bluuebunny/crossref_metadata_2025_split huggingface dataset:
Model‐based description of indicator displacement assay sensor arrays for quantitation of mixtures
Authors: Rostami Akram , Karimvand Somaiyeh Khodadadi , Abdollahi Hamid 
Published: September 2019

AbstractThis paper propounds an approach for the simultaneous analysis of colorless analytes using optical sensor arrays. On the basis of the equilibrium law, the principles of indicator displacement assay (IDA)–based sensor arrays that can be utilized for the efficient quantification of analytes in the mixture solutions through multivariate hard modeling approach are discussed in detail. According to these principles, two different sensor array systems are designed for the simultaneous analysis of the analytes with nonselective signal in the mixtures. Each sensor element of the designed sensor arrays consists of a single indicator and receptor but has different equilibrium environmental conditions.Among all amino acids, only histidine and cysteine reveal significant responses to the Ni‐murexide IDA probe. So, in the first experiment, the Ni‐murexide IDA sensor arrays are applied for the precise and selective quantification of these two amino acids in the mixture solutions. The root mean square error of predictions (RMSEPs) of the prediction dataset obtained by the radial basis function–artificial neural network (RBF‐ANN) model are 3.41% and 4.72% for histidine and cysteine, respectively, in the unknown artificial mixtures. In the second experiment, two metal cations, namely, zinc and cadmium, are simultaneously quantified by another designed IDA‐based sensor array. The metallochromic indicator 4‐(2‐pyridylazo) resorcinol (PAR) is applied in two different equilibrium conditions for each sensor element. The results of predicting these two metals in the unknown mixtures via the RBF‐ANN model are 7.22% and 8.15% for zinc and cadmium, respectively.
Longitudinal monitoring of somatic genetic alterations in circulating cell‐free DNA during treatment with epidermal growth factor receptor–tyrosine kinase inhibitors
Authors: Iwama Eiji , Sakai Kazuko , Hidaka Noriko , Inoue Koji , Fujii Akiko , Nakagaki Noriaki , Ota Keiichi , Toyozawa Ryo , Azuma Koichi , Nakatomi Keita , Harada Taishi , Hisasue Junko , Sakata Shinya , Shimose Takayuki , Kishimoto Junji , Nakanishi Yoichi , Nishio Kazuto , Okamoto Isamu 
Published: September 2019

BackgroundThe aim of this study was to evaluate the potential of liquid biopsy for prediction of the efficacy of epidermal growth factor receptor (EGFR)–tyrosine kinase inhibitor (TKI) treatment and for assessment of the changes in genetic alterations during such treatment.MethodsPlasma samples were prospectively collected from non–small cell lung cancer patients with EGFR‐activating mutations during EGFR‐TKI treatment until disease progression and were analyzed for such mutations with droplet digital polymerase chain reaction and for other somatic alterations with next‐generation sequencing.ResultsOne hundred patients, including 87 who were EGFR‐TKI naïve, were enrolled. Median progression‐free survival was significantly shorter for EGFR‐TKI–naïve patients with EGFR‐activating mutations detected in plasma at baseline than for those without them (7.9 vs 19.0 months; P < .001), with the values being significantly longer for initially positive patients who became negative for these mutations at 12 or 24 weeks than for those who remained positive. An increase in the number of alleles positive for EGFR‐activating mutations in plasma during treatment was associated with disease progression, with a hazard ratio of 4.72 (95% CI, 2.07‐10.79; P < .001) for EGFR‐TKI–naïve patients showing an increase within 36 weeks. For 55 patients with available samples, the total number of somatic alterations (other than activating mutations or T790M of EGFR) in plasma was higher at disease progression than at baseline (33 vs 19; P = 0.04).ConclusionLiquid biopsy shows potential for prediction of EGFR‐TKI efficacy and elucidation of clonal tumor evolution during targeted therapy.
Inclusiveness and ethical considerations for observational, translational, and clinical cancer health disparity research
Authors: Behring Michael , Hale Kevin , Ozaydin Bunyamin , Grizzle William E. , Sodeke Stephen O. , Manne Upender 
Published: September 2019

BackgroundAlthough general trends in cancer outcomes are improving, racial/ethnic disparities in patient outcomes continue to widen, suggesting disparity‐related shortcomings in cancer research designs.MethodsUsing convenience sampling, a total of 24 data sources, representing several research designs and 5 high‐burden tumor types, were included for analyses. The percentages of races/ethnicities across each design/tumor type were compared with those of the 2017 US Census data. The authors used a framework based on the Belmont principles to evaluate the ethical strengths and/or weaknesses of each design.ResultsIn all designs, white individuals were found to be overrepresented. African American and Asian individuals were underrepresented, and Native Americans had consistently poor or no representation. In general, ethical concerns varied according to the study design. Clinical trials were high with regard to respect for persons and beneficence but low for equitable subject selection related to the inclusion of race/ethnicity. Observational study designs were more inclusive for race/ethnicity compared with clinical and translational studies, but their clinical usefulness was less.ConclusionsThe authors proposed that ethical concerns should vary according to the study design. Because observational designs have strengths in inclusiveness for race/ethnicity, their clinical usefulness can be improved by extending the Learning Health System in hospital catchment populations, the use of health records linked to biospecimens, and minority oversampling. Likewise, minority enrollment into clinical trials can be improved through Learning Health System linking and by using National Cancer Institute–mandated Community Outreach and Engagement Cores. This will allow precision medicine for otherwise overlooked minority subgroups.
Coupled sensory interneurons mediate escape neural circuit processing in an aquatic annelid worm, Lumbriculus variegatus
Authors: Lybrand Zane R. , Martinez‐Acosta Veronica G. , Zoran Mark J. 
Published: September 2019

AbstractThe interneurons associated with rapid escape circuits are adapted for fast pathway activation and rapid conduction. An essential aspect of fast activation is the processing of sensory information with limited delays. Although aquatic annelid worms have some of the fastest escape responses in nature, the sensory networks that mediate their escape behavior are not well defined. Here, we demonstrate that the escape circuit of the mud worm, Lumbriculus variegatus, is a segmentally arranged network of sensory interneurons electrically coupled to the central medial giant fiber (MGF), the command‐like interneuron for head withdrawal. Electrical stimulation of the body wall evoked fast, short‐duration spikelets in the MGF, which we suggest are the product of intermediate giant fiber activation coupled to MGF collateral dendrites. Since these contact sites have immunoreactivity with a glutamate receptor antibody, and the glutamate receptor antagonist 6‐cyano‐7‐nitroquinoxaline‐2,3‐dion abolishes evoked MGF responses, we conclude that the afferent pathway for MGF‐mediated escape is glutamatergic. This electrically coupled sensory network may facilitate rapid escape activation by enhancing the amplitude of giant axon depolarization.
A Fluorescent False Neurotransmitter as a Dual Electrofluorescent Probe for Secretory Cell Models
Authors: Pandard Justine , Pan Na , Ebene Dina H. , Le Saux Thomas , Ait‐Yahiatène Eric , Liu Xiaoqing , Grimaud Laurence , Buriez Olivier , Labbé Eric , Lemaître Frédéric , Guille‐Collignon Manon 
Published: September 2019

AbstractA dual electrofluorescent probe (FFN42) belonging to the fluorescent false neurotransmitter family was rationally designed for investigating cell secretion. This probe, which comprises a coumarin core with one amino and two hydroxy groups, is very promising due to its electroactive and fluorescent properties. The optimal excitation and emission wavelengths (380 nm and 470 nm respectively) make this probe adapted for use in fluorescence microscopy. FFN42 has a quantum yield of 0.18, a molar absorption coefficient of 12000 M−1cm−1 and pKa values of 5.4 and 6.7 for the hydroxy groups. The electroactivity of FFN42 was evidenced on carbon fiber and ITO electrodes at relatively low oxidation potentials (0.24 V and 0.45 V vs Ag/AgCl respectively). Epifluorescence observations showed that FFN42 accumulated into secretory vesicles of PC12 and N13 cells. Toxicity tests further revealed that FFN42 had no lethal effect on these cells. Amperometric data obtained on carbon fiber electrodes proved that the probe is released by N13 cells.
The underestimated problem of oral Candida colonization—An observational pilot study in one nursing home
Authors: Kottmann Hannah Elisa , Derman Sonja Henny Maria , Noack Michael Johannes , Barbe Anna Greta 
Published: September 2019

AbstractObjectivesOlder people are at increased risk of intraoral yeast colonization. In this observational case series, we assessed Candida colonization among nine nursing home residents to investigate possible correlations with their individual characteristics, general health parameters, and oral care. We also described the effect of professional dental cleaning (PDC) including prosthesis cleaning on colonization cases.Materials and methodsGeneral clinical and oral health was assessed in nine residents, and samples were taken from six oral mucosa sites or prosthetic surfaces. PDC was performed to achieve macroscopically clean results, and residents were re‐examined 2 weeks later.ResultsWe found that six residents were intraorally colonized with Candida albicans; four also had Candida glabrata. Prostheses were particularly infected. Dementia, multimorbidity, and presence of prostheses reduced oral hygiene ability; requiring assistance for oral hygiene care was a risk indicator for Candida colonization. PDC reduced C. albicans (at the expense of increased C. glabrata) but was not optimal for maintaining Candida reduction.ConclusionIn this pilot study, Candida colonization is prevalent among nursing home residents, especially those with cognitive impairment, multimorbidity, or reduced oral hygiene capacity. Potential negative effects on general health necessitate diagnostic and therapeutic guidelines. PDC alone did not maintain the reduction in Candida colonization; additional methods for daily oral care are necessary.
Energy consumption optimization for self‐powered IoT networks with non‐orthogonal multiple access
Authors: Li Xi , Luo Changqing , Ji Hong , Zhuang Yuandong , Zhang Heli , Leung Victor C.M. 
Published: September 2019

SummaryEnergy harvesting (EH) has been considered as one of the promising technologies to power Internet of Things (IoT) devices in self‐powered IoT networks. By adopting a typical harvest‐then‐transmit mode, IoT devices with the EH technology first harvest energy by using wireless power transfer (WPT) and then carry out wireless information transmission (WIT), which leads to the coordination between WPT and WIT. In this paper, we consider optimizing energy consumption of periodical data collection in a self‐powered IoT network with non‐orthogonal multiple access (NOMA). Particularly, we take into account time allocation for the WPT and WIT stages, node deployment, and constraints for data transmission. Moreover, to thoroughly explore the impact of different multiple access methods, we theoretically analyse and compare the performance achieved by employing NOMA, frequency division multiple access (FDMA), and time division multiple access (TDMA) in the considered IoT network. To validate the performance of the proposed method, we conduct extensive simulations and show that the NOMA outperforms the FDMA and TDMA in terms of energy consumption and transmission power.
Bat algorithm–based beamforming for mmWave massive MIMO systems
Authors: Shahjehan Waleed , Riaz Asad , Khan Imran , Sadiq Ali Safaa , Khan Suleman , Khan Muhammad Khurram 
Published: September 2019

SummaryIn this paper, an optimized analog beamforming scheme for millimeter‐wave (mmWave) massive MIMO system is presented. This scheme aims to achieve the near‐optimal performance.by searching for the optimized combination of analog precoder and combiner. In order to compensate for the occurrence of attenuation in the magnitude of mmWave signals, the codebook‐dependent analog beamforming in conjunction with precoding at transmitting end and combining signals at the receiving end is utilized. Nonetheless, the existing and traditional beamforming schemes involve a more difficult and complicated search for the optimal combination of analog precoder/combiner matrices from predefined codebooks. To solve this problem, we have referred to a modified bat algorithm to find the optimal combination value. This algorithm will explore the possible pairs of analog precoder/combiner as a way to come up with the best match in order to attain near‐optimal performance. The analysis shows that the optimized beamforming scheme presented in this paper can improve the performance that is very close to the beam steering benchmark that we have considered.
Changes in seasonal precipitation distribution but not annual amount affect litter decomposition in a secondary tropical forest
Authors: Yu Shiqin , Mo Qifeng , Li Yingwen , Li Yongxing , Zou Bi , Xia Hanping , Li Zhi'an , Wang Faming 
Published: September 2019

AbstractIn the tropics of South China, climate change induced more rainfall events in the wet season in the last decades. Moreover, there will be more frequently spring drought in the future. However, knowledge on how litter decomposition rate would respond to these seasonal precipitation changes is still limited. In the present study, we conducted a precipitation manipulation experiment in a tropical forest. First, we applied a 60% rainfall exclusion in April and May to defer the onset of wet season and added the same amount of water in October and November to mimic a deferred wet season (DW); second, we increased as much as 25% mean annual precipitation into plots in July and August to simulate a wetter wet season (WW). Five single‐species litters, with their carbon to nitrogen ratio ranged from 27 to 49, and a mixed litter were used to explore how the precipitation change treatments would affect litter decomposition rate. The interaction between precipitation changes and litter species was not significant. The DW treatment marginally accelerated litter decomposition across six litter types. Detailed analysis showed that DW increased litter decomposition rate in the periods of January to March and October to December, when soil moisture was increased by the water addition in the dry season. In contrast, WW did not significantly affect litter decomposition rate, which was consistent with the unchanged soil moisture pattern. In conclusion, the study indicated that regardless of litter types or litter quality, the projected deferred wet season would increase litter decomposition rate, whereas the wetter wet season would not affect litter decomposition rate in the tropical forests. This study improves our knowledge of how tropical forest carbon cycling in response to precipitation change.
Glucose triggers strong taxon‐specific responses in microbial growth and activity: insights from DNA and RNA qSIP
Authors: Papp Katerina , Hungate Bruce A. , Schwartz Egbert 
Published: September 2019

AbstractGrowth of soil microorganisms is often described as carbon limited, and adding labile carbon to soil often results in a transient and large increase in respiration. In contrast, soil microbial biomass changes little, suggesting that growth and respiration are decoupled in response to a carbon pulse. Alternatively, measuring bulk responses of the entire community (total respiration and biomass) could mask ecologically important variation among taxa in response to the added carbon. Here, we assessed taxon‐specific variation in cellular growth (measured as DNA synthesis) and metabolic activity (measured as rRNA synthesis) following glucose addition to soil using quantitative stable isotope probing with H218O. We found that glucose addition altered rates of DNA and rRNA synthesis, but the effects were strongly taxon specific: glucose stimulated growth and rRNA transcription for some taxa, and suppressed these for others. These contrasting taxon‐specific responses could explain the small and transient changes in total soil microbial biomass. Responses to glucose were not well predicted by a priori assignments of taxa into copiotrophic or oligotrophic categories. Across all taxa, rates of DNA and rRNA synthesis changed in parallel, indicating that growth and activity were coupled, and the degree of coupling was unaffected by glucose addition. This pattern argues against the idea that labile carbon addition causes a large reduction in metabolic growth efficiency; rather, the large pulse of respiration observed with labile substrate addition is more likely to be the result of rapid turnover of microbial biomass, possibly due to trophic interactions. Our results support a strong connection between rRNA synthesis and bacterial growth, and indicate that taxon‐specific responses among soil bacteria can buffer responses at the scale of the whole community.
Associative and Proton Transfer Effects on the Voltammetric Behaviour of Chemically Grafted Films Bearing Nitrophenyl Groups
Authors: Ramírez‐Delgado Vanessa , Morales‐Martínez Daniel , González Felipe J. 
Published: September 2019

AbstractThe spontaneous decomposition of 4‐nitrophenyldiazonium tetrafluoroborate in acetonitrile solution was used to modify glassy carbon electrodes with films bearing nitrophenyl groups. The modification procedure was performed by dipping non‐connected electrodes into the nitrophenyldiazonium solution. When these modified electrodes were analyzed by cyclic voltammetry in acetonitrile containing traces of water over a wide potential scale, only one reduction wave and two oxidation peaks were observed, which is atypical considering the reversible behaviour of the reduction of nitrobenzene in acetonitrile, however in acetonitrile containing a lower concentration of water, two consecutive reduction waves appear in the same potential scale. The difference between both behaviours is consistent with the presence of water trapped into the film structure, which promotes electron and proton transfer reactions that yield nitrosobenzene as product in surface. The trapping of water inside the film structure is justified by the capability of the nitrophenyl groups to interact with water by surface hydrogen bonding interactions.
CE‐MS with electrokinetic supercharging and application to determination of neurotransmitters
Authors: Wells Shane S. , Dawod Mohamed , Kennedy Robert T. 
Published: September 2019

AbstractElectrokinetic supercharging (EKS) is known as one of the most effective online electrophoretic preconcentration techniques, though pairing with it with mass spectrometry has presented challenges. Here, EKS is successfully paired with ESI‐MS/MS to provide a sensitive and robust method for analysis of biogenic amines in biological samples. Injection parameters including electric field strength and the buffer compositions used for the separation and focusing were investigated to achieve suitable resolution, high sensitivity, and compatibility with ESI‐MS. Using EKS, the sensitivity of the method was improved 5000‐fold compared to a conventional hydrodynamic injection with CZE. The separation allowed for baseline resolution of several neurotransmitters within 16 min with LODs down to 10 pM. This method was applied to targeted analysis of seven biogenic amines from rat brain stem and whole Drosophila tissue. This is the first method to use EKS with CE‐ESI‐MS/MS to analyze biological samples.
Full–Life Cycle Toxicity Assessment of Sediment-Bound DDT and Its Degradation Products on Chironomus dilutus
Authors: Ma Ping , Li Huizhen , You Jing 
Published: September 2019

Abstract
Because of its hydrophobicity and persistence, dichlorodiphenyltrichloroethane (DDT) is ubiquitous in sediments and poses significant risk to benthic organisms. Therefore, it is imperative to evaluate the long-term toxicity of DDT. However, limited information is available on its chronic toxicity to benthic invertebrates. Full–life cycle toxicity of sediment-bound DDT to Chironomus dilutus was assessed. Median lethal concentrations (with 95% confidence limits) of DDT and its degradation products (DDX) to C. dilutus were 334 (165–568), 21.4 (11.2–34.3), and 7.50 (4.61–10.6) nmol/g organic carbon after 10-, 20-, and 63-d exposure, respectively. In addition, median effect concentrations of DDX were 20.0 (15.0–25.3), 7.13 (4.10–10.5), and 8.92 (3.32–15.1) nmol/g organic carbon for growth, emergence, and reproduction, respectively. A toxicity spectrum was established to visually summarize chronic effects of DDX to midges. In addition, DDT degraded to dichlorodiphenyldichloroethane (DDD) and dichlorodiphenyldichloroethylene (DDE) during sediment aging, and their toxicity differed from that of the parent compound. Predicted toxic units of DDX in porewater were utilized to distinguish between toxicity from DDT and that of DDD and DDE. The results showed that DDD was the main contributor to the toxicity in C. dilutus. To improve the accuracy of sediment risk assessment of DDT, the composition of DDX should be considered. Environ Toxicol Chem 2019;38:2698–2707. © 2019 SETAC
Abstract
Full–life cycle toxicity testing of sediment-bound DDT to Chironomus dilutus. Chronic toxicity spectrum was established for endpoints of lethality, growth, emergence, and reproduction. DDD = dichlorodiphenyldichloroethane; DDE = dichlorodiphenyldichloroethylene; DDT = dichlorodiphenyltrichloroethane; E = emergence; EC5 and EC50 = 5% and 50% effective concentrations, respectively; G = growth; LC5 and LC50 = 5 and 50% lethal concentrations, respectively; R = reproduction.
Time‐series momentum in China's commodity futures market
Authors: Ham Hyuna , Cho Hoon , Kim Hyeongjun , Ryu Doojin 
Published: September 2019

AbstractThis study examines the time‐series momentum in China's commodity futures market. We find that a time‐series momentum strategy outperforms classical passive long and cross‐sectional momentum strategies in terms of the Sharpe ratio, risk‐adjusted excess returns, and cumulative returns. The time‐series momentum strategy with a 1‐month look‐back period and a 1‐month holding period exhibits the best performance. We observe clear time‐series momentum patterns and find that the time‐series momentum strategy is effective in the Chinese commodity futures market. However, the momentum lasts for less time in China than in the United States because China's futures market seems to have a greater number of speculative investors.