Effectiveness of nanoparticle exposure mitigation measures in industrial settings.

Inhalation of airborne nanoparticles is a well-known source of potentially health-hazardous occupational exposures. Effective mitigation measures are necessary to reduce exposure, but also challenging to implement due to the different characteristics of each individual emission source and industrial scenario. The present paper describes four different exposure case studies in the ceramic industry and quantifies the effectiveness of mitigation strategies implemented during: ceramic tile processing by thermal spraying, laser ablation, the use of diesel engines, and tile firing. The mitigation measures for exposure reduction were tailored to each industrial scenario. The NP removal efficiency of source enclosure (partial/full) combined with local exhaust ventilation (LEV) were quantified to range between 65 and 85% when the enclosure was partial. The efficiency reached 99% with full enclosure and vigorous ventilation (Air Change per Hour; ACH = 132 h-1). The elimination of the source was the optimal strategy to minimize exposure in the case of diesel forklifts use. The conventional ceramic kilns used intensively (>10 years) generated high NP exposure concentrations (>106/cm3). Appropriate maintenance and enhanced sealing enabled the reduction of exposure down to 52% of the initial value. It must be added that technologically advanced kilns, enabled even greater NP reductions (down to 84%), compared to the conventional ones. This proves technological improvements can lead to significant reduction of work exposures. This work evidences the need for tailored mitigation measures due to the broad variety of potential sources and activities in industrial scenarios. The quantitative efficiency rates reported here may be valuable for the adequate parametrization of exposure prediction and risk assessment models.

Towards precision quantification of contamination in metagenomic sequencing experiments.

Metagenomic next-generation sequencing (mNGS) experiments involving small amounts of nucleic acid input are highly susceptible to erroneous conclusions resulting from unintentional sequencing of occult contaminants, especially those derived from molecular biology reagents. Recent work suggests that, for any given microbe detected by mNGS, an inverse linear relationship between microbial sequencing reads and sample mass implicates that microbe as a contaminant. By associating sequencing read output with the mass of a spike-in control, we demonstrate that contaminant nucleic acid can be quantified in order to identify the mass contributions of each constituent. In an experiment using a high-resolution (n = 96) dilution series of HeLa RNA spanning 3-logs of RNA mass input, we identified a complex set of contaminants totaling 9.1 ± 2.0 attograms. Given the competition between contamination and the true microbiome in ultra-low biomass samples such as respiratory fluid, quantification of the contamination within a given batch of biological samples can be used to determine a minimum mass input below which sequencing results may be distorted. Rather than completely censoring contaminant taxa from downstream analyses, we propose here a statistical approach that allows separation of the true microbial components from the actual contribution due to contamination. We demonstrate this approach using a batch of n = 97 human serum samples and note that despite E. coli contamination throughout the dataset, we are able to identify a patient sample with significantly more E. coli than expected from contamination alone. Importantly, our method assumes no prior understanding of possible contaminants, does not rely on any prior collection of environmental or reagent-only sequencing samples, and does not censor potentially clinically relevant taxa, thus making it a generalized approach to any kind of metagenomic sequencing, for any purpose, clinical or otherwise.

Diets and trophic niches of the main commercial fish species from the Celtic Sea.

The characterization and quantification of diets of nine commercially important Celtic Sea fish species (black-bellied angler Lophius budegassa, blue whiting Micromesistius poutassou, Atlantic cod Gadus morhua, haddock Melanogrammus aeglefinus, European hake Merluccius merluccius, megrim Lepidorhombus whiffiagonis, European plaice Pleuronectes platessa, common sole Solea solea and whiting Merlangius merlangus) was undertaken November 2014 and November 2015 to gain a better understanding of fish feeding strategies, prey preferences, competition for resources and, more generally, increases knowledge of marine ecosystem functioning. Prey were classified into 39 taxonomic groups. A feeding overlap index and multivariate analyses were used to classify the fishes into four main trophic groups where interspecific competition for resources may be important: piscivorous species, omnivorous species, planktivorous species and invertebrate benthic feeders. Ontogenetic changes in diet were also considered for L. budegassa, G. morhua, M. aeglefinus, M. merluccius and M. merlangus through partitioning into size classes. This revealed an important shift in the diet of M. merluccius from omnivory to piscivory, whereas M. aeglefinus exhibited no significant ontogenetic change in diet, remaining an invertebrate benthic feeder. Feeding strategies of these species were also investigated using the Shannon niche-breadth index and other descriptors, such as the total number of taxonomic groups of prey and the mean number of prey in gut contents.

Cryo-conditioned rocky coast systems: A case study from Wilczekodden, Svalbard.

This paper presents the results of an investigation into the processes controlling development of a cryo-conditioned rock coast system in Hornsund, Svalbard. A suite of nested geomorphological and geophysical methods have been applied to characterise the functioning of rock cliffs and shore platforms influenced by lithological control and geomorphic processes driven by polar coast environments. Electrical resistivity tomography (ERT) surveys have been used to investigate permafrost control on rock coast dynamics and reveal the strong interaction with marine processes in High Arctic coastal settings. Schmidt hammer rock tests, demonstrated strong spatial control on the degree of rock weathering (rock strength) along High Arctic rock coasts. Elevation controlled geomorphic zones are identified and linked to distinct processes and mechanisms, transitioning from peak hardness values at the ice foot through the wave and storm dominated scour zones to the lowest values on the cliff tops, where the effects of periglacial weathering dominate. Observations of rock surface change using a traversing micro-erosion meter (TMEM) indicate that significant changes in erosion rates occur at the junction between the shore platform and the cliff toe, where rock erosion is facilitated by frequent wetting and drying and operation of nivation and sea ice processes (formation and melting of snow patches and icefoot complexes). The results are synthesised to propose a new conceptual model of High Arctic rock coast systems, with the aim of contributing towards a unifying concept of cold region landscape evolution and providing direction for future research regarding the state of polar rock coasts.

Dynamic outcome prediction in a socio-demographically diverse population-based cohort of extremely preterm neonates.

OBJECTIVE: Accurate outcome prediction is crucial for counseling parents and providing individualized treatment to extremely premature infants. We sought to improve upon existing prediction model by using a diverse population-based cohort of extremely premature live births (⩽28 weeks' gestation) for survival and survival without severe neonatal morbidity at different times throughout the first week of life and to evaluate potential differences by race/ethnicity and maternal education. STUDY DESIGN: Retrospective cohort study of all California live births from 2007 through 2011 with linked birth, death and hospital discharge records. RESULTS: A total of 6009 infants were included. In the validation data set at time of delivery, the area under the receiver-operating characteristic curve for the model containing all predictors was 0.863 for survival and 0.789 for survival without severe morbidity. The marginal probability of survival without severe neonatal morbidity of an Asian infant born to a mother with <12 years of education compared with the reference (Caucasian infant, mother with ⩾12 years of education) was -0.23 (95% confidence interval (CI) -0.31 to -0.15) for all infants at time of birth and -0.28 (95% CI -0.39 to -0.18) for infants with attempted resuscitation. Notably, no other differences by racial/ethnic category and maternal education emerged. CONCLUSIONS: Probabilities of survival and survival without major morbidity change rapidly throughout the first week of life. Extremely premature infants born to Asian mothers with less than a high school education appear to have a lower probability to survive without significant morbidity compared with their Caucasian peers.

Risk of preterm birth among women using drugs during pregnancy with elevated α-fetoprotein.

OBJECTIVE: Examine the risk of preterm birth (PTB) among women who use drugs during pregnancy and have elevated α-fetoprotein (AFP). STUDY DESIGN: The sample included California singleton live births in 2005 to 2010 contained within a hospital discharge database linked to the Prenatal Screening Program. A selection of mothers who did not use drugs was selected at a ratio of 4:1. Risk of PTB was calculated using adjusted odds ratios and 95% confidence intervals (CIs) for women who did or did not use drugs by their AFP percentile. RESULTS: We identified 7190 women who used drugs and selected 28 760 women who did not. Of women using cocaine with AFP ⩾95th percentile, 43.8% delivered prematurely. Women using drugs with AFP ⩾95th percentile were 11 to 35 times as likely to deliver <32 weeks. CONCLUSION: The combination of drug use and elevated AFP results in high rates of PTB. This combination results in an additive risk.

Interpregnancy interval after live birth or pregnancy termination and estimated risk of preterm birth: a retrospective cohort study.

OBJECTIVES: We assessed whether interpregnancy interval (IPI) length after live birth and after pregnancy termination was associated with preterm birth (PTB). DESIGN: Multiyear birth cohort. SETTINGS: Fetal death, birth and infant death certificates in California merged with Office of Statewide Health Planning and Development. POPULATION: One million California live births (2007-10) after live birth and after pregnancy termination. METHODS: Logistic regression was used to estimate odds ratios (ORs) of PTB of 20-36 weeks of gestation and its subcategories for IPIs after a live birth and after a pregnancy termination. We used conditional logistic regression (two IPIs/mother) to investigate associations within mothers. MAIN OUTCOME MEASURE: PTB relative to gestations of ≥ 37 weeks. RESULTS: Analyses included 971 211 women with IPI after live birth, and 138 405 women with IPI after pregnancy termination with 30.6% and 74.6% having intervals of <18 months, respectively. IPIs of <6 months or 6-11 months after live birth showed increased odds of PTB adjusted ORs for PTB of 1.71 (95% CI 1.65-1.78) and 1.20 (95% CI 1.16-1.24), respectively compared with intervals of 18-23 months. An IPI >36 months (versus 18-23 months) was associated with increased odds for PTB. Short IPI after pregnancy termination showed a decreased OR of 0.87 (95% CI 0.81-0.94). The within-mother analysis showed the association of increased odds of PTB for short IPI, but not for long IPI. CONCLUSIONS: Women with IPI <1 or >3 years after a live birth were at increased odds of PTB-an important group for intervention to reduce PTB. Short IPI after pregnancy termination was associated with reduced odds for PTB and needs to be further explored. TWEETABLE ABSTRACT: Short and long IPI after live birth, but not after pregnancy termination, showed increased odds for PTB.

Population-based risks of mortality and preterm morbidity by gestational age and birth weight.

OBJECTIVE: The objective of this study is to examine the effect of small or large for gestational age (SGA/LGA) status on mortality and morbidity by gestational age. STUDY DESIGN: Logistic binomial regression was used to calculate relative risks (RRs) and 95% confidence intervals for infant mortality and preterm morbidities for SGA or LGA compared with appropriately grown (AGA) deliveries stratified by gestational age group. RESULTS: Compared with AGA infants of similar gestational age, SGA infants were at increased risk for infant mortality. Mortality risk was decreased for LGA infants born between 25 and 27 weeks (RR: 0.6) but increased for LGA infants born between 28 and 31 weeks (RR: 1.9). Risk of preterm morbidity was increased for SGA infants born between 28 and 38 weeks, but decreased for LGA infants born before 37 weeks. CONCLUSION: This study demonstrates the importance of considering birth weight for gestational age when evaluating morbidity and mortality risks.

Outcomes of pregnancies with more than one positive prenatal screening result in the first or second trimester.

OBJECTIVE: To describe adverse outcomes and fetal abnormalities in women with a positive prenatal screening result for more than one disorder. STUDY DESIGN: Study participants were drawn from a population of 452 901 women pregnant with singletons entering the California Prenatal Screening Program in their first-trimester. Risk assessment was provided for trisomy 21 and trisomy 18 in the first-trimester and trisomy 21, trisomy 18, neural tube defects, and Smith-Lemli-Opitz syndrome in the second-trimester. Inclusion in this study required positive screening for more than one of the screened conditions and a completed outcome of pregnancy survey. RESULTS: A total of 874 women met our study inclusion criteria. Over 25% of these pregnancies had a fetus with a chromosomal abnormality. Of the euploid pregnancies, 6.9% had a fetus with a major birth defect. Of the pregnancies with a fetus with neither a chromosomal abnormality nor a major birth defect, 9.3% ended in fetal demise. Overall, more than 50% of women with multiple positive screening results had either a fetus with a birth defect or a poor pregnancy outcome. CONCLUSION: Although it is rare to screen positive for more than one condition, such results indicate a very high risk for chromosomal abnormality, fetal demise, or structural abnormality.

Maternal characteristics and mid-pregnancy serum biomarkers as risk factors for subtypes of preterm birth.

OBJECTIVE: To examine the relationship between maternal characteristics, serum biomarkers and preterm birth (PTB) by spontaneous and medically indicated subtypes. DESIGN: Population-based cohort. SETTING: California, United States of America. POPULATION: From a total population of 1 004 039 live singleton births in 2009 and 2010, 841 665 pregnancies with linked birth certificate and hospital discharge records were included. METHODS: Characteristics were compared for term and preterm deliveries by PTB subtype using logistic regression and odds ratios adjusted for maternal characteristics and obstetric factors present in final stepwise models and 95% confidence intervals. First-trimester and second-trimester serum marker levels were analysed in a subset of 125 202 pregnancies with available first-trimester and second-trimester serum biomarker results. MAIN OUTCOME MEASURE: PTB by subtype. RESULTS: In fully adjusted models, ten characteristics and three serum biomarkers were associated with increased risk in each PTB subtype (Black race/ethnicity, pre-existing hypertension with and without pre-eclampsia, gestational hypertension with pre-eclampsia, pre-existing diabetes, anaemia, previous PTB, one or two or more previous caesarean section(s), interpregnancy interval ≥ 60 months, low first-trimester pregnancy-associated plasma protein A, high second-trimester α-fetoprotein, and high second-trimester dimeric inhibin A). These risks occurred in 51.6-86.2% of all pregnancies ending in PTB depending on subtype. The highest risk observed was for medically indicated PTB <32 weeks in women with pre-existing hypertension and pre-eclampsia (adjusted odds ratio 89.7, 95% CI 27.3-111.2). CONCLUSIONS: Our findings suggest a shared aetiology across PTB subtypes. These commonalities point to targets for further study and exploration of risk reduction strategies. TWEETABLE ABSTRACT: Findings suggest a shared aetiology across preterm birth subtypes. Patterns may inform risk reduction efforts.

Maternal serum markers, characteristics and morbidly adherent placenta in women with previa.

OBJECTIVE: To examine associations with morbidly adherent placenta (MAP) among women with placenta previa. STUDY DESIGN: Women with MAP (cases) and previa alone (controls) were identified from a cohort of 236,714 singleton pregnancies with both first and second trimester prenatal screening, and live birth and hospital discharge records; pregnancies with aneuploidies and neural tube or abdominal wall defects were excluded. Logistic binomial regression was used to compare cases with controls. RESULT: In all, 37 cases with MAP and 699 controls with previa alone were included. Risk for MAP was increased among multiparous women with pregnancy-associated plasma protein-A (PAPP-A) ⩾95th percentile (⩾2.63 multiple of the median (MoM); adjusted OR (aOR) 8.7, 95% confidence interval (CI) 2.8 to 27.4), maternal-serum alpha fetoprotein (MS-AFP) ⩾95th percentile (⩾1.79 MoM; aOR 2.8, 95% CI 1.0 to 8.0), and 1 and ⩾2 prior cesarean deliveries (CDs; aORs 4.4, 95% CI 1.5 to 13.6 and 18.4, 95% CI 5.9 to 57.5, respectively). CONCLUSION: Elevated PAPP-A, elevated MS-AFP and prior CDs are associated with MAP among women with previa.

The role of mediastinoscopy in the diagnosis of thoracic disease: one-year single center experience.

Our experience of using mediastinoscopy for the diagnosis of enlarged mediastinal lymph nodes or mediastinal mass is presented in this study. We reviewed 54 consecutive patients (34 men and 20 women) with mediastinal pathology of varied etiologies who underwent a standard cervical mediastinoscopy from January to December 2012. The histological results were positive in 32 cases (59.2%), and negative in 22 cases (40.8%). Transient laryngeal recurrent nerve palsy manifested as prolonged hoarseness of voice was the only minor complication in 3 cases (5.5%). The sensitivity of the procedure was 72%, and the specificity was 100%. We recommend the use of a mediastinoscopy in the staging of lung cancer and the diagnosis of mediastinal mass when other non-invasive procedures are ineffective.

Freezing/thawing effects on anaerobic digestion of mixed sewage sludge.

This study examined the effects of freezing/thawing disintegration on the characteristics of mixed (primary and waste) sewage sludge from municipal wastewater treatment plants. It also assessed the effects of freezing/thawing on anaerobic digestion, and its consequences for biogas production and digester supernatant quality. Freezing/thawing caused a decrease of more than 10% in the total chemical oxygen demand (COD), total nitrogen (TN), volatile solids (VS) and total solids (TS). A simultaneous doubling of the soluble COD and volatile fatty acids (VFA) occurred. Release of nitrogen and phosphorus compounds was also found. The biogas yield obtained from frozen/thawed sludge was 1.31 m(3) kg(-1) of removed VS; this exceeded approximately 1.5 times the value for the raw sludge. On the basis of the global mass balance it was indicated that freezing/thawing of the mixed sewage sludge followed by anaerobic digestion could be considered as a "double-phase digestion" rather than a pre-treatment method.

EU demonstration project for separate discharge and treatment of urine, faeces and greywater--part I: results.

The main aim of this EU demonstration project was to test two new sanitation concepts to determine if these concepts are more sustainable, compared with the conventional sanitation system, particularly with regard to nutrient recycling. Two different sanitation concepts were tested. One concept comprised the use of gravity separation toilets, the other used vacuum separation toilets. Results from a life-cycle-assessment investigation show that the new sanitation concepts are more sustainable. A cost analysis for an existing residential area did not prove lower costs for the new sanitation concepts in this special case. The experience from this demonstration project shows that prior to a widespread use of the new sanitation concepts, several improvements have to be made. One important issue is the improvement of separation toilets. Since nutrient recycling, water saving and reuse as well energy reduction become more and more important, further research should be undertaken in this field.

EU demonstration project for separate discharge and treatment of urine, faeces and greywater--part II: cost comparison of different sanitation systems.

The experience from the EU demonstration project was used for a cost analysis of different sanitation systems with regard to nutrient recycling. The analysis was made for an existing residential area, for which the different sanitation systems have been applied. The cost calculations were made for a lifetime of 50 years. The multiple sewer systems cause higher investment costs, mainly for the installation of the additional facilities; the investment costs for the treatment are lower. The cost analysis did not prove lower costs for the new sanitation concepts in this special case in comparison with the conventional system. Economic benefits are demonstrated for the operation costs. The result will be reinforced by the consideration of an increase of the energy costs. The revenues for the nutrient related products have only a very small impact on the result.

Effect of magnitude and timing of maternal pregnancy blood lead (Pb) levels on birth outcomes.

OBJECTIVE: Associations between magnitude and timing of maternal pregnancy blood lead (Pb) levels (BLLs), birth weight, and total days of gestation were examined, as well as associations with related clinical diagnoses of low birth weight (LBW), preterm, and small-for-gestational-age (SGA) birth. STUDY DESIGN: Among a sample of 262 mother-infant pairs studied retrospectively, one-way analysis of variance and regression statistics were used to measure the relationship between level of maternal pregnancy BLLs and birth outcomes while controlling for key maternal and newborn factors. RESULTS: Women with maximum pregnancy BLLs (max-PBLLs) > or =10 microg/dl tended to give birth earlier and their babies were at substantially increased risk for preterm and SGA birth. By holding other explanatory factors constant, each unit increase in max-PBLL above 10 mug/dl was found to be associated with a decrease of -0.3 in total days of gestation. Compared to women with lower levels, women with max-PBLLs > or =10 microg/dl were at a threefold increased risk for preterm birth (adjusted OR=3.2, 95% CI 1.2-7.4) and more than a fourfold increased risk for having an SGA infant (adjusted OR=4.2, 1.3-13.9). Second trimester maximum BLLs > or =10 microg/dl were associated with a steep decrease in total days of gestation (a decrease of -1.0 days per each unit increase above 10 microg/dl). CONCLUSIONS: These data provide evidence of the adverse effects of maternal pregnancy BLLs, particularly when levels are > or =10 microg/dl. Prenatal Pb exposure at these levels was associated with significant decreases in total days of gestation and an increased risk of preterm and SGA birth.

Stability of cefotaxime sodium in solid state.

The influence of temperature and relative humidity on the stability of cefotaxime sodium in the solid state was investigated. Changes in the concentration of cefotaxime sodium were followed by a HPLC method with UV detection. The kinetic and thermodynamic parameters of the decomposition reaction were calculated.

An inverted repeat triggers cytosine methylation of identical sequences in Arabidopsis.

The Wassilewskija (WS) strain of Arabidopsis has four PAI genes at three sites: an inverted repeat at one locus plus singlet genes at two unlinked loci. These four genes are methylated over their regions of DNA identity. In contrast, the Columbia (Col) strain has three singlet PAI genes with no methylation. To test the hypothesis that the WS inverted repeat locus triggers methylation of unlinked identical sequences, we introduced this locus into the Col background by genetic crosses. The inverted repeat induced de novo methylation of all three unmethylated Col PAI genes, with methylation efficiency varying with the position of the target locus. These results, plus results with inverted repeat transgenes, show that methylation is communicated by a DNA/DNA pairing mechanism.