bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultra Small-Mass Graphitization by Sealed Tube Zinc Reduction Method for AMS 14C Measurements
Authors: Xu Xiaomei , Gao Pan , Salamanca Eric G
Published: January 2017

A modified sealed tube Zn reduction method based on Khosh et al. (2010) has been developed to graphitize ultra small-mass samples ranging from 4–15 μg carbon (C) for accelerator mass spectrometry (AMS) radiocarbon measurements. In this method, the reagent TiH2 is removed from the previous method while the amounts of Zn and Fe powder remain the same. The volume of the sealed reactor is further reduced by ∼40% to ∼0.75 cm3 and the graphitization temperature is lowered to 450 °C. Graphite targets produced by this method generally yield 12C+1 currents of about 0.5 μA per 1 μg C, similar to the small mass (15–100 μg C) sealed tube Zn reduction method previously reported by Khosh et al. (2010) when measured on the same AMS system at KCCAMS, University of California, Irvine. Change of Fe powder to Sigma-Aldrich (400-mesh) has yielded further improved backgrounds over Fe powder of Alfa Aesar (325-mesh). Modern C background from combustion and graphitization is estimated to be 0.2–0.8 μg C, and dead-C background to be 0.1–0.4 μg C. The accuracy and precision of ultra small-mass samples prepared by this method are size and 14C content dependent, but is usually ±4–5% for the smallest sample size of ∼4–5 μg C with modern 14C content. AMS on-line δ13C measurement that allows for correction of both graphitization and machine-induced isotopic fractionation is the key for applying the sealed tube Zn reduction method to ultra small-mass sample graphitization.
Status Report of the New AMS 14C Sample Preparation Lab of the Hertelendi Laboratory of Environmental Studies (Debrecen, Hungary)
Authors: Molnár M , Janovics R , Major I , Orsovszki J , Gönczi R , Veres M , Leonard A G , Castle S M , Lange T E , Wacker L , Hajdas I , Jull A J T
Published: January 2017

We document chemical laboratory procedures and results on international comparison samples at the Hertelendi Laboratory of Environmental Studies, Debrecen, Hungary. We also show results using the new MICADAS system and compare these results to internationally recognized standards and blank materials. The newly developed sample preparation system in HEKAL can handle samples as 1) organic material, 2) cellulose fraction of plant, 3) bones, 4) carbonate and shell, and 5) dissolved inorganic carbon of groundwater. The results of radiocarbon measurements on intercomparison samples confirm the reliability of the sample preparation system at HEKAL Lab and also the good performance of the MICADAS 14C system. The blank levels for each type of sample of 1 mg C carbon content are well reproducible, ∼0.3–0.5 pMC.
Contemporary Fraction of bis(2–ethylhexyl) Phthalate in Stilton Cheese by Accelerator Mass Spectrometry
Authors: Nelson Michael A , Ondov John M , VanDerveer Michael C , Buchholz Bruce A
Published: January 2017

Measurements of the radiocarbon abundance in 5 samples of bis(2–ethylhexyl) phthalate (DEHP) isolated from Stilton cheese were made by accelerator mass spectrometry (AMS) to determine the fraction of carbon originating from contemporary biogenic sources. DEHP is classified as a “priority hazardous substance” by the European Union, a probable human carcinogen by the United States Environmental Protection Agency, and is suspected to be a human endocrine disrupter. Measurement of its14C abundance in a specific food indicates whether its presence is due to contamination from industrially synthesized DEHP or a naturally inherent component. A method was developed to determine the contemporary carbon fraction of DEHP in a fatty food matrix at concentrations of 0.14 mg/kg. Five 90–μg quantities of DEHP were extracted from 12 kg of Stilton cheese and isolated by silica gel, size exclusion, and high-performance liquid chromatography (HPLC). Masses of samples were determined by gas chromatography mass spectrometry (GC-MS) analyses prior to combustion and manometry afterwards. The purity of DEHP carbon mass in each isolate was determined by multivariate deconvolution of GCMS fragmentation spectra obtained from measurements of standards and isolates, and ranged from 88.0 ± 1.8% to 92.3 ± 1.1% (n= 5, 1σ). Concurrently processed isolation method blanks contained from 0.15 ± 0.04 to 1.52 ± 0.06 μg (n= 3, 1σ) DEHP per sample and significant quantities of pre- and post-chromatographic extraneous carbon contamination. The mean14C-corrected contemporary carbon fraction of DEHP in the isolates was 0.235 ± 0.073 (1σ; and ± 0.091 at the 95% confidence level), revealing that the majority of DEHP in Stilton cheese results from anthropogenic sources, but with a significant naturally occurring component.
Modeling the Age of the Cape Riva (Y-2) Tephra
Authors: Lee Sharen , Ramsey Christopher Bronk , Hardiman Mark
Published: January 2017

Tephra from the Cape Riva (Y-2) eruption of Santorini has been found across the eastern Mediterranean. It presents an important link between marine and terrestrial records. A Poisson process (P Sequence) age-depth prior, with model averaging, is used to model individual previously published radiocarbon sequences, cross-linked with an exponential phase model parameter to obtain a robust age. Multiple sequences and 14C determinations from 3 eastern Mediterranean data sets (Seymour et al. 2004; Margari et al. 2009; Müller et al. 2011; Roeser et al. 2012) are used in the model. The modeled age of the Y-2 tephra produced within this study is 22,329–21,088 cal BP at 95.4% probability.
Radiocarbon Impact on a Nearby Tree of a Light-Water VVER-Type Nuclear Power Plant, Paks, Hungary
Authors: Janovics R , Kern Z , Güttler D , Wacker L , Barnabás I , Molnár M
Published: January 2017

Tree-ring series were collected for radiocarbon analyses from the vicinity of Paks nuclear power plant (NPP) and a background area (Dunaföldvár) for a 10-yr period (2000–2009). Samples of holocellulose were prepared from the wood and converted to graphite for accelerator mass spectrometry (AMS) 14C measurement using the MICADAS at ETH Zürich. The 14C concentration data from these tree rings was compared to the background tree rings for each year. The global decreasing trend of atmospheric 14C activity concentration was observed in the annual tree rings both in the background area and in the area of the NPP. As an average of the past 10 yr, the excess 14C emitted by the pressurized-water reactor (PWR) NPP to the atmosphere shows only a slight systematic excess (∼6′) 14C in the annual rings. The highest 14C excess was 13′ (in 2006); however, years with the same 14C level as the background were quite frequent in the tree-ring series.
Potential Influence of Diet on Bomb-Pulse Dating of Human Plaque Samples
Authors: Georgiadou Elisavet Andersson , Gonçalves Isabel , Uvo Cintia Bertacchi , Nilsson Jan , Skog Göran , Mattsson Sören , Pedro Luis M , Fernandes José Fernandes e , Stenström Kristina Eriksson
Published: January 2017

The radiocarbon concentration of different atherosclerotic plaque fragments obtained from 20 patients in Portugal, operated in 2000–2001, has been measured in order to define the year of plaque formation. A difference of 1.8–15 yr was observed, with the mean and median both 9 yr, between the bomb-pulse date estimated with the CALIBomb software and the operation date. Stable isotope (δ13C and δ15N) analysis was also performed and provides insight to the diet of the subjects. The wide range of measured stable isotope values could indicate that the subjects' diet varied, including an abundance of marine foodstuffs. It could also mean a different isotope fractionation process for the different plaque fragments (cap, core, interface to media) and a possible difference in tissues in which the various fragments are formed. Analysis of δ13C and δ15N values of each patient separately revealed subjects considered more influenced by marine foodstuffs consumption.
Depositional Processes of Organic Matter in the Rhône River Delta (Gulf of Lions, France) Traced by Density Fractionation Coupled with Δ14C and δ13C
Authors: Toussaint Flora , Tisnérat-Laborde Nadine , Cathalot Cécile , Buscail Roselyne , Kerhervé Philippe , Rabouille Christophe
Published: January 2017

As a main source of freshwater and particles, the Rhône River plays a major role in the biogeochemical cycle of organic carbon (OC) in the Mediterranean Sea. To better understand the origin of organic matter and the processes leading to its export to the coastal sea near the Rhône River, we measured radiocarbon (Δ14C) and stable carbon isotopes (δ13C) in the sediments of the delta, after density fractionation. In April 2007, 3 sites located along an offshore transect (A, C, and E) were sampled for surface sediments, and bulk sediment was separated into 4 fractions of different densities (<1.6, 1.6–2, 2–2.5, and >2.5 g cm−3). In order to better understand the evolution of the OC along the transect, we investigated the OC sources and their evolution for each density fraction. Bulk OC shows a large increase in δ13C from −27.2′ nearshore to −24.5′ at offshore stations while Δ14C decreased from 59′ to −320′. The distribution of δ13C with density displayed a convex pattern at all stations. Except for fraction >2.5 g cm−3, δ13C increases by 2.5′ between stations A and E, indicating a loss of terrestrial signature. The distribution of Δ14C versus density had a concave pattern at all stations: at a single station, it showed a large heterogeneity with a difference of 500–600′ between the <1.6 and 2–2.5 g cm−3 fractions. A decrease in Δ14C of −400′ among the different density fractions was observed along the offshore transect. The density fraction >2.5 g cm−3 had less variability, with an average δ13C of −24.6 ± 0.4′ and Δ14C of −370 ± 115′. Several processes may explain this distribution: retention in the prodelta of large particles; mineralization of all fractions during the transport and deposition in the delta and shelf sediments; and dilution of terrestrial particles in continental shelf pool.
Variation of Δ14C and δ13C Values of Dissolved Humic and Fulvic Acids in the Tokachi River System in Northern Japan
Authors: Nagao Seiya , Aramaki Takafumi , Fujitake Nobuhide , Kodama Hiroki , Tanaka Takayuki , Ochiai Shinya , Uchida Masao , Shibata Yasuyuki , Yamamoto Masayoshi
Published: January 2017

Characteristics of dissolved humic and fulvic acids in river waters were studied during 2003–2005 at 4 sites located in the headwaters and in the upper and lower Tokachi River, including a lowland tributary site. Fulvic acids from the headwaters to downstream areas have similar elemental composition and 13C-NMR spectra. Humic acids have similar characteristics in the Tokachi River system. In contrast, δ13C and Δ14C values exhibit a decreasing trend from the upper to the lower and tributary sites, although the headwater site has heavier δ13C and lower Δ14C values than the upper site. Fulvic acids had similar δ13C values from the upper to lower sites, but 123′ higher in Δ14C than those of humic acids on average. The δ13C and Δ14C values exhibited differences in downward variation for humic and fulvic acids. In the Tokachi River system, these results suggest that differences in transport pathways and residence times of humic and fulvic acids reflect differences in the δ13C and Δ14C values in a single river basin.
Development of a Line for Dissolved Inorganic Carbon Extraction at LMC14 Artemis Laboratory in Saclay, France
Authors: Dumoulin J P , Caffy I , Comby-Zerbino C , Delqué-Količ E , Hain S , Massault M , Moreau C , Quiles A , Setti V , Souprayen C , Tannau J-F , Thellier B , Vincent J
Published: January 2017

We present here the new line installed at the LMC14 laboratory (Saclay, France) for dissolved inorganic carbon (DIC) extraction from marine and freshwater samples. The operating system and extraction process are described. The efficiency of the line design was checked, and the background (0.42 ± 0.11 pMC) and the reproducibility on artificial samples obtained by dissolution of IAEA-C1, IAEA-C2, and commercial bicarbonate in water were evaluated. An intercomparison with an independent lab (IDES) was also carried out on a natural sample. The line processes 3 samples a day under a helium flow and is able to run samples up to 40,000 ka.
Synthetic Constraint of Soil C Dynamics Using 50 Years of 14C and Net Primary Production (NPP) in a New Zealand Grassland Site
Authors: Troy Baisden W , Keller E D
Published: January 2017

Time-series radiocarbon measurements have substantial ability to constrain the size and residence time of the soil C pools commonly represented in ecosystem models. 14C remains unique in its ability to constrain the size and turnover rate of the large stabilized soil C pool with roughly decadal residence times. The Judgeford soil, near Wellington, New Zealand, provides a detailed 11-point 14C time series enabling observation of the incorporation and loss of bomb 14C in surface soil from 1959–2002. Calculations of the flow of C through the plant-soil system can be improved further by combining the known constraints of net primary productivity (NPP) and 14C-derived C turnover. We show the Biome-BGC model provides good estimates of NPP for the Judgeford site and estimates NPP from 1956–2010. Synthesis of NPP and 14C data allows parameters associated with the rapid turnover “active” soil C pool to be estimated. This step is important because it demonstrates that NPP and 14C can provide full data-based constraint of pool sizes and turnover rates for the 3 pools of soil C used in nearly all ecosystem and global C-cycle models.
GANEing traction: The broad applicability of NE hotspots to diverse cognitive and arousal phenomena
Authors: Mather Mara , Clewett David , Sakaki Michiko , Harley Carolyn W.
Published: January 2017

The GANE (glutamate amplifies noradrenergic effects) model proposes that local glutamate–norepinephrine interactions enable “winner-take-more” effects in perception and memory under arousal. A diverse range of commentaries addressed both the nature of this “hotspot” feedback mechanism and its implications in a variety of psychological domains, inspiring exciting avenues for future research.
Sex differences in early-life programming of the hypothalamic–pituitary–adrenal axis in humans suggest increased vulnerability in females: a systematic review
Authors: Carpenter T. , Grecian S. M. , Reynolds R. M.
Published: January 2017

Fetal glucocorticoid overexposure is a key mechanism linking early development with later-life disease. In humans, low birth weight associates with increased fasting cortisol, hypothalamic–pituitary–adrenal (HPA) axis reactivity, and with cardiovascular risk and cognitive decline. As there are sex differences in these adult diseases, we hypothesized that there may be sex differences in programming of the HPA axis in response to prenatal stressors. We conducted a systematic review following Meta-Analysis of Observational Studies in Epidemiology and Preferred Reporting Items for Systematic Reviews and Meta-Analysis. We searched Embase, MEDLINE and Web of Science from inception to 31 October 2016. We included studies related to sex differences, prenatal exposures and HPA axis. We excluded studies investigating specific disease states. The 23 included studies investigated the consequences of low birth weight, preterm birth and maternal stressors of asthma, psychosocial stress and glucocorticoid medications on HPA axis outcomes of placental glucocorticoid biology and offspring HPA axis function in early life and later life. Female offspring exposed to stressors had increased HPA axis reactivity compared with males. Furthermore, the female placenta increased its permeability to maternal glucocorticoids following maternal stress with changes in the expression of 11β-hydroxysteroid dehydrogenase enzymes in response to maternal glucocorticoid exposure or asthma. Among males there was some evidence of altered diurnal cortisol secretion. We conclude that although there is some evidence of male vulnerability leading to altered diurnal cortisol secretion, the female HPA axis is more vulnerable to programming, particularly in terms of its reactivity; this suggests a mechanism underlying sex differences in later-life diseases.
Associations Between Obesity Indicators and Blood Pressure in Chinese Adult Twins
Authors: Liao Chunxiao , Gao Wenjing , Cao Weihua , Lv Jun , Yu Canqing , Wang Shengfeng , Zhao Qian , Pang Zengchang , Cong Liming , Wang Hua , Wu Xianping , Li Liming
Published: January 2017

Obesity is associated with blood pressure (BP), but the associations between different obesity indicators and BP have not reached agreement. Besides, both obesity and BP are influenced by genetic and environmental factors. Whether they share the same genetic or environmental etiology has not been fully understood. We therefore analyzed the relationship between different obesity indicators and BP components as well as the genetic and environmental contributions to these relationships in a Chinese adult twin sample. Twins aged 18–79 years (n = 941) were included in this study. Body mass index (BMI) was used as the index of general obesity, whereas waist circumference (WC), waist-to-height ratio (WHtR), and waist-to-hip ratio (WHR) were used as the indicators of central obesity. BP components included systolic blood pressure (SBP) and diastolic blood pressure (DBP). Linear regression models and bivariate structural equation models were used to examine the relation of various obesity indicators with BP components, and genetic or environmental influences on these associations, respectively. A strong association of BP components with BMI—and a somewhat weaker association with WC, WHtR, and WHR—was found in both sexes, independent of familial factors. Of these phenotypic correlations between obesity indicators and BP components, 60–76% were attributed to genetic factors, whereas 24–40% were attributed to unique environmental factors. General obesity was most strongly associated with high BP in Chinese adult twins. There were common genetic backgrounds for obesity and BP, and unique environmental factors also played a role.
Genetic and Environmental Influences on Pulmonary Function and Muscle Strength: The Chinese Twin Study of Aging
Authors: Tian Xiaocao , Xu Chunsheng , Wu Yili , Sun Jianping , Duan Haiping , Zhang Dongfeng , Jiang Baofa , Pang Zengchang , Li Shuxia , Tan Qihua
Published: January 2017

Genetic and environmental influences on predictors of decline in daily functioning, including forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), handgrip, and five-times-sit-to-stand test (FTSST), have not been addressed in the aging Chinese population. We performed classical twin modeling on FEV1, FVC, handgrip, and FTSST in 379 twin pairs (240 MZ and 139 DZ) with median age of 50 years (40–80 years). Data were analyzed by fitting univariate and bivariate twin models to estimate the genetic and environmental influences on these measures of physical function. Heritability was moderate for FEV1, handgrip, and FTSST (55–60%) but insignificant for FVC. Only FVC showed moderate control, with shared environmental factors accounting for about 50% of the total variance. In contrast, all measures of pulmonary function and muscle strength showed modest influences from the unique environment (40–50%). Bivariate analysis showed highly positive genetic correlations between FEV1 and FVC (rG = 1.00), and moderately negative genetic correlations between FTSST and FEV1 (rG = −0.33) and FVC (rG = −0.42). FEV1 and FVC, as well as FEV1 and handgrip, displayed high common environmental correlations (rC = 1.00), and there were moderate correlations between FVC and handgrip (rC = 0.44). FEV1 and FVC showed high unique environmental correlations (rE = 0.76) and low correlations between handgrip and FEV1 (rE = 0.17), FVC (rE = 0.14), and FTSST (rE = −0.13) with positive or negative direction. We conclude that genetic factors contribute significantly to the individual differences in common indicators of daily functioning (FEV1, handgrip, and FTSST). FEV1 and FVC were genetically and environmentally correlated. Pulmonary function and FTSST may share similar sets of genes but in the negative direction. Pulmonary function and muscle strength may have a shared environmental background.
Bullying and Victimization: The Effect of Close Companionship
Authors: Veldkamp Sabine A. M. , van Bergen Elsje , de Zeeuw Eveline L. , van Beijsterveldt Catharina E. M. , Boomsma Dorret I. , Bartels Meike
Published: January 2017

Peer bullying and victimization are a widespread phenomenon among school-age children and can have detrimental effects on the development of children. To examine whether having a close companion during childhood increases or decreases risk of victimization and bullying, this study compared twins to singleton children. A large group of twins (n = 9,909) were included who were compared to their related non-twin siblings (n = 1,534) aged 7–12 from the Netherlands Twin Register, thus creating optimal matching between twins and non-twins. Bullying and victimization were each based on a four-item scale filled out by their teachers. Prevalence rates for either bullying or victimization did not differ between twins and singletons. In total, in the past couple of months, 36% of children bullied peers moderately to severely, and 35% suffered moderately to severely from victimization. Boys were more likely to bully and were more prone to becoming a victim than girls. The most notable finding is that female twin pairs placed together in the same classroom did not bully more often, but were victimized less often, thus pointing to a protective effect of having a close companion in the classroom.
Bacterial morphotype grading for periodontal disease assessment
Authors: Smeda-Pienaar Kim , Kaambo Eveline , Africa Charlene W J
Published: January 2017

Background:

Listgarten and Hellden (1978) used darkfield microscopy of wet mounts to differentiate between healthy and periodontally diseased sites in the mouth by expressing the different bacterial morphotypes observed as a percentage of the total number of bacteria counted. This method of periodontal disease assessment gained favour as a diagnostic tool but presented with the limitation of immediate examination to determine the number of motile rods present and an inability to distinguish between gingivitis and periodontitis. Grading of bacterial morphotypes into several distinct categories of health or disease (Ison and Hay, 2002), simplified the scoring system of Gram-stained smears for the diagnosis of bacterial vaginosis (Nugent et al. 1991). The application of a similar grading system using stained smears rather than wet mounts could be advantageous to the diagnosis of periodontal disease.

Objectives/aims:

This study tested the hypothesis that stained smears of dental plaque collected from the gingival crevice of individuals with varying probing pocket depths (PD) may provide a grading system for periodontal disease assessment.

Materials and methods:

Subgingival plaque samples were collected from 49 patients, stained with a silver stain and the proportions of each bacterial morphotype graded relative to their respective PD measurements.

Results:

This technique allowed for a grading system of I–IV, with grade I indicating health and grade IV indicating severe periodontal disease.

Discussion:

Stained smear examination eliminates the time restriction for motile rod enumeration and allows for storage of smears for future reference.

Conclusion:

Standardization of the microscopic areas to be evaluated or examined will facilitate the agreement of cut-off values for the diagnosis of periodontal disease.
Exosome-derived microRNAs in cancer metabolism: possible implications in cancer diagnostics and therapy
Authors: Tomasetti Marco , Lee Wan , Santarelli Lory , Neuzil Jiri
Published: January 2017

Malignant progression is greatly affected by dynamic cross-talk between stromal and cancer cells. Exosomes are secreted nanovesicles that have key roles in cell–cell communication by transferring nucleic acids and proteins to target cells and tissues. Recently, MicroRNAs (miRs) and their delivery in exosomes have been implicated in physiological and pathological processes. Tumor-delivered miRs, interacting with stromal cells in the tumor microenvironment, modulate tumor progression, angiogenesis, metastasis and immune escape. Altered cell metabolism is one of the hallmarks of cancer. A number of different types of tumor rely on mitochondrial metabolism by triggering adaptive mechanisms to optimize their oxidative phosphorylation in relation to their substrate supply and energy demands. Exogenous exosomes can induce metabolic reprogramming by restoring the respiration of cancer cells and supress tumor growth. The exosomal miRs involved in the modulation of cancer metabolism may be potentially utilized for better diagnostics and therapy.
Improper electric polarization in simple perovskite oxides with two magnetic sublattices
Authors: Zhao Hong Jian , Bellaiche L. , Chen Xiang Ming , Íñiguez Jorge
Published: January 2017

ABO3 perovskite oxides with magnetic A and B cations offer a unique playground to explore interactions involving two spin sublattices and the emergent effects they may drive. Of particular interest is the possibility of having magnetically driven improper ferroelectricity, as in the much studied families of rare-earth orthoferrites and orthochromites; yet, the mechanisms behind such effects remain to be understood in detail. Here we show that the strongest polar order corresponds to collinear spin configurations and is driven by non-relativistic exchange-strictive mechanisms. Our first-principles simulations reveal the dominant magnetostructural couplings underlying the observed ferroelectricity, including a striking magnetically driven piezoelectric effect. Further, we derive phenomenological and atomistic theories that describe such couplings in a generic perovskite lattice. This allows us to predict how the observed effects can be enhanced, and even how similar ones can be obtained in other perovskite families.
Humans rather than climate the primary cause of Pleistocene megafaunal extinction in Australia
Authors: van der Kaars Sander , Miller Gifford H. , Turney Chris S. M. , Cook Ellyn J. , Nürnberg Dirk , Schönfeld Joachim , Kershaw A. Peter , Lehman Scott J.
Published: January 2017

Environmental histories that span the last full glacial cycle and are representative of regional change in Australia are scarce, hampering assessment of environmental change preceding and concurrent with human dispersal on the continent ca. 47,000 years ago. Here we present a continuous 150,000-year record offshore south-western Australia and identify the timing of two critical late Pleistocene events: wide-scale ecosystem change and regional megafaunal population collapse. We establish that substantial changes in vegetation and fire regime occurred ∼70,000 years ago under a climate much drier than today. We record high levels of the dung fungus Sporormiella, a proxy for herbivore biomass, from 150,000 to 45,000 years ago, then a marked decline indicating megafaunal population collapse, from 45,000 to 43,100 years ago, placing the extinctions within 4,000 years of human dispersal across Australia. These findings rule out climate change, and implicate humans, as the primary extinction cause.
Anthropogenic ecosystem disturbance and the recovery debt
Authors: Moreno-Mateos David , Barbier Edward B. , Jones Peter C. , Jones Holly P. , Aronson James , López-López José A. , McCrackin Michelle L. , Meli Paula , Montoya Daniel , Rey Benayas José M.
Published: January 2017

Ecosystem recovery from anthropogenic disturbances, either without human intervention or assisted by ecological restoration, is increasingly occurring worldwide. As ecosystems progress through recovery, it is important to estimate any resulting deficit in biodiversity and functions. Here we use data from 3,035 sampling plots worldwide, to quantify the interim reduction of biodiversity and functions occurring during the recovery process (that is, the ‘recovery debt’). Compared with reference levels, recovering ecosystems run annual deficits of 46–51% for organism abundance, 27–33% for species diversity, 32–42% for carbon cycling and 31–41% for nitrogen cycling. Our results are consistent across biomes but not across degrading factors. Our results suggest that recovering and restored ecosystems have less abundance, diversity and cycling of carbon and nitrogen than ‘undisturbed’ ecosystems, and that even if complete recovery is reached, an interim recovery debt will accumulate. Under such circumstances, increasing the quantity of less-functional ecosystems through ecological restoration and offsetting are inadequate alternatives to ecosystem protection.
The paradoxical functions of EGFR during breast cancer progression
Authors: Ali Remah , Wendt Michael K
Published: January 2017

The epidermal growth factor receptor (EGFR) is one of the most well-studied signaling pathways in cancer progression. As a result, numerous therapeutics including small-molecule inhibitors and monoclonal antibodies have been developed to target this critical oncogenic driver. Several of these EGFR inhibitors (EGFRi) have been evaluated in metastatic breast cancer, as high-level EGFR expression in primary tumors correlates with the highly aggressive basal-like phenotype and predicts for poor patient prognosis. Surprisingly, these trials have been unanimously unsuccessful at improving patient outcomes. Numerous factors, such as lack of proper patient selection may have contributed to the failure of these trials. However, recent findings suggest that there are fundamental changes in EGFR signaling that take place during primary tumor invasion, dissemination and ultimate metastasis of breast cancer cells. Herein, we review the outcomes of EGFR-targeted clinical trials in breast cancer and explore our current understanding of EGFR signaling within primary mammary tumors and how these events are altered in the metastatic setting. Overall, we put forth the hypothesis that fundamental changes in EGFR signaling between primary and metastatic tumors, a process we term the ‘EGFR paradox,’ contribute to the clinically observed inherent resistance to EGFRi. Furthermore, this hypothesis introduces the possibility of utilizing EGFR agonism as a potential therapeutic approach for the treatment of metastatic breast cancer.
Simulating the hydrologic cycle in coal mining subsidence areas with a distributed hydrologic model
Authors: Wang Jianhua , Lu Chuiyu , Sun Qingyan , Xiao Weihua , Cao Guoliang , Li Hui , Yan Lingjia , Zhang Bo
Published: January 2017

Large-scale ground subsidence caused by coal mining and subsequent water-filling leads to serious environmental problems and economic losses, especially in plains with a high phreatic water level. Clarifying the hydrologic cycle in subsidence areas has important practical value for environmental remediation, and provides a scientific basis for water resource development and utilisation of the subsidence areas. Here we present a simulation approach to describe interactions between subsidence area water (SW) and several hydrologic factors from the River-Subsidence-Groundwater Model (RSGM), which is developed based on the distributed hydrologic model. Analysis of water balance shows that the recharge of SW from groundwater only accounts for a small fraction of the total water source, due to weak groundwater flow in the plain. The interaction between SW and groundwater has an obvious annual cycle. The SW basically performs as a net source of groundwater in the wet season, and a net sink for groundwater in the dry season. The results show there is an average 905.34 million m3 per year of water available through the Huainan coal mining subsidence areas (HCMSs). If these subsidence areas can be integrated into water resource planning, the increasingly precarious water supply infrastructure will be strengthened.
Investigation of changes in structure and thermodynamic of spruce budworm antifreeze protein under subfreezing temperature
Authors: Nguyen Hung , Le Ly
Published: January 2017

The aim of this theoretical work is to investigate of the changes in structure and thermodynamics of spruce budworm antifreeze protein (sbAFP) at low temperatures by using molecular dynamics simulation. The aqueous solution will form ice crystal network under the vaguely hexagonal shape at low temperature and fully represented the characteristics of hydrophobic interaction. Like ice crystal network, the cyclohexane region (including cyclohexane molecules) have enough of the characteristics of hydrophobic interaction. Therefore, in this research the cyclohexane region will be used as a representation of ice crystal network to investigate the interactions of sbAFP and ice crystal network at low temperature. The activity of sbAFP in subfreezing environment, therefore, can be clearly observed via the changes of the hydrophobic (cyclohexane region) and hydrophilic (water region) interactions. The obtained results from total energies, hydrogen bond lifetime correlation C(t), radial distribution function, mean square deviation and snapshots of sbAFP complexes indicated that sbAFP has some special changes in structure and interaction with water and cyclohexane regions at 278 K, as being transition temperature point of water molecules in sbAFP complex at low temperatures, which is more structured and support the experimental observation that the sbAFP complex becomes more rigid as the temperature is lowered.
Spectroscopic evidence of odd frequency superconducting order
Authors: Pal Avradeep , Ouassou J. A. , Eschrig M. , Linder J. , Blamire M. G.
Published: January 2017

Spin filter superconducting S/I/N tunnel junctions (NbN/GdN/TiN) show a robust and pronounced Zero Bias Conductance Peak (ZBCP) at low temperatures, the magnitude of which is several times the normal state conductance of the junction. Such a conductance anomaly is representative of unconventional superconductivity and is interpreted as a direct signature of an odd frequency superconducting order.
BabA dependent binding of Helicobacter pylori to human gastric mucins cause aggregation that inhibits proliferation and is regulated via ArsS
Authors: Skoog Emma C. , Padra Médea , Åberg Anna , Gideonsson Pär , Obi Ikenna , Quintana-Hayashi Macarena P. , Arnqvist Anna , Lindén Sara K.
Published: January 2017

Mucins in the gastric mucus layer carry a range of glycan structures, which vary between individuals, can have antimicrobial effect or act as ligands for Helicobacter pylori. Mucins from various individuals and disease states modulate H. pylori proliferation and adhesin gene expression differently. Here we investigate the relationship between adhesin mediated binding, aggregation, proliferation and adhesin gene expression using human gastric mucins and synthetic adhesin ligand conjugates. By combining measurements of optical density, bacterial metabolic activity and live/dead stains, we could distinguish bacterial aggregation from viability changes, enabling elucidation of mechanisms behind the anti-prolific effects that mucins can have. Binding of H. pylori to Leb-glycoconjugates inhibited the proliferation of the bacteria in a BabA dependent manner, similarly to the effect of mucins carrying Leb. Furthermore, deletion of arsS lead to a decrease in binding to Leb-glycoconjugates and Leb-decorated mucins, accompanied by decreased aggregation and absence of anti-prolific effect of mucins and Leb-glycoconjugates. Inhibition of proliferation caused by adhesin dependent binding to mucins, and the subsequent aggregation suggests a new role of mucins in the host defense against H. pylori. This aggregating trait of mucins may be useful to incorporate into the design of adhesin inhibitors and other disease intervention molecules.
Effects of climatic variables on weight loss: a global analysis
Authors: Ustulin Morena , Keum Changwon , Woo Junghoon , Woo Jeong-taek , Rhee Sang Youl
Published: January 2017

Several studies have analyzed the effects of weather on factors associated with weight loss. In this study, we directly analyzed the effect of weather on intentional weight loss using global-scale data provided by smartphone applications. Through Weather Underground API and the Noom Coach application, we extracted information on weather and body weight for each user located in each of several geographic areas on all login days. We identified meteorological information (pressure, precipitation, wind speed, dew point, and temperature) and self-monitored body weight data simultaneously. A linear mixed-effects model was performed analyzing 3274 subjects. Subjects in North America had higher initial BMIs than those of subjects in Eastern Asia. During the study period, most subjects who used the smartphone application experienced weight loss in a significant way (80.39%, p-value < 0.001). Subjects who infrequently recorded information about dinner had smaller variations than those of other subjects (βfreq.users dinner*time = 0.007, p-value < 0.001). Colder temperature, lower dew point, and higher values for wind speed and precipitation were significantly associated with weight loss. In conclusion, we found a direct and independent impact of meteorological conditions on intentional weight loss efforts on a global scale (not only on a local level).
Asymmetric Waveforms Decrease Lethal Thresholds in High Frequency Irreversible Electroporation Therapies
Authors: Sano Michael B. , Fan Richard E. , Xing Lei
Published: January 2017

Irreversible electroporation (IRE) is a promising non-thermal treatment for inoperable tumors which uses short (50–100 μs) high voltage monopolar pulses to disrupt the membranes of cells within a well-defined volume. Challenges with IRE include complex treatment planning and the induction of intense muscle contractions. High frequency IRE (H-FIRE) uses bursts of ultrashort (0.25–5 μs) alternating polarity pulses to produce more predictable ablations and alleviate muscle contractions associated with IRE. However, H-FIRE generally ablates smaller volumes of tissue than IRE. This study shows that asymmetric H-FIRE waveforms can be used to create ablation volumes equivalent to standard IRE treatments. Lethal thresholds (LT) of 505 V/cm and 1316 V/cm were found for brain cancer cells when 100 μs IRE and 2 μs symmetric H-FIRE waveforms were used. In contrast, LT as low as 536 V/cm were found for 2 μs asymmetric H-FIRE waveforms. Reversible electroporation thresholds were 54% lower than LTs for symmetric waveforms and 33% lower for asymmetric waveforms indicating that waveform symmetry can be used to tune the relative sizes of reversible and irreversible ablation zones. Numerical simulations predicted that asymmetric H-FIRE waveforms are capable of producing ablation volumes which were 5.8–6.3x larger than symmetric H-FIRE waveforms indicating that in vivo investigation of asymmetric waveforms is warranted.
Identification of novel cellular clusters define a specialized area in the cerebellar periventricular zone
Authors: González-González María Alejandra , Gómez-González Gabriela B. , Becerra-González Marymar , Martínez-Torres Ataúlfo
Published: January 2017

The periventricular zone of cerebellum is a germinative niche during the embryonic development, nevertheless its structural organization and functional implications in adult have not been widely studied. Here we disclose the presence of two novel clusters of cells in that area. The first one was named the subventricular cellular cluster (SVCC) and is composed of cells that express glial and neuronal markers. The second was named the ventromedial cord (VMC) and appears as a streak of biciliated cells with microvillosities facing the ventricle, that includes GFAP+ and nestin+ cells organized along the periventricular vasculature. The dorsal limit of the SVCC is associated with myelinated axons of neurons of unknown origin. This paper describes the characteristics and organization of these groups of cells. They can be observed from late embryonic development in the transgenic mouse line GFAP-GFP. The SVCC and VMC expand during early postnatal development but are restricted to the central area of the ventricle in adulthood. We did not find evidence of cell proliferation, cell migration or the presence of fenestrated blood vessels. These findings provide new insights into the knowledge of the cellular composition and structural organization of the periventricular zone of cerebellum.
Modification of tumour cell metabolism modulates sensitivity to Chk1 inhibitor-induced DNA damage
Authors: Massey Andrew J.
Published: January 2017

Chk1 kinase inhibitors are currently under clinical investigation as potentiators of cytotoxic chemotherapy and demonstrate potent activity in combination with anti-metabolite drugs that increase replication stress through the inhibition of nucleotide or deoxyribonucleotide biosynthesis. Inhibiting other metabolic pathways critical for the supply of building blocks necessary to support DNA replication may lead to increased DNA damage and synergy with an inhibitor of Chk1. A screen of small molecule metabolism modulators identified combinatorial activity between a Chk1 inhibitor and chloroquine or the LDHA/LDHB inhibitor GSK 2837808A. Compounds, such as 2-deoxyglucose or 6-aminonicotinamide, that reduced the fraction of cells undergoing active replication rendered tumour cells more resistant to Chk1 inhibitor-induced DNA damage. Withdrawal of glucose or glutamine induced G1 and G2/M arrest without increasing DNA damage and reduced Chk1 expression and activation through autophosphorylation. This suggests the expression and activation of Chk1 kinase is associated with cells undergoing active DNA replication. Glutamine starvation rendered tumour cells more resistant to Chk1 inhibitor-induced DNA damage and reversal of the glutamine starvation restored the sensitivity of tumour cells to Chk1 inhibitor-induced DNA damage. Chk1 inhibitors may be a potentially useful therapeutic treatment for patients whose tumours contain a high fraction of replicating cells.
Broadband and Broad-angle Polarization-independent Metasurface for Radar Cross Section Reduction
Authors: Sun Hengyi , Gu Changqing , Chen Xinlei , Li Zhuo , Liu Liangliang , Xu Bingzheng , Zhou Zicheng
Published: January 2017

In this work, a broadband and broad-angle polarization-independent random coding metasurface structure is proposed for radar cross section (RCS) reduction. An efficient genetic algorithm is utilized to obtain the optimal layout of the unit cells of the metasurface to get a uniform backscattering under normal incidence. Excellent agreement between the simulation and experimental results show that the proposed metasurface structure can significantly reduce the radar cross section more than 10 dB from 17 GHz to 42 GHz when the angle of incident waves varies from 10° to 50°. The proposed coding metasurface provides an efficient scheme to reduce the scattering of the electromagnetic waves.
Effect of thermal annealing Super Yellow emissive layer on efficiency of OLEDs
Authors: Burns Samantha , MacLeod Jennifer , Trang Do Thu , Sonar Prashant , Yambem Soniya D.
Published: January 2017

Thermal annealing of the emissive layer of an organic light emitting diode (OLED) is a common practice for solution processable emissive layers and reported annealing temperatures varies across a wide range of temperatures. We have investigated the influence of thermal annealing of the emissive layer at different temperatures on the performance of OLEDs. Solution processed polymer Super Yellow emissive layers were annealed at different temperatures and their performances were compared against OLEDs with a non-annealed emissive layer. We found a significant difference in the efficiency of OLEDs with different annealing temperatures. The external quantum efficiency (EQE) reached a maximum of 4.09% with the emissive layer annealed at 50 °C. The EQE dropped by ~35% (to 2.72%) for OLEDs with the emissive layers annealed at 200 °C. The observed performances of OLEDs were found to be closely related to thermal properties of polymer Super Yellow. The results reported here provide an important guideline for processing emissive layers and are significant for OLED and other organic electronics research communities.
Prediction of very late arrhythmia recurrence after radiofrequency catheter ablation of atrial fibrillation: The MB-LATER clinical score
Authors: Mujović Nebojša , Marinković Milan , Marković Nebojša , Shantsila Alena , Lip Gregory Y. H. , Potpara Tatjana S.
Published: January 2017

Reliable prediction of very late recurrence of atrial fibrillation (VLRAF) occuring >12 months after catheter ablation (CA) in apparently “cured” patients could optimize long-term follow-up and modify decision-making regarding the discontinuation of oral anticoagulant therapy. In a single-centre cohort of consecutive patients post radiofrequency AFCA, we retrospectively derived a novel score for VLRAF prediction. Of 133 consecutive post AFCA patients (mean age 56.9 ± 11.8 years, 63.9% male, 69.2% with paroxysmal AF) who were arrhythmia-free at 12 months (excluding 3-month “blanking period”), 20 patients expirienced a VLRAF during a 29.1 ± 10.1-month follow-up, with a 3-year cumulative VLRAF rate of 31.1%. The MB-LATER score (Male, Bundle brunch block, Left atrium ≥47 mm, Type of AF [paroxysmal, persistent or long-standing persistent], and ER-AF = early recurrent AF), had better predictive ability for VLRAF (AUC 0.782) than the APPLE, ALARMc, BASE-AF2, CHADS2, CHA2DS2VASc or HATCH score (AUC 0.716, 0.671, 0.648, 0.552, 0.519 and 0.583, respectively), resulted in an improved net reclassification index (NRI) of 48.6–95.1% and better identified patients with subsequent VLRAF using decision-curve analysis (DCA). The MB-LATER score provides a readily available VLRAF risk assessment, and performs better than other scores. Validation of the MB-LATER score in other cohorts is underway.
Sham Electroacupuncture Methods in Randomized Controlled Trials
Authors: Chen Zi-xian , Li Yan , Zhang Xiao-guang , Chen Shuang , Yang Wen-ting , Zheng Xia-wei , Zheng Guo-qing
Published: January 2017

Sham electroacupuncture (EA) control is commonly used to evaluate the specific effects of EA in randomized-controlled trials (RCTs). However, establishing an inert and concealable sham EA control remains methodologically challenging. Here, we aimed to systematically investigate the sham EA methods. Eight electronic databases were searched from their inception to April 2015. Ten out of the 17 sham EA methods were identified from 94 RCTs involving 6134 participants according to three aspects: needle location, depth of needle insertion and electrical stimulation. The top three most frequently used types were sham EA type A, type L and type O ordinally. Only 24 out of the 94 trials reported credibility tests in six types of sham EA methods and the results were mainly as follows: sham EA type A (10/24), type B (5/24) and type Q (5/24). Compared with sham EA controls, EA therapy in 56.2% trials reported the specific effects, of which the highest positive rate was observed in type N (3/4), type F (5/7), type D (4/6) and type M (2/3). In conclusion, several sham EA types were identified as a promising candidate for further application in RCTs. Nonetheless, more evidence for inert and concealable sham EA control methods is needed.