bluuebunny/crossref_metadata_2025 huggingface dataset:
Design and Simulation of an Innovative Modular Four-Bar Linkage Robotic Arm: Analysis and Applications
Authors: Ma Jiajun , Luo Ziqi , Ding Chuan , Yuan Huimin
Published: September 2024

In response to the issues of traditional manipulators, such as difficulty in controlling the terminal posture during motion, low control precision, and complex structure, a modular mechanical arm based on a parallel four-bar terminal posture maintenance mechanism has been designed to meet the special requirements of terminal posture maintenance. By analyzing the motion mechanism of the manipulator, the shape space of the manipulator, the terminal position space, and the relationships of forward and inverse kinematics have been derived. A simulation model of the linkage manipulator was established in the Robotic Toolbook for Matlab environment, and structural simulation analysis and kinematic equation verification were conducted. The end positioning and attitude control of different manipulators are simulated by Matlab programming. The working space of the manipulators is calculated by Monte Carlo method, and compared with that of traditional planar manipulators. The results show the validity of the kinematics equation and the rationality of the end positioning control scheme of the linkage manipulator. Finally, the experiment verifies that the attitude retention rate of the modular decoupling manipulator is 97.78% under high load, which verifies the reliability of this scheme. In addition, the manipulator can simplify the complexity of the mechanical structure and complete the control requirements of the terminal attitude under the premise of increasing the working space as much as possible, which lays a foundation for the design and optimization of the manipulator in the field of modular terminal attitude.
Analysis of 4G/LTE Network Performance in North-Central Nigeria: A Comprehensive Drive Test Approach
Authors: Yusuf Samson Dauda , Isa Sule Idris , Kwaha Barnabas John
Published: September 2024

The proliferation of mobile devices and escalating demand for data services have resulted in a substantial increase in data traffic across Nigeria, especially in the North Central region due to heavy migration of individuals and organizations towards Abuja, the federal capital. However, despite the growing adoption of 4G/LTE networks in North Central Nigeria, users encounter persistent challenges in accessing high-speed internet and poor service network. This study investigates the performance of 4G/LTE networks in North-Central Nigeria using a comprehensive drive test methodology carried out in Abuja, Lafia and Makurdi. It covered a duration of 3hrs (12.00noon to 15.00pm) for 3days (3rd - 6th January, 2024). For each test day, drive tests covered a period of data measurements divided into 3,600 time-steps, with each time-step sized at 1sec; and scaled to 1:150 units. Key metrics including network speed, latency, uptime, coverage, and signal power were evaluated across major Mobile Network Operators. Result shows that D-NGN has the highest mean speed (9.543Mbps), packet loss (2.007%), uplink percentage (97.714%), and Network coverage (87.514%). It has the least latency (25.921) but high packet loss (2.007%). However, C-NGN shows lowest mean speed (6.638Mbps), uplink percentage (38.706%) and Signal power (-78.057dBm) but lowest mean packet loss (0.121%). A-NGN has the highest mean signal power (-61.867dBm) while B-NGN has highest latency (44.070ms) and lowest Network coverage (60.731%). This reveals that D-NGN has dominance in network performance, outperforming A-NGN, B-NGN, and C-NGN. It is recommended that MNOs in North-Central Nigeria should strategically enhance their network infrastructure to improve service delivery, particularly in suburban and rural areas where performance lags. D-NGN, the frontrunner in network speed and coverage, could further solidify its market leadership by addressing identified latency and packet loss issues especially in Makurdi. Moreover, MNOs with lower performance metrics could invest in expanding coverage and optimizing network configurations to meet user demands, thereby increasing competitiveness and customer satisfaction across the region.
WINNING MECHANISMS OF SURVIVAL: A CASE OF “BUL-ANON” RETAILERS IN RURAL PHILIPPINES
Authors: Bisnar Charlotte , Neoy Lisa , Villamor Mary Crist , Gil-Salapi Candy Elizabeth
Published: September 2024

This study focused on the challenges faced by a group of independent and small retailers called Bul-anon retailers and identified coping mechanisms adopted. The study was conducted to investigate the coping me­chanisms that can be utilized by other members of the retail industry to continue to thrive despite difficulties. Findings indicated that the challenges faced by the Bul-anon retailers revolved around three of the four primary business functions: marketing, finance/accounting, and operations. To avoid the significant impact of the above challenges, retailers adopted coping mechanisms to stay in business amidst large department stores and other businesses. How they handled their customers, being customer-oriented, was the winning mechanism for the survival of these retailers.
Finding forced trends in oceanic oxygen
Authors: Long Matthew C. , Deutsch Curtis , Ito Taka
Published: February 2016

Anthropogenically forced trends in oceanic dissolved oxygen are evaluated in Earth system models in the context of natural variability. A large ensemble of a single Earth system model is used to clearly identify the forced component of change in interior oxygen distributions and to evaluate the magnitude of this signal relative to noise generated by internal climate variability. The time of emergence of forced trends is quantified on the basis of anomalies in oxygen concentrations and trends. We find that the forced signal should already be evident in the southern Indian Ocean and parts of the eastern tropical Pacific and Atlantic basins; widespread detection of forced deoxygenation is possible by 2030–2040. In addition to considering spatially discrete metrics of detection, we evaluate the similarity of the spatial structures associated with natural variability and the forced trend. Outside of the subtropics, these patterns are not wholly distinct on the isopycnal surfaces considered, and therefore, this approach does not provide significantly advanced detection. Our results clearly demonstrate the strong impact of natural climate variability on interior oxygen distributions, providing an important context for interpreting observations.
Tectonic interpretation of the connectivity of a multiscale fracture system in limestone
Authors: Lei Qinghua , Wang Xiaoguang
Published: February 2016

This paper studies the statistics and tectonism of a multiscale natural fracture system in limestone. The fracture network exhibits a self‐similar characteristic with a correlation between its power law length exponent a and fractal dimension D, i.e., a ≈ D + 1. Contradicting the scale‐invariant connectivity of idealized self‐similar systems, the percolation state of trace patterns mapped at different scales and localities of the study area varies significantly, from well to poorly connected. A tectonic interpretation based on a polyphase fracture network evolution history is proposed to explain this discrepancy. We present data to suggest that the driving force for fracture formation may be dissipated at the end of a tectonic event when the system becomes connected. However, the “effective” connectivity can successively be reduced by cementation of early fractures and reestablished by subsequent cracking, rendering a variable “apparent” connectivity that can be significantly above the percolation threshold.
Magnetospheric ion influence on magnetic reconnection at the duskside magnetopause
Authors: Fuselier S. A. , Burch J. L. , Cassak P. A. , Goldstein J. , Gomez R. G. , Goodrich K. , Lewis W. S. , Malaspina D. , Mukherjee J. , Nakamura R. , Petrinec S. M. , Russell C. T. , Strangeway R. J. , Torbert R. B. , Trattner K. J. , Valek P.
Published: February 2016

Magnetospheric ions from the ring current, warm plasma cloak, and the plasmaspheric drainage plume all interact with the dusk flank magnetopause. During periods of strong magnetospheric convection, these ions may contribute significantly to the magnetospheric mass density at the magnetopause. Observations from the Magnetospheric Multiscale mission Hot Plasma Composition Analyzer at the duskside magnetopause near reconnection X lines show that ions from the ring current and warm plasma cloak may have high mass densities. However, these mass densities are not as large as the mass density in the magnetosheath. The results suggest that except for possible influence from the plasmaspheric drainage plume, the other major magnetospheric ion populations do not greatly influence asymmetric reconnection at the duskside magnetopause.
Disturbance zonal and vertical plasma drifts in the Peruvian sector during solar minimum phases
Authors: Santos A. M. , Abdu M. A. , Souza J. R. , Sobral J. H. A. , Batista I. S.
Published: February 2016

In the present work, we investigate the behavior of the equatorial F region zonal plasma drifts over the Peruvian region under magnetically disturbed conditions during two solar minimum epochs, one of them being the recent prolonged solar activity minimum. The study utilizes the vertical and zonal components of the plasma drifts measured by the Jicamarca (11.95°S; 76.87°W) incoherent scatter radar during two events that occurred on 10 April 1997 and 24 June 2008 and model calculation of the zonal drift in a realistic ionosphere simulated by the Sheffield University Plasmasphere‐Ionosphere Model‐INPE. Two main points are focused: (1) the connection between electric fields and plasma drifts under prompt penetration electric field during a disturbed periods and (2) anomalous behavior of daytime zonal drift in the absence of any magnetic storm. A perfect anticorrelation between vertical and zonal drifts was observed during the night and in the initial and growth phases of the magnetic storm. For the first time, based on a realistic low‐latitude ionosphere, we will show, on a detailed quantitative basis, that this anticorrelation is driven mainly by a vertical Hall electric field induced by the primary zonal electric field in the presence of an enhanced nighttime E region ionization. It is shown that an increase in the field line‐integrated Hall‐to‐Pedersen conductivity ratio
, which can arise from precipitation of energetic particles in the region of the South American Magnetic Anomaly, is capable of explaining the observed anticorrelation between the vertical and zonal plasma drifts. Evidence for the particle ionization is provided from the occurrence of anomalous sporadic E layers over the low‐latitude station, Cachoeira Paulista (22.67°S; 44.9°W)—Brazil. It will also be shown that the zonal plasma drift reversal to eastward in the afternoon two hours earlier than its reference quiet time pattern is possibly caused by weakening of the zonal wind system during the prolonged solar minimum period.
Data assimilation of surface displacements to improve geomechanical parameters of gas storage reservoirs
Authors: Zoccarato C. , Baù D. , Ferronato M. , Gambolati G. , Alzraiee A. , Teatini P.
Published: February 2016

Although the beginning of reservoir geomechanics dates back to the late 1960s, only recently stochastical geomechanical modelling has been introduced into the general framework of reservoir operational planning. In this study, the ensemble smoother (ES) algorithm, i.e., an ensemble‐based data assimilation method, is employed to reduce the uncertainty of the constitutive parameters characterizing the geomechanical model of an underground gas storage (UGS) field situated in the upper Adriatic sedimentary basin (Italy), the Lombardia UGS. The model is based on a nonlinear transversely isotropic stress‐strain constitutive law and is solved by 3‐D finite elements. The Lombardia UGS experiences seasonal pore pressure change caused by fluid extraction/injection leading to land settlement/upheaval. The available observations consist of vertical and horizontal time‐lapse displacements accurately measured by persistent scatterer interferometry (PSI) on RADARSAT scenes acquired between 2003 and 2008. The positive outcome of preliminary tests on simplified cases has supported the use of the ES to jointly assimilate vertical and horizontal displacements. The ES approach is shown to effectively reduce the spread of the uncertain parameters, i.e., the Poisson's ratio, the ratio between the horizontal and vertical Young and shear moduli, and the ratio between the virgin loading (I cycle) and unloading/reloading (II cycle) compressibility. The outcomes of the numerical simulations point out that the updated parameters depend on the assimilated measurement locations as well as the error associated to the PSI measurements. The parameter estimation may be improved by taking into account possible model and/or observation biases along with the use of an assimilation approach, e.g., the Iterative ensemble smoother, more appropriate for nonlinear problems.
The crust‐mantle interaction in continental subduction channels: Zircon evidence from orogenic peridotite in the Sulu orogen
Authors: Li Hai‐Yong , Chen Ren‐Xu , Zheng Yong‐Fei , Hu Zhaochu
Published: February 2016

A combined secondary ion mass spectrometer and laser ablation‐(multicollector)‐inductively coupled plasma mass spectrometer study of zircon U‐Pb ages, trace elements, and O and Hf isotopes was carried out for orogenic peridotite and its host gneiss in the Sulu orogen. Newly grown zircon domains exhibit weak zoning or no zoning, relatively low Th/U ratios (<0.1), low heavy rare earth element (HREE) contents, steep middle rare earth element‐HREE patterns, negative Eu anomalies, and negative to low δ18O values of −11.3 to 0.9‰ and U‐Pb ages of 220 ± 2 to 231 ± 4 Ma. Thus, these zircons would have grown from metasomatic fluids during the early exhumation of deeply subducted continental crust. The infiltration of metasomatic fluids into the peridotite is also indicated by the occurrence of hydrous minerals such as amphibole, serpentine, and chlorite. In contrast, relict zircon domains exhibit magmatic zircon characteristics. Their U‐Pb ages and trace element and Hf‐O isotope compositions are similar to those for protolith zircons from ultrahigh‐pressure metamorphic rocks in the Dabie‐Sulu orogenic belt. Thus, these relict magmatic zircons would be physically transported into the peridotite by metasomatic fluids originated from the deeply subducted continental crust. Therefore, the peridotite underwent metasomatism by aqueous solutions derived from dehydration of the deeply subducted continental crust during the early exhumation. It is these crustally derived fluids that would have brought not only such chemical components as Zr and Si but also tiny zircon grains from the deeply subducted crustal rocks into the peridotite at the slab‐mantle interface in continental subduction channels. As such, the orogenic peridotite records the crust‐mantle interaction at the deep continental subduction zone.
Influence of fortnightly tides on earthquake triggering at the East Pacific Rise at 9°50′N
Authors: Bhatnagar Tarini , Tolstoy Maya , Waldhauser Felix
Published: February 2016

The study of tidal forcing provides an opportunity to view the response of the solid Earth to known changes in stress. Earthquakes triggered by diurnal and semidiurnal tidal forces have been well documented for the deep ocean and some terrestrial environments. However, few studies examine the influence of fortnightly tides on earthquake triggering and only in terrestrial environments. We assess triggering of microearthquakes related to true fortnightly tides and fortnightly tidal modulations along the East Pacific Rise at 9°50′N, where strong diurnal and semidiurnal triggering of earthquakes has been observed. An ocean bottom seismograph experiment collected microearthquake data between October 2003 and January 2007, a time period that included a well‐documented submarine eruption culminating in January 2006. We examine how triggering changed through the build up to and aftermath of this seafloor‐spreading event. Results show that earthquakes occur preferentially during times of increasing peak volumetric stress leading up to the eruption, with strong statistical significance (Schuster Test p values up to 2.22e−31). However, the correlation loses its strength immediately prior to and during the eruptive period (p value as high as 0.2837), when competing tectonic and magmatic stresses may occur. Post‐eruption triggering reappears (p value 1.45e−26) but with opposite phase. Statistical significance is also explored using Monte Carlo method, highlighting limitations of swarm‐dominated time series for the Schuster Test. Nevertheless, the observations are consistent with a shift in the dominating stress triggering the earthquakes from extensional tectonics to magmatic processes, followed by a post‐eruption period of cooling, relaxation, and possibly magma chamber refilling.
Changing characteristics of extreme wet and dry spells of Indian monsoon rainfall
Authors: Vinnarasi R. , Dhanya C. T.
Published: February 2016

Modeling of extreme events and its dynamic behavior have always been an intriguing topic. Increase in the magnitude and frequency of extreme events has widely been reported in recent decades, which is attributed to abrupt changes in climate. Numerous studies on extreme Indian monsoon characteristics, using a coarse‐resolution data set, have pointed out significant changes in heavy precipitation pattern over India. However, these studies differ in their conclusions, emphasizing the need for a fine‐resolution analysis. The present study aims to analyze the spatiotemporal variations and trends in the extreme (wet and dry) Indian monsoon precipitation, using 0.25° × 0.25° high‐resolution gridded data for a period of 113 years (1901–2013). Significant increase in the maximum intensity of rainfall and spatial heterogeneity is observed over the past half century. In addition, significant negative trends in wet spell durations and positive trends in dry spell durations are observed over wet regions; whereas contrasting trends are observed over dry regions. A shift in the frequency distribution of extreme events during the monsoon period is also noticed. The 50 year return level of maximum intensity clearly shows positive trends over the past century. Though characteristics of extremes are observed to be highly localized, apparent signs of wet regions turning drier and dry regions turning wetter are obtained. A comprehensive insight into different characteristics (intensity, spell, onset, and frequency) of Indian monsoon extremes is provided, which will help in effective water resources management and flood/drought hazard preparedness.
Radiative effects of global MODIS cloud regimes
Authors: Oreopoulos Lazaros , Cho Nayeong , Lee Dongmin , Kato Seiji
Published: February 2016

We update previously published Moderate Resolution Imaging Spectroradiometer (MODIS) global cloud regimes (CRs) using the latest MODIS cloud retrievals in the Collection 6 data set. We implement a slightly different derivation method, investigate the composition of the regimes, and then proceed to examine several aspects of CR radiative appearance with the aid of various radiative flux data sets. Our results clearly show that the CRs are radiatively distinct in terms of shortwave, longwave, and their combined (total) cloud radiative effect. We show that we can clearly distinguish regimes based on whether they radiatively cool or warm the atmosphere, and thanks to radiative heating profiles, to discern the vertical distribution of cooling and warming. Terra and Aqua comparisons provide information about the degree to which morning and afternoon occurrences of regimes affect the symmetry of CR radiative contribution. We examine how the radiative discrepancies among multiple irradiance data sets suffering from imperfect spatiotemporal matching depend on CR and whether they are therefore related to the complexity of cloud structure, its interpretation by different observational systems, and its subsequent representation in radiative transfer calculations.
Numerical modeling of subaqueous sand dune morphodynamics
Authors: Doré Arnaud , Bonneton Philippe , Marieu Vincent , Garlan Thierry
Published: February 2016

The morphodynamic evolution of subaqueous sand dunes is investigated, using a 2‐D Reynolds‐averaged Navier‐Stokes numerical model. A laboratory experiment where dunes are generated under stationary unidirectional flow conditions is used as a reference case. The model reproduces the evolution of the erodible bed until a state of equilibrium is reached. In particular, the simulation exhibits the different stages of the bed evolution, e.g., the incipient ripple generation, the nonlinear bed form growing phase, and the dune field equilibrium phase. The results show good agreement in terms of dune geometrical dimensions and time to equilibrium. After the emergence of the first ripple field, the bed growth is driven by cascading merging sequences between bed forms of different heights. A sequence extracted from the simulation shows how the downstream bed form is first eroded before merging with the upstream bed form. Superimposed bed forms emerge on the dune stoss sides during the simulation. An analysis of the results shows that they emerge downstream of a slight deflection on the dune profile. The deflection arises due to a modification of the sediment flux gradient consecutive to a reduction in the turbulence relaxation length while the upstream bed form height decreases. As they migrate, superimposed bed forms grow on the dune stoss side and eventually provoke the degeneration of the dune crest. Cascading merging sequences and superimposed bed forms dynamics both influence the dune field evolution and size and therefore play a fundamental role in the dune field self‐organization process.
The chronology and tectonic style of landscape evolution along the elevated Atlantic continental margin of South Africa resolved by joint apatite fission track and (U‐Th‐Sm)/He thermochronology
Authors: Wildman Mark , Brown Roderick , Beucher Romain , Persano Cristina , Stuart Fin , Gallagher Kerry , Schwanethal James , Carter Andrew
Published: February 2016

Atlantic‐type continental margins have long been considered “passive” tectonic settings throughout the entire postrift phase. Recent studies question the long‐term stability of these margins and have shown that postrift uplift and reactivation of preexisting structures may be a common feature of a continental margin's evolution. The Namaqualand sector of the western continental margin of South Africa is characterized by a ubiquitously faulted basement but lacks preservation of younger geological strata to constrain postrift tectonic fault activity. Here we present the first systematic study using joint apatite fission track and apatite (U‐Th‐Sm)/He thermochronology to achieve a better understanding on the chronology and tectonic style of landscape evolution across this region. Apatite fission track ages range from 58.3 ± 2.6 to 132.2 ± 3.6 Ma, with mean track lengths between 10.9 ± 0.19 and 14.35 ± 0.22 µm, and mean (U‐Th‐Sm)/He sample ages range from 55.8 ± 31.3 to 120.6 ± 31.4 Ma. Joint inverse modeling of these data reveals two distinct episodes of cooling at approximately 150–130 Ma and 110–90 Ma with limited cooling during the Cenozoic. Estimates of denudation based on these thermal histories predict approximately 1–3 km of denudation coinciding with two major tectonic events. The first event, during the Early Cretaceous, was driven by continental rifting and the development and removal of synrift topography. The second event, during the Late Cretaceous, includes localized reactivation of basement structures as well as regional mantle‐driven uplift. Relative tectonic stability prevailed during the Cenozoic, and regional denudation over this time is constrained to be less than 1 km.
From ocean depths to mountain tops: Uplift of the Troodos ophiolite (Cyprus) constrained by low‐temperature thermochronology and geomorphic analysis
Authors: Morag Navot , Haviv Itai , Katzir Yaron
Published: February 2016

The timing and mode of uplift of the Troodos ophiolite are constrained by low‐temperature thermochronology combined with geomorphic analysis. Zircon (U‐Th)/He and apatite fission track cooling ages in the Troodos plutonic sequence are all Cretaceous (83–106 Ma) and within error of published zircon U‐Pb crystallization ages. This indicates early cooling of the oceanic crust and termination of spreading axis magmatism at ~90 Ma. Apatite (U‐Th)/He ages decrease with reconstructed crustal depths from ~40 Ma near the top of the sheeted‐dike complex to ~4 Ma within the mantle sequence. A prominent inflection point in the age versus depth curve defines the bottom of the exhumed helium partial retention zone and records the onset of rapid exhumation of the main Troodos massif at 6 ± 2 Ma. Inverse thermal modeling supports this conclusion, indicating that the timing of uplift is earlier than previously estimated. The boundaries of the mantle sequence exposed in the core of the Troodos structure closely overlap the boundaries of a concentric zone delineated by high local relief and higher channel steepness indices, indicating differential exhumation and uplift of this area relative to its surroundings. This zone also overlaps with a prominent negative Bouguer gravity anomaly. The timing and pattern of the Troodos ophiolite uplift suggest that it is driven by serpentinite diapirism, possibly triggered by Miocene reactivation of subduction along the Cyprean Arc. The worldwide ubiquity of suprasubduction zone ophiolites may thus reflect the importance of extensive serpentinization at the overthrusting mantle wedge in obduction processes.
Characterization of reciprocity gaps from interference tests in fractured media through a dual porosity model
Authors: Sanchez‐Vila X. , Ackerer P. , Delay F. , Guadagnini A.
Published: February 2016

We analyze drawdown reciprocity gaps emerging in interference tests performed in a confined fissured karstic formation. Modeling the system as a dual porosity continuum allows characterizing the dynamics of the relative contribution of the connected fractures and the rock matrix to the total flow rate extracted at the pumping wells. Observed lack of reciprocity of drawdowns can then be linked to the occurrence of processes that are not accounted for in the classical flow models based on a single‐continuum representation of the system through flow equations grounded on Darcy's law only. We show that interpreting the system as a dual porosity continuum can cause drawdown reciprocity gaps to emerge as a consequence of local effects associated with an identifiable contribution of the matrix to the total fluid extracted at the well location during pumping. These theoretical results are then employed to identify the contribution to the flow being supplied to the pumping well by the low conductivity matrix constituting the host rock formation, in contrast to that provided by the fractures. An application to data from two interference tests performed at the Hydrogeological Experimental Site (HES) in Poitiers, France, illustrates the approach. We show that, whenever the matrix is assumed to provide a contribution to the total flow rate extracted, nonreciprocity is expected, the latter being linked to the occurrence of a differential drawdown between fracture and matrix at the pumping well. This difference decreases with time in the example presented, displaying a power law late time behavior, with nonreciprocity effects persisting up to remarkably long times.
Future changes to the Indonesian Throughflow and Pacific circulation: The differing role of wind and deep circulation changes
Authors: Sen Gupta Alex , McGregor Shayne , van Sebille Erik , Ganachaud Alexandre , Brown Jaclyn N. , Santoso Agus
Published: February 2016

Climate models consistently project a substantial decrease in the Indonesian Throughflow (ITF) in response to enhanced greenhouse warming. On interannual timescales ITF changes are largely related to tropical Pacific wind variability. However, on the multidecadal timescales investigated here we demonstrate that regional winds and associated changes in the upper ocean circulation cannot explain the projected ITF decrease. Instead, the decrease is related to a weakening in the northward flow of deep waters entering the Pacific basin at ~40°S and an associated reduction in the net basin‐wide upwelling to the north of the southern tip of Australia. This can be traced back to consistent changes in the Antarctic Circumpolar Current and Southern Ocean overturning, although questions still remain as to the ultimate drivers. In contrast to the ITF decrease, substantial projected changes to the upper ocean circulation of the Pacific basin are well explained by robust changes in the surface winds.
Does Renin‐Angiotensin System Blockade Protect Lupus Nephritis Patients From Atherosclerotic Cardiovascular Events? A Case–Control Study
Authors: Tselios Konstantinos , Gladman Dafna D. , Su Jiandong , Urowitz Murray B.
Published: February 2016

Objective

Angiotensin‐converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) are used as an adjuvant treatment in lupus nephritis (LN) patients with proteinuria. The primary aim of this study was to discover whether ACE inhibitors/ARBs have an atheroprotective effect similar to other, at‐risk, populations.

Methods

A total of 144 patients (cases; mean ± SD age at onset 34 ± 12.1 years, followup 14.9 ± 8.6 years) with LN who were treated with ACE inhibitors/ARBs for at least 5 years were enrolled. The control group comprised 301 LN patients (mean ± SD age at onset 34.1 ± 13.2 years, followup 13.4 ± 7.9 years) with no such treatment. All patients were followed for the occurrence of atherosclerotic cardiovascular events (CVEs), consisting of transient ischemic attack and stroke, angina, myocardial infarction, percutaneous transluminal coronary angioplasty (PTCA), coronary artery bypass graft (CABG), and congestive heart failure. Patients with preexisting CVEs were excluded.

Results

There were no significant differences in the cumulative occurrence of CVEs (9.7% for treated versus 8.6% for nontreated patients; P = 0.708); however, hard events (stroke, myocardial infarction, CABG, and PTCA) were less frequent in treated patients (4.17% versus 5.32%). Cases were more frequently hypertensive (100% versus 52.8%; P < 0.001) and diabetic (10.4% versus 4.7%; P = 0.021), whereas controls more frequently had hypercholesterolemia (27.9% versus 18.1%; P = 0.024) and elevated triglycerides (14% versus 4.9%; P = 0.004); other variables did not differ significantly. Regression analysis failed to confirm ACE inhibitor/ARB nonuse as an important predictor of future CVEs.

Conclusion

Our data do not support the hypothesis that ACE inhibitors/ARBs may be protective against atherosclerotic CVEs in LN patients.
Novel Hybrid Yarn Textile Thermoplastic Composites for Function‐Integrating Multi‐Material Lightweight Design
Authors: Modler Niels , Hufenbach Werner , Cherif Chokri , Ulbricht Volker , Gude Maik , Maron Bernhard , Weck Daniel , Filippatos Angelos , Wiemer Hajo , Langkamp Albert
Published: February 2016

Future mobility applications are characterized by a high level of resource efficiency due to the application of novel lightweight materials and function‐integrating, multi‐material design concepts. Textile thermoplastic composites in particular pave the way for lightweight components characterized by highly specific mechanical properties and efficient production processes. This essay presents the strategy pursued by the Collaborative Research Centre SFB 639 “Textile‐reinforced composite components for function‐integrating multi‐material design in complex lightweight applications”, a concept for the holistic analysis of complex process chains for hybrid yarn textile thermoplastic (HYTT) composites and the idea behind the innovative FiF electric mobility technology demonstrator vehicle.
Antiphotobleaching: A Type of Structurally Rigid Chromophore Ready for Constructing Highly Luminescent and Highly Photostable Europium Complexes
Authors: Wei Huibo , Zhao Zifeng , Wei Chen , Yu Gang , Liu Zhiwei , Zhang Bin , Bian Jiang , Bian Zuqiang , Huang Chunhui
Published: February 2016

Antiphotobleaching is a critical challenge in the field of luminescent lanthanide complexes (LLCs) as well as in many disciplines concerning organic luminescent processes. In this work, a type of structurally rigid organic ligand, 4‐hydroxy‐1,5‐naphthyridine (ND), is developed, which can not only efficiently sensitize the europium emission but also demonstrate unique photostability. A series of ND derivatives with different substituent groups are synthesized and their singlet and triplet excited state energy levels are systematically investigated. Photophysical characterizations of the corresponding europium complexes reveal that the sensitization efficiencies (ηsens) are close to 100% and the total photoluminescence quantum yields can reach up to 84%. Most importantly, these structurally rigid luminescent europium complexes exhibit outstanding photostability and thermostability. Unlike the widely used β‐diketone complexes that are easily photodegraded, ND‐based chelates show no obvious degradation during the UV aging test (10 W m−2 340 nm Ultraviolet A irradiation) within 200 h. Such superior UV resistance is even better than that of the famous compound tris(8‐hydroxyquinolate)aluminum (Alq3). Possible reasons are discussed and a general rule for designing photostable LLCs is proposed. Such a chromophore is very promising for introducing luminescent materials with good photostability in potential application in many disciplines.
Au‐NP‐Decorated Crystalline FeOCl Nanosheet: Facile Synthesis by Laser Ablation in Liquid and its Exclusive Gas Sensing Response to HCl at Room Temperature
Authors: Wang Yingying , Zhang Hongwen , Zhu Yudong , Dai Zhengfei , Bao Haoming , Wei Yi , Cai Weiping
Published: February 2016

Here an alternative preparation route, pulsed laser ablation in liquid (LAL) of FeCl3solution, is reported to facilely synthesize crystalline iron oxychloride (FeOCl) nanosheets at ambient conditions. Well‐dispersed spherical gold (Au) nanoparticles (NPs) are simultaneously decorated on surface of the FeOCl nanosheets, which possess (010) preferred orientations with microsized dimensions in planar and tens of nanometers in thickness. The crystalline size and composition of the Au/FeOCl can be effectively modulated by simply changing FeCl3concentrations. Technical observations illustrate that the nanocomposites possess good thermal stability and surface of which adsorbs abundant H2O molecularly and oxygen species chemically. The FeOCl nanosheets are formed through chemical side hydrolysis reaction in the localized liquid region with gradient temperature, which is derived from thermal transfer of LAL‐induced plasma plume. The Au/FeOCl nanocomposites, as chemiresistors, show exceptionally high sensing response and perfect selectivity to HCl gas at room temperature. The excellent sensing behavior is ascribed to the Au‐NP‐enhanced surface chemisorption of oxygen species and selective adsorption of HCl for FeOCl nanosheets. The synthesized Au/FeOCl nanocomposites provide a new candidate for exclusive HCl detection. And the proposed LAL‐assisted fabrication routes might open new perspectives for formation of other metal oxychloride compounds.
Nickel‐Catalyzed α‐Benzylation of Arylacetonitriles via CO Activation
Authors: Xiao Jing , Yang Jia , Chen Tieqiao , Han Li‐Biao
Published: February 2016

Efficient Ni‐catalyzed direct cross‐couplings of benzylic alcohol derivatives with arylacetonitriles via CO activation are described. Various α‐benzylated arylacetonitriles including those with functional groups can be prepared under mild reaction conditions.

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Facile Synthesis and Isolation of Secondary Amines via a Sequential Titanium(IV)‐Catalyzed Hydroamination and Palladium‐Catalyzed Hydrogenation
Authors: Lui Erica K. J. , Schafer Laurel L.
Published: February 2016

An atom economical and catalytic route for the synthesis of aryl‐ and alkyl‐substituted secondary amines has been developed. Using a bis(amidate)bis(amido)titanium(IV) precatalyst, the hydroamination of terminal alkynes with a range of amines results in the selective formation of the anti‐Markovnikov product. The crude enamine/imine mixtures are effectively hydrogenated using palladium on carbon (Pd/C) and H2 to afford the corresponding secondary amine in excellent yields. Simple work‐up procedures allow for the isolation of pure compounds while avoiding purification via column chromatography.

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Organophotocatalytic Synthesis of Phosphoramidates
Authors: Meazza Marta , Kowalczuk Agnieszka , Shirley Luke , Yang Jung Woon , Guo Hao , Rios Ramon
Published: February 2016

We describe the use of visible light in conjunction with an organic dye for the synthesis of phosphoramidates. Cross dehydrogenative coupling reactions between phosphites and amines are reported using organic dyes and light as catalysts for the first time. It is not only a novel application of organic dyes but also fulfils the requirement of sustainability and green chemistry avoiding the use of chromatographic purification techniques. The product was simply isolated from the reaction mixture via an acid‐base work‐up procedure, rendering the pure product in good yields.

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The Lateral Cross‐Linking of Polyurethane Using Grafted Epichlorohydrin and the Impact on the Tensile and Thermal Properties
Authors: Chung Yong‐Chan , Lee Byung Hee , Choi Jae Won , Chun Byoung Chul
Published: February 2016

Epichlorohydrin (ECH) was used as a cross‐linking agent for a series of polyurethanes (PU series). The spectroscopic, thermal, tensile, shape memory, low‐temperature flexibility, and water vapor permeability properties of these PUs were compared with those of a control polyurethane series (CPU series) without ECH cross‐linking. In the thermal test, the soft segment crystallization of the PU series disappeared as the ECH cross‐linking increased. The glass transition temperature (Tg) of the PU and CPU series slightly increased with the increase in ECH content. The tensile strength of the PU series sharply increased at a critical ECH content, whereas that of the CPU series did not. The breaking strain of the PU and CPU series remained the same with the increase in ECH content. The shape recovery of the PU series remained above 90% at 45°C but increased moderately with the increase in ECH content at 0°C. Finally, the PU series with ECH cross‐linking demonstrated better low‐temperature flexibility and lower water vapor permeability than the unmodified PU.
Rhodium‐Catalyzed Enantioselective Arylation of N‐Substituted α,β‐Unsaturated γ‐Lactams: Preparation of Chiral 4‐Aryl‐2‐Pyrrolidones
Authors: Fang Jo‐Hsuan , Chang Chiung‐An , Gopula Balraj , Kuo Ting‐Shen , Wu Ping‐Yu , Henschke Julian P. , Wu Hsyueh‐Liang
Published: February 2016

The preparation of chiral 4‐aryl‐2‐pyrrolidones by conjugate addition catalyzed by a rhodium(I) complex, comprising the chiral bicyclo[2.2.1] diene ligand 1 e, is reported. The reaction of various arylboronic acids and α,β‐unsaturated γ‐lactams 2 bearing various N‐substituents proceeds in a highly stereoselective fashion (93–99.5 % ee) even in the presence of only 0.5 mol % of the Rh catalyst affording the corresponding addition products in 31–99 % yield.
Nonlinear selective reflection spectroscopy of V‐type atomic system at the gas‐solid interface
Authors: Meng Tengfei , Ji Zhonghua , Su Dianqiang , Zhao Yanting , Xiao Liantuan , Jia Suotang
Published: February 2016

We theoretically present the nonlinear selective reflection spectroscopy of V‐type atomic system at gas‐solid interface in a pump‐probe scheme. The saturation and coherence effects are distinguished by solving Liouville equation in the absence and presence of reduced density matrix element between the two excited levels. When the coherence effect exists, two peaks appear in reflection spectroscopy with asymmetry lineshape. We investigate the dependence of reflection spectroscopy on pump field intensity, frequency detuning and coherent decay rate induced by collision between atoms. The lineshape can be explained based on reflection spectroscopy contributed from atoms with negative (before collision) and positive (after collision) velocities, single‐photon and two‐photon processes. This study is helpful for investigating quantum coherence and dynamic processes of atoms at gas‐solid interface.
AN ODORANT‐BINDING PROTEIN INVOLVED IN PERCEPTION OF HOST PLANT ODORANTS IN LOCUST Locusta migratoria
Authors: Li Jia , Zhang Long , Wang Xiaoqi
Published: February 2016

Locusts, Locusta migratoria (Orthoptera: Acrididae), are extremely destructive agricultural pests, but very little is known of their molecular aspects of perception to host plant odorants including related odorant‐binding proteins (OBPs), though several OBPs have been identified in locust. To elucidate the function of LmigOBP1, the first OBP identified from locust, RNA interference was employed in this study to silence LmigOBP1, which was achieved by injection of dsRNA targeting LmigOBP1 into the hemolymph of male nymphs. Compared with LmigOBP1 normal nymphs, LmigOBP1 knockdown nymphs significantly decreased food (maize leaf, Zea mays) consumption and electro‐antennography responses to five maize leaf volatiles, ((Z)‐3‐hexenol, linalool, nonanal, decanal, and (Z)‐3‐hexenyl acetate). These suggest that LmigOBP1 is involved in perception of host plant odorants.
Ocular Fluid Analysis in Children Reveals Interleukin‐29/Interferon‐λ1 as a Biomarker for Juvenile Idiopathic Arthritis–Associated Uveitis
Authors: Haasnoot Anne‐Mieke J. W. , Kuiper Jonas J. W. , Hiddingh Sanne , Schellekens Peter A. W. J. F. , de Jager Wilco , Imhof Saskia M. , Radstake Timothy R. D. J. , de Boer Joke H.
Published: February 2016

Objective

Childhood uveitis is a vision‐threatening inflammatory eye disease commonly attributed to juvenile idiopathic arthritis (JIA). The pathogenesis is poorly understood, which makes clinical management challenging. We analyzed soluble mediators in ocular fluid (aqueous humor [AqH]) and serum from children with JIA‐associated uveitis and common childhood uveitis to identify potential biomarkers and investigate the ocular microenvironment of this sight‐threatening eye disease.

Methods

AqH (n = 73) and paired serum (n = 66) samples were analyzed for 51 soluble mediators of inflammation by multiplex immunoassay. Twenty‐one children with JIA‐associated uveitis were compared to 15 children with chronic anterior uveitis without arthritis, 29 children with noninfectious idiopathic uveitis, and 8 children with noninflammatory conditions (controls). For visualization of the joint effect of multiple mediators, we used the radial coordinate visualization (Radviz) method. Optimal biomarker level cutoffs were also determined.

Results

The levels of interleukin‐29 (IL‐29)/interferon‐λ1 (IFNλ1) were decreased (P < 0.001) and the levels of latency‐associated peptide and osteoprotegerin were increased (P = 0.002 andP = 0.001, respectively) in samples of AqH, but not serum, from patients with JIA‐associated uveitis. Multivariate analysis correcting for disease activity and treatment revealed that intraocular levels of IL‐29/IFNλ1 were specifically decreased in patients with JIA‐associated uveitis as compared to those with idiopathic uveitis. Indeed, JIA‐associated uveitis patients and idiopathic uveitis patients showed distinct profiles of intraocular soluble mediators. IL‐29/IFNλ1 showed a high area under the curve value (0.954), with 23.5 pg/ml as the optimal cutoff value.

Conclusion

We identified IL‐29/IFNλ1 as an intraocular biomarker for JIA‐associated uveitis, which suggests that aberrant IFNλ signaling might be important in JIA‐associated uveitis and distinct from other forms of childhood uveitis.
Development of Biomarker Models to Predict Outcomes in Lupus Nephritis
Authors: Wolf Bethany J. , Spainhour John C. , Arthur John M. , Janech Michael G. , Petri Michelle , Oates Jim C.
Published: February 2016

Objective

The American College of Rheumatology guidelines for the treatment of lupus nephritis recommend change in induction therapy when response to therapy has not occurred within 6 months. Response is not defined, and renal fibrosis can occur while waiting for this end point. Therefore, a decision support tool to better define response is needed to guide clinicians when starting patients on therapy. This study was undertaken to identify biomarker models with sufficient predictive power to develop such a tool.

Methods

Urine samples from 140 patients with biopsy‐proven lupus nephritis who had not yet started induction therapy were analyzed for a panel of urinary biomarkers. Univariate receiver operating characteristic (ROC) curves were generated for each individual biomarker and compared to the ROC area under the curve values from machine learning models developed using random forest algorithms. Biomarker models of outcome developed with novel markers in addition to clinical markers were compared to those developed with traditional clinical markers alone.

Results

Models developed with the combined traditional and novel biomarker panels demonstrated clinically meaningful predictive power. Markers most predictive of response were chemokines, cytokines, and markers of cellular damage.

Conclusion

This is the first study to demonstrate the power of low‐abundance biomarker panels and machine learning algorithms for predicting lupus nephritis outcomes. This is a critical first step in research to develop clinically meaningful decision support tools.
Endurance Exercise Improves Molecular Pathways of Aerobic Metabolism in Patients With Myositis
Authors: Munters Li Alemo , Loell Ingela , Ossipova Elena , Raouf Joan , Dastmalchi Maryam , Lindroos Eva , Chen Yi‐Wen , Esbjörnsson Mona , Korotkova Marina , Alexanderson Helene , Nagaraju Kanneboyina , Crofford Leslie J. , Jakobsson Per‐Johan , Lundberg Ingrid E.
Published: February 2016

Objective

Endurance exercise demonstrates beneficial effects in polymyositis/dermatomyositis (PM/DM); however, the molecular effects of exercise on skeletal muscle are incompletely understood. We undertook this controlled pilot study to investigate the effects of a 12‐week endurance exercise training program on the molecular profile of skeletal muscle in patients with established PM/DM compared to a nonexercised control group of patients with established PM/DM.

Methods

Fifteen patients (7 in the exercise group and 8 in the control group) with paired baseline and 12‐week follow‐up muscle biopsy samples were included. Messenger RNA expression profiling, mass spectrometry–based quantitative proteomics, and immunohistochemical analyses were performed on muscle biopsy samples to determine molecular adaptations associated with changes in clinical measurements induced by endurance exercise.

Results

Compared to the control group, the exercise group improved in minutes of cycling time (P < 0.01) and Vo2 max (P < 0.05). The exercise group also had reduced disease activity (P < 0.05) and reduced lactate levels at exhaustion (P < 0.05). Genes related to capillary growth, mitochondrial biogenesis, protein synthesis, cytoskeletal remodeling, and muscle hypertrophy were up‐regulated in the exercise group, while genes related to inflammation/immune response and endoplasmic reticulum stress were down‐regulated. Mitochondrial pathways including the oxidative phosphorylation metabolic pathway were most affected by the endurance exercise, as demonstrated by proteomics analysis. The exercise group also showed a higher number of capillaries per mm2 in follow‐up biopsy samples (P < 0.05).

Conclusion

Our data indicate that endurance exercise in patients with established PM and DM may activate an aerobic phenotype and promote muscle growth and simultaneously suppress the inflammatory response in these patients’ muscles, as supported by a combination of data on gene expression, proteomics, and capillary density in repeated muscle biopsies.