis indicated that gei wai pond improved the conversion from the immobilized Cd and Cr to the mobilized fraction. SEM-AVS analysis indicated no adverse toxicity occurred in all sites, and the role of TOC in relieving sediment heavy metal toxicity of gei wai pond is limited.

First laboratory high-temperature emissivity measurements of Venus analog measurements in the near-infrared atmospheric windows

NASA Astrophysics Data System (ADS)

Helbert, J.; Maturilli, A.; Ferrari, S.; Dyar, M. D.; Smrekar, S. E.

2014-12-01

The permanent cloud cover of Venus prohibits observation of the surface with traditional imaging techniques over most of the visible spectral range. Venus' CO2 atmosphere is transparent exclusively in small spectral windows near 1 μm. The Visible and Infrared Thermal Imaging Spectrometer (VIRTIS) team on the European Space Agency Venus-Express mission have recently used these windows successfully to map the southern hemisphere from orbit. VIRTIS is showing variations in surface brightness, which can be interpreted as variations in surface emissivity. Deriving surface composition from these variations is a challenging task. Comparison with laboratory analogue spectra are complicated by the fact that Venus has an average surface temperature of 730K. Mineral crystal structures and their resultant spectral signatures are notably affected by temperature, therefore any interpretations based on room temperature laboratory spectra database can be misleading. In order to support the interpretation of near-infrared data from Venus we have started an extensive measurement campaign at the Planetary Emissivity Laboratory (PEL, Institute of Planetary Research of the German Aerospace Center, Berlin). The PEL facility, which is unique in the world, allows emission measurements covering the 1 to 2 μm wavelength range at sample temperatures of up to 770K. Conciliating the expected emissivity variation between felsic and mafic minerals with Venera and VEGA geochemical data we have started with a set of five analog samples. This set includes basalt, gneiss, granodiorite, anorthosite and hematite, thus covering the range of mineralogies. Preliminary results show significant spectral contrast, thus allowing different samples to be distinguished with only 5 spectral points and validating the use of thermal emissivity for investigating composition. This unique new dataset from PEL not only allows interpretation of the Venus Express VIRTIS data but also provide a baseline for considering new instrument designs for future Venus missions.

New Alloys for Electroformed Replicated X-Ray Optics

NASA Technical Reports Server (NTRS)

Engelhaupt, D.; Ramsey, B. D.; ODell, S. L.; Jones, W. D.; Russell, J. K.

2000-01-01

The process of electroforming x-ray mirror shells off a superpolished mandrel has been widely used. The recently launched XMM mission is a good example of this, containing 174 such mirror shells of diameters ranging from 0.3-0.7 m and thicknesses of 0.47-1.07 mm. To continue to utilize this technique for the next generation of x-ray observatories, where ever-larger collecting areas will be required within the constraints of tight weight budgets, demands that new alloys be developed that can withstand the large stresses imposed on very thin shells by the replication and handling processes. Towards this end, we began a development program in late 1997 to produce a high-strength alloy suitable for electroforming very thin high-resolution x-ray optics. The requirements for this task are quite severe; not only must the electroformed deposit be very strong, it must also have extremely low residual stresses to prevent serious figure distortions in large thin-walled shells. Further, the electroforming must be performed at near room temperature, as large temperature changes will modify the figure of the mandrel, in an environment that is not corrosive for the mandrel. The figure of merit for the strength of the electroformed deposit is its Precision Elastic Limit (PEL). This is a measure of permanent strain, at the few parts per million level, under applied stress. Pure nickel is very ductile and will permanently deform, at the parts-per-million level under loads of a few x 10(exp 7) Pa. These stresses are easily exceeded when thin-walled shells (150 micron thick) are replicated. Our goal was to develop an alloy an order of magnitude stronger than this. We will present the results of our development program, showing the evolution of our plating baths through to our present 'glassy' nickel alloy that satisfies the goals above. For each we will show the electroforming characteristics of the bath and the PEL measurements for the resulting alloys. We estimate the ultimate limit on shell thickness and mass for x-ray mirrors produced in these baths.

Characterization of heavy metal concentrations in the sediments of three freshwater rivers in Huludao City, Northeast China.

PubMed

Zheng, Na; Wang, Qichao; Liang, Zhongzhu; Zheng, Dongmei

2008-07-01

Wuli River, Cishan River, and Lianshan River are three freshwater rivers flowing through Huludao City, in a region of northeast China strongly affected by industrialization. Contamination assessment has never been conducted in a comprehensive way. For the first time, the contamination of three rivers impacted by different sources in the same city was compared. This work investigated the distribution and sources of Hg, Pb, Cd, Zn and Cu in the surface sediments of Wuli River, Cishan River, and Lianshan River, and assessed heavy metal toxicity risk with the application of two different sets of Sediment Quality Guideline (SQG) indices (effect range low/effect range median values, ERL/ERM; and threshold effect level/probable effect level, TEL/PEL). Furthermore, this study used a toxic unit approach to compare and gauge the individual and combined metal contamination for Hg, Pb, Cd, Zn and Cu. Results showed that Hg contamination in the sediments of Wuli River originated from previous sediment contamination of the chlor-alkali producing industry, and Pb, Cd, Zn and Cu contamination was mainly derived from atmospheric deposition and unknown small pollution sources. Heavy metal contamination to Cishan River sediments was mainly derived from Huludao Zinc Plant, while atmospheric deposition, sewage wastewater and unknown small pollution were the primary sources for Lianshan River. The potential acute toxicity in sediment of Wuli River may be primarily due to Hg contamination. Hg is the major toxicity contributor, accounting for 53.3-93.2%, 7.9-54.9% to total toxicity in Wuli River and Lianshan River, respectively, followed by Cd. In Cishan River, Cd is the major sediment toxicity contributor, however, accounting for 63.2-66.9% of total toxicity.

The effect of airborne lead particle size on worker blood-lead levels: an empirical study of battery workers.

PubMed

Hodgkins, D G; Robins, T G; Hinkamp, D L; Schork, M A; Levine, S P; Krebs, W H

1991-12-01

Theoretical models and experimental data suggest that the particle size distribution of lead aerosols should affect the lead dose absorbed by exposed workers. In the present study, 44 workers in five major operations in a high-volume, lead-acid battery plant were studied for the influence of lead aerosol size on lead-in-blood (PbB) levels. A multiple linear regression analysis based on particle size assumptions made in the model used by the Occupational Safety and Health Administration to help select the permissible exposure level (PEL) for lead showed no improvement in prediction of PbB over that already present without any consideration of particle size. The use of the American Conference of Governmental Industrial Hygienists (ACGIH) regional size-selective criteria also failed to improve the prediction of PbB. However, when deposition models developed by Heyder et al were used in which the lead aerosol was separated into alveolar and extra-alveolar fractions, corresponding to what is considered respirable and ingestible lead, the coefficient of determination (R2) associated with the fractionated lead particulate increased approximately 25% over that attributable to only the total lead concentration. In addition, the deposition model, which closely matched the ACGIH reference worker criteria, resulted in ratios of the coefficients for the respirable to ingestible lead contributions to PbB that appeared to agree with experimental data, suggesting approximately a 10 to 1 ratio in absorption efficiency of the lung versus the gastrointestinal tract.

An adaptive DPCM algorithm for predicting contours in NTSC composite video signals

NASA Astrophysics Data System (ADS)

Cox, N. R.

An adaptive DPCM algorithm is proposed for encoding digitized National Television Systems Committee (NTSC) color video signals. This algorithm essentially predicts picture contours in the composite signal without resorting to component separation. The contour parameters (slope thresholds) are optimized using four 'typical' television frames that have been sampled at three times the color subcarrier frequency. Three variations of the basic predictor are simulated and compared quantitatively with three non-adaptive predictors of similar complexity. By incorporating a dual-word-length coder and buffer memory, high quality color pictures can be encoded at 4.0 bits/pel or 42.95 Mbit/s. The effect of channel error propagation is also investigated.

The Role of Physical Education Lessons and Recesses in School Lifestyle of Adolescents

ERIC Educational Resources Information Center

Frömel, Karel; Svozil, Zbynek; Chmelík, František; Jakubec, Lukáš; Groffik, Dorota

2016-01-01

Background: This study investigates school lifestyle among adolescents in terms of physical activity (PA) structure: (1) adolescents participating in a physical education lesson (PEL) versus (2) aggregate recess time exceeding 60 minutes. Methods: The research was conducted in 24 secondary schools in the Czech Republic (boys N = 208, girls N =…

A colorimetric sensor array for identification of toxic gases below permissible exposure limits†

PubMed Central

Feng, Liang; Musto, Christopher J.; Kemling, Jonathan W.; Lim, Sung H.; Suslick, Kenneth S.

2010-01-01

A colorimetric sensor array has been developed for the rapid and sensitive detection of 20 toxic industrial chemicals (TICs) at their PELs (permissible exposure limits). The color changes in an array of chemically responsive nanoporous pigments provide facile identification of the TICs with an error rate below 0.7%. PMID:20221484

Monitoring heavy metal concentrations in the sediments of the Moskva and Oka River system- Results of the Volga-Rhine-Project

NASA Astrophysics Data System (ADS)

Andresen, Höpke

2010-05-01

In the course of the Volga-Rhine-Project sediment, water and pore water samples were collected on the Volga as well as the Moskva and Oka river systems. The sampling area discussed here is located south east of the city of Moscow. Sediment samples were taken along the Moskva River between Moscow and the city of Kolomna, which is approximately 100 km to the southeast of Moscow and in the Oka River close to the confluence with the Moskva River (Kolomna). The first sampling campaign in this region took place in 1993, followed by further sampling in 1997 and 2007. For evaluation of sediment quality classification systems are often used. The geo-accumulation index proposed by Mueller (1979) is a classification system which consists of seven classes given by the following expression: I = log2×Cn- geo 1.5×Bn Where Cn = measured concentration; Bn = background value (Turekian & Wedepol 1961) of element n and 1.5 = background matrix correction factor. The geo-accumulation index consists of seven grades (0-6) which indicate the enrichment of an element compared to the background value. These grades range from 'not polluted' to 'very strongly polluted'. Another possibility to express sediment contamination is to evaluate the effects on the ecosystem. The lowest effect level (LEL) gives the concentrations of the heavy metals in sediment below which no effect on the majority of the sediment dwelling organisms is expected. The probable effect level (PEL) represents the concentration of heavy metals above which the organisms frequently will show adverse effects. Both of these approaches were used to evaluate the results of the Volga-Rhine-Project. In the last two decades the concentrations of heavy metals in the sediments decreased by up to 60%. In 1993 sediments revealed high concentrations of several heavy metals such as chromium, cadmium, lead, zinc, arsenic, nickel and cobalt, whereas in 2007 only two sediment samples were classified as 'very strongly polluted' regarding lead and cadmium concentrations. Additionally six other sediment samples were found to be 'strongly polluted' with cadmium, zinc and lead, respectively. Using the ecotoxicological approach on the sediments, chromium, cadmium and zinc are above the PEL, whereas the content of lead exceeds the LEL. Thus, these metals may still cause toxic effects on the fresh water system. Although the input of heavy metals into the river systems has clearly decreased during the last 20 years, there are still some locations where high concentrations of heavy metals are found, suggesting point sources. Especially cadmium still shows significantly higher concentrations than the background value in the entire sampling area. There are even two sampling points where the cadmium concentrations reach approximately 100x the background value. To determine the temporal variation of the heavy metal input, sediment cores were taken. Heavy metal concentrations increase with depth in the cores and show a maximum at a depth of about 35-40 cm. Some part of this increase may be a result of early diagenesis as well as a result of reduced heavy metal input. The nature of the decline of the heavy metal concentrations is still in progress. Despite all the improvements achieved in environmental protection in Russia, still some problems have to be addressed. Especially in urban areas like the Moscow region the number and the size of illegal dump sites is increasing dramatically, leading to strong inputs of heavy metals and other pollutants into the river systems, with consequences for the sensitive eco systems.

Polycyclic aromatic hydrocarbons (PAHs) and alkylated PAHs in the coastal seawater, surface sediment and oyster from Dalian, Northeast China.

PubMed

Hong, Wen-Jun; Jia, Hongliang; Li, Yi-Fan; Sun, Yeqing; Liu, Xianjie; Wang, Luo

2016-06-01

A total of 46 polycyclic aromatic hydrocarbons (PAHs, 21 parent and 25 alkylated) were determined in seawater, surface sediment and oyster from coastal area of Dalian, North China. The concentration of Σ46PAHs in seawater, sediment, and oyster were 136-621 ng/L, 172-4700 ng/g dry weight (dw) and 60.0-129 ng/g wet weight (ww) in winter, and 65.0-1130 ng/L, 71.1-1090 ng/g dw and 72.8-216 ng/g ww in summer, respectively. High PAH levels were found in industrial area both in winter and summer. Selected PAH levels in sediments were compared with Sediments Quality Guidelines (ERM-ERL, TEL-PEL indexes) for evaluation probable toxic effects on marine organism and the results indicate that surface sediment from all sampling sites have a low to medium ecotoxicological risk. Daily intake of PAHs via oyster as seafood by humans were estimated and the results indicated that oyster intake would not pose a health risk to humans even 30 days after a oil spill accident near by. Water-sediment exchange analysis showed that, both in winter and summer, the fluxes for most high molecular weight PAHs were from seawater to sediment, while for low molecular weight PAHs, an equilibrium was reached between seawater and sediment. Copyright © 2016 Elsevier Inc. All rights reserved.

What can 35 years and over 700,000 measurements tell us about noise exposure in the mining industry?

PubMed Central

Roberts, Benjamin; Sun, Kan; Neitzel, Richard L.

2017-01-01

Objective To analyze over 700,000 cross-sectional measurements from the Mine Safety and Health Administration (MHSA) and develop statistical models to predict noise exposure for a worker. Design Descriptive statistics were used to summarize the data. Two linear regression models were used to predict noise exposure based on MSHA permissible exposure limit (PEL) and action level (AL) respectively. Two-fold cross validation was used to compare the exposure estimates from the models to actual measurements in the hold out data. The mean difference and t-statistic was calculated for each job title to determine if the model exposure predictions were significantly different from the actual data. Study Sample Measurements were acquired from MSHA through a Freedom of Information Act request. Results From 1979 to 2014 the average noise measurement has decreased. Measurements taken before the implementation of MSHA’s revised noise regulation in 2000 were on average 4.5 dBA higher than after the law came in to effect. Both models produced mean exposure predictions that were less than 1 dBA different compared to the holdout data. Conclusion Overall noise levels in mines have been decreasing. However, this decrease has not been uniform across all mining sectors. The exposure predictions from the model will be useful to help predict hearing loss in workers from the mining industry. PMID:27871188

Modeling Respiratory Toxicity of Authentic Lunar Dust

NASA Technical Reports Server (NTRS)

Santana, Patricia A.; James, John T.; Lam, Chiu-Wing

2010-01-01

The lunar expeditions of the Apollo operations from the 60 s and early 70 s have generated awareness about lunar dust exposures and their implication towards future lunar explorations. Critical analyses on the reports from the Apollo crew members suggest that lunar dust is a mild respiratory and ocular irritant. Currently, NASA s space toxicology group is functioning with the Lunar Airborne Dust Toxicity Assessment Group (LADTAG) and the National Institute for Occupational Safety and Health (NIOSH) to investigate and examine toxic effects to the respiratory system of rats in order to establish permissible exposure levels (PELs) for human exposure to lunar dust. In collaboration with the space toxicology group, LADTAG and NIOSH the goal of the present research is to analyze dose-response curves from rat exposures seven and twenty-eight days after intrapharyngeal instillations, and model the response using BenchMark Dose Software (BMDS) from the Environmental Protection Agency (EPA). Via this analysis, the relative toxicities of three types of Apollo 14 lunar dust samples and two control dust samples, titanium dioxide (TiO2) and quartz will be determined. This will be executed for several toxicity endpoints such as cell counts and biochemical markers in bronchoaveolar lavage fluid (BALF) harvested from the rats.

Ototoxic occupational exposures for a stock car racing team: I. Noise surveys.

PubMed

Van Campen, Luann E; Morata, Thais; Kardous, Chucri A; Gwin, Kristin; Wallingford, Kenneth M; Dallaire, Jacques; Alvarez, Frank J

2005-08-01

The National Institute for Occupational Safety and Health (NIOSH) surveyed noise exposure for a professional stock car team at their race shop and during two races at one racetrack. At the team's shop, area sound pressure levels (SPLs) were measured for various work tasks. Equivalent levels (Leqs) ranged from 58 to 104 decibels, A-weighted (dBA). Personal noise dosimetry was conducted for at least one employee for each job description in race car assembly (n = 9). The Occupational Safety and Health Administration (OSHA) permissible exposure limit (PEL) of 90 dBA for an 8-hour, 5-dB exchange rate time-weighted average (TWA) was never exceeded, but in two instances values exceeded OSHA's action level of 85 dBA for hearing conservation implementation. The NIOSH recommended exposure limit (REL) of 85 dBA for a 3-dB exchange rate Leq was exceeded for five of the measured jobs. During the races, SPLs averaged above 100 dBA in the pit area where cars undergo adjustments/refueling, both before and during the race. Peak levels reached 140 dB SPL. NIOSH REL was exceeded for every personal noise dosimetry measurement. Recommendations for hearing protection and communication are presented.

Finding Uncertainties that Cause the Age Dependence of Dose Limits to Be Immature

NASA Technical Reports Server (NTRS)

Cucinotta, Francis A.

2007-01-01

Space radiation permissible exposure limits (PEL) are intended to set acceptable levels of cancer risks, and avoid any clinical significant non-cancer effects. The 1989 recommendation of the National Council of Radiation Protection and Measurements (NCRP) recommended a strong age dependence of dose limits that departed drastically from the then mature 1970 dose limits recommendations from the National Academy of Science, which were independent of age. In 2000, the NCRP recommended revised limits that showed a similar trend of risk with age to the 1989 report. In this model, the cancer risk per Sv varies by more than 2-fold for ages between 30- and 50-yr. Therefore for galactic cosmic rays exposure, astronaut age has a larger influence on risk then radiation shielding mass or material composition, vehicle propulsion method, or position in the solar cycle. For considering the control of mission costs and resources, the possibility of using astronaut age as a trade variable in mission design could be considered. However, the uncertainties in describing the age dependence on risk have not been fully explored. We discuss biological factors that influence the age dependence of radiation risks, including susceptibility, expression and latency, and radiation quality. These factors depend not only on the individual s age, but also their genetic sensitivity and interaction with other environmental factors. Epidemiological data is limited in describing the age dependence on risk. The 2005, BEIR VII report recommends an age dependence for cancer risk attributable solely to the life-table disagreeing strongly with the NCRP model. However, BEIR VII also noted the limited power of human data for concomitantly describing both age and age after exposure dependences of cancer risks. Many experimental studies have shown that high LET radiation (e.g., high charge and energy (HZE) nuclei and neutrons) display reduced latency compared to low LET radiation, suggesting distinct biological factors are important. We discuss potential molecular mechanisms that would influence the age dependence of radiation risks. A probability distribution function for the uncertainties in age-dependence of risk models is described and predictions for Mars missions discussed. Our report suggests that theoretical considerations based on new experimental studies are needed to ensure the correct age dependence in space radiation risk models and the resulting Astronaut PEL.

A description of chloride cell and kidney tubule alterations in the flatfish Solea senegalensis exposed to moderately contaminated sediments from the Sado estuary (Portugal)

NASA Astrophysics Data System (ADS)

Costa, Pedro M.; Caeiro, Sandra; Diniz, Mário S.; Lobo, Jorge; Martins, Marta; Ferreira, Ana M.; Caetano, Miguel; Vale, Carlos; DelValls, T. Ángel; Costa, M. Helena

2010-11-01

The effects of sediment-bound contaminants on kidney and gill chloride cells were surveyed in juvenile Solea senegalensis exposed to fresh sediments collected from three distinct sites of the Sado Estuary (Portugal) in a 28-day laboratorial assay. Sediments were analyzed for metallic contaminants, polycyclic aromatic hydrocarbons and organochlorines as well as for total organic matter, redox potential and fine fraction. The potential for causing adverse biological effects of each surveyed sediment was assessed by comparison of contaminant levels to available guidelines for coastal sediments, namely the Threshold Effects Level ( TEL) and the Probable Effects Level ( PEL). The Sediment Quality Guideline Quotient indices ( SQGQ) were calculated to compare the overall contamination levels of the three stations. A qualitative approach was employed to analyze the histo/cytopathological traits in gill chloride cells and body kidney of fish exposed to each tested sediment for 0, 14 and 28 days. The results showed that sediment contamination can be considered low to moderate and that the least contaminated sediment (from a reference site, with the lowest SQGQ) caused lesser changes in the surveyed organs. However, the most contaminated sediment (by both metallic and organic xenobiotics, with highest SQGQ) was neither responsible for the highest mortality nor for the most pronounced lesions. Exposure to the sediment presenting an intermediate SQGQ, essentially contaminated by organic compounds, caused the highest mortality (48%) and the most severe damage to kidneys, up to full renal necrosis. Chloride cell alterations were similar in fish exposed to the two most contaminated sediments and consisted of a pronounced cellular hypertrophy, likely involving fluid retention and loss of mitochondria. It can be concluded that sediment contamination considered to be low or moderate may be responsible for severe injury to cells and parenchyma involved in the maintenance of osmotic balance, contributing for the high mortality levels observed. The results suggest that sediment-bound organic contaminants such as PAHs (polycyclic aromatic hydrocarbons) and PCBs (polychlorinated biphenyls) may be very toxic to the analyzed organs, especially the kidney, even when present in low-risk concentrations.

Paid Educational Leave and Self-Directed Learning: Implications for Legislation on the Learning Leave Scheme in South Korea

ERIC Educational Resources Information Center

Oh, Jeong Rok; Park, Cho Hyun; Jo, Sung Jun

2016-01-01

Purpose: The purposes of this study are to explore paid educational leave (PEL), self-directed learning (SDL) and the relationship between them; and to identify the implications for legislation on the learning leave scheme in South Korea. Design/Methodology/Approach: The research method of the study is a literature review. Articles were identified…

Low Temperature Cure Powder Coatings

DTIC Science & Technology

2013-05-01

operations Minimize worker exposure to VOCs, HAPs, and hexavalent chrome Passed objective AF Engr Qual Plan = Air Force Engineer Quality Plan MIL-PRF...Inconclusive • Inconclusive • Not applicable (N/A) • Passed criteria Reduction of hexavalent chromium use • Passed objective Reduction of hazardous...compliance. The implementation of the OSHA Final Rule designating the permissible exposure limit (PEL) for hexavalent chromium is a significant

Pathology of Kaposi’s Sarcoma-Associated Herpesvirus Infection

PubMed Central

Fukumoto, Hitomi; Kanno, Takayuki; Hasegawa, Hideki; Katano, Harutaka

2011-01-01

Kaposi’s sarcoma-associated herpesvirus (KSHV; human herpesvirus 8) is a human herpesvirus, classified as a gamma-herpesvirus. KSHV is detected in Kaposi’s sarcoma (KS), primary effusion lymphoma (PEL), and some cases of multicentric Castleman’s disease (MCD). Similar to other herpes viruses, there are two phases of infection, latent and lytic. In KSHV-associated malignancies such as KS and PEL, KSHV latently infects almost all tumor cells. Quantitative PCR analysis revealed that each tumor cell contains one copy of KSHV in KS lesions. The oncogenesis by KSHV has remained unclear. Latency-associated nuclear antigen (LANA)-1 plays an important role in the pathogenesis of KSHV-associated malignancies through inhibition of apoptosis and maintenance of latency. Because all KSHV-infected cells express LANA-1, LANA-1 immunohistochemistry is a useful tool for diagnosis of KSHV infection. KSHV encodes some homologs of cellular proteins including cell-cycle regulators, cytokines, and chemokines, such as cyclin D, G-protein-coupled protein, interleukin-6, and macrophage inflammatory protein-1 and -2. These viral proteins mimic or disrupt host cytokine signals, resulting in microenvironments amenable to tumor growth. Lytic infection is frequently seen in MCD tissues, suggesting a different pathogenesis from KS and lymphoma. PMID:21904536

Role of defective Oct-2 and OCA-B expression in immunoglobulin production and Kaposi's sarcoma-associated herpesvirus lytic reactivation in primary effusion lymphoma.

PubMed

Di Bartolo, Daniel L; Hyjek, Elizabeth; Keller, Shannon; Guasparri, Ilaria; Deng, Hongyu; Sun, Ren; Chadburn, Amy; Knowles, Daniel M; Cesarman, Ethel

2009-05-01

Primary effusion lymphoma (PEL) is a distinct type of B-cell non-Hodgkin lymphoma characterized by the presence of Kaposi's sarcoma-associated herpesvirus (KSHV/human herpesvirus 8). Despite having a genotype and gene expression signature of highly differentiated B cells, PEL does not usually express surface or cytoplasmic immunoglobulin (Ig). We show the lack of Oct-2 and OCA-B transcription factors to be responsible, at least in part, for this defect in Ig production. Like Ig genes, ORF50, the key regulator of the switch from latency to lytic reactivation, contains an octamer motif within its promoter. We therefore examined the impact of Oct-2 and OCA-B on ORF50 activation. The binding of Oct-1 to the ORF50 promoter has been shown to significantly enhance ORF50 transactivation. We found that Oct-2, on the other hand, inhibited ORF50 expression and consequently lytic reactivation by competing with Oct-1 for the octamer motif in the ORF50 promoter. Our data suggest that Oct-2 downregulation in infected cells would be favorable to KSHV in allowing for efficient viral reactivation.

Surface Tension Mediated Under-Water Adhesion of Rigid Spheres on Soft, Charged Surfaces

NASA Astrophysics Data System (ADS)

Sinha, Shayandev; Das, Siddhartha

2015-11-01

Understanding the phenomenon of surface-tension-mediated under-water adhesion is necessary for studying a plethora of physiological and technical phenomena, such as the uptake of bacteria or nanoparticle by cells, attachment of virus on bacterial surfaces, biofouling on large ocean vessels and marine devices, etc. This adhesion phenomenon becomes highly non-trivial in case the soft surface where the adhesion occurs is also charged. Here we propose a theory for analyzing such an under-water adhesion of a rigid sphere on a soft, charged surface, represented by a grafted polyelectrolyte layer (PEL). We develop a model based on the minimization of free energy that, in addition to considering the elastic and the surface-tension-mediated adhesion energies, also accounts for the PEL electric double layer (EDL) induced electrostatic energies. We show that in the presence of surface charges, adhesion gets enhanced. This can be explained by the fact that the increase in the elastic energy is better balanced by the lowering of the EDL energy associated with the adhesion process. The entire behaviour is further dictated by the surface tension components that govern the adhesion energy.

Anthranilate deteriorates the structure of Pseudomonas aeruginosa biofilms and antagonizes the biofilm-enhancing indole effect.

PubMed

Kim, Soo-Kyoung; Park, Ha-Young; Lee, Joon-Hee

2015-04-01

Anthranilate and indole are alternative degradation products of tryptophan, depending on the bacterial species. While indole enhances the biofilm formation of Pseudomonas aeruginosa, we found that anthranilate, the tryptophan degradation product of P. aeruginosa, had an opposite effect on P. aeruginosa biofilm formation, in which anthranilate deteriorated the mushroom structure of biofilm. The anthranilate effect on biofilm formation was differentially exerted depending on the developmental stage and the presence of shear force. Anthranilate slightly accelerated the initial attachment of P. aeruginosa at the early stage of biofilm development and appeared to build more biofilm without shear force. But anthranilate weakened the biofilm structure in the late stage, deteriorating the mushroom structure of biofilms with shear force to make a flat biofilm. To investigate the interplay of anthranilate with indole in biofilm formation, biofilms were cotreated with anthranilate and indole, and the results showed that anthranilate antagonized the biofilm-enhancing effect of indole. Anthranilate was able to deteriorate the preformed biofilm. The effect of anthranilate and indole on biofilm formation was quorum sensing independent. AntR, a regulator of anthranilate-degrading metabolism was synergistically activated by cotreatment with anthranilate and indole, suggesting that indole might enhance biofilm formation by facilitating the degradation of anthranilate. Anthranilate slightly but significantly affected the cyclic diguaniylate (c-di-GMP) level and transcription of major extracellular polysaccharide (Psl, Pel, and alginate) operons. These results suggest that anthranilate may be a promising antibiofilm agent and antagonize the effect of indole on P. aeruginosa biofilm formation. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Space Radiation and Exploration - Information for the Augustine Committee Review

NASA Technical Reports Server (NTRS)

Cucinotta, Francis; Semones, Edward; Kim, Myung-Hee; Jackson, Lori

2009-01-01

Space radiation presents significant health risks including mortality for Exploration missions: a) Galactic cosmic ray (GCR) heavy ions are distinct from radiation that occurs on Earth leading to different biological impacts. b) Large uncertainties in GCR risk projections impact ability to design and assess mitigation approaches and select crew. c) Solar Proton Events (SPEs) require new operational and shielding approaches and new biological data on risks. Risk estimates are changing as new scientific knowledge is gained: a) Research on biological effects of space radiation show qualitative and quantitative differences with X- or gamma-rays. b) Expert recommendations and regulatory policy are changing. c) New knowledge leads to changes in estimates for the number of days in space to stay below Permissible Exposure Limits (PELS).

Targeting of Prostate Cancer with Hyaluronan-Binding Proteins

DTIC Science & Technology

2005-06-01

16). Briefly, bovine nasal cartilage (Pel-Freez, Rogers, AR) was shredded with a Sure-Form blade (Stanley). extracted overnight with 4 M guanidine... nasal cartilage by affinity chromatography on hyaluronan- E Sepharose. As shown in Fig. 1, Metastatin consisted of two molecular C 40 factions as...biotinylated 490 pg/ml.) was isolated from the medium of rat fibrosarcoma cells grown tachvplesin (Fig. IB). However, this interaction was

The Regulation of Endogenous Glutamate and GABA Release from In Vitro Preparations of Rat Striatum

DTIC Science & Technology

1997-09-19

polyethylenimine (PEl) in 50 mM sodium borate pH 7.4 overnight. then washed with PBS pH 7.4 twice before 2 m1 of NS-media were added to each well...Celsius in 95% oxygen and 5% CO2 . 2. Fetal striatum dissection and neuron culture preparation Female Sprague-Dawley rats. 18-day pregnant. under 2.5

Estimating NOA Health Risks from Selected Construction Activities at the Calaveras Dam Replacement Project (CDRP)

NASA Astrophysics Data System (ADS)

Hernandez, D. W.

2012-12-01

The CDRP is a major construction project involving up to 400 workers using heavy earth moving equipment, blasting, drilling, rock crushing, and other techniques designed to move 7 million yards of earth. Much of this material is composed of serpentinite, blueschist, and other rocks that contain chrysotile, crocidolite, actinolite, tremolite, and Libby-class amphiboles. To date, over 1,000 personal, work area, and emission inventory related samples have been collected and analyzed by NIOSH 7400, NIOSH 7402, and CARB-AHERA methodology. Data indicate that various CDRP construction activities have the potential to generate significant mineral fibers and structures that could represent elevated on site and off site health risks. This presentation will review the Contractors air monitoring program for this major project, followed by a discussion of predictive methods to evaluate potential onsite and offsite risks. Ultimately, the data are used for planning control strategies designed to achieve a Project Action Level of 0.01 f/cc (one tenth the Cal/OSHA PEL) and risk-based offsite target levels.

Chemical speciation and ecological risk assessment of arsenic in marine sediments from Izmir Bay (Eastern Aegean Sea).

PubMed

Gonul, L T

2015-12-01

Total arsenic, arsenic(III) and (V), Fe, and Mn were measured in 17 surface sediment samples from Izmir Bay. The concentrations and ecological risk of As were characterized in the sediment affected by urban and agricultural activities. Total As ranged from 8.87 to 28.3 μg g(-1) dry weight (96.5-99.9 % as inorganic As). Distribution of total As and total As/Fe followed a different trend in sediments at all sampling sites. Arsenite (As(III)) was the most dominant form followed by As(V), while organic arsenic represented a minor constituent (0.03 to 3.49 %). The highest concentration of total As was observed at Gediz River estuary and exceeded lower threshold value (threshold effects level (TEL)). Due to the biological reduction of As(V) and abundance of Fe (oxyhydr)oxides in the sediments, most inorganic As in the Izmir Bay was present as As(III). Besides, the levels of As were >TEL and

Nonlinear Optical Properties and Subpicosecond Dynamics of Excitons and Electron-Hole Plasmas in Multiple Quantum Well Structures.

DTIC Science & Technology

1987-12-01

estimated from 10 S Ee 0.916 O(Pe) (7)rs Vel / y 7 where ve is the valley degeneracy factor, and $ is an anisotropy factor 10 1/6 sin- [(I Pe)l 124O...nergy, an potential, (2V,), have been deduced from the bro adening parameters of the jt structure The growth parameters with n-i p-i 498 having

Scalable Planning and Learning for Multiagent POMDPs

DTIC Science & Technology

2015-01-01

Scalable Planning and Learning for Multiagent POMDPs Christopher Amato CSAIL, MIT Cambridge, MA 02139 camato@csail.mit.edu Frans A. Oliehoek...state of a special POMDP, called a BA- POMDP. The BA-POMDP can be extended to the multiagent setting ( Amato and Oliehoek 2013), yielding the Bayes...2012; Amato et al. 2013) in the form of factored Dec-POMDPs (Oliehoek, Whiteson, and Spaan 2013; Pajarinen and Pel- tonen 2011) and networked

Secular Trends in Pupils' Assessments of Physical Education Lessons in Regard to Their Self-Perception of Physical Fitness across the Educational Systems of Czech Republic and Poland

ERIC Educational Resources Information Center

Frömel, Karel; Vašícková, Jana; Svozil, Zbynek; Chmelík, František; Skalik, Krzysztof; Groffik, Dorota

2014-01-01

Observation of trends in physical education plays an integral role in motor-development diagnostics and in encouraging physical activity and a healthy lifestyle. This study aims to elucidate the current state of and trends in pupils' assessments of physical education lessons (PELs) in different education systems in the context of self-perception…

Automatically Detecting Authors’ Native Language

DTIC Science & Technology

2011-03-01

exploring stylistic idiosyncrasies in the author’s writing [15]. Kop- pel used the data from International Corpus of Learner English version 1, which is... stylistic feature sets such as function words, letter n-grams, and er- rors and idiosyncrasies [15]. 1. Function words: 400 specific function words were...language on the choice of written second language words. Proceedings of the Workshop on Cognitive Aspects of Computation Language Acquisition, pp. 9–16

Next-Generation Fire Extinguishing Agent. Phase 4. Foundation for New Training Agent Development

DTIC Science & Technology

1989-12-01

Administration PCE perchloroethylene PEL Permissible Exposure Limit QSAR Quantitative Structure Activity Relationship SBUV Solar Backscatter Ultraviolet xi...can pass through the troposphere without destruction to enter the stratosphere. In the stratosphere, they photolyze in the intense solar radiation to...radiation, UV-B, striking the earth. Preliminary data from a Solar Backscatter Ultraviolet (SBUV) instrument aboard NASA’s Nimbus 7 satellite show a

Cold Water Cleaning and Sanitizing of Kitchenware in the Field

DTIC Science & Technology

1989-12-01

product would not be expected Product may result in irritat tact dermatitis have been rep benzalkonium chloride compoun mists or vapors may result in...CONSERVATION COLD WATER 19. ABSTRACT {Continue on reverse if necessary and identify by block number) In emergency situations in the field, where reduction ...MATERIAL: <CAS#) ! % Bv Wt. I TLV I PEL n-Alkyl Dimethyl Benzyl Ammonium Chloride (68424-85-1) Octyl decy I dimethyl

Intein-mediated one-step purification of Escherichia coli secreted human antibody fragments.

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

Wu, Wan-Yi; Miller, Keith D.; Coolbaugh, Michael

In this work, we apply self-cleaving affinity tag technology to several target proteins secreted into the Escherichia coli periplasm, including two with disulfide bonds. The target proteins were genetically fused to a self-cleaving chitin-binding domain intein tag for purification via a chitin agarose affinity resin. By attaching the intein-tagged fusion genes to the PelB secretion leader sequence, the tagged target proteins were secreted to the periplasmic space and could be recovered in active form by simple osmotic shock. After chitin-affinity purification, the target proteins were released from the chitin-binding domain tag via intein self-cleaving. This was induced by a smallmore » change in pH from 8.5 to 6.5 at room temperature, allowing direct elution of the cleaved target protein from the chitin affinity resin. The target proteins include the E. coli maltose-binding protein and b-lactamase enzyme, as well as two human antibody fragments that contain disulfide bonds. In all cases, the target proteins were purified with good activity and yield, without the need for refolding. Overall, this work demonstrates the compatibility of the DI-CM intein with the PelB secretion system in E. coli, greatly expanding its potential to more complex proteins.« less

Eclipse parcial de Luna - 23-24 de Marzo de 1997

NASA Astrophysics Data System (ADS)

Arquiola, A. P.; Arquiola, F. E.

Luego de varios años en que las condiciones climáticas no nos permitían registrar el fenómeno, pudimos observar y realizar secuencias fotográficas del eclipse parcial Luna. Siendo de una magnitud de 0.92 (muy cercano a la totalidad) se obtuvo una serie de fotografías muy claras y preferentemente con gran contraste a fin de destacar las tonalidades de las sombras, en especial la penumbra, que desde ya el clima nos favoreció. Los métodos fotográficos fueron, en primer lugar, con telezoom de 210mm a f/4.5 con película color de 1600 ASA; y el ya clásico método a foco primario en el Telescopio Schmidt - Cassegrain de 200mm a f/10. Paralelamente a la observación del eclipse, estábamos al instante comunicados por correo electrónico con otros observadores desde diferentes lugares del mundo intercambiando reportes, y también usuarios en general de la red, de esta forma se hizo muy especial el fenómeno. Instrumentos utilizados : Telescopio Schmidt-Cassegrain 200mm f/10, Cámara fotográfica Minolta con Telezoom 210mm f/4.5, Película 1600 ASA color, Telescopio Refractor 80mm a f/15

Role of bronchodilation and pattern of breathing in increasing tidal expiratory flow with progressive induced hypercapnia in chronic obstructive pulmonary disease.

PubMed

Finucane, Kevin E; Singh, Bhajan

2018-01-01

Hypercapnia (HC) in vitro relaxes airway smooth muscle; in vivo, it increases respiratory effort, tidal expiratory flows (V̇ exp ), and, by decreasing inspiratory duration (Ti), increases elastic recoil pressure (Pel) via lung viscoelasticity; however, its effect on airway resistance is uncertain. We examined the contributions of bronchodilation, Ti, and expiratory effort to increasing V̇ exp with progressive HC in 10 subjects with chronic obstructive pulmonary disease (COPD): mean forced expiratory volume in 1 s (FEV 1 ) 53% predicted. Lung volumes (Vl), V̇ exp , esophageal pressure (Pes), Ti, and end-tidal Pco 2 ([Formula: see text]) were measured during six tidal breaths followed by an inspiratory capacity (IC), breathing air, and at three levels of HC. V̇ exp and V̇ with submaximal forced vital capacities breathing air (V̇ sFVC ) were compared. Pulmonary resistance ( Rl) was measured from the Pes-V̇ relationship. V̇ exp and Pes at end-expiratory lung volume (EELV) + 0.3 tidal volume [V̇ (0.3Vt) and Pes (0.3Vt) , respectively], Ti, and Rl correlated with [Formula: see text] ( P < 0.001 for all) and were independent of tiotropium. [Formula: see text], Ti, and Pes (0.3Vt) predicted the increasing V̇ (0.3Vt) /V̇ sFVC(0.3Vt) [multiple regression analysis (MRA): P = 0.001, 0.004, and 0.025, respectively]. At [Formula: see text] ≥ 50 Torr, V̇ (0.3Vt) /V̇ sFVC(0.3Vt) exceeded unity in 30 of 36 measurements and was predicted by [Formula: see text] and Pes (0.3Vt) (MRA: P = 0.02 and 0.025, respectively). Rl decreased at [Formula: see text] 45 Torr ( P < 0.05) and did not change with further HC. IC and Vl (0.3Vt) did not change with HC. We conclude that in COPD HC increases V̇ exp due to bronchodilation, increased Pel secondary to decreasing Ti, and increased expiratory effort, all promoting lung emptying and a stable EELV. NEW & NOTEWORTHY The response of airways to intrapulmonary hypercapnia (HC) is uncertain. In chronic obstructive pulmonary disease (COPD), progressive HC increases tidal expiratory flows by inducing bronchodilation and via an increased rate of inspiration and lung viscoelasticity, a probable increase in lung elastic recoil pressure, both changes increasing expiratory flows, promoting lung emptying and a stable end-expiratory volume. Bronchodilation with HC occurred despite optimal standard bronchodilator therapy, suggesting that in COPD further bronchodilation is possible.

The National Shipbuilding Research Program, Welding Fume Study

DTIC Science & Technology

1999-01-01

gathering air sample data, and addressing the impact of the anticipated reduction. It is anticipated that the PEL for hexavalent chromium will be...associated with Cr, Cr6, Ni, and Mn are discussed below: Chromium (Cr) Cr is a cancer causing agent and a mutagen in humans. It has been shown to cause...reported to cause lung allergy. Once allergy develops, even small future exposures may cause cough, wheezing, or shortness of breath. Hexavalent Chromium

Novel Approach for Welding Stainless Steel Using Cr-Free Welding Consumables

DTIC Science & Technology

2004-12-31

Breakdown potential ERP Repassivation potential SS Stainless steel SMAW Shielded metal arc welding GTAW Gas tungsten arc welding PEL Permissible...0.1 M NaCl. 14 4. List of Tables Table 1. Details of GTAW procedure. 7 1 5. Acknowledgements The work in this report was...resistance, filler metals matching or exceeding the chromium (Cr) content of the base metal must be used. The Cr content of Types 304 and 308 stainless

Spatial Distribution, Chemical Fraction and Fuzzy Comprehensive Risk Assessment of Heavy Metals in Surface Sediments from the Honghu Lake, China

PubMed Central

Xiao, Minsi; Zhang, Jingdong; Liu, Chaoyang; Qiu, Zhenzhen; Cai, Ying

2018-01-01

Spatial concentrations and chemical fractions of heavy metals (Cr, Cu, Pb, Zn and Cd) in 16 sampling sites from the Honghu Lake were investigated using an atomic absorption spectrophotometer and optimized BCR (the European Community Bureau of Reference) three-stage extraction procedure. Compared with the corresponding probable effect levels (PELs), adverse biological effects of the studied five sediment metals decreased in the sequence of Cr > Cu > Zn > Pb > Cd. Geo-accumulation index (Igeo) values for Cr, Cu, Pb and Zn in each sampling site were at un-contamination level, while the values for Cd varied from un-contamination level to moderate contamination level. Spatially, the enrichment degree of Cd in lower part of the South Lake, the west part of the North Lake and the outlet were higher than the other parts of Honghu Lake. For metal chemical fractions, the proportions of the acid-extractable fraction of five metal contents were in the descending order: Cd, Cu, Zn, Pb and Cr. Cd had the highest bioaccessibility. Being the above indexes focused always on heavy metals’ total content or chemical fraction in deterministic assessment system, which may confuse decision makers, the fuzzy comprehensive risk assessment method was established based on PEI (Potential ecological risk index), RAC (Risk assessment code) and fuzzy theory. Average comprehensive risks of heavy metals in sediments revealed the following orders: Cd (considerable risk) > Cu (moderate risk) > Zn (low risk) > Pb > Cr. Thus, Cd and Cu were determined as the pollutants of most concern. The central part of South Honghu Lake (S4, S5, S6, S9, S12 and S14), east part of the North Honghu Lake (S1) and outlet of outlet of the Honghu Lake (S10) were recommended as the priority control areas. Specifically, it is necessary to pay more attention to S1, S4, S5, S6, S9 and S16 when decision making for their calculated membership values (probabilities) of adjacent risk levels quite close. PMID:29373483

Toward an integrative spatiotemporal architecture of the magma plumbing system leading to systematic Plinian eruption at Montagne Pelée Martinique (Lesser Antilles)

NASA Astrophysics Data System (ADS)

Boudon, G.; Balcone-Boissard, H.; Lyonnet, E.; Morgan, D. J.

2017-12-01

The dynamic of crustal magma reservoir may be at the origin of pressure/temperature variations that may trigger magma ascent and eruption. These changes can be registered during crystal growth and can probably produce at the surface geophysical or/and geochemical signals that could be registered by monitoring network, constituting precursory signals. For volcanoes where the plumbing system is well established in terms of volume and depth for a given cycle, repetitive eruptions of the same order of magnitude and involving similar magma composition may occur. It was the case for Montagne Pelée (Martinique, Lesser Antilles), sadly known for the 1902 lava dome-forming eruption that killed 30 000 inhabitants, and that produce repetitive Plinian eruptions in the last 15 ky. Are the perturbations in the dynamic of the magma storage identical for all these eruptions and is the timescale between these perturbations and the eruptions in the same order of magnitude? In the last decade, intracristalline diffusion modelling has been increasingly used to constrain timescale of magmatic processes. Recently this kind of investigations has been coupled to a petrological model of the magma storage region to better wholly describe its behaviour through a Crystal System Analysis (CSA) approach. Here we aim at constraining the pre-eruptive dynamic of the reservoir giving birth to the Plinian eruptions at Montagne Pelée. Precisely we attempt to identify the processes at the origin of the eruptions and the timescale between this process and the eruption. By studying the last five Plinian eruptions of this volcano the question of the systematic occurrence of one process at the same time prior eruption will be discussed. To achieve this goal we performed a detailed petrological description of the eruptive products of the first Plinian phase of these eruptions to build a CSA tree through EPMA and SEM analyses, coupled to Fe-Mg diffusion modelling in orthopyroxenes to retrieve timescale between the perturbation identified in the reservoir and the eruption. We thus highlight that: i) the perturbation event is not systematically the same through all eruptions; ii) the timescale that separate this event from the eruptions is in the order of 4-6 months, significantly shorter that what was up to now estimated for large silicic eruptions.

Revisiting 26Al-26Mg systematics of plagioclase in H4 chondrites

NASA Astrophysics Data System (ADS)

Telus, M.; Huss, G. R.; Nagashima, K.; Ogliore, R. C.

2014-06-01

Zinner and Göpel found clear evidence for the former presence of 26Al in the H4 chondrites Ste. Marguerite and Forest Vale. They assumed that the 26Al-26Mg systematics of these chondrites date "metamorphic cooling of the H4 parent body." Plagioclase in these chondrites can have very high Al/Mg ratios and low Mg concentrations, making these ion probe analyses susceptible to ratio bias, which is inversely proportional to the number of counts of the denominator isotope (Ogliore et al.). Zinner and Göpel used the mean of the ratios to calculate the isotope ratios, which exacerbates this problem. We analyzed the Al/Mg ratios and Mg isotopic compositions of plagioclase grains in thin sections of Ste. Marguerite, Forest Vale, Beaver Creek, and Sena to evaluate the possible influence of ratio bias on the published initial 26Al/27Al ratios for these meteorites. We calculated the isotope ratios using total counts, a less biased method of calculating isotope ratios. The results from our analyses are consistent with those from Zinner and Göpel, indicating that ratio bias does not significantly affect 26Al-26Mg results for plagioclase in these chondrites. Ste. Marguerite has a clear isochron with an initial 26Al/27Al ratio indicating that it cooled to below 450 °C 5.2 ± 0.2 Myr after CAIs. The isochrons for Forest Vale and Beaver Creek also show clear evidence that 26Al was alive when they cooled, but the initial 26Al/27Al ratios are not well constrained. Sena does not show evidence that 26Al was alive when it cooled to below the Al-Mg closure temperature. Given that metallographic cooling rates for Ste. Marguerite, Forest Vale, and Beaver Creek are atypical (>5000 °C/Myr at 500 °C) compared with most H4s, including Sena, which have cooling rates of 10-50 °C/Myr at 500 °C (Scott et al.), we conclude that the Al-Mg systematics for Ste. Marguerite, Forest Vale, and Beaver Creek are the result of impact excavation of these chondrites and cooling at the surface of the parent body, instead of undisturbed cooling at depth in the H chondrite parent body, like many have assumed.

Detection of hydrogen peroxide based on long-path absorption spectroscopy using a CW EC-QCL

NASA Astrophysics Data System (ADS)

Sanchez, N. P.; Yu, Y.; Dong, L.; Griffin, R.; Tittel, F. K.

2016-02-01

A sensor system based on a CW EC-QCL (mode-hop-free range 1225-1285 cm-1) coupled with long-path absorption spectroscopy was developed for the monitoring of gas-phase hydrogen peroxide (H2O2) using an interference-free absorption line located at 1234.055 cm-1. Wavelength modulation spectroscopy (WMS) with second harmonic detection was implemented for data processing. Optimum levels of pressure and modulation amplitude of the sensor system led to a minimum detection limit (MDL) of 25 ppb using an integration time of 280 sec. The selected absorption line for H2O2, which exhibits no interference from H2O, makes this sensor system suitable for sensitive and selective monitoring of H2O2 levels in decontamination and sterilization processes based on Vapor Phase Hydrogen Peroxide (VPHP) units, in which a mixture of H2O and H2O2 is generated. Furthermore, continuous realtime monitoring of H2O2 concentrations in industrial facilities employing this species can be achieved with this sensing system in order to evaluate average permissible exposure levels (PELs) and potential exceedances of guidelines established by the US Occupational Safety and Health Administration for H2O2.

What Employees Need (and Want) to Hear When Justifying the Suspension of a Regulated Metals Plan for the Processing of Drums Containing Metal Turnings

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

Todd Potts, T.; Hylko, J.M.

2008-07-01

A Regulated Metals Plan (RMP) was implemented for outdoor work activities involving the removal and disposition of approximately 4,000 deteriorated waste drums containing 236 metric tonnes (260 tons) of lead turnings from various, unspecified machine shop facilities at the Paducah Gaseous Diffusion Plant. Until exposure monitoring could prove otherwise, the work area established for processing the drums was conservatively defined as a Lead Regulated Area (LRA) subject to the Occupational Safety and Health Administration's Lead Standard found in Title 29 of the Code of Federal Regulations, Part 1910.1025. The vast majority of the analytical results for the industrial hygiene breathingmore » zone samples collected and tested for arsenic, beryllium, cadmium, chromium, lead, nickel, selenium, silver, and thallium using the National Institute for Occupational Safety and Health's analytical method 7300 were equivalent to the laboratory detection limits for each analyte. All results were less than 6% of their respective Permissible Exposure Limits (PEL), except for one nickel result that was approximately 17% of its PEL. The results provided justification to eventually down-post the LRA to existing employee protection requirements. In addition to removing the deteriorated drums and accompanying debris, the success of this project was quantified in terms of zero recordable injuries. The primary contributor in achieving this success was the sharing and communication of information between management, safety, and the field teams. Specifically, this was what the employees needed (and wanted) to hear when justifying the suspension of the RMP for the processing of drums containing metal turnings. Daily briefings on the status of the project and field monitoring results were just as important as maintaining budget and schedule milestones. Also, the Environmental, Safety and Health organization maintained its presence by continuing to monitor evolving field conditions to ensure the effectiveness of its plans and procedures. (authors)« less

Identification of Caspase Cleavage Sites in KSHV Latency-Associated Nuclear Antigen and Their Effects on Caspase-Related Host Defense Responses.

PubMed

Davis, David A; Naiman, Nicole E; Wang, Victoria; Shrestha, Prabha; Haque, Muzammel; Hu, Duosha; Anagho, Holda A; Carey, Robert F; Davidoff, Katharine S; Yarchoan, Robert

2015-07-01

Kaposi's sarcoma-associated herpesvirus (KSHV), also known as human herpesvirus-8, is the causative agent of three hyperproliferative disorders: Kaposi's sarcoma, primary effusion lymphoma (PEL) and multicentric Castleman's disease. During viral latency a small subset of viral genes are produced, including KSHV latency-associated nuclear antigen (LANA), which help the virus thwart cellular defense responses. We found that exposure of KSHV-infected cells to oxidative stress, or other inducers of apoptosis and caspase activation, led to processing of LANA and that this processing could be inhibited with the pan-caspase inhibitor Z-VAD-FMK. Using sequence, peptide, and mutational analysis, two caspase cleavage sites within LANA were identified: a site for caspase-3 type caspases at the N-terminus and a site for caspase-1 and-3 type caspases at the C-terminus. Using LANA expression plasmids, we demonstrated that mutation of these cleavage sites prevents caspase-1 and caspase-3 processing of LANA. This indicates that these are the principal sites that are susceptible to caspase cleavage. Using peptides spanning the identified LANA cleavage sites, we show that caspase activity can be inhibited in vitro and that a cell-permeable peptide spanning the C-terminal cleavage site could inhibit cleavage of poly (ADP-ribose) polymerase and increase viability in cells undergoing etoposide-induced apoptosis. The C-terminal peptide of LANA also inhibited interleukin-1 beta (IL-1β) production from lipopolysaccharide-treated THP-1 cells by more than 50%. Furthermore, mutation of the two cleavage sites in LANA led to a significant increase in IL-1β production in transfected THP-1 cells; this provides evidence that these sites function to blunt the inflammasome, which is known to be activated in latently infected PEL cells. These results suggest that specific caspase cleavage sites in KSHV LANA function to blunt apoptosis as well as interfere with the caspase-1-mediated inflammasome, thus thwarting key cellular defense mechanisms.

Asbestos release from whole-building demolition of buildings with asbestos-containing material.

PubMed

Perkins, Robert A; Hargesheimer, John; Fourie, Walter

2007-12-01

The whole-building demolition method, which entails one-or two-story buildings pushed down by heavy equipment, loaded into trucks, and hauled away, is generally the most cost-effective means to remove small buildings. For taller buildings, a crane and wrecking ball may be used initially to reduce the height of the building. Demolitions might release asbestos fibers from friable asbestos-containing material (ACM). Fibers also might be released from nominally nonfriable ACM (Categories I and II nonfriable ACM) if it becomes friable after rough handling throughout the whole-building demolition process. This paper reports on asbestos air monitoring from two demolition projects involving ACM. In one building, Category II nonfriable ACM was present because it could not be removed safely prior to demolition. Both projects had large quantities of gypsum wallboard with ACM joint compound and ACM flooring. One building had large quantities of ACM spray-on ceiling material. During the demolitions personal air monitoring of the workers and area air monitoring downwind and around the sites were conducted. The monitoring found the concentrations of fibers detected by phase contrast microscopy were generally well below the permissible exposure limits (PEL) of workers. Electron microcopy analysis of samples at or near the PEL indicated most of the fibers were not asbestos, and the actual asbestos exposure was often below the detection limit of the procedure. The buildings were kept wet with fire hoses during the demolition and that required large quantities of water, 20,000-60,000 gal/day (75-225 m(3)/day). Earlier studies found little asbestos release from buildings containing only nonfriable ACM demolished by this method. This project found a negligible release of asbestos fibers, despite the presence of nonfriable materials that might become friable, such as ACM joint compound and spray-on ACM ceiling coating.

Role of polysaccharides in Pseudomonas aeruginosa biofilm development

PubMed Central

Ryder, Cynthia; Byrd, Matthew; Wozniak, Daniel J.

2008-01-01

During the past decade, there has been a renewed interest in using P. aeruginosa as a model system for biofilm development and pathogenesis. Since the biofilm matrix represents a critical interface between the bacterium and the host or its environment, considerable effort has been expended to acquire a more complete understanding of the matrix composition. Here, we focus on recent developments regarding the roles of alginate, Psl, and Pel polysaccharides in the biofilm matrix. PMID:17981495

Metal dust exposure and lung function deterioration among steel workers: an exposure-response relationship.

PubMed

Hamzah, Nurul Ainun; Mohd Tamrin, Shamsul Bahri; Ismail, Noor Hassim

2016-07-01

Metallic dust is a heterogeneous substance with respiratory sensitizing properties. Its long term exposure adversely affected lung function, thus may cause acute or chronic respiratory diseases. A cross-sectional study was conducted in a steel factory in Terengganu, Malaysia to assess the metal dust exposure and its relationship to lung function values among 184 workers. Metal dust concentrations values (Co, Cr, and Ni) for each worker were collected using air personal sampling. Lung function values (FEV 1 , FVC, and %FEV 1 /FVC) were determined using spirometer. Exposure to cobalt and chromium were 1-3 times higher than permissible exposure limit (PEL) while nickel was not exceeding the PEL. Cumulative of chromium was the predictor to all lung function values (FEV 1 , FVC, and %FEV 1 /FVC). Frequency of using mask was positively associated with FVC (Adj b = 0.263, P = 0.011) while past respiratory illnesses were negatively associated with %FEV 1 /FVC (Adj b = -1.452, P = 0.026). Only few workers (36.4%) were found to wear their masks all times during the working hours. There was an exposure-response relationship of cumulative metal dust exposure with the deterioration of lung function values. Improvement of control measures as well as proper and efficient use or personal protection equipment while at work could help to protect the respiratory health of workers.

Notes about Alta Vista in Chalchihuites, Zacatecas

NASA Astrophysics Data System (ADS)

Montero García, Ismael Arturo

2016-11-01

The Tropic of Cancer is a parallel located at the latitude of 23°26'16''. This imaginary line extends across northern Mexico from the southernmost point of the Baja California Peninsula, to the Gulf of Mexico, passing through the states of Baja California Sur, Sinaloa, Durango, Zacatecas, San Luis Potosí, Nuevo León and Tamaulipas. The Tropic of Cancer marks the northernmost position of the sun at its midday zenith, which takes place in the Summer solstice. On this day, the sun's rays hit the earth's surface vertically along the entire length of this latitude, which was supposed to be significant for the priest/astronomers of ancient times, who dedicated themselves to observing the apparent movements of the sun. It so happens that Alta Vista in Zacatecas, corresponds to the westernmost peak where this phenomenon can occur, although the date of the zenith's course differs depending on the latitude of each position and so various archaeoastronomical specialists stress how the ancient indigenous cultures, at least those dating from Mexico's Classical period, valued this finding in developing their calendars. On the other hand, the research contributes new elements for discussion because it presents a calendar of the horizon, based on of the highest peaks of the Sierra Prieta mountain range ranging from the archaeological sites of El Chapín, Cerro Pedregoso, to the excavations at El Picacho Pelón (peak El Pelón).

Nucleation of Bubbles by Electrons in Liquid Helium-4

NASA Astrophysics Data System (ADS)

Yang, Y.; Sirisky, S.; Wei, W.; Seidel, G. M.; Maris, H. J.

2018-02-01

We report on experiments in which we study cavitation resulting from electrons in liquid helium. Electrons are introduced into the liquid by a radioactive source. After an electron comes to rest in the liquid, it forces open a small cavity referred to as an electron bubble. To study cavitation, a sound pulse is generated by means of a hemispherical piezoelectric transducer producing a large-amplitude pressure oscillation at the acoustic focus. If an electron is in the vicinity of the focus and the negative-going pressure swing exceeds a critical value, a cavitation bubble is produced which can be detected by light scattering. Two distinct critical pressures P_{el} and P_{rare} have been measured. The first corresponds to cavitation resulting from the application of a reduced pressure to liquid containing an electron which has already formed an electron bubble. The second is the critical pressure needed to lead to cavitation when an electron enters the liquid at a time and place where there is already a reduced pressure. We have measured these two pressures as a function of temperature and consider possible explanations for the difference between them. In addition to these clearly seen cavitation thresholds, there are some cavitation events that have been detected with a threshold that is at an even smaller negative pressure than P_{el} and P_{rare}.

Screening Brazilian Macrophomina phaseolina isolates for alkaline lipases and other extracellular hydrolases.

PubMed

Schinke, Claudia; Germani, José C

2012-03-01

Macrophomina phaseolina, phylum Ascomycota, is a phytopathogenic fungus distributed worldwide in hot dry areas. There are few studies on its secreted lipases and none on its colony radial growth rate, an indicator of fungal ability to use nutrients for growth, on media other than potato-dextrose agar. In this study, 13 M. phaseolina isolates collected in different Brazilian regions were screened for fast-growth and the production of hydrolases of industrial interest, especially alkaline lipases. Hydrolase detection and growth rate determination were done on citric pectin, gelatin, casein, soluble starch, and olive oil as substrates. Ten isolates were found to be active on all substrates tested. The most commonly detected enzymes were pectinases, amylases, and lipases. The growth rate on pectin was significantly higher (P < 0.05), while the growth rates on the different media identified CMM 2105, CMM 1091, and PEL as the fastest-growing isolates. The lipase activity of four isolates grown on olive oil was followed for 4 days by measuring the activity in the cultivation broth. The specific lipolytic activity of isolate PEL was significantly higher at 96 h (130 mU mg protein(-1)). The broth was active at 37 °C, pH 8, indicating the potential utility of the lipases of this isolate in mild alkaline detergents. There was a strong and positive correlation (0.86) between radial growth rate and specific lipolytic activity.

Candida albicans ethanol stimulates Pseudomonas aeruginosa WspR-controlled biofilm formation as part of a cyclic relationship involving phenazines.

PubMed

Chen, Annie I; Dolben, Emily F; Okegbe, Chinweike; Harty, Colleen E; Golub, Yuriy; Thao, Sandy; Ha, Dae Gon; Willger, Sven D; O'Toole, George A; Harwood, Caroline S; Dietrich, Lars E P; Hogan, Deborah A

2014-10-01

In chronic infections, pathogens are often in the presence of other microbial species. For example, Pseudomonas aeruginosa is a common and detrimental lung pathogen in individuals with cystic fibrosis (CF) and co-infections with Candida albicans are common. Here, we show that P. aeruginosa biofilm formation and phenazine production were strongly influenced by ethanol produced by the fungus C. albicans. Ethanol stimulated phenotypes that are indicative of increased levels of cyclic-di-GMP (c-di-GMP), and levels of c-di-GMP were 2-fold higher in the presence of ethanol. Through a genetic screen, we found that the diguanylate cyclase WspR was required for ethanol stimulation of c-di-GMP. Multiple lines of evidence indicate that ethanol stimulates WspR signaling through its cognate sensor WspA, and promotes WspR-dependent activation of Pel exopolysaccharide production, which contributes to biofilm maturation. We also found that ethanol stimulation of WspR promoted P. aeruginosa colonization of CF airway epithelial cells. P. aeruginosa production of phenazines occurs both in the CF lung and in culture, and phenazines enhance ethanol production by C. albicans. Using a C. albicans adh1/adh1 mutant with decreased ethanol production, we found that fungal ethanol strongly altered the spectrum of P. aeruginosa phenazines in favor of those that are most effective against fungi. Thus, a feedback cycle comprised of ethanol and phenazines drives this polymicrobial interaction, and these relationships may provide insight into why co-infection with both P. aeruginosa and C. albicans has been associated with worse outcomes in cystic fibrosis.

Buffing, burnishing, and stripping of vinyl asbestos floor tile

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

Hollett, B.A.; Edwards, A.; Clark, P.J.

Studies were conducted to evaluate airborne asbestos concentrations during the three principal types of preventative maintenance (low-speed spray-buffing, ultra high-speed burnishing, and wet-stripping) used on asbestos-containing floor tiles. These were done under pre-existing and prepared levels of floor care maintenance. Airborne asbestos concentrations were measured before and during each floor care procedure to determine the magnitude of the increase in airborne asbestos levels during each procedure. Airborne total fiber concentrations were also measured for comparison with the Occupational Safety and Health Administration`s (OSHA) Permissible Exposure Limit (PEL) of 0.1 f/cm{sup 3}. Low-speed spray-buffing and wet-stripping were evaluated on pre-existing floormore » conditions and three levels of prepared floor care conditions (poor, medium, and good). Ultra high-speed burnishing and wet-stripping were evaluated on two levels of prepared floor care conditions (poor and good). Floor care conditions were defined in consultation with the Chemical Specialty Manufacturers Association and other representatives of floor-care chemical manufacturers. Controlled studies were conducted in an unoccupied building at the decommissioned Chanute Air Force Base in Rantoul, Illinois, with the cooperation of the U.S. Air Force. The building offered approximately 8600 ft{sup 2} of open floor space tiled with 9-inch by 9-inch resilient floor tile containing approximately 5% chrysotile asbestos.« less

Assessment of Ni, Cu, Zn and Pb levels in beach and dune sands from Havana resorts, Cuba.

PubMed

Díaz Rizo, Oscar; Buzón González, Fran; Arado López, Juana O

2015-11-15

Concentrations of nickel (Ni), copper (Cu), zinc (Zn) and lead (Pb) in beach and dune sands from thirteen Havana (Cuba) resorts were estimated by X-ray fluorescence analysis. Determined mean metal contents (in mg·kg(-1)) in beach sand samples were 28±12 for Ni, 35±12 for Cu, 31±11 for Zn and 6.0±1.8 for Pb, while for dune sands were 30±15, 38±22, 37±15 and 6.8±2.9, respectively. Metal-to-iron normalization shows moderately severe and severe enrichment by Cu. The comparison with sediment quality guidelines shows that dune sands from various resorts must be considered as heavily polluted by Cu and Ni. Almost in every resort, the Ni and Cu contents exceed their corresponding TEL values and, in some resorts, the Ni PEL value. The comparison with a Havana topsoil study indicates the possible Ni and Cu natural origin. Copyright © 2015 Elsevier Ltd. All rights reserved.

Genomic analysis reveals the biotechnological and industrial potential of levan producing halophilic extremophile, Halomonas smyrnensis AAD6T.

PubMed

Diken, Elif; Ozer, Tugba; Arikan, Muzaffer; Emrence, Zeliha; Oner, Ebru Toksoy; Ustek, Duran; Arga, Kazim Yalcin

2015-01-01

Halomonas smyrnensis AAD6T is a gram negative, aerobic, and moderately halophilic bacterium, and is known to produce high levels of levan with many potential uses in foods, feeds, cosmetics, pharmaceutical and chemical industries due to its outstanding properties. Here, the whole-genome analysis was performed to gain more insight about the biological mechanisms, and the whole-genome organization of the bacterium. Industrially crucial genes, including the levansucrase, were detected and the genome-scale metabolic model of H. smyrnensis AAD6T was reconstructed. The bacterium was found to have many potential applications in biotechnology not only being a levan producer, but also because of its capacity to produce Pel exopolysaccharide, polyhydroxyalkanoates, and osmoprotectants. The genomic information presented here will not only provide additional information to enhance our understanding of the genetic and metabolic network of halophilic bacteria, but also accelerate the research on systematical design of engineering strategies for biotechnology applications.

Modeling of projection electron lithography

NASA Astrophysics Data System (ADS)

Mack, Chris A.

2000-07-01

Projection Electron Lithography (PEL) has recently become a leading candidate for the next generation of lithography systems after the successful demonstration of SCAPEL by Lucent Technologies and PREVAIL by IBM. These systems use a scattering membrane mask followed by a lens with limited angular acceptance range to form an image of the mask when illuminated by high energy electrons. This paper presents an initial modeling system for such types of projection electron lithography systems. Monte Carlo modeling of electron scattering within the mask structure creates an effective mask 'diffraction' pattern, to borrow the standard optical terminology. A cutoff of this scattered pattern by the imaging 'lens' provides an electron energy distribution striking the wafer. This distribution is then convolved with a 'point spread function,' the results of a Monte Carlo scattering calculation of a point beam of electrons striking the resist coated substrate and including the effects of beam blur. Resist exposure and development models from standard electron beam lithography simulation are used to simulate the final three-dimensional resist profile.

Flavoring exposure in food manufacturing.

PubMed

Curwin, Brian D; Deddens, Jim A; McKernan, Lauralynn T

2015-05-01

Flavorings are substances that alter or enhance the taste of food. Workers in the food-manufacturing industry, where flavorings are added to many products, may be exposed to any number of flavoring compounds. Although thousands of flavoring substances are in use, little is known about most of these in terms of worker health effects, and few have occupational exposure guidelines. Exposure assessment surveys were conducted at nine food production facilities and one flavor manufacturer where a total of 105 area and 74 personal samples were collected for 13 flavoring compounds including five ketones, five aldehydes, and three acids. The majority of the samples were below the limit of detection (LOD) for most compounds. Diacetyl had eight area and four personal samples above the LOD, whereas 2,3-pentanedione had three area samples above the LOD. The detectable values ranged from 25-3124 ppb and 15-172 ppb for diacetyl and 2,3-pentanedione respectively. These values exceed the proposed National Institute for Occupational Safety and Health (NIOSH) recommended exposure limit for these compounds. The aldehydes had the most detectable samples, with each of them having >50% of the samples above the LOD. Acetaldehyde had all but two samples above the LOD, however, these samples were below the OSHA PEL. It appears that in the food-manufacturing facilities surveyed here, exposure to the ketones occurs infrequently, however levels above the proposed NIOSH REL were found. Conversely, aldehyde exposure appears to be ubiquitous.

Electrodeposition of Nanocrystalline Co-P Coatings as a Hard Chrome Alternative (Briefing Charts)

DTIC Science & Technology

2011-02-10

chrome plating utilizes chromium in the hexavalent state (Cr6+) Cr6+ is a known carcinogen and poses a health risk to operators OSHA lowered the Cr6+ PEL...from 52 µg/m3 to 5 µg/m3 8 Apr 09, Memorandum, DoD Directive Hexavalent Chromium Management Policy NAVAIR Cr6+ Authorization Process Hard Chrome...Systems Allocation (ESA) data extrapolated across all FRCs over a 10 yr period Environmental Driver/Benefit (Hexavalent Chromium Plating at Navy

Substrate Independence of THz Vibrational Modes of Polycrystalline Thin Films of Molecular Solids in Waveguide THz-TDS

DTIC Science & Technology

2012-01-01

THz-TDS technique is investigated. The sample film of salicylic acid is studied using waveguide THz-TDS on three different metal substrates and two...vibrational modes with wave- guide THz-TDS. The investigation of substrate dependence is performed using salicylic acid as the test molecule. This...Al and a self assembled monolayer (SAM) on Au. Salicylic acid is first characterized in the pel- let form and then compared to the absorption features

Nanocrystalline Cobalt-Phosphorous Electroplating as an Alternative to Hard Chromium Electroplating

DTIC Science & Technology

2012-08-01

Validate pulsed electrodeposition of Nanocrystalline Cobalt-Phosphorous (nCoP) alloy coatings as a Hard Chrome electroplating alternative for DoD...limits Cr+6  Cathode Efficiency Cr Plating *Co PEL is 20 µg/m3  ≈5X faster than Chrome plating  Increased throughput  One nCo-P tank can...replace several hard chrome tanks  Bath is Stable nCoP Plating Approaches 100% Efficiency  Process Comparison CoP Technical Approach

Geochemical and geo-statistical assessment of selected heavy metals in the surface sediments of the Gorgan Bay, Iran.

PubMed

Bastami, Kazem Darvish; Bagheri, Hossein; Haghparast, Sarah; Soltani, Farzaneh; Hamzehpoor, Ali; Bastami, Mousa Darvish

2012-12-01

We investigated heavy metal concentrations of zinc (Zn), copper (Cu), chromium (Cr), and lead (Pb), their spatial distribution and enrichment factor index in surface sediments of the Gorgan Bay. Sediment Quality Guidelines were also applied to assess adverse biological effects of these metals. Heavy metals were determined by inductively coupled plasma-mass spectroscopy (ICP-MS). The results indicated mean concentrations (ppm) of heavy metals were (mean±S.D.) Pb: 11.5±4.88, Cu: 18±8.83, Zn: 42±22.15 and Cr: 32±15.19. Based on Enrichment index, the Gorgan Bay is a low-enriched to non-enriched bay. Heavy metal contents were lower than the standard limits of PEL, ERL, and ERM that reveal no threatening influence of the metals in the Bay. Copyright © 2012 Elsevier Ltd. All rights reserved.

Oligovalent Fab display on M13 phage improved by directed evolution.

PubMed

Huovinen, Tuomas; Sanmark, Hanna; Ylä-Pelto, Jani; Vehniäinen, Markus; Lamminmäki, Urpo

2010-03-01

Efficient display of antibody on filamentous phage M13 coat is crucial for successful biopanning selections. We applied a directed evolution strategy to improve the oligovalent display of a poorly behaving Fab fragment fused to phage gene-3 for minor coat protein (g3p). The Fab displaying clones were enriched from a randomly mutated Fab gene library with polyclonal anti-mouse IgG antibodies. Contribution of each mutation to the improved phenotype of one selected mutant was studied. It was found out that two point mutations had significant contribution to the display efficiency of Fab clones superinfected with hyperphage. The most dramatic effect was connected to a start codon mutation, from AUG to GUG, of the PelB signal sequence preceding the heavy chain. The clone carrying this mutation, FabM(GUG), displayed Fab 19-fold better and yielded twofold higher phage titers than the original Fab.

The Escherichia coli O157:H7 cattle immuno-proteome includes outer membrane protein A (OmpA), a modulator of adherence to bovine recto-anal junction squamous epithelial (RSE) cells

PubMed Central

Kudva, Indira T.; Krastins, Bryan; Torres, Alfredo G.; Griffin, Robert W.; Sheng, Haiqing; Sarracino, David A.; Hovde, Carolyn J.; Calderwood, Stephen B.; John, Manohar

2015-01-01

SUMMARY Building on previous studies, we defined the repertoire of proteins comprising the immuno-proteome of E. coli O157:H7 (O157) cultured in DMEM supplemented with norepinephrine (NE; O157 immuno-proteome), a β-adrenergic hormone that regulates E. coli O157 gene expression in the gastrointestinal tract, using a variation of a novel proteomics-based platform proteome mining tool for antigen discovery, called Proteomics-based Expression Library Screening (PELS; Kudva et al., 2006). The E. coli O157 immuno-proteome (O157-IP) comprised 91 proteins, and included those identified previously using PELS, and also proteins comprising DMEM- and bovine rumen fluid- proteomes. Outer membrane protein A (OmpA), a common component of the above proteomes, and reportedly a contributor to E. coli O157 adherence to cultured Hep-2 epithelial cells, was interestingly found to be a modulator rather than a contributor to E. coli O157 adherence to bovine recto-anal junction squamous epithelial (RSE) cells. Our results point to a role for yet to be identified members of the O157-IP in E. coli O157 adherence to RSE-cells, and additionally implicate a possible role for the OmpA regulator, TdcA, in the expression of such adhesins. Our observations have implications for development of efficacious vaccines for preventing E. coli O157 colonization of the bovine gastrointestinal tract. PMID:25643951

Metal dust exposure and lung function deterioration among steel workers: an exposure-response relationship

PubMed Central

Hamzah, Nurul Ainun; Mohd Tamrin, Shamsul Bahri; Ismail, Noor Hassim

2016-01-01

Background Metallic dust is a heterogeneous substance with respiratory sensitizing properties. Its long term exposure adversely affected lung function, thus may cause acute or chronic respiratory diseases. Methods A cross-sectional study was conducted in a steel factory in Terengganu, Malaysia to assess the metal dust exposure and its relationship to lung function values among 184 workers. Metal dust concentrations values (Co, Cr, and Ni) for each worker were collected using air personal sampling. Lung function values (FEV1, FVC, and %FEV1/FVC) were determined using spirometer. Results Exposure to cobalt and chromium were 1–3 times higher than permissible exposure limit (PEL) while nickel was not exceeding the PEL. Cumulative of chromium was the predictor to all lung function values (FEV1, FVC, and %FEV1/FVC). Frequency of using mask was positively associated with FVC (Adj b = 0.263, P = 0.011) while past respiratory illnesses were negatively associated with %FEV1/FVC (Adj b = –1.452, P = 0.026). Only few workers (36.4%) were found to wear their masks all times during the working hours. Conclusions There was an exposure-response relationship of cumulative metal dust exposure with the deterioration of lung function values. Improvement of control measures as well as proper and efficient use or personal protection equipment while at work could help to protect the respiratory health of workers. PMID:27392157

Simulating airless and/or hot planetary surfaces in the Planetary Emissivity Laboratory (PEL)

NASA Astrophysics Data System (ADS)

Maturilli, A.; Helbert, J.; D'Amore, M.

2010-12-01

A complete and extensive mineralogical survey of extraterrestrial bodies is actually possible only by means of remote sensing spectrometers, measuring the planetary surfaces in a spectral range that goes from the visible to the far infrared. The list of instruments still active today, observing the most interesting planets and bodies in our solar system is far too long to list them in this abstract. The important message is that all of them are sending to Earth a huge amount of data that needs to be correctly analysed, to infer the mineralogical composition of the observed regions on different targets. This requires laboratory data of relevant analogue materials under relevant conditions measured on a wide spectral range. At the Planetary Emissivity Laboratory (PEL) of DLR in Berlin two separate instruments, a Bruker IFS 88 and a Bruker Vertex 80V are operated in parallel and independently to measure reflectance and emissivity of planetary analogue materials to cover the 0.4 to 100 µm spectral range. The older IFS 88 is used to measure under room pressure and for emissivity measurements from low to moderate temperatures (up to 180° C), while the new Vertex 80V can be evacuated (below 1 mbar) and used to measure emissivity of moderate to very hot surfaces, reaching temperatures typical of the daily Mercury (beyond 500° C). The laboratory set-up and the already obtained results will be described, together with details about the online-archival and the standardized structure of the existing dataset.

Detection of human herpesvirus 8 by quantitative polymerase chain reaction: development and standardisation of methods.

PubMed

Speicher, David J; Johnson, Newell W

2012-09-11

Human herpesvirus 8 (HHV-8), the aetiological agent of Kaposi's sarcoma (KS), multicentric Castleman's disease (MCD), and primary effusion lymphoma (PEL) is rare in Australia, but endemic in Sub-Saharan Africa, parts of South-east Asia and Oceania. While the treatment of external KS lesions can be monitored by clinical observation, the internal lesions of KS, MCD and PEL require extensive and expensive internal imaging, or autopsy. In patients with MCD and PEL, if HHV-8 viraemia is not reduced quickly, ~50% die within 24 months. HHV-8 qPCR is a valuable tool for monitoring HHV-8 viraemia, but is not available in many parts of the world, including those with high prevalence of KS and HHV-8. A new molecular facility with stringent three-phase workflow was established, adhering to NPAAC and CLSI guidelines. Three fully validated quantitative assays were developed: two for detection and quantification of HHV-8; one for GAPDH, necessary for normalisation of viral loads in tissue and peripheral blood. The HHV-8 ORF73 and ORF26 qPCR assays were 100% specific. All qPCR assays, displayed a broad dynamic range (102 to 1010 copies/μL TE Buffer) with a limit of detection of 4.85x103, 5.61x102, and 2.59x102 copies/μL TE Buffer and a limit of quantification of 4.85x103, 3.01x102, and 1.38x102 copies/μL TE Buffer for HHV-8 ORF73, HHV-8 ORF26, and GAPDH respectively.The assays were tested on a panel of 35 KS biopsies from Queensland. All were HHV-8 qPCR positive with average viral load of 2.96x105 HHV-8 copies/μL DNA extract (range: 4.37x103 to 1.47x106 copies/μL DNA extract): When normalised these equate to an average viral load of 2.44x104 HHV-8 copies/103 cells (range: 2.20x102 to 7.38x105 HHV-8 copies/103 cells). These are the first fully optimised, validated and MIQE compliant HHV-8 qPCR assays established in Australia. They worked well for qualitative detection of HHV-8 in archival tissue, and are well-suited for quantitative detection in whole blood. They are now available for research, for clinical diagnosis of HHV-8 infection, and for monitoring treatment efficacy.

Advection within side-by-side liquid micro-cylinders in a cross-flow

NASA Astrophysics Data System (ADS)

Dong, Qingming; Sau, Amalendu

2017-11-01

The gaseous SO2 entrainment from outer air stream and dispersion in binary and ternary liquid micro-cylinders appearing side-by-side are examined hereby. The separation/attachment regulated non-uniform interfacial momentum exchange creates main stream driven "primary" and shear reversed "secondary" vortices in the liquid cylinders. At separation points, the sense of rotation of the generated "primary-secondary" vortex pair remains inward directed. We define such a vortex pair as the "inflow" type. However, at stagnation or attachment points, the sense of rotation of a "primary-primary" or "secondary-secondary" vortex pair remains outward directed, and such a vortex pair is defined as the "outflow" type. For the coupled water cylinders facing an oncoming stream contaminated by gaseous SO2, its absorption and internal transport are effectively controlled by dominant "inflow" and "outflow" natured dynamics of the said vortex pairs, besides by diffusion. The evolving "inflow" natured "primary-secondary" vortex pairs at separation points actively entrain the outer SO2, whereas the "outflow" natured vortex-pairs oppose SO2 entry through the stagnation regions. Moreover, the blockage induced steady-symmetric, steady-deflected, and flip-flopping air-jets through gaps, for varied gap-ratio (1 ≤ G/R ≤ 4) and Reynolds number (30 ≤ Re ≤ 160), create distinctive impact both on quantitative SO2 absorption (mso2 ') and convective nature of the SO2 transport in upper, lower, and middle cylinders, by virtue of modified strength and size of the inflow and outflow paired vortices. The present study shows that the tiny "secondary vortices" play important roles in SO2 entrainment and in effectively controlling the local absorption rate Rs o2. The sudden acceleration and upward/downward deflection of gap-flows enhanced near-neck advective SO2 entrainment by suitably strengthening the "inflow" natured local vortex dynamics. Conversely, for the reduced size of secondary vortices, the saturation becomes delayed. In addition, for decreased vertical spacing of micro-cylinders (R = 40 μm) falling below the diameter-length "2R," the SO2 absorption (mso2 ') only gets slower. We provide extensive analysis of two-phase transport phenomena in terms of interactive shear-stress, pressure, and characteristic time-ratio "Tr" of advection-diffusion processes, for varied G/R, Re, and liquid phase Peclet number "Pel" (96 ≤ Pel ≤ 1333), to present a better insight into the governing physics.

Evidence of transboundary mercury and other pollutants in the Puyango-Tumbes River basin, Ecuador-Peru.

PubMed

Marshall, Bruce G; Veiga, Marcello M; Kaplan, Robert J; Adler Miserendino, Rebecca; Schudel, Gary; Bergquist, Bridget A; Guimarães, Jean R D; Sobral, Luis G S; Gonzalez-Mueller, Carolina

2018-04-25

In Portovelo in southern Ecuador, 87 gold processing centers along the Puyango-Tumbes River produce an estimated 6 tonnes of gold per annum using a combination of mercury amalgamation and/or cyanidation and processing poly-metallic ores. We analysed total Hg, Hg isotopes, total arsenic, cadmium, copper, lead and zinc in water and sediment along the Puyango in 2012-2014. The highest total mercury (THg) concentrations in sediments were found within a 40 km stretch downriver from the processing plants, with levels varying between 0.78-30.8 mg kg-1 during the dry season and 1.80-70.7 mg kg-1 during the wet season, with most concentrations above the CCME (Canadian Council of Ministers of the Environment) Probable Effect Level (PEL) of 0.5 mg kg-1. Data from mercury isotopic analyses support the conclusion that mercury use during gold processing in Portovelo is the source of Hg pollution found downstream in the Tumbes Delta in Peru, 160 km away. The majority of the water and sediment samples collected from the Puyango-Tumbes River had elevated concentrations of, arsenic, cadmium, copper, lead and zinc exceeding the CCME thresholds for the Protection of Aquatic Life. At monitoring points immediately below the processing plants, total dissolved concentrations of these metals exceeded the thresholds by 156-3567 times in surface waters and by 19-740 times in sediment. The results illustrate a significant transboundary pollution problem involving Hg and other toxic metals, amplified by the fact that the Puyango-Tumbes River is the only available water source in the semi-arid region of northern Peru.

Candida albicans Ethanol Stimulates Pseudomonas aeruginosa WspR-Controlled Biofilm Formation as Part of a Cyclic Relationship Involving Phenazines

PubMed Central

Okegbe, Chinweike; Harty, Colleen E.; Golub, Yuriy; Thao, Sandy; Ha, Dae Gon; Willger, Sven D.; O'Toole, George A.; Harwood, Caroline S.; Dietrich, Lars E. P.; Hogan, Deborah A.

2014-01-01

In chronic infections, pathogens are often in the presence of other microbial species. For example, Pseudomonas aeruginosa is a common and detrimental lung pathogen in individuals with cystic fibrosis (CF) and co-infections with Candida albicans are common. Here, we show that P. aeruginosa biofilm formation and phenazine production were strongly influenced by ethanol produced by the fungus C. albicans. Ethanol stimulated phenotypes that are indicative of increased levels of cyclic-di-GMP (c-di-GMP), and levels of c-di-GMP were 2-fold higher in the presence of ethanol. Through a genetic screen, we found that the diguanylate cyclase WspR was required for ethanol stimulation of c-di-GMP. Multiple lines of evidence indicate that ethanol stimulates WspR signaling through its cognate sensor WspA, and promotes WspR-dependent activation of Pel exopolysaccharide production, which contributes to biofilm maturation. We also found that ethanol stimulation of WspR promoted P. aeruginosa colonization of CF airway epithelial cells. P. aeruginosa production of phenazines occurs both in the CF lung and in culture, and phenazines enhance ethanol production by C. albicans. Using a C. albicans adh1/adh1 mutant with decreased ethanol production, we found that fungal ethanol strongly altered the spectrum of P. aeruginosa phenazines in favor of those that are most effective against fungi. Thus, a feedback cycle comprised of ethanol and phenazines drives this polymicrobial interaction, and these relationships may provide insight into why co-infection with both P. aeruginosa and C. albicans has been associated with worse outcomes in cystic fibrosis. PMID:25340349

Real-time measurement and control of waste anesthetic gases during veterinary surgeries

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

Burkhart, J.E.; Stobbe, T.J.

1990-12-01

Veterinary clinics are typically small businesses without access to sophisticated occupational safety and health programs that may exist for larger firms or hospitals. Exposures to waste anesthetic gases have been linked to a myriad of adverse health-related conditions. Excessive exposures to anesthetic agents are possible because many of the clinics use portable gas delivery carts that are not designed to capture waste gases. While scavenging systems are available to remove waste anesthetic gases, the cost may be prohibitive for smaller clinics and the effectiveness of these systems has not been fully established in veterinary clinics. The National Institute for Occupationalmore » Safety and Health (NIOSH) recommends limiting exposures to nitrous oxide (N2O) to a time-weighted average (TWA) concentration of 25 ppm and halogenated agents to 2 ppm. The NIOSH TWA is based on the weight of the agent collected from a 45-L air sample by charcoal adsorption over a sampling period not to exceed 1 hr. The NIOSH criteria state that, in most situations, control of N2O to the TWA as defined will result in levels of approximately 0.5 ppm of the halogenated agent. At present, no Occupational Safety and Health Administration (OSHA) permissible exposure level (PEL) exists for exposure to anesthetic agents; nor do specific recommendations exist for veterinary scavenging systems. Waste anesthetic gas exposures were determined using a modified MIRAN 1A at five veterinary clinics operating within the Morgantown, West Virginia, vicinity. For unscavenged systems of methoxyflurane and halothane, 1-hr time-weighted average exposures ranged from 0.5 to 45.5 ppm and 0.2 to 105.4 ppm, respectively.« less

Ruiz Volcano: Preliminary report

NASA Astrophysics Data System (ADS)

Ruiz Volcano, Colombia (4.88°N, 75.32°W). All times are local (= GMT -5 hours).An explosive eruption on November 13, 1985, melted ice and snow in the summit area, generating lahars that flowed tens of kilometers down flank river valleys, killing more than 20,000 people. This is history's fourth largest single-eruption death toll, behind only Tambora in 1815 (92,000), Krakatau in 1883 (36,000), and Mount Pelée in May 1902 (28,000). The following briefly summarizes the very preliminary and inevitably conflicting information that had been received by press time.

Report of Operation FITZWILLIAM. Volume 1, Design of Operation and Summary of Results (REDACTED)

DTIC Science & Technology

1948-01-01

storage tanks {400 lbs/sq in) to pel’mit the collection o£ sampleD or gas in the vicinity of the radio- active clouc1. P~dicective LUlC.lysis of -~he gas...Corps Furnish ground dust sampling units and wrap-around countera. 4. Navy Naval :Research Lab. (a) FW:-nish ground dust sampling units...direct as necessar,r the collection or air• craft filters and gaseou.s samples trca aircraft based at Km.falem. (6) Vector Destro,.er-M:lne...Swee

The Dirigible: A Catalyst for Resource Exploitation in Remote Areas?

DTIC Science & Technology

1985-04-01

ir’ship (26’.: 13). .. Hybrid . A he ,vi er than air vehiLile which Lomb nes.’-. s.tar~ it (gas) anrid cly ,mi L (pro~pel 1er s, jet e, g ines ) li ft...another test with a hybrid airship (8:.33). TABLE 1. - Airships Rejected p The three remaining airships will be discussed next. All arc? hybrid LTAs...heavy-lift markets. (Drawing at Appendix 3.) The Cyclo-Crane is a hybrid aircraft utilizing aerostatic lift from a helium filled centerbody to support

Unique Structural Modifications Are Present in the Lipopolysaccharide from Colistin-Resistant Strains of Acinetobacter baumannii

DTIC Science & Technology

2013-10-01

13). Freeze-dried bacteria were resuspended in endotoxin -free water at a concentration of 10 mg/ml. A 12.5-ml volume of 90% phenol was added, and the...temperature for 30 min. The aqueous phase was collected, and an equal volume of endotoxin -free water was added to the organic phase. The sample was...The resultant pel- let was resuspended at a concentration of 10 mg/ml in endotoxin -free water, treated with DNase (Sigma, St. Louis, MO) at 100 g/ml

What are the correct ρ0(770 ) meson mass and width values?

NASA Astrophysics Data System (ADS)

Bartoš, Erik; Dubnička, Stanislav; Liptaj, Andrej; Dubničková, Anna Zuzana; Kamiński, Robert

2017-12-01

The accuracy of the Gounaris-Sakurai pion electromagnetic form factor model at the elastic region, in which just the ρ0(770 ) resonance appears, is investigated by the particular analysis of the most accurate P-wave isovector π π scattering phase shift δ11(t ) data, obtained by the Garcia-Martin-Kamiński-Peláez-Yndurain approach, and by an application of the Unitary&Analytic pion electromagnetic structure model to a description of the newest precise data on the e+e-→π+π- process.

What can 35 years and over 700,000 measurements tell us about noise exposure in the mining industry?

PubMed

Roberts, Benjamin; Sun, Kan; Neitzel, Richard L

2017-01-01

To analyse over 700,000 cross-sectional measurements from the Mine Safety and Health Administration (MHSA) and develop statistical models to predict noise exposure for a worker. Descriptive statistics were used to summarise the data. Two linear regression models were used to predict noise exposure based on MSHA-permissible exposure limit (PEL) and action level (AL), respectively. Twofold cross validation was used to compare the exposure estimates from the models to actual measurement. The mean difference and t-statistic was calculated for each job title to determine whether the model predictions were significantly different from the actual data. Measurements were acquired from MSHA through a Freedom of Information Act request. From 1979 to 2014, noise exposure has decreased. Measurements taken before the implementation of MSHA's revised noise regulation in 2000 were on average 4.5 dBA higher than after the law was implemented. Both models produced exposure predictions that were less than 1 dBA different than the holdout data. Overall noise levels in mines have been decreasing. However, this decrease has not been uniform across all mining sectors. The exposure predictions from the model will be useful to help predict hearing loss in workers in the mining industry.

Heavy construction equipment noise study using dosimetry and time-motion studies

NASA Astrophysics Data System (ADS)

Spencer, Ellsworth R.; Yantek, David S.

2005-09-01

Noise-induced hearing loss continues to afflict workers in many occupational settings despite longstanding recognition of the problems and well-known methods of prevention and regulations. Sound levels associated with heavy construction equipment range from 80 to 120 dB(A) and power tools commonly used in construction produce sound levels up to 115 dB(A). The focus of the research was to determine the noise exposures of heavy construction equipment operators while documenting the workers' tasks, (i.e., hauling, moving, and/or pushing construction material). Time-motion studies were performed at the construction sites and were used to correlate the noise dosage with the work performed by equipment operators. The cumulative dose for the operator was then plotted with references to work tasks, to identify the tasks that caused the greatest noise exposure. Three construction sites were examined and located in the western Pennsylvania and eastern Ohio areas. The types of construction equipment studied included asphalt pavers, backhoes, bulldozers, compaction equipment, excavators, haul trucks, telehandlers, and wheeled loaders. The results showed that bulldozer operators consistently had the highest noise exposures, ranging from a NIOSH REL (Recommended Exposure Limit) dose of 844% to 25836% and an OSHA PEL (Permissible Exposure Limit) dose of 139% to 1397%.

Molecular Determinants of the Thickened Matrix in a Dual-Species Pseudomonas aeruginosa and Enterococcus faecalis Biofilm

PubMed Central

Lee, Keehoon; Lee, Kang-Mu; Kim, Donggeun

2017-01-01

ABSTRACT Biofilms are microbial communities that inhabit various surfaces and are surrounded by extracellular matrices (ECMs). Clinical microbiologists have shown that the majority of chronic infections are caused by biofilms, following the introduction of the first biofilm infection model by J. W. Costerton and colleagues (J. Lam, R. Chan, K. Lam, and J. W. Costerton, Infect Immun 28:546–556, 1980). However, treatments for chronic biofilm infections are still limited to surgical removal of the infected sites. Pseudomonas aeruginosa and Enterococcus faecalis are two frequently identified bacterial species in biofilm infections; nevertheless, the interactions between these two species, especially during biofilm growth, are not clearly understood. In this study, we observed phenotypic changes in a dual-species biofilm of P. aeruginosa and E. faecalis, including a dramatic increase in biofilm matrix thickness. For clear elucidation of the spatial distribution of the dual-species biofilm, P. aeruginosa and E. faecalis were labeled with red and green fluorescence, respectively. E. faecalis was located at the lower part of the dual-species biofilm, while P. aeruginosa developed a structured biofilm on the upper part. Mutants with altered exopolysaccharide (EPS) productions were constructed in order to determine the molecular basis for the synergistic effect of the dual-species biofilm. Increased biofilm matrix thickness was associated with EPSs, not extracellular DNA. In particular, Pel and Psl contributed to interspecies and intraspecies interactions, respectively, in the dual-species P. aeruginosa and E. faecalis biofilm. Accordingly, targeting Pel and Psl might be an effective part of eradicating P. aeruginosa polymicrobial biofilms. IMPORTANCE Chronic infection is a serious problem in the medical field. Scientists have observed that chronic infections are closely associated with biofilms, and the vast majority of infection-causing biofilms are polymicrobial. Many studies have reported that microbes in polymicrobial biofilms interact with each other and that the bacterial interactions result in elevated virulence, in terms of factors, such as infectivity and antibiotic resistance. Pseudomonas aeruginosa and Enterococcus faecalis are frequently isolated pathogens in chronic biofilm infections. Nevertheless, while both bacteria are known to be agents of numerous nosocomial infections and can cause serious diseases, interactions between the bacteria in biofilms have rarely been examined. In this investigation, we aimed to characterize P. aeruginosa and E. faecalis dual-species biofilms and to determine the molecular factors that cause synergistic effects, especially on the matrix thickening of the biofilm. We suspect that our findings will contribute to the development of more efficient methods for eradicating polymicrobial biofilm infections. PMID:28842537

Molecular Determinants of the Thickened Matrix in a Dual-Species Pseudomonas aeruginosa and Enterococcus faecalis Biofilm.

PubMed

Lee, Keehoon; Lee, Kang-Mu; Kim, Donggeun; Yoon, Sang Sun

2017-11-01

Biofilms are microbial communities that inhabit various surfaces and are surrounded by extracellular matrices (ECMs). Clinical microbiologists have shown that the majority of chronic infections are caused by biofilms, following the introduction of the first biofilm infection model by J. W. Costerton and colleagues (J. Lam, R. Chan, K. Lam, and J. W. Costerton, Infect Immun 28:546-556, 1980). However, treatments for chronic biofilm infections are still limited to surgical removal of the infected sites. Pseudomonas aeruginosa and Enterococcus faecalis are two frequently identified bacterial species in biofilm infections; nevertheless, the interactions between these two species, especially during biofilm growth, are not clearly understood. In this study, we observed phenotypic changes in a dual-species biofilm of P. aeruginosa and E. faecalis , including a dramatic increase in biofilm matrix thickness. For clear elucidation of the spatial distribution of the dual-species biofilm, P. aeruginosa and E. faecalis were labeled with red and green fluorescence, respectively. E. faecalis was located at the lower part of the dual-species biofilm, while P. aeruginosa developed a structured biofilm on the upper part. Mutants with altered exopolysaccharide (EPS) productions were constructed in order to determine the molecular basis for the synergistic effect of the dual-species biofilm. Increased biofilm matrix thickness was associated with EPSs, not extracellular DNA. In particular, Pel and Psl contributed to interspecies and intraspecies interactions, respectively, in the dual-species P. aeruginosa and E. faecalis biofilm. Accordingly, targeting Pel and Psl might be an effective part of eradicating P. aeruginosa polymicrobial biofilms. IMPORTANCE Chronic infection is a serious problem in the medical field. Scientists have observed that chronic infections are closely associated with biofilms, and the vast majority of infection-causing biofilms are polymicrobial. Many studies have reported that microbes in polymicrobial biofilms interact with each other and that the bacterial interactions result in elevated virulence, in terms of factors, such as infectivity and antibiotic resistance. Pseudomonas aeruginosa and Enterococcus faecalis are frequently isolated pathogens in chronic biofilm infections. Nevertheless, while both bacteria are known to be agents of numerous nosocomial infections and can cause serious diseases, interactions between the bacteria in biofilms have rarely been examined. In this investigation, we aimed to characterize P. aeruginosa and E. faecalis dual-species biofilms and to determine the molecular factors that cause synergistic effects, especially on the matrix thickening of the biofilm. We suspect that our findings will contribute to the development of more efficient methods for eradicating polymicrobial biofilm infections. Copyright © 2017 American Society for Microbiology.

A comprehensive assessment of exposures to respirable dust and silica in the taconite mining industry.

PubMed

Hwang, Jooyeon; Ramachandran, Gurumurthy; Raynor, Peter C; Alexander, Bruce H; Mandel, Jeffrey H

2017-05-01

This study assessed the present-day levels (year 2010-2011) of exposure to respirable dust (RD) and respirable silica (RS) in taconite mines and evaluated how the mining process influences exposure concentrations. Personal samples (n = 679) were collected to assess exposure levels of workers to RD and RS at six mines in the Mesabi Iron Range of Minnesota. The RD and RS concentrations were measured using the National Institute for Occupational Safety and Health (NIOSH) 0600 and NIOSH 7500, respectively. Between-mine, between-SEG (similar exposure groups), within-SEG, and within-worker components of variability for RD and RS exposures were estimated using a two- or three-way nested random-effects ANOVA model. The majority of RD concentrations across all mines were below the Mine Safety and Health Administration (MSHA) Permissible Exposure Limit (PEL). The highest concentrations of RD were often observed in either the Pelletizing or Crushing departments, which are inherently dusty operations. With a few exceptions, the concentrations of RS in the crushing and concentrating processes were higher than those in the other mining processes, as well as higher than the American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV) for RS. The magnetic separation and flotation processes in the concentrating department reduced the levels of RS significantly, and lowered the percentage of quartz in RD in the pelletizing department. There was little variability among the six mines or between the two mineralogically distinct zones for either RD or RS exposures. The between-SEG variability for RS did not differ substantially across most of the mines and was a major component of exposure variance. The within-SEG (or between-worker) variance component was typically the smallest because in many instances one worker from a SEG within a mine was monitored multiple times. Some of these findings were affected by the degree of censoring in each SEG and mine, characteristics of the taconite rock, seasonal effects during sampling, or the tasks assigned to each job in that mine.

Flavoring exposure in food manufacturing

PubMed Central

Curwin, Brian D.; Deddens, Jim A.; McKernan, Lauralynn T.

2015-01-01

Flavorings are substances that alter or enhance the taste of food. Workers in the food-manufacturing industry, where flavorings are added to many products, may be exposed to any number of flavoring compounds. Although thousands of flavoring substances are in use, little is known about most of these in terms of worker health effects, and few have occupational exposure guidelines. Exposure assessment surveys were conducted at nine food production facilities and one flavor manufacturer where a total of 105 area and 74 personal samples were collected for 13 flavoring compounds including five ketones, five aldehydes, and three acids. The majority of the samples were below the limit of detection (LOD) for most compounds. Diacetyl had eight area and four personal samples above the LOD, whereas 2,3-pentanedione had three area samples above the LOD. The detectable values ranged from 25–3124 ppb and 15–172 ppb for diacetyl and 2,3-pentanedione respectively. These values exceed the proposed National Institute for Occupational Safety and Health (NIOSH) recommended exposure limit for these compounds. The aldehydes had the most detectable samples, with each of them having >50% of the samples above the LOD. Acetaldehyde had all but two samples above the LOD, however, these samples were below the OSHA PEL. It appears that in the food-manufacturing facilities surveyed here, exposure to the ketones occurs infrequently, however levels above the proposed NIOSH REL were found. Conversely, aldehyde exposure appears to be ubiquitous. PMID:25052692

Ecotoxicological and Health Risk Assessment of Polycyclic Aromatic Hydrocarbons (PAHs) in Short-Neck Clam (Paphia undulata) and Contaminated Sediments in Malacca Strait, Malaysia.

PubMed

Keshavarzifard, Mehrzad; Zakaria, Mohamad Pauzi; Sharifi, Reza

2017-10-01

The distribution, sources, and human health risk assessment of polycyclic aromatic hydrocarbons (PAHs) in surface sediment and the edible tissue of short-neck clam (Paphia undulata) from mudflat ecosystem in the west coast of Malaysia were investigated. The concentrations of ∑ 16 PAHs varied from 347.05 to 6207.5 and 179.32 to 1657.5 ng g -1 in sediment and short-neck clam samples, respectively. The calculations of mean PEL quotients (mean-PELQs) showed that the ecological risk of PAHs in the sediment samples was low to moderate-high level, whereas the total health risk through ingestion and dermal contact was considerably high. The PAHs biota sediment accumulation factors data for short-neck clam were obtained in this study, indicating a preferential accumulation of lower molecular weight PAHs. The source apportionment of PAHs in sediment using positive matrix factorization model indicated that the highest contribution to the PAHs was from diesel emissions (30.38%) followed by oil and oil derivate and incomplete coal combustion (23.06%), vehicular emissions (16.43%), wood combustion (15.93%), and natural gas combustion (14.2%). A preliminary evaluation of human health risk using chronic daily intake, hazard index, benzo[a]pyrene-equivalent (BaP eq ) concentration, and the incremental lifetime cancer risk indicated that PAHs in short-neck clam would induce potential carcinogenic effects in the consumers.

DDT Analysis of Wetland Sediments in Upper Escambia Bay, Florida

NASA Astrophysics Data System (ADS)

Hopko, M. N.; Wright, J.; Liebens, J.; Vaughan, P.

2017-12-01

Dichlorodiphenyltrichloroethane (DDT) was a commonly used pesticide from World War II through the 1960's. DDT is generally used to control mosquito populations and as an agricultural insecticide. The pesticide and its degradation products (DDD and DDE) can bioaccumulate within ecosystems having negative implications for animal and human health. Consequently, DDT usage was banned in the United States in 1973. In a contaminant study performed in Escambia Bay, Florida, in 2009, DDT was present in 25% of study sites, most of which were located in the upper bay wetlands. Concentrations were well above the Florida Department of Environmental Protection's (FDEP) Probable Effect Level (PEL) and ratios of DDT and its metabolites indicated a recent introduction to the system. A follow-up study performed in 2016 found no DDT, but did show DDE at several sites. The current study repeated sampling in May 2017 at sites from the 2009 and 2016 studies. Sediment samples were collected in triplicate using a ponar sampler and DDT, DDD and DDE were extracted using EPA methods 3540c and 3620c. Extracts were analyzed using a gas chromatograph with electron capture detection (GC-ECD) as per EPA method 8081c. Sediment was also analyzed for organic carbon and particle size using an elemental NC analyzer and a laser diffraction particle sizer. Results show the presence of breakdown products DDE and DDD at multiple sites, but no detectable levels of DDT at any site. Sampling sites with high levels of DDT contamination in 2009 show only breakdown products in both 2016 and 2017. Particle size has little influence on DDD or DDE concentrations but OC is a controlling factor as indicated for contaminated sites by Pearson correlations between OC and DDE and DDD of 0.82 and 0.92, respectively. The presence of only DDD and/or DDE in the 2016 and 2017 studies indicates that the parent, DDT, has not been re-introduced into the watershed since 2009 but is degrading in the environment.

KSHV-associated multicentric Castleman disease: A tangle of different entities requiring multitarget treatment strategies.

PubMed

Carbone, Antonino; De Paoli, Paolo; Gloghini, Annunziata; Vaccher, Emanuela

2015-07-15

Multicentric Castleman Disease (MCD) is a lymphoproliferative disorder presenting with heterogeneous pathological and clinical features. It comprises disease entities with a complex aetiology and overlapping pathogenesis. MCD can be found in association with HIV infection, plasma-cell dyscrasias, Kaposi sarcoma (KS), B-cell lymphomas including primary effusion lymphoma (PEL) and its solid variant, and Hodgkin lymphoma. In KSHV-associated MCD cases, a common association is KS and a specific variant of lymphoma referred to as "plasmablastic lymphoma," also called "large B-cell lymphoma arising in KSHV-associated MCD" lacking EBV infection. MCD is often referred to as human interleukin-6 (hIL-6) syndrome, since an overproduction of IL-6 occurs in MCD-associated diseases as well as in MCD itself. hIL-6 and a viral IL-6 (vIL-6) homolog encoded by KSHV can independently or together lead to flares of KSHV-associated MCD. Recently, a new clinical entity was proposed to describe a severe systemic infection/reactivation of KSHV: KSHV inflammatory syndrome (KICS). KICS may contribute in inducing the inflammatory symptoms seen in some patients with severe KS or PEL. The precise relationship of KICS to KSHV-associated MCD is unclear and it is possible that KICS may be prodromal symptoms to frank KSHV-associated MCD. Options for treatment of KSHV-associated MCD and related diseases include monoclonal antibodies, chemotherapy, immune modulators, virus-activated cytotoxic therapy and antiviral therapies. A comprehensive understanding of the intricacies of the HIV-KSHV coinfection will probably lead to additional advances in therapy and managements for these disorders. © 2014 UICC.

Ecological risk assessment of the Assaluyeh and Bassatin estuaries (northern Persian Gulf) using sediment quality indices

NASA Astrophysics Data System (ADS)

Davoodi, Hamid; Gharibreza, Mohammadreza; Negarestan, Hossein; Mortazavi, Mohammad Sedigh; Lak, Razieh

2017-06-01

The Assaluyeh and Bassatin estuaries are located in Nayband Bay in the northern Persian Gulf, which faces long-term contamination and ecological risks. The research objectives of this study were designed to assess the ecological risks for human health and aquatic life and to evaluate impacts on environmental changes. Accordingly, an index analysis approach (using the contamination factor Cf, contamination degree Cd, potential ecological risk factor for individual metals Er, and potential ecological risk index for the basin, RI) in conjunction with the enrichment factor (Ef) and sediment quality levels (comprised of the threshold effect level, TEL, the probable effect level, PEL, and the effects range medium, ERM) were employed. In total, 147 sediment samples were tested to determine the content of organic matter and sulfur, as well as the concentrations of terrestrial and rare earth elements (REEs) and toxic metals, namely As, Cd, Cr, Cu, Ni and Hg, using inductively coupled plasma optical emission spectroscopy (ICP-OES). Gulf War oil spills in addition to oil and gas industries of the Pars South Especial Economic Zone (PSEEZ) were identified as the primary source of pollution in the study area. Gulf War contamination in the study area is highlighted by increased levels of Cd and RI at key horizons at 29 cm, 35 cm and 49 cm depth in the sedimentary columns of the Assaluyeh and Bassatin estuaries and Gavbandi River, respectively. Adverse effects of PSEEZ were revealed by increasing concentrations of toxic metals, P and S in the top 25-30 cm of the sedimentary columns. As a result, superficial sediments have been severely polluted by As, Ni, Cd, Cu and Cr, while the entire sedimentary column of the Assaluyeh estuary has been polluted by Hg. Based on the locations of the key horizons, the sedimentation rates of the previous decade at the Assaluyeh and Bassatin estuaries and the Gavbandi River were calculated to be 1.26 cm, 1.52 cm, and 2.13 cm, respectively. The capability of the index analysis approach, as well as of certain lanthanides, for highlighting environmental evolutionary trends in catchments in which extensive land use changes have occurred was demonstrated by the present investigation. The present research concluded that aquatic life and human health in the study area have been subjected to different ranges of hazards by toxic metals due to regional and local anthropogenic activities.

Process development of a human recombinant diabody expressed in E. coli: engagement of CD99-induced apoptosis for target therapy in Ewing's sarcoma.

PubMed

Moricoli, Diego; Carbonella, Damiano Cosimo; Dominici, Sabrina; Fiori, Valentina; Balducci, Maria Cristina; Guerzoni, Clara; Manara, Maria Cristina; Pasello, Michela; Laguardia, Maria Elena; Cianfriglia, Maurizio; Scotlandi, Katia; Magnani, Mauro

2016-05-01

Ewing's sarcoma (EWS) is the second most common primary bone tumor in pediatric patients characterized by over expression of CD99. Current management consists in extensive chemotherapy in addition to surgical resection and/or radiation. Recent improvements in treatment are still overshadowed by severe side effects such as toxicity and risk of secondary malignancies; therefore, more effective strategies are urgently needed. The goal of this work was to develop a rapid, inexpensive, and "up-scalable" process of a novel human bivalent single-chain fragment variable diabody (C7 dAbd) directed against CD99, as a new therapeutic approach for EWS. We first investigated different Escherichia coli constructs of C7 dAbd in small-scale studies. Starting from 60 % soluble fraction, we obtained a yield of 25 mg C7 dAbd per liter of bacterial culture with the construct containing pelB signal sequence. In contrast, a low recovery of C7 dAbd was achieved starting from periplasmic inclusion bodies. In order to maximize the yield of C7 dAbd, large-scale fermentation was optimized. We obtained from 75 % soluble fraction 35 mg C7 dAbd per L of cell culture grown in a synthetic media containing 3 g/L of vegetable peptone and 1 g/L of yeast extract. Furthermore, we demonstrated the better efficacy of the cell lysis by homogenization versus periplasmic extraction, in reducing endotoxin level of the C7 dAbd. For gram-scale purification, a direct aligned two-step chromatography cascade based on binding selectivity was developed. Finally, we recovered C7 dAbd with low residual process-related impurities, excellent reactivity, and apoptotic ability against EWS cells.

Effectiveness evaluation of existing noise controls in a deep shaft underground mine.

PubMed

Lutz, Eric A; Reed, Rustin J; Turner, Dylan; Littau, Sally R; Lee, Vivien; Hu, Chengcheng

2015-01-01

Noise exposures and hearing loss in the mining industry continue to be a major problem, despite advances in noise control technologies. This study evaluated the effectiveness of engineering, administrative, and personal noise controls using both traditional and in-ear dosimetry by job task, work shift, and five types of earplug. The noise exposures of 22 miners performing deep shaft-sinking tasks were evaluated during 56 rotating shifts in an underground mine. Miners were earplug-insertion trained, earplug fit-tested, and monitored utilizing traditional and in-ear dosimetry. The mean TWA8 noise exposure via traditional dosimetry was 90.1 ± 8.2 dBA, while the mean in-ear TWA8 was 79.6 ± 13.8 dBA. The latter was significantly lower (p < 0.05) than the Mine Safety and Health Administration (MSHA) personal exposure limit (PEL) of 90 dBA. Dosimetry mean TWA8 noise exposures for bench blowing (103.5 ± 0.9 dBA), jumbo drill operation (103.0 ± 0.8 dBA), and mucking tasks (99.6 ± 4.7 dBA) were significantly higher (p < 0.05) than other tasks. For bench blowing, cable pulling, grinding, and jumbo drill operation tasks, the mean in-ear TWA8 was greater than 85 dBA. Those working swing shift had a significantly higher (p < 0.001) mean TWA8 noise exposure (95.4 ± 7.3 dBA) than those working day shift. For percent difference between traditional vs. in-ear dosimetry, there was no significant difference among types of earplug used. Reflective of occupational hearing loss rate trends across the mining industry, this study found that, despite existing engineering and administrative controls, noise exposure levels exceeded regulatory limits, while the addition of personal hearing protection limited excessive exposures.

Role of psl Genes in Antibiotic Tolerance of Adherent Pseudomonas aeruginosa.

PubMed

Murakami, Keiji; Ono, Tsuneko; Viducic, Darija; Somiya, Yoko; Kariyama, Reiko; Hori, Kenji; Amoh, Takashi; Hirota, Katsuhiko; Kumon, Hiromi; Parsek, Matthew R; Miyake, Yoichiro

2017-07-01

Bacteria attached to a surface are generally more tolerant to antibiotics than their planktonic counterparts, even without the formation of a biofilm. The mechanism of antibiotic tolerance in biofilm communities is multifactorial, and the genetic background underlying this antibiotic tolerance has not yet been fully elucidated. Using transposon mutagenesis, we isolated a mutant with reduced tolerance to biapenem (relative to that of the wild type) from adherent cells. Sequencing analysis revealed a mutation in the pslL gene, which is part of the polysaccharide biosynthesis operon. The Pseudomonas aeruginosa PAO1Δ pslBCD mutant demonstrated a 100-fold-lower survival rate during the exposure of planktonic and biofilm cells to biapenem; a similar phenotype was observed in a mouse infection model and in clinical strains. Transcriptional analysis of adherent cells revealed increased expression of both pslA and pelA , which are directly regulated by bis-(3',5')-cyclic dimeric GMP (c-di-GMP). Inactivation of wspF resulted in significantly increased tolerance to biapenem due to increased production of c-di-GMP. The loss of pslBCD in the Δ wspF mutant background abolished the biapenem-tolerant phenotype of the Δ wspF mutant, underscoring the importance of psl in biapenem tolerance. Overexpression of PA2133, which can catalyze the degradation of c-di-GMP, led to a significant reduction in biapenem tolerance in adherent cells, indicating that c-di-GMP is essential in mediating the tolerance effect. The effect of pslBCD on antibiotic tolerance was evident, with 50- and 200-fold-lower survival in the presence of ofloxacin and tobramycin, respectively. We speculate that the psl genes, which are activated by surface adherence through elevated intracellular c-di-GMP levels, confer tolerance to antimicrobials. Copyright © 2017 American Society for Microbiology.

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DTIC Science & Technology

2014-07-20

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An adaptive DPCM encoder for NTSC composite video signals

NASA Astrophysics Data System (ADS)

Cox, N. R.

An adaptive DPCM algorithm is proposed for encoding digitized National Television Systems Committee (NTSC) color video signals. This algorithm essentially predicts picture contours in the composite signal without resorting to component separation. Preliminary subjective and objective tests performed on an experimental encoder/simulator indicate that high quality color pictures can be encoded at 4.0 bits/pel or 42.95 Mbit/s. This requires the use of a 4/8 bit dual-word-length coder and buffer memory. Such a system might be useful in certain short hop applications if both large-signal and small-signal responses can be preserved.

Amino acid sequence of a trypsin inhibitor from a Spirometra (Spirometra erinaceieuropaei).

PubMed

Sanda, A; Uchida, A; Itagaki, T; Kobayashi, H; Inokuchi, N; Koyama, T; Iwama, M; Ohgi, K; Irie, M

2001-12-01

A trypsin inhibitor that is highly homologous with bovine pancreatic trypsin inhibitor (BPTI) was co-purified along with RNase from Spirometra (Spirometra erinaceieuropaei). The amino acid sequence of this inhibitor (SETI) and the nucleotide sequence of the cDNA encoding this protein were determined by protein chemistry and gene technology. SETI contains 68 amino acid residues and has a molecular mass of 7,798 Da. SETI has 31 amino acid residues that are identical with BPTI's sequence, including 6 half-cystine and 5 aromatic amino acid residues. The active site Lys residue in BPTI is replaced by an Arg residue in SETI. SETI is an effective inhibitor of trypsin and moderately inhibits a-chymotrypsin, but less inhibits elastase or subtilisin. SETI was expressed by E. coli containing a PelB vector carrying the SETI encoding cDNA; an expression yield of 0.68 mg/l was obtained. The phylogenetic relationship of SETI and the other BPTI-like trypsin inhibitors was analyzed using most likelihood inference methods.

Assessment of heavy metals contamination in soil profiles of roadside Suaeda salsa wetlands in a Chinese delta

NASA Astrophysics Data System (ADS)

Wen, Xiaojun; Wang, Qinggai; Zhang, Guangliang; Bai, Junhong; Wang, Wei; Zhang, Shuai

2017-02-01

Five sampling sites (Sites A, B, C, D and E) were selected along a 250 m sampling zone covered by Suaeda salsa, which is perpendicular to a road, in the Yellow River Delta of China. Soil samples were collected to a depth of 40cm in these five sampling sites to investigate the profile distributions and toxic risks of heavy metals. Concentrations of heavy metals (As, Cd, Cr, Cu, Ni, Pb and Zn) were determined using inductively coupled plasma atomic absorption spectrometry (ICP-AAS). The results showed that in each sampling site, Cd, Cu, Pb and Zn have approximately constant concentrations along soil profiles and did not show high contamination compared with the values of probable effect levels (PELs). All soils exhibited As and Ni contamination at all sampling sites compared with other heavy metals. The index of geo-accumulation (Igeo) values for As in the 20-30 cm soil layer at Site B was grouped into Class Ⅳ(2 < Igeo ≤ 3), indicating that the soil was moderately to strongly contaminated. Forty percent of Igeo values of Cd for all soil samples were grouped into Class Ⅳ(2 < Igeo ≤ 3) and 75% samples of Site C showed moderately to strongly contaminated level. The Enrichment factor (EF) values of As at Sites B, C, D and E reached significant enrichment level and EF values of Cd at five sampling sites all reached significant enrichment level. The sum of toxic units (∑TUs) values for surface soils of Sites B and C beyond 4 indicated that Sites B and C have severer toxicity compared with other three sampling sites. As and Ni should be paid more attention to avoid potential ecotoxicity due to their high contribution ratios to the ∑TUs in Suaeda salsa wetlands. Correlation analysis (CA) and principal components analysis (PCA) revealed that Cr, Cu, Ni, Pb and Zn might derive from the common sources, Cd might originate from another, while As might have more complex sources in this study area.

Relations of benthic macroinvertebrates to concentrations of trace elements in water, streambed sediments, and transplanted bryophytes and stream habitat conditions in nonmining and mining areas of the upper Colorado River basin, Colorado, 1995-98

USGS Publications Warehouse

Mize, Scott V.; Deacon, Jeffrey R.

2002-01-01

Intensive mining activity and highly mineralized rock formations have had significant impacts on surface-water and streambed-sediment quality and aquatic life within the upper reaches of the Uncompahgre River in western Colorado. A synoptic study by the U.S. Geological Survey National Water-Quality Assessment Program was completed in the upper Uncompahgre River Basin in 1998 to better understand the relations of trace elements (with emphasis on aluminum, arsenic, copper, iron, lead, and zinc concentrations) in water, streambed sediment, and aquatic life. Water-chemistry, streambed-sediment, and benthic macroinvertebrate samples were collected during low-flow conditions between October 1995 and July 1998 at five sites on the upper Uncompahgre River, all downstream from historical mining, and at three sites in drainage basins of the Upper Colorado River where mining has not occurred. Aquatic bryophytes were transplanted to all sites for 15 days of exposure to the water column during which time field parameters were measured and chemical water-quality and benthic macroinvertebrate samples were collected. Stream habitat characteristics also were documented at each site. Certain attributes of surface-water chemistry among streams were significantly different. Concentrations of total aluminum, copper, iron, lead, and zinc in the water column and concentrations of dissolved aluminum, copper, and zinc were significantly different between nonmining and mining sites. Some sites associated with mining exceeded Colorado acute aquatic-life standards for aluminum, copper, and zinc and exceeded Colorado chronic aquatic-life standards for aluminum, copper, iron, lead, and zinc. Concentrations of copper, lead, and zinc in streambed sediments were significantly different between nonmining and mining sites. Generally, concentrations of arsenic, copper, lead, and zinc in streambed sediments at mining sites exceeded the Canadian Sediment Quality Guidelines probable effect level (PEL), except at two mining sites where concentrations of copper and zinc were below the PEL. Concentrations of arsenic, copper, iron, and lead in transplanted bryophytes were significantly different between nonmining and mining sites. Bioconcentration factors calculated for 15-day exposure using one-half of the minimum reporting level were significantly different between nonmining and mining sites. In general, concentrations of trace elements in streambed sediment and transplanted bryophytes were more closely correlated than were the concentrations of trace elements in the water column with streambed sediments or concentrations in the water column with transplanted bryophytes. Stream habitat was rated as optimal to suboptimal using the U.S. Environmental Protection Agency Rapid Bioassessment Protocols for all sites in the study area. Generally, stream habitat conditions were similar at nonmining compared to mining sites and were suitable for diverse macroinvertebrate communities. All study sites had optimal instream habitat except two mining sites with suboptimal instream habitat because of disturbances in stream habitat. The benthic macroinvertebrate community composition at nonmining sites and mining sites differed. Mining sites had significantly lower total abundance of macroinvertebrates, fewer numbers of taxa, and lower dominance of Ephemeroptera (mayflies), Plecoptera (stoneflies), and Trichoptera (caddisflies), and a larger percentage of tolerant species than did nonmining sites. The predominance of Baetis sp. (mayflies), Hydropsychidae (caddisflies), and large percentage of Orthocladiinae chironomids (midges) at mining sites indicated that these species may be tolerant to elevated trace-element concentrations. The absence of Heptageniidae (mayflies), Chloroperlidae (stoneflies), and Rhyacophila sp. (caddisflies) at mining sites indicated that these species may be sensitive to elevated trace-element concentrations. Comparison of field parameters and

The Past 20,000 Years of Plinian Explosive Activity at Mt Pelée Volcano (Lesser Antilles)

NASA Astrophysics Data System (ADS)

Carazzo, G.; Michaud-Dubuy, A.; Kaminski, E. C.; Tait, S.

2017-12-01

Major volcanic hazards in the Lesser Antilles arc include powerful Plinian explosive eruptions that inject ash into the atmosphere and produce dangerous pyroclastic density currents (PDC) on the ground. Reconstructions of past eruptive activities based on stratigraphic records are crucial to assessing specific hazards in this region where large eruptions do not occur frequently. The present study focuses on the dynamics of the last Plinian eruptions of Mount Pelée volcano in Martinique. Previous field-based studies identified 6 major Plinian eruptions over the past 5,000 years but limited information on their dynamics exist, except for the most recent one dated at AD 1300. Based on a new comprehensive field study and physical models of volcanic plumes, we largely improve our knowledge of the number of Plinian eruptions that occurred in Martinique over the past 20,000 years. We also provide a detailed reconstruction of important eruptive parameters such as mass eruption rates, maximum column heights, volumes, and impacted areas. Among the 6 Plinian eruptions newly identified during our field campaign, one is found to have produced voluminous pyroclastic density currents that reached the sea and partially rose as a co-PDC plume above a region that is beyond the existing hazard map. The estimated mass eruption rates for the 12 Plinian eruptions identified over the last 20,000 years range from 107 to 108 kg/s, producing 15-30 km-high Plinian columns, initially stable but ultimately collapsing and forming PDC. Empirical models of deposit thinning suggest that the minimum volume of pyroclastic deposits systematically ranges between 0.1 and 1 km3, corresponding to VEI 4 to 5 events. Archaeological evidences suggest that the impact of several eruptions forced the first Caribbean inhabitants to flee to other islands for decades.

Jasmonate-dependent modifications of the pectin matrix during potato development function as a defense mechanism targeted by Dickeya dadantii virulence factors.

PubMed

Taurino, Marco; Abelenda, Jose A; Río-Alvarez, Isabel; Navarro, Cristina; Vicedo, Begonya; Farmaki, Theodora; Jiménez, Pedro; García-Agustín, Pilar; López-Solanilla, Emilia; Prat, Salomé; Rojo, Enrique; Sánchez-Serrano, José J; Sanmartín, Maite

2014-02-01

The plant cell wall constitutes an essential protection barrier against pathogen attack. In addition, cell-wall disruption leads to accumulation of jasmonates (JAs), which are key signaling molecules for activation of plant inducible defense responses. However, whether JAs in return modulate the cell-wall composition to reinforce this defensive barrier remains unknown. The enzyme 13-allene oxide synthase (13-AOS) catalyzes the first committed step towards biosynthesis of JAs. In potato (Solanum tuberosum), there are two putative St13-AOS genes, which we show here to be differentially induced upon wounding. We also determine that both genes complement an Arabidopsis aos null mutant, indicating that they encode functional 13-AOS enzymes. Indeed, transgenic potato plants lacking both St13-AOS genes (CoAOS1/2 lines) exhibited a significant reduction of JAs, a concomitant decrease in wound-responsive gene activation, and an increased severity of soft rot disease symptoms caused by Dickeya dadantii. Intriguingly, a hypovirulent D. dadantii pel strain lacking the five major pectate lyases, which causes limited tissue maceration on wild-type plants, regained infectivity in CoAOS1/2 plants. In line with this, we found differences in pectin methyl esterase activity and cell-wall pectin composition between wild-type and CoAOS1/2 plants. Importantly, wild-type plants had pectins with a lower degree of methyl esterification, which are the substrates of the pectate lyases mutated in the pel strain. These results suggest that, during development of potato plants, JAs mediate modification of the pectin matrix to form a defensive barrier that is counteracted by pectinolytic virulence factors from D. dadantii. © 2013 The Authors The Plant Journal © 2013 John Wiley & Sons Ltd.

EBV-associated but HHV8-unrelated double-hit effusion-based lymphoma.

PubMed

Chen, Bo-Jung; Chen, David Yen-Ting; Kuo, Chun-Chi; Chuang, Shih-Sung

2017-03-01

Effusion-based lymphoma is a rare and unique type of large B-cell lymphoma presenting in effusion without a mass lesion. It shares many clinicopathological features with primary effusion lymphoma (PEL), but is distinct from PEL by the absence of HHV8 association. Double hit lymphoma (DHL) is an aggressive B-cell lymphoma, defined by concurrent rearrangement of MYC and BCL2 or BCL6. DHL often presents as lymphadenopathy or an extranodal mass, but rarely occurs in effusion. Here we report a 61-year-old male with alcoholic cirrhosis presenting as massive ascites and left pleural effusion. He has no HIV, HBV or HCV infection and no mass lesion by CT scans. Cytology of both pleural effusion and ascites show large lymphoma cells with plasmablastic morphology characterized by pleomorphic and eccentric nuclei, prominent nucleoli and frequent mitoses. Immunohistochemical study with cell block shows that the lymphoma cells express plasma cell-related markers (CD138, MUM-1 and EMA), but not CD3, CD30, CD45, B-cell markers (CD19, CD20, CD79a, and PAX5), HHV8, ALK or cytokeratin. EBER is positive in most lymphoma cells. Fluorescence in situ hybridization reveals rearrangement at the IGH, BCL2, and MYC loci, but not at BCL6. It is diagnosed as an EBV-associated but HHV8-unrelated double hit effusion-based lymphoma with plasmablastic features. The patient passed away soon after diagnosis without chemotherapy. This is the first reported case of double-hit effusion-based lymphoma with MYC and BCL2 rearrangement. This case illustrates the importance of integrating clinical, cytological, immunophenotypical, and molecular findings to reach a correct diagnosis. Diagn. Cytopathol. 2017;45:257-261. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Development of Fly Ash-Based Sorbent to Capture CO2 from Flue Gas

NASA Astrophysics Data System (ADS)

Majchrzak-Kucęba, I.; Nowak, W.

In the present work the thermogravimetric characterization of the sorption of carbon dioxide on polymer-modifiedmesoporous materials (MCM-41) from fly ashes is described. In order to obtain MCM-41 materials from three different types fly ashes,(including CFB fly ash) hydrothermal processesusing the supernatantsof coal fly ashes and surfactantsas the structure-directing agents,have been carried out. The obtained mesoporous materials were subjected to polyethylenimine (PEI) modification by their impregnation to obtain samples with PEl contents of 30, 50 and 70%, respectively. CO2 sorption/desorption tests on loaded PEl samples were carried out in a flow of a mixture of gasses (CO2-1O%, O2-10%, N2-80%) at different temperatures: 25 and 75°C. The highest CO2 sorption value was obtained for the sample that contained the best-quality MCM-41 and was impregnatedwith PEI in the amount of 50%. This sample at a temperatureof 75°C can take CO2 in an amount equivalent to 111.7 mgCO2/g sample weight. Under the same conditions, but without PEI impregnation, this sample can take CO2 in an amount equivalent to 3.2 mgCO2/g sample weight, thus 35 times less. The research of CO2 adsorption on polymer-modified mesoporous materials from fly ashes carried out within this work has shown that these materials are characterized by high CO2 adsorption capacity under conditions typical of coal combustionboiler flue gas and have the chance of becoming an efficient adsorbent for application to post-combustion CO2 separation. For PEI impregnated samples, a different behaviour of adsorption/desorption profiles has also been observed (both sorption and desorptionprogressesvery rapidly).

Antimicrobial activity of yeasts against some pathogenic bacteria

PubMed Central

Younis, Gamal; Awad, Amal; Dawod, Rehab E.; Yousef, Nehal E.

2017-01-01

Aim: This study was designed to isolate and identify yeast species from milk and meat products, and to test their antimicrobial activity against some bacterial species. Materials and Methods: A total of 160 milk and meat products samples were collected from random sellers and super markets in New Damietta city, Damietta, Egypt. Samples were subjected to yeast isolation procedures and tested for its antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. In addition, all yeast species isolates were subjected to polymerase chain reaction (PCR) for detection of khs (kievitone hydratase) and pelA (pectate degrading enzyme)genes. Results: The recovery rate of yeasts from sausage was 20% (2/10) followed by kareish cheese, processed cheese, and butter 10% (1/10) each as well as raw milk 9% (9/100), and fruit yoghurt 30% (6/20). Different yeast species were recovered, namely, Candida kefyr (5 isolates), Saccharomyces cerevisiae (4 isolates), Candida intermedia (3 isolates), Candida tropicalis (2 isolates), Candida lusitaniae (2 isolates), and Candida krusei (1 isolate). khs gene was detected in all S. cerevisiae isolates, however, pelA gene was not detected in all identified yeast species. Antimicrobial activity of recovered yeasts against the selected bacterial species showed high activity with C. intermedia against S. aureus and E. coli, C. kefyr against E. coli, and C. lusitaniae against S. aureus. Moderate activities were obtained with C. tropicalis, C. lusitaniae, and S. cerevisiae against E. coli; meanwhile, all the tested yeasts revealed a very low antimicrobial activity against P. aeruginosa. Conclusion: The obtained results confirmed that some kinds of yeasts have the ability to produce antimicrobial compounds that could inhibit some pathogenic and spoilage bacteria and these antimicrobial activity of yeasts enables them to be one of the novel agents in controlling spoilage of food. PMID:28919693

Spatial variability of metal bioaccumulation in estuarine killifish (Fundulus heteroclitus) at the Callahan Mine Superfund site, Brooksville, ME

PubMed Central

Buckman, Kate L.; Bugge, Deenie M.; Chen, Celia Y.

2013-01-01

The former Callahan Mine Site in Brooksville, ME is an open-pit, hardrock mine site in an intertidal system, providing a unique opportunity to evaluate how metal-enriched sediments and overlying water impact estuarine food webs. Cu, Zn, Cd, and Pb concentrations in sediment, whole water, and Atlantic killifish (Fundulus heteroclitus) were evaluated at sites in Goose Pond (the Callahan Mine Site) and at reference sites. The metal concentrations of sediment, water, and fish were spatially distinct and significantly higher at the Mine Site than in the reference estuary. Sediment concentrations were particularly elevated and were above probable effects levels (PEL) for all four metals adjacent to the tailings pile. Even in this well-mixed system, water metal concentrations were significantly elevated adjacent to the tailings pile and the concentrations of Cu and Zn were above ambient water quality criteria (AWQC) for chronic marine exposure. Neither organic matter in the sediment nor salinity or pH of the water explained the metal concentrations. Adjacent to the tailings pile, killifish body burdens were elevated and were significantly related to both sediment and aqueous concentrations. In conclusion, (1) the contaminated sediment and seepage from the tailings impoundment and waste rock pile 3 create a continual flux of metals into the water column, (2) the metals are bioavailable and are bioconcentrating as evident in the killifish tissue concentrations, and (3) Callahan Mine is directly affecting metal bioaccumulation in fauna residing in the Goose Pond estuary and, potentially, in Penobscot Bay via the ‘trophic nekton relay.’ PMID:24022459

Health-hazard evaluation report HETA 91-298-2182, Gibson Flatiron, Erica Shell Manufacturing, Bozeman, Montana

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

McCammon, C.S.

1992-02-01

In response to a request from the Montana State Health Department, an evaluation was undertaken of exposures to wood dust and lacquer vapors at the Gibson Flatiron/Erica Shell Manufacturing Companies (SIC-3931), Bozeman, Montana. Gibson Flatiron manufactured mandolins and banjoes. Erica Shell Manufacturing Company cuts and grinds abalone and other sea shells into small pieces to be used in designs inlayed into mandolins and banjos. Measured wood dust levels ranged from 0.8 to 32mg/cu m with an 8 hour time weighted average (TWA) of 1.2 to 30mg/cu m. Rib construction and assembly, and planing bulk ebony wood had TWA exposures abovemore » the OSHA permissible exposure limit of 5mg/cu m for wood dust. Application of dyes and finishes resulted in low exposures to acetone (67641), toluene (108883), xylene (1330207), and butyl-acetate (123864). No solvent air concentrations were above 10% of their respective PELs. The author concludes that a health hazard existed for exposure to wood dusts. The author recommends the establishment of a respiratory protection program and a hearing conservation program. Emergency egress routes should be marked in the buildings.« less

Combating speckle in SAR images - Vector filtering and sequential classification based on a multiplicative noise model

NASA Technical Reports Server (NTRS)

Lin, Qian; Allebach, Jan P.

1990-01-01

An adaptive vector linear minimum mean-squared error (LMMSE) filter for multichannel images with multiplicative noise is presented. It is shown theoretically that the mean-squared error in the filter output is reduced by making use of the correlation between image bands. The vector and conventional scalar LMMSE filters are applied to a three-band SIR-B SAR, and their performance is compared. Based on a mutliplicative noise model, the per-pel maximum likelihood classifier was derived. The authors extend this to the design of sequential and robust classifiers. These classifiers are also applied to the three-band SIR-B SAR image.

Tracking Pyroclastic Flows at Soufrière Hills Volcano

NASA Astrophysics Data System (ADS)

Ripepe, Maurizio; De Angelis, Silvio; Lacanna, Giorgio; Poggi, Pasquale; Williams, Carlisle; Marchetti, Emanuele; Delle Donne, Dario; Ulivieri, Giacomo

2009-07-01

Explosive volcanic eruptions typically show a huge column of ash and debris ejected into the stratosphere, crackling with lightning. Yet equally hazardous are the fast moving avalanches of hot gas and rock that can rush down the volcano's flanks at speeds approaching 280 kilometers per hour. Called pyroclastic flows, these surges can reach temperatures of 400°C. Fast currents and hot temperatures can quickly overwhelm communities living in the shadow of volcanoes, such as what happened to Pompeii and Herculaneum after the 79 C.E. eruption of Italy's Mount Vesuvius or to Saint-Pierre after Martinique's Mount Pelée erupted in 1902.

Monte Carlo Analysis of Energy Deposition in Solid State Materials by 400 and 200 MEV Electrons

DTIC Science & Technology

1992-06-01

acca ~pel2=ruvzW ucopty= 125-WOZ.13,S3ZO.25,0.141 roi3.im = (1.1 u.04,3.2e-04,8.5s-04,2.Os-03,2.5u-031 acce ~peiS = roi W accopt0= L4.Ou-04,2.9s...Ewpoipts) p’bftwmat=’(Emtw Ons NOgt dW Wb i ma b 8 114 P"U bpp rull.z= [10.35,10.40,20.90,31.60,42.30,53.10J Fill .aM = [8.72,48.02.56.74,95.46,74.l

In vivo quantification of motion in liver parenchyma and its application in shistosomiasis tissue characterization

NASA Astrophysics Data System (ADS)

Badawi, Ahmed M.; Hashem, Ahmed M.; Youssef, Abou-Bakr M.; Abdel-Wahab, Mohamed F.

1995-03-01

Schistosomiasis is a major problem in Egypt, despite an active control program it is estimated to exist in about 1/3 of the population. Deposition of less functioning fibrous tissues in the liver is the major contributory factor to the hepatic pathology. Fibrous tissues consist of a complex array of connective matrix material and a variety of collagen isotopes. As a result of an increased stromal density (collagen content), the parenchyma became more ectogenic and less elastic (hard). In this study we investigated the effect of cardiac mechanical impulses from the heart and aorta on the kinetics of the liver parenchyma. Under conditions of controlled patient movements and suspended respiration, a 30 frame per second of 588 X 512 ultrasound images (cineloop, 32 pels per cm) are captured from an aTL ultrasound machine then digitized. The image acquisition is triggered by the R wave of the ECG of the patient. The motion that has a forced oscillation form in the liver parenchyma is quantified by tracking of small box (20 - 30 pels) in 16 directions for all the successive 30 frames. The tracking was done using block matching techniques (the max correlation between boxes in time, frequency domains, and the minimum SAD (sum absolute difference) between boxes). The motion is quantified for many regions at different positions within the liver parenchyma for 80 cases of variable degrees of schisto., cirrhotic livers, and for normal livers. The velocity of the tissue is calculated from the displacement (quantified motion), time between frames, and the scan time for the ultrasound scanner. We found that the motion in liver parenchyma is small in the order of very few millimeters, and the attenuation of the mechanical wave for one ECG cycle is higher in the schisto. and cirrhotic livers than in the normal ones. Finally quantification of motion in liver parenchyma due to cardiac impulses under controlled limb movement and respiration may be of value in the characterization of schisto. (elasticity based not scattering based). This value could be used together with the wide varieties of quantitative tissue characterization parameters for pathology differentiation and for differentiating subclasses of cirrhosis as well as the determination of the extent of bilharzial affection.

Sediment deposition and selected water-quality characteristics in Cedar Lake and Lake Olathe, Northeast Kansas, 2000

USGS Publications Warehouse

Mau, D.P.

2002-01-01

The Lake Olathe watershed, located in northeast Kansas, was investigated using bathymetric survey data and reservoir bottom-sediment cores to determine sediment deposition, water-quality trends, and transport of nutrients (phosphorus and nitrogen species), selected trace elements, selected pesticides, and diatoms as indicators of eutrophic (organic-enriched and depleted oxygen supply) conditions. To determine sediment deposition and loads, bathymetric data from Cedar Lake and Lake Olathe, both located in the Lake Olathe watershed, were collected in 2000 and compared to historical topographic data collected when the lakes were built. Approximately 338 acre-feet of sediment deposition has occurred in Cedar Lake since dam closure in 1938, and 317 acre-feet has occurred at Lake Olathe since 1956. Mean annual sediment deposition was 5.45 acre-feet per year (0.89 acre-feet per year per square mile) for Cedar Lake and 7.0 acre-feet per year (0.42 acre-feet per year per square mile) for Lake Olathe. Mean annual sediment loads for the two reservoirs were 9.6 million pounds per year for Cedar Lake and 12.6 million pounds per year for Lake Olathe. Mean concentrations of total phosphorus in bottom-sediment samples from Cedar Lake ranged from 1,370 to 1,810 milligrams per kilogram, and concentrations in bottom-sediment samples from Lake Olathe ranged from 588 to 1,030 milligrams per kilogram. The implication of large total phosphorus concentrations in the bottom sediment of Cedar Lake is that inflow into Cedar Lake is rich in phosphorus and that adverse water-quality conditions could affect water quality in downstream Lake Olathe through discharge of water from Cedar Lake to Lake Olathe via Cedar Creek. Mean annual phosphorus loads transported from the Lake Olathe watershed were estimated to be 14,700 pounds per year for Cedar Lake and 9,720 pounds per year for Lake Olathe. The mean annual phosphorus yields were estimated to be 3.74 pounds per acre per year for Cedar Lake and 0.91 pound per acre per year for Lake Olathe. Phosphorus yields in the Cedar Lake watershed were largest of the six Kansas impoundment watersheds recently studied. Concentrations of total ammonia plus organic nitrogen as nitrogen in bottom sediment increased from upstream to downstream in both Cedar Lake and Lake Olathe. Mean concentrations of total ammonia plus organic nitrogen as nitrogen (N) ranged from 2,000 to 2,700 milligrams per kilogram in bottom-sediment samples from Cedar Lake and from 1,300 to 2,700 milligrams per kilogram in samples from Lake Olathe. There was no statistical significance between total ammonia plus organic nitrogen as nitrogen and depth of bottom sediment. Concentrations of six trace elements in bottom sediment from Cedar Lake and Lake Olathe (arsenic, chromium, copper, lead, nickel, and zinc) exceeded the U.S. Environmental Protection Agency Threshold Effects Levels (TELs) sediment-quality guidelines for aquatic organisms in sediment except for one lead concentration. Probable Effects Levels (PELs) for trace elements, however, were not exceeded at either lake. Organochlorine and organophosphate insecticides were not detected in bottom-sediment samples from either Cedar Lake or Lake Olathe, but the acetanilide herbicides alachlor and metolachlor were detected in sediment from both lakes. The U.S. Environmental Protection Agency has not proposed TEL or PEL guideline concentrations for bottom sediment for any of the organophosphate, acetanilide, or triazine pesticides. The diatoms (microscopic, single-celled organisms) Cyclotella bodanica, an indicator of low organic-enriched water, and Cyclotella meneghiniana, an indicator of organic-enriched water, were both present in bottom sediment from Lake Olathe. The presence of both of these diatoms suggests varying periods of low and high eutrophication in Lake Olathe from 1956 to 2000. The concentrations of two species in bottom sediment from Cedar Lake, Aulacoseira cf alpigena and Cyclotella meneg

Environmental impact of the largest petroleum terminal in SE Brazil: A multiproxy analysis based on sediment geochemistry and living benthic foraminifera

PubMed Central

Duleba, Wânia; Teodoro, Andreia C.; Debenay, Jean-Pierre; Gubitoso, Silas; Pregnolato, Leonardo Antônio; Lerena, Laura Misailidis; Prada, Silvio Miranda; Bevilacqua, José Eduardo

2018-01-01

The Dutos e Terminais do Centro Sul (DTCS) is one of the largest petroleum terminals of the South America located in the São Sebastião Channel (SSC) on the southeastern Brazilian coast. The aims of this study were to compare the sediment quality near the DTCS with that of several sites in the SSC region including the Araçá (AR) domestic sewage outfall and to assess the efficiency of the DTCS wastewater treatment plant. To achieve these goals, textural, geochemical, and living benthic foraminifera results were analyzed for the DTCS, AR, and SSC regions. Sediments in the DTCS area were silty with high concentrations of total organic carbon (1.7–2.4%), total nitrogen (0.2–0.3%), total sulfur (0.4–0.6%), and total (0.12–0.18%) and inorganic phosphorous (0.07–0.11%). These values were higher than those in sediments collected in the SSC and Araçá regions. The sediments’ concentrations of As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn in the SSC and AR regions were lower than their corresponding probable effect levels (PELs). However, sediments near the DTCS were enriched with As, Cu, and Ni, whose concentrations exceeded their corresponding threshold effect levels (TELs). Around the DTCS outfall diffusers, living foraminiferal densities and diversities were lower than those for the other areas studied. In the DTCS area, it was necessary to search 50 to 190 cm3 of sediment to find 100 live specimens. In the SSC and Araçá areas, a maximum of 40 cm3 of sediment was enough to locate 100 live specimens. The lower density and diversity of living foraminifera around the DTCS than around the other areas illustrates the impact of the environmental stress caused by the presence of pollutants. These results indicate that the wastewater treatment plant efficiency is low and its discharge of pollutants from petrochemical waste liquids affects the benthic fauna around the DTCS in a potentially harmful manner. PMID:29432425

Increasing the Chances of Implementing NGSS by Bolstering High School Teacher Knowledge and Views about Climate Change, a NICE NASA Example

NASA Astrophysics Data System (ADS)

Bleicher, R. E.

2013-12-01

Purpose of Presentation This paper will highlight how the results of this initial study foreshadow possibilities of NGSS (NGSS, 2013) playing out in high school classrooms in the near future. Research findings from a three-year NASA-funded project, Promoting Educational Leadership in Climate Science (PEL) will be presented. Objectives and Research Questions PEL aims to increase climate science literacy in high school teachers and students through scientific argumentation using authentic NASA data. This initial study focuses on the following questions: 1. Are teachers increasing their climate science knowledge? 2. Are there changes in teachers' views about climate change? 3. What resources and are provided to assist teachers to develop their students' scientific argumentation skills? Theoretical Framework Because of the changing nature of climate science knowledge and its relevance to societal issues, teachers must be able to understand the basic concepts and remain up-to-date on scientific issues. The need for a more thorough understanding of the concepts of climate change are highlighted by recent studies on the public perceptions and attitudes on the subject (Leiserowitz et al., 2013). Teachers need to understand the difference between skepticism as a characteristic of the nature of science and denial of climate change (Sommervillle & Hasol, 2011). Teachers need to understand the natural and human-induced factors affecting climate, and the potential consequences, and ways to mitigate and adapt to climate change. Generally, when teachers learn about a subject, they demonstrate more self-efficacy to teach about it (Bleicher & Lindgren, 2005). Analytic Strategy Data were analyzed using paired-samples t-tests, independent t -tests, and ANOVA. Latent class analysis was employed to analyze the Six America's Survey data. Correlational studies were conducted to examine possible relationships among variables. Findings in Brief Teachers' content knowledge increased significantly and teachers were more concerned about climate change after participation in PEL. Teachers with higher self-efficacy demonstrated higher climate change science knowledge. Teachers indicated that they felt more confident and were motivated to implement classroom lessons with their students that employed resources rich in NASA climate data and focused on scientific argumentation. References Bleicher, R.E., & Lindgren, J. (2005). Success in learning science and preservice science teaching self-efficacy. Journal of Science Teacher Education. 16, 205-225. Leiserowitz, A., Maibach, E., Roser-Renouf, C., Feinberg, G., & Howe, P.(2013) Climate change in the American mind: Americans' global warming beliefs and attitudes in April, 2013 Yale University and George Mason University. New Haven, CT: Yale Project on Climate Change Communication. Retrieved 7/26/13 from: http://climatechangecommunication.org/sites/default/files/reports/Climate-Beliefs-April-2013.pdf Next Generation Science Standards (NGSS). (2013). Available at http://www.nextgenscience.org/print/121. Somerville, R. C. J. & Hassol, S. J. (2011). Communicating the science of climate change. Physics Today, 64(10), 48-53.

Two types of hadrons

NASA Astrophysics Data System (ADS)

Jaffe, R. L.

2008-05-01

Resonances and enhancements in meson-meson scattering can be divided into two classes distinguished by their behavior as the number of colors (Nc) in QCD becomes large: The first are ordinary mesons that become stable as Nc → ∞. This class includes textbook qbar q mesons as well as glueballs and hybrids. The second class, extraordinary mesons, are enhancements that disappear as Nc → ∞; they subside into the hadronic continuum. This class includes indistinct and controversial objects that have been classified as qbarqbar qq mesons or meson-meson molecules. Peláez's study of the Nc dependence of unitarized chiral dynamics illustrates both classes: the p-wave ππ and Kπ resonances, the ρ (770) and K∗ (892), behave as ordinary mesons; the s-wave ππ and Kπ enhancements, the σ (600) and κ (800), behave like extraordinary mesons. Ordinary mesons resemble Feshbach resonances while extraordinary mesons look more like effects due to potentials in meson-meson scattering channels. I build and explore toy models along these lines. Finally I discuss some related dynamical issues affecting the interpretation of extraordinary mesons.

Biogenic tellurium nanorods as a novel antivirulence agent inhibiting pyoverdine production in Pseudomonas aeruginosa.

PubMed

Mohanty, Anee; Kathawala, Mustafa Hussain; Zhang, Jianhua; Chen, Wei Ning; Loo, Joachim Say Chye; Kjelleberg, Staffan; Yang, Liang; Cao, Bin

2014-05-01

While antibiotic resistance in bacteria is rapidly increasing, the development of new antibiotics has decreased in recent years. Antivirulence drugs disarming rather than killing pathogens have been proposed to alleviate the problem of resistance inherent to existing biocidal antibiotics. Here, we report a nontoxic biogenic nanomaterial as a novel antivirulence agent to combat bacterial infections caused by Pseudomonas aeruginosa. We synthesized, in an environmentally benign fashion, tellurium nanorods (TeNRs) using the metal-reducing bacterium Shewanella oneidensis, and found that the biogenic TeNRs could effectively inhibit the production of pyoverdine, one of the most important virulence factors in P. aeruginosa. Our results suggest that amyloids and extracellular polysaccharides Pel and Psl are not involved in the interactions between P. aeruginosa and the biogenic TeNRs, while flagellar movement plays an important role in the cell-TeNRs interaction. We further showed that the TeNRs (up to 100 µg/mL) did not exhibit cytotoxicity to human bronchial epithelial cells and murine macrophages. Thus, biogenic TeNRs hold promise as a novel antivirulence agent against P. aeruginosa. © 2013 Wiley Periodicals, Inc.

Influence of urban runoff, inappropriate waste disposal practices and World War II on the heavy metal status of sediments in the southern half of Saipan Lagoon, Saipan, CNMI.

PubMed

Denton, Gary R W; Emborski, Carmen A; Habana, Nathan C; Starmer, John A

2014-04-15

Heavy metals were examined in sediments from the southern half of Saipan Lagoon. These waters provided tactical access for US troops during WWII and were heavily shelled at the time. Mercury profiles in sediments were, to some extent, reflective of this event. Samples from the southern end of the lagoon, where an old post-war dumpsite once existed, were found to be substantially enriched with Pb, Cu and Zn. Further north, the lagoon was primarily impacted by urban runoff. Metal enrichment in sediments from this region was generally highest at storm drain outlets and attenuated seawards. Moderate enrichment was rarely exceeded for any element other than Hg beyond the 50 m mark. Sediment quality guidelines used to flag potentially adverse ecological health effects revealed no PEL exceedances. TEL exceedances for Pb and Cu were identified in sediments near the former dumpsite. The public health implications of the data are briefly addressed. Copyright © 2014 Elsevier Ltd. All rights reserved.

Patrol Officer Daily Noise Exposure.

PubMed

Gilbertson, Lynn R; Vosburgh, Donna J H

2015-01-01

Previous research shows that police officers are at a higher risk for noise induced hearing loss (NIHL). Little data exists on the occupational tasks, outside of the firing range, that might lead to the increased risk of NIHL. The current study collected noise dosimetry from patrol officers in a smaller department and a larger department in southern Wisconsin, United States. The noise dosimeters simultaneously measured noise in three virtual dosimeters that had different thresholds, criterion levels, and exchange rates. The virtual dosimeters were set to: the Occupational Safety and Health Administration (OSHA) hearing conservation criteria (OSHA-HC), the OSHA permissible exposure level criteria (OSHA-PEL), and the American Conference of Governmental Industrial Hygienists (ACGIH). In addition to wearing a noise dosimeter during their respective work days, officers completed a log form documenting the type of task performed, the duration of that task, if the task involved the use of a siren, and officer characteristics that may have influenced their noise exposure, such as the type of dispatch radio unit worn. Analysis revealed that the normalized 8-hour time weighted averages (TWA) for all officers fell below the recommended OSHA and ACGIH exposure limits. The tasks involving the use of the siren had significantly higher levels than the tasks without (p = 0.005). The highest noise exposure levels were encountered when patrol officers were assisting other public safety agencies such as a fire department or emergency medical services (79 dBA). Canine officers had higher normalized 8-hr TWA noise exposure than regular patrol officers (p = 0.002). Officers with an evening work schedule had significantly higher noise exposure than the officers with a day or night work schedule (p = 0.023). There were no significant differences in exposure levels between the two departments (p = 0.22). Results suggest that this study population is unlikely to experience NIHL as established by the OSHA or ACGIH occupational exposure levels from the daily occupational tasks that were monitored.

Exploring Hawaiian volcanism

USGS Publications Warehouse

Poland, Michael P.; Okubo, Paul G.; Hon, Ken

2013-01-01

In 1912 the Hawaiian Volcano Observatory (HVO) was established by Massachusetts Institute of Technology professor Thomas A. Jaggar Jr. on the island of Hawaii. Driven by the devastation he observed while investigating the volcanic disasters of 1902 at Montagne Pelée in the Caribbean, Jaggar conducted a worldwide search and decided that Hawai‘i provided an excellent natural laboratory for systematic study of earthquake and volcano processes toward better understanding of seismic and volcanic hazards. In the 100 years since HVO’s founding, surveillance and investigation of Hawaiian volcanoes have spurred advances in volcano and seismic monitoring techniques, extended scientists’ understanding of eruptive activity and processes, and contributed to development of global theories about hot spots and mantle plumes.

Exploring Hawaiian Volcanism

NASA Astrophysics Data System (ADS)

Poland, Michael P.; Okubo, Paul G.; Hon, Ken

2013-02-01

In 1912 the Hawaiian Volcano Observatory (HVO) was established by Massachusetts Institute of Technology professor Thomas A. Jaggar Jr. on the island of Hawaii. Driven by the devastation he observed while investigating the volcanic disasters of 1902 at Montagne Pelée in the Caribbean, Jaggar conducted a worldwide search and decided that Hawai`i provided an excellent natural laboratory for systematic study of earthquake and volcano processes toward better understanding of seismic and volcanic hazards. In the 100 years since HVO's founding, surveillance and investigation of Hawaiian volcanoes have spurred advances in volcano and seismic monitoring techniques, extended scientists' understanding of eruptive activity and processes, and contributed to development of global theories about hot spots and mantle plumes.

Resuspension of sediment, a new approach for remediation of contaminated sediment.

PubMed

Pourabadehei, Mehdi; Mulligan, Catherine N

2016-06-01

Natural events and anthropogenic activities are the reasons of undesirable resuspension of contaminated sediments in aquatic environment. Uncontrolled resuspension could remobilize weakly bound heavy metals into overlying water and pose a potential risk to aquatic ecosystem. Shallow harbours, with contaminated sediments are subjected to the risk of uncontrolled resuspension. Remediation of sediments in these areas cannot be performed by conventional in situ methods (e.g. capping with or without reactive amendment). Ex situ remediation also requires dredging of sediment, which could increase the risk of spreading contaminants. Alternatively, the resuspension technique was introduced to address these issues. The concept of the resuspension method is that finer sediments have a greater tendency to adsorb the contamination. Therefore, finer sediments, believed carry more concentration of contaminants, were targeted for removal from aquatic environment by a suspension mechanism in a confined water column. The objective of this study was to evaluate the feasibility of the resuspension technique as a new approach for remediation of contaminated sediment and a viable option to reduce the risk of remobilization of contaminants in harbours due to an undesirable resuspension event. Unlike the common in situ techniques, the resuspension method could successfully reduce the total concentration of contaminants in almost all samples below the probable effect level (PEL) with no significant change in the quality of overlying water. The results indicated that removal efficiency could be drastically enhanced for metals in sediment with a higher enrichment factor. Moreover, availability of metals (e.g. Cd and Pb) with a high concentration in labile fractions was higher in finer sediments with a high enrichment factor. Consequently, removal of contaminants from sediment through the resuspension method could reduce the risk of mobility and availability of metals under changing environmental conditions. Potential dredging in harbours could be performed safer and more cost-effective afterward. Copyright © 2016 Elsevier Ltd. All rights reserved.

Inhibitory effects of anthocyanins on secretion of Helicobacter pylori CagA and VacA toxins.

PubMed

Kim, Sa-Hyun; Park, Min; Woo, Hyunjun; Tharmalingam, Nagendran; Lee, Gyusang; Rhee, Ki-Jong; Eom, Yong Bin; Han, Sang Ik; Seo, Woo Duck; Kim, Jong Bae

2012-01-01

Anthocyanins have been studied as potential antimicrobial agents against Helicobacter pylori. We investigated whether the biosynthesis and secretion of cytotoxin-associated protein A (CagA) and vacuolating cytotoxin A (VacA) could be suppressed by anthocyanin treatment in vitro. H. pylori reference strain 60190 (CagA(+)/VacA(+)) was used in this study to investigate the inhibitory effects of anthocyanins; cyanidin 3-O-glucoside (C3G), peonidin 3-O-glucoside (Peo3G), pelargonidin 3-O-glucoside (Pel3G), and malvidin 3-O-glucoside (M3G) on expression and secretion of H. pylori toxins. Anthocyanins were added to bacterial cultures and Western blotting was used to determine secretion of CagA and VacA. Among them, we found that C3G inhibited secretion of CagA and VacA resulting in intracellular accumulation of CagA and VacA. C3G had no effect on cagA and vacA expression but suppressed secA transcription. As SecA is involved in translocation of bacterial proteins, the down-regulation of secA expression by C3G offers a mechanistic explanation for the inhibition of toxin secretion. To our knowledge, this is the first report suggesting that C3G inhibits secretion of the H. pylori toxins CagA and VacA via suppression of secA transcription.

Inhibitory Effects of Anthocyanins on Secretion of Helicobacter pylori CagA and VacA Toxins

PubMed Central

Kim, Sa-Hyun; Park, Min; Woo, Hyunjun; Tharmalingam, Nagendran; Lee, Gyusang; Rhee, Ki-Jong; Eom, Yong Bin; Han, Sang Ik; Seo, Woo Duck; Kim, Jong Bae

2012-01-01

Anthocyanins have been studied as potential antimicrobial agents against Helicobacter pylori. We investigated whether the biosynthesis and secretion of cytotoxin-associated protein A (CagA) and vacuolating cytotoxin A (VacA) could be suppressed by anthocyanin treatment in vitro. H. pylori reference strain 60190 (CagA+/VacA+) was used in this study to investigate the inhibitory effects of anthocyanins; cyanidin 3-O-glucoside (C3G), peonidin 3-O-glucoside (Peo3G), pelargonidin 3-O-glucoside (Pel3G), and malvidin 3-O-glucoside (M3G) on expression and secretion of H. pylori toxins. Anthocyanins were added to bacterial cultures and Western blotting was used to determine secretion of CagA and VacA. Among them, we found that C3G inhibited secretion of CagA and VacA resulting in intracellular accumulation of CagA and VacA. C3G had no effect on cagA and vacA expression but suppressed secA transcription. As SecA is involved in translocation of bacterial proteins, the down-regulation of secA expression by C3G offers a mechanistic explanation for the inhibition of toxin secretion. To our knowledge, this is the first report suggesting that C3G inhibits secretion of the H. pylori toxins CagA and VacA via suppression of secA transcription. PMID:23155357

Assessment and evaluation of noise controls on roof bolting equipment and a method for predicting sound pressure levels in underground coal mining

NASA Astrophysics Data System (ADS)

Matetic, Rudy J.

Over-exposure to noise remains a widespread and serious health hazard in the U.S. mining industries despite 25 years of regulation. Every day, 80% of the nation's miners go to work in an environment where the time weighted average (TWA) noise level exceeds 85 dBA and more than 25% of the miners are exposed to a TWA noise level that exceeds 90 dBA, the permissible exposure limit (PEL). Additionally, MSHA coal noise sample data collected from 2000 to 2002 show that 65% of the equipment whose operators exceeded 100% noise dosage comprise only seven different types of machines; auger miners, bulldozers, continuous miners, front end loaders, roof bolters, shuttle cars (electric), and trucks. In addition, the MSHA data indicate that the roof bolter is third among all the equipment and second among equipment in underground coal whose operators exceed 100% dosage. A research program was implemented to: (1) determine, characterize and to measure sound power levels radiated by a roof bolting machine during differing drilling configurations (thrust, rotational speed, penetration rate, etc.) and utilizing differing types of drilling methods in high compressive strength rock media (>20,000 psi). The research approach characterized the sound power level results from laboratory testing and provided the mining industry with empirical data relative to utilizing differing noise control technologies (drilling configurations and types of drilling methods) in reducing sound power level emissions on a roof bolting machine; (2) distinguish and correlate the empirical data into one, statistically valid, equation, in which, provided the mining industry with a tool to predict overall sound power levels of a roof bolting machine given any type of drilling configuration and drilling method utilized in industry; (3) provided the mining industry with several approaches to predict or determine sound pressure levels in an underground coal mine utilizing laboratory test results from a roof bolting machine and (4) described a method for determining an operators' noise dosage of a roof bolting machine utilizing predicted or determined sound pressure levels.

Simulating thermal stress features on hot planetary surfaces in vacuum at high temperature facility in the PEL laboratory

NASA Astrophysics Data System (ADS)

Maturilli, A.; Ferrari, S.; Helbert, J.; D'Incecco, P.; D'Amore, M.

2011-12-01

In the Planetary Emissivity Laboratory (PEL) at the Institute for Planetary Research of the German Aerospace Center (DLR) in Berlin, we set-up a simulation chamber for the spectroscopic investigation of minerals separates under Mercurial conditions. The chamber can be evacuated to 10-4 bar and the target samples heated to 700 K within few minutes, thanks to the innovative inductive heating system. While developing the protocol for the high temperature spectroscopy measurements we discovered interesting "morphologies" on the sample surfaces. The powders are poured into stainless steel cups of 50 mm internal diameter, 8 mm height and 3 mm depth, having a 5 mm thick base (thus leaving 3 mm free space for the minerals), and rim 1 mm thick. We selected several minerals of interest for Mercurial surface composition and for each of them we analyzed various grain size separates, to study the influence of grain dimensions to the process of thermal stressing. We observed that for the smaller grain size separate (0-25 μm) the thermal stress mainly induces large depressions and fractures, while on larger grain sizes (125-250 μm) small depressions and a cratered surface. Our current working hypothesis is that these features are mainly caused by thermal stress induced by a radiatively quickly cooling surface layer covering the much hotter bulk material. Further investigation is ongoing to understand the processes better. The observed morphologies exhibit surprising similarities to features observed at planetary scale size for example on Mercury and even on Venus. Especially the high resolution images provided currently from MESSENGER'S Mercury Dual Imaging System (MDIS) instrument has revealed plains dominated by polygonal fractures whose origin still have to be determined. Our laboratory analogue studies might in the future provide some insight into the processes creating those features

Development of models and software for liquidus temperatures of glasses of HWVP products. Final report

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

Hrma, P.R.; Vienna, J.D.; Pelton, A.D.

In an earlier report [92 Pel] was described the development of software and thermodynamic databases for the calculation of liquidus temperatures of glasses of HWVP products containing the components SiO{sub 2}-B{sub 2}O{sub 3}-Na{sub 2}O-Li{sub 2}O-CaO-MgO-Fe{sub 2}O{sub 3}-Al{sub 2}O{sub 3}-ZrO{sub 2}-{open_quotes}others{close_quotes}. The software package developed at that time consisted of the EQUILIB program of the F*A*C*T computer system with special input/output routines. Since then, Battelle has purchased the entire F*A*C*T computer system, and this fully replaces the earlier package. Furthermore, with the entire F*A*C*T system, additional calculations can be performed such as calculations at fixed O{sub 2}, SO{sub 2} etc. pressures,more » or graphing of output. Furthermore, the public F*A*C*T database of over 5000 gaseous species and condensed phases is now accessible. The private databases for the glass and crystalline phases were developed for Battelle by optimization of thermodynamic and phase diagram data. That is, all available data for 2- and 3-component sub-systems of the 9-component oxide system were collected, and parameters of model equations for the thermodynamic properties were found which best reproduce all the data. For representing the thermodynamic properties of the glass as a function of composition and temperature, the modified quasichemical model was used. This model was described in the earlier report [92 Pel] along with all the optimizations. With the model, it was possible to predict the thermodynamic properties of the 9-component glass, and thereby to calculate liquidus temperatures. Liquidus temperatures measured by Battelle for 123 CVS glass compositions were used to test the model and to refine the model by the addition of further parameters.« less

Engineering of a highly efficient Xe₂*-excilamp (xenon excimer lamp, λmax=172 nm, η=40%) and qualitative comparison to a low-pressure mercury lamp (LP-Hg, λ=185/254 nm) for water purification.

PubMed

Al-Gharabli, Samer; Engeßer, Patrick; Gera, Diana; Klein, Sandra; Oppenländer, Thomas

2016-02-01

Excilamps are mercury-free gas-discharge sources of non-coherent VUV or UV radiation with high radiant power and a long lifetime. The most efficient excilamp that is currently available on the market is a VUV xenon excilamp system (Xe2(*)-excimer lamp, λ(max) = 172 nm) with a stated radiant efficiency η of 40% at an electrical input power P(el) of 20 W, 50 W or 100 W. In this paper, the use of this highly efficient Xe2(*)-excilamp (P(el) = 20 W) for water treatment is demonstrated using a recirculating laboratory photoreactor system with negative radiation geometry. The efficiency in the 172 nm initiated bleaching of aqueous solutions of Rhodamine B is compared to that initiated by a common low-pressure mercury (LP-Hg) lamp (185 nm, TNN 15/32). The dependence of the pseudo zero order rate constant k´ of decolorization of RhB on the flow rate and on the initial concentration of RhB was investigated. Both lamps exhibited dependences of k´ on the initial concentration of RhB, which represents a typical saturation kinetical behavior. The saturation kinetics was very prominent in the case of the Xe2(*)-excilamp. Also, the Xe2(*)-excilamp treatment exhibited a significant influence on the flow rate of the RhB aqueous solution, which was not the case during the LP-Hg lamp initiated bleaching of RhB. The results of this paper demonstrate that Xe2(*)-excilamps can be used for VUV-initiated water purification. However, to reach the maximum efficacy of the Xe2(*)-excilamp for photo-initiated water purification further engineering optimization of the photoreactor concept is necessary. Copyright © 2015 Elsevier Ltd. All rights reserved.

Towards a next generation open-source video codec

NASA Astrophysics Data System (ADS)

Bankoski, Jim; Bultje, Ronald S.; Grange, Adrian; Gu, Qunshan; Han, Jingning; Koleszar, John; Mukherjee, Debargha; Wilkins, Paul; Xu, Yaowu

2013-02-01

Google has recently been developing a next generation opensource video codec called VP9, as part of the experimental branch of the libvpx repository included in the WebM project (http://www.webmproject.org/). Starting from the VP8 video codec released by Google in 2010 as the baseline, a number of enhancements and new tools have been added to improve the coding efficiency. This paper provides a technical overview of the current status of this project along with comparisons and other stateoftheart video codecs H. 264/AVC and HEVC. The new tools that have been added so far include: larger prediction block sizes up to 64x64, various forms of compound INTER prediction, more modes for INTRA prediction, ⅛pel motion vectors and 8tap switchable subpel interpolation filters, improved motion reference generation and motion vector coding, improved entropy coding and framelevel entropy adaptation for various symbols, improved loop filtering, incorporation of Asymmetric Discrete Sine Transforms and larger 16x16 and 32x32 DCTs, frame level segmentation to group similar areas together, etc. Other tools and various bitstream features are being actively worked on as well. The VP9 bitstream is expected to be finalized by earlyto mid2013. Results show VP9 to be quite competitive in performance with mainstream stateoftheart codecs.

Genome-wide mapping of the RNA targets of the Pseudomonas aeruginosa riboregulatory protein RsmN.

PubMed

Romero, Manuel; Silistre, Hazel; Lovelock, Laura; Wright, Victoria J; Chan, Kok-Gan; Hong, Kar-Wai; Williams, Paul; Cámara, Miguel; Heeb, Stephan

2018-04-30

Pseudomonads typically carry multiple non-identical alleles of the post-transcriptional regulator rsmA. In Pseudomonas aeruginosa, RsmN is notable in that its structural rearrangement confers distinct and overlapping functions with RsmA. However, little is known about the specificities of RsmN for its target RNAs and overall impact on the biology of this pathogen. We purified and mapped 503 transcripts directly bound by RsmN in P. aeruginosa. About 200 of the mRNAs identified encode proteins of demonstrated function including some determining acute and chronic virulence traits. For example, RsmN reduces biofilm development both directly and indirectly via multiple pathways, involving control of Pel exopolysaccharide biosynthesis and c-di-GMP levels. The RsmN targets identified are also shared with RsmA, although deletion of rsmN generally results in less pronounced phenotypes than those observed for ΔrsmA or ΔrsmArsmNind mutants, probably as a consequence of different binding affinities. Targets newly identified for the Rsm system include the small non-coding RNA CrcZ involved in carbon catabolite repression, for which differential binding of RsmN and RsmA to specific CrcZ regions is demonstrated. The results presented here provide new insights into the intricacy of riboregulatory networks involving multiple but distinct RsmA homologues.

An Integrated Approach to Assess Exposure and Health-Risk from Polycyclic Aromatic Hydrocarbons (PAHs) in a Fastener Manufacturing Industry

PubMed Central

Hsu, Hsin-I; Lin, Ming-Yeng; Chen, Yu-Cheng; Chen, Wang-Yi; Yoon, Chungsik; Chen, Mei-Ru; Tsai, Perng-Jy

2014-01-01

An integrated approach was developed to assess exposure and health-risk from polycyclic aromatic hydrocarbons (PAHs) contained in oil mists in a fastener manufacturing industry. One previously developed model and one new model were adopted for predicting oil mist exposure concentrations emitted from metal work fluid (MWF) and PAHs contained in MWF by using the fastener production rate (Pr) and cumulative fastener production rate (CPr) as predictors, respectively. By applying the annual Pr and CPr records to the above two models, long-term workplace PAH exposure concentrations were predicted. In addition, true exposure data was also collected from the field. The predicted and measured concentrations respectively served as the prior and likelihood distributions in the Bayesian decision analysis (BDA), and the resultant posterior distributions were used to determine the long-term exposure and health-risks posed on workers. Results show that long term exposures to PAHs would result in a 3.1%, 96.7%, and 73.4% chance of exceeding the PEL-TWA (0.2 mg/m3), action level (0.1 mg/m3), and acceptable health risk (10−3), respectively. In conclusion, preventive measures should be taken immediately to reduce workers’ PAH exposures. PMID:25226413

Lead exposure and blood pressure among workers in diverse industrial plants in Kenya.

PubMed

Were, Faridah H; Moturi, M Charles; Gottesfeld, P; Wafula, Godfrey A; Kamau, Geoffrey N; Shiundu, Paul M

2014-01-01

The study evaluated airborne exposures and blood lead (BPb) levels in 233 production workers at six diverse industrial plants in Kenya. Blood and personal breathing zone air samples were collected and analyzed for lead (Pb) using atomic absorption spectroscopy. Blood pressure (BP) levels were measured using a standard mercury sphygmomanometer. The results indicated mean airborne Pb levels ± standard deviation (SD) as follows: 183.2 ± 53.6 μg/m(3) in battery recycling, 133.5 ± 39.6 μg/m(3) in battery manufacturing, 126.2 ± 39.9 μg/m(3) in scrap metal welding, 76.3 ± 33.2 μg/m(3) in paint manufacturing, 27.3 ± 12.1 μg/m(3) in a leather manufacturing, and 5.5 ± 3.6 μg/m(3) in a pharmaceutical plant. The mean airborne Pb levels exceeded the U.S. Occupational Safety and Health Administration (OSHA) 8-hr time-weighted average (TWA) permissible exposure limit (PEL) for Pb of 50 μg/m(3) in the battery manufacturing, battery recycling, welding, and paint manufacturing plants. Similarly, mean BPb concentrations exceeded the American Conference of Governmental Industrial Hygienists (ACGIH®) biological exposure index (BEI) for Pb of 30 μg/dl. A significant positive association was observed between BPb and breathing zone air Pb (R(2) = 0.73, P < 0.001). Approximately 30% of the production workers (N = 233) were in the hypertensive range with an average systolic and diastolic blood pressure (BP) of 134.7 ± 12.7 mmHg and 86.4 ± 8.9 mmHg, respectively. In the multivariate regression analysis, age, duration of work, airborne Pb and BPb levels were significantly associated (P < 0.05) with a change in BP. We recommend improved engineering controls, work practices, and personal hygiene to reduce Pb exposures. In addition, workers should undergo comprehensive medical surveillance to include BPb and BP testing, and airborne Pb assessments in all industries with significant lead exposures.

A Research Design for NASA-Funded Professional Development Projects

NASA Astrophysics Data System (ADS)

Bleicher, R. E.; Lambert, J.; Getty, S. R.

2011-12-01

This proposal outlines a research plan designed to measure gains in student learning resulting from their teachers participating in professional development. Project Description Misconceptions about global climate change (GCC) are prevalent in the general public (Kellstedt, Zahran, & Vedlitz, 2008; Washington & Cook, 2011). One solution is to provide high school students with a better grounding in the basic science and data that underlie GCC. The overarching goal of a NASA-funded project, Promoting Educational Leadership in Climate Change Literacy (PEL), is to increase GCC literacy in high school students. Research Design The research design is interpretative (Erickson, 2006), framed within a multi-method design, synthesizing both quantitative and qualitative data sources (Morse, 2003). Overall, the data will provide rich information about the PEL's impact on curriculum development, teacher pedagogical knowledge, and student learning. The expectancy-value theory of achievement motivation (E-V-C) (Fan, 2011; Wigfield & Eccles, 1994) provides a theoretical foundation for the research. Expectancy is the degree to which a teacher or student has reason to expect that they will be successful in school. Value indicates whether they think that performance at school will be worthwhile to them. Cost is the perceived sacrifices that must be undertaken, or factors that can inhibit, a successful performance at school. For students, data from an embedded E-V-C investigation will help articulate how E-V-C factors relate to student interest in science, continuing to study science, or embarking on STEM related careers. For teachers, the E-V-C measures will give insight into a key mediating variable on student achievement in science. The evaluation will seek to address research questions at the student and teacher levels. Table 1 presents a sample of research questions and data sources. This is a sample of a much larger set of questions that will be addressed in the project. Data Analysis Data will be analyzed using a strategy developed by Huberman and Miles (2002). This methodology provides a framework for researchers to perform three research functions: 1) reduce the data to a subset of information (categories) without losing essential data, 2) display (matrices, maps, summaries) this information in a manner that facilitates group discussion and notation of consensus upon emerging patterns, and 3) draw and verify conclusions. The multiple sources of qualitative and quantitative data allow for triangulation of findings, which helps establish a measure of validity and reliability to final findings and recommendations for future research and changes to the project.
Table 1. Research Questions, Data Sources.

Planar electroluminescent panel techniques

NASA Technical Reports Server (NTRS)

Kerr, C.; Kell, R. E.

1973-01-01

Investigations of planar electroluminescent multipurpose displays with latch-in memory are described. An 18 x 24 in. flat, thin address panel with elements spacing of 0.100 in. was constructed which demonstrated essentially uniform luminosity of 3-5 foot lamberts for each of its 43200 EL cells. A working model of a 4-bit EL-PC (electroluminescent photoconductive) electrooptical decoder was made which demonstrated the feasibility of this concept. A single-diagram electroluminescent display device with photoconductive-electroluminescent latch-in memory was constructed which demonstrated the conceptual soundness of this principle. Attempts to combine these principles in a single PEL multipurpose display with latch-in memory were unsuccessful and were judged to exceed the state-of-the-art for close-packed (0.10 in. centers) photoconductor-electroluminescent cell assembly.

AWS (Air Weather Service) Climatic Briefs: Asia.

DTIC Science & Technology

1984-12-01

EYR 1 1 11 10 10 151101010 10 10 15 15 15 15 151 15115 15 15 1510 1EXThi24ES INCLUDED FROM GBMO TABLES OF TEKP/RH/PRECIP OF THE WORLD . ~MAXIMUM WID...a 2 10 2 -_._ 1 P_ 4vSBT TA LA E 7 0. 0 2 O . 3 0. R ( A A __1A ____ 1... tha 18&20 0 0 0 # 3 3 2 o_ 1_ 9 -3 miles 2300 0 0 0- 1_ 3 1 0 1 i 1 4 WAR C...Awl S ’~ 6218 . - . . . .. . . .~. . . . . . C3 DATE WAR 72 GO.LE.- P1PAREDIT USAFITAC STATION KAM TAIPl lOP TAIWAN PEl00 JAN S0*,IJL 72 I STMLT6S ICTP

The development and regulation of occupational exposure limits in Taiwan.

PubMed

Shih, Tung-Sheng; Wu, Kuen-Yuh; Chen, Hong-I; Chang, Cheng-Ping; Chang, Ho-Yuan; Huang, Yi-Shiao; Liou, Saou-Hsing

2006-11-01

The occupational exposure limits (OELs) in Taiwan was promulgated in 1974 and has been revised five times since then. Many of the OELs were adopted from the most recent ACGIH TLVs and US OSHA PELs. A total of 483 chemicals were listed in the current Taiwan OELs Standard. The procedures of OELs development in Taiwan include the IOSH organized a recommended exposure limits (RELs) Committee to select the target chemicals and to recommend the RELs through literature review based on the health effects in the first stage, then, the CLA put policy needs, economical and technical feasibility into consideration and set up the final OELs at the second stage. A standard operation manual of RELs Committee has been developed. Based on our experience, several issues including the participation of representatives from a comprehensive spectrum, communication/education and training/enforcement, continuous collection of the local exposure data and health hazard information, use of health risk assessment, consideration of economic, and technical feasibility, as well as the globalization and information and experience sharing are critical in developing the appropriate OELs. Three examples including benzene, crystalline silica, and 2-methoxy ethanol are given to demonstrate the operation of system.

Resurvey of quality of surface water and bottom material of the Barataria Preserve of Jean Lafitte National Historical Park and Preserve, Louisiana, 1999-2000

USGS Publications Warehouse

Swarzenski, Christopher M.

2003-01-01

The quality of water and bottom material in the Barataria Preserve of Jean Lafitte National Historical Park and Preserve, Louisiana, was surveyed from March 1999 to May 2000. Organochlorine, chlorophenoxy acid, and organophosphorus pesticides; polychlorinated biphenyls (PCB?s); and trace elements were analyzed in surface water and bottom material from three sites previously sampled in a 1981-82 survey. Surface water at six sites was sampled and analyzed for selected nutrients and major inorganic ions based on their importance to human health, the health of the marshes of the Barataria Preserve, or their usefulness in tracking the circulation of Mississippi River water in the Barataria Preserve. Southern Louisiana was in a moderate to severe drought during most of the sampling period, which elevated salinity in the Barataria Preserve for at least 8 months. Specific conductance values were less than 3,000 ?S/cm (microsiemens per centimeter at 25 degrees Celsius) in surface water throughout the Barataria Preserve from March through September 1999. Specific conductance values increased over the next 2 months and then remained between 5,000 and 6,000 ?S/cm. The herbicide 2,4-D was detected in water at the two sites sampled in August 1999 but not at any site during the two other sampling times. Iron, manganese, and the trace elements copper, nickel, and zinc were detected in dissolved and whole-water samples at all three sites. Nitrite+ nitrate, as nitrogen, concentrations ranged from less than 0.002 to 0.19 mg/L (milligrams per liter). Ammonia, as nitrogen, concentrations ranged from less than 0.01 to 0.16 mg/L. Orthophosphate, as phosphorus, concentrations ranged from less than 0.002 to 0.14 mg/L. Calcium, magnesium, potassium, sulfate, and chloride concentrations in surface water were elevated due to the marine influence on the composition of surface water in the Barataria Preserve during the sampling period. Sulfate and chloride concentrations reached 379 and 2,830 mg/L, respectively. Polychlorinated biphenyls, chlordane, and DDT were detected in bottom material. Trace elements were detected in bottom material at all three of the sampled sites. Arsenic concentrations ranged from 4 to 9 ?g/g (micrograms per gram) and lead concentrations from 20 to 31 ?g/g. Mercury concentrations also were above laboratory reporting levels (LRL?s) for bottom material at all three sites. The herbicide 2,4-D was detected in surface water during both surveys. Other organic compounds were not detected in surface water. Mercury and chromium were detected in surface water at all three sites during the 1981-82 survey but were below LRL?s during the 1999-2000 survey. Changes in chemical characteristics of bottom material occurred during the years between the 1981-82 and 1999-2000 surveys. DDT decreased in the bottom material at Bayou Segnette near Barataria. DDE, a degradation product, increased at this site, indicating that over time, DDT concentrations are decreasing in bottom material. PCB?s were present in similar concentrations (Bayou Segnette near Barataria) or increased (Bayou Segnette 4.6 miles below Westwego) from 1981-82 to 1999-2000. Cadmium concentrations consistently decreased by half or more at all three sites from 1981-82 to 1999-2000. Mercury concentrations were consistently lower at all three sites in the 1999-2000 survey, but the differences from the 1981-82 survey were small. Chromium concentrations increased at two of the three sites from 1981-82 to the present survey. At the third site, no chromium value was available for the earlier survey. Concentrations of copper and nickel increased in bottom material at the two sites on Bayou Segnette, but decreased at Kenta Canal northwest of Westwego. Probable Effects Levels (PEL?s) and Interim Sediment Quality Guidelines (ISQG?s) concentrations, as tabulated by the Canadian Council of Ministers of the

Assessment of trace metal contamination in stream sediments of the Tuul River, Mongolia

NASA Astrophysics Data System (ADS)

Dalai, B.

2011-12-01

Thirty four sediment samples were collected in Ulaanbaatar basin, along the Tuul River which is the main source of water for the capital city Ulaanbaatar, Mongolia. The catchment can be divided three parts (upper, middle, and lower) according to the extent of urbanization. The upper part of the river basin is comparatively less affected by human activity and it can be represent the natural background condition. The middle part is the urban area of Ulaanbaatar and lower part extends SW of the end of the urban area mostly used for agriculture and farming activity. The present study focused on the levels of potentially toxic metals such as As, Pb, Zn, Cu, Ni and Cr in order to assess the extent of environmental pollution and to discuss the origin of these contaminants in sediments of the Tuul River using X-ray fluorescence analyses. Metal concentrations in the sediments are discussed by comparison with average Upper Continental Crust values (UCC) and ecological risk assessment by reference to sediment quality guidelines (SQG). The results showed thet average abundances of metals are measurable contrast between upper, middle and lower parts of the river. The Upper part and its surrounding area's sediment signature indicated that more depletion comparatively other parts (Pb, Zn, Cu, Ni and Cr), whereas enrichment sign did not detect. However, among the Upper part sediments, two samples (NA1 and NA2) enriched with trace metals which sampled from Nalaikh area were significantly affected by coal mining activity. Most metals are (As, Pb, Zn, Cu and Ni) higher in the middle part (within the city) than the upper and lower part due to the urban activities. The small tributaries such as Selbe, Uliastai, Gachuurt and Tolgoit were significantly affected by urban activities and highest values are detected from them. Lower part significantly enriched with Cr (av 98 ppm). Highest concentration of Cr (183 ppm) was at Shuvuu which is receiving point of domestic and industrial wastewater discharge. However all three parts show depletion in some chalcophile and HFSE elements (Cu, Ni, Cr, Sr, Nb, Zr, Th, Sc). This depletion of elements relative to UCC suggest that the river sediments were derived from a highly felsic crustal source. The assessment of ecological risk assessment result showed that adverse aquatic biological effects caused by As and Cr. While, concentration of Pb, Zn, Cu and Ni are generally below their respective Threshold effect level (TEL), in middle part reaches to reach values bordering on the Probable effect level (PEL). This indicated that anthropogenic contribution in the urban areas, increasing values above a naturally low regional background.

Evidence Report: Risk of Acute and Late Central Nervous System Effects from Radiation Exposure

NASA Technical Reports Server (NTRS)

Nelson, Gregory A.; Simonsen, Lisa; Huff, Janice L.

2016-01-01

Possible acute and late risks to the central nervous system (CNS) from galactic cosmic rays (GCR) and solar particle events (SPE) are concerns for human exploration of space. Acute CNS risks may include: altered cognitive function, reduced motor function, and behavioral changes, all of which may affect performance and human health. Late CNS risks may include neurological disorders such as Alzheimer's disease (AD), dementia and premature aging. Although detrimental CNS changes are observed in humans treated with high-dose radiation (e.g., gamma rays and 9 protons) for cancer and are supported by experimental evidence showing neurocognitive and behavioral effects in animal models, the significance of these results on the morbidity to astronauts has not been elucidated. There is a lack of human epidemiology data on which to base CNS risk estimates; therefore, risk projection based on scaling to human data, as done for cancer risk, is not possible for CNS risks. Research specific to the spaceflight environment using animal and cell models must be compiled to quantify the magnitude of CNS changes in order to estimate this risk and to establish validity of the current permissible exposure limits (PELs). In addition, the impact of radiation exposure in combination with individual sensitivity or other space flight factors, as well as assessment of the need for biological/pharmaceutical countermeasures, will be considered after further definition of CNS risk occurs.

Evidence Report: Risk of Acute and Late Central Nervous System Effects from Radiation Exposure

NASA Technical Reports Server (NTRS)

Nelson, Gregory A.; Simonsen, Lisa; Huff, Janice L.

2015-01-01

Possible acute and late risks to the central nervous system (CNS) from galactic cosmic rays (GCR) and solar particle events (SPE) are a documented concern for human exploration of space. Acute CNS risks include: altered cognitive function, reduced motor function, and behavioral changes, all of which may affect performance and human health. Late CNS risks include neurological disorders such as Alzheimer's disease (AD), dementia and premature aging. Although detrimental CNS changes are observed in humans treated with high-dose radiation (e.g., gamma rays and protons) for cancer and are supported by experimental evidence showing neurocognitive and behavioral effects in animal models, the significance of these results on the morbidity to astronauts has not been elucidated. There is a lack of human epidemiology data on which to base CNS risk estimates; therefore, risk projection based on scaling to human data, as done for cancer risk, is not possible for CNS risks. Research specific to the spaceflight environment using animal and cell models must be compiled to quantify the magnitude of CNS changes in order to estimate this risk and to establish validity of the current permissible exposure limits (PELs). In addition, the impact of radiation exposure in combination with individual sensitivity or other space flight factors, as well as assessment of the need for biological/pharmaceutical countermeasures, will be considered after further definition of CNS risk occurs.

Survey Of Lossless Image Coding Techniques

NASA Astrophysics Data System (ADS)

Melnychuck, Paul W.; Rabbani, Majid

1989-04-01

Many image transmission/storage applications requiring some form of data compression additionally require that the decoded image be an exact replica of the original. Lossless image coding algorithms meet this requirement by generating a decoded image that is numerically identical to the original. Several lossless coding techniques are modifications of well-known lossy schemes, whereas others are new. Traditional Markov-based models and newer arithmetic coding techniques are applied to predictive coding, bit plane processing, and lossy plus residual coding. Generally speaking, the compression ratio offered by these techniques are in the area of 1.6:1 to 3:1 for 8-bit pictorial images. Compression ratios for 12-bit radiological images approach 3:1, as these images have less detailed structure, and hence, their higher pel correlation leads to a greater removal of image redundancy.

Simulation of permeability evolution of leakage pathway in carbonate-rich caprocks in carbon sequestration

NASA Astrophysics Data System (ADS)

Guo, B.; Fitts, J. P.; Dobossy, M. E.; Peters, C. A.

2013-12-01

Geologic carbon sequestration in deep saline aquifers is a promising strategy for mitigating climate change. A major concern is the possibility of brine and CO2 migration through the caprock such as through fractures and faults. In this work, we examine the extent to which mineral dissolution will substantially alter the porosity and permeability of caprock leakage pathways as CO2-acidified brine flows through them. Three models were developed. Firstly, a reactive transport model, Permeability Evolution of Leakage pathway (PEL), was developed to simulate permeability evolution of a leakage pathway during the injection period, and assumes calcite is the only reactive mineral. The system domain is a 100 m long by 0.2 m diameter cylindrical flow path with fixed boundaries containing a rock matrix with an initial porosity of 30% and initial permeability of 1×10-13 m2. One example result is for an initial calcite volume fraction (CVF) of 0.20, in which all the calcite is dissolved after 50 years and the permeability reaches 3.2×10-13 m2. For smaller values of CVF, the permeability reaches its final value earlier but the increase in permeability is minimal. For a large value of CVF such as 0.50, the permeability could eventually reach 1×10-12 m2, but the large amount of dissolved calcium buffers the solution and slows the reaction. After 50 years the permeability change is negligible. Thus, there is a non-monotonic relationship between the amount of calcite in the rock and the resulting permeability change because of the competing dynamics of calcite dissolution and alkalinity build-up. In the second model, PEL was coupled to an existing basin-scale multiphase flow model, Princeton's Estimating Leakage Semi-Analytical (ELSA) model. The new model, ELSA-PEL, estimates the brine and CO2 leakage rates during the injection period under conditions of permeability evolution. The scenario considered in this work is for 50 years of CO2 injection into the Mt. Simon formation in the Michigan basin at an injection rate of 1 Mt/y. As an example, for a CVF value of 5%, the brine leakage rate after fifty years for a leakage pathway 1,000 m distance from the injection well is 0.88 kg/s, which is 2.4% larger than if there were no geochemical evolution of the permeability. In a sensitivity analysis with regard to the distance between the leakage pathway and the injection well, it was found that the cumulative leakage first increases with the distance and the relationship reverses after a certain distance. When the leakage pathway is farther away, the pressure increment drops leading to less acid brine flow; meanwhile, the time before the CO2 plume reaches the pathway is longer and this lengthens the reaction time with brine. Thirdly, we explored the role that SO2 would play if it were present as a co-injectant in carbon sequestration. The reaction considered is SO2 hydrolysis to form sulfurous acid. We expect the sulfurous acid will erode the calcite faster than carbonic acid because it is a stronger acid. Contrary to intuition, the simulation results showed a decrease in permeability due to CaSO3 precipitation in replacement of CaCO3, as CaSO3 has a larger molar volume.

In-depth survey report: Assisting furniture strippers in reducing the risk from methylene chloride stripping formulations at Los Angeles Stripping and Refinishing Center, Los Angeles, California

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

Estill, C.F.; Kovein, R.J.; Jones, J.H.

1999-03-26

The National Institute for Occupational Safety and Health (NIOSH) is currently conducting research on ventilation controls to reduce furniture stripping exposures to methylene chloride to the OSHA PEL of 25 ppm. Low cost ventilation systems were designed by NIOSH researchers along with Benny Bixenman of Benco Sales, Inc. (Forney, TX). The controls were constructed and installed by Benco Sales. This report compares the methylene chloride levels of one worker stripping furniture using the recently installed ventilation controls and using the existing controls. During the survey, two different chemical stripping solutions (a standard formulation and a low methylene chloride content formulation)more » were used and compared. This survey tested three control combinations: (1) new ventilation, low methylene chloride stripper, (2) new ventilation, standard stripping solution, and (3) old ventilation, standard stripping solution. During each test, sorbent tube sampling and real-time sampling were employed. Sorbent tube, data collected in the worker's breathing zone, ranged from 300 to 387 ppm. Real-time data showed breathing zone exposures to range from 211 to 383 ppm while stripping and 164 to 230 ppm while rinsing. Data were inconclusive to determine which ventilation system or stripping solution produced the lowest exposures. Recommendations are made in the report to improve the newly installed ventilation controls.« less

Comparison between active (pumped) and passive (diffusive) sampling methods for formaldehyde in pathology and histology laboratories.

PubMed

Lee, Eun Gyung; Magrm, Rana; Kusti, Mohannad; Kashon, Michael L; Guffey, Steven; Costas, Michelle M; Boykin, Carie J; Harper, Martin

2017-01-01

This study was to determine occupational exposures to formaldehyde and to compare concentrations of formaldehyde obtained by active and passive sampling methods. In one pathology and one histology laboratories, exposure measurements were collected with sets of active air samplers (Supelco LpDNPH tubes) and passive badges (ChemDisk Aldehyde Monitor 571). Sixty-six sample pairs (49 personal and 17 area) were collected and analyzed by NIOSH NMAM 2016 for active samples and OSHA Method 1007 (using the manufacturer's updated uptake rate) for passive samples. All active and passive 8-hr time-weighted average (TWA) measurements showed compliance with the OSHA permissible exposure limit (PEL-0.75 ppm) except for one passive measurement, whereas 78% for the active and 88% for the passive samples exceeded the NIOSH recommended exposure limit (REL-0.016 ppm). Overall, 73% of the passive samples showed higher concentrations than the active samples and a statistical test indicated disagreement between two methods for all data and for data without outliers. The OSHA Method cautions that passive samplers should not be used for sampling situations involving formalin solutions because of low concentration estimates in the presence of reaction products of formaldehyde and methanol (a formalin additive). However, this situation was not observed, perhaps because the formalin solutions used in these laboratories included much less methanol (3%) than those tested in the OSHA Method (up to 15%). The passive samplers in general overestimated concentrations compared to the active method, which is prudent for demonstrating compliance with an occupational exposure limit, but occasional large differences may be a result of collecting aerosolized droplets or splashes on the face of the samplers. In the situations examined in this study the passive sampler generally produces higher results than the active sampler so that a body of results from passive samplers demonstrating compliance with the OSHA PEL would be a valid conclusion. However, individual passive samples can show lower results than a paired active sampler so that a single result should be treated with caution.

The three youngest Plinian eruptions of Mt Pelée, Martinique (P1, P2 and P3): Constraining the eruptive conditions from field and experimental studies.

NASA Astrophysics Data System (ADS)

Kueppers, Ulrich; Uhlig, Joan; Carazzo, Guillaume; Kaminski, Edouard; Perugini, Diego; Tait, Steve; Clouard, Valérie

2015-04-01

Mt Pelée on Martinique, French Lesser Indies, is infamous for the last big Pelean (i.e., dome forming) eruption in 1902 AD that destroyed agricultural land and the city of Saint Pierre by pyroclastic density currents. Beside such mostly valley-confined deposits, the geological record shows thick fall deposits of at least three Plinian eruptions during the past 2000 years. In an attempt to describe and understand systematic eruptive behaviours as well as the associated variability of eruptive scenarios of Plinian eruptions in Martinique, we have investigated approx. 50 outcrops belonging to the P1 (1315 AD), P2 (345 AD) and P3 (4 AD) eruptions (Traineau et al., JVGR 1989) and collected bulk samples as well as >100 mm pumiceous clasts. All samples are andesitic, contain plagioclase and pyroxene in a glassy matrix and range in porosity between 55 and 69 vol.% with individual bubbles rarely larger than 1 mm. Our approach was two-fold: 1) Loose bulk samples have been subject to dry mechanical sieving in order to quantively describe the grain-size distribution and the fractal dimension. 2) From large clasts, 60*25 mm cylinders have been drilled for fragmentation experiments following the sudden decompression of gas in the sample's pore space. The used experimental set-up allowed for precisely controllable and repeatable conditions (5, 10 and 15 MPa, 25 °C) and the complete sampling of the generated pyroclasts. These experimentally generated clasts were analysed for their grain-size distribution and fractal dimension. For both natural samples and experimental populations, we find we find that the grain-size distribution follows a power-law, with an exponent between 2,5 and 3,7. Deciphering eruption conditions from deposits alone is challenging because of the complex interplay of dynamic volcanic processes and transport-related sorting. We use the quantified values of fractal dimension for a comparison of the power law exponents among the three eruptions and the laboratory results. This will contribute to an increased interpretability of well-preserved deposits and a critical evaluation of the limits.

Pectate lyase affects pathogenicity in natural isolates of Colletotrichum coccodes and in pelA gene-disrupted and gene-overexpressing mutant lines.

PubMed

Ben-Daniel, Bat-Hen; Bar-Zvi, Dudy; Tsror Lahkim, Leah

2012-02-01

Colletotrichum coccodes (Wallr.) S. Hughes, the causal agent of black dot on potato and anthracnose on tomato, reduces yield and crop quality. We explored the role of secreted pectate lyase (PL), a cell wall-degrading enzyme, in the aggressiveness of C. coccodes. In vitro-cultivated highly aggressive isolates secreted immunologically detectable PL levels 6 h after transfer to secondary medium versus 12 h for mildly aggressive isolates, suggesting that secreted PL is a virulence factor. The gene encoding PL, CcpelA, was cloned and used for the genetic manipulation of highly (US-41 and Si-72) and mildly (Si-60) aggressive isolates. CcpelA gene-disrupted mutants showed reduced aggressiveness towards tomato fruits and impaired PL secretion and extracellular activity. Conversely, overexpression of CcpelA in the Si-60 isolate increased its aggressiveness and PL secretion. Comparison of CcpelA cloned from isolates US-41 and Si-60 revealed that both encode identical proteins, but differ in their promoters. Bioinformatics analysis for cis-acting elements suggested that the promoters of the US-41 and Si-60 isolates contain one and no AreA-binding site (GATA box), respectively. AreA has been suggested to be involved in fungal aggressiveness; therefore, CcpelA may be a key virulence factor in C. coccodes pathogenicity, and the differences in isolate aggressiveness might result from promoter activity. Quantitative reverse transcriptase-polymerase chain reaction analyses confirmed the higher level of CcpelA transcript in isolate US-41 versus Si-60. © 2011 THE AUTHORS. MOLECULAR PLANT PATHOLOGY © 2011 BSPP AND BLACKWELL PUBLISHING LTD.

Newborn genome-wide DNA methylation in association with pregnancy anxiety reveals a potential role for GABBR1.

PubMed

Vangeel, Elise Beau; Pishva, Ehsan; Hompes, Titia; van den Hove, Daniel; Lambrechts, Diether; Allegaert, Karel; Freson, Kathleen; Izzi, Benedetta; Claes, Stephan

2017-01-01

There is increasing evidence for the role of prenatal stress in shaping offspring DNA methylation and disease susceptibility. In the current study, we aimed to identify genes and pathways associated with pregnancy anxiety using a genome-wide DNA methylation approach. We selected 22 versus 23 newborns from our Prenatal Early Life Stress (PELS) cohort, exposed to the lowest or highest degree of maternal pregnancy anxiety, respectively. Cord blood genome-wide DNA methylation was assayed using the HumanMethylation450 BeadChip (HM450, n  = 45) and candidate gene methylation using EpiTYPER ( n  = 80). Cortisol levels were measured at 2, 4, and 12 months of age to test infant stress system (re)activity. Data showed ten differentially methylated regions (DMR) when comparing newborns exposed to low versus high pregnancy anxiety scores. We validated a top DMR in the GABA-B receptor subunit 1 gene ( GABBR1 ) revealing the association with pregnancy anxiety particularly in male newborns (most significant CpG Pearson R  = 0.517, p  = 0.002; average methylation Pearson R  = 0.332, p  = 0.039). Cord blood GABBR1 methylation was associated with infant cortisol levels in response to a routine vaccination at 4 months old. In conclusion, our results show that pregnancy anxiety is associated with differential DNA methylation patterns in newborns and that our candidate gene GABBR1 is associated with infant hypothalamic-pituitary-adrenal axis response to a stressor. Our findings reveal a potential role for GABBR1 methylation in association with stress and provide grounds for further research.

Monitoring Volatile Organic Compounds (VOCs) in real-time on oil and natural gas production sites

NASA Astrophysics Data System (ADS)

Lupardus, R.; Franklin, S. B.

2017-12-01

Oil and Natural Gas (O&NG) development, production, infrastructure, and associated processing activities can be a substantial source of air pollution, yet relevant data and real-time quantification methods are lacking. In the current study, O&NG fugitive emissions of Volatile Organic Compounds (VOCs) were quantified in real-time and used to determine the spatial and temporal windows of exposure for proximate flora and fauna. Eleven O&NG sites on the Pawnee National Grassland in Northeastern Colorado were randomly selected and grouped according to production along with 13 control sites from three geographical locations. At each site, samples were collected 25 m from the wellhead in NE, SE, and W directions. In each direction, two samples were collected with a Gasmet DX4040 gas analyzer every hour from 8:00 am to 2:00 pm (6 hours total), July to October, 2016 (N=864). VOC concentrations generally increased during the 6 hr. day with the exception of N2O and were predominately the result of O&NG production and not vehicle exhaust. Thirteen of 24 VOCs had significantly different levels between production groups, frequently above reference standards and at biologically relevant levels for flora and fauna. The most biologically relevant VOCs, found at concentrations exceeding time weighted average permissible exposure limits (TWA PELs), were benzene and acrolein. Generalized Estimating Equations (GEEs) measured the relative quality of statistical models predicting benzene concentrations on sites. The data not only confirms that O&NG emissions are impacting the region, but also that this influence is present at all sites, including controls. Increased real-time VOC monitoring on O&NG sites is required to identify and contain fugitive emissions and to protect human and environmental health.

Characterization of the infrared spectra of serum from patients with multiple myeloma

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

Plotnikova, L., E-mail: ljusja@mail.ru; Nosenko, T.; Uspenskaya, M., E-mail: mv-uspenskaya@mail.ru

Multiple myeloma (MM) accounts for about 1% of all types of cancers. MM is characterized by the proliferation of a single clone of plasma cells, which may produce and secrete a homogeneous monoclonal immunoglobulin. The monoclonal immunoglobulin is commonly referred to as an M protein. The M protein acts as a serological “tumor” marker that is useful for diagnosis and disease monitoring. The electrophoretic pattern reveals the M-protein in 80% of MM patients as a single peak or localized band. In our study we applied a combination of high-resolution agarose gel protein electrophoresis (PEL), spectroscopic techniques and thermal analysis tomore » identify the key differences in protein composition, protein structure and their thermal behavior for the samples obtained from the serum of MM patients and healthy donors.« less

Spodoptera frugiperda (J.E. Smith) with field-evolved resistance to Bt maize are susceptible to Bt pesticides.

PubMed

Jakka, S R K; Knight, V R; Jurat-Fuentes, J L

2014-10-01

Field-evolved resistance to maize event TC1507 expressing the Cry1Fa toxin from Bacillus thuringiensis (Bt) was detected in populations of Spodoptera frugiperda from Puerto Rico. We tested for cross-resistance to purified Cry1A toxins and commercial Bt pesticides in susceptible (Benzon) and TC1507-resistant (456) strains of S. frugiperda. Larvae from the 456 strain exhibited cross-resistance to Cry1Ab and Cry1Ac toxins, while no differences in susceptibility to XenTari WG and DiPel ES pesticides were detected. These data support cross-resistance to toxins that share binding sites with Cry1Fa and no cross-resistance to Bt pesticides in S. frugiperda with field-evolved resistance to Bt maize. Copyright © 2014 Elsevier Inc. All rights reserved.

Assessment of dust exposure in a steel plant in the eastern coast of peninsular Malaysia.

PubMed

Nurul, Ainun Hamzah; Shamsul, Bahri Mohd Tamrin; Noor Hassim, Ismail

2016-11-22

Steel manufacturing produces dust, fumes, and pollutant gases that may give adverse health effects to the respiratory function of workers. Improper occupational hygiene practice in the workplace will affect both workers wellbeing and productivity. To assess the level of particulate matter [(PM2.5, PM10, and Total Particulate Matter (TPM)], and trace metal dust concentrations in different sections of a steel plant and compare with the occupational exposure values. The work environmental parameters of the particulate matters were evaluated using Indoor Air Quality, while metal dust concentrations were measured using portable personal air sampler. A total of 184 personal samples were randomly collected from workers in three major sections; steel making plant, direct reduced plant, and support group. Trace metal dust concentrations were subjected to wet mineral acid mixture digestion and analysed by atomic absorption spectrophotometer (AAS). The overall average PM2.5 concentration observed was varied according to the section: steel making plant was 0.18 mg/m3, direct reduced iron plant was 0.05 mg/m3, and support plant was 0.05 mg/m3. Average PM 10 concentration in steel making shop (SMS) plant, direct reduced (DR) plant, and support plant were 0.70 mg/m3, 0.84 mg/m3, and 0.58 mg/m3, respectively. The average TWA8 of trace metal dusts (cobalt and chromium) in all the sections exceeded 1 to 3 times the ACGIH prescribed values, OSHA PELs, NIOSH RELs as well as USECHH OSHA, whereas TWA8 concentration of nickel for each section did not exceed the occupational exposure values. The average PM2.5, PM10 and TPM did not exceed the prescribed values, while average trace metal dust concentration TWA8 for cobalt and chromium in all plants exceeded occupational exposure prescribed values. However, the nickel found did not exceed the prescribed values in all the plants except for NIOSH RELs.

Accumulation of as, pb, and cu associated with the recent sedimentary processes in the colorado delta, South of the United States-Mexico boundary.

PubMed

Daesslé, L W; Lugo-Ibarra, K C; Tobschall, H J; Melo, M; Gutiérrez-Galindo, E A; García-Hernández, J; Alvarez, L G

2009-05-01

Sediment cores from the Colorado River (CR) remnant delta were used to assess the changing sedimentation and pollutant deposition processes in response to extensive human manipulation of the river. The cores are formed of alternating layers of clays and silts, with isolated sandy horizons. The clayey units are interpreted as periods of flood flows into this low gradient and meandering estuary after dam construction in the United States. The geochemistry of these sediments is particular because of the association of MnO with CaO rather than with the Fe(2)O(3)-rich clays. Past pollution of the CR delta by As, and probably also Pb and Cu, is recorded in some cores. Enrichment factors (EFs) >1 for these elements and their statistical association suggest anthropogenic inputs. The most likely sources for these element enrichments (especially As) are the arsenate-based pesticides used intensively in the area during the first half of the 20th century. The transport of these elements from the nearby agricultural lands into the present river reaches appears to have been driven in part by flooding events of the CR. Flushing by river and tide flows appear to be responsible of a lower pollutant deposition in the CR compared to the adjacent Hardy River (HR). Arsenic in the buried clay units of the HR has concentrations above the probable toxic effect level (PEL) for dwelling organisms, with maximum concentrations of 30 microg g(-1). Excess (210)Pb activities ((210)Pb(xs)) indicate that fluxes of this unsupported atmospheric isotope were not constant in this estuarine environment. However, the presence of (210)Pb(xs) does indicate that these sediments accumulated during the last ~100 years. Aproximate sediment ages were estimated from the correlation of historic flooding events with the interpretation of the stratigraphic record. They are in fair agreement with the reported onset of DDT metabolites at the bottom of one core.

Source identification, environmental risk assessment and human health risks associated with toxic elements present in a coastal industrial environment, India.

PubMed

Satapathy, Shreemayee; Panda, C R

2018-03-26

This study investigated the source and contamination levels of toxic elements (Cd, Cr, As, Pb, Ni and Hg) present in a coastal environment, Paradip-an industrial hub of the east coast of India. The ecological risk assessment indices and human exposure models were used to evaluate the pollution status. Enrichment factor indicated that all the metal(loid)s found in the sediment are mostly derived from the anthropogenic source. According to the sediment quality quotient, 8.33% of sediments have crossed the ERM limit for Ni that can be fatal to biota. Meanwhile, 66.66, 41.66 and 8.33% of sediments have exceeded PEL range for Cr, Ni and As, respectively, that can register frequent lethal toxicity to benthic biota. As had the highest potential ecological harm coefficient (Er f  > 80), and Hg had moderate ecological harm coefficient (40 < Er f  < 80). Summarily, the sediment quality of this site is moderate to heavily toxic to benthic organisms. The concentration of toxic metals in seawater was below the permissible limit (CCC and CMC) set by USEPA indicating that water is relatively safer for free floating aquatic biota. The health risk index of toxic metal (loid)s present in soils of the residential sites has confirmed that there is a severe non-carcinogenic threat for children (HI child > 1) and a borderline carcinogenic risk for both adult and children. THQ Cr possesses highest non-carcinogenic threat, which contributed approximately 50% to HI followed by THQ As . The contribution of carcinogenic risk of chromium (CR Cr ) to TCR is approximately 60%. Cr is the significant contaminant of this site that has highest health effects. Highest exposure risks were associated with ingestion pathway accounting for about 85% of the total for most of the elements.

Cycloartane triterpenoid saponins from water soluble of Passiflora edulis Sims and their antidepressant-like effects.

PubMed

Wang, Cong; Xu, Feng-Qing; Shang, Jian-Hua; Xiao, Huai; Fan, Wei-Wei; Dong, Fa-Wu; Hu, Jiang-Miao; Zhou, Jun

2013-07-30

Various species of genus Passiflora have been used as traditional folk medicines owing to their sedative and anti-hypertensive properties. Passiflora edulis Sims most widely grown in the warm temperate for their fragrant fruits and their twigs and leaves are used as a folk medicine for treating both anxiety and nervousness in American countries. The present study was to evaluate the antidepressant-like effect and the active components of this plant. The alcohol extracts of the stems (PES, 10 and 2 g/kg of the plant materials) and leaves (PEL, 10 and 2 g/kg of the plant materials) of Passiflora edulis Sims were orally administered to mice for 7 day. The animals were tested in the forced swim test (FST) and tail suspension test (TST). After behavioral assay of ethanol extract, phytochemical research of the stems and leaves (5.7 kg) of Passiflora edulis Sims were developed and further bioactive verification of monomeric compounds were conducted. There are mainly cycloartane triterpenoids and their saponins isolated from this plant, including two new cycloartane triterpenoid saponins named cyclopassifloside ХII (1) and ХIII (2), together with six known cycloartane triterpenoids, cyclopassifloic acids B and E, cyclopassiflosides II, VI, IX and XI. The ethanol extract of Passiflora edulis Sims together with isolated compounds cyclopassiflosides IX and XI may possess antidepressant-like effect. Cycloartane triterpenoid was one of the main compositions of Passiflora edulis Sims and possess antidepressant-like activity. Crown Copyright © 2013. Published by Elsevier Ireland Ltd. All rights reserved.

Exposure Assessment of a High-energy Tensile Test With Large Carbon Fiber Reinforced Polymer Cables.

PubMed

Schlagenhauf, Lukas; Kuo, Yu-Ying; Michel, Silvain; Terrasi, Giovanni; Wang, Jing

2015-01-01

This study investigated the particle and fiber release from two carbon fiber reinforced polymer cables that underwent high-energy tensile tests until rupture. The failing event was the source of a large amount of dust whereof a part was suspected to be containing possibly respirable fibers that could cause adverse health effects. The released fibers were suspected to migrate through small openings to the experiment control room and also to an adjacent machine hall where workers were active. To investigate the fiber release and exposure risk of the affected workers, the generated particles were measured with aerosol devices to obtain the particle size and particle concentrations. Furthermore, particles were collected on filter samples to investigate the particle shape and the fiber concentration. Three situations were monitored for the control room and the machine hall: the background concentrations, the impact of the cable failure, and the venting of the exposed rooms afterward. The results showed four important findings: The cable failure caused the release of respirable fibers with diameters below 3 μm and an average length of 13.9 μm; the released particles did migrate to the control room and to the machine hall; the measured peak fiber concentration of 0.76 fibers/cm(3) and the overall fiber concentration of 0.07 fibers/cm(3) in the control room were below the Permissible Exposure Limit (PEL) for fibers without indication of carcinogenicity; and the venting of the rooms was fast and effective. Even though respirable fibers were released, the low fiber concentration and effective venting indicated that the suspected health risks from the experiment on the affected workers was low. However, the effect of long-term exposure is not known therefore additional control measures are recommended.

Divergence of a strain of Pseudomonas aeruginosa during an outbreak of ovine mastitis.

PubMed

Wright, Elli A; Di Lorenzo, Valeria; Trappetti, Claudia; Liciardi, Manuele; Orru, Germano; Viti, Carlo; Bronowski, Christina; Hall, Amanda J; Darby, Alistair C; Oggioni, Marco R; Winstanley, Craig

2015-01-30

Bacterial infections causing mastitis in sheep can result in severe economic losses for farmers. A large survey of milk samples from ewes with mastitis in Sardinia, Italy, indicated an increasing prevalence of Pseudomonas aeruginosa infections. It has been shown previously that during chronic, biofilm-associated infections P. aeruginosa populations diversify. We report the phenotypic and genomic characterisation of two clonal P. aeruginosa isolates (PSE305 and PSE306) from a mastitis infection outbreak, representing distinct colony morphology variants. In addition to pigment production, PSE305 and PSE306 differed in phenotypic characteristics including biofilm formation, utilisation of various carbon and nitrogen sources, twitching motility. We found higher levels of expression of genes associated with biofilm formation (pelB) and twitching motility (flgD) in PSE305, compared to the biofilm and twitching-defective PSE306. Comparative genomics analysis revealed single nucleotide polymorphisms (SNPs) and minor insertion/deletion variations between PSE305 and PSE306, including a SNP mutation in the pilP gene of PSE306. By introducing a wild-type pilP gene we were able to partially complement the defective twitching motility of PSE306. There were also three larger regions of difference between the two genomes, indicating genomic instability. Hence, we have demonstrated that P. aeruginosa population divergence can occur during an outbreak of mastitis, leading to significant variations in phenotype and genotype, and resembling the behaviour of P. aeruginosa during chronic biofilm-associated infections. Copyright © 2014 Elsevier B.V. All rights reserved.

Efficacies of quorum sensing inhibitors, piericidin A and glucopiericidin A, produced by Streptomyces xanthocidicus KPP01532 for the control of potato soft rot caused by Erwinia carotovora subsp. atroseptica.

PubMed

Kang, Ji Eun; Han, Jae Woo; Jeon, Byeong Jun; Kim, Beom Seok

2016-03-01

To discover potential inhibitors of the quorum sensing (QS) system, a library of microbial culture extracts was screened with Chromobacterium violaceumCV026 strain. The culture extract of Streptomyces xanthocidicus KPP01532 contained quorum-sensing inhibitors (QSIs) of the CV026 strain. The active constituents of the culture extract of strain KPP01532 were purified using a series of chromatographic procedures, and based on data from NMR and mass spectroscopy, piericidin A and glucopiericidin A were identified. Erwinia carotovora subsp. atroseptica (Eca) is a plant pathogen that causes blackleg and soft rot diseases on potato stems and tubers. The virulence factors of Eca are regulated by QS. The expression of virulence genes (pelC, pehA, celV and nip) under the control of QS was monitored using quantitative real-time PCR (qRT-PCR). The transcription levels of the four genes were significantly lower when Eca was exposed to piericidin A or glucopiericidin A. These two compounds displayed similar control efficacies against soft rot caused by Eca in potato slices as furanone C-30. Therefore, piericidin A and glucopiericidin A are potential QSIs that suppress the expression of the virulence genes of Eca, suggesting that they could have potential use as control agents of soft rot disease on potato tubers. Copyright © 2015 Elsevier GmbH. All rights reserved.

Cementogenic potential of multipotential mesenchymal stem cells purified from the human periodontal ligament.

PubMed

Torii, Daisuke; Konishi, Kiyoshi; Watanabe, Nobuyuki; Goto, Shinichi; Tsutsui, Takeki

2015-01-01

The periodontal ligament (PDL) consists of a group of specialized connective tissue fibers embedded in the alveolar bone and cementum that are believed to contain progenitors for mineralized tissue-forming cell lineages. These progenitors may contribute to regenerative cell therapy or tissue engineering methods aimed at recovery of tissue formation and functions lost in periodontal degenerative changes. Some reports using immortal clonal cell lines of cementoblasts, which are cells containing mineralized tissue-forming cell lineages, have shown that their phenotypic alteration and gene expression are associated with mineralization. Immortal, multipotential PDL-derived cell lines may be useful biological tools for evaluating differentiation-inducing agents. In this study, we confirmed the gene expression and mineralization potential of primary and immortal human PDL cells and characterized their immunophenotype. Following incubation with mineralization induction medium containing β-glycerophosphate, ascorbic acid, and dexamethasone, normal human PDL (Pel) cells and an immortal derivative line (Pelt) cells showed higher levels of mineralization compared with cells grown in normal growth medium. Both cell types were positive for putative surface antigens of mesenchymal cells (CD44, CD73, CD90, and CD105). They were also positive for stage-specific embryonic antigen-3, a marker of multipotential stem cells. Furthermore, PDL cells expressed cementum attachment protein and cementum protein 1 when cultured with recombinant human bone morphogenetic protein-2 or -7. The results suggest that normal and immortal human PDL cells contain multipotential mesenchymal stem cells with cementogenic potential.

Indoor air quality in hairdressing salons in Taipei.

PubMed

Chang, C-J; Cheng, S-F; Chang, P-T; Tsai, S-W

2018-01-01

To improve indoor air quality and to protect public health, Taiwan has enacted the "Indoor Air Quality Act (IAQ Act)" in 2012. For the general public, the indoor air quality in hair salons is important because it is a popular location that people will often visit for hair treatments. However, only a few exposure assessments regarding air pollutants have previously been performed in hair salons. To assess the air quality of hairdressing environments in Taipei, ten hairdressing salons were included for a walk-through survey in this study. In addition, the airborne concentrations of formaldehyde, volatile organic compounds (VOCs), CO 2 , and phthalate esters were also determined in 5 salons. Charcoal, XAD-2, and OVS-Tenax tubes were used for the air sampling, while the samples were analyzed with gas chromatography/mass spectrometer. It was found that the products used in hair salons contained various chemicals. In fact, from the walk-through survey, a total of 387 different ingredients were found on 129 hair product labels. The hair salons were not well ventilated, with CO 2 levels of 600 to 3576 ppm. The formaldehyde concentrations determined in this study ranged from 12.40 to 1.04 × 10 3  μg m -3 , and the maximum level was above the permissible exposure limit (PEL) of US Occupational Safety and Health Administration (US OSHA). Additionally, 83% of the samples were with levels higher than the standard regulated by Taiwan's IAQ Act. The concentrations of VOCs and phthalate esters were below the occupational exposure limits (OELs), but higher than what was found in general residential environments. The hair products were considered as the major source of air pollutants because significantly higher concentrations were found around the working areas. The number of perming treatments, the number of workers, and the frequency of using formaldehyde releasing products, were found to be associated with the levels of formaldehyde. This study indicates that efforts are needed to improve the indoor air quality in hairdressing salons in Taipei. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

A progressive data compression scheme based upon adaptive transform coding: Mixture block coding of natural images

NASA Technical Reports Server (NTRS)

Rost, Martin C.; Sayood, Khalid

1991-01-01

A method for efficiently coding natural images using a vector-quantized variable-blocksized transform source coder is presented. The method, mixture block coding (MBC), incorporates variable-rate coding by using a mixture of discrete cosine transform (DCT) source coders. Which coders are selected to code any given image region is made through a threshold driven distortion criterion. In this paper, MBC is used in two different applications. The base method is concerned with single-pass low-rate image data compression. The second is a natural extension of the base method which allows for low-rate progressive transmission (PT). Since the base method adapts easily to progressive coding, it offers the aesthetic advantage of progressive coding without incorporating extensive channel overhead. Image compression rates of approximately 0.5 bit/pel are demonstrated for both monochrome and color images.

An Optoelectronic Nose for Detection of Toxic Gases

PubMed Central

Lim, Sung H.; Feng, Liang; Kemling, Jonathan W.; Musto, Christopher J.; Suslick, Kenneth S.

2009-01-01

We have developed a simple colorimetric sensor array (CSA) for the detection of a wide range of volatile analytes and applied it to the detection of toxic gases. The sensor consists of a disposable array of cross-responsive nanoporous pigments whose colors are changed by diverse chemical interactions with analytes. Although no single chemically responsive pigment is specific for any one analyte, the pattern of color change for the array is a unique molecular fingerprint. Clear differentiation among 19 different toxic industrial chemicals (TICs) within two minutes of exposure at IDLH (immediately dangerous to life or health) concentration has been demonstrated. Quantification of each analyte is easily accomplished based on the color change of the array, and excellent detection limits have been demonstrated, generally below the PELs (permissible exposure limits). Identification of the TICs was readily achieved using a standard chemometric approach, i.e., hierarchical clustering analysis (HCA), with no misclassifications over 140 trials. PMID:20160982

Recombinant expression and characterization of L-asparaginase II from a moderately thermotolerant bacterial isolate.

PubMed

Vidya, Jalaja; Pandey, Ashok

2012-07-01

A moderately thermotolerant bacterium belonging to Enterobacteriaceae, which can grow at 44.5 °C, was isolated from cow dung; L-asparaginase II gene was isolated by PCR, cloned, and expressed in pET 20b with pelB leader sequence and 6× Histidine tag at the C-terminal end. The active protein from the soluble sonicated fraction was purified through nickel affinity chromatography. After characterization, the purified protein showed optimum activities at a temperature of 37 °C and in a buffer system of pH 6 to 7. The enzyme exhibited thermostability at 50 °C with a 33% and 28% of activity retention after 45 and 60 min. The kinetic parameters for the enzyme were calculated from Lineweaver-Burk plot, and K(m) and V(max) were 0.89 mM and 0.18 U/mg, respectively.

Establishment of an ELISA to detect Kaposi's sarcoma-associated herpesvirus using recombinant ORF73.

PubMed

Ouyang, Xin-xing; Fu, Bi-shi; Li, Bao-lin; Zeng, Yan; Xu, Fan-hong; Wang, Lin-ding

2010-06-01

Kaposi's sarcoma-associated herpesvirus (KSHV) is causally related to Kaposi's sarcoma (KS), primary effusion lymphoma (PEL) and a proportion of cases of multicentric Castleman's disease (MCD). The ORF73 protein was cloned into pQE80L-orf73 and expressed in E.coli and purified. The expressed recombinant ORF73 was identified by sodium dodecyl sulfatepolyacrylamide gel electrophoresis (SDS-PAGE). A protein of about 27 kDa was expressed as expected. Western Blotting showed that the purified recombinant ORF73 reacted with KSHV positive serum. The immunogenicity of the recombinant ORF73 was further analysed by ELISA and the optimal conditions were determined. The ORF73 ELISA was used to compare the KSHV seroprevalence between Hubei and Xinjiang Han people. The Han people in Xinjiang have significantly higher KSHV seroprevalence than their counterparts in Hubei (6.7% vs 2.9%, P = 0.005).

Surveillance of occupational noise exposures using OSHA's Integrated Management Information System.

PubMed

Middendorf, Paul J

2004-11-01

Exposure to noise has long been known to cause hearing loss, and is an ubiquitous problem in workplaces. Occupational noise exposures for industries stored in the Occupational Safety and Health Administration's (OSHA) Integrated Management Information System (IMIS) can be used to identify temporal and industrial trends of noise exposure to anticipate changes in rates of hearing loss. The noise records in OSHA's IMIS database for 1979-1999 were extracted by major industry division and measurement criteria. The noise exposures were summarized by year, industry, and employment size. The majority of records are from Manufacturing and Services. Exposures in Manufacturing and Services have decreased during the period, except that PEL exposures measured by federal enforcement increased from 1995 to 1999. Noise exposures in manufacturing have been reduced since the late 1970s, except those documented by federal enforcement. Noise exposure data outside manufacturing is not well represented in IMIS. Copyright 2004 Wiley-Liss, Inc.

Automating the AFROTC Four-Year Scholarship Program.

DTIC Science & Technology

1986-04-01

ATCH 2 b1 C -d C4 4" %C N 0" cl4 es C4 CN 1 onin %DG C1 06 0 -0 40 V 44-4 LIU-4- c4 A: U. -4 La 4 E vt a-’ iv El "l 04 0 0.I t b U El 4 V do v 0 CoU. -4...CEEB CLAS~S BOARD 1ST 2ND DCF QEP/ STRT,"’ HWFADC CfI3; PEL SCORES SCORE COMP SCOPE STAND RAMK".,H~DC ’ PREF PREF RACE PREY" rTL B1 = 46/1 C hiroms...A/N 88 Fencing 4 AIN 89 La Crosse 4 AIN 90 Rifle/Pistol 4 AIN 91 Rugby 4 AIN 92 Track 4 A/N 93 Wrestling 4 A/N 94 Others (Name and Codes) 15 A/N 95

Kaposi's sarcoma-associated herpesvirus-encoded interleukin-6.

PubMed

Aoki, Y; Jones, K D; Tosato, G

2000-04-01

Since the discovery of the virus in 1994, the rapid pace with which Karposi's sarcoma-associated herpesvirus (KSHV) research has progressed has quickly led to a broad understanding of the structure of the virus and its biology and pathology in humans. Molecular piracy of potentially useful cellular genes has emerged as a characteristic feature of this virus. The viral homolog of human IL-6, vIL-6 is an example in kind. Studies in vitro and in vivo have shown that vIL-6 can stimulate the growth of KSHV-infected primary infusion lymphoma (PEL) cells, can promote hematopoiesis, and act as an angiogenic factor through the induction of vascular endothelial growth factor (VEGF). It is not difficult to envision how vIL-6, through these properties and perhaps others yet to be identified, can contribute to KSHV survival and spread in the human population.

Mechanics governs single-cell signaling and multi-cell robustness in biofilm infections

NASA Astrophysics Data System (ADS)

Gordon, Vernita

In biofilms, bacteria and other microbes are embedded in extracellular polymers (EPS). Multiple types of EPS can be produced by a single bacterial strain - the reasons for this redundancy are not well-understood. Our work suggests that different polymers may confer distinct mechanical benefits. Our model organism is Pseudomonas aeruginosa, an opportunistic human pathogen that forms chronic biofilm infections associated with increased antibiotic resistance and evasion of the immune defense. Biofilms initiate when bacteria attach to a surface, sense the surface, and change their gene expression. Changes in gene expression are regulated by a chemical signal, cyclic-di-GMP. We find that one EPS material, called ``PEL,'' enhances surface sensing by increasing mechanical coupling of single bacteria to the surface. Measurements of bacterial motility suggest that PEL may increase frictional interactions between the surface and the bacteria. Consistent with this, we show that bacteria increase cyclic-di-GMP signaling in response to mechanical shear stress. Mechanosensing has long been known to be important to the function of cells in higher eukaryotes, but this is one of only a handful of studies showing that bacteria can sense and respond to mechanical forces. For the mature biofilm, the embedding polymer matrix can protect bacteria both chemically and mechanically. P. aeruginosa infections in the cystic fibrosis (CF) lung often last for decades, ample time for the infecting strain(s) to evolve. Production of another EPS material, alginate, is well-known to tend to increase over time in CF infections. Alginate chemically protects biofilms, but also makes them softer and weaker. Recently, it is being increasingly recognized that bacteria in chronic CF infections also evolve to increase PSL production. We use oscillatory bulk rheology to determine the unique contributions of EPS materials to biofilm mechanics. Unlike alginate, increased PSL stiffens biofilms. Increasing both PSL and alginate expression increases the energy cost to break the biofilm. We compare the elastic moduli of biofilms to estimated stresses exerted by phagocytotic immune cells, and infer that increased PSL could confer a mechanical fitness benefit. This work was supported by start-up funds from The University of Texas at Austin and a gift from ExxonMobile to VDG, and by Grants from the Human Frontiers Science Program (HFSP RGY0081/2012-GORDON) and the National Science Foundation (NSF 1337670).

Exposures to asbestos arising from bandsawing gasket material.

PubMed

Fowler, D P

2000-05-01

A simulation of bandsawing sheet asbestos gasket material was performed as part of a retrospective exposure evaluation undertaken to assist in determining causation of a case of mesothelioma. The work was performed by bandsawing a chrysotile asbestos (80%)/neoprene gasket sheet with a conventional 16-inch woodworking bandsaw inside a chamber. Measurements of airborne asbestos were made using conventional area and personal sampling methods, with analysis of collected samples by transmission electron microscopy (TEM) and phase contrast microscopy (PCM). These were supplemented by qualitative scanning electron microscopy (SEM) examinations of some of the airborne particles collected on the filters. In contrast with findings from studies examining manual handling (installation and removal) of gaskets, airborne asbestos concentrations from this operation were found to be well above current Occupational Safety and Health Administration (OSHA) permissible exposure limit (PEL) (eight-hour time-weighted average [TWA]) and excursion limit (30-minute) standards. Although some "encapsulation" effect of the neoprene matrix was seen on the particles in the airborne dust, unencapsulated individual fiber bundles were also seen. Suggestions for the implications of the work are given. In summary, the airborne asbestos concentrations arising from this work were quite high, and point to the need for careful observation of common sense precautions when manipulation of asbestos-containing materials (even those believed to have limited emissions potential) may involved machining operations.

Source and Fate of Sediments in the Bahia de Anasco, Puerto Rico

NASA Astrophysics Data System (ADS)

Webb, R. M.

2005-12-01

Sediments and wastewater mix in the insular marine waters of the Bah'{i}a de Añasco near Mayag{u}ez, Puerto Rico. Trace metal concentrations in fine sediments deposited in the bay were measured to assess potential impact of the ocean outfall on the biota and habitats that include coral reefs. A Q-mode factor analysis of elemental compositions identified three sediment sources and their relative proportions in 51 core and surficial samples collected from the bay and within the coral reefs: (1) sediments discharged by the R'{i}o Grande de Añasco; (2) calcareous skeletal remains; and (3) sediments discharged by the R'{i}o Guanajibo. The nickel and chromium derived from laterite deposits provide a unique fingerprint for sediments discharged from the R'{i}o Guanajibo. Naturally occurring concentrations of these elements exceed Probable Effect Limits (PEL's: 42 mg/kg for nickel and 160 mg/kg for chromium) in sediments deposited near the river mouth. The detection of mercury at 1 mg/kg in one sample from a core recovered near the wastewater outfall was the only indication of a possible outfall source in the data set. The temporal and spatial variations in source fractions proved useful in determining relative frequencies of historic floods and steady-state circulation patterns off the west coast of Puerto Rico.

Evaluation of the toxicity and efficacy of hydrogen peroxide treatments on eggs of warm and cool water fishes

USGS Publications Warehouse

Rach, J.J.; Gaikowski, M.P.; Howe, G.E.; Schreier, Theresa M.

1998-01-01

The use of hydrogen peroxide in aquaculture is growing and there is a need to develop fundamental guidelines to effectively treat diseased fish. The safety (toxicity) of hydrogen peroxide treatments was determined on eggs of representative warm- and coolwater fish species. Eggs of northern pike (Esox lucius), walleye (Stizostedion vitreum), yellow perch (Pel ca flavescens), white sucker (Catostomus commersoni), lake sturgeon (Acipenser fulvescens), paddlefish (Polyodon spathula), common carp (Cyprinus carpio), and channel catfish (Ictalurus punctatus) were cultured in egg jars or aquaria. Treatments were initiated with non-eyed eggs and continued until all viable eggs had hatched. Eggs were treated daily for 15 min Monday through Friday with either 0, 500, 1000, 3000, or 6000 mu l l(-1) of hydrogen peroxide. For all species, the mean percent hatch was greater in eggs treated with 1000 mu l l(-1) hydrogen peroxide for 15 min than in the untreated controls. Common carp, lake sturgeon, and paddlefish were the least sensitive to hydrogen peroxide with percent hatch ranging from 40 to 48% in the 6000 mu l l(-1) hydrogen peroxide treatment. Fungal infections reduced or eliminated the hatch in most controls whereas nearly all treated eggs remained free of infection; hydrogen peroxide inhibited fungal infections on fish eggs. (C) 1998 Elsevier Science B.V. All rights reserved.

Air Quality measurements near the Gulf of Mexico Deep Water Horizon Oil Spill site in July 2010

NASA Astrophysics Data System (ADS)

Schade, G. W.; Rasmussen, R.; Conlee, D.; Seroka, G.; Delao, D.

2010-12-01

Eight whole air samples were acquired within several kilometers of the Deepwater Horizon well head location between 5 and 13 July 2010. A Teflon coated pump was used to pressurize 0.8 L volume stainless steel canisters to approximately 2 bar. Various amounts of oil were visible on the water surface during most sampling times, and some samples were accompanied by strong hydrocarbon smells. The air samples were analyzed over the next two months using high sensitivity GC-FID and GC-MS methods for C1-C30 hydrocarbons and selected hetero-atomic compounds. Highest concentrations reached several ppm for total hydrocarbons, comparable to concentrations in highway road tunnels. None of the samples showed elevated concentrations suggestive of hazardous concentrations, or near OSHA PEL or NIOSH REL levels. Consistent with studies of seawater methane concentrations at different depths, atmospheric methane mixing ratios were close to background abundances at 1.75-1.78 ppm, suggesting that the spill’s methane emissions had not reached the surface at that time. Non-methane hydrocarbons presented a highly complex mixture (100+ species) of dominantly alkanes, as expected. Linear alkanes were detected at elevated mixing ratios from C4 up to C30, and were dominated by nonane (C9). Aromatic hydrocarbons showed a pattern suggestive of a significant retention by seawater of benzene and toluene, the compounds with the highest water solubilities. While benzene was hardly and toluene only slightly elevated, lower solubility compounds such as the xylenes and naphthalene were clearly elevated. Data will be presented relative to an upwind sample taken on 5 July.

pH Regulation of Pectate Lyase Secretion Modulates the Attack of Colletotrichum gloeosporioides on Avocado Fruits†

PubMed Central

Yakoby, Nir; Kobiler, Ilana; Dinoor, Amos; Prusky, Dov

2000-01-01

Growth of Colletotrichum gloeosporioides in pectolytic enzyme-inducing medium (PEIM) increased the pH of the medium from 3.8 to 6.5. Pectate lyase (PL) secretion was detected when the pH reached 5.8, and the level of secretion increased up to pH 6.5. PL gene (pel) transcript production began at pH 5.0 and increased up to pH 5.7. PL secretion was never detected when the pH of the inducing medium was lower than 5.8 or when C. gloeosporioides hyphae were transferred from PL-secreting conditions at pH 6.5 to pH 3.8. This behavior differed from that of polygalacturonase (PG), where pg transcripts and protein secretion were detected at pH 5.0 and continued up to 5.7. Under in vivo conditions, the pH of unripe pericarp of freshly harvested avocado (Persea americana cv. Fuerte) fruits, resistant to C. gloeosporioides attack, was 5.2, whereas in ripe fruits, when decay symptoms were expressed, the pericarp pH had increased to 6.3. Two avocado cultivars, Ardit and Ettinger, which are resistant to C. gloeosporioides attack, had pericarp pHs of less than 5.5, which did not increase during ripening. The present results suggest that host pH regulates the secretion of PL and may affect C. gloeosporioides pathogenicity. The mechanism found in avocado may have equivalents in other postharvest pathosystems and suggests new approaches for breeding against and controlling postharvest diseases. PMID:10698767

Evaluation of Needle Gun and Abrasive Blasting Technologies in Bridge Paint Removal Practices.

PubMed

Randall, Paul M; Kranz, Paul B; Sonntag, Mary L; Stadelmaier, James E

1998-03-01

This paper reviews the results of a U.S. Environmental Protection Agency (EPA) study that assessed needle gun technology as an alternative to conventional abrasive blasting technology to remove lead-based paint from steel bridges in western New York State. The study analyzed the operational and logistical aspects as they relate to worker health and safety, environmental protection, hazardous waste generation, and costs as compared to those arising from conventional abrasive blasting. In this 1992 EPA study, the costs and the product quality aspects favored conventional abrasive blasting over the needle gun technology for removing lead paint. However, abrasive blasting exposed workers to airborne lead levels that exceeded Permissible Exposure Limits (PELs) as established by the Occupational Safety and Health Administration (OSHA), as well as emitting high levels of lead-contaminated dusts and debris into the environment. It was estimated that more than 500 lbs of lead-contaminated spent abrasives and paint waste were released into the environment during paint removal operations. The needle gun system reduced (up to 97.5%) the generation of hazardous waste and the airborne concentrations (up to 99%) of respirable dusts and lead-containing particulates generated during paint removal operations. However, labor costs for the needle gun were three times higher than those for abrasive blasting primarily because of slower production rates that necessitated more operating personnel. The higher labor costs of the needle gun are partially offset by the increased costs associated with the expendable abrasive blast media and hazardous waste disposal. In the EPA study, the productivity of the needle gun system was 12.2 ft 2 /hr vs. 147.5 ft 2 /hr for abrasive blasting. A post blast was needed for the needle gun system to meet surface preparation specifications. When factoring in the costs of full containment structures to meet OSHA's 1993 Lead Exposure in Construction regulation, the needle gun system has the potential to be economically competitive with conventional abrasive blasting.

Combat vehicle crew helmet-mounted display: next generation high-resolution head-mounted display

NASA Astrophysics Data System (ADS)

Nelson, Scott A.

1994-06-01

The Combat Vehicle Crew Head-Mounted Display (CVC HMD) program is an ARPA-funded, US Army Natick Research, Development, and Engineering Center monitored effort to develop a high resolution, flat panel HMD for the M1 A2 Abrams main battle tank. CVC HMD is part of the ARPA High Definition Systems (HDS) thrust to develop and integrate small (24 micrometers square pels), high resolution (1280 X 1024 X 6-bit grey scale at 60 frame/sec) active matrix electroluminescent (AMEL) and active matrix liquid crystal displays (AMLCD) for head mounted and projection applications. The Honeywell designed CVC HMD is a next generation head-mounted display system that includes advanced flat panel image sources, advanced digital display driver electronics, high speed (> 1 Gbps) digital interconnect electronics, and light weight, high performance optical and mechanical designs. The resulting dramatic improvements in size, weight, power, and cost have already led to program spin offs for both military and commercial applications.

[Small-cell lung cancer: epidemiology, diagnostics and therapy].

PubMed

Pešek, Miloš; Mužík, Jan

Authors present actual overview of information on diagnostic and therapeutic procedures in small-cell lung cancer (SCLC). This highly aggressive type of lung cancer is diagnosed in 14.8 % of Czech lung cancer patients. Vast majority of those patients (87 %) suffer from advanced and metastatic disease in the time of diagnosis. In this issue are presented prognostic factors, staging diagnostic procedures and therapeutic recommendations. The backbone of actual SCLC treatment is combined chemotherapy and radiotherapy and less frequently, carefully in selected cases, surgical procedures. SCLC should be have as chemosensitive, chemoresistent or chemorefractory disease. Actual cytostatic combinations used in 1st line treatment, different schedules of chemoradiotherapy, drugs used in second line treatment and schedules and timing of prophylactic brain irradiation are presented. In near future, perspectively, there are some promissible data on antitumour immunotherapy based on anti CTLA-4 and anti PD-1/PE-L1 antibodies also in SCLC patients.Key words: cancer immunotherapy - concomitant chemoradiotherapy - chemotherapy - chest radiotherapy - lung resections - prophylactic brain irradiation - small cell lung cancer.

Formaldehyde Exposures in a University Anatomy Laboratory

NASA Astrophysics Data System (ADS)

Winkler, Kyle William

Air sampling studies were conducted within a university anatomical laboratory during the embalmment of a cadaver in order to determine if dangerous concentrations of formaldehyde existed. Three air sampling studies were conducted in the anatomical laboratory on three separate days that a cadaver was being embalmed. Samples were collected and analyzed using the Occupational Safety and Health Administration (OSHA) Sampling and Analytical Methods: Method 52. Each air sampling study sampled for short term exposure limit (STEL) and time weighted mean (TWA) breathing zone formaldehyde concentrations as well as area TWA formaldehyde concentrations. A personal aldehyde monitor was also used in each air sampling study to sample for breathing zone formaldehyde concentrations. Measured TWA mean exposures to formaldehyde ranged from 0.15--1.3 parts per million (ppm), STEL formaldehyde exposures ranged from 0.019--0.64 ppm, and eight-hour TWAs ranged from 0.03 to 3.6 ppm. All 8-hour TWA formaldehyde concentrations sampled in the anatomy laboratory during an embalmment were less than the permissible exposure limit (PEL) required by OSHA.

Late Holocene Peléan-style eruption at Tacaná volcano, Mexico and Guatemala: past, present, and future hazards

USGS Publications Warehouse

Macías, J. L.; Espíndola, J. M.; Garcia-Palomo, A.; Scott, K.M.; Hughes, S.; Mora, J C.

2000-01-01

Tacaná volcano, located on the border between Mexico and Guatemala, marks the northern extent of the Central American volcanic chain. Composed of three volcanic structures, it is a volcanic complex that has had periodic explosive eruptions for at least the past 40 k.y. The most recent major eruption occurred at the San Antonio volcano, the youngest volcanic edifice forming the complex, about 1950 yr ago. The Peléan style eruption, issued from the southwest part of the dome, and swept a 30° sector with a hot block and ash flow that traveled about 14 km along the Cahoacán ravine. Deposits from this event are well exposed around the town of Mixcun and were therefore given the name of that town, the Mixcun flow deposit. The Mixcun flow deposit is, in the channel facies, a light gray, massive, thick (>10 m), matrix-supported unit with dispersed lithic clasts of gravel to boulder size, divisible in some sections into a variable number of flow units. The overbank facies is represented by a thin (2 and has a minimum estimated volume of 0.12 km3. Basaltic-andesite inclusions (54% SiO2) and various signs of disequilibrium in the mineral assemblage of the two-pyroxene andesitic products (60%–63% SiO2) suggest that magma mixing may have triggered the eruption. Following deposition of the Mixcun flow deposit andesitic to dacitic (62%–64% SiO2) lava flows were extruded and a dacitic dome (64.4% SiO2) at the San Antonio summit formed. Syn-eruptive and posteruptive lahars flooded the main drainages of the Cahoacán and Izapa-Mixcun valleys in the area of the present city of Tapachula (population 250000) and the pre-Hispanic center of Izapa. Three radiocarbon ages date this event between A.D. 25 and 72 (range ±1σ, 38 B.C.–A.D. 216), which correlates with a halt in construction at Izapa (Hato phase of ca. 50 B.C.–A.D. 100), probably due to temporary abandonment of the city caused by lahars. Another similar event would produce extensive damage to the towns (population of about 68,000 people) now built upon the Mixcun flow deposit. The main summit of Tacaná volcano continues to show signs of fumarolic activity; the most recent period of activity in 1985–1986 culminated in a minor phreatic explosion.

Role of large flank-collapse events on magma evolution of volcanoes. Insights from the Lesser Antilles Arc

NASA Astrophysics Data System (ADS)

Boudon, Georges; Villemant, Benoît; Friant, Anne Le; Paterne, Martine; Cortijo, Elsa

2013-08-01

Flank-collapse events are now recognized as common processes of destruction of volcanoes. They may occur several times on a volcanic edifice pulling out varying volumes of material from km3 to thousands of km3. In the Lesser Antilles Arc, a large number of flank-collapse events were identified. Here, we show that some of the largest events are correlated to significant variations in erupted magma compositions and eruptive styles. On Montagne Pelée (Martinique), magma production rate has been sustained during several thousand years following a 32 ka old flank-collapse event. Basic and dense magmas were emitted through open-vent eruptions that generated abundant scoria flows while significantly more acidic magmas were produced before the flank collapse. The rapid building of a new cone increased the load on magma bodies at depth and the density threshold. Magma production rate decreased and composition of the erupted products changed to more acidic compared to the preceding period of activity. These low density magma generated plinian and dome-forming eruptions up to the Present. In contrast at Soufrière Volcanic Centre of St. Lucia and at Pitons du Carbet in Martinique, the flank-collapses have an opposite effect: in both cases, the acidic magmas erupted immediately after the flank-collapses. These magmas are highly porphyritic (up to 60% phenocrysts) and much more viscous than the magmas erupted before the flank-collapses. They have been generally emplaced as voluminous and uptight lava domes (called “the Pitons”). Such magmas could not ascent without a significant decrease of the threshold effect produced by the volcanic edifice loading before the flank-collapse.

Identification and Molecular Characterization of Genes Coding Pharmaceutically Important Enzymes from Halo-Thermo Tolerant Bacillus

PubMed Central

Safary, Azam; Moniri, Rezvan; Hamzeh-Mivehroud, Maryam; Dastmalchi, Siavoush

2016-01-01

Purpose: Robust pharmaceutical and industrial enzymes from extremophile microorganisms are main source of enzymes with tremendous stability under harsh conditions which make them potential tools for commercial and biotechnological applications. Methods: The genome of a Gram-positive halo-thermotolerant Bacillus sp. SL1, new isolate from Saline Lake, was investigated for the presence of genes coding for potentially pharmaceutical enzymes. We determined gene sequences for the enzymes laccase (CotA), l-asparaginase (ansA3, ansA1), glutamate-specific endopeptidase (blaSE), l-arabinose isomerase (araA2), endo-1,4-β mannosidase (gmuG), glutaminase (glsA), pectate lyase (pelA), cellulase (bglC1), aldehyde dehydrogenase (ycbD) and allantoinases (pucH) in the genome of Bacillus sp. SL1. Results: Based on the DNA sequence alignment results, six of the studied enzymes of Bacillus sp. SL-1 showed 100% similarity at the nucleotide level to the same genes of B. licheniformis 14580 demonstrating extensive organizational relationship between these two strains. Despite high similarities between the B. licheniformis and Bacillus sp. SL-1 genomes, there are minor differences in the sequences of some enzyme. Approximately 30% of the enzyme sequences revealed more than 99% identity with some variations in nucleotides leading to amino acid substitution in protein sequences. Conclusion: Molecular characterization of this new isolate provides useful information regarding evolutionary relationship between B. subtilis and B. licheniformis species. Since, the most industrial processes are often performed in harsh conditions, enzymes from such halo-thermotolerant bacteria may provide economically and industrially appealing biocatalysts to be used under specific physicochemical situations in medical, pharmaceutical, chemical and other industries. PMID:28101462

Identification and Molecular Characterization of Genes Coding Pharmaceutically Important Enzymes from Halo-Thermo Tolerant Bacillus.

PubMed

Safary, Azam; Moniri, Rezvan; Hamzeh-Mivehroud, Maryam; Dastmalchi, Siavoush

2016-12-01

Purpose: Robust pharmaceutical and industrial enzymes from extremophile microorganisms are main source of enzymes with tremendous stability under harsh conditions which make them potential tools for commercial and biotechnological applications. Methods: The genome of a Gram-positive halo-thermotolerant Bacillus sp. SL1, new isolate from Saline Lake, was investigated for the presence of genes coding for potentially pharmaceutical enzymes. We determined gene sequences for the enzymes laccase (CotA), l-asparaginase (ansA3, ansA1), glutamate-specific endopeptidase (blaSE), l-arabinose isomerase (araA2), endo-1,4-β mannosidase (gmuG), glutaminase (glsA), pectate lyase (pelA), cellulase (bglC1), aldehyde dehydrogenase (ycbD) and allantoinases (pucH) in the genome of Bacillus sp. SL1. Results: Based on the DNA sequence alignment results, six of the studied enzymes of Bacillus sp. SL-1 showed 100% similarity at the nucleotide level to the same genes of B. licheniformis 14580 demonstrating extensive organizational relationship between these two strains. Despite high similarities between the B. licheniformis and Bacillus sp. SL-1 genomes, there are minor differences in the sequences of some enzyme. Approximately 30% of the enzyme sequences revealed more than 99% identity with some variations in nucleotides leading to amino acid substitution in protein sequences. Conclusion: Molecular characterization of this new isolate provides useful information regarding evolutionary relationship between B. subtilis and B. licheniformis species. Since, the most industrial processes are often performed in harsh conditions, enzymes from such halo-thermotolerant bacteria may provide economically and industrially appealing biocatalysts to be used under specific physicochemical situations in medical, pharmaceutical, chemical and other industries.

GEOSCOPE network : continuous recording over 29 years

NASA Astrophysics Data System (ADS)

Pardo, C.; Bonaime, S.; Stutzmann, E.; Maggi, A.; Team, G.; Geoscope Team

2011-12-01

The GEOSCOPE observatory was created in 1982 and has now provided the scientific community with nearly 30 years of continuous broadband recordings . The 33 GEOSCOPE stations are installed in 19 countries, across all continents and on islands throughout the oceans. They are equipped with three component very broadband seismometers (STS1 or STS2) and 24 or 26 bit digitizers. Progressively stations are being equipped with warpless base plates which decrease long period noise on horizontal components by up to 15dB. In most stations, a pressure gauge and a thermometer are also installed. In 2011, 3 stations have been upgraded: COYC and PEL in Chile and ATD in Djibouti. Two new stations have been installed in Ivituut (station IVI, Greenland, GLISN project) and in Vanuatu islands (station SANVU). Currently, 27 stations transmit data in real or near real time to the GEOSCOPE Data Center and to tsunami warning centers. Continuous data from all stations are collected by the GEOSCOPE Data Center in Paris where they are validated, archived and made available to the international scientific community. Data are freely available to users via different interfaces according to data type (http://geoscope.ipgp.fr). We provide continuous data in real time through the seedlink protocol, validated continuous waveforms through the NetDC system and Data Handler Interface, a selection of large earthquake seismograms through the geoscope web portal. GEOSCOPE/IPGP is one of the four primary nodes of EIDA (European Integrated Data Archive) and our data are accessible through (http://www.seismicportal.eu). Noise levels for the last 20 years of continuous data are also accessible via the geoscope web site. Stations in both hemispheres show stronger noise amplitude during local winter except for the station DRV which is surrounded by sea ice in winter.

Exposure to airborne asbestos during removal and installation of gaskets and packings: a review of published and unpublished studies.

PubMed

Madl, Amy K; Clark, Katherine; Paustenbach, Dennis J

2007-01-01

In recent years, questions have been raised about the health risks to persons who have been occupationally exposed to asbestos-containing gaskets and packing materials used in pipes, valves, and machinery (pumps, autos, etc.). Up until the late 1970s, these materials were widely used throughout industrial and maritime operations, refineries, chemical plants, naval ships, and energy plants. Seven simulation studies and four work-site industrial hygiene studies of industrial and maritime settings involving the collection of more than 300 air samples were evaluated to determine the likely airborne fiber concentrations to which a worker may have been exposed while working with encapsulated asbestos-containing gaskets and packing materials. Each study was evaluated for the representativeness of work practices, analytical methods, sample size, and potential for asbestos contamination (e.g., insulation on valves or pipes used in the study). Specific activities evaluated included the removal and installation of gaskets and packings, flange cleaning, and gasket formation. In all but one of the studies relating to the replacement of gaskets and packing using hand-held tools, the short-term average exposures were less than the current 30-min OSHA excursion limit of 1 fiber per cubic centimeter (f/cc) and all of the long-term average exposures were less than the current 8-h permissible exposure limit time-weighted average (PEL-TWA) of 0.1 f/cc. The weight of evidence indicates that the use of hand tools and hand-operated power tools to remove or install gaskets or packing as performed by pipefitters or other tradesmen in nearly all plausible situations would not have produced airborne concentrations in excess of contemporaneous regulatory levels.

[The airborne 1,3-butadiene concentrations in rubber and plastic processing plants].

PubMed

Yoshida, Toshiaki; Tainaka, Hidetsugu; Matsunaga, Ichiro; Goto, Sumio

2002-03-01

Environment pollution by 1,3-butadiene had considerably increased in Japan. The main cause of the pollution is the automotive exhaust gas, and leaks from factories, smoking, and burning of rubber and plastic products are considered to be minor sources. The object of this study was to determine the contamination levels of airborne 1,3-butadiene in factories processing rubber and plastics containing 1,3-butadiene. The concentrations of airborne 1,3-butadiene were measured in 21 plants (10 rubber processing plants and 11 plastics processing plants) in Osaka. 1,3-Butadiene in air was collected for 10 minutes with a charcoal tube and a portable small pump adjusted to a 250 ml/min flow rate. In each plant, indoor air samples at five points and an outdoor air sample at one point outside the plant were collected. The samples were subjected to gas chromatography/mass spectrometry after thermal desorption from the charcoal. The concentrations of airborne 1,3-butadiene in the rubber processing plants and the plastics processing plants were 0.14-2.20 micrograms/m3 (geometric mean: 0.48 microgram/m3) and 0.23-4.51 micrograms/m3 (geometric mean: 0.80 microgram/m3), respectively. In all plants examined, indoor 1,3-butadiene concentrations were higher than the outdoor concentrations around the plants. Therefore, 1,3-butadiene was considered to arise from the processing of rubber or plastics, but the indoor 1,3-butadiene concentrations were much lower than the PEL-TWA (1 ppm = 2.21 mg/m3) of OSHA and the TLV-TWA (2 ppm) of ACGIH. The concentrations in the plants with closed room conditions without ventilation were higher than the concentrations in the other plants. It was suggested that ventilation affected the 1,3-butadiene concentration in the plants.

OSHA's approach to risk assessment for setting a revised occupational exposure standard for 1,3-butadiene.

PubMed Central

Grossman, E A; Martonik, J

1990-01-01

In its 1980 benzene decision [Industrial Union Department, ALF-CIO v. American Petroleum Institute, 448 U.S. 607 (1980)], the Supreme Court ruled that "before he can promulgate any permanent health or safety standard, the Secretary [of Labor] is required to make a threshold finding that a place of employment is unsafe--in the sense that significant risks are present and can be lessened by a change in practices" (448 U.S. at 642). The Occupational Safety and Health Administration (OSHA) has interpreted this to mean that whenever possible, it must quantify the risk associated with occupational exposure to a toxic substance at the current permissible exposure limit (PEL). If OSHA determines that there is significant risk to workers' health at its current standard, then it must quantify the risk associated with a variety of alternative standards to determine at what level, if any, occupational exposure to a substance no longer poses a significant risk. For rulemaking on occupational exposure to 1,3-butadiene, there are two studies that are suitable for quantitative risk assessment. One is a mouse inhalation bioassay conducted by the National Toxicology Program (NTP), and the other is a rat inhalation bioassay conducted by Hazelton Laboratories Europe. Of the four risk assessments that have been submitted to OSHA, all four have used the mouse and/or rat data with a variety of models to quantify the risk associated with occupational exposure to 1,3-butadiene. In addition, OSHA has performed its own risk assessment using the female mouse and female rat data and the one-hit and multistage models.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2401254

Tailored adhesion behavior of polyelectrolyte thin films deposited on plasma-treated poly(dimethylsiloxane) for functionalized membranes

NASA Astrophysics Data System (ADS)

Bassil, Joelle; Alem, Halima; Henrion, Gérard; Roizard, Denis

2016-04-01

Completely homogenous films formed via the layer-by-layer assembly of poly(diallyldimethylammonium chloride) (PDADMAC) and the poly(styrene sulfonate) were successfully obtained on plasma-treated poly(dimethylsiloxane) (PDMS) substrates. To modify the hydrophobicity of the PDMS surface, a cold plasma treatment was previously applied to the membrane, which led to the creation of hydrophilic groups on the surface of the membrane. PDMS wettability and surface morphology were successfully correlated with the plasma parameters. A combination of contact angle measurements, scanning electron microscopy (SEM) and atomic force microscopy (AFM) analysis was used to demonstrate that homogeneous and hydrophilic surfaces could be achieved on PDMS cold-plasma-treated membranes. The stability of the assembled PEL layer on the PDMS was evaluated using a combination of pull-off testing and X-ray photoelectron spectroscopy (XPS), which confirmed the relevance of a plasma pre-treatment as the adhesion of the polyelectrolyte multilayers was greatly enhanced when the deposition was completed on an activated PDMS surface at 80 W for 5 min.

Secretory expression of nattokinase from Bacillus subtilis YF38 in Escherichia coli.

PubMed

Liang, Xiaobo; Jia, Shifang; Sun, Yufang; Chen, Meiling; Chen, Xiuzhu; Zhong, Jin; Huan, Liandong

2007-11-01

Nattokinase producing bacterium, B. subtilis YF38, was isolated from douchi, using the fibrin plate method. The gene encoding this enzyme was cloned by polymerase chain reaction (PCR). Cytoplasmic expression of this enzyme in E. coli resulted in inactive inclusion bodies. But with the help of two different signal peptides, the native signal peptide of nattokinase and the signal peptide of PelB, active nattokinase was successfully expressed in E. coli with periplasmic secretion, and the nattokinase in culture medium displayed high fibrinolytic activity. The fibrinolytic activity of the expressed enzyme in the culture was determined to reach 260 urokinase units per micro-liter when the recombinant strain was induced by 0.7 mmol l(-1) isopropyl-beta-D- thiogalactopyranoside (IPTG) at 20 degrees C for 20 h, resulting 49.3 mg active enzyme per liter culture. The characteristic of this recombinant nattokinase is comparable to the native nattokinase from B. subtilis YF38. Secretory expression of nattokinase in E. coli would facilitate the development of this enzyme into a therapeutic product for the control and prevention of thrombosis diseases.

A phage display vector optimized for the generation of human antibody combinatorial libraries and the molecular cloning of monoclonal antibody fragments.

PubMed

Solforosi, Laura; Mancini, Nicasio; Canducci, Filippo; Clementi, Nicola; Sautto, Giuseppe Andrea; Diotti, Roberta Antonia; Clementi, Massimo; Burioni, Roberto

2012-07-01

A novel phagemid vector, named pCM, was optimized for the cloning and display of antibody fragment (Fab) libraries on the surface of filamentous phage. This vector contains two long DNA "stuffer" fragments for easier differentiation of the correctly cut forms of the vector. Moreover, in pCM the fragment at the heavy-chain cloning site contains an acid phosphatase-encoding gene allowing an easy distinction of the Escherichia coli cells containing the unmodified form of the phagemid versus the heavy-chain fragment coding cDNA. In pCM transcription of heavy-chain Fd/gene III and light chain is driven by a single lacZ promoter. The light chain is directed to the periplasm by the ompA signal peptide, whereas the heavy-chain Fd/coat protein III is trafficked by the pelB signal peptide. The phagemid pCM was used to generate a human combinatorial phage display antibody library that allowed the selection of a monoclonal Fab fragment antibody directed against the nucleoprotein (NP) of Influenza A virus.

Exposures to thoracic particulate matter, endotoxin, and glucan during post-Hurricane Katrina restoration work, New Orleans 2005-2012.

PubMed

Rando, Roy J; Kwon, Cheol-Woong; Lefante, John J

2014-01-01

In the aftermath of Hurricane Katrina, which devastated the city of New Orleans in August 2005, restoration workers were at risk for respiratory illness from exposure to airborne particles and microbial agents. In support of an epidemiologic investigation of this risk, an exposure assessment for restoration work activities (demolition, trash & debris management, landscape restoration, sewer/waterline repair, and mold remediation) was performed from 2005 to 2012. For 2005 and 2006, Occupational Safety and Health Administration (OSHA) data (n = 730) for personal and area monitoring of total and respirable dust exposures of restoration workers were accessed and analyzed. The most significant exposures were for demolition work, with average respirable dust exposures in 2005 above the action level of 2.5 mg/m(3) and 17.6% of exposures exceeding the permissible exposure limit (PEL) (5 mg/m(3)). Additional personal and area monitoring for thoracic particulate matter was performed from 2007 to 2012 (n = 774) and samples were assayed for endotoxin and (1→3, 1→6)-β-D-glucan (n = 202). In order to integrate the OSHA data with the later monitoring data, three independent predictive models were developed to convert total and respirable dust measures into the equivalent thoracic dust. The three models were not statistically different and the modeling results were in good agreement with an overall coefficient of variation of 16% for the thoracic dust means across work activities estimated by each of the three models. Overall, thoracic dust exposure levels decreased by about an order of magnitude within the first year after Katrina and then more gradually declined and stabilized through 2012. Estimated average exposures to endotoxin and microbial glucan in 2005 were as high as 256 EU/m(3) and 118 μg/m(3), respectively, and likewise were seen to decrease dramatically and stabilize after 2005. The results of this exposure assessment support previously published reports of respiratory illness including sinusitis, toxic pneumonitis, and Katrina Cough among restoration workers in the years immediately after the hurricane.

Final Report on Portable Laser Coating Removal Systems Field Demonstrations and Testing

NASA Technical Reports Server (NTRS)

Rothgeb, Matthew J.; McLaughlin, Russell L.

2008-01-01

Processes currently used throughout the National Aeronautics and Space Administration (NASA) to remove corrosion and coatings from structures, ground service equipment and small components results in waste streams consisting of toxic chemicals, spent media blast materials, and waste water. When chemicals are used in these processes they are typically high in volatile organic compounds (VOC) and are considered hazardous air pollutants (HAP). When blast media is used, the volume of hazardous waste generated is increased significantly. Many of the coatings historically used within NASA contain toxic metals such as hexavalent chromium, and lead. These materials are highly regulated and restrictions on worker exposure continue to increase. Most recently the EPA reduced the permissible exposure limit (PEL) for hexavalent chromium. The new standard lowers OSHA's PEL for hexavalent chromium from 52 to 5 micrograms of Cr(V1) per cubic meter of air as an 8-hour time-weighted average. Hexavalent chromium is found in the pretreatment and primer coatings used within the Shuttle Program. In response to the need to continue to protect assets within the agency and the growing concern over these new regulations, NASA is researching different ways to continue the required maintenance of both facility and flight equipment in a safe, efficient and environmentally preferable manner. The use of laser energy to remove prepare surfaces for a variety of processes, such as corrosion and coating removal, weld preparation and non destructive evaluation is a relatively new technology that has shown itself to be environmentally preferable and in many cases less labor intensive than currently used removal methods. The development of a Portable Laser Coating Removal System (PLCRS) started as the goal of a Joint Group on Pollution Prevention (JG-PP) project, led by the Air Force, where several types of lasers in several configurations were thoroughly evaluated. Following this project, NASA decided to evaluate the best performers on processes and coatings specific to the agency. Laser systems used during this project were all of a similar design, most of which had integrated vacuum systems in order to collect materials removed from substrate surfaces during operation. Due to the fact that the technology lends itself to a bide variety of processes, several site demonstrations were organized in order to allow for greater evaluation of the laser systems across NASA. The project consisted of an introductory demonstration and a more in-depth evaluation at Wright-Patterson Air Force Base. Additionally, field demonstrations occurred at Glenn Research Center and Kennedy Space Center. During these demonstrations several NASA specific applications were evaluated, including the removal of coatings within Orbiter tile cavities and Teflon from Space Shuttle Main Engine gaskets, removal of heavy grease from Solid Rocket Booster components and the removal of coatings on weld lines for Shuttle and general ground service equipment for non destructive evaluation (NDE). In addition, several general industry applications such as corrosion removal, structural coating removal, weld-line preparation and surface cleaning were evaluated. This included removal of coatings and corrosion from surfaces containing lead-based coatings and applications similar to launch-structure maintenance and Crawler maintenance. During the project lifecycle, an attempt was made to answer process specific concerns and questions as they arose. Some of these initially unexpected questions concerned the effects lasers might have on substrates used on flight equipment including strength, surface re-melting, substrate temperature and corrosion resistance effects. Additionally a concern was PPE required for operating such a system including eye, breathing and hearing protection. Most of these questions although not initially planned, were fully explored as a part of this project. Generally the results from tesng were very positive. Corrosion was effectively removed from steel, but less successfully from aluminum alloys. Coatings were able to be removed, with varying results, generally dark, matte and thin coatings were easier to remove. Steel and aluminum panels were able to be cleaned for welding, with no known deleterious effects and weld-lines were able to have coatings removed in critical areas for NDE while saving time as compared to other methods.

Stratigraphy of the 1902 and 1929 nuée-ardente deposits, Mt. Pelée, Martinique

NASA Astrophysics Data System (ADS)

Bourdier, J. L.; Boudon, G.; Gourgaud, A.

1989-08-01

Mild nuée ardentes in 1902-1903 and 1929-1930 at Mt. Pelée formed high-aspect ratio (H.A.R.) deposits (i.e. deposits with a high thickness/extent ratio) in the Rivière Blanche channel. Several violent nuées ardentes from May to August, 1902, yielded low aspect ratio (L.A.R.) deposits unevenly blanketing an area of 58 km 2 on the southwestern flank of the volcano. Three closely spaced nuées ardentes on August 30 additionally affected 56 km 2 on the southeastern flank. The L.A.R. deposits are divided into eight stratigraphic units (U1-U8), either compound or consisting of a single flow unit. The deposits of the largest nuées ardentes, on May 8, 20 and August 30, 1902 are identified as U1, U3 and U8, respectively, and can be traced over most of the area. Individual L.A.R. flow units are lenticular and show large, erratic lateral variations of thickness and grain-size. Most flow units consist of three distinct beds: Bed 1 is a few centimeters thick, lenticular, fines-depleted layer. Bed 2 is the thickest layer and contains more silt-sized ash than bed 1. It is normally graded as a whole, though reverse grading may occur in the lower part. Bed 2 generally consists of two parts: bed 2a, nonbedded, and bed 2b, finer-grained and laminated with cross-bedding and duned structures. Bed 3 is a thin, silty, capping layer which contains accretionary lapilli. The distribution of the L.A.R. flow units, especially of the coarse-grained facies, suggests that they were formed from overpressured blast-flows expanding radially from the vent at a high rate, in the same manner as the laterally directed blast of Mount St. Helens on May 18, 1980. The transport system of the major 1902 nuées ardentes was an inflated, relatively low-concentration, turbulent cloud as suggested by several lines of evidence: (1) the transported material was able to cross ridges up to 300 m high; (2) many scour-and-fill and other erosional features can be observed in the deposits at any distance from the vent; (3) survivors within the devastated area on May 8 did not experience a dense, low-profile cloud but instead a choking, hot ash-laden cloud; (4) many human corpses in St. Pierre remained where they fell instead of having floated away. If the current flow-surge terminology were to be used, the 1902 blast-flows would be better considered as pyroclastic surges. The normally graded, multi-layered structure of the flow units is also consistent with deposits primarily formed from relatively low-concentration flows.

Synthetic vitreous fibers: a review of toxicology research and its impact on hazard classification.

PubMed

Hesterberg, T W; Hart, G A

2001-01-01

Because the inhalation of asbestos, a naturally occurring, inorganic fibrous material, is associated with lung fibrosis and thoracic cancers, concerns have been raised about the possible health effects of synthetic vitreous fibers (SVFs). SVFs include a very broad variety of inorganic fibrous materials with an amorphous molecular structure. Traditionally, SVFs have been divided into three subcategories based on composition: fiberglass, mineral wool (rock, stone, and slag wools), and refractory ceramic fiber. For more than 50 years, the toxicologic potential of SVFs has been researched extensively using human epidemiology and a variety of laboratory studies. Here we review the research and its impact on hazard classification and regulation of SVFs. Large, ongoing epidemiology studies of SVF manufacturing workers have provided very little evidence of harmful effects in humans. Several decades of research using rodents exposed by inhalation have confirmed that SVF pulmonary effects are determined by the "Three D's", fiber dose (lung), dimension, and durability. Lung dose over time is determined by fiber deposition and biopersistence in the lung. Deposition is inversely related to fiber diameter. Biopersistence is directly related to fiber length and inversely related to fiber dissolution and fragmentation rates. Inhaled short fibers are cleared from the lung relatively quickly by mobile phagocytic cells, but long fibers persist until they dissolve or fragment. In contrast to asbestos, most of the SVFs tested in rodent inhalation studies cleared rapidly from the lung (were nonbiopersistent) and were innocuous. However, several relativley biopersistent SVFs induced chronic inflammation, lung scarring (fibrosis), and thoracic neoplasms. Thus, biopersistence of fibers is now generally recognized as a key determinant of the toxicologic potential of SVFs. In vitro dissolution of fibers in simulated extracellular fluid correlates fairly well with fiber biopersistence in the lung and pulmonary toxicity, but several exceptions suggest that biopersistence involves more than dissolution rate. Research demonstrating the relationship between biopersistence and SVF toxicity has provided a scientific basis for hazard classification and regulation of SVFs. For a nonhazardous classification, legislation recently passed by the European Union requires a respirable insulation wool to have a low lung-biopersistence or be noncarcinogenic in laboratory rats. U.S. fiberglass and mineral wool industries and the Occupational Health and Safety Administration (OSHA) have formed a voluntary Health and Safety Partnership Program (HSPP) that include: a voluntary permissible exposure level (PEL) in the workplace of 1 fiber/cc, a respiratory protection program for specified tasks, continued workplace air monitoring, and, where possible, the development of fiber formulations that do not persist in the lung. RCF manufacturers have implemented a Product Stewardship Program that includes: a recommended exposure guideline of 0.5 fibers/cc; a 5-year workplace air monitoring program; and research into the development of high-temperature-resistant, biosoluble fibers.

Biological and health effects of exposure to kerosene-based jet fuels and performance additives.

PubMed

Ritchie, Glenn; Still, Kenneth; Rossi, John; Bekkedal, Marni; Bobb, Andrew; Arfsten, Darryl

2003-01-01

Over 2 million military and civilian personnel per year (over 1 million in the United States) are occupationally exposed, respectively, to jet propulsion fuel-8 (JP-8), JP-8 +100 or JP-5, or to the civil aviation equivalents Jet A or Jet A-1. Approximately 60 billion gallon of these kerosene-based jet fuels are annually consumed worldwide (26 billion gallon in the United States), including over 5 billion gallon of JP-8 by the militaries of the United States and other NATO countries. JP-8, for example, represents the largest single chemical exposure in the U.S. military (2.53 billion gallon in 2000), while Jet A and A-1 are among the most common sources of nonmilitary occupational chemical exposure. Although more recent figures were not available, approximately 4.06 billion gallon of kerosene per se were consumed in the United States in 1990 (IARC, 1992). These exposures may occur repeatedly to raw fuel, vapor phase, aerosol phase, or fuel combustion exhaust by dermal absorption, pulmonary inhalation, or oral ingestion routes. Additionally, the public may be repeatedly exposed to lower levels of jet fuel vapor/aerosol or to fuel combustion products through atmospheric contamination, or to raw fuel constituents by contact with contaminated groundwater or soil. Kerosene-based hydrocarbon fuels are complex mixtures of up to 260+ aliphatic and aromatic hydrocarbon compounds (C(6) -C(17+); possibly 2000+ isomeric forms), including varying concentrations of potential toxicants such as benzene, n-hexane, toluene, xylenes, trimethylpentane, methoxyethanol, naphthalenes (including polycyclic aromatic hydrocarbons [PAHs], and certain other C(9)-C(12) fractions (i.e., n-propylbenzene, trimethylbenzene isomers). While hydrocarbon fuel exposures occur typically at concentrations below current permissible exposure limits (PELs) for the parent fuel or its constituent chemicals, it is unknown whether additive or synergistic interactions among hydrocarbon constituents, up to six performance additives, and other environmental exposure factors may result in unpredicted toxicity. While there is little epidemiological evidence for fuel-induced death, cancer, or other serious organic disease in fuel-exposed workers, large numbers of self-reported health complaints in this cohort appear to justify study of more subtle health consequences. A number of recently published studies reported acute or persisting biological or health effects from acute, subchronic, or chronic exposure of humans or animals to kerosene-based hydrocarbon fuels, to constituent chemicals of these fuels, or to fuel combustion products. This review provides an in-depth summary of human, animal, and in vitro studies of biological or health effects from exposure to JP-8, JP-8 +100, JP-5, Jet A, Jet A-1, or kerosene.

Activation of DNA Damage Response Induced by the Kaposi’s Sarcoma-Associated Herpes Virus

PubMed Central

Di Domenico, Enea Gino; Toma, Luigi; Bordignon, Valentina; Trento, Elisabetta; D’Agosto, Giovanna; Cordiali-Fei, Paola; Ensoli, Fabrizio

2016-01-01

The human herpes virus 8 (HHV-8), also known as Kaposi sarcoma-associated herpes virus (KSHV), can infect endothelial cells often leading to cell transformation and to the development of tumors, namely Kaposi’s sarcoma (KS), primary effusion lymphoma (PEL), and the plasmablastic variant of multicentric Castleman’s disease. KSHV is prevalent in areas such as sub-Saharan Africa and the Mediterranean region presenting distinct genotypes, which appear to be associated with differences in disease manifestation, according to geographical areas. In infected cells, KSHV persists in a latent episomal form. However, in a limited number of cells, it undergoes spontaneous lytic reactivation to ensure the production of new virions. During both the latent and the lytic cycle, KSHV is programmed to express genes which selectively modulate the DNA damage response (DDR) through the activation of the ataxia telangiectasia mutated (ATM) pathway and by phosphorylating factors associated with the DDR, including the major tumor suppressor protein p53 tumor suppressor p53. This review will focus on the interplay between the KSHV and the DDR response pathway throughout the viral lifecycle, exploring the putative molecular mechanism/s that may contribute to malignant transformation of host cells. PMID:27258263

Pseudomonas biofilm matrix composition and niche biology

PubMed Central

Mann, Ethan E.; Wozniak, Daniel J.

2014-01-01

Biofilms are a predominant form of growth for bacteria in the environment and in the clinic. Critical for biofilm development are adherence, proliferation, and dispersion phases. Each of these stages includes reinforcement by, or modulation of, the extracellular matrix. Pseudomonas aeruginosa has been a model organism for the study of biofilm formation. Additionally, other Pseudomonas species utilize biofilm formation during plant colonization and environmental persistence. Pseudomonads produce several biofilm matrix molecules, including polysaccharides, nucleic acids, and proteins. Accessory matrix components shown to aid biofilm formation and adaptability under varying conditions are also produced by pseudomonads. Adaptation facilitated by biofilm formation allows for selection of genetic variants with unique and distinguishable colony morphology. Examples include rugose small-colony variants and wrinkly spreaders (WS), which over produce Psl/Pel or cellulose, respectively, and mucoid bacteria that over produce alginate. The well-documented emergence of these variants suggests that pseudomonads take advantage of matrix-building subpopulations conferring specific benefits for the entire population. This review will focus on various polysaccharides as well as additional Pseudomonas biofilm matrix components. Discussions will center on structure–function relationships, regulation, and the role of individual matrix molecules in niche biology. PMID:22212072

Effects of conversion of mangroves into gei wai ponds on accumulation, speciation and risk of heavy metals in intertidal sediments.

PubMed

Li, Rongyu; Qiu, Guo Yu; Chai, Minwei; Shen, Xiaoxue; Zan, Qijie

2018-06-23

Mangroves are often converted into gei wai ponds for aquaculture, but how such conversion affects the accumulation and behavior of heavy metals in sediments is not clear. The present study aims to quantify the concentration and speciation of heavy metals in sediments in different habitats, including gei wai pond, mangrove marsh dominated by Avicennia marina and bare mudflat, in a mangrove nature reserve in South China. The results showed that gei wai pond acidified the sediment and reduced its electronic conductivity and total organic carbon (TOC) when compared to A. marina marsh and mudflat. The concentrations of Cd, Cu, Zn and Pb at all sediment depths in gei wai pond were lower than the other habitats, indicating gei wai pond reduced the fertility and the ability to retain heavy metals in sediment. Gei wai pond sediment also had a lower heavy metal pollution problem according to multiple evaluation methods, including potential ecological risk coefficient, potential ecological risk index, geo-accumulation index, mean PEL quotients, pollution load index, mean ERM quotients and total toxic unit. Heavy metal speciation analysis showed that gei wai pond increased the transfer of the immobilized fraction of Cd and Cr to the mobilized one. According to the acid-volatile sulfide (AVS) and simultaneously extracted metals (SEM) analysis, the conversion of mangroves into gei wai pond reduced values of ([SEM] - [AVS])/f oc , and the role of TOC in alleviating heavy metal toxicity in sediment. This study demonstrated the conversion of mangrove marsh into gei wai pond not only reduced the ecological purification capacity on heavy metal contamination, but also enhanced the transfer of heavy metals from gei wai pond sediment to nearby habitats.

Human Health and Performance Considerations for Exploration of Near-Earth Asteroids

NASA Technical Reports Server (NTRS)

Kundrot, Craig; Steinberg, Susan; Charles, John

2010-01-01

This presentation will describe the human health and performance issues that are anticipated for the human exploration of near-Earth asteroids (NEA). Humans are considered a system in the design of any such deep-space exploration mission, and exploration of NEA presents unique challenges for the human system. Key factors that define the mission are those that are strongly affected by distance and duration. The most critical of these is deep-space radiation exposure without even the temporary shielding of a nearby large planetary body. The current space radiation permissible exposure limits (PEL) restrict mission duration to 3-10 months depending on age and gender of crewmembers and stage of the solar cycle. Factors that affect mission architecture include medical capability; countermeasures for bone, muscle, and cardiovascular atrophy during continuous weightlessness; restricted food supplies; and limited habitable volume. The design of a habitat that can maintain the physical and psychological health of the crew and support mission operations with limited intervention from Earth will require an integrated research and development effort by NASA s Human Research Program, engineering, and human factors groups. Limited abort and return options for an NEA mission are anticipated to have important effects on crew psychology as well as influence medical supplies and training requirements of the crew. Other important factors are those related to isolation, confinement, communication delays, autonomous operations, task design, small crew size, and even the unchanging view outside the windows for most of the mission. Geological properties of the NEA will influence design of sample handling and containment, and extravehicular activity capabilities including suit ports and tools. A robotic precursor mission that collects basic information on NEA surface properties would reduce uncertainty about these aspects of the mission as well as aid in design of mission architecture and exploration tasks.

A trial of the use of pedobarography in the assessment of the effectiveness of rehabilitation in patients with coxarthrosis.

PubMed

Rongies, Witold; Bak, Agata; Lazar, Andrzej; Dolecki, Włodzimierz; Kolanowska-Kenczew, Tomira; Sierdziński, Janusz; Spychała, Andrzej; Krakowiecki, Arkadiusz

2009-01-01

Pedobarography is an evidence-based diagnostic method that allows quantitative, qualitative and repeatable measurement of pressures on every square centimetre of the sole area of the foot as well as centre of gravity sway, with graphic and numerical recording of results. The aim of the study was to assess the progress of a selected model of rehabilitation on the basis of subpedal pressure distribution and centre of gravity sway in pedobarographic examination as well as to evaluate changes in pain intensity in patients with a history of coxarthrosis. The study included 21 patients with Altman grade 2 coxarthrosis. A postural pedobarographic examination was performed immediately before and after a 15-day course of rehabilitation with a PEL 38 electronic pedobarograph and computer image analyser with TWINN 99 software, version 2.08. Following the rehabilitation, the study group displayed a statistically significant reduction in pain intensity, improved balance between the average and maximum subpedal pressures of both feet as well as a decrease in the velocity of centre of gravity sway. 1. A correlation between reduced pain intensity and improved balance of loads on both feet, as well as decreased velocity of centre of gravity sway were observed in the study group after the rehabilitation. 2. The pedobarographic examination may become a new method of diagnosis and follow-up in rehabilitation. 3. Pedobarography, owing to its ease of repeatability and non-invasiveness, may constitute a valuable attempt at objective monitoring of the progress of rehabilitation and its results. 4. The study results encourage further research based on a larger cohort of patients and a control group with a multi-stage prospective design.

Removal of copper ions from aqueous solution by adsorption onto novel polyelectrolyte film-coated nanofibrous silk fibroin non-wovens

NASA Astrophysics Data System (ADS)

Zhou, Weitao; Huang, Haitao; Du, Shan; Huo, Yingdong; He, Jianxin; Cui, Shizhong

2015-08-01

In this approach, polyelectrolyte film-coated nanofibrous silk fibroin (SF) nonwovens were prepared from the alternate deposition of positively charged polyethylenimine (PEI) and negatively charged SF using electrostatic layer-by-layer (LBL) self-assembled technology. The composite membranes were characterized by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectrometer. The SF-PEI multilayer-assembled nanofibers (less than five layers) were fine and uniform with the fiber diameter from 400 nm to 600 nm, and had very large surface area and high porosity (more than 70%). The amino groups of PEI were proved to be deposited onto SF nonwovens, which granted the coated nonwovens with potential applicability for copper ions adsorption. The PEI films coated SF substrate showed much higher copper ions adsorption capacity than that of ethanol treated SF nanofibers. Adding the number of PEI coated could enhance the Cu2+ adsorption capacity significantly. The maximum milligrams per gram of copper ions adsorbed reached 59.7 mg/g when the SF substrate was coated with 5 bilayers of SF-PEI. However, the copper ions adsorption capacity had no obvious change as the number of PEI continued to increase. These results suggest potential for PEL film-coated nanofibrous nonwovens as a new adsorbent for metal ions.

Assessment of airborne asbestos exposure during the servicing and handling of automobile asbestos-containing gaskets.

PubMed

Blake, Charles L; Dotson, G Scott; Harbison, Raymond D

2006-07-01

Five test sessions were conducted to assess asbestos exposure during the removal or installation of asbestos-containing gaskets on vehicles. All testing took place within an operative automotive repair facility involving passenger cars and a pickup truck ranging in vintage from late 1960s through 1970s. A professional mechanic performed all shop work including engine disassembly and reassembly, gasket manipulation and parts cleaning. Bulk sample analysis of removed gaskets through polarized light microscopy (PLM) revealed asbestos fiber concentrations ranging between 0 and 75%. Personal and area air samples were collected and analyzed using National Institute of Occupational Safety Health (NIOSH) methods 7400 [phase contrast microscopy (PCM)] and 7402 [transmission electron microscopy (TEM)]. Among all air samples collected, approximately 21% (n = 11) contained chrysotile fibers. The mean PCM and phase contrast microscopy equivalent (PCME) 8-h time weighted average (TWA) concentrations for these samples were 0.0031 fibers/cubic centimeters (f/cc) and 0.0017 f/cc, respectively. Based on these findings, automobile mechanics who worked with asbestos-containing gaskets may have been exposed to concentrations of airborne asbestos concentrations approximately 100 times lower than the current Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (PEL) of 0.1 f/cc.

Lymphocyte migration in the micro-channel of splenic sheathed capillaries in Chinese soft-shelled turtles, Pelodiscus sinensis.

PubMed

Zhang, Qian; Ullah, Shakeeb; Liu, Yi; Yang, Ping; Chen, Bing; Waqas, Yasir; Bao, Huijun; Hu, Lisi; Li, Quanfu; Chen, Qiusheng

2016-01-01

The structural characteristics of the splenic sheathed capillary were investigated using light microscopy and transmission electron microscopy (TEM). This study mainly focused on lymphocyte migration to the splenic white pulp via micro-channels in Chinese soft-shelled turtles, Pelodiscus sinensis. The results showed that the sheathed capillaries in the turtle spleen were high endothelial venule (HEV)-like vessels. These capillaries consist of micro-channels that facilitate lymphocyte migration to the splenic white pulp. The micro-channel is a dynamic structure comprising processes of endothelial cells, supporting cells, and ellipsoid-associated cells (EACs), which provides a microenvironment for lymphocyte migration. The pattern of lymphocyte migration in the micro-channel of the turtle spleen includes the following steps: (i) lymphocyte first adheres to the endothelium of the sheathed capillary, passes through the endothelial cells, and traverses through the basement membrane of the sheathed capillary; (ii) it then enters into the ellipsoid combined with supporting cells and EACs; and (iii) lymphocyte migrates from the ellipsoid to the periellipsoidal lymphatic sheath (PELS) via the micro-channel. This study provides morphological evidence for lymphocyte migration in the micro-channels of turtle spleens and also an insight into the mechanism of lymphocyte homing to the splenic white pulp of reptiles. Copyright © 2015 Elsevier Ltd. All rights reserved.

σ and κ mesons as broad dynamical resonances in one-meson-exchange model

NASA Astrophysics Data System (ADS)

Hong Xiem, Ngo Thi; Shinmura, Shoji

2014-09-01

The existences of broad scalar σ (600) and κ (700) mesons have been discussed intensively in the experimental and theoretical studies on ππ and πK scatterings. By using chiral perturbation model, J. Oller, A. Gómez and J. R. Peláez confirmed the existence of these mesons as dynamical resonances. In meson-exchange models, their existence has not been established yet. In this talk, using the quasi-potential of meson-exchange model and Lippmann-Schwinger equation, we determine the T and S-matrices, from which we could find the positions of poles in physical amplitudes in the complex E-plane. With the full treatment of meson-meson interactions (ππ - πK - πη - ηη and πK - ηK) , for the first time, the existence of the scalar σ (600) and κ (700) mesons are confirmed in one-meson-exchange model. There are two kinds of form factors in our model: the monopole and the Gaussian. Our recent results show that the poles σ and κ appear at around 410 - i 540 MeV and 650 - i 20 MeV for monopole form factors, respectively. For Gaussian form factors, the poles σ and κ, respectively, are at 360 - i 510 MeV and 649 - i 190 MeV.

Novel genetic factors involved in resistance to Bacillus thuringiensis in Plutella xylostella.

PubMed

Ayra-Pardo, C; Raymond, B; Gulzar, A; Rodríguez-Cabrera, L; Morán-Bertot, I; Crickmore, N; Wright, D J

2015-12-01

The widespread and sustainable exploitation of the entomopathogen Bacillus thuringiensis (Bt) in pest control is threatened by the evolution of resistance. Although resistance is often associated with loss of binding of the Bt toxins to the insect midgut cells, other factors have been implicated. Here we used suppressive subtractive hybridization and gene expression suppression to identify additional molecular components involved in Bt-resistance in Plutella xylostella. We isolated transcripts from genes that were differentially expressed in the midgut of larvae from a resistant population, following ingestion of a Bt kurstaki HD1 strain-based commercial formulation (DiPel), and compared with a genetically similar susceptible population. Quantitative real-time polymerase-chain reaction (RT-PCR) analysis confirmed the differential basal expression of a subset of these genes. Gene expression suppression of three of these genes (P. xylostella cyclin-dependent kinase 5 regulatory subunit associated protein 1-like 1, stromal cell-derived factor 2-like 1 and hatching enzyme-like 1) significantly increased the pathogenicity of HD1 to the resistant population. In an attempt to link the multitude of factors reportedly influencing resistance to Bt with the well-characterized loss of toxin binding, we also considered Bt-resistance models in P. xylostella and other insects. © 2015 The Royal Entomological Society.

Fusion of Kinect depth data with trifocal disparity estimation for near real-time high quality depth maps generation

NASA Astrophysics Data System (ADS)

Boisson, Guillaume; Kerbiriou, Paul; Drazic, Valter; Bureller, Olivier; Sabater, Neus; Schubert, Arno

2014-03-01

Generating depth maps along with video streams is valuable for Cinema and Television production. Thanks to the improvements of depth acquisition systems, the challenge of fusion between depth sensing and disparity estimation is widely investigated in computer vision. This paper presents a new framework for generating depth maps from a rig made of a professional camera with two satellite cameras and a Kinect device. A new disparity-based calibration method is proposed so that registered Kinect depth samples become perfectly consistent with disparities estimated between rectified views. Also, a new hierarchical fusion approach is proposed for combining on the flow depth sensing and disparity estimation in order to circumvent their respective weaknesses. Depth is determined by minimizing a global energy criterion that takes into account the matching reliability and the consistency with the Kinect input. Thus generated depth maps are relevant both in uniform and textured areas, without holes due to occlusions or structured light shadows. Our GPU implementation reaches 20fps for generating quarter-pel accurate HD720p depth maps along with main view, which is close to real-time performances for video applications. The estimated depth is high quality and suitable for 3D reconstruction or virtual view synthesis.

Multi-pollutant emissions from the burning of major agricultural residues in China and the related health-economic effects

NASA Astrophysics Data System (ADS)

Li, Chunlin; Hu, Yunjie; Zhang, Fei; Chen, Jianmin; Ma, Zhen; Ye, Xingnan; Yang, Xin; Wang, Lin; Tang, Xingfu; Zhang, Renhe; Mu, Mu; Wang, Guihua; Kan, Haidong; Wang, Xinming; Mellouki, Abdelwahid

2017-04-01

Multi-pollutants in smoke particulate matter (SPM) were identified and quantified for the biomass burning of five major agricultural residues (wheat, rice, corn, cotton, and soybean straw) in China by an aerosol chamber system combined with various measurement techniques. The primary emission factors (EFs) for PM1. 0 and PM2. 5 are 3.04-12.64 and 3.25-15.16 g kg-1. Organic carbon (OC), elemental carbon (EC), water-soluble inorganics (WSIs), water-soluble organic acids (WSOAs), water-soluble amine salts (WSAs), trace mineral elements (THMs), polycyclic aromatic hydrocarbons (PAHs), and phenols in smoke PM1. 0/PM2. 5 are 1.34-6.04/1.54-7.42, 0.58-2.08/0.61-2.18, 0.51-3.52/0.52-3.81, 0.13-0.64/0.14-0.77, (4.39-85.72/4.51-104.79) × 10-3, (11.8-51.1/14.0-131.6) × 10-3, (1.1-4.0/1.8-8.3) × 10-3, and (7.7-23.5/9.7-41.5) × 10-3 g kg-1, respectively. Black carbon (BC) mainly exists in PM1. 0; heavy-metal-bearing particles favour residing in the range of smoke PM1. 0-2. 5, which is also confirmed by individual particle analysis. With respect to the five scenarios of burning activities, the average emissions and overall propagation of uncertainties at the 95 % confidence interval (CI) of SPM from agricultural open burning in China in 2012 were estimated to be 1005.7 (-24.6, 33.7 %), 901.4 (-24.4, 33.5 %), 432.4 (-24.2, 33.5 %), 134.2 (-24., 34.0 %), 249.8 (-25.4, 34.9 %), 25.1 (-33.3, 41.4 %), 5.8 (-30.1, 38.5 %), 8.7 (-26.6, 35.6 %), 0.5 (-26.0, 34.9 %), and 2.7 (-26.1, 35.1 %) Gg for PM2. 5, PM1. 0, OC, EC, WSI, WSOA, WSA, THM, PAHs, and phenols , respectively. The emissions were further spatio-temporally characterized using a geographic information system (GIS) in different regions in the summer and autumn post-harvest periods. It was found that less than 25 % of the total emissions were released during the summer harvest, which was mainly contributed by the North Plain and the centre of China, especially Henan, Shandong, and Anhui, which are the top three provinces regarding smoke particle emissions. Flux concentrations of primarily emitted smoke PM2. 5 that were calculated using the box-model method based on five versions of emission inventories all exceed the carcinogenic-risk permissible exposure limits (PEL). The health impacts and health-related economic losses from the smoke PM2. 5 short-term exposure were assessed. The results show that China suffered from 7836 cases (95,% CI: 3232, 12362) of premature mortality and 7 267 237 cases (95 % CI: 2 961 487, 1 130 784) of chronic bronchitis in 2012, which led to losses of USD 8822.4 million (95 % CI: 3574.4, 13 034.2) or 0.1 % of the total GDP. We suggest that the percentage of open-burnt crop straw in the post-harvest period should be cut down by over 97 % to ensure a reduction in carcinogenicity risk, especially in the North Plain and the northeast, where the emissions should decrease at least by 94 % to meet the PEL. With such emission control, over 92 % of the mortality and morbidity attributed to agricultural fire smoke PM2. 5 can be avoided in China.

Seismicity pattern: an indicator of source region of volcanism at convergent plate margins

NASA Astrophysics Data System (ADS)

Špičák, Aleš; Hanuš, Václav; Vaněk, Jiří

2004-04-01

The results of detailed investigation into the geometry of distribution of earthquakes around and below the volcanoes Korovin, Cleveland, Makushin, Yake-Dake, Oshima, Lewotobi, Fuego, Sangay, Nisyros and Montagne Pelée at convergent plate margins are presented. The ISC hypocentral determinations for the period 1964-1999, based on data of global seismic network and relocated by Engdahl, van der Hilst and Buland, have been used. The aim of this study has been to contribute to the solution of the problem of location of source regions of primary magma for calc-alkaline volcanoes spatially and genetically related to the process of subduction. Several specific features of seismicity pattern were revealed in this context. (i) A clear occurrence of the intermediate-depth aseismic gap (IDAG) in the Wadati-Benioff zone (WBZ) below all investigated active volcanoes. We interpret this part of the subducted slab, which does not contain any teleseismically recorded earthquake with magnitude greater than 4.0, as a partially melted domain of oceanic lithosphere and as a possible source of primary magma for calc-alkaline volcanoes. (ii) A set of earthquakes in the shape of a seismically active column (SAC) seems to exists in the continental wedge below volcanoes Korovin, Makushin and Sangay. The seismically active columns probably reach from the Earth surface down to the aseismic gap in the Wadati-Benioff zone. This points to the possibility that the upper mantle overlying the subducted slab does not contain large melted domains, displays an intense fracturing and is not likely to represent the site of magma generation. (iii) In the continental wedge below the volcanoes Cleveland, Fuego, Nisyros, Yake-Dake, Oshima and Lewotobi, shallow seismicity occurs down to the depth of 50 km. The domain without any earthquakes between the shallow seismically active column and the aseismic gap in the Wadati-Benioff zone in the depth range of 50-100 km does not exclude the melting of the mantle also above the slab. (iv) Any earthquake does not exist in the lithospheric wedge below the volcano Montagne Pelée. The source of primary magma could be located in the subducted slab as well as in the overlying mantle wedge. (v) Frequent aftershock sequences accompanying stronger earthquakes in the seismically active columns indicate high fracturing of the wedge below active volcanoes. (vi) The elongated shape of clusters of epicentres of earthquakes of seismically active columns, as well as stable parameters of the available fault plane solutions, seem to reflect the existence of dominant deeply rooted fracture zones below volcanoes. These facts also favour the location of primary magma in the subducting slab rather than in the overlying wedge. We suppose that melts advancing from the slab toward the Earth surface may trigger the observed earthquakes in the continental wedge that is critically pre-stressed by the process of subduction. However, for definitive conclusions it will be necessary to explain the occurrence of earthquake clusters below some volcanoes and the lack of seismicity below others, taking into account the uncertainty of focal depth determination from global seismological data in some regions.

Essential Components of a Perimeter Air Monitoring Plan and Worker Protection Program at Sites Involving the Excavation of Naturally Occurring Asbestos (NOA) in California

NASA Astrophysics Data System (ADS)

Zdeb, T. F.

2012-12-01

Preparing a Perimeter Air Monitoring Plan that provides the essential information and methods of evaluation needed to assure that the health of the surrounding community is adequately protected and adapting currently existing Cal/OSHA regulations to be relevant to the protection of workers at sites involving the excavation of Naturally Occurring Asbestos (NOA) is oftentimes challenging in California. Current guidelines regarding what constitutes an effective air monitoring program are often lacking in details regarding what should be sampled and analyzed to characterize a site and what evaluation techniques should be applied to process the results of monitoring, and the current Cal/OSHA asbestos related regulations regarding worker protection are for the most part largely pertinent to the abatement of asbestos in buildings. An overview of the essential components of an effective Baseline and Perimeter Air Monitoring Plan will be presented that includes a brief discussion of the various asbestos types and fiber sizes that may need to be considered, possible approachs for evaluating temporal and spatial variability, review of selected site boundary target concentrations, and consideration of the potential for airborne dust and soil containing asbestos (and other contaminants) to migrate and accumulate offsite eventually contributing to "background creep" --the incremental increase of overall airborne asbestos concentrations in the areas surrounding the site due to the re-entrainment of asbestos from the settled dust and/or transported soil. In addition to the above, the current Cal/OSHA asbestos regulations related to worker protection will be briefly discussed with respect to their relevancy at NOA sites with an overview of the adaptations to the regulations that were developed as a result of some fairly lengthy discussions with representatives of Cal/OSHA. These adaptations include, among other things, defining how regulated areas (asbestos concentrations over 1%) and "provisionally regulated" areas (less than 1%) are established and treated, what variables need to be considered when attempting to complete a personal exposure assessment, Cal/OSHA Permissible Exposure Limits (PELs) versus site specific permissible exposure limits, allowable work practices, and the qualifications of personnel performing the sampling and analyses of data.

Mercury pollution from the artisanal mining in Yani gold district, Northern Bolivia

NASA Astrophysics Data System (ADS)

Alfonso, Pura; Freixas, Anna; Bascompta, Marc; María Aranibar, Ana; Villegas, Karla; María García-Noguero, Eva; Higueras, Pablo; Cielito Saraiva, Angela

2016-04-01

Artisanal gold mining is the main economic activity in the Yani district, Northern Bolivia. In this area abundant orogenic gold deposits constituted by quartz veins hosted in paleozoic turbiditic series that contain either free gold or associated with pyrite. Gold is recovered in processing plants by gravimetric methods using shaking tables in several communities of this district. Previously, miners ground the mineral in ball mills together with mercury. The present study aims to evaluate the effect of mercury used in the gold recovering process to the environment and human health in the Yani district. The assessment was based on the analysis of human hair, sediments and water from the river nearby the processing plant and drinking water from the fountain that supplies these communities. 47 samples of hair from miners and other people from the Yani and Señor de Mayo communities were obtained in 2014 and 52 samples in 2015. All were analysed to evaluate the mercury exposure in these places. The results from the 2014 sampling show a wide range of Hg concentration in hair, especially in Señor de Mayo, with values up to 136 μg/g THg. However, in 2015 among the 43 residents in Señor de Mayo, 29 (67%) exhibit concentrations higher than 2 μg/g THg, with an average value of 5.36 μg/g THg. On the other hand, in Yani only 40% have concentrations above 2 μg/g THg, with an average value of 2.34 μg/g THg. The content in Hg in most of the hair samples exhibit values above the tolerable limits established by the US Environmental Protection Agency (1 μg/g Hg) and the World Health Organisation (WHO, 2 μg/g Hg). These high Hg concentrations are found not only in miners but also in the other members of the community, in spite of low fish consumption in this area. Part of the hair was analysed before and after cleaning. Usually in the second case the content of Hg is reduced, but still show high Hg levels, then probably the atmosphere is polluted with Hg and population is exposed to Hg vapour. The average of Hg contents in hair from Señor de Mayo is double than in Yani. This can be explained because in the former the processing plant is located much closer to the community. The THg concentration in water from the river vary from 0.12 to 0.22 μg/g THg and from the drinking water display values around 0.22 μg/g THg, both below the tolerable limits indicated by the WHO. THg levels in sediments collected in river near the processing plant of Señor de Mayo and Yani show high Hg concentrations, 2.4 and 5.9 μg/g, respectively, which represent a serious environmental risk. Most of the obtained values of mercury concentration in hair indicate a high level of pollution. The miners of these areas should find out alternative methods for gold recovery. Acknowledgements: This research was financed by the Centre de Cooperació pel Desenvolupament projects 2014-O014 and 2015-O-022.

Human health and performance considerations for near earth asteroids (NEA)

NASA Astrophysics Data System (ADS)

Steinberg, Susan; Kundrot, Craig; Charles, John

2013-11-01

Humans are considered as a system in the design of any deep space exploration mission. The addition of many potential near asteroid (NEA) destinations to the existing multiple mission architecture for Lunar and Mars missions increases the complexity of human health and performance issues that are anticipated for exploration of space. We suggest that risks to human health and performance be analyzed in terms of the 4 major parameters related to multiple mission architecture: destination, duration, distance and vehicle design. Geological properties of the NEA will influence design of exploration tasks related to sample handling and containment, and extravehicular activity (EVA) capabilities including suit ports and tools. A robotic precursor mission that collects basic information on NEA surface properties would reduce uncertainty about these aspects of the mission as well as aid in mission architecture and exploration task design. Key mission parameters are strongly impacted by duration and distance. The most critical of these is deep-space radiation exposure without even the temporary shielding of a nearby large planetary body. The current space radiation permissible exposure limits (PEL) limits mission duration to 3-10 months depending on age, gender and stage of the solar cycle. Duration also impacts mission architectures including countermeasures for bone, muscle, and cardiovascular atrophy during continuous weightlessness; and behavioral and psychological issues resulting from isolation and confinement. Distance affects communications and limits abort and return options for a NEA mission. These factors are anticipated to have important effects on crew function and autonomous operations, as well as influence medical capability, supplies and training requirements of the crew. The design of a habitat volume that can maintain the physical and psychological health of the crew and support mission operations with limited intervention from earth will require an integrated research and development effort between NASA's Human Research Program (HRP), engineering and human factors groups. Packaging food to extend shelf life and waste management will be important components of vehicle subsystem design.

Development of Welding Fumes Health Index (WFHI) for Welding Workplace's Safety and Health Assessment.

PubMed

Hariri, Azian; Paiman, Nuur Azreen; Leman, Abdul Mutalib; Md Yusof, Mohammad Zainal

2014-08-01

This study aimed to develop an index that can rank welding workplace that associate well with possible health risk of welders. Welding Fumes Health Index (WFHI) were developed based on data from case studies conducted in Plant 1 and Plant 2. Personal sampling of welding fumes to assess the concentration of metal constituents along with series of lung function tests was conducted. Fifteen metal constituents were investigated in each case study. Index values were derived from aggregation analysis of metal constituent concentration while significant lung functions were recognized through statistical analysis in each plant. The results showed none of the metal constituent concentration was exceeding the permissible exposure limit (PEL) for all plants. However, statistical analysis showed significant mean differences of lung functions between welders and non-welders. The index was then applied to one of the welding industry (Plant 3) for verification purpose. The developed index showed its promising ability to rank welding workplace, according to the multiple constituent concentrations of welding fumes that associates well with lung functions of the investigated welders. There was possibility that some of the metal constituents were below the detection limit leading to '0' value of sub index, thus the multiplicative form of aggregation model was not suitable for analysis. On the other hand, maximum or minimum operator forms suffer from compensation issues and were not considered in this study.

Evidence that platelet-derived growth factor may be a novel endogenous pyrogen in the central nervous system.

PubMed

Pelá, I R; Ferreira, M E; Melo, M C; Silva, C A; Coelho, M M; Valenzuela, C F

2000-05-01

Platelet-derived growth factor (PDGF) exerts neurotrophic and neuromodulatory actions in the mammalian central nervous system (CNS). Like the cytokines, PDGF primarily signals through tyrosine phosphorylation-dependent pathways that activate multiple intracellular molecules including Janus family kinases. We previously showed that microinjection of PDGF-BB into the lateral ventricle induced a febrile response in rats that was reduced by pretreatment with Win 41662, a potent inhibitor of PDGF receptors (Pelá IR, Ferreira MES, Melo MCC, Silva CAA, and Valenzuela CF. Ann NY Acad Sci 856: 289-293, 1998). In this study, we further characterized the role of PDGF-BB in the febrile response in rats. Microinjection of PDGF-BB into the third ventricle produced a dose-dependent increase in colonic temperature that peaked 3-4 h postinjection. Win 41662 attenuated fever induced by intraperitoneal injection of bacterial lipopolysaccharide, suggesting that endogenous PDGF participates in the febrile response to this exogenous pyrogen. Importantly, febrile responses induced by tumor necrosis factor-alpha, interleukin-1beta, and interleukin-6 were unchanged by Win 41662. Both indomethacin and dexamethasone blocked the PDGF-BB-induced increase in colonic temperature, and, therefore, we postulate that PDGF-BB may act via prostaglandin- and/or inducible enzyme-dependent pathways. Thus our findings suggest that PDGF-BB is an endogenous CNS mediator of the febrile response in rats.

A novel technique using potassium permanganate and reflectance confocal microscopy to image biofilm extracellular polymeric matrix reveals non-eDNA networks in Pseudomonas aeruginosa biofilms

PubMed Central

Swearingen, Matthew C.; Mehta, Ajeet; Mehta, Amar; Nistico, Laura; Hill, Preston J.; Falzarano, Anthony R.; Wozniak, Daniel J.; Hall-Stoodley, Luanne; Stoodley, Paul

2015-01-01

Biofilms are etiologically important in the development of chronic medical and dental infections. The biofilm extracellular polymeric substance (EPS) determines biofilm structure and allows bacteria in biofilms to adapt to changes in mechanical loads such as fluid shear. However, EPS components are difficult to visualize microscopically because of their low density and molecular complexity. Here, we tested potassium permanganate, KMnO4, for use as a non-specific EPS contrast-enhancing stain using confocal laser scanning microscopy in reflectance mode. We demonstrate that KMnO4 reacted with EPS components of various strains of Pseudomonas, Staphylococcus and Streptococcus, yielding brown MnO2 precipitate deposition on the EPS, which was quantifiable using data from the laser reflection detector. Furthermore, the MnO2 signal could be quantified in combination with fluorescent nucleic acid staining. COMSTAT image analysis indicated that KMnO4 staining increased the estimated biovolume over that determined by nucleic acid staining alone for all strains tested, and revealed non-eDNA EPS networks in Pseudomonas aeruginosa biofilm. In vitro and in vivo testing indicated that KMnO4 reacted with poly-N-acetylglucosamine and Pseudomonas Pel polysaccharide, but did not react strongly with DNA or alginate. KMnO4 staining may have application as a research tool and for diagnostic potential for biofilms in clinical samples. PMID:26536894

Epidemiology of Epstein-Barr virus, cytomegalovirus, and Kaposi's sarcoma-associated herpesvirus infections in peripheral blood leukocytes revealed by a multiplex PCR assay.

PubMed

Nishiwaki, Morie; Fujimuro, Masahiro; Teishikata, Yasuhiro; Inoue, Hisanori; Sasajima, Hitoshi; Nakaso, Kazuhiro; Nakashima, Kenji; Sadanari, Hidetaka; Yamamoto, Tomohiro; Fujiwara, Yoshie; Ogawa, Naoki; Yokosawa, Hideyoshi

2006-12-01

A multiplex polymerase chain reaction (PCR) has been developed for the simultaneous detection of Epstein-Barr virus (EBV), cytomegalovirus (CMV), and Kaposi's sarcoma-associated herpesvirus (KSHV) in a clinical sample. Primers of multiplex PCR were designed to amplify specific regions of the EBV EBNA1, CMV IE2, and KSHV LANA genes. This multiplex PCR assay was found to have detection sensitivities of 1-10 copies of purified viral DNA cloned into the plasmid. To assess diagnostic and pre-clinical applications with this method, we utilized KSHV-positive primary effusion lymphoma (PEL) cells, EBV-positive Burkitt's lymphoma cells, CMV-infected fibroblast cells, and clinically prepared peripheral blood leukocytes (PBLs) that had been infected with viruses. We found that this multiplex PCR assay has high sensitivity and specificity for simultaneous detection of EBV, CMV, and KSHV genomes in a single amplification from a clinical material. Using this multiplex PCR assay, we investigated the prevalence of EBV, CMV, and KSHV in PBL samples from normal Japanese randomly selected. KSHV, EBV, and CMV genomes were detected in samples from 2 (0.2%), 377 (39.5%), and 27 (2.8%) of the 953 blood donors, respectively. Interestingly, both EBV and CMV genomes were detected in samples from all KSHV-positive donors. (c) 2006 Wiley-Liss, Inc.

The impacts of pyroclastic surges on buildings at the eruption of the Soufrière Hills volcano, Montserrat

NASA Astrophysics Data System (ADS)

Baxter, Peter J.; Boyle, Robin; Cole, Paul; Neri, Augusto; Spence, Robin; Zuccaro, Giulio

2005-04-01

We investigated the impacts on buildings of three pyroclastic surges that struck three separate villages on 25 June, 21 September and 26 December, 1997, during the course of the andesitic dome building eruption of the Soufrière Hills Volcano, Montserrat, which began on 18 July, 1995. A detailed analysis of the building damage of the 26 December event was used to compare the findings on the flow and behaviour of dilute pyroclastic density currents (PDCs) with the classical reports of PDCs from historical eruptions of similar size. The main characteristics of the PDC, as inferred from the building damage, were the lateral loading and directionality of the current; the impacts corresponded to the dynamic pressure of the PDC, with a relatively slow rate of rise and without the peak overpressure or a shock front associated with explosive blast; and the entrainment of missiles and ground materials which greatly added to the destructiveness of the PDC. The high temperature of the ash, causing the rapid ignition of furniture and other combustibles, was a major cause of damage even where the dynamic pressure was low at the periphery of the current. The vulnerability of buildings lay in the openings, mainly windows, which allowed the current to enter the building envelope, and in the flammable contents, as well as the lack of resistance to the intense heat and dynamic pressure of some types of vernacular building construction, such as wooden chattel houses, rubble masonry walls and galvanised steel-sheet roofs. Marked variability in the level of damage due to dynamic pressure (in a range 1-5 kPa, or more) was evident throughout most of the impact area, except for the zone of total loss, and this was attributable to the effects of topography and sheltering, and projectiles, and probably localised variations in current velocity and density. A marked velocity gradient existed from the outer part to the central axis of the PDC, where buildings and vegetation were razed to the ground. The gradient correlated with the impacts due to lateral loading and heat transfer, as well as the size of the projectiles, whilst the temperature of the ash in the undiluted PDC was probably uniform across the impact area. The main hazard characteristics of the PDCs were very consistent with those described by other authors in the classic eruptions of Pelée (1902), Lamington (1951) and St Helens (1980), despite differences in the eruptive styles and scales. We devised for the first time a building damage scale for dynamic pressure which can be used in research and in future volcanic emergencies for modelling PDCs and making informed judgements on their potential impacts.

Development of Welding Fumes Health Index (WFHI) for Welding Workplace’s Safety and Health Assessment

PubMed Central

HARIRI, Azian; PAIMAN, Nuur Azreen; LEMAN, Abdul Mutalib; MD. YUSOF, Mohammad Zainal

2014-01-01

Abstract Background This study aimed to develop an index that can rank welding workplace that associate well with possible health risk of welders. Methods Welding Fumes Health Index (WFHI) were developed based on data from case studies conducted in Plant 1 and Plant 2. Personal sampling of welding fumes to assess the concentration of metal constituents along with series of lung function tests was conducted. Fifteen metal constituents were investigated in each case study. Index values were derived from aggregation analysis of metal constituent concentration while significant lung functions were recognized through statistical analysis in each plant. Results The results showed none of the metal constituent concentration was exceeding the permissible exposure limit (PEL) for all plants. However, statistical analysis showed significant mean differences of lung functions between welders and non-welders. The index was then applied to one of the welding industry (Plant 3) for verification purpose. The developed index showed its promising ability to rank welding workplace, according to the multiple constituent concentrations of welding fumes that associates well with lung functions of the investigated welders. Conclusion There was possibility that some of the metal constituents were below the detection limit leading to ‘0’ value of sub index, thus the multiplicative form of aggregation model was not suitable for analysis. On the other hand, maximum or minimum operator forms suffer from compensation issues and were not considered in this study. PMID:25927034

Cloned Erwinia chrysanthemi out genes enable Escherichia coli to selectively secrete a diverse family of heterologous proteins to its milieu.

PubMed

He, S Y; Lindeberg, M; Chatterjee, A K; Collmer, A

1991-02-01

The out genes of the enterobacterial plant pathogen Erwinia chrysanthemi are responsible for the efficient extracellular secretion of multiple plant cell wall-degrading enzymes, including four isozymes of pectate lyase, exo-poly-alpha-D-galacturonosidase, pectin methylesterase, and cellulase. Out- mutants of Er. chrysanthemi are unable to export any of these proteins beyond the periplasm and are severely reduced in virulence. We have cloned out genes from Er. chrysanthemi in the stable, low-copy-number cosmid pCPP19 by complementing several transposon-induced mutations. The cloned out genes were clustered in a 12-kilobase chromosomal DNA region, complemented all existing out mutations in Er. chrysanthemi EC16, and enabled Escherichia coli strains to efficiently secrete the extracellular pectic enzymes produced from cloned Er. chrysanthemi genes, while retaining the periplasmic marker protein beta-lactamase. DNA sequencing of a 2.4-kilobase EcoRI fragment within the out cluster revealed four genes arranged colinearly and sharing substantial similarity with the Klebsiella pneumoniae genes pulH, pulI, pulJ, and pulK, which are necessary for pullulanase secretion. However, K. pneumoniae cells harboring the cloned Er. chrysanthemi pelE gene were unable to secrete the Erwinia pectate lyase. Furthermore, the Er. chrysanthemi Out system was unable to secrete an extracellular pectate lyase encoded by a gene from a closely related plant pathogen. Erwinia carotovora ssp. carotovora. The results suggest that these enterobacteria secrete polysaccharidases by a conserved mechanism whose protein-recognition capacities have diverged.

Regulatory RNAs and the HptB/RetS signalling pathways fine-tune Pseudomonas aeruginosa pathogenesis

PubMed Central

Bordi, Christophe; Lamy, Marie-Cécile; Ventre, Isabelle; Termine, Elise; Hachani, Abderrahman; Fillet, Sandy; Roche, Béatrice; Bleves, Sophie; Méjean, Vincent; Lazdunski, Andrée; Filloux, Alain

2010-01-01

Bacterial pathogenesis often depends on regulatory networks, two-component systems and small RNAs (sRNAs). In Pseudomonas aeruginosa, the RetS sensor pathway downregulates expression of two sRNAs, rsmY and rsmZ. Consequently, biofilm and the Type Six Secretion System (T6SS) are repressed, whereas the Type III Secretion System (T3SS) is activated. We show that the HptB signalling pathway controls biofilm and T3SS, and fine-tunes P. aeruginosa pathogenesis. We demonstrate that RetS and HptB intersect at the GacA response regulator, which directly controls sRNAs production. Importantly, RetS controls both sRNAs, whereas HptB exclusively regulates rsmY expression. We reveal that HptB signalling is a complex regulatory cascade. This cascade involves a response regulator, with an output domain belonging to the phosphatase 2C family, and likely an anti-anti-σ factor. This reveals that the initial input in the Gac system comes from several signalling pathways, and the final output is adjusted by a differential control on rsmY and rsmZ. This is exemplified by the RetS-dependent but HptB-independent control on T6SS. We also demonstrate a redundant action of the two sRNAs on T3SS gene expression, while the impact on pel gene expression is additive. These features underpin a novel mechanism in the fine-tuned regulation of gene expression. PMID:20398205

A chimeric protein composed of NuMA fused to the DNA binding domain of LANA is sufficient for the ori-P-dependent DNA replication

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

Ohsaki, Eriko; Ueda, Keiji, E-mail: kueda@virus.me

The Kaposi's sarcoma-associated herpesvirus (KSHV) genome is stably maintained in KSHV-infected PEL cell lines during cell division. We previously showed that accumulation of LANA in the nuclear matrix fraction could be important for the latent DNA replication, and that the functional significance of LANA should be its recruitment of ori-P to the nuclear matrix. Here, we investigated whether the forced localization of the LANA-DNA binding domain (DBD) to the nuclear matrix facilitated ori-P-containing plasmid replication. We demonstrated that chimeric proteins constructed by fusion of LANA DBD with the nuclear mitotic apparatus protein (NuMA), which is one of the components ofmore » the nuclear matrix, could bind with ori-P and enhance replication of an ori-P-containing plasmid, compared with that in the presence of DBD alone. These results further suggested that the ori-P recruitment to the nuclear matrix through the binding with DBD is important for latent viral DNA replication. - Highlights: •KSHV replication in latency depends on LANA localization to the nuclear matrix. •LANA DBD was fused with NuMA, a nuclear matrix protein, at the N- and C-terminus. •NuMA-DBD was in the nuclear matrix and supported the ori-P dependent replication. •LANA in the nuclear matrix should be important for the KSHV replication in latency.« less

A novel technique using potassium permanganate and reflectance confocal microscopy to image biofilm extracellular polymeric matrix reveals non-eDNA networks in Pseudomonas aeruginosa biofilms.

PubMed

Swearingen, Matthew C; Mehta, Ajeet; Mehta, Amar; Nistico, Laura; Hill, Preston J; Falzarano, Anthony R; Wozniak, Daniel J; Hall-Stoodley, Luanne; Stoodley, Paul

2016-02-01

Biofilms are etiologically important in the development of chronic medical and dental infections. The biofilm extracellular polymeric substance (EPS) determines biofilm structure and allows bacteria in biofilms to adapt to changes in mechanical loads such as fluid shear. However, EPS components are difficult to visualize microscopically because of their low density and molecular complexity. Here, we tested potassium permanganate, KMnO4, for use as a non-specific EPS contrast-enhancing stain using confocal laser scanning microscopy in reflectance mode. We demonstrate that KMnO4 reacted with EPS components of various strains of Pseudomonas, Staphylococcus and Streptococcus, yielding brown MnO2 precipitate deposition on the EPS, which was quantifiable using data from the laser reflection detector. Furthermore, the MnO2 signal could be quantified in combination with fluorescent nucleic acid staining. COMSTAT image analysis indicated that KMnO4 staining increased the estimated biovolume over that determined by nucleic acid staining alone for all strains tested, and revealed non-eDNA EPS networks in Pseudomonas aeruginosa biofilm. In vitro and in vivo testing indicated that KMnO4 reacted with poly-N-acetylglucosamine and Pseudomonas Pel polysaccharide, but did not react strongly with DNA or alginate. KMnO4 staining may have application as a research tool and for diagnostic potential for biofilms in clinical samples. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

KSHV-Mediated Angiogenesis in Tumor Progression

PubMed Central

Purushothaman, Pravinkumar; Uppal, Timsy; Sarkar, Roni; Verma, Subhash C.

2016-01-01

Human herpesvirus 8 (HHV-8), also known as Kaposi’s sarcoma-associated herpesvirus (KSHV), is a malignant human oncovirus belonging to the gamma herpesvirus family. HHV-8 is closely linked to the pathogenesis of Kaposi’s sarcoma (KS) and two other B-cell lymphoproliferative diseases: primary effusion lymphoma (PEL) and a plasmablastic variant of multicentric Castleman’s disease (MCD). KS is an invasive tumor of endothelial cells most commonly found in untreated HIV-AIDS or immuno-compromised individuals. KS tumors are highly vascularized and have abnormal, excessive neo-angiogenesis, inflammation, and proliferation of infected endothelial cells. KSHV directly induces angiogenesis in an autocrine and paracrine fashion through a complex interplay of various viral and cellular pro-angiogenic and inflammatory factors. KS is believed to originate due to a combination of KSHV’s efficient strategies for evading host immune systems and several pro-angiogenic and pro-inflammatory stimuli. In addition, KSHV infection of endothelial cells produces a wide array of viral oncoproteins with transforming capabilities that regulate multiple host-signaling pathways involved in the activation of angiogenesis. It is likely that the cellular-signaling pathways of angiogenesis and lymph-angiogenesis modulate the rate of tumorigenesis induction by KSHV. This review summarizes the current knowledge on regulating KSHV-mediated angiogenesis by integrating the findings reported thus far on the roles of host and viral genes in oncogenesis, recent developments in cell-culture/animal-model systems, and various anti-angiogenic therapies for treating KSHV-related lymphoproliferative disorders. PMID:27447661

A Phosphate Minimum in the Oxygen Minimum Zone (OMZ) off Peru

NASA Astrophysics Data System (ADS)

Paulmier, A.; Giraud, M.; Sudre, J.; Jonca, J.; Leon, V.; Moron, O.; Dewitte, B.; Lavik, G.; Grasse, P.; Frank, M.; Stramma, L.; Garcon, V.

2016-02-01

The Oxygen Minimum Zone (OMZ) off Peru is known to be associated with the advection of Equatorial SubSurface Waters (ESSW), rich in nutrients and poor in oxygen, through the Peru-Chile UnderCurrent (PCUC), but this circulation remains to be refined within the OMZ. During the Pelágico cruise in November-December 2010, measurements of phosphate revealed the presence of a phosphate minimum (Pmin) in various hydrographic stations, which could not be explained so far and could be associated with a specific water mass. This Pmin, localized at a relatively constant layer ( 20<220 m) and with a patchy distribution mainly between 10 and 16°S, is confirmed and characterized in details from the complementary hydrological data acquired during the German Meteor cruise M77 (Legs 3 and 4, January-February 2009). The significant Pmin present an intense minimum with a mean vertical phosphate decrease of 0.6 µM but highly variable between 0.1 and 2.2 µM. In average, these Pmin are associated with a predominant mixing of SubTropical Under- and Surface Waters (STUW and STSW: 20 and 40%, respectively) within ESSW ( 25%), complemented evenly by overlying (ESW, TSW: 8%) and underlying waters (AAIW, SPDW: 7%). The hypotheses and mechanisms leading to the Pmin formation in the OMZ are further explored and discussed, considering the physical regional contribution associated with various circulation pathways ventilating the OMZ and the local biogeochemical contribution including the potential diazotrophic activity.

Heterologous expression, refolding and functional characterization of two antifreeze proteins from Fragilariopsis cylindrus (Bacillariophyceae).

PubMed

Uhlig, Christiane; Kabisch, Johannes; Palm, Gottfried J; Valentin, Klaus; Schweder, Thomas; Krell, Andreas

2011-12-01

Antifreeze proteins (AFPs) provide protection for organisms subjected to the presence of ice crystals. The psychrophilic diatom Fragilariopsis cylindrus which is frequently found in polar sea ice carries a multitude of AFP isoforms. In this study we report the heterologous expression of two antifreeze protein isoforms from F. cylindrus in Escherichia coli. Refolding from inclusion bodies produced proteins functionally active with respect to crystal deformation, recrystallization inhibition and thermal hysteresis. We observed a reduction of activity in the presence of the pelB leader peptide in comparison with the GS-linked SUMO-tag. Activity was positively correlated to protein concentration and buffer salinity. Thermal hysteresis and crystal deformation habit suggest the affiliation of the proteins to the hyperactive group of AFPs. One isoform, carrying a signal peptide for secretion, produced a thermal hysteresis up to 1.53°C±0.53°C and ice crystals of hexagonal bipyramidal shape. The second isoform, which has a long preceding N-terminal sequence of unknown function, produced thermal hysteresis of up to 2.34°C±0.25°C. Ice crystals grew in form of a hexagonal column in presence of this protein. The different sequences preceding the ice binding domain point to distinct localizations of the proteins inside or outside the cell. We thus propose that AFPs have different functions in vivo, also reflected in their specific TH capability. Copyright © 2011 Elsevier Inc. All rights reserved.

A Comparison of "Total Dust" and Inhalable Personal Sampling for Beryllium Exposure

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

Carter, Colleen M.

2012-05-09

In 2009, the American Conference of Governmental Industrial Hygienists (ACGIH) reduced the Beryllium (Be) 8-hr Time Weighted Average Threshold Limit Value (TLV-TWA) from 2.0 μg/m 3 to 0.05 μg/m 3 with an inhalable 'I' designation in accordance with ACGIH's particle size-selective criterion for inhalable mass. Currently, per the Department of Energy (DOE) requirements, the Lawrence Livermore National Laboratory (LLNL) is following the Occupational Health and Safety Administration (OSHA) Permissible Exposure Limit (PEL) of 2.0 μg/m 3 as an 8-hr TWA, which is also the 2005 ACGIH TLV-TWA, and an Action Level (AL) of 0.2 μg/m 3 and sampling is performedmore » using the 37mm (total dust) sampling method. Since DOE is considering adopting the newer 2009 TLV guidelines, the goal of this study was to determine if the current method of sampling using the 37mm (total dust) sampler would produce results that are comparable to what would be measured using the IOM (inhalable) sampler specific to the application of high energy explosive work at LLNL's remote experimental test facility at Site 300. Side-by-side personal sampling using the two samplers was performed over an approximately two-week period during chamber re-entry and cleanup procedures following detonation of an explosive assembly containing Beryllium (Be). The average ratio of personal sampling results for the IOM (inhalable) vs. 37-mm (total dust) sampler was 1.1:1 with a P-value of 0.62, indicating that there was no statistically significant difference in the performance of the two samplers. Therefore, for the type of activity monitored during this study, the 37-mm sampling cassette would be considered a suitable alternative to the IOM sampler for collecting inhalable particulate matter, which is important given the many practical and economic advantages that it presents. However, similar comparison studies would be necessary for this conclusion to be applied to other types of activities, where earlier studies have shown that the IOM sampler tends to collect higher concentrations of Be compared to the 37-mm cassette, which could complicate compliance with what is already an extremely low exposure limit.« less

The Development and Testing of a Prototype Mini-Baghouse to Control the Release of Respirable Crystalline Silica from Sand Movers

PubMed Central

Alexander, Barbara M.; Esswein, Eric J.; Gressel, Michael G.; Kratzer, Jerry L.; Feng, H. Amy; King, Bradley; Miller, Arthur L.; Cauda, Emanuele

2016-01-01

Inhalation of respirable crystalline silica (RCS) is a significant risk to worker health during well completions operations (which include hydraulic fracturing) at conventional and unconventional oil and gas extraction sites. RCS is generated by pneumatic transfer of quartz-containing sand during hydraulic fracturing operations. National Institute for Occupational Safety and Health (NIOSH) researchers identified concentrations of RCS at hydraulic fracturing sites that exceed 10 times the Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (PEL) and up to 50 times the NIOSH Recommended Exposure Limit (REL). NIOSH research identified at least seven point sources of dust release at contemporary oil and gas extraction sites where RCS aerosols were generated. NIOSH researchers recommend the use of engineering controls wherever they can be implemented to limit the RCS released. A control developed to address one of the largest sources of RCS aerosol generation is the NIOSH mini-baghouse assembly, mounted on the thief hatches on top of the sand mover. This manuscript details the results of a trial of the NIOSH mini-baghouse at a sand mine in Arkansas, November 18 – 21, 2013. During the trial, area air samples were collected at 12 locations on and around a sand mover with and without the mini-baghouse control installed. Analytical results for respirable dust and RCS indicate the use of the mini-baghouse effectively reduced both respirable dust and RCS downwind of the thief hatches. Reduction of airborne respirable dust ranged from 85% to 98%; reductions in airborne RCS ranged from 79% to 99%. A bulk sample of dust collected by the baghouse assembly showed the likely presence of freshly fractured quartz, a particularly hazardous form of RCS. Planned future design enhancements will increase the performance and durability of the mini-baghouse, including an improved bag clamp mechanism and upgraded filter fabric with a modified air-to-cloth ratio. Future trials are planned to determine additional respirable dust and RCS concentration reductions achieved through these design changes. PMID:27003622

Analysis of the plant bos1 mutant highlights necrosis as an efficient defence mechanism during D. dadantii/Arabidospis thaliana interaction.

PubMed

Kraepiel, Yvan; Pédron, Jacques; Patrit, Oriane; Simond-Côte, Elizabeth; Hermand, Victor; Van Gijsegem, Frédérique

2011-04-21

Dickeya dadantii is a broad host range phytopathogenic bacterium provoking soft rot disease on many plants including Arabidopsis. We showed that, after D. dadantii infection, the expression of the Arabidopsis BOS1 gene was specifically induced by the production of the bacterial PelB/C pectinases able to degrade pectin. This prompted us to analyze the interaction between the bos1 mutant and D. dadantii. The phenotype of the infected bos1 mutant is complex. Indeed, maceration symptoms occurred more rapidly in the bos1 mutant than in the wild type parent but at a later stage of infection, a necrosis developed around the inoculation site that provoked a halt in the progression of the maceration. This necrosis became systemic and spread throughout the whole plant, a phenotype reminiscent of that observed in some lesion mimic mutants. In accordance with the progression of maceration symptoms, bacterial population began to grow more rapidly in the bos1 mutant than in the wild type plant but, when necrosis appeared in the bos1 mutant, a reduction in bacterial population was observed. From the plant side, this complex interaction between D. dadantii and its host includes an early plant defence response that comprises reactive oxygen species (ROS) production accompanied by the reinforcement of the plant cell wall by protein cross-linking. At later timepoints, another plant defence is raised by the death of the plant cells surrounding the inoculation site. This plant cell death appears to constitute an efficient defence mechanism induced by D. dadantii during Arabidopsis infection.

Cloned Erwinia chrysanthemi out genes enable Escherichia coli to selectively secrete a diverse family of heterologous proteins to its milieu.

PubMed Central

He, S Y; Lindeberg, M; Chatterjee, A K; Collmer, A

1991-01-01

The out genes of the enterobacterial plant pathogen Erwinia chrysanthemi are responsible for the efficient extracellular secretion of multiple plant cell wall-degrading enzymes, including four isozymes of pectate lyase, exo-poly-alpha-D-galacturonosidase, pectin methylesterase, and cellulase. Out- mutants of Er. chrysanthemi are unable to export any of these proteins beyond the periplasm and are severely reduced in virulence. We have cloned out genes from Er. chrysanthemi in the stable, low-copy-number cosmid pCPP19 by complementing several transposon-induced mutations. The cloned out genes were clustered in a 12-kilobase chromosomal DNA region, complemented all existing out mutations in Er. chrysanthemi EC16, and enabled Escherichia coli strains to efficiently secrete the extracellular pectic enzymes produced from cloned Er. chrysanthemi genes, while retaining the periplasmic marker protein beta-lactamase. DNA sequencing of a 2.4-kilobase EcoRI fragment within the out cluster revealed four genes arranged colinearly and sharing substantial similarity with the Klebsiella pneumoniae genes pulH, pulI, pulJ, and pulK, which are necessary for pullulanase secretion. However, K. pneumoniae cells harboring the cloned Er. chrysanthemi pelE gene were unable to secrete the Erwinia pectate lyase. Furthermore, the Er. chrysanthemi Out system was unable to secrete an extracellular pectate lyase encoded by a gene from a closely related plant pathogen. Erwinia carotovora ssp. carotovora. The results suggest that these enterobacteria secrete polysaccharidases by a conserved mechanism whose protein-recognition capacities have diverged. Images PMID:1992458

Purification and Characterization of Biofilm-Associated EPS Exopolysaccharides from ESKAPE Organisms and Other Pathogens.

PubMed

Bales, Patrick M; Renke, Emilija Miljkovic; May, Sarah L; Shen, Yang; Nelson, Daniel C

2013-01-01

In bacterial biofilms, high molecular weight, secreted exopolysaccharides can serve as a scaffold to which additional carbohydrates, proteins, lipids, and nucleic acids adhere, forming the matrix of the developing biofilm. Here we report methods to extract and purify high molecular weight (>15 kDa) exopolysaccharides from biofilms of eight human pathogens, including species of Staphylcococcus, Klebsiella, Acinetobacter, Pseudomonas, and a toxigenic strain of Escherichia coli O157:H7. Glycosyl composition analysis indicated a high total mannose content across all strains with P. aeruginosa and A. baumannii exopolysaccharides comprised of 80-90% mannose, K. pneumoniae and S. epidermidis strains containing 40-50% mannose, and E. coli with ∼10% mannose. Galactose and glucose were also present in all eight strains, usually as the second and third most abundant carbohydrates. N-acetyl-glucosamine and galacturonic acid were found in 6 of 8 strains, while arabinose, fucose, rhamnose, and xylose were found in 5 of 8 strains. For linkage analysis, 33 distinct residue-linkage combinations were detected with the most abundant being mannose-linked moieties, in line with the composition analysis. The exopolysaccharides of two P. aeruginosa strains analyzed were consistent with the Psl carbohydrate, but not Pel or alginate. The S. epidermidis strain had a composition rich in mannose and glucose, which is consistent with the previously described slime associated antigen (SAA) and the extracellular slime substance (ESS), respectively, but no polysaccharide intracellular adhesion (PIA) was detected. The high molecular weight exopolysaccharides from E. coli, K. pneumoniae, and A. baumannii appear to be novel, based on composition and/or ratio analysis of carbohydrates.

Multiple plasmid-borne virulence genes of Clavibacter michiganensis ssp. capsici critical for disease development in pepper.

PubMed

Hwang, In Sun; Oh, Eom-Ji; Kim, Donghyuk; Oh, Chang-Sik

2018-02-01

Clavibacter michiganensis ssp. capsici is a Gram-positive plant-pathogenic bacterium causing bacterial canker disease in pepper. Virulence genes and mechanisms of C. michiganensis ssp. capsici in pepper have not yet been studied. To identify virulence genes of C. michiganensis ssp. capsici, comparative genome analyses with C. michiganensis ssp. capsici and its related C. michiganensis subspecies, and functional analysis of its putative virulence genes during infection were performed. The C. michiganensis ssp. capsici type strain PF008 carries one chromosome (3.056 Mb) and two plasmids (39 kb pCM1 Cmc and 145 kb pCM2 Cmc ). The genome analyses showed that this bacterium lacks a chromosomal pathogenicity island and celA gene that are important for disease development by C. michiganensis ssp. michiganensis in tomato, but carries most putative virulence genes in both plasmids. Virulence of pCM1 Cmc -cured C. michiganensis ssp. capsici was greatly reduced compared with the wild-type strain in pepper. The complementation analysis with pCM1 Cmc -located putative virulence genes showed that at least five genes, chpE, chpG, ppaA1, ppaB1 and pelA1, encoding serine proteases or pectate lyase contribute to disease development in pepper. In conclusion, C. michiganensis ssp. capsici has a unique genome structure, and its multiple plasmid-borne genes play critical roles in virulence in pepper, either separately or together. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

The Relationship between Elemental Carbon and Diesel Particulate Matter in Underground Metal/Nonmetal Mines in the United States and Coal Mines in Australia

PubMed Central

Noll, James; Gilles, Stewart; Wu, Hsin Wei; Rubinstein, Elaine

2015-01-01

In the United States, total carbon (TC) is used as a surrogate for determining diesel particulate matter (DPM) compliance exposures in underground metal/nonmetal mines. Since TC can be affected by interferences and elemental carbon (EC) is not, one method used to estimate the TC concentration is to multiply the EC concentration from the personal sample by a conversion factor to avoid the influence of potential interferences. Since there is no accepted single conversion factor for all metal/nonmetal mines, one is determined every time an exposure sample is taken by collecting an area sample that represents the TC/EC ratio in the miner's breathing zone and is away from potential interferences. As an alternative to this procedure, this article investigates the relationship between TC and EC from DPM samples to determine if a single conversion factor can be used for all metal/nonmetal mines. In addition, this article also investigates how well EC represents DPM concentrations in Australian coal mines since the recommended exposure limit for DPM in Australia is an EC value. When TC was predicted from EC values using a single conversion factor of 1.27 in 14 US metal/nonmetal mines, 95% of the predicted values were within 18% of the measured value, even at the permissible exposure limit (PEL) concentration of 160 μg/m3 TC. A strong correlation between TC and EC was also found in nine underground coal mines in Australia. PMID:25380085

Hot pressing in conduit faults during lava dome extrusion: Insights from Mount St. Helens 2004-2008

NASA Astrophysics Data System (ADS)

Ryan, Amy G.; Friedlander, Elizabeth A.; Russell, James K.; Heap, Michael J.; Kennedy, Lori A.

2018-01-01

Rhyodacitic volcanoes such as Mount St. Helens (MSH), Soufrière Hills, Mount Unzen and Mount Pelée erupt spines mantled by layers of magma-derived cataclasite and fault gouge. MSH produced seven lava spines from 2004-2008 composed of low-porosity, compositionally uniform, crystalline dacite. Dome extrusion was attended by continuous 'drumbeat' seismicity, derived from faulting along the conduit margin at 0.5-1 km depth, and evidenced by the enveloping gouge layers. We describe the properties of the gouge-derived fault rocks, including laboratory measurements of porosity and permeability. The gouge varies from unconsolidated powder to lithified low-porosity low-permeability fault rocks. We reconstruct the subsurface ascent of the MSH magma using published field observations and create a model that reconciles the diverse properties of the gouge with conditions in the conduit during ascent (i.e. velocity, temperature). We show lithification of the gouge to be driven by 'hot pressing' processes, wherein the combination of elevated temperature, confining pressure and dwell-time cause densification and solid-state sintering of the comminuted, crystal-rich (glass-poor) gouge. The degree of gouge lithification corresponds with residence time in the conduit such that well-lithified materials reflect extended times in the subsurface due to slower ascent rates. With this insight, we suggest that gouge competence can be used as a first-order estimate of lava ascent rates. Furthermore we posit gouge lithification, which reduces porosity and permeability, inhibits volcanic outgassing thereby increasing the potential for explosive events at spine-producing volcanoes.

Tectonic context of moderate to large historical earthquakes in the Lesser Antilles and mechanical coupling with volcanoes

NASA Astrophysics Data System (ADS)

Feuillet, Nathalie; Beauducel, FrançOis; Tapponnier, Paul

2011-10-01

The oblique convergence between North American and Caribbean plates is accommodated in a bookshelf faulting manner by active, oblique-normal faults in the northern part of the Lesser Antilles arc. In the last 20 years, two M > 6 earthquakes occurred along a large, arc parallel, en echelon fault system, the 16 March 1985 in Redonda and 21 November 2004 in Les Saintes. A better understanding of active faulting in this region permit us to review the location and magnitude of historical earthquakes by using a regional seismic attenuation law. Several others moderate earthquakes may have occurred along the en echelon fault system implying a strong seismic hazard along the arc. These faults control the effusion of volcanic products and some earthquakes seem to be correlated in time with volcanic unrest. Shallow earthquakes on intraplate faults induced normal stress and pressure changes around neighboring volcano and may have triggered volcanic activity. The Redonda earthquake could have initiated the 1995 eruption of Montserrat's Soufrière Hills by compressing its plumbing system. Conversely, pressure changes under the volcano increased Coulomb stress changes and brought some faults closer to failure, promoting seismicity. We also discuss the magnitude of the largest 11 January 1839 and 8 February 1843 megathrust interplate earthquakes. We calculate that they have increased the stress on some overriding intraplate faults and the extensional strain beneath several volcanoes. This may explain an increase of volcanic and seismic activity in the second half of the 19th century culminating with the devastating, 1902 Mount Pelée eruption.

Temperature-stress resistance and tolerance along a latitudinal cline in North American Arabidopsis lyrata.

PubMed

Wos, Guillaume; Willi, Yvonne

2015-01-01

The study of latitudinal gradients can yield important insights into adaptation to temperature stress. Two strategies are available: resistance by limiting damage, or tolerance by reducing the fitness consequences of damage. Here we studied latitudinal variation in resistance and tolerance to frost and heat and tested the prediction of a trade-off between the two strategies and their costliness. We raised plants of replicate maternal seed families from eight populations of North American Arabidopsis lyrata collected along a latitudinal gradient in climate chambers and exposed them repeatedly to either frost or heat stress, while a set of control plants grew under standard conditions. When control plants reached maximum rosette size, leaf samples were exposed to frost and heat stress, and electrolyte leakage (PEL) was measured and treated as an estimate of resistance. Difference in maximum rosette size between stressed and control plants was used as an estimate of tolerance. Northern populations were more frost resistant, and less heat resistant and less heat tolerant, but-unexpectedly-they were also less frost tolerant. Negative genetic correlations between resistance and tolerance to the same and different thermal stress were generally not significant, indicating only weak trade-offs. However, tolerance to frost was consistently accompanied by small size under control conditions, which may explain the non-adaptive latitudinal pattern for frost tolerance. Our results suggest that adaptation to frost and heat is not constrained by trade-offs between them. But the cost of frost tolerance in terms of plant size reduction may be important for the limits of species distributions and climate niches.

Generation rate of carbon monoxide from CO2 arc welding.

PubMed

Ojima, Jun

2013-01-01

CO poisoning has been a serious industrial hazard in Japanese workplaces. Although incomplete combustion is the major cause of CO generation, there is a risk of CO poisoning during some welding operations. The aim of the present study was to evaluate the generation rate of CO from CO2 arc welding under controlled laboratory conditions and estimate the ventilation requirements for the prevention of CO poisoning. Bead on plate welding was carried out with an automatic welding robot on a rolled steel base metal under several conditions. The concentration of emitted CO from the welding was measured by a real-time CO monitor in a well-ventilated laboratory that was free from ambient CO contamination. The generation rate of CO was obtained from the three measurements-the flow rate of the welding exhaust gas, CO concentration in the exhaust gas and the arcing time. Then the ventilation requirement to prevent CO poisoning was calculated. The generation rate of CO was found to be 386-883 ml/min with a solid wire and 331-1,293 ml/min with a flux cored wire respectively. It was found that the CO concentration in a room would be maintained theoretically below the OSHA PEL (50 ppm) providing the ventilation rate in the room was 6.6-25.9 m3/min. The actual ventilation requirement was then estimated to be 6.6-259 m3/min considering incomplete mixing. In order to prevent CO poisoning, some countermeasures against gaseous emission as well as welding fumes should be taken eagerly.

Integrative assessment of sediment quality in lower basin affected by former mining in Brazil.

PubMed

Bonnail, Estefanía; Buruaem, Lucas M; Morais, Lucas G; Araujo, Giuliana S; Abessa, Denis M S; Sarmiento, Aguasanta M; Ángel DelValls, T

2017-06-13

The Ribeira de Iguape River (Southeast Brazil) is metal contaminated by mining activities. Despite it has been cataloged as "in via of restoration" by the literature, this basin is still a sink of pollution in some segments of the fluvial system. This study aimed to assess the sediment quality in the lower part of the RIR basin. The employed approach was based on biological responses of the freshwater clam Corbicula fluminea after 7-day exposure bioassays using as the reference site the Perequê Ecological Park. Toxic responses (burial activity and lethality) and biochemical biomarkers (GST, GR, GPx, LPO, MTs, AChE and DNA damage) were evaluated and then integrated with metal bioavailability and chemical concentrations to address the sediment quality in the area through the weight-of-evidence approach. A multivariate analysis identified linkages between biological responses and contamination. Results pointed that, despite being below the benchmarks of the US Environmental Protection Agency, there is slight metal contamination in the lower part of the basin which induces oxidative stress in C. fluminea; other toxic responses were sometimes attributed to As and Cr bioaccumulation. The sediment quality values (TEL-PEL values in mg/kg) were calculated for the current study for As (0.63-1.31), Cr (3.5-11.05), Cs (1.0-1.17), Cu (6.32-7.32), Ni (6.78-7.46), Ti (42.0-215), V (1.77-8.00). By comparison with other international guidelines, the sediment quality of the lower basin of the Vale de Ribeira does not identify a significant environmental risk.

Time Series Radar Observations of a Growing Lava Dome

NASA Astrophysics Data System (ADS)

Wadge, G.; Macfarlane, D. G.; Odbert, H. M.; James, M. R.; Hole, J. K.; Ryan, G.; Bass, V.; de Angelis, S.; Pinkerton, H.; Robertson, D. A.; Loughlin, S. C.

2007-12-01

Exogenous growth of Peléean lava domes occurs by addition of lava from a central summit vent and mass wasting on the flanks as rockfalls and pyroclastic flows, forming an apron of talus. We observed this process at the Soufrière Hills Volcano, Montserrat between 30 March and 10 April 2006 using a ground-based imaging mm-wave radar, AVTIS, to measure the shape of the dome surface.From a time series of range and intensity measurements at a distance of six kilometres we measured the topographic evolution of the lava dome. The locus of talus deposition moved to the southeast with time and the talus surface grew upwards on average at about 2 metres per day. The AVTIS measurements show an acceleration in lava extrusion rate on 5 April, with a 2-day lag in the equivalent rockfall seismicity record. We account for the budget of lava addition and dispersal during the eleven days of measurements using: AVTIS range measurements to measure the talus growth (7.2 Mm3, 67%), AVTIS range and intensity measurements to measure the summit lava growth (1.7 Mm3, 16%), and rockfall seismicity and visual observations to measure the pyroclastic flow deposits (1.8 Mm3, 17%). This gives an overall dense rock equivalent extrusion rate of about 9.7 m3s-1. These figures demonstrate how efficient non-explosive lava dome growth can be in generating large volumes of primary clastic deposits, and how this process could also reduce the propensity for large hazardous pyroclastic flows. andrews.ac.uk/~mmwave/mmwave/avtis.shtml

Mass Independent Fractionation of Cadmium Isotopes During Thermal Ionization

NASA Astrophysics Data System (ADS)

Abouchami, W.; Galer, S. J.; Feldmann, H.; Schmitt, A. D.

2008-12-01

We have previously reported that Cd isotopes exhibit anomalous, non-mass dependent fractionation of odd versus even isotopes when measured by TIMS using silica gel-phosphoric acid activator. The deviation from mass dependent fractionation (MDF) on the odd masses 111 and 113 varies by fractions of a per-cent between runs. The effects cannot be explained by isobaric interferences, but seem, instead, to reflect mass independent fractionation (MIF) of Cd isotopes, much like that recently documented for Hg isotopes in natural systems (Bergquist and Blum, 2007). The absence of comparable Cd isotope anomalies in the ICP torch, and during extreme in-vacuo volatilization of Cd metal (Wombacher et al., 2004) conclusively implicates the silica gel activator in the process. So far, MIF has been documented for Cd, Zn and Pb isotopes when measured using the silica gel technique (Thirlwall, 2000; Schmitt et al., 2006; Manhes and Göpel, 2007). These MIF effects on Cd isotopes might perhaps be related to the non-mass dependence of nuclear volume with mass number, as described by Bigeleisen (1996) - also known as the "nuclear field shift". The MIF caused by the nuclear field shift results is a departure from MDF broadly characterized by a odd-even staggering with mass number. These effects have been quantified by Schauble (2007) who showed that the magnitude of the non-mass dependence for Hg and Tl isotopes lies in the ppm range for some simple reactions. Such MIF effects would appear, overall, far too small to account for our data, which require MIF offsets on the odd masses 111 and 113 approaching a per-cent. Moreover, an in-depth examination along the lines of Fujii et al. (2006) predicts tell-tale offsets for the even-even isotope pairs 114Cd/112Cd and 116Cd/112Cd as well, based upon the theory and the respective nuclear radii, but such accompanying offsets are unequivocally absent in our data. The odd-even isotope effects seen in our runs using silica gel activator are better explained by appealing to the nuclear spin (and magnetic moment) of odd nuclei alone. The "magnetic isotope effect" is a consequence of hyperfine coupling, in which an electron interacts with a nucleus of non-zero magnetic moment - i.e. one that has an odd number of nucleons (Turro, 1983; Buchachenko, 1995, 2001). This is purely a kinetic phenomenon in which the life-time, and thus the outcome, of reaction transition states is altered by the hyperfine splitting present in atoms with odd nuclei. The mechanism by which silica gel activator enhances the thermal ionization of elements such as Cd, Pb and Zn has been outlined by Kessinger and Delmore (2002). The first step involves the in-situ reduction of Cd2+ ions to Cd metal in the molten silica gel-phosphoric acid glass. It is most likely in this step - whereby two electrons are added - that a suitably long-lived transition state exists, during which the magnetic isotope effect enhances (or inhibits) reduction of masses 111 and 113 to metal species compared to those of even isotopes of Cd. The resulting "odd" and "even" populations of Cd-metal in the molten silica gel then cannot be related simply in terms of MDF. Overall, the magnetic isotope effect provides the best explanation of the MIF effects observed for Pb, Cd and Zn during thermal ionization with silica gel activator, and, probably, why the measured fractionation is always biased towards light isotopes.

RsmV a small non-coding regulatory RNA in Pseudomonas aeruginosa that sequesters RsmA and RsmF from target mRNAs.

PubMed

Janssen, Kayley H; Diaz, Manisha R; Gode, Cindy J; Wolfgang, Matthew C; Yahr, Timothy L

2018-06-04

The Gram-negative opportunistic pathogen Pseudomonas aeruginosa has distinct genetic programs that favor either acute or chronic virulence gene expression. Acute virulence is associated with twitching and swimming motility, expression of a type III secretion system (T3SS), and the absence of alginate, Psl, or Pel polysaccharide production. Traits associated with chronic infection include growth as a biofilm, reduced motility, and expression of a type VI secretion system (T6SS). The Rsm post-transcriptional regulatory system plays important roles in the inverse control of phenotypes associated with acute and chronic virulence. RsmA and RsmF are RNA-binding proteins that interact with target mRNAs to control gene expression at the post-transcriptional level. Previous work found that RsmA activity is controlled by at least three small, non-coding regulatory RNAs (RsmW, RsmY, and RsmZ). In this study, we took an in-silico approach to identify additional sRNAs that might function in the sequestration of RsmA and/or RsmF and identified RsmV, a 192 nt transcript with four predicted RsmA/RsmF consensus binding sites. RsmV is capable of sequestering RsmA and RsmF in vivo to activate translation of tssA1 , a component of the T6SS, and to inhibit T3SS gene expression. Each of the predicted RsmA/RsmF consensus binding sites contribute to RsmV activity. Electrophoretic mobility shifts assays show that RsmF binds RsmV with >10-fold higher affinity than RsmY and RsmZ. Gene expression studies revealed that the temporal expression pattern of RsmV differs from RsmW, RsmY, and RsmZ. These findings suggest that each sRNA may play distinct roles in controlling RsmA and RsmF activity. IMPORTANCE The CsrA/RsmA family of RNA-binding proteins play important roles in post-transcriptional control of gene expression. The activity of CsrA/RsmA proteins is controlled by small non-coding RNAs that function as decoys to sequester CsrA/RsmA from target mRNAs. Pseudomonas aeruginosa has two CsrA family proteins (RsmA and RsmF) and at least four sequestering sRNAs (RsmV [identified in this study], RsmW, RsmY, RsmZ) that control RsmA/RsmF activity. RsmY and RsmZ are the primary sRNAs that sequester RsmA/RsmF, and RsmV and RsmW appear to play smaller roles. Differences in the temporal expression and absolute levels of the sRNAs and in their binding affinities for RsmA/RsmF may provide a mechanism of fine-tuning the output of the Rsm system in response to environmental cues. Copyright © 2018 American Society for Microbiology.

The toxicity of benzene and its metabolism and molecular pathology in human risk assessment.

PubMed Central

Yardley-Jones, A; Anderson, D; Parke, D V

1991-01-01

Benzene, a common industrial chemical and a component of gasoline, is radiomimetic and exposure may lead progressively to aplastic anaemia, leukaemia, and multiple myeloma. Although benzene has been shown to cause many types of genetic damage, it has consistently been classified as a non-mutagen in the Ames test, possibly because of the inadequacy of the S9 microsomal activation system. The metabolism of benzene is complex, yielding glucuronide and sulphate conjugates of phenol, quinol, and catechol, L-phenylmercapturic acid, and muconaldehyde and trans, trans-muconic acid by ring scission. Quinol is oxidised to p-benzoquinone, which binds to vital cellular components or undergoes redox cycling to generate oxygen radicals; muconaldehyde, like p-benzoquinone, is toxic through depletion of intracellular glutathione. Exposure to benzene may also induce the microsomal mixed function oxidase, cytochrome P450 IIE1, which is probably responsible for the oxygenation of benzene, but also has a propensity to generate oxygen radicals. The radiomimetic nature of benzene and its ability to induce different sites of neoplasia indicate that formation of oxygen radicals is a major cause of benzene toxicity, which involves multiple mechanisms including synergism between arylating and glutathione-depleting reactive metabolites and oxygen radicals. The occupational exposure limit in the United Kingdom (MEL) and the United States (PEL) was 10 ppm based on the association of benzene exposure with aplastic anaemia, but recently was lowered to 5 ppm and 1 ppm respectively, reflecting a concern for the risk of neoplasia. The American Conference of Governmental Industrial Hygienists (ACGIH) has even more recently recommended that, as benzene is considered an A1 carcinogen, the threshold limit value (TLV) should be decreased to 0.1 ppm. Only one study in man, based on nine cases of benzene associated fatal neoplasia, has been considered suitable for risk assessment. Recent re-evaluation of these data indicated that past assessments may have overestimated the risk, and different authors have considered that lifetime exposure to benzene at 1 ppm would result in an excess of leukaemia deaths of 9.5 to 1.0 per 1000. Although in this study, deaths at low levels of benzene exposure were associated with multiple myeloma and a long latency period, instead of leukaemia, which might justify further lowering of the exposure limit, the risk assessment model has been found to be non-significant for response at low levels of exposure. The paucity of data for man, the complexity of the metabolic activation of benzene, the interactive and synergistic mechanisms of benzene toxicity and carcinogenicity, the different disease endpoints (aplastic anaemia, leukaemia, and multiple myeloma), and different individual susceptibilities, all indicate that in such a complex scenario, regulators should proceed with caution before making further changes to the exposure limit for this chemical. PMID:1854646

A review of historical exposures to asbestos among skilled craftsmen (1940-2006).

PubMed

Williams, Pamela R D; Phelka, Amanda D; Paustenbach, Dennis J

2007-01-01

This article provides a review and synthesis of the published and selected unpublished literature on historical asbestos exposures among skilled craftsmen in various nonshipyard and shipyard settings. The specific crafts evaluated were insulators, pipefitters, boilermakers, masons, welders, sheet-metal workers, millwrights, electricians, carpenters, painters, laborers, maintenance workers, and abatement workers. Over 50 documents were identified and summarized. Sufficient information was available to quantitatively characterize historical asbestos exposures for the most highly exposed workers (insulators), even though data were lacking for some job tasks or time periods. Average airborne fiber concentrations collected for the duration of the task and/or the entire work shift were found to range from about 2 to 10 fibers per cubic centimeter (cm3 or cc) during activities performed by insulators in various nonshipyard settings from the late 1960s and early 1970s. Higher exposure levels were observed for this craft during the 1940s to 1950s, when dust counts were converted from millions of particles per cubic foot (mppcf) to units of fibers per cubic centimeter (fibers/cc) using a 1:6 conversion factor. Similar tasks performed in U.S. shipyards yielded average fiber concentrations about two-fold greater, likely due to inadequate ventilation and confined work environments; however, excessively high exposure levels were reported in some British Naval shipyards due to the spraying of asbestos. Improved industrial hygiene practices initiated in the early to mid-1970s were found to reduce average fiber concentrations for insulator tasks approximately two- to five-fold. For most other crafts, average fiber concentrations were found to typically range from <0.01 to 1 fibers/cc (depending on the task or time period), with higher concentrations observed during the use of powered tools, the mixing or sanding of drywall cement, and the cleanup of asbestos insulation or lagging materials. The available evidence suggests that although many historical measurements exceeded the current OSHA 8-h time-weighted average (TWA) permissible exposure limit (PEL) of 0.1 fibers/cc, average fiber concentrations generally did not exceed historical occupational exposure limits in place at the time, except perhaps during ripout activities or the spraying of asbestos in enclosed spaces or onboard ships. Additionally, reported fiber concentrations may not have represented daily or actual human exposures to asbestos, since few samples were collected beyond specific short-term tasks and workers sometimes wore respiratory protective equipment. The available data were not sufficient to determine whether the airborne fiber concentrations represented serpentine or amphibole asbestos fibers, which would have a pronounced impact on the potential health hazards posed by the asbestos. Despite a number of limitations associated with the available air sampling data, the information should provide guidance for reconstructing asbestos exposures for different crafts in specific occupational settings where asbestos was present during the 1940 to 2006 time period.

Bmcystatin, a cysteine proteinase inhibitor characterized from the tick Boophilus microplus

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

Lima, Cassia A.; Sasaki, Sergio D.; Tanaka, Aparecida S.

2006-08-18

The bovine tick Rhipicephalus (Boophilus) microplus is a blood-sucking animal, which is responsible for Babesia spp and Anaplasma marginale transmission for cattle. From a B. microplus fat body cDNA library, 465 selected clones were sequenced randomly and resulted in 60 Contigs. An open reading frame (ORF) contains 98 amino acids named Bmcystatin, due to 70% amino acid identity to a classical type 1 cystatin from Ixodes scapularis tick (GenBank Accession No. DQ066227). The Bmcystatin amino acid sequence analysis showed two cysteine residues, theoretical pI of 5.92 and M{sub r} of 11kDa. Bmcystatin gene was cloned in pET 26b vector andmore » the protein expressed using bacteria Escherichia coli BL21 SI. Recombinant Bmcystatin (rBmcystatin) purified by affinity chromatography on Ni-NTA-agarose column and ionic exchange chromatography on HiTrap Q column presented molecular mass of 11kDa, by SDS-PAGE and the N-terminal amino acid sequenced revealed unprocessed N-terminal containing part of pelB signal sequence. Purified rBmcystatin showed to be a C1 cysteine peptidase inhibitor with K{sub i} value of 0.1 and 0.6nM for human cathepsin L and VTDCE (vitellin degrading cysteine endopeptidase), respectively. The rBmcystatin expression analyzed by semi-quantitative RT-PCR confirmed the amplification of a specific DNA sequence (294bp) in the fat body and ovary cDNA preparation. On the other hand, a protein band was detected in the fat body, ovary, and the salivary gland extracts using anti-Bmcystatin antibody by Western blot. The present results suggest a possible role of Bmcystatin in the ovary, even though the gene was cloned from the fat body, which could be another site of this protein synthesis.« less

Bmcystatin, a cysteine proteinase inhibitor characterized from the tick Boophilus microplus.

PubMed

Lima, Cassia A; Sasaki, Sergio D; Tanaka, Aparecida S

2006-08-18

The bovine tick Rhipicephalus (Boophilus) microplus is a blood-sucking animal, which is responsible for Babesia spp and Anaplasma marginale transmission for cattle. From a B. microplus fat body cDNA library, 465 selected clones were sequenced randomly and resulted in 60 Contigs. An open reading frame (ORF) contains 98 amino acids named Bmcystatin, due to 70% amino acid identity to a classical type 1 cystatin from Ixodes scapularis tick (GenBank Accession No. ). The Bmcystatin amino acid sequence analysis showed two cysteine residues, theoretical pI of 5.92 and M(r) of 11 kDa. Bmcystatin gene was cloned in pET 26b vector and the protein expressed using bacteria Escherichia coli BL21 SI. Recombinant Bmcystatin (rBmcystatin) purified by affinity chromatography on Ni-NTA-agarose column and ionic exchange chromatography on HiTrap Q column presented molecular mass of 11 kDa, by SDS-PAGE and the N-terminal amino acid sequenced revealed unprocessed N-terminal containing part of pelB signal sequence. Purified rBmcystatin showed to be a C1 cysteine peptidase inhibitor with K(i) value of 0.1 and 0.6 nM for human cathepsin L and VTDCE (vitellin degrading cysteine endopeptidase), respectively. The rBmcystatin expression analyzed by semi-quantitative RT-PCR confirmed the amplification of a specific DNA sequence (294 bp) in the fat body and ovary cDNA preparation. On the other hand, a protein band was detected in the fat body, ovary, and the salivary gland extracts using anti-Bmcystatin antibody by Western blot. The present results suggest a possible role of Bmcystatin in the ovary, even though the gene was cloned from the fat body, which could be another site of this protein synthesis.

Directional emissivity and reflectance: dependence on emergence angle

NASA Astrophysics Data System (ADS)

Maturilli, Alessandro; Helbert, Jörn

2017-04-01

Dependence of laboratory measured emissivity spectra from the emergence angle is a subject that still needs a lot of investigations to be fully understood. Most of the previous work is based on reflectance measurements in the VIS-NIR spectral region and on emissivity measurements of flat, solid surfaces (mainly metals), which are not directly applicable to the analysis of remote sensing data. Small bodies in particular (c.f. asteroids Itokawa and 1999JU3, the respective targets of JAXA Hayabusa and Hayabusa 2 missions) have a very irregular surface; hence the spectra from those rough surfaces are difficult to compare with laboratory spectra, where the observing geometry is always close to "nadir". At the Planetary Emissivity Laboratory (PEL) of the German Aerospace Center (DLR) we have set-up a series of spectral measurements to investigate this problem in the 1 - 16 µm spectral region. We measured the emissivity for two asteroid analog materials (meteorite Millbillillie and a synthetic enstatite) in vacuum and under purged air, at surface temperature of 100°C, for emergence angles of 0°, 5°, 10°, 20°, 30°, 40°, 50°, and 60°. Emissivity of a serpentinite slab, already used as calibration target for the MARA instrument on Hayabusa 2 MASCOT lander, and for the Thermal Infrared Imager (TIR) spectrometer on Hayabusa 2 orbiter was measured under the same conditions. Additionally a second basalt slab was measured. Both slabs were not measured at 5° inclination. Complementary reflectance measurements of the four samples were taken. For all the samples measured, we found that for calibrated emissivity, significant variations from values obtained at nadir (0° emergence angle) appear only for emergence angles ≥ 40°. Reflectance measurements confirmed this finding, showing the same trend of variations.

Comprehensive QTL mapping survey dissects the complex fruit texture physiology in apple (Malus x domestica Borkh.).

PubMed

Longhi, Sara; Moretto, Marco; Viola, Roberto; Velasco, Riccardo; Costa, Fabrizio

2012-02-01

Fruit ripening is a complex physiological process in plants whereby cell wall programmed changes occur mainly to promote seed dispersal. Cell wall modification also directly regulates the textural properties, a fundamental aspect of fruit quality. In this study, two full-sib populations of apple, with 'Fuji' as the common maternal parent, crossed with 'Delearly' and 'Pink Lady', were used to understand the control of fruit texture by QTL mapping and in silico gene mining. Texture was dissected with a novel high resolution phenomics strategy, simultaneously profiling both mechanical and acoustic fruit texture components. In 'Fuji × Delearly' nine linkage groups were associated with QTLs accounting from 15.6% to 49% of the total variance, and a highly significant QTL cluster for both textural components was mapped on chromosome 10 and co-located with Md-PG1, a polygalacturonase gene that, in apple, is known to be involved in cell wall metabolism processes. In addition, other candidate genes related to Md-NOR and Md-RIN transcription factors, Md-Pel (pectate lyase), and Md-ACS1 were mapped within statistical intervals. In 'Fuji × Pink Lady', a smaller set of linkage groups associated with the QTLs identified for fruit texture (15.9-34.6% variance) was observed. The analysis of the phenotypic variance over a two-dimensional PCA plot highlighted a transgressive segregation for this progeny, revealing two QTL sets distinctively related to both mechanical and acoustic texture components. The mining of the apple genome allowed the discovery of the gene inventory underlying each QTL, and functional profile assessment unravelled specific gene expression patterns of these candidate genes.

Bipartite Topology of Treponema pallidum Repeat Proteins C/D and I

PubMed Central

Anand, Arvind; LeDoyt, Morgan; Karanian, Carson; Luthra, Amit; Koszelak-Rosenblum, Mary; Malkowski, Michael G.; Puthenveetil, Robbins; Vinogradova, Olga; Radolf, Justin D.

2015-01-01

We previously identified Treponema pallidum repeat proteins TprC/D, TprF, and TprI as candidate outer membrane proteins (OMPs) and subsequently demonstrated that TprC is not only a rare OMP but also forms trimers and has porin activity. We also reported that TprC contains N- and C-terminal domains (TprCN and TprCC) orthologous to regions in the major outer sheath protein (MOSPN and MOSPC) of Treponema denticola and that TprCC is solely responsible for β-barrel formation, trimerization, and porin function by the full-length protein. Herein, we show that TprI also possesses bipartite architecture, trimeric structure, and porin function and that the MOSPC-like domains of native TprC and TprI are surface-exposed in T. pallidum, whereas their MOSPN-like domains are tethered within the periplasm. TprF, which does not contain a MOSPC-like domain, lacks amphiphilicity and porin activity, adopts an extended inflexible structure, and, in T. pallidum, is tightly bound to the protoplasmic cylinder. By thermal denaturation, the MOSPN and MOSPC-like domains of TprC and TprI are highly thermostable, endowing the full-length proteins with impressive conformational stability. When expressed in Escherichia coli with PelB signal sequences, TprC and TprI localize to the outer membrane, adopting bipartite topologies, whereas TprF is periplasmic. We propose that the MOSPN-like domains enhance the structural integrity of the cell envelope by anchoring the β-barrels within the periplasm. In addition to being bona fide T. pallidum rare outer membrane proteins, TprC/D and TprI represent a new class of dual function, bipartite bacterial OMP. PMID:25805501

High-intensity focused ultrasound for ex vivo kidney tissue ablation: influence of generator power and pulse duration.

PubMed

Häcker, Axel; Köhrmann, Kai Uwe; Knoll, Thomas; Langbein, Sigrun; Steidler, Annette; Kraut, Oliver; Marlinghaus, Ernst; Alken, Peter; Michel, Maurice Stephan

2004-11-01

The therapeutic application of noninvasive tissue ablation by high-intensity focused ultrasound (HIFU) requires precise physical definition of the focal size and determination of control parameters. The objective of this study was to measure the extent of ex-vivo porcine kidney tissue ablation at variable generator parameters and to identify parameters to control lesion size. The ultrasound waves generated by a cylindrical piezoceramic element (1.04 MHz) were focused at a depth of 100 mm using a parabolic reflector (diameter 100 mm). A needle hydrophone was used to measure the field distribution of the sound pressure. The morphology and extent of tissue necrosis were examined at generator powers of up to 400 W (P(el)) and single pulse durations of as long as 8 seconds. The two-dimensional field distribution resulted in an approximately ellipsoidal focus of 32 x 4 mm (-6 dB). A sharp demarcation between coagulation necrosis and intact tissue was observed. Lesion size was controlled by both the variation of generator power and the pulse duration. At a constant pulse duration of 2 seconds, a generator power of 100 W remained below the threshold doses for inducing a reproducible lesion. An increase in power to as high as 400 W induced lesions with average dimensions of as much as 11.2 x 3 mm. At constant total energy (generator power x pulse duration), lesion size increased at higher generator power. This ultrasound generator can induce defined and reproducible necrosis in ex-vivo kidney tissue. Lesion size can be controlled by adjusting the generator power and pulse duration. Generator power, in particular, turned out to be a suitable control parameter for obtaining a lesion of a defined size.

Hypersensitivity pneumonitis due to metal working fluids: Sporadic or under reported?

PubMed

Gupta, Amit; Rosenman, Kenneth D

2006-06-01

Occupational exposure to metal working fluids (MWF) is common with over 1.2 million workers in the United States involved in machine finishing, machine tooling, and other metalworking operations. MWF is a known cause of hypersensitivity pneumonitis (HP). Recent reports of outbreaks of hypersensitivity HP secondary to exposure to MWF are reported. Cases were identified through the Occupational Disease surveillance system in the State of Michigan and from referrals for evaluation to the Division of Occupational and Environmental Medicine at Michigan State University (MSU). Each patient underwent a clinical examination including an occupational history, lung function studies, radiographic imaging, and in some cases lung biopsies. Following the diagnosis of definite HP, an industrial hygiene investigation was carried out, which included a plant walk-through, and review of the "Injury and Illness" log. Air monitoring and microbial sampling results were reviewed. As part of Michigan's mandatory surveillance system for occupational illnesses, seven cases of suspected HP were identified in 2003-2004 from three facilities manufacturing automobile parts in Michigan. Each plant used semi-synthetic MWFs, and conducted a MWF management program including biocide additions. Two facilities had recently changed the MWF before the cases arose. Growth of mycobacteria was found in these two MWFs. Breathing zone samples for particulates of two employees in plant A (two cases) ranged from 0.48 to 0.56 mg/m3. In plant B (four cases), two employees' sampling results ranged from 0.10 to 0.14 mg/m3. No air sampling data were available from plant C. Hypersensitivity pneumonitis due to exposure to MWFs is under-recognized by health care providers, and current surveillance systems are inadequate to provide a true estimate of its occurrence. HP arose from environments with exposures well below the Occupational Safety and Health Administration (OSHA) permissible exposure limit (PEL) for MWF, and in one case from exposures well below the National Institute of Occupational Safety and Health (NIOSH) recommended exposure limit (REL). The sporadic nature of reports of HP in relationship to MWF probably represents a combination of workplace changes that cause the disease and inadequate recognition and reporting of the disease when it does occur. Physician awareness of HP secondary to MWF and an effective medical surveillance program are necessary to better understanding the epidemiology and prevention of this disease.

ARID3B: a Novel Regulator of the Kaposi's Sarcoma-Associated Herpesvirus Lytic Cycle

PubMed Central

Wood, Jennifer J.; Boyne, James R.; Paulus, Christina; Jackson, Brian R.; Nevels, Michael M.

2016-01-01

ABSTRACT Kaposi's sarcoma-associated herpesvirus (KSHV) is the causative agent of commonly fatal malignancies of immunocompromised individuals, including primary effusion lymphoma (PEL) and Kaposi's sarcoma (KS). A hallmark of all herpesviruses is their biphasic life cycle—viral latency and the productive lytic cycle—and it is well established that reactivation of the KSHV lytic cycle is associated with KS pathogenesis. Therefore, a thorough appreciation of the mechanisms that govern reactivation is required to better understand disease progression. The viral protein replication and transcription activator (RTA) is the KSHV lytic switch protein due to its ability to drive the expression of various lytic genes, leading to reactivation of the entire lytic cycle. While the mechanisms for activating lytic gene expression have received much attention, how RTA impacts cellular function is less well understood. To address this, we developed a cell line with doxycycline-inducible RTA expression and applied stable isotope labeling of amino acids in cell culture (SILAC)-based quantitative proteomics. Using this methodology, we have identified a novel cellular protein (AT-rich interacting domain containing 3B [ARID3B]) whose expression was enhanced by RTA and that relocalized to replication compartments upon lytic reactivation. We also show that small interfering RNA (siRNA) knockdown or overexpression of ARID3B led to an enhancement or inhibition of lytic reactivation, respectively. Furthermore, DNA affinity and chromatin immunoprecipitation assays demonstrated that ARID3B specifically interacts with A/T-rich elements in the KSHV origin of lytic replication (oriLyt), and this was dependent on lytic cycle reactivation. Therefore, we have identified a novel cellular protein whose expression is enhanced by KSHV RTA with the ability to inhibit KSHV reactivation. IMPORTANCE Kaposi's sarcoma-associated herpesvirus (KSHV) is the causative agent of fatal malignancies of immunocompromised individuals, including Kaposi's sarcoma (KS). Herpesviruses are able to establish a latent infection, in which they escape immune detection by restricting viral gene expression. Importantly, however, reactivation of productive viral replication (the lytic cycle) is necessary for the pathogenesis of KS. Therefore, it is important that we comprehensively understand the mechanisms that govern lytic reactivation, to better understand disease progression. In this study, we have identified a novel cellular protein (AT-rich interacting domain protein 3B [ARID3B]) that we show is able to temper lytic reactivation. We showed that the master lytic switch protein, RTA, enhanced ARID3B levels, which then interacted with viral DNA in a lytic cycle-dependent manner. Therefore, we have added a new factor to the list of cellular proteins that regulate the KSHV lytic cycle, which has implications for our understanding of KSHV biology. PMID:27512077

What factors control the superficial lava dome explosivity?

NASA Astrophysics Data System (ADS)

Boudon, Georges; Balcone-Boissard, Hélène; Villemant, Benoit; Morgan, Daniel J.

2015-04-01

Dome-forming eruption is a frequent eruptive style; lava domes result from intermittent, slow extrusion of viscous lava. Most dome-forming eruptions produce highly microcrystallized and highly- to almost totally-degassed magmas which have a low explosive potential. During lava dome growth, recurrent collapses of unstable parts are the main destructive process of the lava dome, generating concentrated pyroclastic density currents (C-PDC) channelized in valleys. These C-PDC have a high, but localized, damage potential that largely depends on the collapsed volume. Sometimes, a dilute ash cloud surge develops at the top of the concentrated flow with an increased destructive effect because it may overflow ridges and affect larger areas. In some cases, large lava dome collapses can induce a depressurization of the magma within the conduit, leading to vulcanian explosions. By contrast, violent, laterally directed, explosions may occur at the base of a growing lava dome: this activity generates dilute and turbulent, highly-destructive, pyroclastic density currents (D-PDC), with a high velocity and propagation poorly dependent on the topography. Numerous studies on lava dome behaviors exist, but the triggering of lava dome explosions is poorly understood. Here, seven dome-forming eruptions are investigated: in the Lesser Antilles arc: Montagne Pelée, Martinique (1902-1905, 1929-1932 and 650 y. BP eruptions), Soufrière Hills, Montserrat; in Guatemala, Santiaguito (1929 eruption); in La Chaîne des Puys, France (Puy de Dome and Puy Chopine eruptions). We propose a new model of superficial lava-dome explosivity based upon a textural and geochemical study (vesicularity, microcrystallinity, cristobalite distribution, residual water contents, crystal transit times) of clasts produced by these key eruptions. Superficial explosion of a growing lava dome may be promoted through porosity reduction caused by both vesicle flattening due to gas escape and syn-eruptive cristobalite precipitation. Both processes generate an impermeable and rigid carapace allowing overpressurisation of the inner parts of the lava dome by the rapid input of vesiculated magma batches. The thickness of the cristobalite-rich carapace is an inverse function of the external lava dome surface area. Thus the probability of a superficial lava dome explosion inversely depends on its size; explosive activity more likely occurs at the onset of the lava dome extrusion in agreement with observations. We evidence a two-step process in magma ascent with edification of the lava dome that may be accompanied by a rapid ascent of an undegassed batch of magma some days prior the explosive activity. This new result is of interest for the whole volcanological community and for risk management.

Space Life Sciences at NASA: Spaceflight Health Policy and Standards

NASA Technical Reports Server (NTRS)

Davis, Jeffrey R.; House, Nancy G.

2006-01-01

In January 2005, the President proposed a new initiative, the Vision for Space Exploration. To accomplish the goals within the vision for space exploration, physicians and researchers at Johnson Space Center are establishing spaceflight health standards. These standards include fitness for duty criteria (FFD), permissible exposure limits (PELs), and permissible outcome limits (POLs). POLs delineate an acceptable maximum decrement or change in a physiological or behavioral parameter, as the result of exposure to the space environment. For example cardiovascular fitness for duty standards might be a measurable clinical parameter minimum that allows successful performance of all required duties. An example of a permissible exposure limit for radiation might be the quantifiable limit of exposure over a given length of time (e.g. life time radiation exposure). An example of a permissible outcome limit might be the length of microgravity exposure that would minimize bone loss. The purpose of spaceflight health standards is to promote operational and vehicle design requirements, aid in medical decision making during space missions, and guide the development of countermeasures. Standards will be based on scientific and clinical evidence including research findings, lessons learned from previous space missions, studies conducted in space analog environments, current standards of medical practices, risk management data, and expert recommendations. To focus the research community on the needs for exploration missions, NASA has developed the Bioastronautics Roadmap. The Bioastronautics Roadmap, NASA's approach to identification of risks to human space flight, revised baseline was released in February 2005. This document was reviewed by the Institute of Medicine in November 2004 and the final report was received in October 2005. The roadmap defines the most important research and operational needs that will be used to set policy, standards (define acceptable risk), and implement an overall Risk Management and Analysis process. Currently NASA is drafting spaceflight health standards for neurosensory alterations, space radiation exposure, behavioral health, muscle atrophy, cardiovascular fitness, immunological compromise, bone demineralization, and nutrition.

Malignant lymphomas (ML) and HIV infection in Tanzania.

PubMed

Mwakigonja, Amos R; Kaaya, Ephata E; Mgaya, Edward M

2008-06-10

HIV infection is reported to be associated with some malignant lymphomas (ML) so called AIDS-related lymphomas (ARL), with an aggressive behavior and poor prognosis. The ML frequency, pathogenicity, clinical patterns and possible association with AIDS in Tanzania, are not well documented impeding the development of preventive and therapeutic strategies. Sections of 176 archival formalin-fixed paraffin-embedded biopsies of ML patients at Muhimbili National Hospital (MNH)/Muhimbili University of Health and Allied Sciences (MUHAS), Tanzania from 1996-2001 were stained for hematoxylin and eosin and selected (70) cases for expression of pan-leucocytic (CD45), B-cell (CD20), T-cell (CD3), Hodgkin/RS cell (CD30), histiocyte (CD68) and proliferation (Ki-67) antigen markers. Corresponding clinical records were also evaluated. Available sera from 38 ML patients were screened (ELISA) for HIV antibodies. The proportion of ML out of all diagnosed tumors at MNH during the 6 year period was 4.2% (176/4200) comprising 77.84% non-Hodgkin (NHL) including 19.32% Burkitt's (BL) and 22.16% Hodgkin's disease (HD). The ML tumors frequency increased from 0.42% (1997) to 0.70% (2001) and 23.7% of tested sera from these patients were HIV positive. The mean age for all ML was 30, age-range 3-91 and peak age was 1-20 years. The male:female ratio was 1.8:1. Supra-diaphragmatic presentation was commonest and histological sub-types were mostly aggressive B-cell lymphomas however, no clear cases of primary effusion lymphoma (PEL) and primary central nervous system lymphoma (PCNSL) were diagnosed. Malignant lymphomas apparently, increased significantly among diagnosed tumors at MNH between 1996 and 2001, predominantly among the young, HIV infected and AIDS patients. The frequent aggressive clinical and histological presentation as well as the dominant B-immunophenotype and the HIV serology indicate a pathogenic association with AIDS. Therefore, routine HIV screening of all malignant lymphoma patients at MNH is necessary to enable comprehensive ARL diagnosis and formulation of preventive and therapeutic protocols.

Complete Sequencing of pNDM-HK Encoding NDM-1 Carbapenemase from a Multidrug-Resistant Escherichia coli Strain Isolated in Hong Kong

PubMed Central

Ho, Pak Leung; Lo, Wai U.; Yeung, Man Kiu; Lin, Chi Ho; Chow, Kin Hung; Ang, Irene; Tong, Amy Hin Yan; Bao, Jessie Yun-Juan; Lok, Si; Lo, Janice Yee Chi

2011-01-01

Background The emergence of plasmid-mediated carbapenemases, such as NDM-1 in Enterobacteriaceae is a major public health issue. Since they mediate resistance to virtually all β-lactam antibiotics and there is often co-resistance to other antibiotic classes, the therapeutic options for infections caused by these organisms are very limited. Methodology We characterized the first NDM-1 producing E. coli isolate recovered in Hong Kong. The plasmid encoding the metallo-β-lactamase gene was sequenced. Principal Findings The plasmid, pNDM-HK readily transferred to E. coli J53 at high frequencies. It belongs to the broad host range IncL/M incompatibility group and is 88803 bp in size. Sequence alignment showed that pNDM-HK has a 55 kb backbone which shared 97% homology with pEL60 originating from the plant pathogen, Erwina amylovora in Lebanon and a 28.9 kb variable region. The plasmid backbone includes the mucAB genes mediating ultraviolet light resistance. The 28.9 kb region has a composite transposon-like structure which includes intact or truncated genes associated with resistance to β-lactams (bla TEM-1, bla NDM-1, Δbla DHA-1), aminoglycosides (aacC2, armA), sulphonamides (sul1) and macrolides (mel, mph2). It also harbors the following mobile elements: IS26, ISCR1, tnpU, tnpAcp2, tnpD, ΔtnpATn1 and insL. Certain blocks within the 28.9 kb variable region had homology with the corresponding sequences in the widely disseminated plasmids, pCTX-M3, pMUR050 and pKP048 originating from bacteria in Poland in 1996, in Spain in 2002 and in China in 2006, respectively. Significance The genetic support of NDM-1 gene suggests that it has evolved through complex pathways. The association with broad host range plasmid and multiple mobile genetic elements explain its observed horizontal mobility in multiple bacterial taxa. PMID:21445317

Lava dome growth and mass wasting measured by a time series of ground-based radar and seismicity observations

NASA Astrophysics Data System (ADS)

Wadge, G.; Macfarlane, D. G.; Odbert, H. M.; James, M. R.; Hole, J. K.; Ryan, G.; Bass, V.; de Angelis, S.; Pinkerton, H.; Robertson, D. A.; Loughlin, S. C.

2008-08-01

Exogenous growth of Peléean lava domes involves the addition of lava from a central summit vent and mass wasting on the flanks as rockfalls and pyroclastic flows. These processes were investigated at the Soufrière Hills Volcano, Montserrat, between 30 March and 10 April 2006, using a ground-based imaging millimeter-wave radar, AVTIS, to measure the shape of the dome and talus surface and rockfall seismicity combined with camera observations to infer pyroclastic flow deposit volumes. The topographic evolution of the lava dome was recorded in a time series of radar range and intensity measurements from a distance of 6 km, recording a southeastward shift in the locus of talus deposition with time, and an average height increase for the talus surface of about 2 m a day. The AVTIS measurements show an acceleration in lava extrusion rate on 5 April, with a 2-day lag in the equivalent change in the rockfall seismicity record. The dense rock equivalent volumetric budget of lava added and dispersed, including the respective proportions of the total for each component, was calculated using: (1) AVTIS range and intensity measurements of the change in summit lava (˜1.5 × 106 m3, 22%), (2) AVTIS range measurements to measure the talus growth (˜3.9 × 106 m3, 57%), and (3) rockfall seismicity to measure the pyroclastic flow deposit volumes (˜1.4 × 106 m3, 21%), which gives an overall dense rock equivalent extrusion rate of about 7 m3·s-1. These figures demonstrate how efficient nonexplosive lava dome growth can be in generating large volumes of primary clastic deposits, a process that, by reducing the proportion of erupted lava stored in the summit region, will reduce the likelihood of large hazardous pyroclastic flows.

GEOSCOPE Observatory Recent Developments

NASA Astrophysics Data System (ADS)

Leroy, N.; Pardo, C.; Bonaime, S.; Stutzmann, E.; Maggi, A.

2010-12-01

The GEOSCOPE observatory consists of a global seismic network and a data center. The 31 GEOSCOPE stations are installed in 19 countries, across all continents and on islands throughout the oceans. They are equipped with three component very broadband seismometers (STS1 or STS2) and 24 or 26 bit digitizers, as required by the Federation of Seismic Digital Network (FDSN). In most stations, a pressure gauge and a thermometer are also installed. Currently, 23 stations send data in real or near real time to GEOSCOPE Data Center and tsunami warning centers. In 2009, two stations (SSB and PPTF) have been equipped with warpless base plates. Analysis of one year of data shows that the new installation decreases long period noise (20s to 1000s) by 10 db on horizontal components. SSB is now rated in the top ten long period stations for horizontal components according to the LDEO criteria. In 2010, Stations COYC, PEL and RER have been upgraded with Q330HR, Metrozet electronics and warpless base plates. They have been calibrated with the calibration table CT-EW1 and the software jSeisCal and Calex-EW. Aluminum jars are now installed instead of glass bells. A vacuum of 100 mbars is applied in the jars which improves thermal insulation of the seismometers and reduces moisture and long-term corrosion in the sensor. A new station RODM has just been installed in Rodrigues Island in Mauritius with standard Geoscope STS2 setup: STS2 seismometer on a granite base plate and covered by cooking pot and thermal insulation, it is connected to Q330HR digitizer, active lightning protection, Seiscomp PC and real-time internet connection. Continuous data of all stations are collected in real time or with a delay by the GEOSCOPE Data Center in Paris where they are validated, archived and made available to the international scientific community. Data are freely available to users by different interfaces according data types (see : http://geoscope.ipgp.fr) - Continuous data in real time coming from 23 stations to GEOSCOPE Data Center are available automatically using the seedlink protocol developed by GEOFON (GFZ, Germany). Seedlink also enables to make these data accessible in real time to Tsunami Warning Centers and to other data centers. - Validated continuous waveforms and metadata of all stations are available by using the NetDC system (Networked Data Centers) and Data Handler Interface (DHI, IRIS-DMC) via DHI Clients. Data can be requested from GEOSCOPE Data Center and from other networked centers associated to the FDSN. - A selection of seismograms corresponding to large earthquakes through the GEOSCOPE web portal. - The power spectrum estimates of the seismic noise averaged over sequences of 24 hours for each station. The noise level of the last 10 years of continuous data has been computed and is accessible via the web. The noise level of real time data is computed at day-8. GEOSCOPE data center is networked to the French virtual data center, FOSFORE/RESIF, in order to give a unique access to French seismological data. In Europe, EIDA (European Integrated Data Archive) is operational since June 2009. GEOSCOPE/IPGP is one of the four primary nodes archiving and distributing data inside EIDA. All GEOSCOPE data are available via the European Seismic Portal (http://www.seismicportal.eu).

Level-dependent changes in detection of temporal gaps in noise markers by adults with normal and impaired hearing

PubMed Central

Horwitz, Amy R.; Ahlstrom, Jayne B.; Dubno, Judy R.

2011-01-01

Compression in the basilar-membrane input–output response flattens the temporal envelope of a fluctuating signal when more gain is applied to lower level than higher level temporal components. As a result, level-dependent changes in gap detection for signals with different depths of envelope fluctuation and for subjects with normal and impaired hearing may reveal effects of compression. To test these assumptions, gap detection with and without a broadband noise was measured with 1 000-Hz-wide (flatter) and 50-Hz-wide (fluctuating) noise markers as a function of marker level. As marker level increased, background level also increased, maintaining a fixed acoustic signal-to-noise ratio (SNR) to minimize sensation-level effects on gap detection. Significant level-dependent changes in gap detection were observed, consistent with effects of cochlear compression. For the flatter marker, gap detection that declines with increases in level up to mid levels and improves with further increases in level may be explained by an effective flattening of the temporal envelope at mid levels, where compression effects are expected to be strongest. A flatter effective temporal envelope corresponds to a reduced effective SNR. The effects of a reduction in compression (resulting in larger effective SNRs) may contribute to better-than-normal gap detection observed for some hearing-impaired listeners. PMID:22087921

Caracterización espectroscópica de hielos de interés atmosférico y astrofísico

NASA Astrophysics Data System (ADS)

Escribano, R.

En años recientes se ha incrementado el estudio de procesos físicos y químicos que tienen lugar en la superficie o el interior de hielos, tanto en medios astrofísicos como en la atmósfera terrestre y en otros cuerpos del sistema solar. Se ha comprobado que las partículas heladas actúan como catalizadores de reacciones químicas, que no ocurrirían en su ausencia. En la atmósfera terrestre, es bien conocida la importancia de partículas de hidratos de ácido nítrico, formando las llamadas nubes estratosféricas polares, en los procesos de destrucción de ozono estratosférico. En hielos astrofísicos, átomos como H, C, N y O pueden adherirse o introducirse en la estructura cristalina o amorfa del hielo, y dar lugar a reacciones de formación de moléculas evitando su barrera de activación. Existen partículas heladas en el medio interestelar formando parte de las llamadas nubes moleculares densas y frías, con valores del orden de 106 átomos de H por cm3 y temperaturas entre 3 y 90 K. Alrededor de protoestrellas, pueden formarse hielos de distinta composición, polares o apolares, en las zonas de alejamiento y temperatura decreciente a partir del núcleo caliente. Por su parte, los cometas están formados por un núcleo de hielo y rocas, sobre el que se encuentran adheridas moléculas gaseosas, y una cola, formada por los gases liberados por efecto del calentamiento debido a la radiación solar incidente. En nuestro sistema solar, los polos de La Tierra y de Marte están cubiertos de hielo, así como la mayoría de los cuerpos externos. Los satélites de Júpiter han sido estudiados detalladamente, y se han encontrado en ellos, y en Tritón (satélite de Neptuno), hielos de moléculas como SON2, CO2, N2, CH4 y otros. Para la caracterización espectroscópica de estos hielos se precisan medidas en el laboratorio, aún conociendo la imposibilidad intrínseca de reproducir exactamente las condiciones en que se formaron y se encuentran en los medios astrofísicos. El montaje experimental requiere un sistema que permita alcanzar bajas presiones y temperaturas, formado usualmente por una cámara en cuyo interior se forman películas de hielo de la composición deseada, depositadas sobre un sustrato inerte. Las películas pueden ser a continuación tratadas por diversas técnicas, tales como irradiación UV, bombardeo con electrones o iones, calentamiento y enfriamiento, etc. Habitualmente todos los procesos se controlan por espectroscopía de infrarrojo. La radiación proveniente de un espectrómetro se hace incidir sobre la muestra y se extrae de la cámara mediante ventanas, y se enfoca posteriormente sobre el detector. En el laboratorio de Física Molecular del Instituto de Estructura de la Materia disponemos de un montaje experimental diseñado para el estudio de partículas de hielo similares a las formadas en las nubes estratosféricas polares de nuestra atmósfera. El montaje es similar al descrito anteriormente, excepto en lo que se refiere a las condiciones de presión y temperatura, que son menos estrictas en nuestros experimentos. La extensión de estas condiciones de trabajo a las requeridas en medios astrofísicos es una posibilidad a discutir. Por otra parte, disponemos de un método de cálculo de estructuras periódicas, basado en el programa SIESTA (acrónimo de Spanish Initiative for Electronic Simulations of Thousands of Atoms), que ha proporcionado excelentes resultados en lo relativo a la determinación de estructuras cristalinas y predicción de su espectro infrarrojo, en los sistemas estudiados hasta la fecha, es decir, los hidratos de ácido nítrico de interés atmosféricos. Su aplicación para el estudio de hielos de relevancia astrofísica podría ser del máximo interés.

More Precise Estimation of Lower-Level Interaction Effects in Multilevel Models.

PubMed

Loeys, Tom; Josephy, Haeike; Dewitte, Marieke

2018-01-01

In hierarchical data, the effect of a lower-level predictor on a lower-level outcome may often be confounded by an (un)measured upper-level factor. When such confounding is left unaddressed, the effect of the lower-level predictor is estimated with bias. Separating this effect into a within- and between-component removes such bias in a linear random intercept model under a specific set of assumptions for the confounder. When the effect of the lower-level predictor is additionally moderated by another lower-level predictor, an interaction between both lower-level predictors is included into the model. To address unmeasured upper-level confounding, this interaction term ought to be decomposed into a within- and between-component as well. This can be achieved by first multiplying both predictors and centering that product term next, or vice versa. We show that while both approaches, on average, yield the same estimates of the interaction effect in linear models, the former decomposition is much more precise and robust against misspecification of the effects of cross-level and upper-level terms, compared to the latter.

Cross-Level Effects Between Neurophysiology and Communication During Team Training.

PubMed

Gorman, Jamie C; Martin, Melanie J; Dunbar, Terri A; Stevens, Ronald H; Galloway, Trysha L; Amazeen, Polemnia G; Likens, Aaron D

2016-02-01

We investigated cross-level effects, which are concurrent changes across neural and cognitive-behavioral levels of analysis as teams interact, between neurophysiology and team communication variables under variations in team training. When people work together as a team, they develop neural, cognitive, and behavioral patterns that they would not develop individually. It is currently unknown whether these patterns are associated with each other in the form of cross-level effects. Team-level neurophysiology and latent semantic analysis communication data were collected from submarine teams in a training simulation. We analyzed whether (a) both neural and communication variables change together in response to changes in training segments (briefing, scenario, or debriefing), (b) neural and communication variables mutually discriminate teams of different experience levels, and (c) peak cross-correlations between neural and communication variables identify how the levels are linked. Changes in training segment led to changes in both neural and communication variables, neural and communication variables mutually discriminated between teams of different experience levels, and peak cross-correlations indicated that changes in communication precede changes in neural patterns in more experienced teams. Cross-level effects suggest that teamwork is not reducible to a fundamental level of analysis and that training effects are spread out across neural and cognitive-behavioral levels of analysis. Cross-level effects are important to consider for theories of team performance and practical aspects of team training. Cross-level effects suggest that measurements could be taken at one level (e.g., neural) to assess team experience (or skill) on another level (e.g., cognitive-behavioral). © 2015, Human Factors and Ergonomics Society.

Leadership styles across hierarchical levels in nursing departments.

PubMed

Stordeur, S; Vandenberghe, C; D'hoore, W

2000-01-01

Some researchers have reported on the cascading effect of transformational leadership across hierarchical levels. One study examined this effect in nursing, but it was limited to a single hospital. To examine the cascading effect of leadership styles across hierarchical levels in a sample of nursing departments and to investigate the effect of hierarchical level on the relationships between leadership styles and various work outcomes. Based on a sample of eight hospitals, the cascading effect was tested using correlation analysis. The main sources of variation among leadership scores were determined with analyses of variance (ANOVA), and the interaction effect of hierarchical level and leadership styles on criterion variables was tested with moderated regression analysis. No support was found for a cascading effect of leadership across hierarchical levels. Rather, the variation of leadership scores was explained primarily by the organizational context. Transformational leadership had a stronger impact on criterion variables than transactional leadership. Interaction effects between leadership styles and hierarchical level were observed only for perceived unit effectiveness. The hospital's structure and culture are major determinants of leadership styles.

Chrysotile asbestos exposure associated with removal of automobile exhaust systems (ca. 1945-1975) by mechanics: results of a simulation study.

PubMed

Paustenbach, Dennis J; Madl, Amy K; Donovan, Ellen; Clark, Katherine; Fehling, Kurt; Lee, Terry C

2006-03-01

For decades, asbestos-containing gaskets were used in virtually every system that involved the transport of fluids or gases. Prior to the mid-1970s, some automobile exhaust systems contained asbestos gaskets either at flanges along the exhaust pipes or at the exhaust manifolds of the engine. A limited number of automobile mufflers were lined with asbestos paper. This paper describes a simulation study that characterized personal and bystander exposures to asbestos during the removal of automobile exhaust systems (ca. 1945-1975) containing asbestos gaskets. A total of 16 pre-1974 vehicles with old or original exhaust systems were studied. Of the 16 vehicles, 12 contained asbestos gaskets in the exhaust system and two vehicles had asbestos lining inside the muffler. A total of 82 samples (23 personal, 38 bystander, and 21 indoor background) were analyzed by Phase Contrast Microscopy (PCM) and 88 samples (25 personal, 41 bystander, and 22 indoor background) by Transmission Electron Microscopy (TEM). Only seven of 25 worker samples analyzed by TEM detected asbestos fibers and 18 were below the analytical sensitivity limit (mean 0.013 f/cc, range 0.001-0.074 f/cc). Applying the ratio of asbestos fibers:total fibers (including non-asbestos) as determined by TEM to the PCM results showed an average (1 h) adjusted PCM worker exposure of 0.018 f/cc (0.002-0.04 f/cc). The average (1 h) adjusted PCM airborne concentration for bystanders was 0.008 f/cc (range 0.0008-0.015 f/cc). Assuming a mechanic can replace four automobile single exhaust systems in 1 workday, the estimated 8-h time-weighted average (TWA) for a mechanic performing this work was 0.01 f/cc. Under a scenario where a mechanic might repeatedly conduct exhaust work, these results suggest that exposures to asbestos from work with automobile exhaust systems during the 1950s through the 1970s containing asbestos gaskets were substantially below 0.1 f/cc, the current PEL for chrysotile asbestos, and quite often were not detectable.

An Evaluation of an Aftermarket Local Exhaust Ventilation Device for Suppressing Respirable Dust and Respirable Crystalline Silica Dust from Powered Saws

PubMed Central

Garcia, Alberto; Jones, Erica; Echt, Alan S.; Hall, Ronald M.

2015-01-01

The objective of this study was to quantify the respirable dust and respirable silica exposures of roofing workers using an electric powered circular saw with an aftermarket local exhaust ventilation attachment to cut concrete roofing tiles. The study was conducted to determine whether the local exhaust ventilation attachment was able to control respirable dust and respirable silica exposure below occupational exposure limits. Time-integrated filter samples and direct reading respirable dust concentrations were evaluated. The local exhaust ventilation consisted of a shroud attached to the cutting plane of the saw; the shroud was then connected to a small electric axial fan, which is intended to collect dust at the point of generation. All sampling was conducted with the control in use. Roofers are defined as those individuals who solely lay tiles. Cutters/roofers are defined as those workers who operate the powered saw to cut tiles and also lay tiles. Respirable dust from this evaluation ranged from 0.13 to 6.59 milligrams per cubic meter (mg/m3) with a geometric mean of 0.38 mg/m3 for roofers and from 0.45 to 3.82 mg/m3 with a geometric mean of 1.84 mg/m3 for cutters/roofers. Cutters/roofers usually handle areas close to crevices, edges, or tips of the roof whereas roofers handle areas where complete tiles can be placed. The respirable dust exposures for all cutters/roofers indicated concentrations exceeding the Occupational Safety and Health Administration’s (OSHA) permissible exposure limit (PEL) for respirable dust containing silica; it was also exceeded for some of the roofers. The respirable silica concentrations ranged from 0.04 to 0.15 mg/m3 with an average of 0.09 mg/m3 for roofers, and from 0.13 to 1.21 mg/m3 with an average of 0.48 mg/m3 for cutters/roofers. As with respirable dust, the respirable silica exposures to cutters/roofers were higher than the exposures for roofers. PMID:25148513

Malignant lymphomas (ML) and HIV infection in Tanzania

PubMed Central

2008-01-01

Background HIV infection is reported to be associated with some malignant lymphomas (ML) so called AIDS-related lymphomas (ARL), with an aggressive behavior and poor prognosis. The ML frequency, pathogenicity, clinical patterns and possible association with AIDS in Tanzania, are not well documented impeding the development of preventive and therapeutic strategies. Methods Sections of 176 archival formalin-fixed paraffin-embedded biopsies of ML patients at Muhimbili National Hospital (MNH)/Muhimbili University of Health and Allied Sciences (MUHAS), Tanzania from 1996–2001 were stained for hematoxylin and eosin and selected (70) cases for expression of pan-leucocytic (CD45), B-cell (CD20), T-cell (CD3), Hodgkin/RS cell (CD30), histiocyte (CD68) and proliferation (Ki-67) antigen markers. Corresponding clinical records were also evaluated. Available sera from 38 ML patients were screened (ELISA) for HIV antibodies. Results The proportion of ML out of all diagnosed tumors at MNH during the 6 year period was 4.2% (176/4200) comprising 77.84% non-Hodgkin (NHL) including 19.32% Burkitt's (BL) and 22.16% Hodgkin's disease (HD). The ML tumors frequency increased from 0.42% (1997) to 0.70% (2001) and 23.7% of tested sera from these patients were HIV positive. The mean age for all ML was 30, age-range 3–91 and peak age was 1–20 years. The male:female ratio was 1.8:1. Supra-diaphragmatic presentation was commonest and histological sub-types were mostly aggressive B-cell lymphomas however, no clear cases of primary effusion lymphoma (PEL) and primary central nervous system lymphoma (PCNSL) were diagnosed. Conclusion Malignant lymphomas apparently, increased significantly among diagnosed tumors at MNH between 1996 and 2001, predominantly among the young, HIV infected and AIDS patients. The frequent aggressive clinical and histological presentation as well as the dominant B-immunophenotype and the HIV serology indicate a pathogenic association with AIDS. Therefore, routine HIV screening of all malignant lymphoma patients at MNH is necessary to enable comprehensive ARL diagnosis and formulation of preventive and therapeutic protocols. PMID:18577266

Chlorine Stable Isotopes to reveal contribution of magmatic chlorine in subduction zones: the case of the Kamchatka-Kuril and the Lesser Antilles Volcanic Arcs

NASA Astrophysics Data System (ADS)

Agrinier, Pierre; Shilobreeva, Svetlana; Bardoux, Gerard; Michel, Agnes; Maximov, Alexandr; Kalatcheva, Elena; Ryabinin, Gennady; Bonifacie, Magali

2015-04-01

By using the stable isotopes of chlorine (δ 37Cl), we have shown that magmatic chlorine (δ 37Cl ≤ -0.6 ‰ [1]) is different from surface chlorine (δ 37Cl ≈ 0 ‰ [1]) in hydrothermal system of Soufrière and Montagne Pelé from the young arc volcanic system of Lesser Antilles. First measurements on condensed chlorides from volcanic gases (e.g. [2], [3]) did not permitted to get sensible δ 37Cl values on degassed chlorine likely because chlorine isotopes are fractionated during the HClgas - chloride equilibrium in the fumaroles or during sampling artifacts. Therefore we have developed an alternative strategy based on the analysis of chloride in thermal springs, streams, sout{f}lowing on the flanks of the volcanoes. Due to the highly hydrophilic behavior of Cl, we hypothesize that thermal springs incorporate chlorine without fractionation of chlorine isotopes and might reflect the chlorine isotopic composition degassed by magmas [1]. Indeed Thermal spring with low δ 37Cl chlorides (≤ -0.6 perthousand{}) are linked with magmatic volatiles characters (3He ratio at 5 Ra at and δ 13C CO2 quad ≈ -3 perthousand{}). To go further in the potentiality of using the Chlorine isotopes to reveal contribution of magmatic chlorine in volcanic systems, we have started the survey of thermal springs and wells waters in the Kamchatka-Kuril volcanic mature Arc (on sites Mutnovsky, Paratunka, Nalychevsky, Khodutkinsky, Paramushir Island, identified by Taran, 2009 [4] for concentrations of chloride). Preliminary results show δ 37Cl values ranging from 0.5 to -0.2 ‰ and generally higher chloride concentrations. The δ 37Cl values are higher than the value recorded for the young arc volcanic system of lesser Antilles. At present moment very few negative δ 37Cl have been measured in the Kamchatka-Kuril volcanic mature Arc. [1] Li et al., 2015 EPSL in press. [2] Sharp et al. 2010 GCA. [3] Rizzo et al., 2013, EPSL, 371, 134. [4] Taran, 2009, GCA, 73, 1067

Unravelling thermal emissivity spectra of the main minerals on Mercury's surface by comparison with ab initio calculated IR-HT vibrational frequencies

NASA Astrophysics Data System (ADS)

Stangarone, C.; Helbert, J.; Tribaudino, M.; Maturilli, A.; D'Amore, M.; Ferrari, S.; Prencipe, M.

2015-12-01

Spectral signatures of minerals are intimately related to the crystal structure; therefore they may represent a remote sensing model to determine surface composition of planetary bodies, by analysing their spectral reflectance and emission. However, one of the most critical point is data interpretation considering planetary surfaces, as Mercury, where the changes in spectral characteristics are induced by the high temperatures conditions (Helbert et al., 2013). The aim of this work is to interpret the experimental thermal emissivity spectra with an innovative approach: simulating IR spectra of the main mineral families that compose the surface of Mercury, focusing on pyroxenes (Sprague et al., 2002), both at room and high temperature, exploiting the accuracy of ab initio quantum mechanical calculations, by means of CRYSTAL14 code (Dovesi et al., 2014). The simulations will be compared with experimental emissivity measurements of planetary analogue samples at temperature up to 1000K, performed at Planetary Emissivity Laboratory (PEL) by Institute of Planetary Research (DLR, Berlin). Results will be useful to create a theoretical background to interpret HT-IR emissivity spectra that will be collected by the Mercury Radiometer and Thermal Infrared Spectrometer (MERTIS), a spectrometer developed by DLR that will be on board of the ESA BepiColombo Mercury Planetary Orbiter (MPO) scheduled for 2017. The goal is to point out the most interesting spectral features for a geological mapping of Mercury and other rocky bodies, simulating the environmental conditions of the inner planets of Solar System. Dovesi R., Saunders V. R., Roetti C., Orlando R., Zicovich-Wilson C. M., Pascale F., Civalleri B., Doll K., Harrison N. M., Bush I. J., D'Arco P., Llunell M., Causà M. & Noël Y. 2014. CRYSTAL14 User's Manual, University of Torino. Sprague, A. L., Emery, J. P., Donaldson, K. L., Russell, R. W., Lynch, D. K., & Mazuk, A. L. (2002). Mercury: Mid-infrared (3-13.5 μm) observations show heterogeneous composition, presence of intermediate and basic soil types, and pyroxene. Meteoritics & Planetary Science, 37(9), 1255-1268.

An evaluation of an aftermarket local exhaust ventilation device for suppressing respirable dust and respirable crystalline silica dust from powered saws.

PubMed

Garcia, Alberto; Jones, Erica; Echt, Alan S; Hall, Ronald M

2014-01-01

The objective of this study was to quantify the respirable dust and respirable silica exposures of roofing workers using an electric-powered circular saw with an aftermarket local exhaust ventilation attachment to cut concrete roofing tiles. The study was conducted to determine whether the local exhaust ventilation attachment was able to control respirable dust and respirable silica exposure below occupational exposure limits (OELs). Time-integrated filter samples and direct reading respirable dust concentrations were evaluated. The local exhaust ventilation consisted of a shroud attached to the cutting plane of the saw; the shroud was then connected to a small electric axial fan, which is intended to collect dust at the point of generation. All sampling was conducted with the control in use. Roofers are defined as those individuals who only lay tiles. Cutters/roofers are defined as those workers who operate the powered saw to cut tiles and also lay tiles. Respirable dust from this evaluation ranged from 0.13 to 6.59 milligrams per cubic meter (mg/m(3)) with a geometric mean of 0.38 mg/m(3) for roofers and from 0.45 to 3.82 mg/m(3) with a geometric mean of 1.84 mg/m(3) for cutters/roofers. Cutters/roofers usually handle areas close to crevices, edges, or tips of the roof whereas roofers handle areas where complete tiles can be placed. The respirable dust exposures for all cutters/roofers indicated concentrations exceeding the Occupational Safety and Health Administration's (OSHA) permissible exposure limit (PEL) for respirable dust containing silica; it was also exceeded for some of the roofers. The respirable silica concentrations ranged from 0.04 to 0.15 mg/m(3) with a geometric mean of 0.09 mg/m(3) for roofers, and from 0.13 to 1.21 mg/m(3) with a geometric mean of 0.48 mg/m(3) for cutters/roofers. As with respirable dust, the respirable silica exposures for cutters/roofers were higher than the exposures for roofers.

Characterization of bulbospongiosus muscle reflexes activated by urethral distension in male rats.

PubMed

Tanahashi, Masayuki; Karicheti, Venkateswarlu; Thor, Karl B; Marson, Lesley

2012-10-01

The urethrogenital reflex (UGR) is used as a surrogate model of the autonomic and somatic nerve and muscle activity that accompanies ejaculation. The UGR is evoked by distension of the urethra and activation of penile afferents. The current study compares two methods of elevating urethral intraluminal pressure in spinalized, anesthetized male Sprague-Dawley rats (n = 60). The first method, penile extension UGR, involves extracting the penis from the foreskin, so that urethral pressure rises due to a natural anatomical flexure in the penis. The second method, penile clamping UGR, involves penile extension UGR with the addition of clamping of the glans penis. Groups of animals were prepared that either received no additional treatment, surgical shams, or received bilateral nerve cuts (4 nerve cut groups): either the pudendal sensory nerve branch (SbPN), the pelvic nerves, the hypogastric nerves, or all three nerves. Penile clamping UGR was characterized by multiple bursts, monitored by electromyography (EMG) of the bulbospongiosus muscle (BSM) accompanied by elevations in urethral pressure. The penile clamping UGR activity declined across multiple trials and eventually resulted in only a single BSM burst, indicating desensitization. In contrast, the penile extension UGR, without penile clamping, evoked only a single BSM EMG burst that showed no desensitization. Thus, the UGR is composed of two BSM patterns: an initial single burst, termed urethrobulbospongiosus (UBS) reflex and a subsequent multiple bursting pattern (termed ejaculation-like response, ELR) that was only induced with penile clamping urethral occlusion. Transection of the SbPN eliminated the ELR in the penile clamping model, but the single UBS reflex remained in both the clamping and extension models. Pelvic nerve (PelN) transection increased the threshold for inducing BSM activation with both methods of occlusion but actually unmasked an ELR in the penile extension method. Hypogastric nerve (HgN) cuts did not significantly alter any parameter. Transection of all three nerves eliminated BSM activation completely. In conclusion, penile clamping occlusion recruits penile and urethral primary afferent fibers that are necessary for an ELR. Urethral distension without significant penile afferent activation recruits urethral primary afferent fibers carried in either the pelvic or pudendal nerve that are necessary for the single-burst UBS reflex.

Practice guideline update summary: Botulinum neurotoxin for the treatment of blepharospasm, cervical dystonia, adult spasticity, and headache

PubMed Central

Simpson, David M.; Hallett, Mark; Ashman, Eric J.; Comella, Cynthia L.; Green, Mark W.; Gronseth, Gary S.; Armstrong, Melissa J.; Gloss, David; Potrebic, Sonja; Jankovic, Joseph; Karp, Barbara P.; Naumann, Markus; So, Yuen T.; Yablon, Stuart A.

2016-01-01

Objective: To update the 2008 American Academy of Neurology (AAN) guidelines regarding botulinum neurotoxin for blepharospasm, cervical dystonia (CD), headache, and adult spasticity. Methods: We searched the literature for relevant articles and classified them using 2004 AAN criteria. Results and recommendations: Blepharospasm: OnabotulinumtoxinA (onaBoNT-A) and incobotulinumtoxinA (incoBoNT-A) are probably effective and should be considered (Level B). AbobotulinumtoxinA (aboBoNT-A) is possibly effective and may be considered (Level C). CD: AboBoNT-A and rimabotulinumtoxinB (rimaBoNT-B) are established as effective and should be offered (Level A), and onaBoNT-A and incoBoNT-A are probably effective and should be considered (Level B). Adult spasticity: AboBoNT-A, incoBoNT-A, and onaBoNT-A are established as effective and should be offered (Level A), and rimaBoNT-B is probably effective and should be considered (Level B), for upper limb spasticity. AboBoNT-A and onaBoNT-A are established as effective and should be offered (Level A) for lower-limb spasticity. Headache: OnaBoNT-A is established as effective and should be offered to increase headache-free days (Level A) and is probably effective and should be considered to improve health-related quality of life (Level B) in chronic migraine. OnaBoNT-A is established as ineffective and should not be offered for episodic migraine (Level A) and is probably ineffective for chronic tension-type headaches (Level B). PMID:27164716

Empirically Examining the Performance of Approaches to Multi-Level Matching to Study the Effect of School-Level Interventions

ERIC Educational Resources Information Center

Hallberg, Kelly; Cook, Thomas D.; Figlio, David

2013-01-01

The goal of this paper is to provide guidance for applied education researchers in using multi-level data to study the effects of interventions implemented at the school level. Two primary approaches are currently employed in observational studies of the effect of school-level interventions. One approach employs intact school matching: matching…

Using panel data to determine the effect of advertising on brand-level distilled spirits sales.

PubMed

Gius, M P

1996-01-01

The purpose of the present study is to determine the effect that brand-level advertising has on brand-level spirits demand. Using a panel data set consisting of 16 brands and 14 years of data, a fixed effects model of brand-level spirits demand was estimated. It was found that own-brand advertising, income, rival-brand price, a time trend and brand loyalty all have a significant effect on brand-level spirits demand. These results indicate that brand-level spirits advertising results only in brand switching and does not increase the overall size of the market.

Application of Adjusted Canonical Correlation Analysis (ACCA) to study the association between mathematics in Level 1 and Level 2 and performance of engineering disciplines in Level 2

NASA Astrophysics Data System (ADS)

Peiris, T. S. G.; Nanayakkara, K. A. D. S. A.

2017-09-01

Mathematics plays a key role in engineering sciences as it assists to develop the intellectual maturity and analytical thinking of engineering students and exploring the student academic performance has received great attention recently. The lack of control over covariates motivates the need for their adjustment when measuring the degree of association between two sets of variables in Canonical Correlation Analysis (CCA). Thus to examine the individual effects of mathematics in Level 1 and Level 2 on engineering performance in Level 2, two adjusted analyses in CCA: Part CCA and Partial CCA were applied for the raw marks of engineering undergraduates for three different disciplines, at the Faculty of Engineering, University of Moratuwa, Sri Lanka. The joint influence of mathematics in Level 1 and Level 2 is significant on engineering performance in Level 2 irrespective of the engineering disciplines. The individual effect of mathematics in Level 2 is significantly higher compared to the individual effect of mathematics in Level 1 on engineering performance in Level 2. Furthermore, the individual effect of mathematics in Level 1 can be negligible. But, there would be a notable indirect effect of mathematics in Level 1 on engineering performance in Level 2. It can be concluded that the joint effect of mathematics in both Level 1 and Level 2 is immensely beneficial to improve the overall academic performance at the end of Level 2 of the engineering students. Furthermore, it was found that the impact mathematics varies among engineering disciplines. As partial CCA and partial CCA are not widely explored in applied work, it is recommended to use these techniques for various applications.

Adjacent level effects of bi level disc replacement, bi level fusion and disc replacement plus fusion in cervical spine--a finite element based study.

PubMed

Faizan, Ahmad; Goel, Vijay K; Biyani, Ashok; Garfin, Steven R; Bono, Christopher M

2012-03-01

Studies delineating the adjacent level effect of single level disc replacement systems have been reported in literature. The aim of this study was to compare the adjacent level biomechanics of bi-level disc replacement, bi-level fusion and a construct having adjoining level disc replacement and fusion system. In total, biomechanics of four models- intact, bi level disc replacement, bi level fusion and fusion plus disc replacement at adjoining levels- was studied to gain insight into the effects of various instrumentation systems on cranial and caudal adjacent levels using finite element analysis (73.6N+varying moment). The bi-level fusion models are more than twice as stiff as compared to the intact model during flexion-extension, lateral bending and axial rotation. Bi-level disc replacement model required moments lower than intact model (1.5Nm). Fusion plus disc replacement model required moment 10-25% more than intact model, except in extension. Adjacent level motions, facet loads and endplate stresses increased substantially in the bi-level fusion model. On the other hand, adjacent level motions, facet loads and endplate stresses were similar to intact for the bi-level disc replacement model. For the fusion plus disc replacement model, adjacent level motions, facet loads and endplate stresses were closer to intact model rather than the bi-level fusion model, except in extension. Based on our finite element analysis, fusion plus disc replacement procedure has less severe biomechanical effects on adjacent levels when compared to bi-level fusion procedure. Bi-level disc replacement procedure did not have any adverse mechanical effects on adjacent levels. Copyright © 2011 Elsevier Ltd. All rights reserved.

The Effect of Dihydroxyacetone on the Liquid Storage Properties of Human Blood.

DTIC Science & Technology

Addition of dihydroxyacetone (DHA) to acid-citrate-phosphate (ACD) blood is effective in partially maintaining 2,3- diphosphoglycerate levels for a...period of 21 to 28 days. DHA has no effect on adenosine triphosphate (ATP) levels or cell viability. The overall effect of adenine with DHA is...unfavorable since it retards the effect of the DHA while only slightly raising ATP levels . DHA may be valuable in maintaining increased hemoglobin function levels throughout the present 21 day storage period. (Author)