bluuebunny/crossref_metadata_2025 huggingface dataset:
Esthesioneuroblastoma with intracranial extension: A non-surgical approach
Authors: Thomas Sarah , Balasubramaniam Deepak , Hiran K , Dinesh M , Pavithran K
Published: November 2014

Esthesioneuroblastoma is a rare tumor arising from the olfactory mucosa of upper respiratory tract. The primary modality of treatment has been surgery with craniofacial resection followed by post-operative radiotherapy. There are only a few reported cases of non-surgical approaches. We report a case of esthesioneuroblastoma with intracranial extension treated with Vincristine, Adriamycin, Cyclophosphamide, Ifosfamide, Etoposide protocol followed by radiation with 5 years of follow-up. This is the first reported case using this chemotherapy schedule.
Primary non-Hodgkin's lymphoma of the skull with extra and intracranial extension presenting with bulky scalp mass lesion
Authors: Jaiswal Manish , Gandhi Ashok , Purohit Devendra , Singhvi Shashi , Mittal Radhey
Published: November 2014

Primary non-Hodgkin's lymphoma (NHL) of the cranium with extra- and intracranial extension without systemic or skeletal manifestation in a non-immunocompromised patient is extremely rare. These lesions are most of the time misdiagnosed because they mimic other conditions like meningioma. Here, we report a case presented with huge bulky scalp mass which on magnetic resonance imaging (MRI) brain showed involvement of scalp, cranial vault, meninges, and the brain parenchyma, mimicking a meningioma. After gross total resection, biopsy and CD marker study revealed primary non-Hodgkin's diffuse large B-cell lymphoma (DLBCL). Malignant NHL should be considered in differential diagnosis of bulky scalp mass lesion.
Chronic subdural hematoma
Authors: Yadav Yad , Parihar Vijay , Namdev Hemant , Bajaj Jitin
Published: November 2014

Chronic subdural hematoma (CSDH) is one of the most common neurosurgical conditions. There is lack of uniformity in the treatment of CSDH amongst surgeons in terms of various treatment strategies. Clinical presentation may vary from no symptoms to unconsciousness. CSDH is usually diagnosed by contrast-enhanced computed tomography scan. Magnetic resonance imaging (MRI) scan is more sensitive in the diagnosis of bilateral isodense CSDH, multiple loculations, intrahematoma membranes, fresh bleeding, hemolysis, and the size of capsule. Contrast-enhanced CT or MRI could detect associated primary or metastatic dural diseases. Although definite history of trauma could be obtained in a majority of cases, some cases may be secondary to coagulation defect, intracranial hypotension, use of anticoagulants and antiplatelet drugs, etc., Recurrent bleeding, increased exudates from outer membrane, and cerebrospinal fluid entrapment have been implicated in the enlargement of CSDH. Burr-hole evacuation is the treatment of choice for an uncomplicated CSDH. Most of the recent trials favor the use of drain to reduce recurrence rate. Craniotomy and twist drill craniostomy also play a role in the management. Dural biopsy should be taken, especially in recurrence and thick outer membrane. Nonsurgical management is reserved for asymptomatic or high operative risk patients. The steroids and angiotensin converting enzyme inhibitors may also play a role in the management. Single management strategy is not appropriate for all the cases of CSDH. Better understanding of the nature of the pathology, rational selection of an ideal treatment strategy for an individual patient, and identification of the merits and limitations of different surgical techniques could help in improving the prognosis.
The Process of Installing REDCap, a Web Based Database Supporting Biomedical Research
Authors: Mare I. , Hazelhurst S. , Kramer B. , Klipin M.
Published: November 2014

Background: Clinical and research data are essential for patient care, research and healthcare system planning. REDCapTM is a web-based tool for research data curatorship developed at Vanderbilt University in Nashville, USA. The Faculty of Health Sciences at the University of the Witwatersrand, Johannesburg South Africa identified the need for a cost effective data management instrument. REDCap was installed as per the user agreement with Vanderbilt University in August 2012.

Objectives: In order to assist other institutions that may lack the in-house Information Technology capacity, this paper describes the installation and support of REDCap and incorporates an analysis of user uptake over the first year of use.

Methods: We reviewed the staffing requirements, costs of installation, process of installation and necessary infrastructure and end-user requests following the introduction of REDCap at Wits. The University Legal Office and Human Research Ethics Committee were consulted regarding the REDCap end-user agreement. Bi-monthly user meetings resulted in a training workshop in August 2013. We compared our REDCap software user numbers and records before and after the first training workshop.

Results: Human resources were recruited from existing staff. Installation costs were limited to servers and security certificates. The total costs to provide a functional REDCap platform was less than $9000. Eighty-one (81) users were registered in the first year. After the first training workshop the user numbers increased by 59 in one month and the total number of active users to 140 by the end of August 2013. Custom software applications for REDCap were created by collaboration between clinicians and software developers.

Conclusion: REDCap was installed and maintained at limited cost. A small number of people with defined skills can support multiple REDCap users in two to four hours a week. End user training increased in the number of users, number of projects created and the number of projects moved to production.

Citation: Klipin M, Mare I, Hazelhurst S, Kramer B. The process of installing REDCap, a web based database supporting biomedical research – the first year. Appl Clin Inf 2014; 5: 916–929

http://dx.doi.org/10.4338/ACI-2014-06-CR-0054
Aerosol indirect effects on continental low-level clouds over Sweden and Finland
Authors: Sporre M. K. , Swietlicki E. , Glantz P. , Kulmala M.
Published: November 2014

Abstract. Aerosol effects on low-level clouds over the Nordic Countries are investigated by combining in situ ground-based aerosol measurements with remote sensing data of clouds and precipitation. Ten years of number size distribution data from two aerosol measurement stations (Vavihill, Sweden and Hyytiälä, Finland) provide aerosol number concentrations in the atmospheric boundary layer. This is combined with cloud satellite data from the Moderate Resolution Imaging Spectroradiometer and weather radar data from the Baltic Sea Experiment. Also, how the meteorological conditions affect the clouds is investigated using reanalysis data from the European Centre for Medium-Range Weather Forecasts. The cloud droplet effective radius is found to decrease when the aerosol number concentration increases, while the cloud optical thickness does not vary with boundary layer aerosol number concentrations. Furthermore, the aerosol–cloud interaction parameter (ACI), a measure of how the effective radius is influenced by the number concentration of cloud active particles, is found to be somewhere between 0.10 and 0.18 and the magnitude of the ACI is greatest when the number concentration of particles with a diameter larger than 130 nm is used. Lower precipitation intensity in the weather radar images is associated with higher aerosol number concentrations. In addition, at Hyytiälä the particle number concentrations is generally higher for non-precipitating cases than for precipitating cases. The apparent absence of the first indirect effect of aerosols on low-level clouds over land raises questions regarding the magnitude of the indirect aerosol radiative forcing.
Quantifying the value of redundant measurements at GCOS Reference Upper-Air Network sites
Authors: Madonna F. , Rosoldi M. , Güldner J. , Haefele A. , Kivi R. , Cadeddu M. P. , Sisterson D. , Pappalardo G.
Published: November 2014

Abstract. The potential for measurement redundancy to reduce uncertainty in atmospheric variables has not been investigated comprehensively for climate observations. We evaluated the usefulness of entropy and mutual correlation concepts, as defined in information theory, for quantifying random uncertainty and redundancy in time series of the integrated water vapour (IWV) and water vapour mixing ratio profiles provided by five highly instrumented GRUAN (GCOS, Global Climate Observing System, Reference Upper-Air Network) stations in 2010–2012. Results show that the random uncertainties on the IWV measured with radiosondes, global positioning system, microwave and infrared radiometers, and Raman lidar measurements differed by less than 8%. Comparisons of time series of IWV content from ground-based remote sensing instruments with in situ soundings showed that microwave radiometers have the highest redundancy with the IWV time series measured by radiosondes and therefore the highest potential to reduce the random uncertainty of the radiosondes time series. Moreover, the random uncertainty of a time series from one instrument can be reduced by ~ 60% by constraining the measurements with those from another instrument. The best reduction of random uncertainty is achieved by conditioning Raman lidar measurements with microwave radiometer measurements. Specific instruments are recommended for atmospheric water vapour measurements at GRUAN sites. This approach can be applied to the study of redundant measurements for other climate variables.
Effect of ions on the measurement of sulfuric acid in the CLOUD experiment at CERN
Authors: Rondo L. , Kürten A. , Ehrhart S. , Schobesberger S. , Franchin A. , Junninen H. , Petäjä T. , Sipilä M. , Worsnop D. R. , Curtius J.
Published: November 2014

Abstract. Ternary aerosol nucleation experiments were conducted in the CLOUD chamber at CERN in order to investigate the influence of ions on new particle formation. Neutral and ion-induced nucleation experiments, i.e. without and with the presence of ions, respectively, were carried out under precisely controlled conditions. The sulfuric acid concentration was measured with a chemical ionisation mass spectrometer (CIMS) during the new particle formation experiments. The added ternary trace gases were ammonia (NH3), dimethylamine (DMA, C2H7N) or oxidised products of pinanediol (PD, C10H18O2). When pinanediol was introduced into the chamber, an increase in the mass spectrometric signal used to determine the sulfuric acid concentration (m/z 97, i.e. HSO4−) was observed due to ions from the CLOUD chamber. The enhancement was only observed during ion-induced nucleation measurements by using either galactic cosmic rays (GCRs) or the proton synchrotron (PS) pion beam for the ion generation, respectively. The ion effect typically involved an increase in the apparent sulfuric acid concentration by a factor of ~ 2 to 3 and was qualitatively verified by the ion measurements with an atmospheric-pressure interface-time of flight (APi-TOF) mass spectrometer. By applying a high-voltage (HV) clearing field inside the CLOUD chamber, the ion effect on the CIMS measurement was completely eliminated since, under these conditions, small ions are swept from the chamber in about 1 s. In order to exclude the ion effect and to provide corrected sulfuric acid concentrations during the GCR and PS beam nucleation experiments, a parameterisation was derived that utilises the trace gas concentrations and the UV light intensity as input parameters. Atmospheric sulfuric acid measurements with a CIMS showed an insignificant ion effect.
Reconstruction of 3-D cloud geometry using a scanning cloud radar
Authors: Ewald F. , Winkler C. , Zinner T.
Published: November 2014

Abstract. Clouds are one of the main reasons of uncertainties in the forecasts of weather and climate. In part, this is due to limitations of remote sensing of cloud microphysics. Present approaches often use passive spectral measurements for the remote sensing of cloud microphysical parameters. Large uncertainties are introduced by three dimensional (3-D) radiative transfer effects and cloud inhomogeneities. Such effects are largely caused by unknown orientation of cloud sides or by shadowed areas on the cloud. Passive ground based remote sensing of cloud properties at high spatial resolution could be improved crucially with this kind of additional knowledge of cloud geometry. To this end, a method for the accurate reconstruction of 3-D cloud geometry from cloud radar measurements is developed in this work. Using a radar simulator and simulated passive measurements of static LES model clouds, the effects of different radar scan resolutions and varying interpolation methods are evaluated. In reality a trade-off between scan resolution and scan duration has to be found as clouds are changing quickly. A reasonable choice is a scan resolution of 1 to 2°. The most suitable interpolation procedure identified is the barycentric interpolation method. The 3-D reconstruction method is demonstrated using radar scans of convective cloud cases with the Munich miraMACS, a 35 GHz scanning cloud radar. As a successful proof of concept, camera imagery collected at the radar location is reproduced for the observed cloud cases via 3-D volume reconstruction and 3-D radiative transfer simulation. Data sets provided by the presented reconstruction method will aid passive spectral ground-based measurements of cloud sides to retrieve microphysical parameters.
Deterministic prediction of surface wind speed variations
Authors: Drisya G. V. , Kiplangat D. C. , Asokan K. , Satheesh Kumar K.
Published: November 2014

Abstract. Accurate prediction of wind speed is an important aspect of various tasks related to wind energy management such as wind turbine predictive control and wind power scheduling. The most typical characteristic of wind speed data is its persistent temporal variations. Most of the techniques reported in the literature for prediction of wind speed and power are based on statistical methods or probabilistic distribution of wind speed data. In this paper we demonstrate that deterministic forecasting methods can make accurate short-term predictions of wind speed using past data, at locations where the wind dynamics exhibit chaotic behaviour. The predictions are remarkably accurate up to 1 h with a normalised RMSE (root mean square error) of less than 0.02 and reasonably accurate up to 3 h with an error of less than 0.06. Repeated application of these methods at 234 different geographical locations for predicting wind speeds at 30-day intervals for 3 years reveals that the accuracy of prediction is more or less the same across all locations and time periods. Comparison of the results with f-ARIMA model predictions shows that the deterministic models with suitable parameters are capable of returning improved prediction accuracy and capturing the dynamical variations of the actual time series more faithfully. These methods are simple and computationally efficient and require only records of past data for making short-term wind speed forecasts within practically tolerable margin of errors.
Multi-isotope labelling (13C, 18O, 2H) of fresh assimilates to trace organic matter dynamics in the plant-soil system
Authors: Studer M. S. , Siegwolf R. T. W. , Leuenberger M. , Abiven S.
Published: November 2014

Abstract. Isotope labelling is a powerful tool to study elemental cycling within terrestrial ecosystems. Here we describe a new multi-isotope technique to label organic matter (OM). We exposed poplars (Populus deltoides x nigra) for 14 days to an atmosphere enriched in 13CO2 and depleted in 2H218O. After one week, the water-soluble leaf OM (δ13C = 1346 ± 162‰) and the leaf water were strongly labelled (δ18O = −63± 8‰, δ2H = −156 ± 15‰). The leaf water isotopic composition was between the atmospheric and stem water, indicating a considerable diffusion of vapour into the leaves (58–69%). The atomic ratios of the labels recovered (18O/13C, 2H/13C) were 2–4 times higher in leaves than in the stems and roots. This either indicates the synthesis of more condensed compounds (lignin vs. cellulose) in roots and stems, or be the result of O and H exchange and fractionation processes during transport and biosynthesis. We demonstrate that the three major OM elements (C, O, H) can be labelled and traced simultaneously within the plant. This approach could be of interdisciplinary interest for the fields of plant physiology, paleoclimatic reconstruction or soil science.
Hydroclimate variability of the northwestern Amazon Basin near the Andean foothills of Peru related to the South American Monsoon System during the last 1600 years
Authors: Apaéstegui J. , Cruz F. W. , Sifeddine A. , Vuille M. , Espinoza J. C. , Guyot J. L. , Khodri M. , Strikis N. , Santos R. V. , Cheng H. , Edwards L. , Carvalho E. , Santini W.
Published: November 2014

Abstract. In this paper we explore a speleothem δ18O record from Palestina cave, northwestern Peru, at a site on the eastern side of the Andes cordillera, in the upper Amazon Basin. The δ18O record is interpreted as a proxy for South American Summer Monsoon (SASM) intensity and allows the reconstruction of its variability during the last 1600 years. Two periods of anomalous changes in the climate mean state corresponding to the Medieval Climate Anomaly (MCA) and the Little Ice Age (LIA) periods identified in the Northern Hemisphere are recognized in the record, in which decreased and increased SASM activity, respectively, have been documented. Variations in SASM activity between the MCA and the LIA seem to be larger over the northern part of the continent, suggesting a latitudinal dependence of the MCA footprint. Our results, based on time series, composite and wavelet analyses, suggest that the Atlantic Multidecadal Oscillation (AMO) plays an relevant role for SASM modulation on multidecadal scales (∼65 years), especially during dry periods such as the MCA. Composite analyses, applied to evaluate the influence of the AMO on the Palestina cave δ18O and other δ18O-derived SASM reconstructions, allow insight into the spatial footprints of the AMO over tropical South America and highlight differences between records during key studied periods. This work also reveals that replicating regional climate signals from different sites, and using different proxies is absolutely essential for a comprehensive understanding of past changes in SASM activity.
A simulation model to assess groundwater recharge over Europe's karst regions
Authors: Hartmann A. , Gleeson T. , Rosolem R. , Pianosi F. , Wada Y. , Wagener T.
Published: November 2014

Abstract. Karst develops through the dissolution of carbonate rock and is a major source of groundwater contributing up to half of the total drinking water supply in some European countries. Previous approaches to model future water availability in Europe are either too-small scale or do not incorporate karst processes, i.e. preferential flow paths. This study presents the first simulations of groundwater recharge in all karst regions in Europe with a parsimonious karst hydrology model. A novel parameter confinement strategy combines a priori information with recharge-related observations (actual evapotranspiration and soil moisture) at locations across Europe while explicitly identifying uncertainty in the model parameters. Europe's karst regions are divided into 4 typical karst landscapes (humid, mountain, Mediterranean and desert) by cluster analysis and recharge is simulated from 2002 to 2012 for each karst landscape. Mean annual recharge ranges from negligible in deserts to > 1 m a−1 in humid regions. The majority of recharge rates ranges from 20–50% of precipitation and are sensitive to sub-annual climate variability. Simulation results are consistent with independent observations of mean annual recharge and significantly better than other global hydrology models that do not consider karst processes (PCR-GLOBWB, WaterGAP). Global hydrology models systematically underestimate karst recharge implying that they over-estimate actual evapotranspiration and surface runoff. Karst water budgets and thus information to support management decisions regarding drinking water supply and flood risk are significantly improved by our model.
Reliability of the six-minute walk test after total hip arthroplasty
Authors: Unver Bayram , Kahraman Turhan , Kalkan Serpil , Yuksel Ertuğrul , Karatosun Vasfi
Published: November 2014

Background

Walking ability is a crucial component of lower extremity function. Assessment of walking after total hip arthroplasty (THA) provides important information about the healing process. Walking endurance, an important functional component of walking, can be reliably measured with the 6-minute walk test (6 mWT). Even though the 6 mWT is commonly used in patients with THA, its reliability has never been reported for this patient population. The aim of this study is to assess the reliability of the test-retest 6 mWT after THA.

Methods

Thirty-four patients with THA performed two test trials on the same day, separated by a one hour seated rest. To assess reliability, intra-class correlation coefficient (ICC2,1 ), standard error of measurement (SEM), and smallest real difference (SRD) were calculated.

Results

The 6 mWT showed a high reliability. The patients walked 3.71 metres more at the end of the second 6 mWT in comparison with the first test. The ICC2,1 (AS95 ), SEM (m), SEM95 (m) and SRD95 (m) were 0.96 (0.92), 3.67, 7.19, and 10.17 m respectively.

Conclusions

Reliability of the 6 mWT was high in patients with THA. The 6 mWT is a simple and sensitive method to measure the functional performance in patients with THA in the clinical setting. Moreover, clinicians and researchers can use the 6 mWT to quantify even small changes in functional performance after THA.
The Predictive Value of Radiostereometric Analysis for Stem Survival in Total Hip Arthroplasty. A Systematic Review
Authors: de Vries Lieke M.A. , van der Weegen Walter , Pilot Peter , Stolarczyk Piotr A. , Sijbesma Thea , Hoffman Erik L.
Published: November 2014

Background

The high precision of radiostereometric analysis (RSA) has enabled us to predict long-term implant survival with a small sample of patients followed for a relatively short period of time. The purpose of our systematic review was to validate the predictive value of two-year RSA results on long-term survival of different types of primary total hip arthroplasty stems.

Methods

We systematically reviewed literature to determine the maximum total point motion (MTPM), distal migration and rotation of stem designs and correlated these values to survival rates for aseptic loosening of these specific stems in arthroplasty registries.

Results

We included 32 studies describing migration of 15 different stem designs. The mean MTPM for straight polished cemented stems was 1.35 mm, for other cemented stems 0.83 mm and for other uncemented stems 1.50 mm. No data were available for the uncemented collared stem. Mean distal migration for straight polished cemented stems was 1.24 mm, for other cemented stems 0.26 mm, the uncemented collared stem 0.40 mm and for other uncemented stems 0.66 mm. Internal rotation was presented for 13 stems and all stems rotated into retroversion. All stems showed 10-year survival rates of >97% corrected for aseptic loosening.

Discussion

Reporting RSA results in a universal way including interpretation of outliers could improve the predictive value of RSA, allowing this technique to be an important tool during the phased introduction of new implant designs. However, a quality assessment of the data by an experienced reviewer is essential.
Hemiarthroplasties after Hip Fractures in Norway and Sweden: A Collaboration between the Norwegian and Swedish National Registries
Authors: Gjertsen Jan-Erik , Fenstad Anne Marie , Leonardsson Olof , Engesæter Lars Birger , Kärrholm Johan , Furnes Ove , Garellick Göran , Rogmark Cecilia
Published: November 2014

National registration of hemiarthroplasties after hip fractures has been established in both Norway and Sweden. We aimed to investigate differences in demographics, choice of implant selection, surgical approaches, and reoperations between the Norwegian Hip Fracture Register (NHFR) and the Swedish Hip Arthroplasty Register (SHAR). As part of the Nordic Arthroplasty Register Association (NARA) project a common hemiarthroplasty dataset has been established. 36,989 primary hemiarthroplasties (HAs) for acute hip fractures reported to NHFR (n = 12,761) and SHAR (n = 24,228) for the period 2005-2010 were included. Cemented prostheses were used in 78% of the operations in Norway and in 95% of the patients in Sweden. In Norway HAs almost exclusively had bipolar design (98%), whereas in Sweden HAs with unipolar design were used in 42% of the cases. Monoblock (non-modular) prostheses were uncommon, but still more frequently used in Sweden than in Norway (6.9% and 2.1% respectively). The lateral approach was more common in Norway (83%) than in Sweden (52%), where the posterior approach was used in 42% of the cases. The five-year survival of all HAs was 95.5% (95% CI: 94.8-96.2) in Norway and 94.8% (95% CI: 94.4-95.3) in Sweden. We concluded that surprisingly large differences between the two countries in demographics, implant design, and surgical technique had been revealed. This common dataset enables further investigations of the impact of these differences on revision rates and mortality.
Anterior Minimally Invasive Approach for Total Hip Replacement: Five-Year Survivorship and Learning Curve
Authors: Müller Daniel A. , Zingg Patrick O. , Dora Claudio
Published: November 2014

Opponents associate minimally invasive total hip replacement (THR) with additional risks, potentially resulting in increased implant failure rates. The purpose was to document complications, quality of implant positioning and five-year survivorship of THR using the AMIS approach and to test the hypothesis that eventual high complication and revision rates would be limited to an early series and be avoided by junior surgeons who get trained by a senior surgeon. A consecutive series of 150 primary THR implanted during the introduction of the AMIS technique in the department was retrospectively analysed for complications, implant positioning and implant survival after a minimum of five years. Survivorship curves of implants were compared between different surgeons and time periods. Due to implant revision for any reason the five-year survival rate was 94.6%, 78.9% for the first 20 and 96.8% for the following 130 AMIS procedures (p = 0.001). The hazard ratio for implant failure was 0.979 indicating a risk reduction of 2% every further case. The five-year implant survivorship of those procedures performed by two junior surgeons was 97.7%. We conclude that adoption of AMIS temporarily exposed patients to a higher risk of implant revisions, which normalised after the first 20 cases and that experience from a single surgeon's learning curve could effectively be taught to junior surgeons.
The vulnerable myocardium
Authors: Bode C. , Bugger H.
Published: November 2014

Cardiovascular disease is the major cause of morbidity and mortality in subjects suffering from diabetes mellitus. While coronary artery disease is the leading cause of cardiac complications in diabetics, it is widely recognized that diabetes increases the risk for the development of heart failure independently of coronary heart disease and hypertension. This increased susceptibility of the diabetic heart to develop structural and functional impairment is termed diabetic cardiomyopathy. The number of different mechanisms proposed to contribute to diabetic cardiomyopathy is steadily increasing and underlines the complexity of this cardiac entity.

In this review the mechanisms that account for the increased myocardial vulnerability in diabetic cardiomyopathy are discussed.
The dyskerin ribonucleoprotein complex as an OCT4/SOX2 coactivator in embryonic stem cells
Authors: Fong Yick W , Ho Jaclyn J , Inouye Carla , Tjian Robert
Published: November 2014

Acquisition of pluripotency is driven largely at the transcriptional level by activators OCT4, SOX2, and NANOG that must in turn cooperate with diverse coactivators to execute stem cell-specific gene expression programs. Using a biochemically defined in vitro transcription system that mediates OCT4/SOX2 and coactivator-dependent transcription of the Nanog gene, we report the purification and identification of the dyskerin (DKC1) ribonucleoprotein complex as an OCT4/SOX2 coactivator whose activity appears to be modulated by a subset of associated small nucleolar RNAs (snoRNAs). The DKC1 complex occupies enhancers and regulates the expression of key pluripotency genes critical for self-renewal in embryonic stem (ES) cells. Depletion of DKC1 in fibroblasts significantly decreased the efficiency of induced pluripotent stem (iPS) cell generation. This study thus reveals an unanticipated transcriptional role of the DKC1 complex in stem cell maintenance and somatic cell reprogramming.
A genetically attenuated malaria vaccine candidate based on P. falciparum b9/slarp gene-deficient sporozoites
Authors: van Schaijk Ben C L , Ploemen Ivo H J , Annoura Takeshi , Vos Martijn W , Foquet Lander , van Gemert Geert-Jan , Chevalley-Maurel Severine , van de Vegte-Bolmer Marga , Sajid Mohammed , Franetich Jean-Francois , Lorthiois Audrey , Leroux-Roels Geert , Meuleman Philip , Hermsen Cornelius C , Mazier Dominique , Hoffman Stephen L , Janse Chris J , Khan Shahid M , Sauerwein Robert W
Published: November 2014

A highly efficacious pre-erythrocytic stage vaccine would be an important tool for the control and elimination of malaria but is currently unavailable. High-level protection in humans can be achieved by experimental immunization with Plasmodium falciparum sporozoites attenuated by radiation or under anti-malarial drug coverage. Immunization with genetically attenuated parasites (GAP) would be an attractive alternative approach. In this study, we present data on safety and protective efficacy using sporozoites with deletions of two genes, that is the newly identified b9 and slarp, which govern independent and critical processes for successful liver-stage development. In the rodent malaria model, PbΔb9ΔslarpGAP was completely attenuated showing no breakthrough infections while efficiently inducing high-level protection. The human PfΔb9ΔslarpGAP generated without drug resistance markers were infective to human hepatocytes in vitro and to humanized mice engrafted with human hepatocytes in vivo but completely aborted development after infection. These findings support the clinical development of a PfΔb9ΔslarpSPZ vaccine.
Development and evolution of detachment faulting along 50 km of the Mid‐Atlantic Ridge near 16.5°N
Authors: Smith Deborah K. , Schouten Hans , Dick Henry J. B. , Cann Johnson R. , Salters Vincent , Marschall Horst R. , Ji Fuwu , Yoerger Dana , Sanfilippo Alessio , Parnell‐Turner Ross , Palmiotto Camilla , Zheleznov Alexei , Bai Hailong , Junkin Will , Urann Ben , Dick Spencer , Sulanowska Margaret , Lemmond Peter , Curry Scott
Published: November 2014

A multifaceted study of the slow spreading Mid‐Atlantic Ridge (MAR) at 16.5°N provides new insights into detachment faulting and its evolution through time. The survey included regional multibeam bathymetry mapping, high‐resolution mapping using AUV Sentry, seafloor imaging using the TowCam system, and an extensive rock‐dredging program. At different times, detachment faulting was active along ∼50 km of the western flank of the study area, and may have dominated spreading on that flank for the last 5 Ma. Detachment morphologies vary and include a classic corrugated massif, noncorrugated massifs, and back‐tilted ridges marking detachment breakaways. High‐resolution Sentry data reveal a new detachment morphology; a low‐angle, irregular surface in the regional bathymetry is shown to be a finely corrugated detachment surface (corrugation wavelength of only tens of meters and relief of just a few meters). Multiscale corrugations are observed 2–3 km from the detachment breakaway suggesting that they formed in the brittle layer, perhaps by anastomosing faults. The thin wedge of hanging wall lavas that covers a low‐angle (6°) detachment footwall near its termination are intensely faulted and fissured; this deformation may be enhanced by the low angle of the emerging footwall. Active detachment faulting currently is limited to the western side of the rift valley. Nonetheless, detachment fault morphologies also are present over a large portion of the eastern flank on crust >2 Ma, indicating that within the last 5 Ma parts of the ridge axis have experienced periods of two‐sided detachment faulting.
Effects of turbulence on mixed‐phase deep convective clouds under different basic‐state winds and aerosol concentrations
Authors: Lee Hyunho , Baik Jong‐Jin , Han Ji‐Young
Published: November 2014

The effects of turbulence‐induced collision enhancement (TICE) on mixed‐phase deep convective clouds are numerically investigated using a 2‐D cloud model with bin microphysics for uniform and sheared basic‐state wind profiles and different aerosol concentrations. Graupel particles account for the most of the cloud mass in all simulation cases. In the uniform basic‐state wind cases, graupel particles with moderate sizes account for some of the total graupel mass in the cases with TICE, whereas graupel particles with large sizes account for almost all the total graupel mass in the cases without TICE. This is because the growth of ice crystals into small graupel particles is enhanced due to TICE. The changes in the size distributions of graupel particles due to TICE result in a decrease in the mass‐averaged mean terminal velocity of graupel particles. Therefore, the downward flux of graupel mass, and thus the melting of graupel particles, is reduced due to TICE, leading to a decrease in the amount of surface precipitation. Moreover, under the low aerosol concentration, TICE increases the sublimation of ice particles, consequently playing a partial role in reducing the amount of surface precipitation. The effects of TICE are less pronounced in the sheared basic‐state wind cases than in the uniform basic‐state wind cases because the number of ice crystals is much smaller in the sheared basic‐state wind cases than in the uniform basic‐state wind cases. Thus, the size distributions of graupel particles in the cases with and without TICE show little difference.
Climate coupling between temperature, humidity, precipitation, and cloud cover over the Canadian Prairies
Authors: Betts Alan K. , Desjardins Raymond , Worth Devon , Beckage Brian
Published: November 2014

This analysis uses over 50 years of hourly observations of temperature, relative humidity, and opaque cloud cover and daily precipitation from 11 climate stations across the Canadian Prairies to analyze the monthly, seasonal, and long‐term climate coupling in the warm season. On climate time scales, temperature depends on cloud forcing, while relative humidity depends on precipitation. The monthly climate depends on both opaque cloud cover for the current month and precipitation for both the present and past 2 months in summer. Multiple linear regression shows that anomalies of opaque cloud and precipitation explain 60–80% of the variance in the diurnal temperature range, afternoon relative humidity, and lifting condensation level on monthly time scales. We analyze the internal coupling of diurnal climate observables as a further guide to evaluating models. We couple the statistics to simplified energy and water budgets for the Prairies in the growing season. The opaque cloud observations have been calibrated against the incoming shortwave and longwave fluxes. We estimate that the drydown of total water storage on the landscape damps 56% of precipitation anomalies for the growing season on large spatial scales, although this drydown increases evapotranspiration. This couples the climatological surface fluxes to four key observables: cloud forcing, precipitation, temperature, and humidity. We estimate a climatological evaporative fraction of 0.61 for the Prairies. The observational relationships of the coupled Prairie climate system across time scale will be useful for evaluating these coupled processes in models for weather and seasonal forecasting and climate simulation.
Recapillarity: Electrochemically Controlled Capillary Withdrawal of a Liquid Metal Alloy from Microchannels
Authors: Khan Mohammad R. , Trlica Chris , Dickey Michael D.
Published: November 2014

This paper describes the mechanistic details of an electrochemical method to control the withdrawal of a liquid metal alloy, eutectic gallium indium (EGaIn), from microfluidic channels. EGaIn is one of several alloys of gallium that are liquid at room temperature and form a thin (nm scale) surface oxide that stabilizes the shape of the metal in microchannels. Applying a reductive potential to the metal removes the oxide in the presence of electrolyte and induces capillary behavior; we call this behavior “recapillarity” because of the importance of electrochemical reduction to the process. Recapillarity can repeatably toggle on and off capillary behavior by applying voltage, which is useful for controlling the withdrawal of metal from microchannels. This paper explores the mechanism of withdrawal and identifies the applied current as the key factor dictating the withdrawal velocity. Experimental observations suggest that this current may be necessary to reduce the oxide on the leading interface of the metal as well as the oxide sandwiched between the wall of the microchannel and the bulk liquid metal. The ability to control the shape and position of a metal using an applied voltage may prove useful for shape reconfigurable electronics, optics, transient circuits, and microfluidic components.
An Interface‐Induced Co‐Assembly Approach Towards Ordered Mesoporous Carbon/Graphene Aerogel for High‐Performance Supercapacitors
Authors: Liu Ruili , Wan Li , Liu Shaoqing , Pan Lixia , Wu Dongqing , Zhao Dongyuan
Published: November 2014

Hierarchically porous composites with mesoporous carbon wrapping around the macroporous graphene aerogel can combine the advantages of both components and are expected to show excellent performance in electrochemical energy devices. However, the fabrication of such composites is challenging due to the lack of an effective strategy to control the porosity of the mesostructured carbon layers. Here an interface‐induced co‐assembly approach towards hierarchically mesoporous carbon/graphene aerogel composites, possessing interconnected macroporous graphene networks covered by highly ordered mesoporous carbon with a diameter of ≈9.6 nm, is reported. And the orientation of the mesopores (vertical or horizontal to the surface of the composites) can be tuned by the ratio of the components. As the electrodes in supercapacitors, the resulting composites demonstrate outstanding electrochemical performances. More importantly, the synthesis strategy provides an ideal platform for hierarchically porous graphene composites with potential for energy storage and conversion applications.
Photoinduced Charge‐Carrier Dynamics of Phototransistors Based on Perylene Diimide/Reduced Graphene Oxide Core/Shell p–n Junction Nanowires
Authors: Yu Hojeong , Joo Piljae , Lee Dajeong , Kim Byeong‐Su , Oh Joon Hak
Published: November 2014

The tailored fabrication of multicomponent nanostructures that can exhibit superior or unique optoelectronic properties compared with those of the single‐component system is highly desirable for fundamental studies of charge transport mechanisms and novel applications with advanced functions. To achieve efficient charge transport and high photoresponsivity, core/shell p–n heterojunction nanowires (NWs) are fabricated using N,N′‐bis(2‐phenylethyl)‐perylene‐3,4:9,10‐tetracarboxylic diimide (BPE‐PTCDI) and reduced graphene oxide (rGO) in solution phase. BPE‐PTCDI/rGO core/shell NWs exhibit significantly enhanced photocurrent and faster charge compensation rate under irradiation, compared with pure BPE‐PTCDI NWs. BPE‐PTCDI NW core mainly acts as a light absorption layer, whereas rGO shell functions as a charge transport channel and contributes to a large electrical conductivity. Accordingly, the outstanding light‐detecting performance of BPE‐PTCDI/rGO NWs results from the synergistic combination of the favorable optical and electrical properties of each of the constituent materials. Intriguingly, BPE‐PTCDI/rGO NW organic phototransistors (OPTs) show charge compensation behaviors opposite to those of pure BPE‐PTCDI NW‐OPTs, which is interpreted with a model concerning charge trapping energy levels. The results obtained herein demonstrate great promise for use of carbon‐based multicomponent core/shell nanomaterials in photodetectors, and the developed methodology provides insights into the quantitative analysis of the photogenerated charge‐carrier dynamics of multicomponent semiconducting systems.
Metal‐Free Regioselective β‐Alkylation of Pyrroles with Carbonyl Compounds and Hydrosilanes: Use of a Brønsted Acid as a Catalyst
Authors: Nomiyama Shota , Tsuchimoto Teruhisa
Published: November 2014

A Brønsted acid, trifluoromethanesulfonimide [HN(SO2CF3)2], was found to catalyze reductive β‐alkylation of pyrroles with carbonyl compounds and hydrosilanes. This metal‐free process features lower catalyst loadings compared to the original indium variant and exclusive generation of β‐alkylpyrroles.

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Efficient Catalysis of the Aerobic Baeyer–Villiger Oxidation over a Bifunctional Catalyst Based on Cobalt Tetraphenylporphyrin Intercalated into Zn2Al Hydrotalcite
Authors: Zhou Weiyou , Tian Peng , Sun Fu'an , He Mingyang , Chen Zaixin
Published: November 2014

On the basis of the mechanism of Baeyer–Villiger (B‐V) oxidation, a bifunctional catalyst based on tetra(4‐sulfonato‐phenyl)porphinato‐cobalt(II) anion (CoTSPP) intercalated into Zn2Al hydrotalcite (Zn2Al‐LDH; LDH=layered double hydroxide) was designed and prepared. XRD, FTIR, DR UV/vis, TG/DTA, and SEM characterization indicate that CoTSPP molecular has been successfully intercalated into the layers of Zn2Al‐LDH. The catalytic activity of the synthesized hybrid in the B‐V oxidation for various ketones is excellent. Control experiments indicated that the catalyst has a bifunctional role in the reactions. The protocol opens up new perspectives in the rational design of efficient catalytic systems.
Iron phthalocyanine as new efficient catalyst for catalytic transfer hydrogenation of simple aldehydes and ketones
Authors: Bata Péter , Notheisz Ferenc , Kluson Peter , Zsigmond Ágnes
Published: November 2014

Catalytic transfer hydrogenation (CTH) of various aldehydes and ketones was studied using iron phthalocyanine catalyst, in order to substitute the typically used rare transition metals (Ir, Rh, Ru) with an easily available and less expensive metal. Iron phthalocyanine was found to be an efficient hydrogenation catalyst and its immobilized version was successfully prepared. The immobilized iron phthalocyanine was also active in the CTH reaction of various carbonyl compounds, and it was easy to handle and possible to recycle. Copyright © 2014 John Wiley & Sons, Ltd.
One‐pot synthesis of polyfluoroterphenyls via palladium‐catalyzed Suzuki–Miyaura coupling of chlorobromobenzene and CH bond functionalization of perfluoroarenes
Authors: Ma Xiaowei , Gu Ningning , Liu Yan , Liu Ping , Xie Jianwei , Dai Bin , Liu Zhiyong
Published: November 2014

An efficient tandem route for the synthesis of polyfluoroterphenyl derivatives has been developed. The target compounds were obtained in moderate to good yields by a Pd(OAc)2‐catalyzed three‐component coupling reaction involving palladium‐catalyzed direct CH activation of perfluoroarenes. This in turn will set the stage for a wide application of this useful reaction for the synthesis of fluorinated liquid crystal compounds containing the privileged polyfluoroterphenyl structure. Copyright © 2014 John Wiley & Sons, Ltd.
Fabrication by photoinitiated polymerization and characterization of millimeter‐size poly(divinyl benzene) hollow foam shells
Authors: Yang Yi , Luo Xuan , Li Zefu , Wang Jia , Wei Zhijun , Wang Xiaojun , Zhang Lin
Published: November 2014

In this study, millimeter‐size compound droplets were prepared easily by a one‐step microfluidic method. We varied the diameter and wall thickness of the shells over a wide range by setting the flow rate. Poly(divinyl benzene) (PDVB) shells with a 3–4.8 mm diameter were fabricated through photopolymerization and supercritical drying. The gel point of photopolymerization was monitored by a rotational rheometer. Moreover, the influence of the oil‐soluble photoinitiator phenyl bis(2,4,6‐trimethyl benzoyl) phosphine oxide (BAPO) on the properties of the foam shell were investigated by transmission electron microscopy, scanning electron microscopy, and nitrogen sorption measurements. Significant differences in the mechanical properties and porous features were obtained for different BAPO concentrations. The surface areas of the foam shells decreased, and the densities of the foam shells increased with increasing BAPO concentration. In addition, the nonconcentricity and out‐of‐roundness values were mainly less than 7 and 3%, respectively, for most of the shells. The results indicate that the PDVB hollow foam shells are a promising inertial fusion energy target. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41625.
Thermal property, morphology, and hydrolysis ability of poly(lactic acid)/chitosan nanocomposites using polyethylene oxide
Authors: Chinh Nguyen Thuy , Trang Nguyen Thi Thu , Thanh Dinh Thi Mai , Hang To Thi Xuan , Giang Nguyen Vu , Quan Pham Minh , Dung Nguyen Tien , Hoang Thai
Published: November 2014

Poly(lactic acid) (PLA) and chitosan (CS) are two natural resource polymers, which have been applied widely into different fields. Polymer composites based on PLA and CS have some advantages such as good adhesion, biodegradability, biocompatibility, and high stability. They can be prepared by different methods including the solution, emulsion, and electrospinning methods. In this work, the PLA/chitosan nanocomposites were prepared by solution method using poly(ethylene oxide) (PEO) as a compatibilizer in order to improve interaction and dispersion between PLA and CS phases. The characterization and morphology of the above nanocomposites were determined by Fourier Transform Infrared Spectroscopy (FTIR), thermograviety analysis, differential scanning calorimetry, and scanning electron microscopy. Hydrolysis ability of PLA/CS nanocomposites with and without PEO was also investigated in acid and phosphate buffer solutions. The obtained results showed the compatibility between PLA and CS phases in the PLA/CS nanocomposites using PEO was improved clearly and weight loss of PLA/CS/PEO nanocomposites in the above environments lower than that of PLA/CS nanocomposites. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41690.