bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental investigation on flue gas purification and gas‐liquid multiphase flow in a spraying column with perforated plate
Authors: Chen Zhen , Jiang Zhiqiang , You Changfu , Wang Haiming
Published: December 2019

The synergetic removal of sulphur dioxide and particulate matters (PM) in flue gas was investigated in a spraying column equipped with flow pattern controlling (FPC) internals. The performance of the novel column was compared with that of the traditional open column by monitoring the removal efficiency and system pressure drop. To understand the gas‐liquid multiphase flow field and mass transfer process inside the column with different structures, image processing based on the Otsu method and particle image velocimetry (PIV) technology were used. It was found that the FPC column with a section size of 200 mm × 200 mm, hole diameter of 4 mm, and aperture ratio of 0.65 demonstrated the best performance. As clearly observed from the flow filed, bubble flow was formed in FPC column, while the dispersive and falling‐film flow was developed in the open column. The liquid holdup in FPC unit was much more than in the open spraying column, which enhanced the mass transfer process. According to the PIV results, the reverse flow of the liquid, caused by the gas jet ascribed to the perforated plate and the confined space in the FPC unit, was the primary reason for bubble generation and the gas‐liquid flow pattern in the column.
Study on wax precipitation characteristics of wax deposit in pipes
Authors: Gao Xuedong , Huang Qiyu , Zhang Xun , Li Weidong , Ren Yijie , Wang Junfang
Published: December 2019

Wax deposit properties are a significant concern in pipeline pigging during waxy crude oil transportation. In the present work, the impacts of flow conditions and oil properties on the wax precipitation characteristics of wax deposits are investigated. A flow loop apparatus was developed to conduct wax deposition experiments using four crude oils collected from different field pipes. The differential scanning calorimetry (DSC) technique was employed to observe the wax precipitation characteristics of crude oil and wax deposit. The results show that the wax content and the wax appearance temperature (WAT) of the deposits increase with shear stress and radial temperature gradient, and decrease with radial wax molecule concentration gradient near the pipe wall. The DSC tests on the wax deposits revealed that the deposit wax content is strongly correlated to the oil wax content. Furthermore, an empirical correlation was developed to predict the wax content and the WAT of the wax deposit. Verification of the empirical correlation using the different oils indicated that the average relative error of the wax content prediction and average absolute error of WAT prediction were 13.2% and 3.6°C, respectively.
Li4Ti5O12−TiO2 Composite Coated on Carbon Foam as Anode Material for Lithium Ion Capacitors: Evaluation of Rate Performance and Self‐Discharge
Authors: Zhou Huanhuan , Ma Qun , Yang Wei , Lu Xianmao
Published: December 2019

Li4Ti5O12‐TiO2 (LTO‐TO) composite is coated on carbon foam (CF) for anode of lithium ion capacitors (LICs). The resulting CF@LTO‐TO electrodes with varied mass loadings of LTO‐TO exhibit much improved rate performance compared to pristine LTO electrode. Specifically, asymmetric LICs based on activated carbon cathode and CF@LTO‐TO anode (AC//CF@LTO‐TO) with 25 wt% of LTO‐TO delivers a specific capacity of 65 mAh g−1 at 300 C. In addition, the self‐discharge rates of the LICs are evaluated. It is found that AC//CF@LTO‐TO LIC with 45 wt% of LTO‐TO shows much reduced self‐discharge rate (open circuit voltage drops from 2.5 to 1.1 V in 144 hours) relative to AC//CF@LTO‐TO with different LTO‐TO mass loadings. The results of this study suggest that the introduction of TO in LTO anode can affect both the rate performance and the self‐discharge behavior, which may be due to the fast faradaic reaction kinetic of TO and the rich LTO‐TO grain boundary interfaces.
Secure and privacy‐preserving keyword search retrieval over hashed encrypted cloud data
Authors: N Sathyabalaji , G Komarasamy , S Daniel Madan Raja
Published: December 2019

Cloud computing (CC) is the universal area in which the data owners will contract out their pertinent data to the untrusted public cloud that permits the data users to retrieve the data with complete integrity. To give data privacy along with integrity, majority of the research works were concentrated on single data owner for secure searching of encrypted data via the cloud. Also, searchable encryption supports data user to retrieve the particular encrypted document from encrypted cloud data via keyword search (KS). However, these researches are not efficient for keyword search retrieval. To trounce such drawbacks, this paper proposes efficient secure and privacy‐preserving keyword search retrieval (SPKSR) system, in which the user retrieves the hashed encrypted documents over hashed encrypted cloud data. The proposed system includes three entities explicitly, (a) data owner (DO), (b) cloud server (CS), and (c) data users (DU). The owner outsources hashed encrypted documents set, along with generated searchable index tree to the CS. The CS hoards the hashed encrypted document collection and index tree structure. DU performs the “search” over the hashed encrypted data. Experimental results of the proposed system are analyzed and contrasted with the other existent system to show the dominance of the proposed system.
Is part‐time special education beneficial for children at risk for reading difficulties? An example from Estonia
Authors: Soodla Piret , Tammik Valdar , Kikas Eve
Published: December 2019

This longitudinal quasi‐experimental study examined the general efficiency of part‐time special education for students at risk for reading difficulties in Estonian primary schools. Participants were selected from 464 students whose pre‐reading and reading skills were assessed for the study at the beginning of school. Eighty‐four of these children received part‐time special education support throughout the first grade (treatment group). Statistical matching was used to find a control group similar to the treatment group on pre‐reading skills and parental educational level but who did not receive extra help (control group; 84 children). Students' reading fluency and task persistence were assessed at the end of Grade 1 and Grade 2. Neither group differed in reading fluency nor task persistence at the end of either grade. Developmental trajectories of those treatment group children who received additional support only for reading and spelling difficulties did not differ from those who received this support for concurrent developmental disorders in addition to reading and spelling difficulties. Our findings indicate that a full‐year of special education support in the form of extra lessons without a prior diagnostic assessment, frequent progress monitoring, or focused interventions might not be an effective way to support children with reading difficulties.
Murine CD8 T‐cell functional avidity is stable in vivo but not in vitro: Independence from homologous prime/boost time interval and antigen density
Authors: Gilfillan Connie B. , Wang Chensu , Mohsen Mona O. , Rufer Nathalie , Hebeisen Michael , Allard Mathilde , Verdeil Grégory , Irvine Darrell J. , Bachmann Martin F. , Speiser Daniel E.
Published: December 2019

It is known that for achieving high affinity antibody responses, vaccines must be optimized for antigen dose/density, and the prime/boost interval should be at least 4 weeks. Similar knowledge is lacking for generating high avidity T‐cell responses. The functional avidity (FA) of T cells, describing responsiveness to peptide, is associated with the quality of effector function and the protective capacity in vivo. Despite its importance, the FA is rarely determined in T‐cell vaccination studies. We addressed the question whether different time intervals for short‐term homologous vaccinations impact the FA of CD8 T‐cell responses. Four‐week instead of 2‐week intervals between priming and boosting with potent subunit vaccines in C57BL/6 mice did not improve FA. Equally, similar FA was observed after vaccination with virus‐like particles displaying low versus high antigen densities. Interestingly, FA was stable in vivo but not in vitro, depending on the antigen dose and the time interval since T‐cell activation, as observed in murine monoclonal T cells. Our findings suggest dynamic in vivo modulation for equal FA. We conclude that low antigen density vaccines or a minimal 4‐week prime/boost interval are not crucial for the T‐cell's FA, in contrast to antibody responses.
Differences in antinociceptive signalling mechanisms following morphine and fentanyl microinjections into the rat periaqueductal gray
Authors: Morgan Michael M. , Tran Alexander , Wescom Rebecca L. , Bobeck Erin N.
Published: December 2019

Background

Morphine and fentanyl are two of the most commonly used opioids to treat pain. Although both opioids produce antinociception by binding to mu‐opioid receptors (MOR), they appear to act via distinct signalling pathways.

Objective

This study will reveal whether differences in morphine and fentanyl antinociception are the result of selective activation of G‐protein signalling and/or selective activation of pre‐ or postsynaptic MORs.

Methods

The contribution of each mechanism to morphine and fentanyl antinociception was assessed by microinjecting drugs to alter G‐protein signalling or block potassium channels linked to pre‐ and postsynaptic MORs in the ventrolateral periaqueductal gray (PAG) of male Sprague‐Dawley rats.

Results

Both morphine and fentanyl produced a dose‐dependent antinociception when microinjected into the PAG. Enhancement of intracellular G‐protein signalling by microinjection of the Regulator of G‐protein Signalling 4 antagonist CCG‐63802 into the PAG enhanced the antinociceptive potency of morphine, but not fentanyl. Microinjection of α‐dendrotoxin into the PAG to block MOR activation of presynaptic Kv+ channels caused a significant rightward shift in the dose–response curve of both morphine and fentanyl. Microinjection of tertiapin‐Q to block MOR activation of postsynaptic GIRK channels caused a larger shift in the dose–response curve for fentanyl than morphine antinociception.

Conclusions

These findings reveal different PAG signalling mechanisms for morphine and fentanyl antinociception. In contrast with fentanyl, the antinociceptive effects of morphine are mediated by G‐protein signalling primarily activated by presynaptic MORs.

Significance

Microinjection of the opioids morphine and fentanyl into the periaqueductal gray (PAG) produce antinociception via mu‐opioid receptor signalling. This study reveals differences in the signalling mechanisms underlying morphine and fentanyl antinociception in the PAG. In contrast with fentanyl, morphine antinociception is primarily mediated by presynaptic opioid receptors and is enhanced by blocking RGS proteins.
The impact of national integration policies on prejudice and psychological well‐being: The fundamental role of the clarity and coherence of integration policies
Authors: de la Sablonnière Roxane , Nugier Armelle , Kadhim Nada , Kleinlogel Emmanuelle P. , Pelletier‐Dumas Mathieu , Guimond Serge
Published: December 2019

Recent advances in social psychological research have shown that national integration policies influence how immigrants are perceived and treated by the mainstream population. However, the processes by which these policies come to have an impact on prejudice and well‐being of the general population are largely unknown. Moreover, past research has often relied on unrepresentative samples limiting generalizability. The present research proposes that when the national integration policies of a given society are perceived as clearly defined and coherent, they have a direct impact on the perceived cultural norm related to those national integration policies. In turn, the perceived cultural norm affects personal attitudes toward cultural norms (i.e., the degree to which individuals support a given policy), which influence the level of anti‐immigrant prejudice as well as psychological well‐being. Findings from two correlational studies with representative samples of the mainstream population conducted in France on the policy of secularism (N = 940) and in Québec on the policy of interculturalism (N = 912) supported the proposed theoretical model.
Fog‐cloud distributed intrusion detection and cooperation
Authors: Ghribi Saadia , Makhlouf Amel Meddeb , Zarai Faouzi , Guizani Mohsen
Published: December 2019

Cloud computing is becoming a promoted technology. Over the recent years, it has rapidly grown and its adoption is more and more increasing. Many enterprizes and organizations have immigrated their data to the cloud. However, the security of this technology is considered a serious barrier to guarantee the organizations' trust on it. Therefore, intrusion detection has been set as the best solution to secure the cloud platform. Thus, many research studies have been developed for the aim to create an effective and performing intrusion detection system suitable for the cloud environment. In this paper, we propose a new approach for cloud environment–based multilevel cooperation in terms of intrusion detection. It is based on the cooperation and the correlation between fog nodes at the beginning and then between fog and cloud technology. We also evaluate the performance and the efficiency of this proposed prototype in terms of detection rates and detection response to make real‐time detection in the whole cloud platform. The results show that the proposed architecture introduces low false positive rate compared to the existing hybrid intrusion detection approach in cloud computing (HIDCC) framework.
Morphology‐Controllable Synthesis and Growth Mechanism of 3D‐Hierarchical Pd/SnO2/Ni Foam (NF) as the Cathode for Al‐H2O2 Semi‐Fuel Cell
Authors: Sun L. , Li S. , He W. , Wen F.
Published: December 2019

A hierarchical 3D composite cathode (Pd/SnO2/NF) was designed and synthesized via electrode positing Pd nanoparticles on the nanoarrays consisting of SnO2 nanorods grown upright on the surface of Ni foam (NF). The influence of the adding rate of alcohol and the standing time of precursor on the morphology of SnO2 nanostructures was investigated. The growth mechanism of SnO2 nanorods was investigated and the influences of the morphology of SnO2 nanomaterials on the size and electrochemical properties of Pd catalysts were also discussed. The morphology of SnO2 nanomaterials changes from nanoclusters to nanorods, and both the diameters of the nanorods and Pd nanospheres decrease gradually with decreasing the adding rate of alcohol and prolonging the standing time of precursor. When the adding rate of alcohol is 0.022 mL s−1 and standing precursor for 15 min, the SnO2 nanorods with a rutile structure are vertically grown on the surface of Ni foam apart, and Pd nanospheres are electrodeposited on the top of SnO2 nanorods. The formation of hierarchical 3D structure is benefitting for fully exposing the active site of the Pd catalyst and increasing the specific surface area of the electrode, further improving the performance of the Al‐H2O2 semi‐fuel cell.
Effects of Compression on the Removal of Water Droplet from GDLs of PEM Fuel Cells
Authors: Shojaeefard M. H. , Molaeimanesh G. R. , Moqaddari M. R.
Published: December 2019

Proton‐exchange membrane fuel cells (PEMFCs) with a sound potential for employing in the propulsion systems of green vehicles are currently at a high stage of development. However, appropriate water management is crucial for further development of PEMFCs. In the current investigation, the role of gas diffusion layer (GDL) compression and wettability on the removal of a water droplet from different GDLs with dissimilar levels of compression (0%, 15%, 20%, and 25%) and wettability (contact angles of 80°, 105°, and 150°) is inspected by numerous 3D lattice Boltzmann simulations. The results of this study demonstrate that by increasing of compression level, the droplet ejection will be more probable. Besides, for hydrophobic GDLs (i.e., contact angles of 105° and 150°) adding compression will help the removal process, regardless of the compression amount. However, for the hydrophilic GDLs (contact angle of 80°) adding compression is not necessarily helpful.
Empirisches Prognosemodell zur Bestimmung der Festigkeitsentwicklung von Spritzbeton
Authors: Hammer Anna‐Lena , Thewes Markus , Galler Robert
Published: December 2019

Shotcrete is an essential support element in tunnelling. From the start of the hydration of shotcrete, it resists stresses and deformation. Therefore its time‐dependent material properties, in particular the strength development and stiffness development, are significant. With time, the early strength can affect the progress of rock pressure and the support resistance. In order to describe its mechanical material properties, there are models, mostly validated with data from dry‐mix shotcrete or older shotcrete mix designs. Continuous further development in additive technology has however considerable improved the performance of shotcrete in recent years. In this article, data from more recent test series and from practical projects are evaluated. Building on the evaluation of the strength curves, an empirical forecasting model is presented, which can be used for the qualitative estimation of shotcrete strength development.
Elektrische Erdung bei untertägigen Infrastrukturprojekten
Authors: Pichler Moritz , Fürnschuß Martin , Friedl Katrin , Schürhuber Robert , Schmautzer Ernst
Published: December 2019

Electrical earthing (grounding) is necessary for the proper operation of electrical systems, machines and electronic equipment in the event of a fault, for protection against lightning and personal injury, and for reasons of electromagnetic compatibility. Earthing is understood as ”making an electrical connection between a given point in a system or in an installation or in equipment and a local earth“. Electrical grounding systems are designed according to national and international standards, with some of these standards occupying a significant place in the legal hierarchy in Austria and being binding. Simple structures are designed using approximate formulas given in the literature and standards; more complex arrangements use programs with analytical or numerical models for the calculation and design of grounding systems. Underground infrastructure projects require additional considerations. Starting with the technical and legal requirements, the typical process steps for the design of electrical grounding systems are shown.
Wechselwirkungen zwischen tiefliegendem Tunnelvortrieb und bestehendem Tunnel im Bereich von Störzonen – Modellierung versus Realität
Authors: Cordes Tobias , Weifner Tassilo , Unteregger David , Bergmeister Konrad
Published: December 2019

The influence of a tunnel drive on an existing tunnel is primarily the result of the tunnel geometries, the relative location of the two tunnels, the geological‐geomechanical conditions and the associated primary stress state. During construction of the Brenner Base Tunnel, there are constructionally relevant interactions in some places between the running tunnels and the exploratory tunnel (EKS) running centrally and 12 m deeper. The rock mass stress as a result of driving the running tunnels here leads to deformations of the previously driven exploratory tunnel. Due to the high loading on the outer linings of deep tunnels and the high stiffness of the already hardened shotcrete support, slight deformation can cause local cracking in the support layer. This article compares the observed deformations in a fault zone intersecting at a flat angle with numerical simulations, which enables investigation of the geomechanical problems. Comparison of the calculation results with the real deformation behaviour permits the validation of the numerical simulations and the reliability and limits of such analyses.
Petrogenesis and tectonic setting of the Middle Devonian Beitashan Formation volcanic rocks in the northern East Junggar, NW China: Insights from geochemistry, zircon U–Pb dating, and Hf isotopes
Authors: Xu Qian , Li Yongjun , Yang Gaoxue , Ning Wentao , Tong Lili , Duan Fenghao , Wu Le , Ren Pengfei
Published: December 2019

The Devonian volcanic rocks are widely distributed in the East Junggar (Xinjiang, NW China), preserving important magmatic records for investigating Palaeozoic tectonic evolution. The Beitashan Formation is mainly composed of pyroclastic rocks and sedimentary rocks in the lower section and intermediate–basic volcanic lava and pyroclastic rocks in the upper section. In this paper, we present geochronological, geochemical, and in situ Lu–Hf isotopic data for Beitashan Formation volcanic rocks from the East Junggar. Zircon U–Pb analyses from a basalt sample by laser ablation inductively coupled plasma mass spectrometry yielded a weighted mean age of 387.8 ± 4.5 Ma, indicating that it was generated in the Middle Devonian. The basic–intermediate volcanic rocks are tholeiitic to calc‐alkalic and are characterized by MgO (2.29–5.91 wt.%), low TiO2 (0.75–1.36 wt.%), and relatively high Al2O3 (15.82–16.73 wt.%). Furthermore, they display enrichment in light rare‐earth elements and large‐ion lithophile elements (such as Ba and Sr) and depletion in Nb, Ta, and Ti, along with slightly positive Eu anomalies (δEu = 0.83–1.15) and Ce anomalies (δCe = 1.00–1.11). In addition, in situ zircon Hf isotopic analyses from basalt samples show εHf(t) values ranging from +4.33 to +15.2, indicating a depleted mantle source with minor crustal contamination. They also show relatively low Nb/Zr (0.04–0.06), Th/Yb (0.67–3.83), and Ba/La (6.79–67.53) and high Ce/Th (7.71–18.94), Ba/Rb (21.39–294.28), and Ba/Th (31.42–486.58). The geochemical data suggest these rocks were likely derived from 10% to 30% partial melting of a garnet‐rich with minor spinel‐bearing Iherzolite depleted mantle metasomatized by slab‐derived fluids, with crustal contamination. Combined with the geological setting and previous studies, we suggest that the northern East Junggar was in a northward‐subducted island‐arc setting in the Devonian.
Depositional environmental controls on the genesis and characteristics of oil shale: Case study of the Middle Jurassic Shimengou Formation, northern Qaidam Basin, north‐west China
Authors: Wang Jun‐Xian , Sun Ping‐Chang , Liu Zhao‐Jun , Li Li
Published: December 2019

Two different types of oil shales (OSs) from the Middle Jurassic Shimengou Formation on the northern margin of the Qaidam Basin, north‐west China, provide a valuable opportunity to study the factors controlling the genesis of oil shales. This study presents the sedimentary characteristics of various types of oil shales from the Shimengou Formation and then discusses their possible genesis based on a comprehensive analysis on drillcores. The Shimengou Formation comprises a lower coal‐bearing member (J2sh1) and an upper shale member (J2sh2). The J2sh1 OS unit is composed of dark grey thin‐layered shales interbedded with coal seams, with total organic carbon (TOC) content of 18.8–34.1 wt.% (averagely 21.5 wt.%), and belonging to type II2 organic matter. The J2sh2 OS unit consists of dark grey to grey‐brown thick‐bedded shales and mudstone. The J2sh2 OS has a moderate abundance in organic matter, TOC contents of 6.3–11.5 wt.% (averagely 9.59 wt.%), and types I and II1 organic matters. During the deposition of the J2sh1 member, both braided river delta and freshwater–marsh facies dominate the succession, and OS developed in shallow lakes and swamps. Soon after, the depositional environment changed rapidly. Plentiful terrestrial and shallow water aquatic plants provided abundant organic matter for the sedimentation of OS and also promoted the formation of thinly‐bedded, high‐quality OS with type II2 organic matter. The frequent changes in depositional environments facilitated the formation of thin layers of oil shale. During the sedimentation of the J2sh2 member, in similar tectonic settings, the stable warm–humid climate makes the lake water deeper than before, and the oil shale was deposited mainly in a relatively deep lake. This led to a reduced supply of terrestrial organic matter, which came mainly from lake algae, leading to the formation of OS with a large, uniform thickness and the presence of types I and II2 organic matter.
Finite element method solution of mixed convection flow of Williamson nanofluid past a radially stretching sheet
Authors: Ibrahim Wubshet , Gamachu Dachasa
Published: December 2019

This computation reports the mixed convection flow of Williamson fluid past a radially stretching surface with nanoparticles under the effect of first‐order slip and convective boundary conditions. The coupled nonlinear ordinary differential equations (ODEs) are obtained from the partial differential equations, which are derived from the conservation of momentum, energy, and species. Then, utilizing suitable resemblance transformation, these ODEs were changed into dimensionless form and then solved numerically by means of a powerful numerical technique called the Galerkin finite element method. The effect of different parameters on velocity, temperature, and concentration profiles is inspected and thrashed out in depth by graphs and tables. The upshots exhibit that the velocity profile augments as the values of concentration buoyancy and mixed convection parameters are engorged. Also, the results demonstrated that both temperature and concentration profiles are improved with an enhancement in values of thermophoresis parameters. The outcomes also indicate that for finer values of magnetic field parameter and thermophoresis parameter, the numerical value of local Nusselt and Sherwood numbers is reduced.
Concentration versus streamflow trends of major ions and tritium in headwater streams as indicators of changing water stores
Authors: Cartwright Ian , Morgenstern Uwe , Hofmann Harald
Published: December 2019

Documenting the processes that control the variations in stream geochemistry at different streamflows is important for being able to use chemical tracers to understand catchment functioning. The concentrations of most solutes, including reactive cations (e.g., Na, Ca, K, and Mg) and anions that are primarily derived from precipitation (Cl and Br), in five headwater streams from southeast Australia vary little with streamflow and are close to being chemostatic. By contrast, NO3 and SO4 concentrations are higher at high streamflows. There is also a systematic increase of 3H activities from as low as 1.1 to as high as 2.6 TU with increasing streamflow. The changes in geochemistry cannot be explained solely by increased mineral dissolution at high streamflows or enhanced baseflow driven by hydraulic loading. They are best explained by an increased baseflow input augmented by water mobilized from shallower stores as the catchments wet up. The mean transit times of the water sustaining streamflow varies from 35 to 70 years at low streamflows to <7 years at high streamflows. The use of a range of geochemical tracers, including radioactive isotopes, allows the different possible causes of chemostatic behaviour to be assessed and improves our understanding of catchment functioning.
Components of obstetric violence in health facilities in Quito, Ecuador: A descriptive study on information, accompaniment, and position during childbirth
Authors: Meijer Magriet , Brandão Thais , Cañadas Sofía , Falcon Kirsten
Published: December 2019

Objective

To describe three factors of obstetric violence in health centers that attend births in Quito, Ecuador: information; accompaniment; and free position.

Method

A cross‐sectional descriptive study of 388 women was conducted, focusing on the analysis of three factors of obstetric violence. This study forms part of a larger study that explores the experiences of women in childbirth in Quito between July 1, 2016 and July 1, 2017.

Results

Of all procedures, the performance of episiotomies and the application of fundal pressure during the second stage of labor (Kristeller) stand out, as more than 35% of the women were not informed about them. In total, 121 (46.9%) women who gave birth vaginally were not given the opportunity to be accompanied by someone of their choice, neither in labor nor during delivery. While in the cases of cesarean deliveries, this increased to 116 (92.1%) women. A total of 119 (37.2%) women did not have the opportunity to choose their birthing position (or they did not know they could choose). During delivery, 138 (53.5%) women indicated the same.

Conclusion

Obstetric violence is seen in all three components: information; accompaniment; and free position.
Single‐walled carbon nanohorns modulate tenocyte cellular response and tendon biomechanics
Authors: Ekwueme Emmanuel C. , Rao Rohit , Mohiuddin Mahir , Pellegrini Michael , Lee Yong S. , Reiter Mary P. , Jackson James , Freeman Joseph W.
Published: December 2019

Subfailure ligament and tendon injury remain a significant burden to global healthcare. Here, we present the use of biocompatible single‐walled carbon nanohorns (CNH) as a potential treatment for the repair of sub‐failure injury in tendons. First, in vitro exposure of CNH to human tenocytes revealed no change in collagen deposition but a significant decrease in cell metabolic activity after 14 days. Additionally, gene expression studies revealed significant downregulation of collagen Types I and III mRNA at 7 days with some recovery after 14 days of exposure. Biomechanical tests with explanted porcine digitorum tendons showed the ability of CNH suspensions to modulate tendon biomechanics, most notably elastic moduli immediately after treatment. in vivo experiments demonstrated the ability of CNH to persist in the damaged matrix of stretch‐injured Sprague Dawley rat Achilles tendon but not significantly modify tendon biomechanics after 7 days of treatment. Although these results demonstrate the early feasibility of utility of CNH as a potential modality for tendon subfailure injury, additional work is needed to further validate and ensure clinical efficacy.
Co‐immobilization of cellulase and glucose oxidase on graphene oxide by covalent bonds: a biocatalytic system for one‐pot conversion of gluconic acid from carboxymethyl cellulose
Authors: Zhang Han , Hua Shao‐Feng , Zhang Lei
Published: December 2019

BACKGROUND

The objective of this research was to use a step‐by‐step method to prepare a novel biocatalytic system (GO‐CEL‐E/N‐GA‐GOD): ‐OH and ‐COOH on the surface of graphene oxide (GO) were used to immobilize cellulase (CEL) and glucose oxidase (GOD), respectively, which may be easier to control the loading of enzymes with different kinds, to achieve the one‐pot conversion of gluconic acid from carboxymethyl cellulose (CMC).

RESULTS

The loadings capability of CEL and GOD on GO‐CEL‐E/N‐GA‐GOD were 49.07 ± 7.47 mg g−1 and 10.22 ± 2.03 mg g−1, respectively. The multi‐enzyme systems had shallow temperature and pH optima of 40 °C and 5.0. The kinetic constants of GO‐CEL‐E/N‐GA‐GOD (of CEL‐GOD) were Km = 0.15 ± 0.02 (0.43 ± 0.09) mmol L−1, Vmax = 0.18 ± 0.01 (0.21 ± 0.07) μmol L−1 s−1, and kcat/Km = 24.12 ± 0.52 (17.74 ± 0.85) s−1 mmol−1 L. Nearly 65% of the initial activity of GO‐CEL‐E/N‐GA‐GOD could be retained after seven cycles. Notably the conversion of gluconic acid was able to reach 63.82 ± 8.03% within 2 h.

CONCLUSION

Step‐by‐step immobilization method made full use of different functional groups on GO, avoiding the competition for fixed sites between CEL and GOD in the immobilization processes. The results reflected the feasibility of the strategy to build bio‐microsystem as CEL and GOD immobilized on GO by covalent bonds to achieve the conversion from CMC to gluconic acid in one‐step. © 2019 Society of Chemical Industry
“Tau Protein Targeting Via Radioiodinated Azure A For Brain Theranostics: Radiolabeling, Molecular Docking, in vitro And in vivo Biological Evaluation”
Authors: Abdelaziz Gamal , Shamsel‐Din Hesham A. , Sarhan Mona O. , Gizawy Mohamed A.
Published: December 2019

Azure‐A is one of the phenothiazines (PTZs) derivatives which for decades have been used as antipsychotic drugs due to good lipophilic characteristics which enable them to pass through the blood brain barrier (BBB), besides the important property of enabeling investigation of the pathological forms of aggregated tau protein found in the neurons of the central nervous system. Radioiodination of Azure‐A was carried out via an electrophilic substitution reaction using chloramine‐T as oxidizing agent. The influence of various reaction parameters and conditions on radioiodination efficiency was investigated, and a high radiochemical yield of 92.07 ± 0.9 % was obtained. An in vitro cytotoxicity study of iodinated Azure‐A on three cell lines (HCT‐116, human colon carcinoma cell line; Hep‐G2, liver carcinoma cell line and HFB‐4, normal human melanocytes) was carried out, and the data revealed that ioiodinated Azure A has no to very low toxic effect. The in vivo biodistribution study of 131I‐Azure A showed a high brain uptake of 6.15 ± 0.09 % injected dose/g tissue organ at 30 minutes post‐injection, and its retention in brain remained high up to 2 hours, whereas the clearance from the body appeared to proceed via the renal system. The experimental data were confirmed by the molecular docking studies to predict the effect of radioiodination on the binding affinity of the parent molecule (Azure A) to tau paired helical filaments (PHFs). Both ligands showed better binding to S2 and S3 pockets of (PHFs). Consequently, radioiodinated Azure A seems to be a good candidate as an imaging agent for taupathies such as Alzheimer's disease, chronic traumatic encephalopathy, and corticobasal degeneration. Furthermore, it could be a very potent theranostics agent for brain tumors.
Early detection of lysosomal diseases by screening of cases of idiopathic splenomegaly and/or thrombocytopenia with a next‐generation sequencing gene panel
Authors: Muñoz Gloria , García‐Seisdedos David , Ciubotariu Crina , Piris‐Villaespesa Miguel , Gandía Marta , Martín‐Moro Fernando , Gutiérrez‐Solana Luis G. , Morado Marta , López‐Jiménez Javier , Sánchez‐Herranz Antonio , Villarrubia Jesús , del Castillo Francisco J.
Published: December 2019

Lysosomal diseases (LD) are a group of about 70 rare hereditary disorders (combined incidence 1:5000) in which diverse lysosomal functions are impaired, impacting multiple organs and systems. The first clinical signs and symptoms are usually unspecific and shared by hundreds of other disorders. Diagnosis of LD traditionally relies on performing specific enzymatic assays, if available, upon clinical suspicion of the disorder. However, the combination of the insidious onset of LD and the lack of awareness on these rare diseases among medical personnel results in undesirable diagnostic delays, with unchecked disease progression, appearance of complications and a worsened prognosis. We tested the usefulness of a next‐generation sequencing‐based gene panel for quick, early detection of LD among cases of idiopathic splenomegaly and/or thrombocytopenia, two of the earliest clinical signs observed in most LD. Our 73‐gene panel interrogated 28 genes for LD, 1 biomarker and 44 genes underlying non‐LD differential diagnoses. Among 38 unrelated patients, we elucidated eight cases (21%), five with LD (GM1 gangliosidosis, Sanfilippo disease A and B, Niemann‐Pick disease B, Gaucher disease) and three with non‐LD conditions. Interestingly, we identified three LD patients harboring pathogenic mutations in two LD genes each, which may result in unusual disease presentations and impact treatment. Turnaround time for panel screening and genetic validation was 1 month. Our results underline the usefulness of resequencing gene panels for quick and cost‐effective screening of LDs and disorders sharing with them early clinical signs.
Dengue proteins with their role in pathogenesis, and strategies for developing an effective anti‐dengue treatment: A review
Authors: Nasar Sitara , Rashid Naeem , Iftikhar Saima
Published: December 2019

Dengue virus is an arbovirus belonging to class Flaviviridae Its clinical manifestation ranges from asymptomatic to extreme conditions (dengue hemorrhagic fever/dengue shock syndrome). A lot of research has been done on this ailment, yet there is no effective treatment available for the disease. This review provides the systematic understanding of all dengue proteins, role of its structural proteins (C‐protein, E‐protein, prM) in virus entry, assembly, and secretion in host cell, and nonstructural proteins (NS1, NS2a, NS2b, NS3, NS4a, NS4b, and NS5) in viral assembly, replication, and immune evasion during dengue progression and pathogenesis. Furthermore, the review has highlighted the controversies related to the only commercially available dengue vaccine, that is, Dengvaxia, and the risk associated with it. Lastly, it provides an insight regarding various approaches for developing an effective anti‐dengue treatment.
Six‐month post‐surgical elevations in cartilage T1rho relaxation times are associated with functional performance 2 years after ACL reconstruction
Authors: Li Alan K. , Pedoia Valentina , Tanaka Matthew , Souza Richard B. , Ma C. Benjamin , Li Xiaojuan
Published: December 2019

The current study looks to: (i) investigate postural stability following anterior cruciate ligament (ACL) reconstruction, as assessed by Y‐Balance Test, by comparing single‐leg balance of the injured limb against those of controls and the uninjured limb; (ii) analyze the relationship between postural stability symmetry with localized cartilage matrix changes and the Knee Injury and Osteoarthritis Outcome Score (KOOS). Bilateral knee MRI of 36 patients who underwent ACL reconstruction were performed before surgery, 6 months, 1 year, and 2 years, postoperatively. Postural stability was evaluated based on Y‐Balance Test at 1 and 2 years. ACL patients were also split into three groups based on postural stability symmetry at 2 years and symmetry thresholds associated with elevated risks of lower extremity injury. Voxel‐based relaxometry employing analysis of covariance was used to analyze localized differences in cartilage composition at all time‐points (using quantitative magnetic resonance [MR] T1ρ and T2 mapping) between the three groups. The ACL patients displayed no significant deficits in postural stability. Compared with symmetric patients, those with asymmetric postural stability at 2 years had significantly prolonged cartilage T1ρ—indicating deterioration of the cartilage matrix—specifically in the injured knee's medial tibia as early as 6‐month post‐reconstruction. Prolonged T1ρ in asymmetric patients persisted up to 2 years, where the group also reported worse KOOS. Our results demonstrate an association between early stages of cartilage matrix deterioration and postural stability symmetry that may manifest in elevated lower extremity injury risk and worse patient‐reported outcomes. Quantitative MR, in combination with local analysis performed with voxel‐based relaxometry, is a tool to further study this relationship. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:1132‐1140, 2020
A sensitive electrochemical sensor modified with multi‐walled carbon nanotubes doped molecularly imprinted silica nanospheres for detecting chlorpyrifos
Authors: Huang Weihong , Zhou Xiaohua , Luan Yu , Cao Yunfei , Wang Ningwei , Lu Yi , Liu Tianshu , Xu Wanzhen
Published: December 2019

A highly sensitive and convenient electrochemical sensor, based on surface molecularly imprinted polymers and multiwalled carbon nanotubes, was successfully developed to detect chlorpyrifos in real samples. In order to solve the problems like uneven shapes, poor size accessibility, and low imprinting capacity, the layer of the molecularly imprinted polymer was prepared on the surface of silica nanospheres. Moreover, the doping of multiwalled carbon nanotubes greatly improved the electrical properties of developed sensor. Under the optimal conductions, the electrochemical response of the sensor is linearly proportional to the concentration of chlorpyrifos in the range of 5.0 × 10−12‐5.0 × 10−8 mol/L with a low detection limit of 8.1 × 10−13 mol/L. The prepared sensor exhibited multiple advantages such as low cost, simple preparation, convenient use, excellent selectivity, and good reproducibility. Finally, the prepared sensor was successfully used to detect chlorpyrifos in vegetable and fruit.
Why organizations join voluntary sustainable tourism associations: Implications for membership and sustainability monitoring systems
Authors: Peters Scott , Font Xavier , Bonilla‐Priego Maria Jesus
Published: December 2019

With the use of institutional theory, we study why organizations join a voluntary sustainable tourism association and how the organization–association dynamics change over time. We find a disconnection between the joining and monitoring motivations for the association and its members that leads to conflicting forces and confusion, resulting in goal misalignment and loss of monitoring data. Voluntary associations need to accommodate for organizations' need of social identity, the desire to learn from each other and the sense of belonging from membership (mimetic forces), with the desire to institutionalize the members to behave in increasingly standardized way (normative and eventually coercive forces).
Effect of germination and roasting on the proximate composition, total phenolics, and functional properties of black chickpea (Cicer arietinum)
Authors: Kumar Yogesh , Sharanagat Vijay Singh , Singh Lochan , Mani Saravanan
Published: December 2019

Germinated and microwave roasted black chickpea were evaluated for physical, proximate, pasting, functional, and antioxidant properties. A significant variation was observed in quality of grain upon germination and roasting. The effect of germination and roasting on functional groups was analyzed using Fourier‐transform infrared spectroscopy. The results showed that germination improved the physical and pasting properties, whereas roasting enhanced the functional properties. The lightness of germinated grains significantly improved as compared with dark colored roasted sample. The germinated sample was found rich in protein, whereas carbohydrates and fiber content increased in roasted sample. Water and oil absorption content were reduced by 7.14% and 5.13% in germination as compared with control. However, roasting significantly improved the water absorption capacity and oil absorption capacity by 69.51% and 6.41% as compared with control.
The North American Consortium for the Study of End‐Stage Liver Disease–Acute‐on‐Chronic Liver Failure Score Accurately Predicts Survival: An External Validation Using a National Cohort
Authors: Rosenblatt Russell , Shen Nicole , Tafesh Zaid , Cohen‐Mekelburg Shirley , Crawford Carl V. , Kumar Sonal , Lucero Catherine , Brown Robert S. , Jesudian Arun , Fortune Brett E.
Published: December 2019

Acute‐on‐chronic liver failure (ACLF) carries high short‐term mortality. The North American Consortium for the Study of End‐Stage Liver Disease (NACSELD)–ACLF score, positive if ≥2 organ failures are present, is a bedside tool that predicts short‐term mortality in patients with cirrhosis. However, it was created using major liver referral centers, where a minority of patients with cirrhosis are hospitalized. Therefore, this study used the Nationwide Inpatient Sample, a nationally representative database, from 2005 to 2014 to externally validate the NACSELD‐ACLF score in a cohort of patients with decompensated cirrhosis who were identified by a validated algorithm. Organ failures were identified using diagnosis codes. The primary objective was to evaluate the association between the NACSELD‐ACLF score and inpatient mortality, whereas secondary objectives compared outcomes depending on presence of infection or hospitalization at a transplant center. Multivariate logistic regression was used to compare outcomes, and area under the curve was calculated. There were 1,523,478 discharges that were included with 106,634 (7.0%) having a positive NACSELD‐ACLF score. Patients were a mean 58 years old, and a majority were white men. Infection was present in 33.7% of the sample. Inpatient survival decreased with each organ failure and if infection was present. Patients with the NACSELD‐ACLF score had significantly lower inpatient survival on crude (94% versus 48%; P < 0.001) and multivariate analysis (odds ratio [OR], 0.08; 95% confidence interval [CI], 0.07‐0.08) and area under the receiver operating characteristic curve 0.77 (95% CI, 0.77‐0.78). Liver transplant centers had clinically similar but significantly better survival at each organ failure, in patients with the NACSELD‐ACLF score, and on multivariate analysis (OR, 1.17; 95% CI, 1.13‐1.22). Using a national cohort, our study validated the NACSELD‐ACLF score as an excellent, simple bedside tool to predict short‐term survival in patients with decompensated cirrhosis.
Body Mass Index, Diabetes, and the Risk of Parkinson's Disease
Authors: Jeong Su‐Min , Han Kyungdo , Kim Dahye , Rhee Sang Youl , Jang Wooyoung , Shin Dong Wook
Published: December 2019

Background

There are conflicting findings in the literature regarding the association of body mass index and incidence of PD.

Objectives

This study aimed to investigate the association of body mass index with the risk of PD incidence while considering diabetes mellitus as a major confounding factor.

Methods

We examined 6,800,601 individuals (aged ≥40 years) who were free of PD using the database of the Korean National Health Insurance Service. Cox proportional hazard regression was used to assess adjusted hazard ratios for PD with adjustment for potential confounders. Stratified analyses by diabetes status were also performed.

Results

A total of 33,443 individuals were diagnosed with PD during the follow‐up period (7.3 years). An increased risk of PD incidence was observed in the underweight group versus the normal group (adjusted hazard ratio: 1.28; 95% confidence interval: 1.21–1.36), whereas a decreased risk of PD incidence was observed (adjusted hazard ratio: 0.88; 95% confidence interval: 0.88–0.93) in the obese group and (adjusted hazard ratio: 0.77; 95% confidence interval: 0.72–0.82) in the severely obese group. This association consistently persisted after stratification by diabetes mellitus status, with the steepest downward slope for PD risk present with increasing body mass index in patients with severe diabetes mellitus (i.e., long duration or complication).

Conclusions

Being underweight and diabetes mellitus were associated with an increased risk of PD incidence, and effect of being underweight was more prominent in those with diabetes mellitus, with a dose‐response relationship existing according to diabetes mellitus status. Further research is warranted to understand the clinical implications of the significant interaction between being underweight and diabetes mellitus status in the development of PD. © 2020 International Parkinson and Movement Disorder Society