bluuebunny/crossref_metadata_2025 huggingface dataset:
Convectively injected water vapor in the North American summer lowermost stratosphere
Authors: Schwartz Michael J. , Read William G. , Santee Michelle L. , Livesey Nathaniel J. , Froidevaux Lucien , Lambert Alyn , Manney Gloria L.
Published: March 2013

Anderson et al. (2012) (A2012) report in situ observations of convectively injected water vapor (H2O) in the North American (NA) summer lowermost stratosphere (LMS), occasionally exceeding 12ppmv. They contend that, in such cold/wet conditions, heterogeneous chemistry on binary water‒sulfate aerosols can activate chlorine, leading to catalytic ozone destruction. Aura Microwave Limb Sounder 100 hPa and 82.5 hPa H2O measurements show that, indeed, the NA LMS is unusually wet, both in mean values and in outliers reaching 18ppmv. Using A2012's threshold, 4% (0.03%) of 100 hPa (82.5 hPa) NA July–August observations are cold/wet enough for activation. Cold parcels, whether wet or dry, typically have much less HCl to activate and O3to destroy than A2012's initial conditions. Slightly lower concentrations of HCl and O3 in cold/wet parcels are attributable, at least in part, to dilution by tropospheric air. Alarming reductions in NA summer column O3suggested by A2012 are not seen in the current climate.
Heat transport through diffusive interfaces
Authors: Flanagan Jason D. , Lefler Angela S. , Radko Timour
Published: April 2013

We perform a series of 3‐D Direct Numerical Simulations (DNS) to assess the vertical heat transport through thermohaline staircases in the Arctic Ocean. The diagnostics of DNS, performed for the first time in the realistic parameter range, result in vertical fluxes exceeding those of extant “four‐thirds flux laws” by as much as a factor of 2 and suggest that the 4/3 exponent may require downward revision. Through a series of equivalent 2‐D DNS, we show that they are consistent with their more resource‐intensive 3‐D counterparts for sufficiently large density ratio (Rρ) but underestimate heat transport for low Rρ. Finally, we examine the role of boundary conditions in controlling the vertical heat transport. Rigid boundaries—a necessary ingredient in laboratory‐derived flux‐laws—are shown to reduce the estimates of heat fluxes relative to the corresponding periodic boundary conditions.
The cancer‐testis antigen BORIS phenocopies the tumor suppressor CTCF in normal and neoplastic cells
Authors: Tiffen Jessamy C. , Bailey Charles G. , Marshall Amy D. , Metierre Cynthia , Feng Yue , Wang Qian , Watson Sarah L. , Holst Jeff , Rasko John E.J.
Published: March 2013

BORIS and CTCF are paralogous, multivalent 11‐zinc finger transcription factors that play important roles in organizing higher‐order chromatin architecture. BORIS is a cancer‐testis antigen with a poorly defined function in cancer, although it has been hypothesized to exhibit oncogenic properties. CTCF, however, has been postulated as a candidate tumor suppressor. We collated the genetic lesions in BORIS and CTCF from multiple cancers identified using high‐throughput genomics. In BORIS, nonsense and missense mutations are evenly distributed. In CTCF, recurrent mutations are mostly clustered in the conserved zinc finger domain and at residues critical for contacting DNA and zinc ion co‐ordination. Three missense mutations are common to both proteins. We used an inducible lentivector to express wildtype BORIS or CTCF in primary cells and cancer cell lines in order to define their functional differences. Both BORIS and CTCF caused a significant decrease in cell proliferation and clonogenic capacity, without alteration of specific cell cycle phases. Both BORIS and CTCF conferred protective effects in primary cells and some cancer cells during UV damage‐induced apoptosis. Using a bioluminescent MCF‐7 orthotopic breast cancer model in vivo, we demonstrated that CTCF and BORIS suppressed breast cancer growth. These findings provide further evidence that CTCF behaves as a tumor suppressor, and show BORIS has a similar growth inhibitory effect in vitro and in vivo. Hence, acquired zinc finger mutations may disrupt these functions, thereby contributing to tumor growth and development.
Micro(RNA)managing Endoplasmic Reticulum Stress
Authors: Byrd Andrew E. , Brewer Joseph W.
Published: April 2013

Cellular disturbances that cause accumulation of misfolded proteins in the endoplasmic reticulum (ER) lead to a condition referred to as “ER stress” and trigger the unfolded protein response (UPR), a signaling pathway that attempts to restore ER homeostasis. The complexity of UPR signaling can generate adaptive and apoptotic outputs, depending on the nature and duration of the ER stress. MicroRNAs (miRNAs), small non‐coding RNAs that typically repress gene expression, have recently emerged as key gene regulators of the proadaptive/proapoptotic molecular switch emanating from the ER. Importantly, select miRNAs have been shown to directly regulate key UPR components. © 2013 IUBMB Life, 65(5):373–381, 2013.
The chalcone 2′‐hydroxy‐4′,5′‐dimethoxychalcone activates death receptor 5 pathway and leads to apoptosis in human nonsmall cell lung cancer cells
Authors: Yang Lina , Su Ling , Cao Congmei , Xu Linyan , Zhong Diansheng , Xu Lijia , Liu Xiangguo
Published: April 2013

Natural chalcones have been proved to inhibit cancer cells with therapeutic potential, but the underlying molecular mechanism is still largely unexplored. Here, we identified a novel chalcone, 2′‐hydroxy‐4′,5′‐dimethoxychalcone (HDMC) and demonstrated that HDMC induced apoptosis in various nonsmall cell lung cancer cells. Further study showed that HDMC elevated cellular reactive oxygen species (ROS) levels, thus inducing expressions of ATF4 and C/EBP homologous protein (CHOP). Then, death receptor 5 (DR5) was upregulated through ATF4–CHOP axis and eventually resulted in apoptosis. We also found that downregulation of c‐FLIPL contributed to HDMC‐induced apoptosis. In conclusion, HDMC induces apoptosis in human nonsmall cell lung cancer cells via activation of DR5 signaling pathway, and ROS‐mediated ATF4–CHOP axis is involved in the process. Our results further supported the potential for HDMC to be developed as a new antitumor agent for cancer therapy or chemoprevention. © 2013 IUBMB Life, 65(6):533–543, 2013
Enzymatic activity of Cydia pomonella larvae reared on diets produced with agro‐industrial hydrolyzed wastes
Authors: Gnepe Jean Robert , Tyagi Rajeshwar Dayal , Brar Satinder Kaur , Valéro José R. , Surampalli Rao Y.
Published: March 2013

BACKGROUND

This study compared the physical‐chemical characteristics and the nutrient potential of brewery wastewater (BWW) and apple juice industry sludge referred to as pomace (POM). The use of these wastes as alternative nutrients by replacing the standard components (soya flour, wheat germ and yeast extract) allowed production of a balanced diet for rearing codling moth (CM) larvae.

RESULTS

The hydrolysis pretreatment (100 °C/30 min) contributed to enhancing the nutritive potential (almost 600%) and improved the viscosity (decreased from 770.5 to 435 mPa s for BWW and from 460 to 383 mPa s for POM) of the waste. The BWWH+SF diet supplied higher assimilated nutrients (2.071 mg proteins, 2.274 mg carbohydrates and 0.974 mg lipids) showing higher breeding efficiency (93% hatching, 85% larvae, 76% cocoon and 70% adults). Furthermore, the results of the larvae breeding on BWWH+SF diet was the best which for the enzymatic activity (59.7 UI mL‐1 protease, 2.9 mg L−1 amylase and 1.93 U mg−1 lipase), consumption rates of proteins (451.79 mg kg−1), carbohydrates (396.43 mg kg−1) and lipids (91.07 mg kg−1) consumed on these diets.

CONCLUSIONS

BWWH+SF was the best diet with respect to enzymatic activity, consumption of nutrients and larval breeding efficiency compared with POMH+SF and the standard diet. © 2013 Society of Chemical Industry
Nitrite as oxidizing power for p‐cresol removal using a denitrifying sludge: kinetic study
Authors: González‐Blanco Gehovana , Cuervo‐López Flor , Cervantes Francisco J. , Beristain‐Cardoso Ricardo , Gómez Jorge
Published: March 2013

Background

Chemical plants, oil refineries and petrochemical plants discharge wastewaters polluted with phenolic and nitrogen compounds. Denitrification is an economical and feasible process, however, metabolic and kinetic information is required in order to know and to control the limitations involved when nitrite is present or accumulated. The goal of this study was to study the kinetic behavior of a denitrifying sludge and to reduce nitrite at several p‐cresol‐C (p‐Cr) concentrations.

Results

Over the 10 to 45 mg p‐Cr L−1 concentration range tested, nitrite reduction was linked to p‐Cr oxidation and the specific rate increased to 7.02 mg NO2−‐N g−1 VSS h, with CO2 and N2 the products. At higher initial p‐Cr concentrations, inhibition was observed, diminishing the specific rate to 1.60 mg NO2−‐N g−1 VSS h. Electron balance showed that p‐Cr consumption was carried out by two biological processes; denitrification and fermentation. The kinetic profile followed the Haldane model, with inhibition constant (Ki) of 35.75 mg p‐Cr L−1, affinity constant (Ks) of 20.32 mg p‐Cr L−1 and maximum specific nitrite reduction (qmax) of 9.48 mg NO2−‐N g−1 VSS h.

CONCLUSIONS

The results suggest that p‐cresol can be removed by denitrification and fermentation. Kinetic information should be considered for designing and operating denitrifying reactors to treat industrial wastewaters containing phenolic compounds and nitrite. © 2013 Society of Chemical Industry
Action research in radiography: What it is and how it can be conducted
Authors: Munn Zachary , Pearson Alan , Jordan Zoe , Murphy Frederick , Pilkington Diana
Published: April 2013

Action research is a form of research that investigates and describes a social or work situation with the aim of achieving a change which results in improvement. This article emphasizes the potential for action research to be a useful research method in radiography. A search was conducted to determine the extent to which action research has been utilized in radiography. Although action research has been used in a number of health‐care settings, there are no published examples of action research being utilized in a clinical medical imaging department. Action research is discussed in detail, along with an example guide for an action research study. Action research has been identified as a useful way to affect change, to involve radiographers in the research process, and to introduce evidence‐based practice to radiography.
Multivariate analysis of combined Raman and fibre‐optic reflectance spectra for the identification of binder materials in simulated medieval paints
Authors: Pallipurath Anuradha , Skelton Jonathan , Ricciardi Paola , Bucklow Spike , Elliott Stephen
Published: April 2013

The non‐invasive identification of paint materials used in works of art is essential, both for preserving and restoring them, and also for understanding and verifying the history surrounding their creation. As such, the development of suitable non‐invasive techniques has received much interest in recent years. We have investigated the use of Fourier transform (FT)‐Raman spectroscopy and fibre‐optic reflectance spectroscopy (FORS), together with multivariate principal‐component analysis (PCA) techniques, in order to identify the pigment and binding materials used in made‐up samples representative of real artwork. We demonstrate that both types of spectroscopy provide complementary information which can be used to identify the pigments and binders in paint samples. We show that PCA with FT‐Raman spectra can be used to assist in the identification of oil‐based binders, and that the additional data provided by FORS spectra enables PCA on combined spectra to identify more complex proteinaceious and polysaccharide‐based binding media. The results presented here demonstrate that multivariate analyses of lead‐based paints, using data measured by FT‐Raman and FORS in conjunction, have much potential for identifying individual pigments and binders in paint samples. This provides a path towards computer‐assisted characterisation of paint materials on artwork. Copyright © 2013 John Wiley & Sons, Ltd.
The confounding effect of cryptic relatedness for environmental risks of systolic blood pressure on cohort studies
Authors: Shibata Kyoko , Hozawa Atsushi , Tamiya Gen , Ueki Masao , Nakamura Tomohiro , Narimatsu Hiroto , Kubota Isao , Ueno Yoshiyuki , Kato Takeo , Yamashita Hidetoshi , Fukao Akira , Kayama Takamasa ,   Yamagata University Genomic Cohort Consortium
Published: April 2013

The impact of cryptic relatedness (CR) on genomic association studies is well studied and known to inflate false‐positive rates as reported by several groups. In contrast, conventional epidemiological studies for environmental risks, the confounding effect of CR is still uninvestigated. In this study, we investigated the confounding effect of unadjusted CR among a rural cohort in the relationship between environmental risk factors (body mass index, smoking status, alcohol consumption) and systolic blood pressure. We applied the methods of population‐based whole‐genome association studies for the analysis of the genome‐wide single nucleotide polymorphism data in 1622 subjects, and detected 20.2% CR in this cohort population. In the case of the sample size, approximately 1000, the ratio of CR to the population was 20.2%, the population prevalence 25%, the prevalence in the CR 26%, heritability for liability 14.3% and prevalence in the subpopulation without CR 26%, the difference of estimated regression coefficient between samples with and without CR was not significant (P‐value = 0.55). On the other hand, in another case with approximately >20% heritability for liability, we showed that confounding due to CR biased the estimation of exposure effects.
A calibration‐based approach to real‐time in vivo monitoring of pyruvate C1 and C2 polarization using the JCC spectral asymmetry
Authors: Lau Justin Y. C. , Chen Albert P. , Gu Yi‐Ping , Cunningham Charles H.
Published: April 2013

A calibration‐based technique for real‐time measurement of pyruvate polarization by partial integral analysis of the doublet from the neighbouring J‐coupled carbon is presented. In vitro calibration data relating the C2 and C1 asymmetries to the instantaneous C1 and C2 polarizations, respectively, were acquired in blood. The feasibility of using the in vitro calibration data to determine the instantaneous in vivo C1 and C2 polarizations was demonstrated in the analysis of rat kidney and pig heart spectral data. An approach for incorporating this technique into in vivo protocols is proposed. Copyright © 2013 John Wiley & Sons, Ltd.
Nanoinduced morphology and enhanced properties of epoxy containing tungsten disulfide nanoparticles
Authors: Shneider Mark , Dodiuk Hanna , Tenne Reshef , Kenig Shmuel
Published: March 2013

Closed‐cage (fullerene‐like) nanoparticles (NPs) of WS2 are currently produced in large amounts and were investigated as additives to thermoplastics and thermosetting polymers. The nanoinduced morphology and the resulting enhanced fracture toughness of epoxy/WS2 nanocomposites were studied. The morphology of the epoxy nanocomposites was induced by controlled WS2 surface chemistry. The WS2 NPs used were either untreated or chemically treated with acryloxy, which is compatible, and alkyl silane, which is incompatible, respectively, with the epoxy matrix. In the case where the acryloxy silane was used to treat the WS2 particles, good dispersion and compatibility were obtained in the epoxy resin. Moreover, a distinct nodular morphology was induced on fracture as a result of nucleation by the compatible NPs. In the case where the alkyl silane treatment was used cavitation morphology was induced, following mechanical loading, which is the result of incompatibility with the epoxy resin. The fracture toughness results showed an increase of 70% for nanocomposites contains alkyl‐treated WS2 compared with the neat epoxy. Modeling of the nodular morphology enabled the determination of optimal concentration of the WS2 in epoxy (0.3% by weight). Two main fracture mechanisms were observed, crack bowing around the nodular boundaries in the case of compatibility between the nanoparticle and the epoxy and particle‐induced cavitation in the case of incompatibility, respectively. These results are of significant importance both for epoxy‐based adhesives and fiber composites. POLYM. ENG. SCI., 53:2624–2632, 2013. © 2013 Society of Plastics Engineers
Morphology and properties of poly(benzoxazine‐co‐urethane)s based on bisphenol‐S/aniline benzoxazine
Authors: Li Zhihong , Liu Yanfang , Zhang Jie , Zhao Shasha , Luo Shanshan , Yue Zaiqin , Run Mingtao
Published: March 2013

Poly(benzoxazine‐co‐urethane) was prepared by melt‐blending bisphenol‐S/aniline‐type benzoxazine (BS‐a) with isocyanate‐terminated polyurethane (PU) prepolymer based on 2,4‐toluene diisocyanate and poly(ethylene glycol), followed by thermally activated polymerization of the blend. The copolymerization reaction between BS‐a and PU prepolymer was monitored using Fourier transform infrared spectroscopy. The morphology, dynamic mechanical properties, and thermal stability of the poly(benzoxazine‐co‐urethane) were studied using scanning electron microscopy, dynamic mechanical analysis, and thermogravimetry. Homogeneous morphology is shown in scanning electron micrographs of the fracture surfaces of poly(benzoxazine‐co‐urethane)s with different urethane weight fractions, and the roughness of the surface increases with urethane content increasing. Correspondingly, a single glass transition temperature (Tg) is shown on the dynamic mechanical analysis curves of the poly(benzoxazine‐co‐urethane)s, and the Tg is higher than that of the polybenzoxazine. With increase in the urethane content, the Tg and water absorption of poly(benzoxazine‐co‐urethane) increase, whereas the storage modulus and thermal stability decrease. POLYM. ENG. SCI., 53:2633–2639, 2013. © 2013 Society of Plastics Engineers
Crystal structures of Klebsiella pneumoniae pantothenate kinase in complex with N‐substituted pantothenamides
Authors: Li Buren , Tempel Wolfram , Smil David , Bolshan Yuri , Schapira Matthieu , Park Hee‐Won
Published: March 2013

N‐Substituted pantothenamides are derivatives of pantothenate, the precursor in the biosynthesis of the essential metabolic cofactor coenzyme A (CoA). These compounds are substrates of pantothenate kinase (PanK) in the first step of CoA biosynthesis and possess antimicrobial activity against various pathogenic bacteria. Here we solved the crystal structure of the Klebsiella pneumoniae PanK (KpPanK) in complex with N‐pentylpantothenamide (N5‐Pan) to understand the molecular basis of its antimicrobial activity. The structure reveals a polar pocket interacting with the pantothenate moiety of N5‐Pan and an aromatic pocket loosely protecting the pentyl tail, suggesting that the introduction of an aromatic ring to a new pantothenamide may enhance the compound's affinity to KpPanK. To test this idea, we synthesized N‐pyridin‐3‐ylmethylpantothenamide (Np‐Pan) and solved its co‐crystal structure with KpPanK. The structure reveals two alternat conformations of the aromatic ring of Np‐Pan bound at the aromatic pocket, providing the basis for further improvement of pantothenamide binding to KpPanK. Proteins 2013; 81:1466–1472. © 2013 Wiley Periodicals, Inc.
Crystal structure of the invertebrate bifunctional purine biosynthesis enzyme PAICS at 2.8 Å resolution
Authors: Taschner Michael , Basquin Jérôme , Benda Christian , Lorentzen Esben
Published: April 2013

Two important steps of the de novo purine biosynthesis pathway are catalyzed by the 5‐aminoimidazole ribonucleotide carboxylase and the 4‐(N‐succinylcarboxamide)‐5‐aminoimidazole ribonucleotide synthetase enzymes. In most eukaryotic organisms, these two activities are present in the bifunctional enzyme complex known as PAICS. We have determined the 2.8‐Å resolution crystal structure of the 350‐kDa invertebrate PAICS from insect cells (Trichoplusia ni) using single‐wavelength anomalous dispersion methods. Comparison of insect PAICS to human and prokaryotic homologs provides insights into substrate binding and reveals a highly conserved enzymatic framework across divergent species. Proteins 2013; 81:1473–1478. © 2013 Wiley Periodicals, Inc.
A jamming‐attack‐defending data forwarding scheme based on channel surfing in wireless sensor networks
Authors: Ghosal Amrita , Bit Sipra Das
Published: April 2013

Wireless sensor networks (WSNs) are susceptible to various attacks, and these attacks pose a major threat to the normal functioning of WSNs. Jamming is one such attack, which affects network operations by blocking frequencies. Hence, the need of defending such attack is of utmost importance. This paper proposes three variants of a data forwarding scheme using multi‐level multi‐tier architecture, which employs judicious surfing of a pair of channels to defend jamming attack in WSNs. Variant I defends the attack at the cost of an affordable delay. Improvement of the scheme in minimizing data transmission time is made in variant II. Further improvement in transmission time is made in variant III and is made more realistic by introducing sensing capability at all tiers, thereby increasing network coverage. Simulation is performed to establish each of the successor's variant's improvement over its predecessor. The performance of the scheme in terms of area coverage, packet delivery ratio, and control message overhead is compared with an existing jamming‐defending scheme for infrastructure‐based wireless network. Finally, comparison results establish that although the proposed scheme is equivalent to its infrastructure‐based counterpart in terms of coverage, it provides a more lightweight solution and maintains improved performance in terms of packet delivery ratio. Copyright © 2013 John Wiley & Sons, Ltd.
Planning and evaluating clinical trials with composite time‐to‐first‐event endpoints in a competing risk framework
Authors: Rauch G. , Beyersmann J.
Published: April 2013

Composite endpoints combine several events of interest within a single variable. These are often time‐to‐first‐event data, which are analyzed via survival analysis techniques. To demonstrate the significance of an overall clinical benefit, it is sufficient to assess the test problem formulated for the composite. However, the effect observed for the composite does not necessarily reflect the effects for the components. Therefore, it would be desirable that the sample size for clinical trials using composite endpoints provides enough power not only to detect a clinically relevant superiority for the composite but also to address the components in an adequate way. The single components of a composite endpoint assessed as time‐to‐first‐event define competing risks. We consider multiple test problems based on the cause‐specific hazards of competing events to address the problem of analyzing both a composite endpoint and its components. Thereby, we use sequentially rejective test procedures to reduce the power loss to a minimum. We show how to calculate the sample size for the given multiple test problem by using a simply applicable simulation tool in SAS. Our ideas are illustrated by two clinical study examples. Copyright © 2013 John Wiley & Sons, Ltd.
Streaming Media Advertising: An Empirical Study
Authors: Shan Siqing , Mao Zhonghui , Zhou Ronggang , Liu Zhilian , Wu Feng
Published: April 2013

This study utilized the eye‐tracking technology to investigate consumers' behavioral responses in three different streaming media advertising forms. Thirty‐two undergraduates and postgraduates participated in this study, and their eye‐movement data were collected as they viewed four different types of streaming media advertisements on Web pages coded in Chinese. Considering audiences' online status, both browsing scenario and information search scenario are designed. Through analysing the impact of advertisement forms on audience by using the two‐way analysis of variance, the results show that (i) audiences are more sensitive to streaming media advertising when they are in the information search scenario; (ii) ordinary floating layer advertising and Tear Page Advertising capture more attention than iTouch and hurdles advertising; and (iii) the play time do affect audiences' response to streaming media advertising. Detailed discussions on results and suggestions for future studies are provided in this paper. Copyright © 2013 John Wiley & Sons, Ltd.
Kran‐ und Baumaschinenmuseum: Von der Idee zur Wirklichkeit
Authors: Moeller Dirk P.
Published: April 2013

Im Zusammenhang mit der Planung der vorliegenden Ausgabe nahm der Chefredakteur von STAHLBAU, Dr.‐Ing. Karl‐Eugen Kurrer, Kontakt mit der AG Kran‐ und Baumaschinenmuseum e.V. auf und bat Herrn Dirk P. Moeller um eine Schilderung der Entstehungsgeschichte des Kran‐ und Baumaschinenmuseums (KBM) aus persönlicher Sicht.
A subtraction scheme for computing QCD jet cross sections at NNLO: integrating the doubly unresolved subtraction terms
Authors: Somogyi Gábor
Published: April 2013

Abstract

We finish the definition of a subtraction scheme for computing NNLO corrections to QCD jet cross sections. In particular, we perform the integration of the soft-type contributions to the doubly unresolved counterterms via the method of Mellin-Barnes representations. With these final ingredients in place, the definition of the scheme is complete and the computation of fully differential rates for electron-positron annihilation into two and three jets at NNLO accuracy becomes feasible.
-recurrence in skew products
Authors: CHAIKA JON , RALSTON DAVID
Published: April 2013

The rate of recurrence to measurable subsets in a conservative, ergodic infinite-measure-preserving system is quantified by generic divergence or convergence of certain sums given by a function $\omega (n)$. In the context of skew products over transformations of a probability space, we relate this notion to the more frequently studied question of the growth rate of ergodic sums (including Lyapunov exponents). We study in particular skew products over an irrational rotation given by bounded variation $ \mathbb{Z} $-valued functions: first the generic situation is studied and recurrence quantified, and then certain specific skew products over rotations are shown to violate this generic rate of recurrence.
Attractive regular stochastic chains: perfect simulation and phase transition
Authors: GALLO SANDRO , TAKAHASHI DANIEL Y.
Published: April 2013

We prove that uniqueness of the stationary chain, or equivalently, of the$g$-measure, compatible with an attractive regular probability kernel is equivalent to either one of the following two assertions for this chain: (1) it is a finitary coding of an independent and identically distributed (i.i.d.) process with countable alphabet; (2) the concentration of measure holds at exponential rate. We show in particular that if a stationary chain is uniquely defined by a kernel that is continuous and attractive, then this chain can be sampled using a coupling-from-the-past algorithm. For the original Bramson–Kalikow model we further prove that there exists a unique compatible chain if and only if the chain is a finitary coding of a finite alphabet i.i.d. process. Finally, we obtain some partial results on conditions for phase transition for general chains of infinite order.
Frontier as Resource: Law, Crime, and Sovereignty on the Margins of Empire
Authors: Beverley Eric Lewis
Published: April 2013

Nineteenth-century European colonialism produced a textured and uneven legal terrain rather than homogeneous imperial units. The fragmentation of sovereignty between empires and subordinated states created frontier zones that unsettled the workings of governance. This article views the developing landscape of power in high colonial South Asia from the loosely controlled frontier zone between Hyderabad, a Princely State ruled by sovereign Muslim dynasts titled Nizams, and the Bombay Presidency, part of Britain's Indian Empire, or Raj. I argue that the heterogeneous legal terrain along the border was a useful resource for administrators and subjects. State officials of both Hyderabad and Bombay justified various projects there; subjects of the two states shopped forums in a legal pluralist environment; and populations on either side of the border whose livelihoods and political agendas ran afoul of social pressures or the economic and cultural imperatives of state projects fled there from adversity. I examine cases of alleged cattle rustlers, bandits, and prostitutes and their engagements with police and courts to explore the political challenges and possibilities the frontier offered different groups. Colonial attempts to extend racialized policing practices across the frontier were frequently met by machinations of marginal people trying to avoid imprisonment or extricate themselves from oppressive social structures. Such figures could use the ambiguity of frontier legal authority to their advantage. The picture that emerges is one of a brute and often-arbitrary colonial power offset by alternative malleable sovereignties that resourceful subjects could play against one another.
On the classification of the real vector subspaces of a quaternionic vector space
Authors: Pantilie Radu
Published: April 2013

We prove the classification of the real vector subspaces of a quaternionic vector space by using a covariant functor which associates, to any pair formed of a quaternionic vector space and a real subspace, a coherent sheaf over the sphere.
Topological criteria for schlichtness
Authors: Teitler Zach
Published: April 2013

We give two sufficient criteria for schlichtness of envelopes of holomorphy in terms of topology. These are weakened converses of results of Kerner and Royden. Our first criterion generalizes a result of Hammond in dimension 2. Along the way, we also prove a generalization of Royden's theorem.
Unique microbiology of chronically unstable canal wall down tympanomastoid cavities: considerations for surgical revision
Authors: Gluth M B , Tan B Y B , Santa Maria P L , Atlas M D
Published: April 2013

Objective:

To review the microbiology of open tympanomastoid cavities in patients who underwent revision surgery due to chronic instability.

Methods:

This paper describes a retrospective chart review of surgical revision cases of chronically unstable open mastoid cavities. Patient records from 2000 to 2010 were reviewed for the type of organism cultured, antimicrobial resistance and the presence of cholesteatoma.

Results:

In total, 121 revision surgical procedures were performed on 101 patients. Seventy-nine procedures involved culture specimen processing, 37 of which were positive. The most commonly cultured organism wasStaphylococcus aureus,which was more than twice as common as any other pathogen. The presence of cholesteatoma had no impact on the likelihood of a positive culture or polymicrobial culture. Antimicrobial-resistant pathogens were uncommon.

Conclusion:

A positive culture was not an overwhelmingly common characteristic of unstable tympanomastoid cavities. Furthermore, antimicrobial resistance did not appear to play an essential role in leading patients towards revision open mastoid surgery.
The architecture ofit-clefts
Authors: HAEGEMAN LILIANE , MEINUNGER ANDRÉ , VERCAUTEREN ALEKSANDRA
Published: April 2013

This paper examines quasi-monoclausal left-peripheral analyses of Englishit-clefts. Though attractive because such analyses bring out commonalities betweenit-clefts on the one hand and focus fronting andwh-questions on the other, the range of word order variations available in Englishit-clefts reveals that such monoclausal analyses ofit-clefts lead to considerable complications of implementation, ultimately undoing the gain in terms of economy that initially would seem to justify them. In particular, we will show that, on closer inspection, the presumed focus fronting init-clefts cannot be targeting the position deployed for ‘regular’ left-peripheral focus fronting. Moreover, both implementations of the monoclausal analysis discussed make the wrong predictions with respect to the distribution ofit-clefts. In particular, as already argued by Hooper & Thompson (1973) and Emonds (1976), Englishit-clefting, unlike ‘regular’ focus fronting, is not a main clause phenomenon. Given these objections, we conclude that the left-peripheral analyses ofit-clefts are ill-founded.
On the excitation of higher harmonic electrostatic dust cyclotron waves
Authors: ROSENBERG M.
Published: April 2013

In a magnetized plasma containing charged dust whose motion is magnetized, one of the fundamental collective modes that could occur is the electrostatic dust cyclotron (EDC) wave with frequency near the dust cyclotron frequency. The EDC wave propagates nearly perpendicular to the magnetic field with a small parallel wave number, so that it can be driven unstable by ion flow along the magnetic field. Because unstable parallel wavelengths can be relatively large, this places constraints on the plasma device size. In this paper, we use linear kinetic theory to investigate the excitation of higher harmonic EDC waves that have wavelengths smaller than that of the fundamental mode. Collisions of charged particles with neutrals and Coulomb collisions including dust–dust collisions are taken into account. Constraints on possible parameter ranges arising from collisional effects or from requiring stability of other waves are discussed. Numerical results are presented for possible sets of laboratory dusty plasma parameters.
Relativistic collisionless shocks formation in pair plasmas
Authors: BRET ANTOINE , STOCKEM A. , FIUZA F. , RUYER C. , GREMILLET L. , NARAYAN R. , SILVA L. O.
Published: April 2013

Collisionless shocks are ubiquitous in astrophysics and in the laboratory. Recent numerical simulations and experiments have shown how these can arise from the encounter of two collisionless plasma shells. When the shells interpenetrate, the overlapping region turns unstable, triggering the shock formation. As a first step toward a microscopic understanding of the process, we here analyze in detail the initial instability phase. On the one hand, 2D relativistic PIC simulations are performed where two unmagnetized, symmetric, and initially cold pair plasmas collide. On the other hand, the instabilities at work are analyzed, as well as the field at saturation and the seed field which gets amplified. For mildly relativistic motions and onward, Weibel modes with ω=0+iδ govern the linear phase. We derive an expression for the duration of the linear phase in reasonable agreement with the simulations.
Another look at divine hiddenness
Authors: CUNEO TERENCE
Published: April 2013

In his fine book The Wisdom to Doubt, J. L. Schellenberg builds a case for religious scepticism by advancing a version of the Hiddenness Argument. This argument rests on the claim that God could not love, in an admirable way, those who seek God while also remaining hidden from them. In this article, I distinguish two arguments for this claim. Neither argument succeeds, I contend, as each rests on an unsatisfactory understanding of the nature of admirable love, whether human or divine.
Limited evidence for allelopathic effects of giant hogweed on germination of native herbs
Authors: Wille Wibke , Thiele Jan , Walker Emer A. , Kollmann Johannes
Published: April 2013

Invasive alien plants often occur in monospecific stands with high density in the invaded range. Production of bioactive secondary metabolites in such stands could have allelopathic effects on germination of native species. We tested this component of the novel weapon hypothesis for Heracleum mantegazzianum, a prominent invader in Europe, using seeds of 11 native herbs exposed to soil or soil extracts from invaded stands, moist seeds or seed extracts of H. mantegazzianum. There was no effect of the various treatments on germination of most species, while germination was reduced in Urtica dioica on invaded soil, in Poa trivialis with H. mantegazzianum seed extract, and negative effects of the essential oil bergapten were found in three species. In P. trivialis the results of the seed extract were not supported by the experiment with added seeds of the invasive plant. Thus, there is limited evidence for allelopathic effects of the invasive H. mantegazzianum on germination of co-occurring native herbs.
An L-band noise radar demonstrator for ground-based measurements of ground surface backscattering
Authors: Maslikowski Lukasz , Kulpa Krzysztof , Krysik Piotr , Dabrowska-Zielinska Katarzyna , Bartold Maciej
Published: April 2013

The paper describes a radar demonstrator that was used to collect L-band range profiles of illuminated ground surface. The measurement results are to be used by the Institute of Geodesy and Cartography as the reference data for satellite image interpretation. The demonstrator is a software-defined noise radar composed of commercial-off-the-shelf elements. The paper conveys the theory of scattering coefficient measurement, system setup, and signal processing as well as the preliminary results of the field measurement campaigns.
IUPAC-NIST Solubility Data Series. 98. Solubility of Polycyclic Aromatic Hydrocarbons in Pure and Organic Solvent Mixtures: Revised and Updated. Part 1. Binary Solvent Mixtures
Authors: Acree William E.
Published: March 2013

This work updates Vols. 54, 58, and 59 in the IUPAC Solubility Data Series and presents solubility data for polycyclic aromatic hydrocarbon solutes dissolved in binary organic solvent mixtures. Published solubility data for anthracene, naphthalene, phenanthrene, phenothiazine, and pyrene that appeared in the primary literature between 1995 to the end of 2011 are compiled and critically evaluated. Experimental solubility data for 360 different solute-binary solvent systems are included in the volume. Solubility data published prior to 1995 were contained in three earlier volumes (Vols. 54, 58, and 59) and are not repeated in this volume.
The molecular frame electric dipole moment and hyperfine interactions in hafnium fluoride, HfF
Authors: Le Anh , Steimle Timothy C. , Skripnikov Leonid , Titov Anatoly V.
Published: March 2013

The (1,0) [17.9]2.5−X2Δ3/2 band of hafnium monofluoride (HfF) has been recorded using high-resolution laser-induced fluorescence spectroscopy both field-free and in the presence of a static electric field. The field-free spectra of 177HfF, 179HfF, and 180HfF were modeled to generate a set of fine and hyperfine parameter for the X2Δ3/2(v = 0) and [17.9]2.5 (v = 1) states. The observed optical Stark shifts for the 180HfF isotopologue were analyzed to produce the molecular frame electric dipole moments of 1.66(1) D and 0.419(7) D for the X2Δ3/2 and [17.9]2.5 state, respectively. Both the generalized effective core potential and all-electron four component approaches were used in ab initio calculations to predict the properties of ground state HfF including equilibrium distance, dipole moments, quadrupole coupling, and magnetic hyperfine constants.
1H relaxation dispersion in solutions of nitroxide radicals: Influence of electron spin relaxation
Authors: Kruk D. , Korpała A. , Kubica A. , Kowalewski J. , Rössler E. A. , Moscicki J.
Published: March 2013

The work presents a theory of nuclear (1H) spin-lattice relaxation dispersion for solutions of 15N and 14N radicals, including electron spin relaxation effects. The theory is a generalization of the approach presented by Kruk et al. [J. Chem. Phys. 137, 044512 (2012)]10.1063/1.4736854. The electron spin relaxation is attributed to the anisotropic part of the electron spin–nitrogen spin hyperfine interaction modulated by rotational dynamics of the paramagnetic molecule, and described by means of Redfield relaxation theory. The 1H relaxation is caused by electron spin–proton spin dipole-dipole interactions which are modulated by relative translational motion of the solvent and solute molecules. The spectral density characterizing the translational dynamics is described by the force-free-hard-sphere model. The electronic relaxation influences the 1H relaxation by contributing to the fluctuations of the inter-molecular dipolar interactions. The developed theory is tested against 1H spin-lattice relaxation dispersion data for glycerol solutions of 4-oxo-TEMPO-d16-15N and 4-oxo-TEMPO-d16-14N covering the frequency range of 10 kHz–20 MHz. The studies are carried out as a function of temperature starting at 328 K and going down to 290 K. The theory gives a consistent overall interpretation of the experimental data for both 14N and 15N systems and explains the features of 1H relaxation dispersion resulting from the electron spin relaxation.
Interaction of magnetic transition metal dimers with spin-polarized hydrogenated graphene
Authors: Ong S. W. , Wu J. , Thong A. Z. H. , Tok E. S. , Kang H. C.
Published: March 2013

The coadsorption of hydrogen and transition metal dimers Fe2, Co2, Ni2, and FeCo on graphene is investigated using density functional theory calculations. Our work is motivated by observations that the magnetic moments of these transition metal dimers are large and that hydrogen adsorption partitions the graphene lattice into magnetic subdomains. Thus, we expect the magnetic dimers to interact strongly with the lattice. Our results show that the majority-spin direction of the lattice electronic states depends upon the dimer identity, the lattice spin polarization being in the same direction as the dimer spin polarization for Fe2 and FeCo, but opposite for Co2 and Ni2. We can understand this by examining the electronic density of states of the dimer and the lattice. We also show that coadsorption significantly increases the adsorption energies of both dimer and hydrogen leading to a more strongly-adsorbed dimer, while the bond length and magnetic moment of the upper dimer atom, the latter important for potential magnetic storage applications, are negligibly changed. Our work shows that the coadsorbed hydrogen and metal dimer interact over a long-range, this interaction being mediated by the hydrogen-induced spin-polarization of the graphene lattice. We obtain general insight into how the elemental identity of these magnetic dimers determines the spin-polarized states on the hydrogenated graphene lattice. These results could be important for potential applications of magnetic properties of decorated graphene lattices.
Coherent spin dynamics in semiconductor quantum dots
Authors: Glazov M. M.
Published: March 2013

We briefly review recent achievements in experimental and theoretical studies of the spin dynamics of electrons and trions under optical pulse-train excitation. The microscopic origin of spin coherence generation, control and detection by means of light is uncovered. The specific features of spin-Faraday, Kerr, and ellipticity signals are analyzed. We show that these effects provide complementary information about spin dynamics. The equilibrium spin dynamics probed by the spin noise spectroscopy is also discussed.
Terahertz single-photon detectors based on quantum wells
Authors: Kajihara Yusuke , Nakajima Takashi , Wang Zhihai , Komiyama Susumu
Published: March 2013

Semiconductor charge-sensitive infrared phototransistors (CSIPs) based on quantum wells are described. They are the only detectors that are able to count single photons in the terahertz region at present. In terms of the noise equivalent power (NEP), the detectors show experimental values of 7 × 10−20 W/Hz1/2, while theoretically expected values are even much lower. These NEP values are by several orders of magnitude lower than any other state-of-the-art highly sensitive detectors. In addition to the outstanding sensitivity, the detectors are featured by strong advantage of huge current responsivity (>1 × 105 A/W) and low output impedance (<10 kΩ). This excellent performance in the above has been obtained for λ = 12–28 μm. By introducing a modified scheme of detection (called “lateral-escape”) along with an improved coupler structure (bowtie antenna), we have achieved similar excellent performance for 45 μm. The CSIP provides extremely promising detectors for a variety of applications covering a wide spectral range of 12–100 μm.
Electron spin dynamics and optical orientation of Mn2+ ions in GaAs
Authors: Akimov I. A. , Dzhioev R. I. , Korenev V. L. , Kusrayev Yu. G. , Sapega V. F. , Yakovlev D. R. , Bayer M.
Published: March 2013

We present an overview of spin-related phenomena in GaAs doped with low concentration of Mn-acceptors (below 1018 cm−3). We use the combination of different experimental techniques such as spin-flip Raman scattering and time-resolved photoluminescence. This allows to evaluate the time evolution of both electron and Mn spins. We show that optical orientation of Mn ions is possible under application of weak magnetic field, which is required to suppress the manganese spin relaxation. The optically oriented Mn2+ ions maintain the spin and return part of the polarization back to the electron spin system providing a long-lived electron spin memory. This leads to a bunch of spectacular effects such as non-exponential electron spin decay and spin precession in the effective exchange fields.
Bridging semiconductor and magnetism
Authors: Ohno H.
Published: March 2013

Carrier-induced ferromagnetism and its manipulation in Mn-doped III-V semiconductors, such as (In,Mn)As and (Ga,Mn)As, offer a wide variety of phenomena that originate from the interplay between magnetism and semiconducting properties, forming a bridge between semiconductor and magnetism. A review is given on the electrical manipulation of magnetism, its understanding, and potential applications both from the physics point of view and from the technological point of view. The electric-field study on magnetism is now being extended to magnetic metals, leading to an energy efficient way of magnetization reversal important for future semiconductor integrated circuit technology, yet another route to bridge semiconductor and magnetism in a fruitful way.
Nexus between directionality of terahertz waves and structural parameters in groove patterned InAs
Authors: Yim Jong-Hyuk , Min Kyunggu , Jeong Hoonil , Lee Eun-Hye , Song Jin-Dong , Jho Young-Dahl
Published: March 2013

We performed terahertz (THz) time-domain spectroscopy in various geometries, for characterizing the directivity of THz waves emitted from groove patterned InAs structures. We first identified two transient transport processes as underlying THz emission mechanisms in InAs epilayers with different thicknesses. Carrier drift around the surface depletion region was predominant for the THz wave generation in the thin sample group (10–70 nm), whereas electronic diffusion overrode the drift currents in the thick sample group (370–900 nm) as revealed by the amplitude change and phase reversal. Through a combination of electron-beam lithography and inductively coupled plasma etching in 1 μm-thick InAs epilayers, we could further periodically fabricate either asymmetric V-groove patterns or symmetric parabolic apertures. The THz amplitude was enhanced, particularly along the line-of-sight transmissive direction when the periodic groove patterns act as microscale reflective mirrors separated by a scale of the diffusion length.