bluuebunny/crossref_metadata_2025 huggingface dataset:
Modeling dust emission response to MIS 3 millennial climate variations from the perspective of East European loess deposits
Authors: Sima A. , Kageyama M. , Rousseau D.-D. , Ramstein G. , Balkanski Y. , Antoine P. , Hatté C.
Published: January 2013

Abstract. European loess sequences of the last glacial period (~ 100–15 kyr BP) show periods of strong dust accumulation alternating with episodes of reduced sedimentation, favoring soil development. In the western part of the loess belt centered around 50° N, these variations appear to have been caused by the North Atlantic rapid climate changes: the Dansgaard-Oeschger (DO) and Heinrich (H) events. It has been recently suggested that the North-Atlantic climate signal can be detected further east, in loess deposits from Stayky (50° 05.65' N, 30° 53.92' E), Ukraine. Here we use climate and dust emission modeling to investigate this data interpretation. We focus on the areas north and northeast of the Carpathians, where loess deposits can be found, and the corresponding main dust sources must have been located as well. The simulations, performed with the LMDZ atmospheric general circulation model and the ORCHIDEE land-surface model, represent a Greenland stadial, a DO interstadial and an H event respectively. Placed in Marine Isotope Stage 3 (~ 60–25 kyr BP) conditions, they only differ by the surface conditions imposed in the North Atlantic between 30° and 63° N. The main source for the loess deposits in the studied area is identified as a dust deflation band, with two very active spots located west–northwest from our reference site. Emissions only occur between February and June. Differences from one deflation spot to another, and from one climate state to another, are explained by analyzing the relevant meteorological and surface variables. Over most of the source region, the annual emission fluxes in the "interstadial" experiment are 30 to 50% lower than the "stadial" values; they would only be about 20% lower if the inhibition of dust uplift by the vegetation were not taken into account. Assuming that lower emissions result in reduced dust deposition leads us to the conclusion that the loess-paleosol stratigraphic succession in the Stayky area reflects indeed North-Atlantic millennial variations. In the main deflation areas of Western Europe, the vegetation effect alone determined most of the ~ 50% stadial-interstadial flux differences. Even if its impact in Eastern Europe is less pronounced, this effect remains a key factor in modulating aeolian emissions at millennial timescale. Conditions favorable to initiating particularly strong dust storms within a few hundred kilometers upwind from our reference site, simulated in the month of April of the "H event" experiment, support the identification of H events as layers of particularly coarse sedimentation in some very detailed profiles.
Evidence of non-Darcy flow and non-Fickian transport in fractured media at laboratory scale
Authors: Cherubini C. , Giasi C. I. , Pastore N.
Published: January 2013

Abstract. Accurate predictions of solute propagation in fractured rocks are of particular importance when assessing exposure pathways through which contaminants reach receptors during a risk assessment procedure, as well as when dealing with cleanup and monitoring strategies. The difficulty in modeling fractured media leads to the application of simplified analytical solutions that fail to reproduce flow and transport patterns in such complex geological formations. A way for understanding and quantifying the migration of contaminants in groundwater systems is that of analyzing tracer transport. Experimental data obtained under controlled conditions such as in a laboratory allow to increase the understanding of the fundamental physics of fluid flow and solute transport in fractures. In this study laboratory hydraulic and tracer tests have been carried out on an artificially created fractured rock sample. The tests regard the analysis of the hydraulic loss and the measurement of breakthrough curves for saline tracer pulse inside a rock sample of parallelepiped (0.60 × 0.40 × 0.8 m) shape. The effect of the experimental apparatus on flow and transport tests has been estimated. In particular the convolution theory has been applied in order to remove the effect of acquisition apparatus on tracer experiment. The experimental results have shown evidence of a non-Darcy relationship between flow rate and hydraulic loss that is best described by Forchheimer's law. The observed experimental breakthrough curves of solute transport have been modeled by the classical one-dimensional analytical solution for advection–dispersion equation (ADE) and the single rate mobile–immobile model (MIM). The former model does not fit properly the first arrival and the tail while the latter provides a very decent fit.
Characterization of groundwater dynamics in landslides in varved clays
Authors: van der Spek J. E. , Bogaard T. A. , Bakker M.
Published: January 2013

Abstract. Groundwater dynamics may play a significant role in landslides. A detailed model is developed of the groundwater dynamics in landslides in varved clays in the Trièves area in the French Alps. The varved clays consist of a sequence of alternating silt and clay layers, covered by a colluvium layer and cut through by fissures. The hydraulic conductivity of the clay layers is negligible compared to the silt layers. It is conceptualized that fissures form a hydraulic connection between the colluvium and the varved clays. Groundwater recharge flows through the colluvium into the fissures where water is exchanged horizontally between the fissure and the silt layers of the varved clays. Groundwater flow in the colluvium is simulated with the Boussinesq equation while flow in the silt layers of the varved clays is simulated with the Richards' equation. Longitudinal outflow from the fissure is simulated with a linear-reservoir model. Scattered data of relatively short monitoring periods is available for several landslides in the region. A good similarity between observed and simulated heads is obtained, especially when considering the lack of important physical parameters such as the fissure width and the distance between the monitoring point and the fissure. A simulation for the period 1959–2004 showed some correlation between peaks in the simulated heads and the recorded occurrence of landslides while the bottom of the varved clays remained saturated during the entire simulation period.
The CORA dataset: validation and diagnostics of in-situ ocean temperature and salinity measurements
Authors: Cabanes C. , Grouazel A. , von Schuckmann K. , Hamon M. , Turpin V. , Coatanoan C. , Paris F. , Guinehut S. , Boone C. , Ferry N. , de Boyer Montégut C. , Carval T. , Reverdin G. , Pouliquen S. , Le Traon P.-Y.
Published: January 2013

Abstract. The French program Coriolis, as part of the French operational oceanographic system, produces the COriolis dataset for Re-Analysis (CORA) on a yearly basis. This dataset contains in-situ temperature and salinity profiles from different data types. The latest release CORA3 covers the period 1990 to 2010. Several tests have been developed to ensure a homogeneous quality control of the dataset and to meet the requirements of the physical ocean reanalysis activities (assimilation and validation). Improved tests include some simple tests based on comparison with climatology and a model background check based on a global ocean reanalysis. Visual quality control is performed on all suspicious temperature and salinity profiles identified by the tests, and quality flags are modified in the dataset if necessary. In addition, improved diagnostic tools have been developed – including global ocean indicators – which give information on the quality of the CORA3 dataset and its potential applications. CORA3 is available on request through the MyOcean Service Desk (http://www.myocean.eu/).
Oceanic dominance of interannual subtropical North Atlantic heat content variability
Authors: Sonnewald M. , Hirschi J. J.-M. , Marsh R.
Published: January 2013

Abstract. Ocean heat content varies on a range of timescales. Traditionally the atmosphere is seen to dominate the oceanic heat content variability. However, this variability can be driven either by oceanic or atmospheric heat fluxes. To diagnose the relative contributions and respective timescales, this study uses a box model forced with output from an ocean general circulation model (OGCM) to investigate the heat content variability of the upper 800 m of the subtropical North Atlantic from 26° N to 36° N. The ocean and air-sea heat flux data needed to force the box model is taken from a 19 yr (1988 to 2006) simulation performed with the 1/12° version of the OCCAM OGCM. The box model heat content is compared to the corresponding heat content in OCCAM for verification. The main goal of the study is to identify to what extent the seasonal to interannual ocean heat content variability is of atmospheric or oceanic origin. To this end, the box model is subjected to a range of scenarios forced either with the full (detrended) ocean and air-sea fluxes, or their deseasoned counterparts. Results show that in all cases, the seasonal variability is dominated by the seasonal component of the air-sea fluxes, which produce a seasonal range in mean temperature of the upper 800 m of ~ 0.42 °C. However, on longer timescales oceanic heat transport dominates, with changes of up to ~ 0.30 °C over 4 yr. The technique is subsequently applied to observational data. For the ocean heat fluxes, we use data from the RAPID program at 26° N from April 2004 to January 2011. At 36° N heat transport is inferred using a linear regression model based on the oceanic low-frequency transport in OCCAM. The air-sea flux from OCCAM is used for the period 2004 to 2006 when the RAPID timeseries and the OCCAM simulation overlap, and a climatology is used for the air-sea flux from 2006 onwards. The results confirm that on longer (> 2 yr) timescales the ocean dominates the ocean heat content variability, which is further verified using data from the ARGO project. This work illustrates that oceanic divergence significantly impacts the ocean heat content variability on timescales relevant for applications such as seasonal hurricane forecasts.
Unmet Visual Needs of Children with down Syndrome in an African Population: Implications for Visual and Cognitive Development
Authors: Aghaji Ada E. , Lawrence Linda , Ezegwui Ifeoma , Onwasigwe Ernest , Okoye Onochie , Ebigbo Peter
Published: January 2013

Purpose

TO determine the magnitude and types of ocular disorders in children with Down syndrome in an African population and to assess to what extent these visual needs have been met.

Methods

This is a cross-sectional study of children with Down syndrome attending a school for the mentally challenged in Southeastern Nigeria. Visual acuity, ocular examination, and cycloplegic refraction were done on all cooperative participants. Information was sought from parents/caregivers to ascertain previous ocular treatment/spectacle usage.

Results

A total of 30 children with Down syndrome aged 5–15 years were examined. Uncorrected refractive errors were detected in 76.4% of them. Other lesions included mongoloid slant (53.5%), strabismus (33.3%), ptosis (33.3%), nystagmus (13.3%), and cataract (3.3%). None of the children with refractive errors had ever worn spectacles.

Conclusions

Refractive error is a common finding in this population. There is a high unmet visual need in these children. This may have implications for visual and cognitive development. Early screening for ocular disorders in Down syndrome is recommended to detect and treat them.
Mapping of the Snuffbox and Cubital Vessels for Percutaneous Arterial Venous Fistula (pAVF) in Dialysis Patients
Authors: Hull Jeffrey E. , Kinsey Emily N. , Bishop Wendy L.
Published: January 2013

Purpose

Report on the anatomic qualification of the snuffbox radial artery (SBRA) and proximal radial artery (PRA) for pAVF.

Methods

Retrospective analysis of upper extremity mapping in 64 limbs in 55 dialysis patients was performed. The radial artery was assessed for diameter, patency, flow and proximity to the adjacent vein to SBRA and PRA. Sites qualified for pAVF on a binary basis when the in situ radial artery and adjacent vein were straight, parallel, greater than 2 mm in diameter and within 1.5 mm of each other. Effect of age, sex, diabetes, systolic blood pressure and obesity were assessed with logistic regression. Mean, median and frequency distribution of vessel diameter and distance were analyzed.

Results

Radial artery sites were qualified for pAVF in 47.6% (30/63) at the SBRA and 87.9% (29/33) at the PRA. SBRA sites were disqualified for vessel size in 36.4% (12/33 overall, usually vein 11/12), distance in 24% (8/33) and both 36.4% (12/33). All (4/4) PRA sites were disqualified for vessel size alone. The adjacent vein was the median vein or cephalic vein for the SBRA, and the perforating vein or vena comitans for the PRA. Effects of age, sex, diabetes, systolic blood pressure, obesity and prior fistula did not attain statistical significance.

Conclusions

Most dialysis patients meet the anatomic requirements for pAVF in the SBRA or PRA. Vessel size is the most common limiting variable followed by distance between vessels.
Market Restructuring, Competition and the Efficiency of Electricity Generation: Plant-level Evidence from the United States 1996 to 2006
Authors: Dean Craig J. , Savage Scott J.
Published: January 2013

This paper examines the effects of market restructuring initiatives that introduced competition into the United States electricity industry on the thermal efficiency of electricity generation. An empirical model is estimated on annual data for over 950 plants from 1996 to 2006. Model estimates show that access to wholesale electricity markets and retail choice together increased the efficiency of investor-owned plants by about nine percent and that these gains stem from organizational and technological changes within the plant. Although not directly targeted by restructuring initiatives, similar efficiency gains are also found for municipality-owned plants. This result suggests that the potential benefits from competition have spilled over to public electricity generation.
[BMIm][Fe(OTf)3], [BMIm][Mn(OTf)3], [BMIm][Li(OTf)2] – Three One-dimensional Infinite Coordination Polymers
Authors: Wolf Silke , Lan Yanhua , Powell Annie , Feldmann Claus
Published: January 2013

By heating of FeCl2 and MnCl2 in the ionic liquid [BMIm][OTf] (BMIm: 1-butyl-3- methylimidazolium, OTf: trifluoromethanesulfonate), the compounds [BMIm][M(OTf)3] (M: Fe+II, Mn+II) have been obtained as colorless crystals. Similarly, [BMIm][Li(OTf)2] was synthesized by heating of LiCl in [BMIm][OTf]. While the crystal quality of the [BMIm][M(OTf)3] (M: Fe+II, Mn+II) products thus obtained is low, mild oxidation of Fe(CO)5 or Mn2(CO)10 with GeI4 applied as an alternative in the same ionic liquid allowed a slow growth of well-formed, needle-shaped crystals. According to X-ray structure analysis based on single crystals, [BMIm][M(OTf)3] (M: Fe+II, Mn+II) crystals are monoclinic, and [BMIm][Li(OTf)2] crystals are triclinic. All compounds form infinite 1
∞[M(OTf)3] (M=Fe, Mn) and 1
∞[Li(OTf)2] chains. The compounds have further been characterized by FT-IR spectroscopy, energy-dispersive X-ray analysis (EDX), differential thermal analysis (DTA), thermogravimetry (TG), and magnetic measurements.
Formation and Fragmentation of 4-Diazo-1,2-diphenyl-3-oxo-butyl Acetate
Authors: Özbilen Deniz , Beile Bernhard , Meier Herbert
Published: January 2013

threo-4-Diazo-1,2-diphenyl-3-oxo-butyl acetate (15) could be prepared via the classical route 6→8→10→12→13→15. However, its alkaline hydrolysis to the bifunctional hydroxy compound 17 led to a spontaneous dehydration to the diazoketone (E)-18 and to a fragmentation to acetic acid, benzaldehyde (8) and diazoketone 19.
Electronic Structure and Bonding in YTi2Ga4 – A Gallide with Linear Titanium Chains and Four-bonded Gallium Atoms
Authors: Matar Samir F. , Pöttgen Rainer
Published: January 2013

The gallium-rich ternary intermetallic compound YTi2Ga4 is isotypic with YbMo2Al4, I4/mmm, Z =2. Yttrium is located in a large cage built up by 12 gallium atoms. Chains of condensed Y@Ga12 polyhedra and linear titanium chains build up a tetragonal rod packing. The gallium atoms are bonded within Ga4 squares (265 pm Ga-Ga) which are condensed via longer Ga-Ga bonds (292 pm) to a three-dimensional gallium substructure with formally four-connected gallium, in agreement with a Bader charge partitioning scheme [YTi2]4+[Ga4]4-. These features are addressed with electronic structure and chemical bonding considerations. The metallic behavior of YTi2Ga4 is found to be of the itinerant electron type within the valence band and Ti d-like states at EF. Ga-Ga and Ti-Ga bonding characteristics provide mechanical properties derived from the full set of elastic constants leading to a brittle material.
Joint Solution for the Online 3D Photorealistic Mapping Using SfM and SLAM
Authors: Choi Hyunga , Jun ChangHyun , Li Yuen Shang , Cho HyunGi , Doh Nakju Lett
Published: January 2013

This paper proposes a novel hybrid solution of SfM (Structure from Motion) and SLAM (Simultaneous Localization And Mapping) for the online generation of a 3D photorealistic map. As it is well known, the SfM can generate a 3D photo map, but it is difficult to get the real-scale as well as to build an online map (i.e., the map cannot be generated on the fly). In contrast, while SLAM frameworks are suitable for online real-scale mapping, they are not adequate for 3D photo map generation. To create a synergy effect, the proposed method combines SfM and SLAM. The way of combination is to use SfM for the generation of local maps and to utilize SLAM for a fusion of local maps in a globally consistent manner. Experimental results show that the proposed hybrid approach enables online 3D photorealistic mapping.
Stability Analysis of a Voltage-Based Controller for Robot Manipulators
Authors: Orrante-Sakanassi Jorge , Santibañez Victor , Moreno-Valenzuela Javier
Published: January 2013

A voltage-based control scheme for robot manipulators has been presented in recent literature, where feedback linearization is applied in the electrical equations of the DC motors in order to cancel the electrical current terms. However, in this paper we show that this control technique generates a system of the form Ex = Ax + Bu, where E is a singular matrix, that is to say, a generalized state-space system or singular system. This paper introduces a formal stability analysis of the respective system by considering the state-space equation as a singular system. Furthermore, in order to avoid the singularity of the closed-loop system, modified voltage-based control schemes are proposed, whose Lyapunov stability analyses conclude semiglobal asymptotic stability for the set-point control case and uniform boundedness of the solutions and semiglobal convergence of the position, as well as velocity errors for the tracking control case. The proposed control systems are simulated for the tracking and set-point cases using the CICESE Pelican robot driven by DC motors.
Speech-Based Human and Service Robot Interaction: An Application for Mexican Dysarthric People
Authors: Morales Santiago Omar Caballero , Enríquez Gladys Bonilla , Romero Felipe Trujillo
Published: January 2013

Dysarthria is a motor speech disorder due to weakness or poor coordination of the speech muscles. This condition can be caused by a stroke, traumatic brain injury, or by a degenerative neurological disease. Commonly, people with this disorder also have muscular dystrophy, which restricts their use of switches or keyboards for communication or control of assistive devices (i.e., an electric wheelchair or a service robot). In this case, speech recognition is an attractive alternative for interaction and control of service robots, despite the difficulty of achieving robust recognition performance. In this paper we present a speech recognition system for human and service robot interaction for Mexican Spanish dysarthric speakers. The core of the system consisted of a Speaker Adaptive (SA) recognition system trained with normal-speech. Features such as on-line control of the language model perplexity and the adding of vocabulary, contribute to high recognition performance. Others, such as assessment and text-to-speech (TTS) synthesis, contribute to a more complete interaction with a service robot. Live tests were performed with two mild dysarthric speakers, achieving recognition accuracies of 90–95% for spontaneous speech and 95–100% of accomplished simulated service robot tasks.
Hydrodynamic Performance of an Undulatory Robot: Functional Roles of the Body and Caudal Fin Locomotion
Authors: Wen Li , Liang Jianhong , Shen Qi , Bao Lei , Zhang Qian
Published: January 2013

Both body undulation and caudal fin flapping play essential locomotive roles while a fish is swimming, but how these two affect the swimming performance and hydrodynamics of fish individually is yet to be known. We implemented a biomimetic robotic fish that travel along a servo towing system, which can be regarded as “treadmill” of the model. Hydrodynamics was studied as a function of the principal kinetic parameters of the undulatory body and caudal fin of the model in a self-propelled condition, under which the time-averaged measured axial net force becomes zero. Thrust efficiency was estimated from two-dimensional digital particle image velocimetry (DPIV) measurements in the horizontal and mid-caudal fin plane. The Single-Row Reverse Karman wake (2S) is commonly observed in many previous studies of live fish swimming. However, we show that a Double-Row Two-Paired vortices (2P) wake was generated by the robotic model for most kinetic parameter combinations. Interestingly, the 2S wake emerged within the results of a narrow range of robotic caudal fin pitch angles (0<0<10°), occurring concurrently with enhanced thrust efficiency. We also show that, compared with the effect of body wavelength ( ?), the wake structure behind the robotic swimmer is more sensitive to the Strouhal number ( St) and caudal fin pitch angle ( θ).
Effective Structure Learning for Estimation of Distribution Algorithms via L1-Regularized Bayesian Networks
Authors: Xu Hua , Yang Jiadong , Jia Peifa , Ding Yi
Published: January 2013

Estimation of distribution algorithms (EDAs), as an extension of genetic algorithms, samples new solutions from the probabilistic model, which characterizes the distribution of promising solutions in the search space at each generation. This paper introduces and evaluates a novel estimation of a distribution algorithm, called L1-regularized Bayesian optimization algorithm, L1BOA. In L1BOA, Bayesian networks as probabilistic models are learned in two steps. First, candidate parents of each variable in Bayesian networks are detected by means of L1-regularized logistic regression, with the aim of leading a sparse but nearly optimized network structure. Second, the greedy search, which is restricted to the candidate parent-child pairs, is deployed to identify the final structure. Compared with the Bayesian optimization algorithm (BOA), L1BOA improves the efficiency of structure learning due to the reduction and automated control of network complexity introduced with L1-regularized learning. Experimental studies on different types of benchmark problems show that L1BOA not only outperforms BOA when no prior knowledge about problem structure is available, but also achieves and even exceeds the best performance of BOA that applies explicit controls on network complexity. Furthermore, Bayesian networks built by L1BOA and BOA during evolution are analysed and compared, which demonstrates that L1BOA is able to build simpler, yet more accurate probabilistic models.
A Quadratic Nonlinear Prediction-Based Heart Motion Model following Control Algorithm in Robotic-Assisted Beating Heart Surgery
Authors: Liang Fan , Meng Xiaofeng
Published: January 2013

Off-pump coronary artery bypass graft surgery outperforms the traditional on-pump surgery because the assisted robotic tools can cancel the relative motion between the beating heart and the robotic tools, which reduces post-surgery complications for patients. The challenge for the robot assisted tool when tracking the beating heart is the abrupt change caused by the nonlinear nature of heart motion and high precision surgery requirements. A characteristic analysis of 3D heart motion data through bi-spectral analysis demonstrates the quadratic nonlinearity in heart motion. Therefore, it is necessary to introduce nonlinear heart motion prediction into the motion tracking control procedures. In this paper, the heart motion tracking problem is transformed into a heart motion model following problem by including the adaptive heart motion model into the controller. Moreover, the model following algorithm with the nonlinear heart motion model embedded inside provides more accurate future reference by the quadratic term of sinusoid series, which could enhance the tracking accuracy of sharp change point and approximate the motion with sufficient detail. The experiment results indicate that the proposed algorithm outperforms the linear prediction-based model following controller in terms of tracking accuracy (root mean square).
Heterogeneous Context-Aware Robots Providing a Personalized Building Tour
Authors: Hristoskova Anna , Agüero Carlos E. , Veloso Manuela , De Turck Filip
Published: January 2013

Existing robot guides offer a tour of a building, such as a museum or science centre, to one or more visitors. Usually the tours are predefined and lack support for dynamic interactions between the different robots.

This paper focuses on the distributed collaboration of multiple heterogeneous robots (receptionist, companion) guiding visitors through a building. Semantic techniques support the formal definition of tour topics, the available content on a specific topic, and the robot and person profiles including interests and acquired knowledge. The robot guides select topics depending on their participants' interests and prior knowledge. Whenever one guide moves into the proximity of another, the guides automatically exchange participants, optimizing the amount of interesting topics.

Robot collaboration is realized through the development of a software module that allows a robot to transparently include behaviours performed by other robots into its own set of behaviours. The multi-robot visitor guide application is integrated into an extended distributed heterogeneous robot team, using a receptionist robot that was not originally designed to cooperate with the guides.

Evaluation of the implemented algorithms presents a 90% content coverage of relevant topics for the participants.
Visualizing multiphase flow and trapped fluid configurations in a model three‐dimensional porous medium
Authors: Krummel Amber T. , Datta Sujit S. , Münster Stefan , Weitz David A.
Published: January 2013

We report an approach to fully visualize the flow of two immiscible fluids through a model three‐dimensional (3‐D) porous medium at pore‐scale resolution. Using confocal microscopy, we directly image the drainage of the medium by the nonwetting oil and subsequent imbibition by the wetting fluid. During imbibition, the wetting fluid pinches off threads of oil in the narrow crevices of the medium, forming disconnected oil ganglia. Some of these ganglia remain trapped within the medium. By resolving the full 3‐D structure of the trapped ganglia, we show that the typical ganglion size, as well as the total amount of residual oil, decreases as the capillary number Ca increases; this behavior reflects the competition between the viscous pressure in the wetting fluid and the capillary pressure required to force oil through the pores of the medium. This work thus shows how pore‐scale fluid dynamics influence the trapped fluid configurations in multiphase flow through 3‐D porous media. © 2013 American Institute of Chemical Engineers AIChE J, 59:1022‐1029, 2013
Optimal Design of Generalized Batch‐Storage Network Considering Shortage Costs
Authors: Yi Gyeongbeom , Reklaitis Gintaras V.
Published: January 2013

Product shortages, which cause backlogging and/or lost sales costs commonly occur in the chemical industries, especially in the commodity polymer business. Shortage costs in a supply chain optimization model are studied under the framework of a generalized batch‐storage network. A classical economic order quantity model with backlogging costs suggested an optimal time delay and final product delivery lot size. A product shortage can be mitigated by advancing production/transportation or by purchasing a substitute product from a third party as well as by a product delivery delay in the supply chain network. Optimal solutions that consider all means for recovering shortage are more complicated than the classical case. Four solutions are identified depending on the parametric range and variable bounds. The optimal capacity for production/transportation processes associated with a product in shortage can differ from that of a product not in shortage. An illustrative example is presented in support of the analytical results. © 2013 American Institute of Chemical Engineers AIChE J, 59: 2454–2470, 2013
CaCO3 fouling on microscale–nanoscale hydrophobic titania–fluoroalkylsilane films in pool boiling
Authors: Cai Yongwei , Liu Mingyan , Hui Longfei
Published: January 2013

Micrometer–nanometer hydrophobic titania–fluoroalkylsilane composite coatings were prepared on substrates based on liquid‐phase deposition. Coatings and crystallization forms were characterized with instruments of surface analyses. Experimental facilities of pool boiling were established to evaluate heat and mass transfer on coated surfaces in deionized water and saturated calcium carbonate solution. Obvious pool boiling enhancement was observed on thinner microscale–nanoscale hydrophobic titania–fluoroalkylsilane composite films at higher heat fluxes compared to that on thicker titania–fluoroalkylsilane coatings or on titania coatings and stainless steel surfaces. Lower fouling resistance was obtained on titania–fluoroalkylsilane coatings in pool boiling of saturated calcium carbonate solution and crystal form was aragonite, which was different from calcite on titania coatings. Results of inhibition of fouling and enhancement of heat transfer on titania–fluoroalkylsilane coatings were contributed to special surface microscale–nanoscale structure and material wettability. Asymptotic model was used to fit experimental data of fouling resistance, and reasonable agreement was obtained. © 2013 American Institute of Chemical Engineers AIChE J, 59: 2662–2678, 2013
Fluctuations, Order, and Disorder in Short Diblock Copolymers
Authors: Lee Sangwoo , Gillard Timothy M. , Bates Frank S.
Published: January 2013

The phase behavior for a series of poly(1,4‐isoprene‐b‐DL‐lactide) diblock copolymers characterized by a relatively large Flory–Huggins segment–segment interaction parameter (χ) and low degrees of polymerization (N) over a range of compositions was reported. Ordered‐state morphologies were deduced from small‐angle x‐ray scattering (SAXS) measurements, and χ(T) was determined from order‐disorder transition temperatures (TODT's) associated with the compositionally symmetric specimens and assuming the mean‐field theory, that is, (χN)ODT=10.5. The ODT was determined by differential scanning calorimetry, SAXS, and dynamic mechanical spectroscopy, and shown to be weakly first‐order, with latent heats of transition that vary strongly with composition. We interpret this behavior in terms of the mean and Gauss interfacial curvature of the ordered‐state morphologies and with respect to composition fluctuations in the disordered state. These results offer a fresh strategy for investigating weakly first‐order phase transitions within the Brazovskii universality class. © 2013 American Institute of Chemical EngineersAIChE J, 59: 3502–3513, 2013
A new dry tray pressure drop model of float valve trays
Authors: Wang Jun , Tang Yi‐Xuan , Liu Yan‐Sheng , Cao Rui , Chen Tian‐Xin , Hu Yu‐Feng , Fan Xue‐Jun
Published: January 2013

An accurate prediction of the dry pressure drop is very important for consideration of valve trays and for calculations in distillation field. Therefore, in this article, a series of hydraulic experiments were first conducted to reveal that the intermediate state during the valve opening process is closely related to the dry tray pressure drop under great valve weight. Then, a rigorous force analysis was made to show that Euler number is related only to the valve's position at the balance points for a certain valve type. Third, a new model for prediction of the dry tray pressure drop—which considers for the first time the influence of the intermediate state—was developed and then simplified for the purpose of convenient utilizations. Finally, the new model and its simplified form were tested by comparisons with the experimental results. The agreements are good, with the mean deviations being <5%. © 2013 American Institute of Chemical Engineers AIChE J, 59: 2694–2705, 2013
Complex craniosynostosis is associated with the 2p15p16.1 microdeletion syndrome
Authors: Florisson Joyce M.G. , Mathijssen Irene M.J. , Dumee Belinda , Hoogeboom Jeannette A.M. , Poddighe Pino J. , Oostra Ben A. , Frijns Jean Pierre , Koster Linda , de Klein Annelies , Eussen Bert , de Vries Bert B.A. , Swagemakers Sigrid , van der Spek Peter J. , Verkerk Annemieke J.M.H.
Published: January 2013

In a screening project of patients with (complex) craniosynostosis using genomic arrays, we identified two patients with craniosynostosis and microcephaly with a deletion in the 2p15p16.1 chromosomal region. This region has been associated with a new microdeletion syndrome, for which patients have various features in common, including microcephaly and intellectual disability. Deletions were identified using Affymetrix 250K SNP array and further characterized by fluorescence in situ hybridization (FISH) analysis and qPCR. The deletions in our two patients overlapped within the 2p15p16.1 microdeletion syndrome area and were 6.8 and 6.9 Mb in size, respectively. FISH and qPCR confirmed the presence of only one copy in this region. Finemapping of the breakpoints indicated precise borders in our patients and were further finemapped in two other previously reported patients. Clinical features of patients with deletions in the 2p15p16.1 region vary. Including data from our patients, now eight out of nine reported patients have microcephaly, one of the major features, and all had intellectual disability. The current reported two patients add different forms of craniosynostosis to the clinical spectrum of this recently recognized microdeletion syndrome. © 2013 Wiley Periodicals, Inc.
A family with a complex clinical presentation characterized by arrhythmogenic right ventricular dysplasia/cardiomyopathy and features of branchio‐oculo‐facial syndrome
Authors: Murray Brittney , Wagle Rohan , Amat‐Alarcon Nuria , Wilkens Alisha , Stephens Paul , Zackai Elaine H. , Goldmuntz Elizabeth , Calkins Hugh , Deardorff Matthew A. , Judge Daniel P.
Published: January 2013

Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is a familial form of cardiomyopathy typically caused by mutations in genes that encode an element of the cardiac desmosome. Branchio‐oculo‐facial syndrome (BOFS) is a craniofacial disorder caused by TFAP2A mutations. In a family segregating ARVD/C, some members also had features of BOFS. Genetic testing for ARVD/C identified a mutation in PKP2, encoding plakophilin‐2, a component of the cardiac desmosome. Evaluation of dysmorphology by chromosome microarray (CMA) identified a 4.4 Mb deletion at chromosome 6p24 that included both TFAP2A and DSP, encoding desmoplakin, an additional component of the cardiac desmosome implicated in ARVD/C. A family member with both the 6p24 deletion and PKP2 mutation had more severe cardiac dysfunction. These findings suggest that this contiguous gene deletion contributes to both ARVD/C and BOFS, and that DSP haploinsufficiency may contribute to cardiomyopathy. This family provides a clinical example that underscores the need for careful evaluation in clinical scenarios where genetic heterogeneity is known to exist. Finally, it suggests that individuals with unexplained cardiomyopathy and dysmorphic facial features may benefit from CMA analysis. © 2013 Wiley Periodicals, Inc.
The Bonobo–Dialium Positive Interactions: Seed Dispersal Mutualism
Authors: BEAUNE DAVID , BRETAGNOLLE FRANÇOIS , BOLLACHE LOÏC , HOHMANN GOTTFRIED , SURBECK MARTIN , BOURSON CHLOÉ , FRUTH BARBARA
Published: January 2013

A positive interaction is any interaction between individuals of the same or different species (mutualism) that provides a benefit to both partners such as increased fitness. Here we focus on seed dispersal mutualism between an animal (bonobo, Pan paniscus) and a plant (velvet tamarind trees, Dialium spp.). In the LuiKotale rainforest southwest of Salonga National Park, Democratic Republic of Congo, seven species of the genus Dialium account for 29.3% of all trees. Dialium is thus the dominant genus in this forest. Dialium fruits make up a large proportion of the diet of a habituated bonobo community in this forest. During the 6 months of the fruiting season, more than half of the bonobos’ feeding time is devoted to Dialium fruits. Furthermore, Dialium fruits contribute a considerable proportion of sugar and protein to bonobos’ dietary intake, being among the richest fruits for these nutrients. Bonobos in turn ingest fruits with seeds that are disseminated in their feces (endozoochory) at considerable distances (average: 1.25 km after 24 hr of average transit time). Endozoochory through the gut causes loss of the cuticle protection and tegumentary dormancy, as well as an increase in size by water uptake. Thus, after gut passage, seeds are better able to germinate. We consider other primate species as a potential seed disperser and conclude that Dialium germination is dependent on passage through bonobo guts. This plant–animal interaction highlights positive effects between two major organisms of the Congo basin rainforest, and establishes the role of the bonobo as an efficient disperser of Dialium seeds. Am. J. Primatol. 75:394‐403, 2013. © 2013 Wiley Periodicals, Inc.
The association between allergic rhinitis and sleep‐disordered breathing in children: a systematic review
Authors: Lin Sandra Y. , Melvin Thuy‐Anh N. , Boss Emily F. , Ishman Stacey L.
Published: January 2013

Background

The objective of this work was to systematically review existing literature on the association between allergic rhinitis (AR) and sleep‐disordered breathing (SDB) in children.

Methods

We performed a literature search encompassing the last 25 years in PubMed, EMBASE, and Cochrane CENTRAL. Inclusion criteria included English‐language papers containing original human data, number of subjects ≥7, and age <18 years old. Data was systematically collected on study design, patient demographics, clinical characteristics/outcomes, and level‐of‐evidence. Two investigators independently reviewed all articles.

Results

The initial search yielded 433 abstracts, of which 18 articles were included. Twelve (67%) of the 18 articles showed a statistically significant association between AR and SDB. All articles were either case‐series or case‐control studies. Based on the Newcastle‐Ottawa scale, the quality of the articles was determined to be fair to good. For characterizing AR, 7 (39%) studies included skin‐prick testing and/or in vitro testing. For determining presence of SDB, 7 (39%) of the studies used polysomnographic data, of which 1 study incorporated data from a home polysomnogram. Habitual snoring was the most common form of SDB studied, in 10 (56%) of the articles. Obstructive sleep apnea was studied in 6 (33%) articles.

Conclusion

Although the majority of the studies included in this review showed a significant association between AR and SDB, all of the studies were evidence level 3b and 4, for an overall grade of B− evidence (Oxford Evidence‐Based Medicine Center). Further higher‐quality studies should be performed in the future to better evaluate the relationship between AR and SDB in children.
Brownian motion at short time scales
Authors: Li Tongcang , Raizen Mark G.
Published: January 2013

Brownian motion has played important roles in many different fields of science since its origin was first explained by Albert Einstein in 1905. Einstein's theory of Brownian motion, however, is only applicable at long time scales. At short time scales, Brownian motion of a suspended particle is not completely random, due to the inertia of the particle and the surrounding fluid. Moreover, the thermal force exerted on a particle suspended in a liquid is not a white noise, but is colored. Recent experimental developments in optical trapping and detection have made this new regime of Brownian motion accessible. This review summarizes related theories and recent experiments on Brownian motion at short time scales, with a focus on the measurement of the instantaneous velocity of a Brownian particle in a gas and the observation of the transition from ballistic to diffusive Brownian motion in a liquid.
Predicting population status of freshwater pearl mussel (Margaritifera margaritifera, L.) in central Sweden using instream and riparian zone land‐use data
Authors: Degerman E. , Andersson K. , Söderberg H. , Norrgrann O. , Henrikson L. , Angelstam P. , Törnblom J.
Published: January 2013

The freshwater pearl mussel Margaritifera margaritifera (L.) has become scarce and threatened throughout most of its distribution range, and is consequently listed as ‘endangered’ by the IUCN. It has been suggested and used as an indicator species and even as an umbrella species. Despite this, few studies have examined factors affecting its catchment‐level population status.

This work tested the hypothesis that it is possible to predict freshwater pearl mussel population viability (reproducing/not reproducing) and population status in central Sweden from a combination of geospatial data describing riparian land‐cover and use, water chemistry data, and electrofishing data describing the abundance of the host fish species (brown trout, Salmo trutta) in 56 streams.

Mussel population viability was best predicted by total phosphorus. Using higher‐resolution data (six classes) on mussel population status, host fish abundance (0+ trout) was the best predictor. At abundances below 5 0+ trout per 100 m2 and above a concentration of 8 µg L–1 total phosphorus, only three viable populations existed.

Geospatial data could be used to predict levels of total phosphorus and thereby indirectly to predict mussel viability. Geospatial data could not be used to predict abundance of 0+ trout, which is thought to depend more on instream factors. This study demonstrates that geospatial data on riparian land‐use and cover can be a useful tool for screening waters potentially harbouring non‐reproducing mussel populations.

Copyright © 2013 John Wiley & Sons, Ltd.
Nuclear Accumulation of Prohibitin 1 in Osteoarthritic Chondrocytes Down‐Regulates PITX1 Expression
Authors: Picard Cynthia , Pellicelli Martin , Taheri Maryam , Lavoie Jean‐Francois , Doucet Roxanne , Wang DaShen , Bernard Lauriane , Bouhanik Saadallah , Lavigne Patrick , Moreau Alain
Published: January 2013

Objective

To decipher the molecular mechanisms down‐regulating PITX1 expression in primary osteoarthritis (OA).

Methods

The functional activity of different PITX1 promoter regions was assessed by luciferase reporter assay. Tandem mass spectrometry coupled to protein sequencing was performed using nuclear extracts prepared from OA chondrocytes, in order to identify proteins bound to DNA regulatory elements. Expression analyses of selected candidate proteins were performed by real‐time reverse transcription–polymerase chain reaction (RT‐PCR) and immunohistochemistry methods, using cartilage sections and articular chondrocytes from non‐OA control subjects and patients with OA. Gain‐of‐function and loss‐of‐function experiments were performed in normal and OA chondrocytes, respectively, to study their effects on PITX1 regulation. The results were validated by real‐time RT‐PCR and immunohistochemistry in STR/Ort mice, a well‐known animal model of OA.

Results

PITX1 promoter analyses led to the identification of prohibitin 1 (PHB1) bound to a distal E2F1 transcription factor site. Aberrant accumulation of PHB1 was detected in the nuclei of OA articular chondrocytes, and overexpression of PHB1 in control cells was sufficient to inhibit endogenous PITX1 expression at the messenger RNA and protein levels. Conversely, knockdown of PHB1 in OA articular chondrocytes resulted in up‐regulation of PITX1. Studies of early molecular changes in STR/Ort mice revealed a similar nuclear accumulation of PHB1, which correlated with Pitx1 repression.

Conclusion

Collectively, these data define an unrecognized role for PHB1 in repressing PITX1 expression in OA chondrocytes.
Analyzing structural stratification in the Swedish higher education system: Data contextualization with policy‐history analysis
Authors: Hallonsten Olof , Holmberg Daniel
Published: January 2013

20th century massification of higher education and research in academia is said to have produced structurally stratified higher education systems in many countries. Most manifestly, the research mission of universities appears to be divisive. Authors have claimed that the Swedish system, while formally unified, has developed into a binary state, and statistics seem to support this conclusion. This article makes use of a comprehensive statistical data source on Swedish higher education institutions to illustrate stratification, and uses literature on Swedish research policy history to contextualize the statistics. Highlighting the opportunities as well as constraints of the data, the article argues that there is great merit in combining statistics with a qualitative analysis when studying the structural characteristics of national higher education systems. Not least the article shows that it is an over‐simplification to describe the Swedish system as binary; the stratification is more complex. On basis of the analysis, the article also argues that while global trends certainly influence national developments, higher education systems have country‐specific features that may enrich the understanding of how systems evolve and therefore should be analyzed as part of a broader study of the increasingly globalized academic system.
Coding Scheme Based on Boundary Functions for Distributed System with Finite Channel Data Rates and Packet Dropouts
Authors: Jian Wang , Zhibin Yan , Jiafeng Yu
Published: January 2013

This paper considers discrete linear systems with multiple distributed sensors that are connected to one controller via channels of finite data rate. Each encoder has access to only one component of the current system output vector. By the proposed boundary function method, a condition expressed in terms of output feedback gain matrix, the parameters of boundary functions, and the channel data rates is given to guarantee the convergence of the state in the case of reliable channels. Then, we extend the result to the case of erasure channels.
Self‐Repairing Control Against Unknown Sensor Failures and Biases
Authors: Takahashi Masanori
Published: January 2013

In this paper, a self‐repairing control system (SRCS) is presented for a plant with unknown sensor failure and bias. The simultaneous use of an unstable filter and a differential filter makes a monitored signal hit the prescribed threshold whenever the failure of a stuck‐type occurs. Then, the failed sensor can be found exactly, and be switched to the healthy backup. The advantage of the method is that any information about the plants for fault detection is not necessary. Also, the introduction of the differential filter can eliminate the effect of the sensor bias. Thus, the SRCS copes with the problems on both sensor failures and biases. Through several numerical simulations, the effectiveness of the proposed SRCS is confirmed.