bluuebunny/crossref_metadata_2025 huggingface dataset:
Quiet and Disturbed Time Characteristics of Blanketing Es (Esb) During Solar Cycle 23
Authors: Yadav V. , Kakad B. , Bhattacharyya A. , Pant T. K.
Published: October 2017

A sporadic E layer with dense ionization blocks the upper ionospheric layers in ionosonde observations and it is called, blanketing sporadic E (Esb). Although earlier studies have demonstrated that Esb occurrence is dependent on solar activity, seasons, local time, and equatorial electrojet/counter equatorial electrojet (EEJ/CEEJ) strength, the physics behind this dependence is not well established particularly at the dip equatorial stations. Moreover, fewer comprehensive studies are available on Esb. Present work is a detailed statistical study of Esb occurrence and its characteristics during solar cycle 23 (1996–2006) at Indian dip equatorial station Trivandrum (dip latitude 0.5°N). In present study, solar flux dependence of Esb occurrence is clearly evident not only for magnetically quiet but also for the disturbed periods with maximum during low solar activity. Known seasonal peak Esb occurrence during summer (May–August) is found to be dominated by larger percentage of total blanketing events (fbEs ≥ 8 MHz) on magnetically disturbed days as compared to quiet days. We noticed prevalent Esb occurrence in the postmidnight (00–06 India Standard Time) periods during low solar activity. Besides Esb characteristics, the present study aims to investigate effect of solar flux on association of Esb and CEEJ. Coexistence of Esb and CEEJ is emphasized in earlier observational studies. However, any dependence of their association on solar flux is not yet examined. We find that their association is weaker during low solar activity as compared to high solar activity in summer, indicating that Esb occurrence is highly likely on CEEJ days during high solar activity periods.
Structure and Properties of the Foreshock at Venus
Authors: Omidi N. , Collinson G. , Sibeck D.
Published: October 2017

The interaction of the solar wind with Venus is dominated by the planet's ionosphere that acts as an obstacle to the flow resulting in an induced magnetosphere and bow shock much smaller than their terrestrial counterparts. This study presents a 3‐D electromagnetic hybrid (kinetic ions and fluid electrons) simulation of the solar wind interaction with an unmagnetized obstacle to examine the structure and properties of the Cytherean foreshock during periods of near radial IMF, that is, when it lies upstream of the ionosphere. The interaction between the backstreaming ions and the solar wind results in the generation of two classes of ULF waves: (1) parallel propagating sinusoidal waves with periods ~20–30 s and (2) highly oblique fast magnetosonic waves. The joint nonlinear evolution of these waves results in the formation of structures called foreshock cavitons with dimensions comparable to the size of the planet. Foreshock cavitons are also present in the terrestrial foreshock. The excavation of plasma and magnetic field from their cores leads to lower average densities and magnetic field strengths in the foreshock. As in the case of Earth, this excavation results in the formation of a fast magnetosonic pulse/shock at the edge of the foreshock named the foreshock compressional boundary. Also similar to Earth is the formation of spontaneous hot flow anomalies (SHFAs) as foreshock cavitons approach the bow shock. The size and properties of SHFAs at Venus are comparable to those at Earth, and their existence has recently been established at Mars and Venus in a companion paper.
The Evolution of the Plasma Sheet Ion Composition: Storms and Recoveries
Authors: Denton M. H. , Thomsen M. F. , Reeves G. D. , Larsen B. A. , Henderson M. G. , Jordanova V. K. , Fernandes P. A. , Friedel R. H. W. , Skoug R. M. , Funsten H. O. , MacDonald E. A. , Spence H. A.
Published: October 2017

The ion plasma sheet (~few hundred eV to ~few tens keV) is usually dominated by H+ ions. Here changes in ion composition within the plasma sheet are explored both during individual events and statistically during 54 calm‐to‐storm events and during 21 active‐to‐calm events. Ion composition data from the HOPE (Helium, Oxygen, Proton, Electron) instruments onboard Van Allen Probes satellites provide exceptional spatial resolution and temporal resolution of the H+, O+, and He+ ion fluxes in the plasma sheet. H+ is shown to be the dominant ion in the plasma sheet in the calm‐to‐storm transition. However, the energy‐flux of each ion changes in a quasi‐linear manner during extended calm intervals. Heavy ions (O+ and He+) become increasingly important during such periods as charge‐exchange reactions result in faster loss for H+ than for O+ or He+. Results confirm previous investigations showing that the ion composition of the plasma sheet can be largely understood (and predicted) during calm intervals from knowledge of (a) the composition of previously injected plasma at the onset of calm conditions and (b) use of simple drift‐physics models combined with calculations of charge‐exchange losses.
Modeling Geomagnetically Induced Currents From Magnetometer Measurements: Spatial Scale Assessed With Reference Measurements
Authors: Butala Mark D. , Kazerooni Maryam , Makela Jonathan J. , Kamalabadi Farzad , Gannon Jennifer L. , Zhu Hao , Overbye Thomas J.
Published: October 2017

Solar‐driven disturbances generate geomagnetically induced currents (GICs) that can result in power grid instability and, in the most extreme cases, even failure. Magnetometers provide direct measurements of the geomagnetic disturbance (GMD) effect on the surface magnetic field and GIC response can be determined from the power grid topology and engineering parameters. This paper considers this chain of models: transforming surface magnetic field disturbance to induced surface electric field through an electromagnetic transfer function and, then, induced surface electric field to GIC using the PowerWorld simulator to model a realistic power grid topology. Comparisons are made to transformer neutral current reference measurements provided by the American Transmission Company. Three GMD intervals are studied, with the Kp index reaching 8− on 2 October 2013, 7 on 1 June 2013, and 6− on 9 October 2013. Ultimately, modeled to measured GIC correlations are analyzed as a function of magnetometer to GIC sensor distance. Results indicate that modeling fidelity during the three studied GMD intervals is strongly dependent on both magnetometer to substation transformer baseline distance and GMD intensity.
Data Assimilation in the Solar Wind: Challenges and First Results
Authors: Lang Matthew , Browne Philip , van Leeuwen Peter Jan , Owens Mathew
Published: October 2017

Data assimilation (DA) is used extensively in numerical weather prediction (NWP) to improve forecast skill. Indeed, improvements in forecast skill in NWP models over the past 30 years have directly coincided with improvements in DA schemes. At present, due to data availability and technical challenges, DA is underused in space weather applications, particularly for solar wind prediction. This paper investigates the potential of advanced DA methods currently used in operational NWP centers to improve solar wind prediction. To develop the technical capability, as well as quantify the potential benefit, twin experiments are conducted to assess the performance of the Local Ensemble Transform Kalman Filter (LETKF) in the solar wind model ENLIL. Boundary conditions are provided by the Wang‐Sheeley‐Arge coronal model and synthetic observations of density, temperature, and momentum generated every 4.5 h at 0.6 AU. While in situ spacecraft observations are unlikely to be routinely available at 0.6 AU, these techniques can be applied to remote sensing of the solar wind, such as with Heliospheric Imagers or interplanetary scintillation. The LETKF can be seen to improve the state at the observation location and advect that improvement toward the Earth, leading to an improvement in forecast skill in near‐Earth space for both the observed and unobserved variables. However, sharp gradients caused by the analysis of a single observation in space resulted in artificial wavelike structures being advected toward Earth. This paper is the first attempt to apply DA to solar wind prediction and provides the first in‐depth analysis of the challenges and potential solutions.
Modeling Geoelectric Fields and Geomagnetically Induced Currents Around New Zealand to Explore GIC in the South Island's Electrical Transmission Network
Authors: Divett T. , Ingham M. , Beggan C. D. , Richardson G. S. , Rodger C. J. , Thomson A. W. P. , Dalzell M.
Published: October 2017

Transformers in New Zealand's South Island electrical transmission network have been impacted by geomagnetically induced currents (GIC) during geomagnetic storms. We explore the impact of GIC on this network by developing a thin‐sheet conductance (TSC) model for the region, a geoelectric field model, and a GIC network model. (The TSC is composed of a thin‐sheet conductance map with underlying layered resistivity structure.) Using modeling approaches that have been successfully used in the United Kingdom and Ireland, we applied a thin‐sheet model to calculate the electric field as a function of magnetic field and ground conductance. We developed a TSC model based on magnetotelluric surveys, geology, and bathymetry, modified to account for offshore sediments. Using this representation, the thin sheet model gave good agreement with measured impedance vectors. Driven by a spatially uniform magnetic field variation, the thin‐sheet model results in electric fields dominated by the ocean‐land boundary with effects due to the deep ocean and steep terrain. There is a strong tendency for the electric field to align northwest‐southeast, irrespective of the direction of the magnetic field. Applying this electric field to a GIC network model, we show that modeled GIC are dominated by northwest‐southeast transmission lines rather than east‐west lines usually assumed to dominate.
Asymmetric Dearomative Halogenation of β‐Naphthols: The Axial Chirality Transfer Reaction
Authors: Wang Pengxin , Wang Jie , Wang Linqing , Li Dan , Wang Kezhou , Liu Yuyang , Zhu Haiyong , Liu Xihong , Yang Dongxu , Wang Rui
Published: October 2017

Axial naphthols are applied in asymmetric halogenative dearomatization reactions under simple and mild conditions in the work presented herein. The axial‐to‐central chirality conversion is efficiently accomplished, and the desired halogenated dearomatization products are obtained in high yields and enantioselectivities. By using commercially available halogenation reagents, the asymmetric fluorinative, chlorinative and brominative dearomatization reactions of axial naphthols derived from BINOLs are achieved. (BINOL=1,1′‐Bi‐2‐naphthol)

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Decarboxylative Synthesis of Functionalized Oxindoles via An Iron‐Initiated Radical Chain Process and Application in Constructing Diverse Fused‐Indoline Heterocycles
Authors: Cui Zhihao , Du Da‐Ming
Published: October 2017

Rapid construction of diverse fused‐indoline−heterocycle (FIH) frameworks including high‐value pyrroloindolines, furoindolines and thienoindolines in a two‐step sequence has been described. The key to success hinges on the adoption of peresters as α‐heteroatom alkyl radical precusors, which can smoothly react with N‐arylacrylamides via a radical chain process initiated by inexpensive FeCl2⋅4H2O to afford the functionalized oxindoles, the key intermediates to FIH skeletons. The approach features operationally‐simplicity, broad substrates scope and mild conditions.

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Three‐Component Thieno[2,3‐b]indole Synthesis from Indoles, Alkenes or Alkynes and Sulfur Powder under Metal‐Free Conditions
Authors: Li Bin , Ni Penghui , Huang Huawen , Xiao Fuhong , Deng Guo‐Jun
Published: October 2017

A Bronsted acid promoted three‐component synthesis of substituted thieno[2,3‐b]indole has been developed starting from indoles, alkenes or alkynes, and sulfur powder. N,N‐Dimethylformamide plays an important role to convert the starting materials into the fused products. Various functional groups attached to substrates were well tolerated to afford the corresponding products in moderate to good yields under very simple reaction conditions.

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High dose chemotherapy and autologous stem cell transplantation in nodular lymphocyte‐predominant Hodgkin lymphoma: A retrospective study by the European society for blood and marrow transplantation‐lymphoma working party
Authors: Akhtar Saad , Montoto Silvia , Boumendil Ariane , Finel Herve , Masszi Tamas , Jindra Pavel , Nemet Damir , Fuhrmann Stephan , Beguin Yves , Castagna Luca , Ferrara Felicetto , Capria Saveria , Malladi Ram , Moraleda Jose Maria , Bloor Adrian , Ghesquières Hervé , Meissner Julia , Sureda Anna , Dreger Peter
Published: October 2017

Whilst autologous stem cell transplantation (auto‐SCT) is considered standard of care for relapsed/refractory classical Hodgkin lymphoma, the role of auto‐SCT in nodular lymphocyte‐predominant Hodgkin lymphoma (NLPHL) is not well defined due to limited data. We report the first study on auto‐SCT for NLPHL with a larger cohort. Eligible for this retrospective registry study were patients reported to the EBMT between 2003 and 2013, aged 18 or older with relapsed/refractory NLPHL who underwent first auto‐SCT with disease chemosensitive to salvage therapy. NLPHL transformed to diffuse large B cell lymphoma were excluded. Sixty patients (83% male; median age 40 years) met the eligibility criteria. The median time between diagnosis and transplant was 21 months (IQR 13–58), and the median number of prior treatment lines was 2 (range 1–5), including rituximab in 63% of the patients. At auto‐SCT, 62% of the patients were in complete remission (CR) and 38% in partial remission. Seventy‐two percent of the patients received BEAM as high‐dose therapy. With a median follow‐up of 56 months (range 3–105), 5‐year progression‐free and overall survival (OS) were 66% and 87%, respectively. Univariate comparisons considering age, time from diagnosis to transplant, prior chemotherapy lines, and prior rituximab use failed to identify significant predictors for any survival endpoint except for being in CR at the time of auto‐SCT (vs PR, P = .049) for OS. Auto‐SCT in patients with relapsed/refractory NLPHL who are sensitive to salvage therapy gives excellent disease control and long‐term survival independent of the time interval between diagnosis and transplant.
One‐Step Reaction for Screening of Chromophores to Improve the Luminescence of Lanthanide Complexes
Authors: Dai Lixiong , Lo Wai‐Sum , Zhang Junhui , Law Ga‐Lai
Published: October 2017

A stable cyclen‐based EuIII‐complex precursor was synthesized in a one‐step coupling reaction as a fast‐screening tool and template to select suitable chromophores for sensitizing EuIII luminescence. A library of chromophores was synthesized and screened by either Sonogashira or Suzuki reaction to confirm the proof of concept and the ease of this methodology. The photophysical properties of these corresponding complexes as well as their potential properties for biological applications has been assessed.
Brief Report: Rituximab for the Treatment of Adult‐Onset IgA Vasculitis (Henoch‐Schönlein)
Authors: Maritati Federica , Fenoglio Roberta , Pillebout Evangeline , Emmi Giacomo , Urban Maria L. , Rocco Rossana , Nicastro Maria , Incerti Monia , Goldoni Matteo , Trivioli Giorgio , Silvestri Elena , Mohammad Aladdin J. , Jayne David , Eriksson Per , Segelmark Mårten , Novikov Pavel , Harris Helen , Roccatello Dario , Vaglio Augusto
Published: October 2017

Objective

Adult‐onset IgA vasculitis (Henoch‐Schönlein) (IgAV) is a rare systemic vasculitis characterized by IgA1‐dominant deposits. The treatment of adult‐onset IgAV is controversial and is based on the combination of glucocorticoids and immunosuppressive agents, but many patients have refractory or relapsing disease despite treatment. Rituximab (RTX) is a B cell–depleting antibody of proven efficacy in antineutrophil cytoplasmic antibody–associated vasculitis. We undertook this study to test the efficacy and safety of RTX in a multicenter cohort of patients with adult‐onset IgAV.

Methods

In this multicenter observational study, we included patients with adult‐onset IgAV who had received RTX either for refractory/relapsing disease or because they had contraindications to conventional glucocorticoid/immunosuppressive therapy. We analyzed the rates of remission (defined on the basis of the Birmingham Vasculitis Activity Score [BVAS]) and relapse as well as the variations over time in estimated glomerular filtration rate (GFR), proteinuria, C‐reactive protein (CRP) level, BVAS, and prednisone dose.

Results

Twenty‐two patients were included; their median duration of follow‐up was 24 months (interquartile range 18–48 months). Sixteen patients received RTX as add‐on therapy and 6 as monotherapy. Twenty patients (90.9%) achieved remission, and 7 of those 20 patients (35%) had subsequent relapse of disease. There were significant reductions in 24‐hour proteinuria (P < 0.0001), CRP level (P = 0.0005), BVAS (P < 0.0001), and prednisone dose (P < 0.0001) from RTX initiation through the last follow‐up visit; estimated GFR remained stable. RTX was generally well tolerated. One patient died after 60 months of follow‐up.

Conclusion

Our data suggest that RTX is an effective and safe therapeutic option for adult‐onset IgAV.
Progress in biopharmaceutical development
Authors: Kesik‐Brodacka Malgorzata
Published: October 2017

Since its introduction in 1982, biopharmaceutical drugs have revolutionized the treatment of a broad spectrum of diseases and are increasingly used in nearly all branches of medicine. In recent years, the biopharmaceuticals market has developed much faster than the market for all drugs and is believed to have great potential for further dynamic growth because of the tremendous demand for these drugs. Biobetters, which contain altered active pharmaceutical ingredients with enhanced efficacy, will play an important role in the development of biopharmaceuticals. Another significant group of biopharmaceuticals are biosimilars. Their introduction in the European Union and, recently, the Unites States markets will reduce the costs of biopharmaceutical treatment. This review highlights recent progress in the field of biopharmaceutical development and issues concerning the registration of innovative biopharmaceuticals and biosimilars. The leading class of biopharmaceuticals, the current biopharmaceuticals market, and forecasts are also discussed.
Identification of keratin 19‐positive cancer stem cells associating human hepatocellular carcinoma using CYFRA 21‐1
Authors: Kawai Takayuki , Yasuchika Kentaro , Ishii Takamichi , Katayama Hokahiro , Yoshitoshi Elena Yukie , Ogiso Satoshi , Minami Takahito , Miyauchi Yuya , Kojima Hidenobu , Yamaoka Ryoya , Kita Sadahiko , Yasuda Katsutaro , Sasaki Naoya , Fukumitsu Ken , Hatano Etsuro , Uemoto Shinji
Published: October 2017

The current lack of an easily measurable surrogate marker of cancer stem cells (CSCs) prevents the clinical application of CSCs for hepatocellular carcinoma (HCC). We previously reported that keratin 19 (K19) is a novel HCC‐CSC marker associated with transforming growth factor beta (TGFβ)/Smad signaling, and that K19+ HCC‐CSCs could be a new therapeutic target of TGFβ receptor 1 inhibitor LY2157299. In this study, we examined whether K19+ HCC‐CSCs can be tracked using cytokeratin 19 fragment CYFRA 21‐1. In 147 HCC patients who underwent curative resection and evaluated K19 expression by immunohistochemistry, preoperative serum CYFRA 21‐1 levels were significantly higher in K19+ patients than in K19− patients (P < 0.01). Receiver operating characteristic analyses revealed that serum CYFRA 21‐1 was the statistically significant and the most sensitive predictor of tumor K19 expression among preoperative laboratory test values (P < 0.001). In HCC cells encoding with a K19 promoter‐driven enhanced green fluorescent protein, fluorescence‐activated cell sorting (FACS)‐isolated K19+ cells displayed significantly higher levels of supernatant CYFRA 21‐1 than K19− cells (P < 0.01). Gain/loss of K19 function experiments confirmed that CYFRA 21‐1 levels were regulated by K19 function in HCC cells. Furthermore, CYFRA 21‐1 levels reflected the treatment efficacy of LY2157299 in K19+ cells. In conclusion, CYFRA 21‐1 can be used to predict K19 expression in HCC, and should thereby aid in the development of novel therapeutic strategies targeting K19+ HCC‐CSCs.
Assessing Capacity to Change in High‐Risk Pregnant Women: A Pilot Study
Authors: Harnett Paul H. , Barlow Jane , Coe Chris , Newbold Caroline , Dawe Sharon
Published: October 2017

Pre‐birth risk assessment is a process by which circumstances affecting an unborn child can be identified and support for mother and infant embedded. This mixed methods study describes a community‐based pre‐birth assessment and care pathway that utilised the Parents Under Pressure (PuP) programme to assess parenting capacity and provide support pre‐ and post‐birth for ‘at risk’ women. Sixty‐eight pregnant women referred to children's social care services were allocated to the pre‐birth assessment and care pathway (n = 35) or to routine care (n = 33). Standardised measures of psychological distress, social support and alcohol measured change for the women in the assessment and care pathway. Twenty women who provided pre‐ and post‐data reported significant improvements on all measures except alcohol use. Safeguarding outcomes at 12 months were obtained for both groups using administrative data. Forty‐two per cent of the infants whose mothers received the pre‐birth assessment and care pathway showed an improvement in child protection status compared to 14 per cent of the routine care infants. Safeguarding status deteriorated or stayed the same in 52 per cent of the routine cases compared to 26 per cent of those receiving the pathway. Qualitative data revealed that the pathway was acceptable and helpful to service users and service providers. Copyright © 2017 John Wiley & Sons, Ltd.

‘Describes a community‐based pre‐birth assessment and care pathway that utilised the Parents Under Pressure (PuP) programme’

Key Practitioner Messages

The current project found that a community‐based pre‐birth assessment and care pathway with high‐risk pregnant women was feasible and acceptable for practitioners and service users.

The pathway began mid‐pregnancy and support was provided following the birth of the infant for up to 12 months.

Over 40 per cent of infants whose mothers were allocated to the pre‐birth risk assessment pathway showed improvements in child safeguarding status at 12 months.
Mouse subthalamic nucleus neurons with local axon collaterals
Authors: Gouty‐Colomer Laurie‐Anne , Michel François J , Baude Agnès , Lopez‐Pauchet Catherine , Dufour Amandine , Cossart Rosa , Hammond Constance
Published: October 2017

The neuronal population of the subthalamic nucleus (STN) has the ability to prolong incoming cortical excitation. This could result from intra‐STN feedback excitation. The combination of inducible genetic fate mapping techniques with in vitro targeted patch‐clamp recordings, allowed identifying a new type of STN neurons that possess a highly collateralized intrinsic axon. The time window of birth dates was found to be narrow (E10.5–E14.5) with very few STN neurons born at E10.5 or E14.5. The fate mapped E11.5–12.5 STN neuronal population included 20% of neurons with profuse axonal branching inside the nucleus and a dendritic arbor that differed from that of STN neurons without local axon collaterals. They had intrinsic electrophysiological properties and in particular, the ability to generate plateau potentials, similar to that of STN neurons without local axon collaterals and more generally to that of classically described STN neurons. This suggests that a subpopulation of STN neurons forms a local glutamatergic network, which together with plateau potentials, allow amplification of hyperdirect cortical inputs and synchronization of the STN neuronal population.
Power Factor Control of Photovoltaic Generation Output for Improving Transient Stability
Authors: NOGAMI SHUN , YOKOYAMA AKIHIKO
Published: October 2017

Because of significant change in environmental policies and electric power deregulation in the last decades, a lot of photovoltaic (PV) generations have so far been installed to the power system in Japan. When a huge amount of PVs generation is installed into the power system, we are very much concerned that the disconnection of the PVs due to a system fault has a big impact on the power system stability and transient voltage stability. So it is important to equip the PV with Fault Ride Through (FRT) function in order to maintain power supply–demand balance. In addition, Dynamic Voltage Support (DVS) function of the PV is effective to recover the voltage after the system fault. However, it is unclear how the PVs which are equipped with the FRT and DVS functions affect transient stability and voltage stability. In this paper, how the power factor of the PV power output affects the power system after a system fault is analyzed using P–δ curve. Then, a new PV power factor control method for improving the transient stability is proposed and its effectiveness is shown by digital simulations on a simple power system model.
Weight Loss Trajectories in Bariatric Surgery Patients and Psychopathological Correlates
Authors: García‐Ruiz‐de‐Gordejuela Amador , Agüera Zaida , Granero Roser , Steward Trevor , Llerda‐Barberá Asunción , López‐Segura Elena , Vilarrasa Nuria , Sanchez Isabel , Jiménez‐Murcia Susana , Virgili Nuria , López‐Urdiales Rafael , de Bernabe Mónica Montserrat‐Gil , Garrido Pilar , Monseny Rosa , Monasterio Carmen , Salord Neus , Pujol‐Gebelli Jordi , Menchón Jose M. , Fernández‐Aranda Fernando
Published: October 2017

This study aimed to explore the empirical trajectories of body mass index (BMI) 1 year following bariatric surgery (BS) and to identify the risk factors for each trajectory. The study included 115 patients with severe obesity who underwent BS. Assessment included metabolic variables, psychopathological and personality measures. Growth mixture modelling identified four separated trajectories for the percentage of total weight loss course shape (namely, T1 ‘good‐fast’, T2 ‘good’, T3 ‘low’ and T4 ‘low‐slow’). After adjusting for BS subtype and metabolic baseline state, T1 and T2 registered less eating and general psychopathology. T1 was characterized by the lowest scores in novelty seeking and self‐transcendence, whereas T4 was defined by the highest scores in novelty seeking and the lowest scores in persistence. Our findings suggest that psychological state prior to BS is predictive of BMI trajectories during the 12 months following BS. These results could be useful in developing more efficient interventions for these patients. Copyright © 2017 John Wiley & Sons, Ltd and Eating Disorders Association.
Polydopamine‐collagen complex to enhance the biocompatibility of polydimethylsiloxane substrates for sustaining long‐term culture of L929 fibroblasts and tendon stem cells
Authors: Li Qian , Sun Lihong , Zhang Lei , Xu Zhigang , Kang Yuejun , Xue Peng
Published: October 2017

Polydimethylsiloxane (PDMS) is a commercialized polymer extensively used in the fabrication of versatile microfluidic microdevices for studies in cell biology and tissue engineering. However, the inherent surface hydrophobicity of PDMS is not optimal for cell culture and thus restrains its applications for investigation of long‐term behaviors of fibroblasts and stem cells. To improve the surface biocompatibility of PDMS, a facile technique was developed by modifying the PDMS surface with polydopamine‐collagen (COL/PDA) complex. The successful synthesis of COL/PDA was verified through proton nuclear magnetic resonance spectroscopy. Compared to surface coating solely with COL or PDA, the surface wettability was significantly improved on COL/PDA‐modified PDMS substrates based on water contact angle characterizations. The modified PDMS surface remarkably enhanced the initial adhesion and long‐term proliferation of L929 fibroblasts and tendon stem cells (TSCs). Additionally, the effects of COL/PDA coating on cell viability and apoptosis were further investigated under prolonged incubation. We found that the COL/PDA coating on PDMS resulted in a substantial increase of cell viability compared to native PDMS, and the cell apoptosis was considerably impeded on the modified PDMS. This study demonstrated that COL/PDA coating can effectively enhance the surface biocompatibility of PDMS as verified by the enhanced adhesion and long‐term proliferation of L929 fibroblasts and TSCs. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 408–418, 2018.
Osseous response on linear and cyclic RGD‐peptides immobilized on titanium surfacesin vitroandin vivo
Authors: Heller M. , Kumar V. V. , Pabst A. , Brieger J. , Al‐Nawas B. , Kämmerer P. W.
Published: October 2017

Biomimetic surface modifications of titanium (Ti) implants using the Arg‐Gly‐Asp‐sequence (RGD) are promising to accelerate bone healing in cases of medical implants. Therefore, we compared the impact of linear and cyclic RGD (l‐ and c‐RGD) covalently coupled onto Ti surfaces on the osseous responsein vitroandin vivo.In vitro, osteoblasts’ behavior on different surfaces (unmodified, amino‐silanized [APTES], l‐ and c‐RGD) was analysed regarding adhesion (fluorescence microscopy), proliferation (resazurin stain) and differentiation (reverse transcription polymerase chain reaction on alkaline phosphatase and osteocalcin).In vivo, osteosynthesis screws (unmodifiedn = 8, l‐RGDn = 8, c‐RGDn = 8) were inserted into the proximal tibiae of 12 rabbits and evaluated for bone growth parameters (bone implant contact [%] and vertical bone apposition [VBA;%]) at 3 and 6 weeks.In vitro, c‐ as well as l‐RGD surfaces stimulated osteoblasts’ adherence, proliferation and differentiation in a similar manner, with only subtle evidence of superiority of the c‐RGD modifications.In vivo, c‐RGD‐modifications led to a significantly increased VBA after 3 and 6 weeks. Thus, coating with c‐RGD appears to play an important role influencing osteoblasts’ behaviourin vitrobut especiallyin vivo. These findings can be applied prospectively to implantable biomaterials with hypothetically improved survival and success rates. © 2017 Wiley Periodicals Inc. J Biomed Mater Res Part A: 106A: 419–427, 2018.
Hydrogenolysis of glycerol to 1,2‐propanediol in a continuous flow trickle bed reactor
Authors: Manuale Debora L , Santiago Lucía V , Torres Gerardo C , Sepúlveda Jorge H , Torresi Pablo A , Vera Carlos R , Yori Juan C
Published: October 2017

BACKGROUND

Hydrogenolysis of glycerol to glycols in continuous flow three phase reactors is of practical importance due to the need to give value to huge amounts of surplus glycerol. Thermodynamic and kinetic aspects must be revised for a proper design. The system was studied in a trickle‐bed reactor using copper chromite and Cu/Al2O3as catalysts.

RESULTS

Phase equilibrium and flow pattern were verified. Solid, liquid and gas phases were present, with the liquid phase in ‘trickling’ flow. Catalysts were characterized by inductively coupled plasma (ICP), nitrogen sortometry, X‐ray photoelectron spectroscopy (XPS), X‐ray diffraction (XRD), temperature programmed reduction (TPR) and pyridine thermal programmed desorption (TPD). The average reaction rate was found to be practically constant under different process conditions. A theoretical analysis indicated that the resistance to the transfer of hydrogen from the gas to the liquid phase dominated the overall kinetics. Selectivity to 1,2‐propanediol varied with temperature, with a maximum at 230 °C (97%). Selectivity was a function of the catalyst acidity. When the pressure was increased the selectivity to 1,2‐propanediol was increased, up to 97% at 14 bar. Higher pressures did not modify this value.

CONCLUSIONS

Optimum reaction conditions for maximum selectivity to 1,2‐propanediol with Cu‐based catalysts are 230 °C and 14 bar. System kinetics are, however, dominated by the gas–liquid mass transfer resistance. © 2017 Society of Chemical Industry
Serum proteomic assessment of the progression of fracture healing
Authors: Hussein Amira I. , Mancini Christian , Lybrand Kyle E. , Cooke Margaret E. , Matheny Heather E. , Hogue Brenna L. , Tornetta Paul , Gerstenfeld Louis C.
Published: October 2017

A targeted proteomic analysis of murine serum over a 35‐day course of fracture healing was carried out to determine if serum proteomic changes could be used to monitor the biological progression of fracture healing. Transverse, closed femoral fractures where generated and stabilized with intramedullary fixation. A single stranded DNA aptamer‐based multiplexed proteomic approach was used to assay 1,310 proteins. The transcriptomic profiles for genes matching the 1,310 proteins were obtained by microarray analysis of callus mRNA. Of the 1,310 proteins analyzed, 850 proteins showed significant differences among the time points (p‐value <0.05). Ontology assessment associated these proteins with osteoblasts, monocyte/macrophage lineages, mesenchymal stem cell lines, hepatic tissues, and lymphocytes. Temporal clustering of these data identified proteins associated with inflammation, cartilage formation and bone remodeling stages of healing. VEGF, Wnt, and TGF‐βsignaling pathways were restricted to the period of cartilage formation. Comparison of the proteomic and transcriptomic profiles showed that 87.5% of proteins in serum had concordant expression to their mRNA expression in the callus, while 12.5% of the protein and mRNA expression patterns were discordant. The discordant proteins that were elevated in the serum but down regulated in callus mRNA expression were related to clotting functions, allograft rejection, and complement function. While proteins down regulated in the serum and elevated in callus mRNA were associated with osteoblast function, NF‐ĸb, and activin signaling. These data show the serum proteome may be used to monitor the different biological stages of fracture healing and have translational potential in assessing human fracture healing. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1153–1163, 2018.
Systematic review of lymphovenous anastomosis (LVA) for the treatment of lymphedema
Authors: Scaglioni Mario F. , Fontein Duveken B. Y. , Arvanitakis Michael , Giovanoli Pietro
Published: October 2017

Introduction

Lymphedema is a chronic condition caused by the obstruction or impairment of lymphatic fluid transport resulting in irreversible skin fibrosis. Besides conservative therapy, surgical techniques for lymphedema including liposuction, lymphatico‐lymphatic bypass, lymphovenous anastomosis (LVA), and vascularized lymph node transfer (VLNT) are options with increasing popularity in the recent past. In our review, we investigated the efficacy of LVA for the treatment of lymphedema. Both objective and subjective outcomes of surgical treatment were evaluated.

Methods

Studies were identified through systematic review in PubMed database up to September 2016. Only original Articles which exclusively performed LVA for lymphedema treatment were included. Our primary endpoint was the objective of a subjective postoperative lymphedema reduction.

Results

A total of 293 titles were identified, out of which 18 studies including 939 patients were deemed eligible. The studies included in this review describe significant variations in surgical techniques, number of anastomoses and supplementary interventions. All studies reported objective reductions in circumference measurements. Subjective symptom relief was found in 50‐100% of the patients as well as a reduction in the number of cellulitis episodes in all investigated cases.

Conclusion

Although the studies included in this review showed great heterogeneity, LVA surgery revealed both objective and subjective improvements in most patients.
Reduced acoustic noise in diffusion tensor imaging on a compact MRI system
Authors: Tan Ek T. , Hardy Christopher J. , Shu Yunhong , In Myung‐Ho , Guidon Arnaud , Huston John , Bernstein Matt A. , K.F. Foo Thomas
Published: October 2017

Purpose

To investigate the feasibility of substantially reducing acoustic noise while performing diffusion tensor imaging (DTI) on a compact 3T (C3T) MRI scanner equipped with a 42‐cm inner‐diameter asymmetric gradient.

Methods

A‐weighted acoustic measurements were made using 10 mT/m‐amplitude sinusoidal waveforms, corresponding to echo‐planar imaging (EPI) echo spacing of 0.25 to 5.0 ms, on a conventional, whole‐body 3T MRI and on the C3T. Acoustic measurements of DTI with trapezoidal EPI waveforms were then made at peak gradient performance on the C3T (80 mT/m amplitude, 700 T/m/s slew rate) and at derated performance (33 mT/m, 10 to 50 T/m/s) for acoustic noise reduction. DTI was acquired in two different phantoms and in seven human subjects, with and without gradient‐derating corresponding to multi‐ and single‐shot acquisitions, respectively.

Results

Sinusoidal waveforms on the C3T were quieter by 8.5 to 15.6 A‐weighted decibels (dBA) on average as compared to the whole‐body MRI. The derated multishot DTI acquisition noise level was only 8.7 dBA (at 13 T/m/s slew rate) above ambient, and was quieter than non‐derated, single‐shot DTI by 22.3 dBA; however, the scan time was almost quadrupled. Although derating resulted in negligible diffusivity differences in the phantoms, small biases in diffusivity measurements were observed in human subjects (apparent diffusion coefficient = +9.3 ± 8.8%, fractional anisotropy = +3.2 ± 11.2%, radial diffusivity = +9.4 ± 16.8%, parallel diffusivity = +10.3 ± 8.4%).

Conclusion

The feasibility of achieving reduced acoustic noise levels with whole‐brain DTI on the C3T MRI was demonstrated. Magn Reson Med 79:2902–2911, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
Sonography‐guided recording for superficial peroneal sensory nerve conduction study
Authors: Kim Ki Hoon , Park Byung Kyu , Kim Dong Hwee , Kim Yuntae
Published: October 2017

Introduction

We sought to establish the optimal recording position for antidromic conduction of the superficial peroneal nerve (SPN) by using ultrasonography (USG).

Methods

The sensory nerve action potentials (SNAPs) of the intermediate dorsal cutaneous nerve (IDCN) and medial dorsal cutaneous nerve (MDCN) in 64 limbs of 32 healthy participants were recorded (nerve conduction study [NCS]‐1). Both nerves were identified by using USG, and the SNAPs were obtained from the USG‐guided repositioned electrodes (NCS‐2).

Results

The IDCN and MDCN were located at 29.3% ± 5.1% and 43.9% ± 4.9% of the intermalleolar distance from the lateral malleolus, respectively. Significantly greater amplitude was shown for SNAPs of both nerves in NCS‐2 versus NCS‐1.

Discussion

The optimal recording position is likely to be lateral, one‐third from the lateral malleolus for the IDCN, and just lateral to the midpoint of the intermalleolar line for the MDCN. When the SPN response is unexpectedly attenuated, USG‐guided repositioning of the electrodes should be considered. Muscle Nerve 57: 628–633, 2018
Orthogonal spline collocation scheme for multiterm fractional convection‐diffusion equation with variable coefficients
Authors: Yang Xuehua , Zhang Haixiang , Xu Da
Published: October 2017

The orthogonal spline collocation (OSC) technique is an efficient way to solve a wide variety of problems that are modeled by ordinary and partial differential equations. In this article, by using OSC method in spatial direction and classical L1 approximation in temporal direction, a fully discrete scheme is established for a class of two‐dimensional multiterm fractional convection‐diffusion reaction equation with variable coefficients. The optimal estimates in Hj (j = 0, 1, 2) norms at each time step are derived. Also, estimate in space is provided. At last, we provide some numerical results to verify the accuracy and efficiency of the proposed algorithm.
Effects of process parameters on thermal properties of glass fiber reinforced polyamide 6 composites throughout the direct long‐fiber‐reinforced thermoplastics process
Authors: Whitfield Thomas , Kuboki Takashi , Wood Jeffrey , Ugresic Vanja , Sathyanarayana Shyam , Dagnon Koffi
Published: October 2017

The direct long‐fiber‐reinforced thermoplastic (D‐LFT) process is an efficient, one‐stop manufacturing process starting from raw materials to a final product, and includes various types of equipment. Tandem twin‐screw extruders are the main components of the D‐LFT process, and their control dictates productivity and properties of products. This study investigates the effects of extruder temperature and screw speed on molecular weight and thermal properties of glass fiber‐reinforced polyamide 6 (PA6) composites throughout the D‐LFT process. Viscosity number measurements, thermogravimetric analyses (TGA), and differential scanning calorimetry (DSC) analyses were performed on samples taken from different locations along the D‐LFT process. It was found that viscosity number, which is a measure of molecular weight of the PA6 base resin, decreased with increasing extruder temperature and decreasing screw speed. In contrast, TGA results showed that the low screw speed of the extruders increased apparent activation energy of the final product. Non‐isothermal DSC crystallization analysis revealed no substantial changes to the material's degree of crystallinity with the variations in extruder temperature and screw speed; however, isothermal DSC crystallization analysis showed that the low screw speed of the extruders increased crystallization half‐time of the final material. POLYM. ENG. SCI., 58:E114–E123, 2018. © 2017 Society of Plastics Engineers
Exercise induced effects on muscle function and range of motion in patients with hip osteoarthritis
Authors: Bieler Theresa , Siersma Volkert , Magnusson S. Peter , Kjaer Michael , Beyer Nina
Published: October 2017

Background and purpose

Patients with hip osteoarthritis have impairments in muscle function (muscle strength and power) and hip range of motion (ROM), and it is commonly believed that effective clinical management of osteoarthritis should address these impairments to reduce pain and disability. Therefore, the purpose of this study was to compare the short‐ and long‐term effects of 4 months of physiotherapist‐supervised strength training, physiotherapist‐supervised Nordic Walking (NW), or unsupervised home‐based exercise (HBE) on muscle function and hip ROM in patients diagnosed with hip osteoarthritis.

Methods

Secondary outcome analyses from an observer‐blinded three‐armed parallel‐design randomized controlled trial in 60+‐year‐old patients with clinical hip osteoarthritis (American College of Rheumatology criteria) who were not on a waiting list for hip replacement. One hundred and fifty‐two patients were randomized to either 4 months of physiotherapist‐supervised, moderate, progressive, strength training (n = 50), physiotherapist‐supervised NW (n = 50), or unsupervised HBE (n = 52). Maximal isometric hip and thigh muscle strength and leg extensor power and active hip ROM were assessed at baseline 2, 4, and 12 months.

Results

Intention‐to‐treat‐analyses did not show any significant between‐group differences for improvements in muscle strength and power or ROM at any time points. Short‐term significant (p < .05) increases in muscle strength were present in the physiotherapist‐supervised exercise groups and in the long‐term for muscle power in the NW‐group. All exercise modes resulted in significant increases of ROM but long‐term improvements were only shown for NW and HBE.

Discussion

Four months of physiotherapist‐supervised, progressive, moderate, and strength training was less effective than hypothesized for improving muscle strength and power in patients with hip osteoarthritis who are not awaiting hip replacement. Our results may indicate that in these patients, improvements in disability are not necessarily dependent on improvements in strength and power or ROM.
Residential segregation and the fertility of immigrants and their descendants
Authors: Wilson Ben , Kuha Jouni
Published: October 2017

Measures of community population composition, such as residential segregation, are important theoretical mechanisms that have the potential to explain differences in fertility between immigrants, their descendants, and destination natives. However, only a handful of studies explore these mechanisms, and most are limited by the fact that they carry out cross‐sectional analysis. This study proposes a new approach, which focuses on community composition in childhood. It uses longitudinal census data and registered births in England and Wales to investigate the relationship between completed fertility and multiple measures of community composition, including residential segregation. The results show that the fertility of immigrants is closer to native fertility if they grow up in less segregated areas. This provides evidence in support of the childhood socialisation hypothesis. Furthermore, residential segregation explains some of the variation in completed fertility for second‐generation women from Pakistan and Bangladesh, the only second‐generation group to have significantly higher completed fertility than natives. This suggests one reason why the fertility of some South Asians in England and Wales may remain “culturally entrenched.” All of these findings are consistent for different measures of community composition. They are also easier to interpret than the results of previous research because exposure is measured before childbearing has commenced, therefore avoiding many issues relating to selection, simultaneity, and conditioning on the future.
Negative affective stress reactivity: The dampening effect of snacking
Authors: Wouters Saskia , Jacobs Nele , Duif Mira , Lechner Lilian , Thewissen Viviane
Published: October 2017

The present study sets out to further elucidate the complex relationship between daily hassles, snacking, and negative affect (NA). The aim of the present study was to examine whether or not moment‐to‐moment energy intake from snacks moderates the association between momentary stress and NA. And, if so, can this moderating effect be replicated by using the amount of macronutrient intake (i.e., carbohydrates, fat, and protein) as moderator on the association between momentary stress and NA? Adults (N = 269), aged 20–50 years, participated in this study. Stress, NA, and snack intake were assessed 10 times a day for 7 consecutive days in daily life with an experience sampling smartphone application. Multilevel regression analyses were performed to assess the hypothesized associations. Our study revealed a dampening effect of snacking on negative affective stress reactivity. However, this dampening effect could not be replicated by the amount of macronutrient intake from snacks. On the contrary, the amount of carbohydrates has an enhancing effect on negative affective stress reactivity. In the end, our study suggests that the critical question is which mechanisms are decisive in the dampening role of snacking on stress reactivity. A multidisciplinary approach may provide a full perspective.