Publications by authors named "Xinxin Guo"

99 Publications

Dementia remains the major predictor of death among octogenarians. A study of two population cohorts of 85-year-olds examined 22 years apart.

Eur J Epidemiol 2021 Apr 21. Epub 2021 Apr 21.

Neuropsychiatric Epidemiology Unit, Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, Centre for Ageing and Health (AGECAP), Sahlgrenska Academy, University of Gothenburg, Wallinsgatan 6, 431 41, Mölndal, SE, Sweden.

Dementia is the major predictor of death in old age. The aim of this paper was to determine whether 8-year mortality among 85-year olds with and without dementia, and if the contribution of dementia to mortality relative to other common diseases has changed. We used two population-based cohorts of 85-year-olds (N = 1065), born in 1901-02 and 1923-24, which were examined with identical methods in 1986-87 and 2008-2010 and followed for 8-year mortality according to data from the Swedish Tax Agency. Dementia was diagnosed according to DSM-III-R. Other diseases were diagnosed based on self-reports, close informant interviews, somatic examinations, and the Swedish National In-patient Register. Compared to cohort 1901-02, cohort 1923-24 had a lower 8-year mortality both among those with (HR 0.7; 95% CI 0.5-0.99) and without dementia (HR 0.7; 95% CI 0.5-0.9). Dementia was associated with increased mortality in both cohorts (cohort 1901-02, HR 2.6; 95% CI 2.0-3.2, cohort 1923-24, HR 2.8; 95% CI 2.3-3.5), and remained the major predictor of death, with a population attributable risk of 31.7% in 1986-87 and 27.7% in 2008-10. Dementia remained the most important predictor of death in both cohorts. The relative risk for mortality with dementia did not change between cohorts, despite a decreased mortality rate in the population.
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http://dx.doi.org/10.1007/s10654-021-00745-5DOI Listing
April 2021

Evidence of Potts-Nematic Superfluidity in a Hexagonal sp^{2} Optical Lattice.

Phys Rev Lett 2021 Jan;126(3):035301

State Key Laboratory of Surface Physics, Institute of Nanoelectronics and Quantum Computing, Department of Physics, Fudan University, Shanghai 200438, China.

As in between liquid and crystal phases lies a nematic liquid crystal, which breaks rotation with preservation of translation symmetry, there is a nematic superfluid phase bridging a superfluid and a supersolid. The nematic order also emerges in interacting electrons and has been found to largely intertwine with multiorbital correlation in high-temperature superconductivity, where Ising nematicity arises from a four-fold rotation symmetry C_{4} broken down to C_{2}. Here, we report an observation of a three-state (Z_{3}) quantum nematic order, dubbed "Potts-nematicity", in a system of cold atoms loaded in an excited band of a hexagonal optical lattice described by an sp^{2}-orbital hybridized model. This Potts-nematic quantum state spontaneously breaks a three-fold rotation symmetry of the lattice, qualitatively distinct from the Ising nematicity. Our field theory analysis shows that the Potts-nematic order is stabilized by intricate renormalization effects enabled by strong interorbital mixing present in the hexagonal lattice. This discovery paves a way to investigate quantum vestigial orders in multiorbital atomic superfluids.
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http://dx.doi.org/10.1103/PhysRevLett.126.035301DOI Listing
January 2021

Wheat FRIZZY PANICLE activates VERNALIZATION1-A and HOMEOBOX4-A to regulate spike development in wheat.

Plant Biotechnol J 2020 Dec 26. Epub 2020 Dec 26.

State Key Laboratory of Plant Cell and Chromosome Engineering, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang, China.

Kernel number per spike determined by the spike or inflorescence development is one important agricultural trait for wheat yield that is critical for global food security. While a few important genes for wheat spike development were identified, the genetic regulatory mechanism underlying supernumerary spikelets (SSs) is still unclear. Here, we cloned the wheat FRIZZY PANICLE (WFZP) gene from one local wheat cultivar. WFZP is specifically expressed at the sites where the spikelet meristem and floral meristem are initiated, which differs from the expression patterns of its homologs FZP/BD1 in rice and maize, indicative of its functional divergence during species differentiation. Moreover, WFZP directly activates VERNALIZATION1 (VRN1) and wheat HOMEOBOX4 (TaHOX4) to regulate the initiation and development of spikelet. The haplotypes analysis showed that the favourable alleles of WFZP associated with spikelet number per spike (SNS) were preferentially selected during breeding. Our findings provide insights into the molecular and genetic mechanisms underlying wheat spike development and characterize the WFZP as elite resource for wheat molecular breeding with enhanced crop yield.
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http://dx.doi.org/10.1111/pbi.13535DOI Listing
December 2020

Increased Precipitation Shapes Relationship between Biochemical and Functional Traits of in Grass-Dominated Rather than Shrub-Dominated Community in a Desert Steppe.

Plants (Basel) 2020 Oct 29;9(11). Epub 2020 Oct 29.

Department of Health and Environmental Science, Xi'an Jiaotong-Liverpool University, Suzhou 215000, China.

Understanding the effects of precipitation variations on plant biochemical and functional traits is crucial to predict plant adaptation to future climate changes. The dominant species, , plays an important role in maintaining the structure and function of plant communities in the desert steppe, Inner Mongolia. However, little is known about how altered precipitation affects biochemical and functional traits of in different communities in the desert steppe. Here, we examined the responses of biochemical and functional traits of in shrub- and grass-dominated communities to experimentally increased precipitation (control, +20%, +40%, and +60%). We found that +40% and +60% increased plant height and leaf dry matter content (LDMC) and decreased specific leaf area (SLA) of in grass community. For biochemical traits in grass community, +60% decreased the contents of protein and chlorophyll b (Cb), while +40% increased the relative electrical conductivity and superoxide dismutase. Additionally, +20% increased LDMC and malondialaenyde, and decreased SLA and protein in shrub community. Chlorophyll a, Cb, carotenoids, protein and superoxide dismutase in the grass community differed with shrub community, while +60% caused differences in SLA, LDMC, leaf carbon content, malondialaenyde and peroxidase between two communities. The positive or negative linear patterns were observed between different functional and biochemical traits in grass- rather than shrub-community. Soil water content explained changes in some biochemical traits in the grass community, but not for functional traits. These results suggest that increased precipitation can affect functional traits of in the grass community by altering biochemical traits caused by soil water content. The biochemical and functional traits of were more sensitive to extreme precipitation in grass- than shrub-community in the desert steppe. Our study highlights the important differences in adaptive strategies of in different plant communities at the same site to precipitation changes.
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http://dx.doi.org/10.3390/plants9111463DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7692965PMC
October 2020

Impact of Electroacupuncture Stimulation on Postoperative Constipation for Patients Undergoing Brain Tumor Surgery.

J Neurosci Nurs 2020 Oct;52(5):257-262

Background: Constipation is frequently encountered in patients undergoing brain tumor resection. Constipation has negative effects on daily living, well-being, and individuals' quality of life. We examined the impact of acupuncture and electroacupuncture (EA) stimulation on postoperative constipation for patients undergoing brain tumor resection.

Methods: Patients undergoing brain tumor resection (n = 150) were randomly divided into a nontreatment group, an acupuncture group, and an EA group. Rome III Diagnostic Criteria, Cleveland Clinic Constipation Score, symptom assessment, Patient Assessment of Constipation Quality of Life questionnaire, Self-Rating Anxiety Scale, and a Self-Rating Depression Scale were collected.

Results: Acupuncture and EA were effective in relieving postoperative constipation. Electroacupuncture decreased constipation and improved quality of life scores.

Conclusion: Acupuncture and EA are novel adjuvant therapies to treat constipation.
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http://dx.doi.org/10.1097/JNN.0000000000000531DOI Listing
October 2020

Brucea javanica oil emulsion injection (BJOEI) as an adjunctive therapy for patients with advanced colorectal carcinoma: A protocol for a systematic review and meta-analysis.

Medicine (Baltimore) 2020 Jul;99(27):e21155

Department of Gastroenterology.

Background: Brucea javanica oil emulsion injection (BJOEI) has been widely applied as a promising adjunctive drug for colorectal carcinoma (CRC). However, the exact effects and safety of BJOEI remains controversial. In this study, we aimed to summarize the efficacy and safety of BJOEI for the treatment of advanced CRC through the meta-analysis, in order to provide scientific reference for the design of future clinical trials.

Methods: Eligible prospective controlled clinical trials were searched from PubMed, Cochrane Library, Google Scholar, Medline, Web of Science (WOS), Excerpt Medica Database (Embase), Chinese BioMedical Database (CBM), China Scientific Journal Database (VIP), China National Knowledge Infrastructure (CNKI) and Wanfang Database. Papers in English or Chinese published from January 2000 to May 2020 will be included without any restrictions. The clinical outcomes including therapeutic effects, quality of life (QoL), immune function and adverse events, were systematically evaluated.Study selection and data extraction will be performed independently by 2 reviewers. Review Manager 5.3 and Stata 14.0 were used for data analysis, and a fixed or random-effect model will be used depending upon the heterogeneity observed between trials. Subgroup and meta-regression analysis will be carried out depending on the availability of sufficient data.

Results: The results of this systematic review will be published in a peer-reviewed journal.

Conclusion: Our study will draw an objective conclusion of the effects and safety of BJOEI for advanced CRC, and provide a helpful evidence for clinicians to formulate the best postoperative adjuvant treatment strategy for CRC patients.INPLASY registration number: INPLASY202060014.
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http://dx.doi.org/10.1097/MD.0000000000021155DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7337478PMC
July 2020

Regulation of Cu and Zn migration in soil by biochar during snowmelt.

Environ Res 2020 07 22;186:109566. Epub 2020 Apr 22.

School of Public Administration and Law, Northeast Agricultural University, Harbin, 150030, China.

To study the migration characteristics of the heavy metals Cu and Zn carried by snowmelt water infiltrating soil during snowmelt periods and the regulation of this process by biochar, field experiments were carried out in which the variation in the Cu and Zn contents in soils on bare land (S1) and in soils with biochar coverage (S2) were analysed before snowfall and during snowmelt periods, and the degree of Cu and Zn pollution was determined on the basis of the enrichment factor (EF) and index of geoaccumulation (I). The migration characteristics of Cu and Zn in soil were studied by combining the migration coefficient and leaching ratio. During the snowmelt period, the use of biochar reduced the migration coefficients of Cu and Zn carried by snowmelt water in shallow soil. The transport coefficients (T) of Cu and Zn in shallow soil (0-30 cm) in the S2 treatment were 0.89 and 0.81, respectively, lower than those in the S1 treatment. In addition, during the snowmelt period, the leaching ratios (C) of Cu and Zn in the 0-10 cm soil layer of the S2 treatment were 0.22 and 0.24 less than those of the S1 treatment, the index of geoaccumulation (I) was 0.52 and 0.23 less, and the enrichment factor (EF) was 1.20 and 0.09 less, respectively. This study provides practical and theoretical guidance for future research on soil heavy metal pollution mitigation.
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http://dx.doi.org/10.1016/j.envres.2020.109566DOI Listing
July 2020

The effect of tillage systems on phosphorus distribution and forms in rhizosphere and non-rhizosphere soil under maize (Zea mays L.) in Northeast China.

Sci Rep 2020 04 20;10(1):6574. Epub 2020 Apr 20.

College of Resources and Environment, Jilin Agricultural University, Changchun, 130118, P.R. China.

An appropriate tillage method must be implemented by maize growers to improve phosphorus dynamics in the soil in order to increase phosphorus uptake by plant. The objective of this study was to investigate the effects of tillage systems on phosphorus and its fractions in rhizosphere and non-rhizosphere soils under maize. An experimental field was established, with phosphate fertilizers applied to four treatment plots: continuous rotary tillage (CR), continuous no-tillage (CN), plowing-rotary tillage (PR), and plowing-no tillage (PN). Under the different tillage methods, the available P was increased in the non-rhizosphere region. However, the concentration of available P was reduced in the rhizosphere soil region. The soil available P decreased with the age of the crop until the maize reached physiological maturity. The non-rhizosphere region had 132.9%, 82.5%, 259.8%, and 148.4% more available P than the rhizosphere region under the CR, PR, CN, and PN treatments, respectively. The continuous no-tillage method (CN) improved the uptake of soil phosphate by maize. The concentrations of Ca-P, Ca-P, Fe-P, Al-P and O-P at the maturity stage were significantly lower than other seedling stages. However, there was no significant relationship between total P and the P fractions. Therefore, a continuous no-tillage method (CN) can be used by farmers to improve phosphorus availability for spring maize. Soil management practices minimizing soil disturbance can be used to impove phosphorus availability for maize roots, increase alkaline phosphatase activity in the rhizosphere soil and increase the abundance of different phosphorus fractions.
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http://dx.doi.org/10.1038/s41598-020-63567-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7171091PMC
April 2020

Hydrogen production driven by formate oxidation in Shewanella oneidensis MR-1.

Appl Microbiol Biotechnol 2020 Jun 17;104(12):5579-5591. Epub 2020 Apr 17.

School of Resource and Environmental Engineering, Anhui University, Hefei, 230601, China.

Shewanella oneidensis MR-1 is a potent hydrogen producer in the deficiency of exogenous electron acceptors. The electron transfer pathway for hydrogen production remains unclear, although enzymes for hydrogen production have been identified in S. oneidensis MR-1. In this study, we investigated the electron transfer pathway from formate to hydrogen, given that formate is commonly a key chemical for bacterial hydrogen production. We revealed that two formate dehydrogenases FdhA1B1C1 and FdhA2B2C2, rather than FdnGHI, played a dominant role in formate-driven hydrogen production. Menaquinone was indispensable for the electron transfer from formate to hydrogen, which excluded the presence of formate hydrogen-lyase in S. oneidensis MR-1. A previously proposed formate dehydrogenase subunit HydC was identified as a menaquinone-binding subunit of [FeFe] hydrogenase HydAB, and the hydABC operon is conserved in bacteria living in diverse environments. A formate exporter FocA and transcriptional regulator FhlA were identified for their effect on formate metabolism and hydrogen production. FhlA positively affected the metabolism of formate and hydrogen by regulating the expression of fdhA2B2C2, fdnGHI, focA, and dld-II. Overall, the electron transfer pathway deciphered in this work will facilitate the improvement of biohydrogen production by S. oneidensis MR-1.Key Points• The electron transfer pathway from formate to hydrogen in MR-1 is deciphered.• Menaquinone is indispensable for hydrogen production.• A cytochrome b subunit transfers electrons from menaquinone to [FeFe] hydrogenase.
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http://dx.doi.org/10.1007/s00253-020-10608-wDOI Listing
June 2020

Analysis of Heavy Metal Contamination of Agricultural Soils and Related Effect on Population Health-A Case Study for East River Basin in China.

Int J Environ Res Public Health 2020 03 18;17(6). Epub 2020 Mar 18.

Department of Public Health Sciences, University of Hawaii at Mānoa, 1960 East-West Road, Honolulu, HI 96822, USA.

To understand the heavy metal pollution in agricultural soils along the East River basin and assess the pollution related health effect to local residents, interviews and archived data were obtained to identify the study sites affected by polluted tailing. Soil samples were collected and tested for heavy metal content and the Comprehensive Pollution Index (CPI). The degree of pollution of agricultural soils in the area was assessed using GIS-based Spatial distribution map of heavy metals and the trend of soil heavy metal risk. Two villages (Matian and Zhudui) near the East River were included in this study for health effect assessment. A total of 193 residents aged 15 or above from each village were tested for the present status of chronic diseases. Convenient sampling method was used to collect blood samples from 78 residents for heavy metal concentration. The contents of Pb, Cd, As, Zn, and Cu in the agricultural soils were all over the standards with a moderate to severe CPI. Among these metals, Cd was the highest followed by Pb, and Cu was the lowest. The contents of Pb, Cd, As, and Zn tend to be higher in soils closer to the river. The prevalence of chronic diseases was over 30%, which is significantly higher than the report from the national central region (23.15%). The average blood lead level (BLL) among children under 14 years is 7.42 μg/dL. Although the adults in Matian village had a significantly higher BLL (χ = 8.70, = 0.03) as compared to Zhudui village, there was no significant difference for the prevalence of chronic diseases between the two villages (χ = 3.23, = 0.09). The mean BLL of children and the proportion of children with BLL ≥ 10 µg/dL in this study are equivalent to the national average. The higher BLL concentration and prevalence of chronic diseases in adults might be due to their long-term exposure to heavy metal contamination environment and higher background level of heavy metals. Findings from this study will form the baseline information for local government to the development of effective approaches to control the heavy metal contamination and reduce the pollution related adverse health effect on local residents.
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http://dx.doi.org/10.3390/ijerph17061996DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7143142PMC
March 2020

The serum concentration of βCGRP is novel marker for type 1 diabetes.

Heliyon 2020 Jan 16;6(1):e03223. Epub 2020 Jan 16.

Department of Reproductive Medicine Centre, 1st Affiliated Hospital; Fujian Medical University, Fuzhou, China.

Objective: Dysregulation of neuropeptides, such as calcitonin gene-related peptide (CGRP) is thought to play significant roles in diabetes. In the present study, we investigated the importance of beta-calcitonin gene related peptide (βCGRP, ) in the development of type 1 diabetes (T1D).

Methods: There were fifty-eight patients with T1D and 320 age and gender-matched healthy controls in Chinese Han population were included, the genotypes of were analyzed by direct sequencing and the clinicopathologic parameters of patients were also evaluated.

Results: Among the SNPs genotyped, the C allele of _rs3829220 T (c.224G + 846) and rs382922 C (c.224G + 848) were positively associated with T1D (OR = 2.67 and 3.42, respectively). Serum βCGRP of patients is 1.58 times higher compare to normal control. Immunohistochemistry analysis revealed βCGRP expression in the infiltrating lymphocytes of pancreas from T1D mice as compared to normal control.

Conclusion: Our findings indicate that the presence of βCGRP is a probable molecular basis for the initial events triggered in T1D.
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http://dx.doi.org/10.1016/j.heliyon.2020.e03223DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6970168PMC
January 2020

Reinforcement Learning-Based Nearly Optimal Control for Constrained-Input Partially Unknown Systems Using Differentiator.

IEEE Trans Neural Netw Learn Syst 2020 Nov 29;31(11):4713-4725. Epub 2020 Oct 29.

In this article, a synchronous reinforcement-learning-based algorithm is developed for input-constrained partially unknown systems. The proposed control also alleviates the need for an initial stabilizing control. A first-order robust exact differentiator is employed to approximate unknown drift dynamics. Critic, actor, and disturbance neural networks (NNs) are established to approximate the value function, the control policy, and the disturbance policy, respectively. The Hamilton-Jacobi-Isaacs equation is solved by applying the value function approximation technique. The stability of the closed-loop system can be ensured. The state and weight errors of the three NNs are all uniformly ultimately bounded. Finally, the simulation results are provided to verify the effectiveness of the proposed method.
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http://dx.doi.org/10.1109/TNNLS.2019.2957287DOI Listing
November 2020

Asymmetric population of momentum distribution by quasi-periodically driving a triangular optical lattice.

Opt Express 2019 Sep;27(20):27786-27796

Ultracold atoms in periodical-driven optical lattices enable us to investigate novel band structures and explore the topology of the bands. In this work, we investigate the impact of the ramping process of the driving signal and propose a simple but effective method to realize desired asymmetric population in momentum distribution by controlling the initial phase of the driving signal. A quasi-momentum oscillation along the shaking direction in the frame of reference co-moving with the lattice is formed, causing the formation of the mix of ground energy band and first excited band in laboratory frame, within the regime that the driving frequency is far less than the coupling frequency between ground band and higher energy bands. This method avoids the construction of intricate lattices or complex control sequence. With a triangular lattice, we experimentally investigate the influence of the initial phase, frequency, amplitude of the driving signal on the population difference and observe good agreement with our theoretical model. This provides guidance on how to load a driving signal in driven optical lattice experiment and also potentially supplies a useful tool to form a qubit that can be used in quantum computation.
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http://dx.doi.org/10.1364/OE.27.027786DOI Listing
September 2019

Testing Mechanical Properties of Rock Bolt under Different Supports Using Fiber Bragg Grating Technology.

Sensors (Basel) 2019 Sep 22;19(19). Epub 2019 Sep 22.

Key Laboratory of Transportation Tunnel Engineering, Ministry of Education, Southwest Jiaotong University, Chengdu 610031, China.

Fiber Bragg grating (FBG) sensors, which can accurately measure strain, can be integrated with rock bolts with small fingerprints. In this paper, according to the force mechanism of prestressed anchor and non-prestressed anchor, different loading modes were designed, named active loading mode and passive loading mode. Then, FBG technology was used to monitor the axial force variation of prestressed anchor and non-prestressed anchor in different loading modes. Based on the test results, it is found that when the anchoring force is relatively small (<35 kN), prestressed anchors need to be tested by active loading mode, and non-prestressed anchors need to be tested by passive loading mode. For the prestressed anchor, the force condition of the bolt-shaft was similar to that of the two-force bar, and the axial force of the bolt-shaft was nearly the same along its entire length. Taking the applied load as the reference, the change rate of the axial force of the bolt-shaft was less than 10%. For non-prestressed anchor, due to the plate, there is a certain area surrounding the plate where the axial force of the bolt-shaft was greatly influenced. With applied loads of less than 15 kN, the change rate of the axial force on FBG1 was greater than 10%. With applied loads of greater than 20 kN, this was less than 10%. In this area, influenced by the plate, the axial force of the bolt-shaft increases, and as the applied load of the pullout test increases, the influence decreases.
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http://dx.doi.org/10.3390/s19194098DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6806244PMC
September 2019

The reaction pathway analysis of phosphoric acid with the active radicals: a new insight of the fire-extinguishing mechanism of ABC dry powder.

J Mol Model 2019 Jul 31;25(8):255. Epub 2019 Jul 31.

College of Safety and Engineering, Nanjing Tech University, Nanjing, 210009, China.

Dry powder fire-extinguishing agent is one of Halon substitutes due to its superior fire-extinguishing performance, non-toxicity, and environmental friendliness. As one of the most widely used dry powders, ABC dry powder has attracted wide attention. Understanding its reaction mechanism is important to the design of more efficient compound dry powder based on it. When ABC dry powder was applied to the flame, ammonium dihydrogen phosphate (the main fire-extinguishing component of ABC dry powder) would rapidly decompose into phosphoric acid (HPO) and ammonia. Therefore, in order to figure out the chemical reaction mechanism of ABC dry powder and active radicals, the main focus of this paper is on the HPO. Analysis of the electrostatic potential on van der Waals surface of HPO was carried out. Besides, detailed theoretical investigation has been performed on the mechanism, kinetics, and thermochemistry of the reactions of HPO with H, OH, and CH radicals and further decomposition of HPO using M06-2X/6-311G(d,p)//CCSD(T)/cc-pVTZ level of theory. Mayer bond order for all intrinsic reaction coordinate points was also calculated. Finally, it is theoretically proved that ABC dry powder extinguishes the fire mainly by chemical inhibition on H and OH radicals. Grapical Abstract .
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http://dx.doi.org/10.1007/s00894-019-4136-yDOI Listing
July 2019

Frequency-doubling effect in acoustic reflection by a nonlinear, architected rotating-square metasurface.

Phys Rev E 2019 May;99(5-1):052209

John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA.

Nonlinear acoustic metamaterials offer the potential to enhance wave control opportunities beyond those already demonstrated via dispersion engineering in linear metamaterials. Managing the nonlinearities of a dynamic elastic system, however, remains a challenge, and the need now exists for new strategies to model and design these wave nonlinearities. Inspired by recent research on soft architected rotating-square structures, we propose herein a design for a nonlinear elastic metasurface with the capability to achieve nonlinear acoustic wave reflection control. The designed metasurface is composed of a single layer of rotating squares connected to thin and highly deformable ligaments placed between a rigid plate and a wall. It is shown that during the process of reflection at normal incidence, most of the incoming fundamental wave energy can be converted into the second harmonic wave. A conversion coefficient of approximately 0.8 towards the second harmonic is derived with a reflection coefficient of <0.05 at the incoming fundamental frequency. The theoretical results obtained using the harmonic balance method for a monochromatic pump source are confirmed by time-domain simulations for wave packets. The reported design of a nonlinear acoustic metasurface can be extended to a large family of architected structures, thus opening new avenues for realistic metasurface designs that provide for nonlinear or amplitude-dependent wave tailoring.
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http://dx.doi.org/10.1103/PhysRevE.99.052209DOI Listing
May 2019

Impaired AMPK‑CGRP signaling in the central nervous system contributes to enhanced neuropathic pain in high‑fat diet‑induced obese rats, with or without nerve injury.

Mol Med Rep 2019 Aug 6;20(2):1279-1287. Epub 2019 Jun 6.

Department of Pain Medicine, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110000, P.R. China.

Obesity is associated with increased sensitivity to pain, including neuropathic pain, but the precise mechanisms are not fully understood. Recent evidence has revealed that AMP‑activated protein kinase (AMPK) in the central nervous system (CNS) regulates the neuropeptide calcitonin gene‑related peptide (CGRP), a principal neurotransmitter of the class C nerve fiber, which serves an important role in initiating and maintaining neuropathic pain. AMPK has been demonstrated to be downregulated in the CNS in obesity. The present study hypothesized that obesity may lead to increased sensitivity to neuropathic pain by downregulating AMPK and upregulating CGRP expression levels in the CNS. Sprague‑Dawley rats consuming a high‑fat diet (HF) for 12 weeks developed obesity; they exhibited significantly decreased levels of phospho (p)‑AMPK and increased CGRP expression levels in the spinal cord (SC) and dorsal root ganglion (DRG), respectively, compared with rats consuming a low‑fat (LF) diet. HF‑fed rats that underwent spared nerve injury (SNI) also exhibited lower p‑AMPK and higher CGRP expression levels in the SC and DRG, compared with the corresponding LF‑diet rats. The 50% paw withdrawal threshold (PWT; as measured by Von Frey testing) was significantly lower in HF‑fed compared with LF‑fed rats, with or without SNI. Through intrathecal treatment, the AMPK activator 5‑aminoimidazole‑4‑carboxamide riboside (AICAR) or the CGRP antagonist CGRP8‑37 decreased CGRP expression levels and increased the 50% PWT; however, the AMPK inhibitor dorsomorphin augmented CGRP expression levels and further reduced the 50% PWT in HF‑fed rats, but not LF‑fed rats, with or without SNI. The results indicated that blocking the AMPK‑CGRP pathway may enhance neuropathic pain in HF‑induced obesity, with or without nerve injury. Targeting AMPK in the CNS may be a novel strategy for the prevention and treatment of obesity‑associated neuropathic pain.
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http://dx.doi.org/10.3892/mmr.2019.10368DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6625401PMC
August 2019

Longstanding psychological stress in relation to biomarkers of neuronal dysfunction in cerebrospinal fluid: a 25-year follow-up study in women.

Neurobiol Aging 2019 08 27;80:111-115. Epub 2019 Feb 27.

Department of Psychiatry and Neurochemistry, Sahlgrenska Academy, Centre for Ageing and Health (AgeCap), University of Gothenburg, Sweden.

Longstanding psychological stress has been associated with increased risk of neurodegenerative disorders, such as dementia and Alzheimer's disease. In a prospective population study of women (n = 81), we tested if midlife stress (mean age 49 years) was associated with late-life biomarkers of neurodegeneration in cerebrospinal fluid (CSF) (mean age 74 years) in linear regression models. It was found that women who report of stress at baseline (n = 20) had higher levels of CSF visinin-like protein-1 (VILIP-1) (age adjusted β = 0.113, p = 0.017) and CSF myelin basic protein (β = 0.060, p = 0.030) compared with women without midlife stress (n = 61). There was also a trend observed for higher CSF neurofilament light (β = 0.133, p = 0.056). In addition, longer periods of stress (i.e., stress at 2-3 midlife examinations) were associated with higher levels of CSF VILIP-1. The results suggest that longstanding stress might be associated with neurodegenerative processes in the brain, as CSF VILIP-1 is an unspecific marker for neuronal injury and CSF myelin basic protein reflects neuroaxonal demyelination.
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http://dx.doi.org/10.1016/j.neurobiolaging.2019.02.013DOI Listing
August 2019

Extraction and identification of noise patterns for ultracold atoms in an optical lattice.

Opt Express 2019 Apr;27(9):12710-12722

To extract useful information about quantum effects in cold atom experiments, one central task is to identify the intrinsic fluctuations from extrinsic system noises of various kinds. As a data processing method, principal component analysis can decompose fluctuations in experimental data into eigenmodes, and give a chance to separate noises originated from different physical sources. In this paper, we demonstrate for Bose-Einstein condensates in one-dimensional optical lattices that the principal component analysis can be applied to time-of-flight images to successfully separate and identify noises from different origins of leading contribution, and can help to reduce or even eliminate noises via corresponding data processing procedures. The attribution of noise modes to their physical origins is also confirmed by numerical analysis within a mean-field theory. As the method does not rely on any a priori knowledge of the system properties, it is potentially applicable to the study of other quantum states and quantum critical regions.
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http://dx.doi.org/10.1364/OE.27.012710DOI Listing
April 2019

Event-Triggered Reinforcement Learning-Based Adaptive Tracking Control for Completely Unknown Continuous-Time Nonlinear Systems.

IEEE Trans Cybern 2020 Jul 29;50(7):3231-3242. Epub 2019 Mar 29.

In this paper, event-triggered reinforcement learning-based adaptive tracking control is developed for the continuous-time nonlinear system with unknown dynamics and external disturbances. The critic and action neural networks are designed to approximate an unknown long-term performance index and controller, respectively. The dead-zone event-triggered condition is developed to reduce communication and computational costs. Rigorous theoretical analysis is provided to show that the closed-loop system can be stabilized. The weight errors and the filtered tracking error are all uniformly ultimately bounded. Finally, to demonstrate the developed controller, the simulation results are provided using an autonomous underwater vehicle model.
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http://dx.doi.org/10.1109/TCYB.2019.2903108DOI Listing
July 2020

Dichloroacetic acid upregulates apoptosis of ovarian cancer cells by regulating mitochondrial function.

Onco Targets Ther 2019 28;12:1729-1739. Epub 2019 Feb 28.

Department of Obstetrics and Gynecology, The First Hospital of Jilin University, Changchun 130021, China,

Background: Metabolic reprogramming is a characteristic of tumor cells and is considered a potential therapeutic target. Even under aerobic conditions, tumor cells use glycolysis to produce energy, a phenomenon called the "Warburg effect". Pyruvate dehydrogenase kinase 1 (PDK1) is a key factor linking glycolysis and the tricarboxylic acid cycle. Dichloroacetic acid (DCA) reverses the Warburg effect by inhibition of PDK1 to switch cytoplasmic glucose metabolism to mitochondrial oxidative phosphorylation (OXPHOS).

Methods: Cell viability was examined using a standard MTT assay. Glucose consumption and l-lactate production were measured using commercial colorimetric kits, and intracellular lactate dehydrogenase (LDH) activity was evaluated using cell lysates and an LDH Quantification Kit. Real-time PCR was used to detect the expression of related genes. The production of total ROS was evaluated by staining with dichlorofluorescin diacetate.

Results: Comparison of various aspects of glucose metabolism, such as expression of key enzymes in glycolysis, lactate production, glucose consumption, mitochondrial oxygen consumption rate, and citric acid production, revealed that A2780/DDP cells were primarily dependent on glycolysis whereas A2780 cells were primarily dependent on mitochondrial OXPHOS. Mitochondrial uncoupling protein 2 (UCP2) protects against mitochondrial ROS while allowing energy metabolism to switch to glycolysis. Treatment of A2780 cells with various concentrations of DCA resulted in decreased expression of UCP2, a metabolic switch from glycolysis to mitochondrial OXPHOS, and an increase in oxidative stress induced by ROS. These effects were not observed in A2780/DDP cells with higher UCP2 expression suggesting that UCP2 might induce changes in mitochondrial functions that result in different sensitivities to DCA.

Conclusion: Our results show that a drug targeting tumor metabolic changes affects almost the entire process of glucose metabolism. Thus, it is necessary to comprehensively determine tumor metabolic functions to facilitate individualized antitumor therapy.
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http://dx.doi.org/10.2147/OTT.S194329DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6419601PMC
February 2019

Noninvasive in vivo glucose detection in human finger interstitial fluid using wavelength-modulated differential photothermal radiometry.

J Biophotonics 2019 07 1;12(7):e201800441. Epub 2019 Apr 1.

Department of Mechanical and Industrial Engineering, Center for Advanced Diffusion-Wave and Photoacoustic Technologies (CADIPT), University of Toronto, Toronto, Ontario, Canada.

We present a noninvasive and noncontacting biosensor using Wavelength Modulated Differential Photothermal Radiometry (WM-DPTR) to monitor blood glucose concentration (BGC) through interstitial fluid (ISF) probing in human middle fingers. WM-DPTR works in the interference-free mid-infrared range with differential wavelengths at the peak and baseline of the fundamental glucose molecule absorption band, giving rise to high glucose sensitivity and specificity. In vivo WM-DPTR measurements and simultaneous finger pricking BGC reference measurements were performed on diabetic and nondiabetic volunteers during oral glucose tolerance testing. The measurement results demonstrated high resolution and large dynamic range (~80 deg) change in phase signal in the normal-to-hyperglycemia BGC range (5 mmol/L to higher than 33.2 mmol/L), which were supported by negative control measurements. The immunity to temperature variation of WM-DPTR yields precise and accurate noninvasive glucose measurements in the ISF.
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http://dx.doi.org/10.1002/jbio.201800441DOI Listing
July 2019

Cognitive and physical activity and dementia: A 44-year longitudinal population study of women.

Neurology 2019 03 20;92(12):e1322-e1330. Epub 2019 Feb 20.

From the Department of Psychiatry and Neurochemistry (J.N., S.O., P.G., V.S., L.J., S.K., X.G., T.H., I.S.), Institute of Neuroscience and Physiology, The Sahlgrenska Academy at Gothenburg University, Mölndal; and the Department of Epidemiology and Social Medicine (V.S.), The Sahlgrenska Academy at Gothenburg University, Gothenburg, Sweden.

Objective: To investigate whether cognitive and physical activities in midlife are associated with reduced risk of dementia and dementia subtypes in women followed for 44 years.

Methods: A population-based sample of 800 women aged 38-54 years (mean age 47 years) was followed from 1968 to 2012. Cognitive (artistic, intellectual, manual, religious, and club) and physical activity were assessed at baseline. During follow-up, dementia (n = 194), Alzheimer disease (n = 102), vascular dementia (n = 27), mixed dementia (n = 41), and dementia with cerebrovascular disease (n = 81) were diagnosed according to established criteria based on information from neuropsychiatric examinations, informant interviews, hospital records, and registry data. Cox regression models were used with adjustment for age, education, socioeconomic status, hypertension, body mass index, cigarette smoking, diabetes mellitus, angina pectoris, stress, and major depression.

Results: We found that cognitive activity in midlife was associated with a reduced risk of total dementia (hazard ratio [HR] 0.66; 95% confidence interval [CI] 0.49-0.89) and Alzheimer disease (HR 0.54; 95% CI 0.36-0.82) during follow-up. Physical activity in midlife was associated with a reduced risk of mixed dementia (HR 0.43; 95% CI 0.22-0.86) and dementia with cerebrovascular disease (HR 0.47; 95% CI 0.28-0.78). The results were similar after excluding those who developed dementia before 1990 (n = 21), except that physical activity was then also associated with reduced risk of total dementia (HR 0.67; 95% CI 0.46-0.99).

Conclusion: Our findings suggests that midlife cognitive and physical activities are independently associated with reduced risk of dementia and dementia subtypes. The results indicate that these midlife activities may have a role in preserving cognitive health in old age.
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http://dx.doi.org/10.1212/WNL.0000000000007021DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6511097PMC
March 2019

Magnetic micro-particle conditioning-pressurized vertical electro-osmotic dewatering (MPEOD) of activated sludge: Role and behavior of moisture and organics.

J Environ Sci (China) 2018 Dec 5;74:147-158. Epub 2018 Mar 5.

Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, State Ministry of Education, Chongqing University, Chongqing 400045, China.

In this study, a magnetic micro-particle conditioning-pressurized vertical electro-osmotic dewatering (MPEOD) process with magnetic micro-particle conditioning-drainage under gravity-mechanical compression-electrical compression (MMPC-DG-MC-EC) stages was established to study the distribution and migration of water, extracellular polymeric substances (EPS), and other organic matter in the activated sludge (AS) matrix at each stage. Results showed that the MPEOD process could attain 53.52% water content (WC) in dewatered AS with bound water (BW) and free water (FW) reduction rates of 82.97% and 99.67%, respectively. The coagulation and time-delayed magnetic field effects of magnetic micro-particles (MMPs) along the MMPC-DG-MC stages initiated the transformation of partial BW to FW in AS. EC had a coupling driving effect of electro-osmosis and pressure on BW, and the changes in pH and temperature at EC stage induced the aggregation of AS flocs and the release of partial BW. Additionally, MMPs dosing further improved the dewatering performance of AS by acting as skeleton builders to provide water passages. Meanwhile, MMPs could disintegrate sludge cells and EPS fractions, thereby reducing tryptophan-like protein and byproduct-like material concentrations in LB-EPS as well as protein/polysaccharide ratio in AS matrix, which could improve AS filterability. At EC stage, the former four Ex/Em regions of fluorescence regional integration analysis for EPS were obviously reduced, especially the protein-like substances in LB- and TB-EPS, which contributed to improvement of AS dewaterability.
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http://dx.doi.org/10.1016/j.jes.2018.02.020DOI Listing
December 2018

Increased Risk of Dementia in Subjective Cognitive Decline if CT Brain Changes are Present.

J Alzheimers Dis 2018 ;66(2):483-495

Neuropsychiatric Epidemiology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Sweden.

Background: Subjective cognitive decline (SCD) has low predictive value for incident dementia.

Objectives: We examined whether CT detectable brain changes add predictive value to SCD in a population sample with high scores on the Mini-Mental State Examination.

Methods: Subjective reports of memory and executive function were gathered in a non-demented population sample ≥70 years (n = 921). CT-brain was performed at baseline (n = 626). Brain atrophy, infarcts, and white matter lesions (WMLs) were classified using visual ratings. Dementia incidence was evaluated periodically during 12 years.

Results: The prevalence of SCD was 32.5% among individuals without dementia. During follow-up, 151 individuals (16.4%) developed dementia. The risk of dementia was increased in SCD, and increased further with WMLs and cortical atrophy present. However, the positive predictive values for incident dementia were low, 25% in SCD and 41% in SCD with WMLs and cortical atrophy.

Conclusion: Our observations add clinical value to the use of SCD and CT to select relevant populations for interventions against dementia, but more stringent screening methods are necessary to reach individuals at risk.
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http://dx.doi.org/10.3233/JAD-180073DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6218129PMC
October 2019

Highly sensitive and specific noninvasive alcohol detection using wavelength-modulated differential photothermal radiometry.

Biomed Opt Express 2018 Oct 5;9(10):4638-4648. Epub 2018 Sep 5.

Alcohol Countermeasure Systems Corp, 60 International Boulevard, Toronto, ON M9W 6J2, Canada.

This paper reports the application of wavelength modulated differential photothermal radiometry (WM-DPTR) to blood alcohol (ethanol) concentration (BAC) measurements in the mid-infrared range to prevent impaired driving. alcohol consumption measurements performed in the BAC range of interest (0-80 mg/dl) with an optimal wavelength pair demonstrated the alcohol detection capability of WM-DPTR with high resolution (~5 mg/dl) and a low detection limit (~10 mg/dl). Oral glucose tolerance tests using both glucose and alcohol sensitive wavelength pairs in the normal-to-hyperglycemia range (~80-320 mg/dl) proved the blood glucose screening ability and ethanol detection specificity of WM-DPTR. The immunity of WM-DPTR to temperature and glucose variation makes the differential signals alcohol sensitive and specific, yielding precise and accurate noninvasive alcohol measurements in the interstitial fluid.
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http://dx.doi.org/10.1364/BOE.9.004638DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6179421PMC
October 2018

Midlife Stress in Relation to Late-Life Cerebrospinal Fluid Biomarkers of Alzheimer's Disease: A 25-Year Follow-Up Study.

Dement Geriatr Cogn Disord 2018 24;46(1-2):90-99. Epub 2018 Aug 24.

Department of Psychiatry and Neurochemistry, Sahlgrenska Academy, Centre for Ageing and Health (AgeCap), University of Gothenburg, Gothenburg, Sweden.

Background/aims: Psychological stress has previously been associated with higher risk of developing late-life dementia, especially Alzheimer's disease (AD). This study tested whether longstanding midlife stress is related to cerebrospinal fluid (CSF) biomarkers of late-life AD, such as tau protein and amyloid beta (Aβ).

Methods: The study included 79 nondemented females from the Prospective Population Study of Women in Gothenburg, Sweden, who responded to a standardized stress question at baseline (mean age 49 years) and underwent a lumbar puncture at follow-up 25 years later. Multiple linear regression models analyzed the relationships between midlife psychological stress and late-life CSF measures of total tau (t-tau), phosphorylated tau (p-tau), Aβ40, and Aβ42.

Results: Longstanding stress in midlife was associated with higher levels of CSF t-tau (β = 0.64, p = 0.01) and Aβ40 (β = 0.60, p = 0.02) in late life. No associations were found between midlife stress and levels of p-tau or Aβ42.

Conclusion: The findings suggest that longstanding stress stimulates unspecific neurodegenerative processes, but not the core processes of AD, at least not in the early phase of the disease. The association with higher concentration of CSF t-tau may reflect neural degeneration and the association with higher Aβ40 may be an early sign of Aβ overproduction or cerebrovascular processes in the brain.
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http://dx.doi.org/10.1159/000490885DOI Listing
November 2018

Integrated analysis of the prognostic role of the lymph node ratio in node-positive gastric cancer: A meta-analysis.

Int J Surg 2018 Sep 10;57:76-83. Epub 2018 Aug 10.

Department of Gastrointestinal Medical Oncology, Harbin Medical University Cancer Hospital, Harbin, 150040, China. Electronic address:

Background: The lymph node ratio (LNR) as a prognostic parameter for gastric cancer has yet to be fully validated in the current tumor node metastasis staging system. We assessed the prognostic role of LNR in lymph node-positive gastric cancer through a meta-analysis.

Materials And Methods: PubMed and EMBASE were searched for relevant studies up until December 2016. The effect measure for meta-analysis of primary outcomes was the hazard ratio (HR) for overall survival. Pooled HRs and 95% confidence intervals were calculated using random effects models. The I statistic was used to measure heterogeneity. Subgroup analysis and meta-regression were chosen to illustrate the potential heterogeneity of the risk factors of outcomes. Publication bias was assessed using Egger's test and Begg's funnel plots. Sensitivity analysis was applied to evaluate the origin of the heterogeneity.

Results: We included 27 studies in this meta-analysis. Higher LNRs were significantly associated with a shorter overall survival (OS). High heterogeneity among the studies was identified (I = 85.6), and the publication bias was moderate. Subgroup analysis showed similar results, and elevated LNR was associated with late-stage gastric cancer and indicative of a worse prognosis. Univariate meta-regression analysis of OS indicated that both treatment type and ethnicity may be causes of heterogeneity in patients with gastric cancer (p values were 0.005 and 0.008, respectively).

Conclusion: LNR was associated with a significantly poorer OS and LNR was an independent predictor of survival in patients with gastric cancer. LNR should be added as one of the parameters to be used in future tumor staging classification systems.
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http://dx.doi.org/10.1016/j.ijsu.2018.08.002DOI Listing
September 2018

Organic carbon content and humus composition after application aluminum sulfate and rice straw to soda saline-alkaline soil.

Environ Sci Pollut Res Int 2019 May 14;26(14):13746-13754. Epub 2018 Jul 14.

College of Resource and Environment, Key Laboratory of Soil Resource Sustainable Utilization for Jilin Province Commodity Grain Bases, Jilin Agricultural University, Changchun, 130118, China.

The soil organic carbon accumulation in soda saline-alkaline soil and the humus composition changes with application of aluminum sulfate and rice straw were investigated by the controlled simulative experiments in laboratory. For evaluating the amelioration effect, organic carbon content and humus composition in soda saline-alkaline soil were investigated with different application amounts of rice straw and aluminum sulfate. Potassium dichromate oxidation titration (exogenous heat) method and Kumada method were used to analyze the contents of organic carbon and humus composition, respectively. The transformation of soil organic matter in the saline-alkali soil during the amelioration has been clarified in this paper. The results demonstrated that the contents of soil organic carbon were significantly increased (13-92%) with different application amounts of rice straw and aluminum sulfate. The contents of free fraction and combined fraction of humus and their compositions (humic acid and fulvic acid) were increased with different application amounts of rice straw. The free fraction of humus was increased more dramatically. Due to aluminum sulfate application, free fraction of humus and humic acid (HA) was transformed to combined fraction partially. Free HA was changed to be P type with rice straw application. With aluminum sulfate application, free form of HA was changed from type P to type Rp. For rice straw application, combined HA only was transferred within the area of type A. Aluminum sulfate addition had no significant effect on the type of combined form of HA. With the same amount of rice straw application, the contents of soil organic carbon were increased by increasing the amount of aluminum sulfate application. Both rice straw and aluminum sulfate applications could reduce the humification degree of free and combined fraction of HA. According to the types of HA, it could be concluded that humus became younger and renewed due to the application of rice straw and aluminum sulfate.
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http://dx.doi.org/10.1007/s11356-018-2270-1DOI Listing
May 2019