bluuebunny/crossref_metadata_2025 huggingface dataset:
Does Prior Specification Matter in Hotspot Identification and Before–After Road Safety Studies?
Authors: Heydari Shahram , Miranda-Moreno Luis F. , Amador Luis Esteban
Published: February 2014

This study investigated the effects of prior assumptions in applications of full Bayes methods in road safety analysis. The effect of prior choice was evaluated in the accuracy of model parameters, hotspot identification, goodness of fit, and a treatment effectiveness index in before–after studies. Particular attention was devoted to conditions with a lack of data, which were referenced as the low-mean and small-sample problem. In this research, informative, semi-informative, and noninformative priors were determined on the basis of past published studies. A simulation framework was used to evaluate various scenarios of sample size and crash occurrence mean. Quasi-simulated data were generated on the basis of two empirical databases of divided and undivided rural highway segments in New York and Texas. Various sample mean values were obtained on the basis of time period (number of years) and classifying accidents in fatal–injury and total accidents. The outcomes under low-mean and small-sample conditions were found to be significantly biased. However, the introduction of informative priors can make observational before–after studies feasible when a few observations from treatment or comparison sites are used. Informative priors can help provide more accurate estimates of the effectiveness of the treatment. Finally, in accordance with previous works, the inverse dispersion parameter was significantly affected by prior specifications; nevertheless, regression parameters, goodness of fit, and hotspot identification were less sensitive to prior choices.
Short-Term Forecasting of Traffic Volume
Authors: Lin Lei , Wang Qian , Sadek Adel W.
Published: February 2014

Although several methods for short-term forecasting of traffic volume have recently been developed, the literature lacks studies that focus on how to choose the appropriate prediction method on the basis of the statistical characteristics of the data set. This study first diagnosed the predictability of four traffic volume data sets on the basis of various statistical measures, including (a) complexity analysis methods, such as the delay time and embedding dimension method and the approximate entropy method; (b) nonlinearity analysis methods, such as the time reversibility of surrogate data; and (c) long-range dependency analysis techniques, such as the Hurst exponent. After the data sets were diagnosed, three models for short-term prediction of traffic volume were applied: (a) seasonal autoregressive integrated moving average (SARIMA), (b) k nearest neighbor (k-NN), and (c) support vector regression (SVR). The results from the statistical data diagnosis methods were then correlated to the performance results of the three prediction methods on the four data sets to determine the means for choosing the appropriate prediction method. The results revealed that SVR was more suitable for nonlinear data sets, while SARIMA and k-NN were more appropriate for linear data sets. The data diagnosis results were also used to devise a selection process for the parameters of the prediction models, such as the length of the training data set for SARIMA and SVR, the average number of nearest neighbors for k-NN, and the input vector length for k-NN and SVR.
Multiresolution Visualization Tools to Aid in Conducting Road Safety Audits
Authors: Shelton Jeffrey , Valdez Gabriel A. , Sanchez Gus , Leos Gerardo
Published: February 2014

Typical road safety audits use site investigations in addition to historical data to make recommendations. Recent approaches have used simulation modeling to derive surrogate measures to analyze the potential for collisions, driving simulators to analyze human behavior, or other visualization tools to analyze geometric design characteristics. None of these tools can capture the dynamics of proposed changes that subsequently alter traffic patterns. Each proposed improvement has an influence on traffic patterns and must be captured at a regional level to determine whether vehicles choose the same path or defer to an alternative one. This study explored new methods to supplement the Road Safety Audit process. The study used visualization tools to assess the performance of each proposed improvement strategy by conducting a more thorough comprehensive safety study with multiresolution modeling methods in situations when suggested countermeasures would almost certainly redistribute traffic to alternative routes. A case study was selected in which an audit team performed a safety audit of a diamond interchange in El Paso, Texas, that experienced a high number of collisions during peak hours. The visualization of the proposed improvement scenarios helped the Texas Department of Transportation understand better how mitigation strategies would influence traffic flow in and around the study area or whether the proposed changes improved safety or merely shifted the problem to alternative locations. The use of visualization tools can help convey proposed improvements to the public.
Surgical outcomes in spinal cord ependymomas and the importance of extent of resection in children and young adults
Authors: Safaee Michael , Oh Michael C. , Mummaneni Praveen V. , Weinstein Philip R. , Ames Christopher P. , Chou Dean , Berger Mitchel S. , Parsa Andrew T. , Gupta Nalin
Published: February 2014

Object

Ependymomas are a common type of CNS tumor in children, although only 13% originate from the spinal cord. Aside from location and extent of resection, the factors that affect outcome are not well understood.

Methods

The authors performed a search of an institutional neuropathology database to identify all patients with spinal cord ependymomas treated over the past 20 years. Data on patient age, sex, clinical presentation, symptom duration, tumor location, extent of resection, use of radiation therapy, surgical complications, presence of tumor recurrence, duration of follow-up, and residual symptoms were collected. Pediatric patients were defined as those 21 years of age or younger at diagnosis. The extent of resection was defined by the findings of the postoperative MR images.

Results

A total of 24 pediatric patients with spinal cord ependymomas were identified with the following pathological subtypes: 14 classic (Grade II), 8 myxopapillary (Grade I), and 2 anaplastic (Grade III) ependymomas. Both anaplastic ependymomas originated in the intracranial compartment and spread to the spinal cord at recurrence. The mean follow-up duration for patients with classic and myxopapillary ependymomas was 63 and 45 months, respectively. Seven patients with classic ependymomas underwent gross-total resection (GTR), while 4 received subtotal resection (STR), 2 received STR as well as radiation therapy, and 1 received radiation therapy alone. All but 1 patient with myxopapillary ependymomas underwent GTR. Three recurrences were identified in the Grade II group at 45, 48, and 228 months. A single recurrence was identified in the Grade I group at 71 months. The mean progression-free survival (PFS) was 58 months in the Grade II group and 45 months in the Grade I group.

Conclusions

Extent of resection is an important prognostic factor in all pediatric spinal cord ependymomas, particularly Grade II ependymomas. These data suggest that achieving GTR is more difficult in the upper spinal cord, making tumor location another important factor. Although classified as Grade I lesions, myxopapillary ependymomas had similar outcomes when compared with classic (Grade II) ependymomas, particularly with respect to PFS. Long-term complications or new neurological deficits were rare. Among patients with long-term follow-up, those who underwent GTR had a recurrence rate of 20% compared with 40% among those with STR or biopsy only, suggesting that extent of resection is perhaps a more important prognostic factor than histological grade in predicting PFS, which has been suggested by other data in the literature. Given the relative paucity of these lesions, collaborative multiinstitutional studies are needed, and such efforts should also focus on molecular and genetic analysis to refine the current classification system.
Editorial Vol.1(3)
Authors: Muazzam MG
Published: February 2014

DOI: http://dx.doi.org/10.3329.bjms.v1i3.17908Bangladesh Journal of Medical Science Vol.1(3) 1994 pp.4
Effect of various extracts of Tabernaemontana divaricata on haloperidol induced catalepsy in rats
Authors: Raj Chanchal N. , Balasubramaniam A. , Nadeem Sayyed
Published: February 2014

Parkinsons disease (PD) is one of the neurodegenerative diseases with selective loss of dopamine neurons of the substantia nigra pars compacta. In the present study, anti-cataleptic activity of Tabernaemontana divaricata leaves extracts viz. aqueous and ethanolic at different doses (50, 100 and 150 mg/kg i.p.) were studied using haloperidol (1 mg/kg, i.p.) induced catalepsy in rats which is a useful animal model for screening drugs for Parkinsons disease. Both the extracts were found to reduce catalepsy significantly (P<0.001) as compared to the haloperidol treated rats showing greater effect at 150 mg/kg i.p. dose. Thus the present study reveals the anti-cataleptic activity of Tabernaemontana divaricata evaluating the traditional folklore medicinal use of the plant.DOI: http://dx.doi.org/10.3329/icpj.v3i3.17891 International Current Pharmaceutical Journal, February 2014, 3(3): 240-242
MicroRNA-200c Inhibits Apoptosis in Pituitary Adenoma Cells by Targeting the PTEN/Akt Signaling Pathway
Authors: Liao Chuangxin , Chen Wenli , Fan Xiang , Jiang Xiaobing , Qiu Lubing , Chen Chunhua , Zhu Yonghong , Wang Haijun
Published: February 2014

MicroRNAs (miRNAs) are important regulators that are involved in the development of different types of tumors. MicroRNA-200c (miR-200c) has been characterized as a tumor suppressor or oncogene in different cancers. However, the role of miR-200c in pituitary tumorigenesis remains unknown.
We observed that miR-200c was overexpressed in pituitary adenoma cell lines. We transfected a miR-200c inhibitor into pituitary adenoma cells (MMQ cell line) to inhibit miR-200c expression and found that the percentage of apoptotic MMQ cells increased. Using bioinformatics analyses, we predicted
that the tumor suppressor gene PTEN was targeted by miR-200c, and we confirmed the presence of a functional miR-200c binding site in the 3′-UTR of PTEN using luciferase reporter assays. We determined that the inhibition of miR-200c expression can upregulate PTEN expression and decrease
the expression of phosphorylated Akt (p-Akt). Furthermore, the siRNA-mediated knockdown of PTEN abrogated the effect of inhibiting miR-200c expression. Taken together, these findings suggest that miR-200c regulates pituitary tumor formation through the PTEN/Akt signaling pathway. Therefore,
we propose that the inhibition of miR-200c could have therapeutic potential in pituitary adenoma.
Sources and light absorption of water-soluble organic carbon aerosols in the outflow from northern China
Authors: Kirillova E. N. , Andersson A. , Han J. , Lee M. , Gustafsson Ö.
Published: February 2014

Abstract. High loadings of anthropogenic carbonaceous aerosols in Chinese air influence the air quality for over one billion people and impact the regional climate. A large fraction (17–80%) of this aerosol carbon is water-soluble, promoting cloud formation and thus climate cooling. Recent findings, however, suggest that water-soluble carbonaceous aerosols also absorb sunlight, bringing additional direct and indirect climate warming effects, yet the extent and nature of light absorption by this water-soluble "brown carbon" and its relation to sources is poorly understood. Here, we combine source estimates constrained by dual carbon isotopes with light-absorption measurements of water-soluble organic carbon (WSOC) for a March 2011 campaign at the Korea Climate Observatory at Gosan (KCOG), a receptor station in SE Yellow Sea for the outflow from northern China. The mass absorption cross section at 365 nm (MAC365) of WSOC for air masses from N. China were in general higher (0.8–1.1 m2 g−1), than from other source regions (0.3–0.8 m2 g−1). However, this effect corresponds to only 2–10% of the radiative forcing caused by light absorption by elemental carbon. Radiocarbon constraints show that the WSOC in Chinese outflow had significantly higher fraction fossil sources (30–50%) compared to previous findings in S. Asia, N. America and Europe. Stable carbon (δ13C) measurements were consistent with aging during long-range air mass transport for this large fraction of carbonaceous aerosols.
Secondary organic aerosol yields of 12-carbon alkanes
Authors: Loza C. L. , Craven J. S. , Yee L. D. , Coggon M. M. , Schwantes R. H. , Shiraiwa M. , Zhang X. , Schilling K. A. , Ng N. L. , Canagaratna M. R. , Ziemann P. J. , Flagan R. C. , Seinfeld J. H.
Published: February 2014

Abstract. Secondary organic aerosol (SOA) yields were measured for cyclododecane, hexylcyclohexane, n-dodecane, and 2-methylundecane under high-NOx conditions, in which alkyl proxy radicals (RO2) react primarily with NO, and under low-NOx conditions, in which RO2 reacts primarily with HO2. Experiments were run until 95–100% of the initial alkane had reacted. Particle wall loss was evaluated as two limiting cases using a new approach that requires only suspended particle number-size distribution data and accounts for size-dependent particle wall losses and condensation. SOA yield differed by a factor of 2 between the two limiting cases, but the same trends among alkane precursors were observed for both limiting cases. Vapor-phase wall losses were addressed through a modeling study and increased SOA yield uncertainty by approximately 30%. SOA yields were highest from cyclododecane under both NOx conditions. SOA yields ranged from 3.3% (dodecane, low-NOx conditions) to 160% (cyclododecane, high-NOx conditions). Under high-NOx conditions, SOA yields increased from 2-methylundecane < dodecane ~ hexylcyclohexane < cyclododecane, consistent with previous studies. Under low-NOx conditions, SOA yields increased from 2-methylundecane ~ dodecane < hexylcyclohexane < cyclododecane. The presence of cyclization in the parent alkane structure increased SOA yields, whereas the presence of branch points decreased SOA yields due to increased vapor-phase fragmentation. Vapor-phase fragmentation was found to be more prevalent under high-NOx conditions than under low-NOx conditions. For different initial mixing ratios of the same alkane and same NOx conditions, SOA yield did not correlate with SOA mass throughout SOA growth, suggesting kinetically limited SOA growth for these systems.
Separating mixtures of aerosol types in airborne High Spectral Resolution Lidar data
Authors: Burton S. P. , Vaughan M. A. , Ferrare R. A. , Hostetler C. A.
Published: February 2014

Abstract. Knowledge of aerosol type is important for determining the magnitude and assessing the consequences of aerosol radiative forcing, and can provide useful information for source attribution studies. However, atmospheric aerosol is frequently not a single pure type, but instead occurs as a mixture of types, and this mixing affects the optical and radiative properties of the aerosol. This paper extends the work of earlier researchers by using the aerosol intensive parameters measured by the NASA Langley Research Center airborne High Spectral Resolution Lidar (HSRL-1) to develop a comprehensive and unified set of rules for characterizing the external mixing of several key aerosol intensive parameters: extinction-to-backscatter ratio (i.e., lidar ratio), backscatter color ratio, and depolarization ratio. We present the mixing rules in a particularly simple form that leads easily to mixing rules for the covariance matrices that describe aerosol distributions, rather than just single values of measured parameters. These rules can be applied to infer mixing ratios from the lidar-observed aerosol parameters, even for cases without significant depolarization. We demonstrate our technique with measurement curtains from three HSRL-1 flights which exhibit mixing between two aerosol types, urban pollution plus dust, marine plus dust, and smoke plus marine. For these cases, we infer a time-height cross-section of extinction mixing ratio along the flight track, and partition aerosol extinction into portions attributed to the two pure types.
Retrieving hurricane wind speeds using cross-polarization C-band measurements
Authors: van Zadelhoff G.-J. , Stoffelen A. , Vachon P. W. , Wolfe J. , Horstmann J. , Belmonte Rivas M.
Published: February 2014

Abstract. Hurricane-force wind speeds can have a large societal impact and in this paper microwave C-band cross-polarized (VH) signals are investigated to assess if they can be used to derive extreme wind-speed conditions. European satellite scatterometers have excellent hurricane penetration capability at C-band, but the vertically (VV) polarized signals become insensitive above 25 m s−1. VV and VH polarized backscatter signals from RADARSAT-2 SAR imagery acquired during severe hurricane events were compared to collocated SFMR wind measurements acquired by NOAA's hurricane-hunter aircraft. From this data set a geophysical model function (GMF) at strong-to-extreme/severe wind speeds (i.e., 20 m s−1 < U10 < 45 m s−1) is derived. Within this wind speed regime, cross-polarized data showed no distinguishable loss of sensitivity and as such, cross-polarized data can be considered a good candidate for the retrieval of strong-to-severe wind speeds from satellite instruments. The upper limit of 45 m s−1 is defined by the currently available collocated data. The validity of the derived relationship between wind speed and VH backscatter has been evaluated by comparing the cross-polarized signals to two independent wind-speed data sets (i.e., short-range ECMWF numerical weather prediction (NWP) model forecast winds and the NOAA best estimate 1-minute maximum sustained winds). Analysis of the three comparison data sets confirm that cross-polarized signals from satellites will enable the retrieval of strong-to-severe wind speeds where VV or horizontal (HH) polarization data has saturated. The VH backscatter increases exponentially with respect to wind speed (linear against VH [dB]) and a near-real-time assessment of maximum sustained wind speed is possible using VH measurements. VH measurements thus would be an extremely valuable complement on next-generation scatterometers for hurricane forecast warnings and hurricane model initialization.
Residence times and mixing of water in river banks: implications for recharge and groundwater – surface water exchange
Authors: Unland N. P. , Cartwright I. , Cendón D. I. , Chisari R.
Published: February 2014

Abstract. The residence time of groundwater within 50 m of the Tambo River, South East Australia, has been estimated through the combined use of 3H and 14C. Groundwater residence times increase towards the Tambo River which implies a gaining river system and not increasing bank storage with proximity to the Tambo River. Major ion concentrations and δ2H and δ18O values of bank water also indicate that bank infiltration does not significantly impact groundwater chemistry under baseflow and post-flood conditions, suggesting that the gaining nature of the river may be driving the return of bank storage water back into the Tambo River within days of peak flood conditions. The covariance between 3H and 14C indicates the leakage and mixing between old (~17 200 yr) groundwater from a semi-confined aquifer and younger groundwater (<100 yr) near the river where confining layers are less prevalent. The presence of this semi-confined aquifer has also been used to help explain the absence of bank storage, as rapid pressure propagation into the semi-confined aquifer during flooding will minimise bank infiltration. This study illustrates the complex nature of river groundwater interactions and the potential downfall in assuming simple or idealised conditions when conducting hydrogeological studies.
Quantitative changes within the peripheral blood CD8highCD57+ T-cell subpopulation of patients with advanced renal cell carcinoma
Authors: Strioga Marius , Pašukonienė Vita , Dobrovolskienė Neringa , Petraitis Tadas , Kazlauskaitė Nijolė , Darinskas Adas , Jokubauskienė Lina , Characiejus Dainius
Published: February 2014

Background. Antitumor immunotherapy strategies, such as cytokine- based or cell-based immunotherapies, are designed to activate immune response against cancer cells, but considering that malignancy may be associated with the expansion of immunosuppressive components of antitumor immunity, it is likely that in such cases activation of the immune system would further enhance activity of these components, leading to more severe suppression of antitumor immune response thus making more favourable conditions for tumor progression. Materials and methods. We studied the expression of biomarkers, representing immunosuppressive (FOXP3) and cytotoxic (perforin, IFN-γ) CD8highCD57+ T-cell subpopulation functions in the peripheral blood of 34 patients with advanced clear cell renal cell carcinoma (RCC) and 26 controls by multicolour flow cytometry. Results. CD8highCD57+ T cell subpopulation of all CD8+ T cells in RCC patients was significantly higher compared to age-matched healthy controls (p = 0.003). It was found that the mean percentage of suppressive CD8highCD57+FOXP3+ T-cell subset and cytotoxic CD8highCD57+Perforin+ T-cell subset in the CD8highCD57+ T-cell subpopulation was significantly increased in RCC patients compared to controls (p = 0.0004 and p = 0.008, respectively). There was no strong and biologically relevant negative correlation between the expression of FOXP3 and Perforin in the peripheral blood CD8highCD57+ T-cell subpopulation of RCC patients. Conclusions. Subsets of immunosuppressive FOXP3+ T cell and tumor-attacking (cytotoxic) Perforin+ T cells in the CD8highCD57+ T-cell subpopulation are significantly increased in RCC patients compared to controls. These quantitative rearrangements are independent and individual for each RCC patient.
Laparoscopic ovarian transposition in patients with pelvic cancer
Authors: Žilinskas Kastytis , Sabonytė-Balšaitienė Živilė , Samalavičius Narimantas Evaldas
Published: February 2014

Background. The aim of this study was to evaluate the feasibility of laparoscopic ovarian transposition prior to radiation therapy on the preservation of hormonal function in the treatment of pelvic cancer.
Materials and methods. A chart review of premenopausal women diag­nosed with pelvic cancer, who underwent laparoscopic ovarian transposition to paracolic gutters, then received preoperative radiotherapy at the Center of Oncosurgery, Oncology Institute of Vilnius, from January 2010 to July 2013.
Results. A total of 14 patients underwent laparoscopic ovarian transposition. Patients were divided into two groups by localisation of can­cer: 2 (14.29%) patients diagnosed with rectal cancer and 12 (85.71%) with cervical cancer. Patients’ age was from 24 to 42  years with a mean age of 33.71 (SD  ±  5.22) years. The average age of the patients in the first group was 26 (SD ±  2.83) years. In the second group women, aged 29 and 42 years with a mean age of 35 (SD ± 4.35) years, were analyzed. Rectal cancer of stage III was diagnosed in both women of the first group. Tumor stage distribution in the second group, respectively: stage I  –  2  cases (16.67%), stage  II  –  3  cases (25%), stage  III  –  7 cases (58.33%). Seven (58.33%) patients of the second group underwent complete endoscopic staging. In these groups of 14 patients there were 2 (14.3%) complications (injury of the inferior vena cava and postoperative abnormal vaginal bleeding). No postoperative exitus occurred. The mean duration of the operation was 2 hours 26 minutes ± 55 minutes (60–245 minutes), respectively, 2  hours 40  minutes  ±  49  minutes (95–245  minutes) when laparoscopic staging and ovarian transposition was performed and 2  hours 12  minutes  ±  1  hour 1  minute (60–245  minutes) when only ovarian transposition was performed. The hospitalization period ranged from 5 to 52 days (average 12 days).
Conclusions. Laparoscopic ovarian transposition is a relatively safe and effective procedure for preserving ovarian function. This procedure should be considered in all reproductive age female patients who need to undergo pelvic irradiation as part of pelvic cancer treatment.
La sémiologie des odeurs au xixe siècle : du savoir médical à la norme sociale
Authors: Perras Jean-Alexandre , Wicky Érika
Published: February 2014

Si de nombreux médecins appuient encore au xviiie siècle leurs diagnostics sur les odeurs émanant de leurs patients, celles-ci disparaissent progressivement, chassées par le grand mouvement hygiéniste à l’oeuvre au xixe siècle, à l’issue duquel, désormais, c’est l’absence d’odeurs qui garantit non seulement le statut social du sujet, mais aussi sa bonne moralité. En observant l’instauration de normes qui jalonnent ce chemin entre le discours médical et le discours social, telles que celles de la désodorisation et des usages du parfum, il s’agit de faire apparaître l’évolution tout au long du siècle des conceptions et des interprétations de l’identité olfactive.
« Il n’y a pas de mots » et « Ma langue est pleine de mots »
Authors: Bourassa Lucie
Published: February 2014

Christophe Tarkos s’inscrit dans une tradition importante de la modernité littéraire française, où les poètes associent étroitement leur pratique à une méditation sur le langage. Dans des essais et manifestes, il multiplie les déclarations fracassantes, proposant par exemple une vision théorique du signe linguistique (« Le signifiant égale le signifié ») et de la référence (« Le mot n’est pas un référenceur »), des explications étonnantes sur l’origine et la signification du mot « mot », qui « vient du mot mao » et qui « ment » et une théorie d’ensemble sur le langage comme « pâte-mots » ou « Patmo ». Plusieurs commentateurs de l’oeuvre de Tarkos ont commenté cette « pâte-mots », y voyant une métaphore de l’écriture du poète. L’étude qui est proposée ici reviendra abondamment sur cette notion, mais ne l’abordera pas d’abord comme une métaphore apte à expliquer l’ensemble des écrits du poète. La pâte sera appréhendée comme l’un des éléments, central certes, mais non unique, d’une théorie du langage qui se construit en discours, comme un processus, dans l’activité d’écriture. Le but est de mettre au jour certains aspects spécifiques de cette théorie, cela non seulement dans le propos explicite, mais également dans l’organisation du discours, dans son « faire ». L’analyse portera principalement sur des écrits qui thématisent la langue ou la poésie. La méditation de Tarkos sur le langage est multiple, complexe, et non dénuée de paradoxes, si bien que le parcours de la présente étude sera parfois sinueux. Cependant, il sera toujours guidé, plus ou moins visiblement, par l’hypothèse selon laquelle cette théorie, loin d’une pensée du signe et de la séparation, est hantée par le continu.
The oceanic response to mesoscale atmospheric forcing
Authors: Jung Thomas , Serrar Soumia , Wang Qiang
Published: February 2014

The response of the oceanic circulation to mesoscale atmospheric forcing is studied by comparing integrations of a global sea ice‐ocean model with high‐resolution European Centre for Medium‐Range Weather Forecasts analysis data (0.4°) to those with the same forcing coarse grained to a resolution typically employed in climate models and atmospheric reanalyses (1.8°). It is shown that the representation of mesoscale features in atmospheric forcing fields leads to an increase in the strength of the wind‐driven gyres in the North Atlantic and North Pacific regions of about 5–10% of its mean value. An increase of similar magnitude is found for the Atlantic meridional overturning circulation. From the results of this study it is argued that small‐scale atmospheric phenomena such as fronts, mesoscale cyclones, and topographic jets play an important role in driving the mean oceanic circulation.
Photographic observations of streamers and steps in a cloud‐to‐air negative leader
Authors: Edens H. E. , Eack K. B. , Rison W. , Hunyady S. J.
Published: February 2014

A color photograph has been obtained of a negative lightning leader in clear air at 10.3 km altitude. The individual leader steps are resolved as relatively straight segments of at least ~200 m in length, between sharp kinks (nodes) in the channel. Each node is accompanied by a group of streamers of ~100 m in length. One node has an unconnected secondary leader with streamers at both ends. Lightning Mapping Array observations show that the leader was part of an intracloud (IC) flash. The observation shows that steps of negative leaders near 10 km altitude are an order of magnitude longer than values reported in the literature for negative leaders near sea level. Since negative leaders propagate at comparable velocities at low and high altitudes, stepping occurs at a lower rate in IC flashes, which can explain why RF emissions from IC flashes are more intermittent than those from cloud‐to‐ground flashes.
Alaska Megathrust 2: Imaging the megathrust zone and Yakutat/Pacific plate interface in the Alaska subduction zone
Authors: Kim YoungHee , Abers Geoffrey A. , Li Jiyao , Christensen Douglas , Calkins Josh , Rondenay Stéphane
Published: February 2014

We image the slab underneath a 450 km long transect of the Alaska subduction zone to investigate (1) the geometry and velocity structure of the downgoing plate and their relationship to slab seismicity and (2) the interplate coupled zone where the great 1964 earthquake (Mw 9.2) exhibited the largest amount of rupture. The joint teleseismic migration of two array data sets based on receiver functions (RFs) reveals a prominent, shallow‐dipping low‐velocity layer at ~25–30 km depth in southern Alaska. Modeling of RF amplitudes suggests the existence of a thin layer (Vs of ~2.1–2.6 km/s) that is ~20–40% slower than underlying oceanic crustal velocities, and is sandwiched between the subducted slab and the overriding plate. The observed megathrust layer (with Vp/Vs of 1.9–2.3) may be due to a thick sediment input from the trench in combination with elevated pore fluid pressure in the channel. Our image also includes an unusually thick low‐velocity crust subducting with a ~20° dip down to 130 km depth at ~200 km inland beneath central Alaska. The unusual nature of this subducted segment results from the subduction of the Yakutat terrane crust. Our imaged western edge of the Yakutat terrane aligns with the western end of a geodetically locked patch with high slip deficit, and coincides with the boundary of aftershock events from the 1964 earthquake. It appears that this sharp change in the nature of the downgoing plate could control the slip distribution of great earthquakes on this plate interface.
Disfluency Meets Cognitive Load in Multimedia Learning: Does Harder‐to‐Read Mean Better‐to‐Understand?
Authors: Eitel Alexander , Kühl Tim , Scheiter Katharina , Gerjets Peter
Published: February 2014

In a series of four experiments, we examined the impact of disfluency in multimedia learning by testing contrasting predictions derived from disfluency theory and cognitive load theory against each other. Would a less legible text be beneficial to learning when accompanied by pictures, and what would be the role of less legible pictures? Students (N = 308) learned with text and pictures that were either easy‐to‐read (i.e., fluent) or harder‐to‐read (i.e., disfluent) about how a toilet flush works (Experiments 1–3) and about how lightning develops (Experiment 4). In line with disfluency theory, a disfluent text led to better performance in the transfer test and to more invested mental effort in Experiment 1. However, these beneficial effects could not be replicated in Experiments 2, 3, and 4, leaving open questions regarding the stability and generalizability of the disfluency effect, and thus raising concerns regarding its impact for educational practice. Copyright © 2014 John Wiley & Sons, Ltd.
Powder Semi‐Solid Casting Technology for Preparation of High Chromium Cast Iron Alloy
Authors: He Jianjun , Li Xianze
Published: February 2014

A new preparation technology, termed powder semi‐solid (PSS) casting, has been developed for the preparation of fine‐grained alloys. In this process, certain amount of alloy powder, which has the same composition as the melt, is added into the melt and then immediately stirred until the powder is uniformly distributed. The M7C3 carbide phases in the as‐cast alloy are fine batten‐like or in equiaxed shape and their ratio of length to radial reduces. The eutectic colonies are refined greatly comparing with that of the conventionally cast alloys, and their size are between 20 and 50 μm. The α‐Fe transferred from primarily precipitated austenite is refined too. Furthermore, the PSS casting technology can also modify the morphology of austenite grains and refine them effectively.
Borohydride Ionic Liquids and Borane/Ionic‐Liquid Solutions as Hypergolic Fuels with Superior Low Ignition‐Delay Times
Authors: Li Songqing , Gao Haixiang , Shreeve Jean'ne M.
Published: February 2014

In propellant systems, fuels of choice continue to be hydrazine and its derivatives, even though they comprise a class of acutely carcinogenic and toxic substances which exhibit rather high vapor pressures and require expensive handling procedures and costly safety precautions. Hypergolic ionic liquids tend to have low volatility and high thermal and chemical stability, and often exhibit wide liquid ranges, which could allow the use of these substances as bipropellant fuels under a variety of conditions. A new family of borohydride ionic liquids and borane–ionic‐liquid solutions is described which meets nearly all of the desired important criteria for well‐performing fuels. They exhibit ignition‐delay times that are superior to that of any known hypergolic ionic liquid and may thus be legitimate replacements for hydrazine and its derivatives.
Key Lessons from Performance of the U.S. EPA Endocrine Disruptor Screening Program (EDSP) Tier 1 Male and Female Pubertal Assays
Authors: Stump Donald G. , O'Connor John C. , Lewis Joseph M. , Marty M. Sue
Published: February 2014

The male and female pubertal assays, which are included in the U.S. Environmental Protection Agency's (EPA) Endocrine Disruptor Screening Program (EDSP) Tier 1 battery, can detect endocrine‐active compounds operating by various modes of action. This article uses the collective experience of three laboratories to provide information on pubertal assay conduct, interlaboratory reproducibility, endpoint redundancy, and data interpretation. The various criteria used to select the maximum tolerated dose are described. A comparison of historical control data across laboratories confirmed reasonably good interlaboratory reproducibility. With a reliance on apical endpoints, interpretation of pubertal assay effects as specifically endocrine‐mediated or secondary to other systemic effects can be problematic and mode of action may be difficult to discern. Across 21–23 data sets, relative liver weight, a nonspecific endocrine endpoint, was the most commonly affected endpoint in male and female assays. For endocrine endpoints, patterns of effects were generally seen; rarely was an endocrine‐sensitive endpoint affected in isolation. In males, most frequently missed EPA‐established performance criteria included mean weights for kidney and thyroid, and the coefficient of variation for age and body weight at preputial separation, seminal vesicle weight, and final body weight. In females, the frequently missed EPA‐established performance criteria included mean adrenal weight and mean age at vaginal opening. To ensure specificity for endocrine effects, the pubertal assays should be interpreted using a weight‐of‐evidence approach as part of the entire EDSP battery. Based on the frequency with which certain performance criteria were missed, an EPA review of these criteria is warranted.
Engineering the filamentous fungus Neurospora crassa for lipid production from lignocellulosic biomass
Authors: Roche Christine M. , Glass N. Louise , Blanch Harvey W. , Clark Douglas S.
Published: February 2014

Microbially produced triacylglycerol (TAG) is a potential feedstock for the production of biodiesel, but its commercialization will require high yields from low‐cost renewable feedstocks such as lignocellulose. The present study employs a multi‐gene approach to increasing TAG biosynthesis in the filamentous fungus Neurospora crassa. We demonstrate the redirection of carbon flux from glycogen biosynthesis towards fatty acid biosynthesis in a glycogen synthase deletion strain (Δgsy‐1). Furthermore, combining Δgsy‐1 with an enhanced TAG biosynthetic strain (acyl‐Coenzyme A synthase; Δacs‐3) of N. crassa yielded a twofold increase in total fatty acid accumulation over the control strain. The cellulose degrading potential of this double deletion strain was improved by deleting of the carbon catabolite regulation transcription factor (Δcre‐1) to create the triple deletion strain Δacs‐3 Δcre‐1; Δgsy‐1. This strain exhibited early and increased cellulase expression, as well as fourfold increased total fatty acid accumulation over the control on inhibitor‐free model cellulose medium. The Δcre‐1 mutation, however, was not beneficial for total fatty acid accumulation from pretreated lignocellulose. Conversion of dilute‐acid pretreated Miscanthus to TAG was maximum in the constructed strain Δacs‐3; Δgsy‐1, which accumulated 2.3‐fold more total fatty acid than the wild‐type control strain, corresponding to a total fatty acid yield of 37.9 mg/g dry untreated Miscanthus. Biotechnol. Bioeng. 2014;111: 1097–1107. © 2014 Wiley Periodicals, Inc.
Regulating Web Content: The Nexus of Legislation and Performance Standards in the United Kingdom and Norway
Authors: Giannoumis G. Anthony
Published: February 2014

Despite different historical traditions, previous research demonstrates a convergence between regulatory approaches in the United Kingdom and Norway. To understand this convergence, this article examines how different policy traditions influence the legal obligations of performance standards regulating web content for use by persons with disabilities. While convergence has led to similar policy approaches, I argue that national policy traditions have an impact on how governments establish legal obligations for standards compliance. The analysis reveals that national policy traditions influenced antidiscrimination legislation and the capacity and authority of regulatory agencies, which impacted the diverging legal obligations of standards in the United Kingdom and Norway. The analysis further suggests that policy actors mediate the reciprocal influence between national policy traditions and regulatory convergence mechanisms. Copyright © 2014 John Wiley & Sons, Ltd.
Acrolein Oxidation to Acrylic Acid on Mo/V/W‐Mixed Oxide Catalysts
Authors: Drochner Alfons , Kampe Philip , Menning Nadine , Blickhan Nina , Jekewitz Tim , Vogel Herbert
Published: February 2014

Oxidation of acrolein to acrylic acid on Mo/V/W‐mixed oxide catalysts has been studied by means of the isotopic exchange method steady‐state isotopic transient kinetic analysis (SSITKA). As a result of these isotopic exchanges performed with 16O2 and 18O2, some new mechanistic details could be obtained. Acrolein exchanges its oxygen with oxygen of the mixed oxide catalyst. Additionally, the kinetics of the different isotopologues is significantly influenced by oxygen exchange reactions between the surface and the bulk sites. From the SSITKA results, an extended reaction model has been deduced. Thus, the experimentally gained data of the individual isotopologue kinetics could be verified by modeling.
ChemInform Abstract: Direct Hydrolysis Preparation for Novel Bi‐Based Oxysalts Photocatalyst Bi6O5(OH)3 (NO3)5·3H2O with High Photocatalytic Activity.
Authors: He Ying , Zhang Yihe , Huang Hongwei , Tian Na , Luo Yi
Published: February 2014

The title compound is prepared from aqueous Bi(NO3)3·5H2O solutions by sonication for 2 min and further magnetic stirring for 2 h at room temperature.
ChemInform Abstract: Synthesis and Phase Relations of Single‐Phase Fibrous Phosphorus.
Authors: Eckstein Nadine , Hohmann Andrea , Weihrich Richard , Nilges Tom , Schmidt Peer
Published: February 2014

Fibrous phosphorus is prepared by controlled heating of red phosphorus (evacuated silica tube, 1.
ChemInform Abstract: Ion‐Exchange Synthesis, Crystal Structure, and Physical Properties of Hydrogen Titanium Oxide H2Ti3O7.
Authors: Kataoka Kunimitsu , Kijima Norihito , Akimoto Junji
Published: February 2014

The title compound is synthesized from Na2Ti3O7 by Na+/H+ ion exchange in HCl solution at 333 K for 5 d.
ChemInform Abstract: A Mixed‐Addenda Nb/W Polyoxometalate Containing Dimeric Dawson Subunit: Synthesis, Structure, and Characterization.
Authors: Ren Yuanhang , Hu Yichen , Kong Zuping , Gu Min , Yue Bin , He Heyong
Published: February 2014

K4Na4 [H6P2W12Nb4O59 (NbO2)2]2·48H2O is synthesized from an aqueous solution of K12[H2P2W12O48], K7H[Nb6O19], H2O2, and AcOH/AcONa buffer (waterbath, 70 °C, 2 h, 24% yield).
ChemInform Abstract: New Lithium Copper Borates with BO3 Triangles: Li6CuB4O10, Li3CuB3O7, Li8Cu7B14O32, and Li2Cu9B12O28.
Authors: Kuratieva N. V. , Banki M. , Tsirlin A. A. , Eckert J. , Ehrenberg H. , Mikhailova D.
Published: February 2014

The new compounds Li3CuB3O7 (I), Li2Cu9B12O28 (II), and Li8Cu7B14O32 (III) as well as a new polymorph of Li6CuB4O10 (IV) are identified by single crystal XRD after annealing of several compositions of the Li2O—CuO—B2O3 system at 1273 K in air.
ChemInform Abstract: Bicyclic Guanidinium‐Catalyzed Enantioselective Phase‐Transfer Alkylation: Direct Access to Pyrroloindolines and Furoindolines.
Authors: Chen Wenchao , Yang Wenguo , Yan Lin , Tan Choon‐Hong , Jiang Zhiyong
Published: February 2014

The combination of a chiral bicyclic guanidinium salt and zinc iodide is an efficient catalytic system for the enantioselective alkylation of oxindoles (I) and (XI).
ChemInform Abstract: Overriding Effect of Temperature over Reagent and Substrate Size for Boron‐Mediated Aldol Reaction of Methyl Phenylacetate.
Authors: Ramachandran P. Veeraraghavan , Chanda Prem B.
Published: February 2014

The boron‐mediated aldol reaction of methyl phenylacetate with aliphatic and aromatic aldehydes is optimized to give syn‐ or anti‐aldol products.
ChemInform Abstract: Facile Aerobic Photooxidation of Alcohols Using 2‐Chloroanthraquinone under Visible Light Irradiation.
Authors: Shimada Yoshiko , Hattori Kasumi , Tada Norihiro , Miura Tsuyoshi , Itoh Akichika
Published: February 2014

Various catalytic systems are applied in the aerobic photooxidation of primary and secondary alcohols to the corresponding carboxylic acids and ketones under mild conditions.
ChemInform Abstract: Palladium‐Catalyzed Allylic C—H Fluorination.
Authors: Braun Marie‐Gabrielle , Doyle Abigail G.
Published: February 2014

The first catalytic allylic C—H fluorination reaction using a nucleophilic fluoride source is reported.
ChemInform Abstract: Magnetite (Fe3O4) Silica Based Organic—Inorganic Hybrid Copper(II) Nanocatalyst: A Platform for Aerobic N‐Alkylation of Amines.
Authors: Sharma Rakesh K. , Monga Yukti , Puri Aditi , Gaba Garima
Published: February 2014

The applied catalyst can be separated by an external magnet and reused several times.
ChemInform Abstract: Asymmetric Aldol Reactions Between Acetone and Benzaldehydes Catalyzed by Chiral Zn2+ Complexes of Aminoacyl 1,4,7,10‐Tetraazacyclododecane: Fine‐Tuning of the Amino‐Acid Side Chains and a Revised Reaction Mechanism.
Authors: Itoh Susumu , Tokunaga Takuya , Sonoike Shotaro , Kitamura Masanori , Yamano Akihito , Aoki Shin
Published: February 2014

The yields and enantioselectivities of the reaction are improved compared to the known methods.
ChemInform Abstract: Synthesis of 2‐Substituted 9,10‐Anthraquinones.
Authors: Chang Meng‐Yang , Tai Hang‐Yi
Published: February 2014

Racemic 2‐triazolyl or 2‐alkylethyl 9,10‐anthraquinone derivatives [(V), (X), and (XI)] are efficiently synthesized in good yields by a three‐ or four‐step procedure involving bromination, nucleophilic substitution, and CuI‐promoted 1,3‐dipolar cycloaddition or alkylation and reductive desulfonylation, respectively.
ChemInform Abstract: Oxidation of Sulfides with Hydrogen Peroxide Catalyzed by Vitamin B2 Derivatives.
Authors: Imada Yasushi , Takagishi Masamitsu , Komiya Naruyoshi , Naota Takeshi
Published: February 2014

5‐Ethyl‐3‐methyl‐2′,4′:3′,5′‐di‐O‐methyleneriboflavinium perchlorate, readily available from commercially available riboflavin (vitamin B2), acts as an highly efficient and robust organocatalyst for the selective oxidation of organic sulfides to corresponding sulfoxides (11 examples) under mild conditions.
ChemInform Abstract: Metal‐Free Arylations via Photochemical Activation of the Ar—OSO2R Bond in Aryl Nonaflates.
Authors: Raviola Carlotta , Canevari Veronica , Protti Stefano , Albini Angelo , Fagnoni Maurizio
Published: February 2014

The reaction can be carried out using the premade ArOSO2Nf or the reagents can be made in situ.
ChemInform Abstract: Catalyst‐Controlled Highly Selective Coupling and Oxygenation of Olefins: A Direct Approach to Alcohols, Ketones, and Diketones.
Authors: Su Yijin , Sun Xiang , Wu Guolin , Jiao Ning
Published: February 2014

A method for the direct synthesis of substituted alcohols, ketones, and diketones through a catalyst‐controlled highly chemoselective coupling and oxygenation of olefins is developed.
ChemInform Abstract: Stereoselective Synthesis of Benzofulvenes via a Palladium‐Catalyzed Cyclization of 1,3‐Dienes Derived from Morita—Baylis—Hillman Adducts.
Authors: Lim Cheol Hee , Kim Ko Hoon , Lim Jin Woo , Kim Jae Nyoung
Published: February 2014

A facile synthesis of benzofulvenes is carried out via Pd‐catalyzed intramolecular Mizoroki—Heck reaction of 1,3‐dienes easily obtained from the Wittig reaction between Morita—Baylis—Hillman adducts and various aldehydes (not shown).
ChemInform Abstract: Pt‐Catalyzed C—C Activation Induced by C—H Activation.
Authors: Bowring Miriam A. , Bergman Robert G. , Tilley T. Don
Published: February 2014

The unusual rearrangement product pentahydroindene (II) is generated in good yield in the presence of a platinum catalyst.
ChemInform Abstract: Synthesis and Characterization of Novel Aryl Cyclitols: Polycyclitols.
Authors: Balci Neslihan , Anil Baris , Kelebekli Latif , Sahin Ertan , Goeksu Sueleyman
Published: February 2014

A new triol and a pentol are synthesized starting from the Diels—Alder adduct (III) via stereoselective reduction of the ketone groups in (III) and subsequent cis‐dihydroxylation, respectively.
ChemInform Abstract: Molecular Diversity from Aromatics. A Tandem Oxidative Dearomatization, Cycloaddition and Reactivity Modulation in Excited States: Synthesis of Tricyclo[5.3.1.01,5]undecanes and Bicyclo[4.2.0]octanes from Common Precursors.
Authors: Singh Vishwakarma , Islam Sk. Nurul , Mali Jyotirling
Published: February 2014

Oxidation of the hydroxymethylphenol (I) generates a dearomatized 6,6‐spiroepoxycyclohexa‐2,4‐dienone intermediate which is trapped by Diels—Alder reaction with acrylates.
ChemInform Abstract: Organocatalyzed Asymmetric Synthesis of Dihydrodibenzofurans Based on a Dienamine Process.
Authors: Wang Zi‐Yu , Wong Wing‐Tak , Yang Dan
Published: February 2014

The first organocatalyzed asymmetric method for the synthesis of dihydrodibenzofurans works well with a broad range of substrates and gives only the cis‐diastereomers in good yields with up to 91% ee.
ChemInform Abstract: Photochemical Double 5‐exo Cyclization of Alkenyl‐Substituted Dithienylacetylenes: Efficient Synthesis of Diarylated Dithienofulvalenes.
Authors: Fukazawa Aiko , Karasawa Takashi , Zhang Hongyu , Minemura Kazumitsu , Camacho Cristopher , Wang Jian , Irle Stephan , Yamaguchi Shigehiro
Published: February 2014

A new photochemical cyclization of bis(alkenylthienyl)acetylenes (I) is presented as an efficient method to synthesize diaryl‐substituted dithienofulvalenes (II).