bluuebunny/crossref_metadata_2025 huggingface dataset:
Variation Characteristics of the Main Hydrochemical Indexes in Typical Subterranean Rivers in the South China Karst Region Based on Curve Fitting
Authors: Liu Shuyi , Liang Chuan , Wang Lina , Zeng Lingwei , Wang Chunyi
Published: March 2019

The water quality of subterranean rivers in the South China Karst region has undergone dramatic changes resulting from industrial and social development over the past 60 years. The combination of sampling results from subterranean rivers in four typical study areas in the South China Karst region from October to December 2015 (dry season) and correlation analysis using SPSS revealed that the main ions K+, Na+, and SO42- exhibited a significant correlation (p<0.01) and that Ca2+, HCO3-, and Mg2+ exhibited a good correlation (p<0.01). Additionally, we consolidated the data collected since 1960 and, by applying MATLAB, a variety of fitting curve methods were used to fit all the data, and the results showed that cubic spline interpolation fitting performed the best. The squared correlation coefficients (R2) of the obtained fitting curves for Ca2+, HCO3-, and Mg2+ are 0.8545, 0.8689, and 0.7632, respectively, and the corrected R2 values are 0.6739, 0.7088, and 0.4853, respectively. The R2 values of the obtained fitting curves for K+, Na+, Cl-, SO42-, and NO3- are 0.9085, 0.8964, 0.7531, 0.6222, and 0.7997, respectively, and the corrected R2 values are 0.7904, 0.7669, 0.5272, 0.2815, and 0.6127, respectively, indicating excellent fits. Based on the fitting curves, the overall water quality conditions in the karst region were analyzed and compared. Finally, the development of subterranean rivers in the South China Karst region was determined. Based on the results, the following conclusions can be drawn: the development of the subterranean rivers is indeed a slow process, but water quality can change rapidly in response to the transformation of industrial society. Additionally, the results indicate the crucial importance of urban planning that takes into account environmental protection during development in karst regions. This study aims to provide a basis for the management of karst areas and the improvement of groundwater quality by evaluating geochemical processes.
Existence of a Conserved Quantity and Stability of In Vitro Virus Infection Dynamics Models with Absorption Effect
Authors: Martínez-Lázaro Celia , Taneco-Hernández Marco Antonio , Reyes-Carreto Ramón , Vargas-De-León Cruz
Published: March 2019

The estimation of parameters in biomathematical models is useful to characterize quantitatively the dynamics of biological processes. In this paper, we consider some systems of ordinary differential equations (ODEs) modelling the viral dynamics in a cell culture. These models incorporate the loss of viral particles due to the absorption into target cells. We estimated the parameters of models by least-squares minimization between numerical solution of the system and experimental data of cell cultures. We derived a first integral or conserved quantity, and we proved the use of experimental data in order to test the conservation law. The systems have nonhyperbolic equilibrium points, and the conditions for their stability are obtained by using a Lyapunov function. We complemented these theoretical results with some numerical simulations.
Exploiting Temporal and Spatial Regularities for Content Dissemination in Opportunistic Social Network
Authors: Li Zhiyuan , Bi Junlei , Borrego Carlos
Published: March 2019

Recently, content dissemination has become more and more important for opportunistic social networks. The challenges of opportunistic content dissemination result from random movement of nodes and uncertain positions of a destination, which seriously affect the efficiency of content dissemination. In this paper, we firstly construct time-varying interest communities based on the temporal and spatial regularities of users. Next, we design a content dissemination algorithm on the basis of time-varying interest communities. Our proposed content dissemination algorithm can run in O(nlog⁡n) time. Finally, the comparisons between the proposed content dissemination algorithm and state-of-the-art content dissemination algorithms show that our proposed content dissemination algorithm can (a) keep high query success rate, (b) reduce the average query latency, (c) reduce the hop count of a query, and (d) maintain low system overhead.
Facile Interpretation of Catalytic Reaction between Organic Dye Pollutants and Silver Nanoparticles with Different Shapes
Authors: Cheon Ja Young , Kim Su Jun , Park Won Ho
Published: March 2019

In this study, various shapes of silver nanoparticles (Ag NPs) were synthesized via simple methods in aqueous solution. The size and shape of Ag NPs were measured by TEM image and DLS, and the crystalline form of Ag NPs was confirmed by XRD. From ATR-IR and zeta potential, the Ag NPs were found to be well surrounded by PVP. In addition, the catalytic activity of Ag NPs was evaluated using model dyes. Unlike the conventional catalysts, the model dyes with absorption peaks that did not overlap with the SPR peaks of the Ag NPs were selected to evaluate the catalytic activity without removal of the Ag NPs from the dye solution.
FOXO1 Overexpression Attenuates Tubulointerstitial Fibrosis and Apoptosis in Diabetic Kidneys by Ameliorating Oxidative Injury via TXNIP-TRX
Authors: Ji Linlin , Wang Qingzhu , Huang Fengjuan , An Tingting , Guo Feng , Zhao Yanyan , Liu Yang , He Yanyan , Song Yi , Qin Guijun
Published: March 2019

Objective. The generation of hyperglycemia-induced reactive oxygen species (ROS) is a key event in diabetic nephropathy (DN) development. Since forkhead box class O1 (FOXO1) is associated with oxidative stress and shows a positive effect on DN, its role on renal function and the underlying mechanism is still unclear. Methods. We examined the role of FOXO1 in vivo (in a transgenic diabetic mouse model overexpressing Foxo1) and in vitro (in human HK-2 cells with FOXO1 knockin (KI) and knockout (KO) cultured under high glucose). Results. Renal proximal tubular cells of kidney biopsies from patients with DN showed tubulointerstitial fibrosis and apoptosis. Accordingly, these proximal tubular injuries were accompanied by the increase of ROS generation in diabetic mice. Tissue-specific Foxo1 overexpression in transgenic mice had a protective effect on the renal function and partially reversed tubular injuries by attenuating the diabetes-induced increase in TXNIP and decrease in the TRX levels. FOXO1 knockin and knockout HK-2 cells were constructed to identify the associations between FoxO1 and TXNIP-TRX using CRISPR/CAS9. Similarly, the effects of FOXO1 KI and KO under high glucose were significantly modulated by the treatment of TRX inhibitor PX-12 and TXNIP small interfering RNA. In addition, TXNIP and TXN were identified as the direct FOXO1 transcriptional targets by chromatin immunoprecipitation. Conclusion. The regulatory role of FOXO1/TXNIP-TRX activation in DN can protect against the high glucose-induced renal proximal tubular cell injury by attenuating cellular ROS production. Modulating the FOXO1/TXNIP-TRX pathway may be a new therapeutic target in DN.
Catalytic Properties of Phosphate-Coated CuFe2O4 Nanoparticles for Phenol Degradation
Authors: Othman Israa , Abu Haija Mohammad , Banat Fawzi
Published: March 2019

Copper ferrite (CuFe2O4) nanoparticles were prepared using the sol-gel autocombustion method and then coated with phosphate using different treatments with H3PO4. The structural and chemical properties of the phosphate-coated CuFe2O4 nanoparticles were controlled by changing the concentration of H3PO4 during the coating process. The prepared nanoparticles were characterized using XRD, FTIR, SEM, and EDS which provided information about the catalysts’ structure, chemical composition, purity, and morphology. The catalytic and photocatalytic activities of the phosphate-coated CuFe2O4 samples were tested and evaluated for the degradation of phenol using HPLC. The prepared nanoparticles successfully emerged as excellent heterogeneous Fenton-type catalysts for phenol degradation. The phosphate-coated CuFe2O4 catalysts exhibited a higher catalytic activity compared with the uncoated CuFe2O4 ones. Such a higher catalytic performance can be attributed to enhanced morphological, electronic, and chemical properties of the phosphate-coated CuFe2O4 nanoparticles. Additionally, the phosphate-coated CuFe2O4 nanoparticles also revealed a higher catalytic activity compared with TiO2 nanoparticles. Different experimental conditions were investigated, and complete removal of phenol was achieved under specific conditions.
A Case of Rheumatoid Arthritis Presenting with Renal Thrombotic Microangiopathy Probably due to a Combination of Chronic Tacrolimus Arteriolopathy and Severe Hypertension
Authors: Honma Fumika , Fujigaki Yoshihide , Nemoto Yoshikazu , Kikuchi Hirotoshi , Nagura Michito , Arai Shigeyuki , Ishizawa Kenichi , Yamazaki Osamu , Tamura Yoshifuru , Kondo Fukuo , Ohashi Ryuji , Uchida Shunya , Shibata Shigeru
Published: March 2019

A 51-year-old woman with rheumatoid arthritis presented with mild hypertension 20 months after tacrolimus treatment and developing proteinuria 24 months after the treatment. Tacrolimus was discontinued 27 months after the treatment, followed by heavy proteinuria, accelerated hypertension, and deteriorating renal function without ocular fundus lesions as a clinical sign of malignant hypertension. Renal biopsy revealed malignant nephrosclerosis characterized by subacute and chronic thrombotic microangiopathy (TMA), involving small arteries, arterioles, and glomeruli. Focal segmental glomerulosclerosis, probably secondary to chronic TMA, was identified as a cause of heavy proteinuria. The zonal tubulointerstitial injury caused by subacute TMA may have mainly contributed to deteriorating renal function. The presence of nodular hyalinosis in arteriolar walls was indicative of tacrolimus-associated nephrotoxicity. Together with other antihypertensive drugs, administration of aliskiren stabilized renal function with reducing proteinuria. Owing to the preexisting proteinuria prior to severe hypertension and the complex renal histopathology, we postulated that chronic TMA, which was initially triggered by tacrolimus, was aggravated by severe hypertension, resulting in overt renal TMA.
Rainbow Connectivity Using a Rank Genetic Algorithm: Moore Cages with Girth Six
Authors: Cervantes-Ojeda J. , Gómez-Fuentes M. , González-Moreno D. , Olsen M.
Published: March 2019

Arainbowt-coloringof at-connected graphGis an edge coloring such that for any two distinct verticesuandvofGthere are at leasttinternally vertex-disjoint rainbow(u,v)-paths. In this work, we apply a Rank Genetic Algorithm to search for rainbowt-colorings of the family of Moore cages with girth six(t;6)-cages. We found that an upper bound in the number of colors needed to produce a rainbow 4-coloring of a(4;6)-cage is 7, improving the one currently known, which is 13. The computation of the minimum number of colors of a rainbow coloring is known to be NP-Hard and the Rank Genetic Algorithm showed good behavior finding rainbowt-colorings with a small number of colors.
Correlation of Serum 1,5-AG with Uric Acid in Type 2 Diabetes Mellitus with Different Renal Functions
Authors: Zhang Kai , Xue Bizhen , Yuan Yuexing , Wang Yao
Published: March 2019

Aim. Recent studies found that levels of serum uric acid (SUA) were positively associated with serum 1,5-anhydroglucitol (1,5-AG) in subjects with type 2 diabetes mellitus (T2DM). In the current study, we investigated the association between 1,5-AG and UA in T2DM patients with different renal functions.Methods. A total of 405 T2DM patients, 213 men and 192 women, participated in the study. Patients’ clinical information was collected, and serum 1,5-AG, SUA, and other clinical characteristics were measured. Correlation analyses were carried out to analyze their correlation with serum 1,5-AG and SUA.Results. The male group showed higher levels of SUA than the female group (282.1 ± 91.2 and 244.7 ± 71.89 μmol/L, respectively,P<0.01). Pearson’s correlation coefficients determine that SUA was positively associated with 1,5-AG in both men (r=0.213,P<0.05) and women (r=0.223,P<0.05), and such relationship can be influenced by the renal function. The positive association still existed with moderate impaired renal function. Moreover, 1,5-AG had a negative association with haemoglobin A1c (HbA1c) in T2DM subjects with eGFR ≥ 30 mL/min/1.73 m2(P<0.01).Conclusion. The positive association between SUA and 1,5-AG still exists in T2DM with moderate renal failure. 1,5-AG can still reflect the glucose levels in patients with CKD stages 1-3.
Autopilot Design for a Compound Control Small-Scale Solid Rocket in the Initial Stage of Launch
Authors: Dong Tian , Zhao Changjian , Song Zhiguo
Published: March 2019

In this paper, an autopilot design method for a compound control small-scale solid rocket is proposed. The rocket has multiple actuators, including a flexible nozzle for pitching and yawing channels, aerodynamic fins for rolling channel, and lateral thrusters which work in on-off mode for all three channels. In order to keep the aircraft steady in the initial stage of launch when the dynamic pressure is low, the autopilot is aimed at optimizing the cooperation among the actuators. Firstly, without considering the discontinuous lateral thrust, the control law for flexible nozzle and aerodynamic fins is achieved via the sliding mode control approach. On this basis, an object to be controlled with choiceness is obtained for the lateral thrusters controlled loop. Secondly, the operation logic of lateral thrusters is programmed, regarding rolling moment as priority. Thirdly, after a continuous controller is obtained, a discretization method for the lateral thrusters control law is designed combining the characteristics of sliding mode control and Lyapunov’s stableness theorem. Finally, the fundamental cause why compound control improves the system stability is given theoretically. Simulation results validate the improved response performance and robustness against uncertainties and disturbance of the autopilot.
Reconstructing Paleofluid Circulation at the Hercynian Basement/Mesozoic Sedimentary Cover Interface in the Upper Rhine Graben
Authors: Dezayes Chrystel , Lerouge Catherine
Published: March 2019

In this paper, we focus on paleocirculation at the Hercynian basement/sedimentary cover interface in the tectonic environment of the Upper Rhine graben. The goal is to increase our understanding of the behavior of the fracture-fault network and the origin of the hydrothermal fluids. We studied orientations, mineral fillings, and fluid origins of fractures that crosscut the Hercynian granitic basement and the Permo-Triassic formations in relation to the major tectonic events. Because the Mesozoic formations and the Hercynian basement on the graben flanks and inside the graben do not have the same evolution after uplift, our study includes 20 outcrops on both graben flanks and cores of the Soultz-sous-Forêts geothermal wells located inside the graben. The Hercynian granitic basement and Permo-Triassic formations were affected by several brittle phases associated with fluid circulation pulses related to graben formation during the Tertiary. We distinguished at least four stages: (1) reactivation of Hercynian structures associated with pre-rift tectonics during the early Eocene and descending meteoric waters, characterized by shearing/cataclasis textures and precipitation of illite and microquartz; (2) initiation of convective circulation of deep hot brines mixed with descending meteoric waters at the Hercynian basement/sedimentary cover interface during this first stage of Eocene rifting, characterized by dolomite and barite fillings in reactivated Hercynian fractures; (3) N-S tension fractures associated with rift tectonics just prior to uplift of the graben shoulders during Oligocene extension and descending meteoric waters, characterized by cataclastic textures and precipitation of quartz, illite, hematite, and barite; and (4) current convective circulation of deep hot brines mixed with descending meteoric waters at the Hercynian basement/sedimentary cover interface, characterized by calcite and barite fillings within the graben. This convective circulation is today present in deep geothermal wells in the western part of the Rhine graben.
Using Morphological Data in Language Modeling for Serbian Large Vocabulary Speech Recognition
Authors: Pakoci Edvin , Popović Branislav , Pekar Darko
Published: March 2019

Serbian is in a group of highly inflective and morphologically rich languages that use a lot of different word suffixes to express different grammatical, syntactic, or semantic features. This kind of behaviour usually produces a lot of recognition errors, especially in large vocabulary systems—even when, due to good acoustical matching, the correct lemma is predicted by the automatic speech recognition system, often a wrong word ending occurs, which is nevertheless counted as an error. This effect is larger for contexts not present in the language model training corpus. In this manuscript, an approach which takes into account different morphological categories of words for language modeling is examined, and the benefits in terms of word error rates and perplexities are presented. These categories include word type, word case, grammatical number, and gender, and they were all assigned to words in the system vocabulary, where applicable. These additional word features helped to produce significant improvements in relation to the baseline system, both for n-gram-based and neural network-based language models. The proposed system can help overcome a lot of tedious errors in a large vocabulary system, for example, for dictation, both for Serbian and for other languages with similar characteristics.
Inequality of Ostrowski Type for Mappings with Bounded Fourth Order Partial Derivatives
Authors: Alshanti Waseem Ghazi
Published: March 2019

A general Ostrowski’s type inequality for double integrals is given. We utilize function whose partial derivative of order four exists and is bounded.
Different Responses to Drug Safety Screening Targets between Human Neonatal and Infantile Heart Tissue and Cardiac Bodies Derived from Human-Induced Pluripotent Stem Cells
Authors: Trieschmann Jan , Haustein Moritz , Köster Annette , Hescheler Jürgen , Brockmeier Konrad , Bennink Gerardus , Hannes Tobias
Published: March 2019

Aims. Induced pluripotent stem cell-derived cardiomyocytes (iPS-CMs) have become a promising tool in cardiovascular safety pharmacology. Immaturity of iPS-CMs remains an ongoing concern. We compared electrophysiological and contractile features of cardiac bodies (hiPS-CBs) derived from human-induced pluripotent stem cells and human neonatal and infantile myocardial slices relevant for drug screening. Methods and Results. Myocardial tissue slices were prepared from biopsies obtained from patients undergoing surgery for hypoplastic left heart syndrome (HLHS) and tetralogy of Fallot (TOF). Electrophysiological features and response to Ik,r blockade as well as contractile properties were investigated using microelectrodes and isometric force measurements and were compared to hiPS-CBs. Both native myocardial tissue slices as well as hiPS-CBs showed action potential prolongation after Ik,r blockade, but early afterdepolarisations could be observed in native myocardial tissue slices only. The force-frequency relationship (FFR) varied at lower frequencies and was negative throughout at higher frequencies in hiPS-CBs. In contrast, native myocardial tissue slices exhibited positive, negative, and biphasic FFRs. In contrast to native myocardial tissue slices, hiPS-CBs failed to show an inotropic response to ß-adrenergic stimulation. Although all groups showed ß-adrenergic induced positive lusitropy, the effect was more pronounced in myocardial tissue slices. Conclusion. hiPS-CBs were able to reproduce AP prolongation after Ik,r blockade, but to a lesser extent compared to human neonatal and infantile myocardial tissue slices. Early afterdepolarisations could not be induced in hiPS-CBs. Contractile force was differently regulated by β-adrenergic stimulation in hiPS-CBs and the native myocardium. If used for cardiotoxicity screening, caution is warranted as hiPS-CBs might be less sensitive to pharmacologic targets compared to the native myocardium of neonates and infants.
Esophageal Impedance-pH Monitoring and Pharyngeal pH Monitoring in the Diagnosis of Extraesophageal Reflux in Children
Authors: Plocek Anna , Gębora-Kowalska Beata , Białek Jakub , Fendler Wojciech , Toporowska-Kowalska Ewa
Published: March 2019

Various clinical symptoms are attributed to extraesophageal reflux disease (EERD). Multichannel intraluminal impedance-pH monitoring (MII-pH) is considered to correlate symptoms with acid and nonacid gastroesophageal reflux (GER) events. Pharyngeal pH monitoring (Dx-pH) is considered to correlate the decrease in the pH level in the oropharynx with reported symptoms and to diagnose supraesophageal reflux. We aimed to assess the correlation between acid reflux episodes recorded by Dx-pH and GER detected via MII-pH in children with suspected EERD. The study enrolled 23 consecutive children (15 boys and 8 girls; median age 8.25 [range 3-16.5] years) with suspected EERD. MII-pH and Dx-pH were conducted concurrently in all patients. A total of 1228 reflux episodes were recorded by MII-pH. With the antimonic sensor placed inside the impedance probe, 1272 pH-only reflux episodes were recorded. Of these, 977 (76.81%) were associated with a retrograde bolus transit. Regarding GER, 630 full-column episodes extended to the most proximal pair of impedance sensors; 500 (83.33%) demonstrated an acidic character. The following acid reflux numbers were determined by the Dx-pH system: forpH<4,n=126;pH<4.5,n=136;pH<5,n=167; andpH<5.5,n=304, and for a decrease inpH>10%relative to the baseline,n=324. There was no significant correlation between the number of pharyngeal reflux episodes detected by Dx-pH and that of GERs identified by MII-pH. The proportion of oropharyngeal pH events that were temporally related to a GER episode increased with the extended pH criteria. The highest proportion was observed for a pH decrease of ≥10% from the baseline and did not exceed 5.2%. The application of the extended pH criteria in the Dx-pH system resulted in an increase in the number of diagnosed laryngopharyngeal refluxes; most were not temporally associated with GER episodes confirmed by MII-pH. Thus, the efficacy of the exclusive application of Dx-pH for supraesophageal gastric reflux diagnosis is uncertain.
A Comprehensive Analysis of the Changes in Precipitation Patterns over Beijing during 1960–2012
Authors: Song Xiaomeng , Zhang Jianyun , Zhang Chunhua , Zou Xianju
Published: March 2019

Precipitation pattern has changed over many regions in recent decades, which may cause the risk of flood or drought. In this study, the main objective is to evaluate the spatiotemporal variability of precipitation in Beijing from 1960 to 2012. First, the mean monthly, seasonal, and annual precipitation series were used to analyze the temporal variation using regression, Mann–Kendall (M-K) test, Sen’s slope, and Pettitt tests. The results showed that the annual mean precipitation had a clear decreasing trend, with the statistically significant decrease in summer (especially in July and August) and significant increase in spring (especially in May). Although the decreasing trend is shown in the precipitation concentration indicators, the temporal uneven distribution of precipitation has unchanged. Subsequently, the precipitation time series at 30 stations over Beijing were used to evaluate the changes in precipitation pattern. The results showed that the annual series for the most rain gauges had decreasing trends with gradual changes. The spatial distribution of precipitation and other indices is geographically consistent, reflecting the principal physiographic and climatic conditions. At the same time, the effects of the terrain and urban development on the precipitation spatial distribution were detected. Generally, the large and heavy precipitations frequently occur in the plain areas, while the precipitation in the mountain areas is dominated by the small and medium precipitation. As a whole, the total precipitation in the plain areas (558.8 mm) was slightly higher than that in the mountainous areas (533.0 mm), while the precipitation in the urban areas (575.9 mm) was much higher than in the surrounding suburb areas (538.9 mm) during 1960–2012. The differences between the plain and mountainous areas during the period of 1960–1979, 1980–1999, and 2000–2012 were 24.2 mm, 32.6 mm, and 17.7 mm, respectively. The differences in precipitation between the urban and suburb areas for the three periods were 32.9 mm, 45.2 mm, and 31.0 mm, respectively, with the amount accounting for 5.51%, 7.66%, and 5.94% of the mean precipitation in the urban areas for the corresponding periods.
Characterization of Evolutionarily Conserved Trypanosoma cruzi NatC and NatA-N-Terminal Acetyltransferase Complexes
Authors: Ochaya Stephen , Franzén Oscar , Buhwa Doreen Asiimwe , Foyn Håvard , Butler Claire E. , Stove Svein Isungset , Tyler Kevin M. , Arnesen Thomas , Matovu Enock , Åslund Lena , Andersson Björn
Published: March 2019

Protein N-terminal acetylation is a co- and posttranslational modification, conserved among eukaryotes. It determines the functional fate of many proteins including their stability, complex formation, and subcellular localization. N-terminal acetyltransferases (NATs) transfer an acetyl group to the N-termini of proteins, and the major NATs in yeast and humans are NatA, NatB, and NatC. In this study, we characterized the Trypanosoma cruzi (T. cruzi) NatC and NatA protein complexes, each consisting of one catalytic subunit and predicted auxiliary subunits. The proteins were found to be expressed in the three main life cycle stages of the parasite, formed stable complexes in vivo, and partially cosedimented with the ribosome in agreement with a cotranslational function. An in vitro acetylation assay clearly demonstrated that the acetylated substrates of the NatC catalytic subunit from T. cruzi were similar to those of yeast and human NatC, suggesting evolutionary conservation of function. An RNAi knockdown of the Trypanosoma brucei (T. brucei) NatC catalytic subunit indicated that reduced NatC-mediated N-terminal acetylation of target proteins reduces parasite growth.
Environmental Chemistry and Ecotoxicology of Hazardous Heavy Metals: Environmental Persistence, Toxicity, and Bioaccumulation
Authors: Ali Hazrat , Khan Ezzat , Ilahi Ikram
Published: March 2019

Heavy metals are well-known environmental pollutants due to their toxicity, persistence in the environment, and bioaccumulative nature. Their natural sources include weathering of metal-bearing rocks and volcanic eruptions, while anthropogenic sources include mining and various industrial and agricultural activities. Mining and industrial processing for extraction of mineral resources and their subsequent applications for industrial, agricultural, and economic development has led to an increase in the mobilization of these elements in the environment and disturbance of their biogeochemical cycles. Contamination of aquatic and terrestrial ecosystems with toxic heavy metals is an environmental problem of public health concern. Being persistent pollutants, heavy metals accumulate in the environment and consequently contaminate the food chains. Accumulation of potentially toxic heavy metals in biota causes a potential health threat to their consumers including humans. This article comprehensively reviews the different aspects of heavy metals as hazardous materials with special focus on their environmental persistence, toxicity for living organisms, and bioaccumulative potential. The bioaccumulation of these elements and its implications for human health are discussed with a special coverage on fish, rice, and tobacco. The article will serve as a valuable educational resource for both undergraduate and graduate students and for researchers in environmental sciences. Environmentally relevant most hazardous heavy metals and metalloids include Cr, Ni, Cu, Zn, Cd, Pb, Hg, and As. The trophic transfer of these elements in aquatic and terrestrial food chains/webs has important implications for wildlife and human health. It is very important to assess and monitor the concentrations of potentially toxic heavy metals and metalloids in different environmental segments and in the resident biota. A comprehensive study of the environmental chemistry and ecotoxicology of hazardous heavy metals and metalloids shows that steps should be taken to minimize the impact of these elements on human health and the environment.
Traditional Salads and Soups with Wild Plants as a Source of Antioxidants: A Comparative Chemical Analysis of Five Species Growing in Central Italy
Authors: Savo Valentina , Salomone Francois , Mattoni Elena , Tofani Daniela , Caneva Giulia
Published: March 2019

The interest and demand for nutraceuticals are rapidly increasing in many industrialized countries due to the emergence of health risks associated with the increased consumption of processed foods. Several wild Mediterranean plants used as traditional foods are an extraordinary source of nutraceutical substances with antioxidant properties. This study has two main aims:(1)to quantify the antioxidant properties of traditional wild food plants and(2)to determine if their use in soups (i.e., the cooking process) can alter their beneficial properties. We have evaluated the antioxidant capacity (ABTS, DPPH) and the Total Phenolic Content (Folin-Ciocalteu) of five herbaceous plants traditionally consumed in several areas of Central Italy: (A)Reichardia picroides(L.) Roth, (B)Hypochaeris radicataL., (C)Cichorium intybusL., (D)Tordylium apulumL., and (E)Helminthotheca echioides(L.) Holub. Our analyses show good levels of antioxidant capacity for all plants, withReichardia picroidesandHelminthotheca echioideshaving the highest levels. There is a high correlation between the antioxidant activity and the Total Phenolic Content especially inReichardia picroides(R2=0.92) andHypochaeris radicata(R2=0.93). Boiling the species caused a general decrease in the antioxidant activity and polyphenols. Our study confirms the health benefits of consuming wild plants, especially raw ones in salads. It also supports the use of ethnobotanical information to study and then promote the consumption of wild food plants.
Dynamic Mechanical Characteristics and Constitutive Modeling of Rail Steel over a Wide Range of Temperatures and Strain Rates
Authors: Liu Peijie , Quan Yanming , Ding Guo
Published: March 2019

Rail steel plays an indispensable role in the safety and stability of the railway system. Therefore, a suitable constitutive model is quite significant to understand the mechanical behavior of this material. Here, the compressive mechanical behavior of heat-treated U71Mn rail steel over a wide range of strain rates (0.001 s−1–10000 s−1) and temperatures (20°C–800°C) was systematically investigated via uniaxial quasistatic and dynamic tests. The split Hopkinson pressure bar (SHPB) apparatus was utilized to perform dynamic mechanical tests. The effects of temperature, strain, and strain rate on the dynamic compressive characteristics of U71Mn were discussed, respectively. The results indicate that the flow response of U71Mn is both temperature-sensitive and strain rate-sensitive. However, the influence of temperature on the flow response is more remarkable than that of strain rate. On the basis of the experimental data, the original and modified Johnson-Cook (JC) models of the studied material were established, respectively. Using correlation coefficient and average absolute relative error parameters, it is revealed that better agreement between the experimental and predicted stress is reached by the modified JC model, which demonstrates that the modified one can characterize the mechanical behavior of the studied material preferably.
Experimental Strategies of Mesenchymal Stem Cell Propagation: Adverse Events and Potential Risk of Functional Changes
Authors: Drela Katarzyna , Stanaszek Luiza , Nowakowski Adam , Kuczynska Zuzanna , Lukomska Barbara
Published: March 2019

Mesenchymal stem cells (MSCs) are attractive candidates for cell-based tissue repair approaches. Hundreds of clinical trials using MSCs have been completed and many others are still being investigated. For most therapeutic applications, MSC propagation in vitro is often required. However, ex vivo culture condition is not fully physiological and may affect biological properties of MSCs including their regenerative potential. Moreover, both cell cryopreservation and labelling procedure prior to infusion may have the negative impact on their expected effect in vivo. The incidence of MSC transformation during in vitro culture should be also taken into consideration before using cells in stem cell therapy. In our review, we focused on different aspects of MSC propagation that might influence their regenerative properties of MSC. We also discussed the influence of different factors that might abolish MSC proliferation and differentiation as well as potential impact of stem cell senescence and aging. Despite of many positive therapeutic effects of MSC therapy, one has to be conscious about potential cell changes that could appear during manufacturing of MSCs.
Sequelae of Acute Respiratory Distress Syndrome: Interest of Rehabilitation
Authors: Godeau Elise , Debeaumont David , Artaud-Macari Elise , Lagache Laurie , Bouar Gurvan Le , Coquart Jérémy
Published: March 2019

Case Presentation. This clinical case presents the history of a woman hospitalized for acute respiratory distress syndrome (ARDS). A 62-year-old woman, with regular physical activity and no history of respiratory disease or smoking, was hospitalized for moderate ARDS with bilateral pneumonitis. Fourteen days later, she was discharged from the intensive care unit and received respiratory physical therapy. One month later, she experienced exertional dyspnea. A regression of alveolar condensation with persistent sequelae at the pulmonary bases was noted. Three months later, the patient continued daily physical activity with satisfactory tolerance. A reduction in alveolar-capillary transfer, inappropriate hyperventilation upon exercise, and impairment of gas exchanges at maximal effort, suggestive of pulmonary shunt, were demonstrated. At the 6-month evaluation, the patient displayed exertional dyspnea with residual bilateral basal consolidations. Six months later, the dyspnea had ceased. The persistence of bilateral basal interstitial syndrome associated with bronchial dilatation and pleural-based consolidations was noted, as well as a stable impaired alveolar-capillary diffusing capacity. Discussion. Upon discharge from intensive care, pulmonary follow-up should be proposed to ARDS survivors. Moreover, pulmonary function testing at rest and exercise is advised as soon as possible to evaluate the respiratory sequelae. This will help to limit the severity of complications through adapted exercise rehabilitation and then regular physical activity.
Vertebral Fractures among Patients Referred for Bone Densitometry Screening in Dubai Primary Health Care Facilities
Authors: Alshaali Anood Jamal , Abd El Aal Soha Abd El Aziz , AlJaziri Amal Mohamad , Abdellatif Tamer Mohamed Farid , Taryam Manal Mohammad Omran , Monsef Nahed AbdulKhaleq
Published: March 2019

Vertebral fractures are one of the most common fractures associated with low bone mineral density. However two-thirds to three-fourths of patients with vertebral fractures are not clinically recognized. The objective of this study was to determine the prevalence of vertebral fractures in patients referred for bone densitometry and the most common site of fracture. The study was carried out in the osteoporosis clinic in Dubai primary health care center. A total of 120 patients were examined using the dual energy X-ray absorptiometry. Of all the patients, 48.3% were osteoporotic and 40.9% were osteopenic. The overall prevalence of vertebral fracture was 14.2%. The result showed that the prevalence of vertebral fracture was higher in female compared to male (15.7% and 9.7%, respectively). It was found that patients aged 80 and above had the highest prevalence of vertebral fracture (54.5%). Undiagnosed vertebral fractures were common. Therefore, it is crucial to prevent vertebral fracture through early diagnosis and appropriate treatment of osteoporosis.
Hypoglossal Nerve Palsy as a Cause of Severe Dysphagia along with the Oropharyngeal Stenosis due to Occipitocervical Kyphosis
Authors: Watanabe Tomohiro , Anno Masato , Matsubayashi Yoshitaka , Nagasako Yuki , Sakuishi Kaori , Fujimoto Yoh , Tachibana Naohiro , Taniguchi Yuki , Hayashi Toshihiro , Oshima Yasushi , Tsuji Shoji , Tanaka Sakae
Published: March 2019

Hypoglossal nerve palsy (HNP) is a potential cause of dysphagia. A 66-year-old man presented to our hospital with dysphagia and neck pain. One year prior to his first visit, he had been diagnosed with upper cervical tuberculosis and had undergone posterior C1-2 fixation. The physical examination led to the diagnosis of dysphagia with HNP, and he had severe weight loss. Radiographic examination revealed that the O-C kyphosis had been exacerbated and that the deformity was likely the primary cause of HNP. To restore the swallowing function, O-C fusion surgery was performed. Postoperatively, the patient showed immediate improvement of dysphagia with gradual recovery of hypoglossal nerve function. In the last follow-up evaluation, swallowing function was confirmed with no signs of HNP. Our results indicate that HNP could be more prevalent in cases with severe cervical kyphosis, being underdiagnosed due to the more apparent signs of the oropharyngeal narrowing.
Sarcopenia and Its Implications for Metabolic Health
Authors: Hunter Gary R. , Singh Harshvardhan , Carter Stephen J. , Bryan David R. , Fisher Gordon
Published: March 2019

Sarcopenia not only affects the ability to lead an active lifestyle but also contributes to increased obesity, reduced quality of life, osteoporosis, and metabolic health, in part due to reduced locomotion economy and ease. On the other hand, increased obesity, decreased quality of life, and reduced metabolic health also contribute to sarcopenia. The purpose of this mini-review is to discuss the implications sarcopenia has for the development of obesity and comorbidities that occur with aging.
Analysis of Enamel Loss by Prophylaxis and Etching Treatment in Human Tooth Using Optical Coherence Tomography: An In Vitro Study
Authors: Ravichandran Naresh Kumar , Tumkur Lakshmikantha Hemanth , Park Hyo-sang , Jeon Mansik , Kim Jeehyun
Published: March 2019

Bonding of braces is an essential part in contemporary orthodontic treatment. For the proper strength of bracket bonding, enamel conditioning or surface treatment on tooth surface is required. Treatment on the tooth surface such as prophylaxis smoothing with pumice and enamel etching results in considerable damages to the enamel surface of the tooth. In this study, we have proposed optical coherence tomography as a noninvasive imaging technique for the evaluation of damage induced during such treatment procedures. Using depth intensity analysis of the obtained cross-sectional images, the damage resulting to the enamel surface was studied after prophylaxis smoothening and etching steps.
Design Approaches of MEMS Microphones for Enhanced Performance
Authors: Shah Muhammad Ali , Shah Ibrar Ali , Lee Duck-Gyu , Hur Shin
Published: March 2019

This paper reports a review about microelectromechanical system (MEMS) microphones. The focus of this review is to identify the issues in MEMS microphone designs and thoroughly discuss the state-of-the-art solutions that have been presented by the researchers to improve performance. Considerable research work has been carried out in capacitive MEMS microphones, and this field has attracted the research community because these designs have high sensitivity, flat frequency response, and low noise level. A detailed overview of the omnidirectional microphones used in the applications of an audio frequency range has been presented. Since the microphone membrane is made of a thin film, it has residual stress that degrades the microphone performance. An in-depth detailed review of research articles containing solutions to relieve these stresses has been presented. The comparative analysis of fabrication processes of single- and dual-chip omnidirectional microphones, in which the membranes are made up of single-crystal silicon, polysilicon, and silicon nitride, has been done, and articles containing the improved performance in these two fabrication processes have been explained. This review will serve as a starting guide for new researchers in the field of capacitive MEMS microphones.
Hybrid Modeling Method and Bifurcation Characteristics Analysis for Buck Converter with Constant Power Load
Authors: Huang Liangyu , Lu Yimin
Published: March 2019

We establish a novel hybrid model of a continuous conduction mode buck converter with a constant power load based on the mixed logical dynamical modeling method. Based on the proposed model, the influence of the constant power load’s negative impedance (RCPL) on the dynamics of the buck converter with a constant power load is studied by computing bifurcation diagrams and the spectrum of the largest Lyapunov exponents with the variation of the absolute value of RCPL. Numerical results show that the system’s bifurcations exhibit two different types of behavior, namely, Hopf bifurcations and state jumping. Moreover, the accuracy and effectiveness of the established mathematical model are verified via simulation and experimental results. Because of including different discrete mappings of the system exhibited in different working modes in a unified model, the proposed hybrid model solves the problem of choosing different discrete mappings according to different working models. That is, the hybrid model in this paper provides a new unified model for future research on the dynamic properties and design of controllers for such systems.
Stabilized Peptide HDAC Inhibitors Derived from HDAC1 Substrate H3K56 for the Treatment of Cancer Stem–Like Cells In Vivo
Authors: Wang Dongyuan , Li Wenjun , Zhao Rongtong , Chen Longjian , Liu Na , Tian Yuan , Zhao Hui , Xie Mingsheng , Lu Fei , Fang Qi , Liang Wei , Yin Feng , Li Zigang
Published: March 2019

FDA-approved HDAC inhibitors exhibit dose-limiting adverse effects; thus, we sought to improve the therapeutic windows for this class of drugs. In this report, we describe a new class of peptide-based HDAC inhibitors derived from the HDAC1-specific substrate H3K56 with improved nonspecific toxicity compared with traditional small-molecular inhibitors. We showed that our designed peptides exerted superior antiproliferation effects on cancer stem–like cells with minimal toxicity to normal cells compared with the small-molecular inhibitor SAHA, which showed nonspecific toxicity to normal and cancer cells. These peptide inhibitors also inactivated cellular HDAC1 and HDAC6 and disrupted the formation of the HDAC1, LSD1, and CoREST complex. In ovarian teratocarcinoma (PA-1) and testicular embryonic carcinoma (NTERA-2) cell xenograft animal models (5 mice/group, 50 mg/kg, every other day, intraperitoneal injection), these peptides inhibited tumor growth by 80% to 90% with negligible organ (heart, liver, spleen, lung, kidney, brain) lesions. These results represent the first attempt to design chemically stabilized peptide inhibitors to investigate HDAC inhibition in cancer stem–like cells. These novel peptide inhibitors have significantly enhanced therapeutic window and offer promising opportunities for cancer therapy.

Significance:

Selective antiproliferative effects of stabilized peptide HDAC inhibitors toward cancer stem–like cells provide a therapeutic alternative that avoids high nonspecific toxicity of current drugs.
A High Monocyte-to-Lymphocyte Ratio Predicts Poor Prognosis in Patients with Advanced Gallbladder Cancer Receiving Chemotherapy
Authors: Choi Young Hoon , Lee Jae Woo , Lee Sang Hyub , Choi Jin Ho , Kang Jinwoo , Lee Ban Seok , Paik Woo Hyun , Ryu Ji Kon , Kim Yong-Tae
Published: March 2019

Background:

Monocyte-to-lymphocyte ratio (MLR), neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR) have been reported to be prognostic markers in various cancers. However, the prognostic value of these inflammatory biomarkers, particularly MLR, in gallbladder cancer remains to be determined.

Methods:

From 2005 to 2016, 178 patients with histologically confirmed gallbladder adenocarcinoma who underwent palliative chemotherapy were queried in this study. The association between survival and various clinical and laboratory variables, including MLR, NLR, and PLR, was investigated. The optimal cutoff values for MLR, NLR, and PLR were determined using the maxstat package of R.

Results:

Patients with high MLR (>0.24) were expected to have shorter progression-free survival [PFS; hazard ratio (HR), 2.100; 95% confidence interval (CI), 1.397–3.157; P < 0.001] and overall survival (OS; HR, 2.533; 95% CI, 1.664–3.856; P < 0.001) compared with patients with low MLR (≤0.24). In multivariate Cox model, CA 19-9, stage, and MLR were independent factors for PFS. MLR was also an independent predictor of OS along with PLR, age, and CA 19-9, whereas NLR was not significantly associated with OS. Time-dependent receiver operating characteristic (ROC) analysis showed that the area under the curve of MLR for predicting OS was greater than that of NLR and PLR at most time points.

Conclusions:

MLR independently predicts survival in gallbladder cancer patients undergoing chemotherapy. Future prospective studies are needed to validate its value as a prognostic biomarker.

Impact:

MLR is an inexpensive and easily available biomarker for predicting prognosis in patients with gallbladder cancer undergoing chemotherapy.
Childhood Body Mass Index Is Associated with Risk of Adult Colon Cancer in Men: An Association Modulated by Pubertal Change in Body Mass Index
Authors: Célind Jimmy , Ohlsson Claes , Bygdell Maria , Nethander Maria , Kindblom Jenny M.
Published: March 2019

Background:

The relative contribution of childhood and pubertal body mass index (BMI) for the risk of adult colorectal cancer is not known. The aim of this study was to evaluate the independent associations for childhood BMI and pubertal BMI change with risk of colorectal cancer in men.

Methods:

We included 37,663 men born in 1946 to 1961 who had weight and height measured at 8 (childhood) and 20 (young adult age) years of age available from the BMI Epidemiology Study. Information on colorectal cancer was retrieved from the Swedish National Patient Register (257 cases of colon cancer and 159 cases of rectal cancer).

Results:

Childhood BMI at 8 years of age [HR, 1.19 per SD increase; 95% confidence interval (CI), 1.06–1.33], but not pubertal BMI change (HR, 1.02; 95% CI, 0.90–1.15), was associated with increased risk of colon cancer. Due to a significant interaction between childhood BMI and pubertal BMI change (P < 0.001), we stratified the analyses according to the median of pubertal BMI change. Childhood BMI was associated with risk of colon cancer in individuals with a pubertal BMI change above, but not below, the median (above: HR = 1.48, 95% CI, 1.26–1.74; below: HR = 0.95, 95% CI, 0.80–1.12). Neither childhood BMI nor pubertal BMI change was associated with rectal cancer.

Conclusions:

High childhood BMI was associated with increased risk of colon cancer only if it was followed by a pubertal BMI increase above the median.

Impact:

Further studies should evaluate prepubertal childhood BMI in relation to pubertal BMI change and BMI in middle age for the risk of colon cancer.