bluuebunny/crossref_metadata_2025 huggingface dataset:
Where have all the houses (among other things) gone? Some critical reflections on urban agriculture
Authors: DeLind Laura B.
Published: January 2014

Urbandale Farm (Lansing, MI) has much in common with other urban agricultural projects throughout the US and especially those in the rust-belt cities of the Midwest. It raises food for an economically challenged neighborhood. It offers opportunities for local participation, education and job creation, and it is supported by diverse public and private institutions. By all official accounts, Urbandale Farm is good at what it does. Its acreage, production, income and entrepreneurial activities are all increasing, and it has become a poster child for urban agriculture throughout the city. However, despite its good work (or possibly because of it), Urbandale Farm, and urban agriculture more generally, may unwittingly be helping to rationalize the displacement and continued social and political inequity of urban neighbors rather than reinforcing greater place-making, neighborhood empowerment and sustainability. Using Urbandale Farm as a case in point, this paper critically explores how urban agriculture is being used by some scholars, activists, governmental offices and agencies to transform fragile neighborhoods. It questions some of the movement's underlying assumptions as well as some of its actual benefits and beneficiaries. The paper also offers suggestions—for the purpose of initiating a more nuanced conversation—on how urban agriculture can be reconfigured philosophically and practically to shed its neoliberal tendencies and contribute to a more structurally based social and political transformation.
The impact of additional initial face-to-face sessions on engagement within an Improving Access to Psychological Therapies service
Authors: Mander Helen
Published: January 2014

Despite substantial investment, Improving Access to Psychological Therapies (IAPT) services in some areas continue to find that demand exceeds provision, leading to waiting lists for therapy. Routine engagement in services is low, with almost half of clients disengaging with the service before or after the initial contact. An audit was carried out to evaluate the impact of introducing a face-to-face initial session within the high-intensity step of an IAPT service. The service structure and pathway of one regional IAPT service is described. A longitudinal observational design was used. All clients discharged from the service within two calendar months – before and after the introduction of an initial face-to-face session were identified. Electronic records were reviewed for each client. Introduction of an initial face-to-face session was associated with an increase in clients attending at least one therapy session and clients completing a course of therapy. Inclusion of an initial face-to-face engagement session may take up additional time, but is likely to be worthwhile in regards to associated benefits in terms of client engagement.
Power controlled FM-UWB system with a wideband RF carrier for body area network applications
Authors: Lee Heejong , Lee Seok-Jae , Yoon Won-Sang , Han Sang-Min
Published: January 2014

An FM-ultra-wideband (UWB) system with a wideband RF carrier (WRC) is proposed for wireless body area network applications. The proposed system can control the channel power by means of an adjustable carrier bandwidth (BW), while the conventional one with a CW carrier (CWC) makes use of peak power control. The implemented WRC system performances have been evaluated for the WRC generation and digital data transmission. In addition, transmission performances have been compared with that of a conventional CWC system by bit-error-rate (BER) tests. For random data of a 29−1 pattern at a data-rate of 64 kbps, in spite of the flexible carrier BW, the WRC system has presented excellent transmission capability compared with that of the CWC system.
A way forward in protecting health services in conflict: moving beyond the humanitarian paradigm
Authors: Rubenstein Leonard S.
Published: January 2014

Attacks on health workers, clinics, hospitals, ambulances and patients during periods of armed conflict or civil disturbance pose enormous challenges to humanitarian response and constitute affronts to the imperatives of human rights and civilian protection. Violence inflicted on humanitarian aid workers is gaining the global attention it warrants. While the number of attacks on aid workers has decreased in recent years, in a handful of places, notably Sudan, Afghanistan, and Somalia, they have become more spectacular and frightening, with aid agencies targeted for kidnapping and subjected to use of explosives because of their perceived affiliation with Western governments. The assaults have galvanised the humanitarian aid community to track attacks and to engage in intensive and sophisticated discussion of means to increase operational security. After worldwide consultation, in 2011 the United Nations (UN) Office for the Coordination of Humanitarian Affairs (OCHA) issued a report that summarised the fruits of experience and stimulated consideration of security strategies for aid providers. By contrast, however, until very recently the far larger number of incidents of violence inflicted on and interference with indigenous health services and on international and local development agencies by state and armed groups has received comparatively little attention.
Influence of Affective Changes on Behavioral and Cognitive Performances After Acute Bout of Exhaustive Exercise
Authors: Jain Preeti , Aprajita  , Jain Peeyush , Kumar Jain Ajay , Babbar Rashmi
Published: January 2014

The present study was conducted to evaluate the influence of acute, exhaustive, exercise on affective responses (affective valence and activation) and behavioral and cognitive performances in medical students using circumplex model, reaction time (RT), and P300, respectively. Twelve healthy, untrained, male medical students participated in self-controlled, counterbalanced trial conducted over two sessions: baseline and exercise. In the baseline session, recordings of auditory reaction time (ART), visual RT (VRT), and P300 latency and amplitude (using acoustic “oddball” paradigm) were taken at the end of 15 min seated rest. Exercise session comprised of continuous maximal graded incremental exercise until volitional exhaustion, on a computer-based motorized treadmill and recordings done after heart rate returned to within +10% of pre-exercise values. Perceived exertion, affective valence, and activation were assessed pre-exercise, during (30 s before the end of each stage), and post-exercise (immediately, 5 and 10 min after) by Borg’s scale, feeling scale (FS), and felt-arousal scale (FAS), respectively. There was marked variability in individual affective responses to a single bout of exhaustive exercise with few subjects showing activated pleasure (Energetic Arousal) and others showing activated displeasure (Tense arousal). The results further indicated an overall improvement in behavioral (as evidenced by the decrease in ART and VRT) and cognitive performances (as evidenced by increase in the P300 amplitude and decrease in the P300 latency) in medical students in the exercise session relative to the baseline session despite bidirectional shifts in valence suggesting that interdependent neural systems might mediate these effects.
Brief Report: Some Remarks About the Response Relatedness of the Error Negativity
Authors: Hoffmann Sven
Published: January 2014

The error negativity (Ne) is a prominent response-related potential reflecting error processing or response monitoring processes. Despite the huge amount of literature dealing with the Ne, only few studies investigated how close the Ne is related to the kind of response collected by the experimental setup. The present study investigated whether the Ne differs between force locked and force level related (aka button press) data. Indeed, the Ne was more pronounced for force onset compared to level trigger and appeared to be related to the steepness of the raise of force. These results implicate that the parameterization of the Ne has to be treated with caution under certain circumstances and it appears to be advisable to use force onset or the electromyogram to detect response onset if timing or latency is relevant.
Attentional Modulation of the Emotional Expression Processing Studied with ERPs and sLORETA
Authors: Wronka Eligiusz , Walentowska Wioleta
Published: January 2014

Recent ERP studies demonstrate that the processing of facial emotional expression can be modulated by attention. The aim of the present study was to investigate the neural correlates of attentional influence on the emotional expression processing at early stages. We recorded ERP responses to facial stimuli containing neutral versus emotional expression in two different conditions. The first task was to discriminate facial expressions, while the second task was to categorize face gender. Enhanced positivity at occipital and occipito-temporal locations between 110 and 170 ms poststimulus was elicited by facial stimuli presented in the expression task when compared to the gender task. This effect temporally overlapped with the P1 and N170 components, which reflect the early stages of face processing. To localize the sources of the brain activity underlying observed attentional modulation, we used Standardized Low Resolution Electromagnetic Tomography. Enhanced activity within the extrastriate cortex for the expression task was obtained as the reflection of early ERP effect. Additionally, we found stronger activation within the superior temporal and the fusiform gyrus of the right hemisphere in the expression task when compared to the gender task. Our findings undoubtedly confirm that early stages of the emotional expression processing can be modified by top-down attention.
Nuisance or Remedy? The Utility of Stylistic Responding as an Indicator of Data Fabrication in Surveys
Authors: Kemper Christoph J. , Menold Natalja
Published: January 2014

Stylistic responding is usually seen as a nuisance by researchers working with questionnaire data due to its contaminating effects on the measurement of substantiative constructs. We demonstrate that stylistic responding may be useful to improve the data quality in surveys by allowing for an identification of deviant interviewer behavior – data fabrication – in survey fieldwork. Stylistic responding in N = 710 genuine and corresponding falsified interviews was compared. Genuine survey data was collected in paper-assisted personal interviews. Corresponding falsified data were obtained by instructing falsifiers to fabricate data based on person descriptions of genuine survey respondents. Acquiescent and midpoint responding, response range, and self-enhancement emerged as useful predictors of falsification. These indicators might now be used to develop and refine multivariate statistical methods for the ex-post identification of cheating interviewers in survey fieldwork.
Validity Concerns With Multiplying Ordinal Items Defined by Binned Counts
Authors: McGinley James S. , Curran Patrick J.
Published: January 2014

Social and behavioral scientists often measure constructs that are truly discrete counts by collapsing (or binning) the counts into a smaller number of ordinal responses. While prior quantitative research has identified a series of concerns with similar binning procedures, there has been a lack of study on the consequences of multiplying these ordinal items to create a desired index. This measurement strategy is incorporated in many research applications, but it is particularly salient in the study of substance use where the product of ordinal quantity (number of drinks) and frequency (number of days) items is used to create an index of total consumption. In the current study, we demonstrate both analytically and empirically that this multiplicative procedure can introduce serious threats to construct validity. These threats, in turn, directly impact the ability to accurately measure alcohol consumption.
Specifying Measurement Error Correlations in Latent Growth Curve Models With Multiple Indicators
Authors: Grilli Leonardo , Varriale Roberta
Published: January 2014

In this tutorial paper we focus on a multi-item Latent Growth Curve model for modeling change across time of a latent variable measured by multiple items at different occasions: in the structural part the latent variable grows according to a random slope linear model, whereas in the measurement part the latent variable is measured at each occasion by a conventional factor model with time-invariant loadings. The specification of a multi-item Latent Growth Curve model involves several interrelated choices: indeed, the features of the structural part, such as the functional form of the growth, are linked to the features of the measurement part, such as the correlation structure across time of measurement errors. In the paper, we give guidelines on the specification of the variance-covariance structure of measurement errors. In particular, we investigate the empirical implications of different specification strategies through an analysis of student ratings collected in four academic years about courses of the University of Florence. In the application we compare three correlation structures (independence, lag-1, and compound symmetry), illustrating the differences in terms of substantive assumptions, model fit, and interpretability of the results.
Can the “Musical Stroop” Task Replace the Classical Stroop Task?
Authors: Zakay Dan
Published: January 2014

The musical Stroop task is analyzed and compared to the classical Stroop task. The analysis indicates that the two tasks differ in the following significant characteristics: ecological validity, the interrelations between the two perceptual dimensions involved, the nature of the automatic process and the existence of a potential Garner interference. It is concluded that the musical task has no advantage over the classical task.
Gender and Ethnic Composition of Assessment Centers and Its Relationship to Participants’ Success
Authors: Falk Amir , Fox Shaul
Published: January 2014

Although assessment centers (ACs) are recognized for their high validity, the lack of standardization associated with some aspects of ACs may limit their strength. One source for lack of standardization is the demographic composition within the AC, which may affect members’ actual or perceived performance. We investigate the influences of gender and ethnicity (Jewish vs. Arab) compositions of participants and assessors on participants’ success in ACs for educational managerial positions in Israel. Participants were 384 candidates from 44 ACs. The participants’ success was determined by the assessors’ subjective impressions. A higher proportion of female participants was associated with higher scores for males, especially when the proportion of female assessors was high. A higher proportion of Arab participants was associated with higher scores for Jews. These findings demonstrate the problems associated with the lack of AC standardization.
Trajectories of Perceived Employability and Their Associations With Well-Being at Work
Authors: Kirves Kaisa , Kinnunen Ulla , De Cuyper Nele , Mäkikangas Anne
Published: January 2014

The first aim of this study was to identify trajectories of perceived employability (PE) with a longitudinal person-centered approach, accounting for both the level of PE and changes in PE. The second aim was to examine how the trajectories were related to well-being at work (i.e., vigor at work, job satisfaction, and job exhaustion) with a variable-centered approach. The data were collected in two Finnish universities (N = 926) during 2008–2010 with three measurement points. Growth Mixture Modeling identified four trajectories, which differed in level, stability, and change in PE across time: we established two trajectories with stable PE (88% of the participants), and two trajectories with a nonlinear change pattern in PE (12%). Furthermore, variable-centered analyses showed that the level of PE was positively associated with well-being at work. Moreover, in one change trajectory, the increase in PE was associated with an increase in vigor at work. Overall, these results indicate that PE can be seen as a personal resource. However, the effect of PE is minor in terms of change in employee well-being among highly educated employees.
Simultaneous determination of peracetic acid and acetic acid by titration with NaOH
Authors: Sode Frank
Published: January 2014

This paper describes a fast and easy method to analyze peracetic acid in mixtures with both acetic acid and hydrogen peroxide.
Crystallographic determination of solid-state structural transformations in a dynamic metal–organic framework
Authors: Li Gui-Lian , Liu Guang-Zhen , Ma Lu-Fang , Xin Ling-Yun , Li Xiao-Ling , Wang Li-Ya
Published: January 2014

A dynamic MOF with hierarchical pores displays various SC–SC structural transformations including reversible desolvation–resolvation, I2 uptake–release, and photochemical [2+2] cycloaddition.
Delayed electron–hole pair recombination in iron(iii)-oxo metal–organic frameworks
Authors: Laurier Katrien G. M. , Fron Eduard , Atienzar Pedro , Kennes Koen , Garcia Hermenegildo , Van der Auweraer Mark , De Vos Dirk E. , Hofkens Johan , Roeffaers Maarten B. J.
Published: January 2014

The photodynamic properties of a series of Fe(iii)-MOFs have been examined via redox reactions with N,N,N′,N′-tetramethyl-p-phenylenediamine as an electron donor and methyl viologen as an electron acceptor. Furthermore, photogeneration of long-lived species in MIL-88B(Fe) has been proven via transient absorption spectroscopy.
Halogen-bond and hydrogen-bond interactions between three benzene derivatives and dimethyl sulphoxide
Authors: Zheng Yan-Zhen , Wang Nan-Nan , Zhou Yu , Yu Zhi-Wu
Published: January 2014

We examine and compare the halogen- and hydrogen-bonding interactions between benzene derivatives and DMSO by experimental and computational methods.
Stable selones in glutathione-peroxidase-like catalytic cycle of selenonicotinamide derivative
Authors: Prabhu Parashiva , Singh Beena G. , Noguchi Masato , Phadnis Prasad P. , Jain Vimal K. , Iwaoka Michio , Priyadarsini K. Indira
Published: January 2014

Stable selone formation in 2,2′-diselenobis[3-amidopyridine], reduces unwanted sulfur exchange reaction in glutathione peroxidase like catalytic cycle and enhances its enzyme activity.
Syntheses and biological evaluation of 2-amino-3-acyl-tetrahydrobenzothiophene derivatives; antibacterial agents with antivirulence activity
Authors: The Dang Hung , Chorell Erik , Uvell Hanna , Pinkner Jerome S. , Hultgren Scott J. , Almqvist Fredrik
Published: January 2014

The synthesis, SAR and effects of 2-amino-3-acyl-tetrahydrobenzothiophene derivatives on pilus assembly inE. colihave been described.
Generalized green synthesis of diverse LnF3–Ag hybrid architectures and their shape-dependent SERS performances
Authors: Zhang Maofeng , Zhao Aiwu , Li Da , Sun Henghui , Wang Dapeng , Guo Hongyan , Gao Qian , Gan Zibao , Tao Wenyu
Published: January 2014

Diverse LnF3–Ag hybrid architectures as substrates exhibit superior SERS performance and excellent detection sensibility for analytes.
Effect of depositing silver nanoparticles on BiVO4in enhancing visible light photocatalytic inactivation of bacteria in water
Authors: Booshehri Amin Yoosefi , Chun-Kiat Goh Simon , Hong Jindui , Jiang Rongrong , Xu Rong
Published: January 2014

Metallic Ag nanoparticles deposited on BiVO4promote the separation of photo-induced electron/hole pairs for the generation of reactive oxygen species, leading to excellent photocatalytic disinfection activity under both visible light and natural sunlight.
Amplified inhibition of the electrochemical signal of graphene–thionine nanocomposites using silica nanoprobes for ultrasensitive electrochemical immunoassays
Authors: Lai Guosong , Yin Cuiying , Tan Xiangen , Zhang Haili , Yu Aimin
Published: January 2014

The amplified inhibition of the electrochemical signal of graphene–thionine nanocomposites using silica nanoprobes enabled a novel ultrasensitive immunoassay method.
Efficient diffusive mechanisms of O atoms at very low temperatures on surfaces of astrophysical interest
Authors: Congiu Emanuele , Minissale Marco , Baouche Saoud , Chaabouni Henda , Moudens Audrey , Cazaux Stephanie , Manicò Giulio , Pirronello Valerio , Dulieu François
Published: January 2014

At the low temperatures of interstellar dust grains, it is well established that surface chemistry proceeds via diffusive mechanisms of H atoms weakly bound (physisorbed) to the surface. Until recently, however, it was unknown whether atoms heavier than hydrogen could diffuse rapidly enough on interstellar grains to react with other accreted species. In addition, models still require simple reduction as well as oxidation reactions to occur on grains to explain the abundances of various molecules. In this paper we investigate O-atom diffusion and reactivity on a variety of astrophysically relevant surfaces (water ice of three different morphologies, silicate, and graphite) in the 6.5–25 K temperature range. Experimental values were used to derive a diffusion law that emphasizes that O atoms diffuse by quantum mechanical tunnelling at temperatures as low as 6.5 K. The rates of diffusion on each surface, based on modelling results, were calculated and an empirical law is given as a function of the surface temperature. The relative diffusion rates are kH2Oice > ksil > kgraph ≫ kexpected. The implications of efficient O-atom diffusion over astrophysically relevant time-scales are discussed. Our findings show that O atoms can scan any available reaction partners (e.g., either another H atom, if available, or a surface radical like O or OH) at a faster rate than that of accretion. Also, as dense clouds mature, H2 becomes far more abundant than H and the O : H ratio grows, and the reactivity of O atoms on grains is such that O becomes one of the dominant reactive partners together with H.
Quasi-classical Trajectory Study of F+H2O→HF+OH Reaction: Influence of Barrier Height, Reactant Rotational Excitation, and Isotopic Substitution
Authors: Li Jun , Guo Hua
Published: January 2014

The reaction dynamics of the F+H2O/D2O→HF/DF+OH/OD are investigated on an accurate potential energy surface (PES) using a quasi-classical trajectory method. For both isotopomers, the hydrogen/deuterium abstraction reaction is dominated by a direct rebound mechanism over a very low “reactant-like” barrier, which leads to a vibrationally hot HF/DF product with an internally cold OH/OD companion. It is shown that the lowered reaction barrier on this PES, as suggested by high-level ab initio calculations, leads to a much better agreement with the experimental reaction cross section, but has little impact on the product state distributions and mode selectivity. Our results further indicate that rotational excitation of the H2O reactant leads to significant enhancement of the reactivity, suggesting a strong coupling with the reaction coordinate.
Ultrafast Excited State Dynamics of trans-4-Aminoazobenzene Studied by Femtosecond Transient Absorption Spectroscopy
Authors: Wang Ya-ping , Zhang Song , Sun Si-mei , Liu Kai , Zhang Bing
Published: January 2014

The ultrafast excited state dynamics of trans-4-aminoazobenzene (trans-4-AAB) in ethanol was investigated by femtosecond transient absorption spectroscopy. After being excited to the S2 state by 400 nm, trans-4-AAB decays from the S2 state to the hot S1 state by internal conversion with time constant of ∼70 fs. The photoisomerization through inversion mechanism on the S1potential energy surface and the internal conversion from the S1 state to the hot S0 state are observed, respectively. The average timescale of these two decay pathways is ∼0.7 ps. And the vibrational cooling of the hot S0 state of cis- and trans-4-AAB occur with time constants of ∼4 and ∼13 ps, respectively. Furthermore, the ultrafast intersystem crossing process are also observed. The timescale of intersystem crossing from the S2 state to the T4 state is about 480 ps while from the S1 state to the T2 state is ∼180 ps.
Theoretical Investigation on the Absence of Spore Photoproduct Analogue at Cytosine-Thymine Site
Authors: Du Qian , Zhao Hong-mei , Su Hong-mei
Published: January 2014

As a well known DNA photolesion product, the special UV induced pyrimidine dimmer called spore photoproduct (SP), has aroused strong research interests. The SP formation was reported solely between two adjacent thymidine residues. It remains unclear in pervious experimental observations why there is an absence of the cytosine-derived SP-like photoproduct formation at the cytosine containing DNA strand, although the cytosine residue holds great similarity to thymine in terms of molecular structure. From a theoretical perspective, we have explored this issue in this work by means of density functional theory at the B3LYP/6-311++G(d,p)//B3LYP/6-31G(d,p) level for the DNA dinucleotide fragment, cytosine phosphate thymine (CpT). Key factors blocking the formation of the SP-like product between two adjacent cytosine and thymidine residues are revealed. Instead of undergoing photochemical SP reaction, a photophysical deactivation pathway back to the ground state turns out to be favorable for the CpT dinucleotide fragment.
Ion Pairing Kinetics Does not Necessarily Follow the Eigen-Tamm Mechanism
Authors: Zhang Qiang , Zhang Bing-bing , Jiang Ling , Zhuang Wei
Published: January 2014

The most recognized and employed model of the solvation equilibration in the ionic solutions was proposed by Eigen and Tamm, in which there are four major states for an ion pair in the solution: the completely solvated state, 2SIP (double solvent separate ion pair), SIP (single solvent separate ion pair), and CIP (contact ion pair). Eigen and Tamm suggested that the transition from SIP to CIP is always the slowest step during the whole pairing process, due to a high free energy barrier between these two states. We carried out a series of potential of mean force calculations to study the pairing free energy profiles of two sets of model monoatomic 1:1 ion pairs 2.0:x and xx:2.0. For 2.0:x pairs the free energy barrier between the SIP and CIP states is largely reduced due to the salvation shell water structure. For these pairs the SIP to CIP transition is thus not the slowest step in the ion pair formation course. This is a deviation from the Eigen-Tamm model.
Cyclic M(SO2) (M=Zn, Cd) and its Anions: Matrix Infrared Spectra and DFT Calculations
Authors: Li Guang-jun , Liu Xing , Zhao Jie , Xu Bing , Wang Xue-feng
Published: January 2014

Reaction of laser ablated zinc and cadmium atoms with SO2 molecules was studied by low temperature matrix isolation infrared spectroscopy. Cyclic M(SO2) and anion M(SO2)− (M=Zn, Cd) were produced in excess argon and neon, which were identified by 34SO2 and S18O2 isotopic substitutions. The observed infrared spectra and molecular structures were confirmed by density functional theoretical calculations. Natural charge distributions indicated significant electron transfer from s orbitals of zinc or cadmium metal atom to SO2 ligand and cyclic M(SO2) complexes favored “ion pair” M+(SO2)− formation, which were trapped in low temperature matrices. In addition Zn-O or Cd-O bond in M(SO2) exhibited strong polarized covalent character. Reaction of Hg atom with SO2 was also investigated, but no reaction product was observed, due to the relativistic effect that resulted in the contraction of 6s valence shell and high ionization potential of Hg atom.
Theoretical Characterization of Chiral Carbon Nanotube Encapsulating Ellipsoidal C70
Authors: Kan Er-jun , Yao Qiu-shi
Published: January 2014

The molecular orientation of ellipsoidal C70 in carbon nanotubes is carefully studied by first principles calculations. Using (14, 7) single-wall carbon nanotube (SWCNT) as a prototype material, we explored that the weak chemical interaction between SWCNT and C70 was the crucial factor to determine the molecular orientation. However, the small energy difference makes the distinguishment of two possible molecular orientations difficult. By simulating scanning tunneling microscope images and optical properties, we found that local electronic states sensitively depended on the molecular orientation of ellipsoidal C70, which provided a practical way of using scanning tunneling microscope to recognize the molecular orientation of ellipsoidal C70.
Simple Synthesis of New Mixed Isocyanide-NHC-Platinum(II) Complexes and Their Catalytic Activity
Authors: Hubbert Christoph , Breunig Marcus , Carroll Kristen J. , Rominger Frank , Hashmi A. Stephen K.
Published: January 2014

Using the new modular and convergent approach to isocyanide-N-hetrocyclic carbene-platinum(ii) complexes, eight new compounds have been synthesised. For three of these, detailed structural data could be obtained by X-ray crystal structure analyses. This new family of organoplatinum complexes is catalytically active for hydrosilylation reactions; styrene and phenylacetylene could be used as substrates; triethylsilane and 1,1,1,3,5,5,5-heptamethyltrisiloxane could be used as reagents. With some of the new platinum pre-catalysts, excellent regioselectivities of up to 98 : 2 could be obtained, and turnover numbers up to 840 were achieved.
Quantifying the distribution of nanodiamonds in pre-Younger Dryas to recent age deposits along Bull Creek, Oklahoma Panhandle, USA
Authors: Bement Leland C. , Madden Andrew S. , Carter Brian J. , Simms Alexander R. , Swindle Andrew L. , Alexander Hanna M. , Fine Scott , Benamara Mourad
Published: January 2014

Significance

In 2007, scientists proposed that the start of the Younger Dryas (YD) chronozone (10,900 radiocarbon years ago) and late Pleistocene extinctions resulted from the explosion of a comet in the earth’s atmosphere. The ET event, as it is known, is purportedly marked by high levels of various materials, including nanodiamonds. Nanodiamonds had previously been reported from the Bull Creek, Oklahoma, area. We investigate this claim here by quantifying the distribution of nanodiamonds in sediments of different periods within the Bull Creek valley. We found high levels of nanodiamonds in YD boundary deposits, supporting the previous claim. A second spike in nanodiamonds during the late Holocene suggests that the distribution of nanodiamonds is not unique to the YD.
Development of pattern vision following early and extended blindness
Authors: Kalia Amy , Lesmes Luis Andres , Dorr Michael , Gandhi Tapan , Chatterjee Garga , Ganesh Suma , Bex Peter J. , Sinha Pawan
Published: January 2014

Significance

Deprivation of vision during typical age-defined critical periods results in seemingly irreversible changes in neural organization and behavior in animals and humans. We describe visual development in a unique population of patients who were blind during typical critical periods before removal of bilateral cataracts. The rarity of such cases has previously limited empirical investigations of this issue. Surprisingly, we find substantial improvement after sight onset in contrast sensitivity, a basic visual function that has well-understood neural underpinnings. Our results show that the human visual system can retain plasticity beyond critical periods, even after early and extended blindness.
Mutational landscape of yeast mutator strains
Authors: Serero Alexandre , Jubin Claire , Loeillet Sophie , Legoix-Né Patricia , Nicolas Alain G.
Published: January 2014

Significance

Deficiencies in genome maintenance genes (so-called mutator genes) result in increased mutagenesis that impacts cell evolvability. How the mutational processes drive the evolution of genome structure is not well understood. Here, we used high-throughput sequencing to characterize the mutation events (from punctual mutations to large chromosomal rearrangements) that occurred in mutation accumulation lines derived from a broad set of yeast mutator strains. Establishing genome-wide mutation profiles revealed that each mutator exhibits a unique and sometimes complex mutational signature. Our results also show how the dynamics of mutation accumulation can generate different genomes.
Programmed Allee effect in bacteria causes a tradeoff between population spread and survival
Authors: Smith Robert , Tan Cheemeng , Srimani Jaydeep K. , Pai Anand , Riccione Katherine A. , Song Hao , You Lingchong
Published: January 2014

Significance

Understanding how species spread and survive is important in many biological contexts. The ability to disperse has been shown to enhance spread in some species but detract in others. Theoretical studies have predicted that these observations may be due to the Allee effect. To test this theory, we engineeredEscherichia colito have an Allee effect. Using these bacteria, we found that if dispersal is too fast or too slow, a population cannot spread. By manipulating the number of patches, we uncovered tradeoffs that control spread and survival. Finally, we demonstrate that fluctuations in growth may serve to determine if spread occurs. Our results may be useful in controlling invasive species and the spread of infectious diseases.
Functional changes of the reward system underlie blunted response to social gaze in cocaine users
Authors: Preller Katrin H. , Herdener Marcus , Schilbach Leonhard , Stämpfli Philipp , Hulka Lea M. , Vonmoos Matthias , Ingold Nina , Vogeley Kai , Tobler Philippe N. , Seifritz Erich , Quednow Boris B.
Published: January 2014

Significance

Social interaction deficits in drug users likely impede treatment, increase the burden of the affected families, and consequently contribute to the high costs for society associated with addiction. However, the neural origin contributing to altered social interaction in drug users is unknown thus far. The present study illuminates the nature of basic social interaction deficits as exemplified by social gaze behavior in cocaine users by applying behavioral, psychophysiological, and functional brain-imaging methods. The results suggest that basal social interaction impairments probably arise from blunted social reward processing that was again related to impaired real-life social behavior in cocaine users. These results point to the importance of reinstatement of social reward in the treatment of stimulant addiction.
Quorum sensing controls hyphal initiation in
Candida albicans
through Ubr1-mediated protein degradation
Authors: Lu Yang , Su Chang , Unoje Ohimai , Liu Haoping
Published: January 2014

Significance

Quorum sensing is a mechanism for intra- and/or interspecies microbial communication of cell density information. It can regulate group behaviors, like virulence, biofilm formation, and competence.
Candida albicans
is a major opportunistic fungal pathogen of humans that resides in the gastrointestinal tract and mucosal membranes as a commensal microbiota. Its capacity to switch between yeast and hyphal morphologies is a key virulence factor. The morphologic transition is inhibited by the sesquiterpine alcohol farnesol, a quorum-sensing molecule in
C. albicans
. Here, we show that farnesol controls hyphal initiation through the N-end rule pathway-mediated protein degradation. This regulation provides molecular insights into how
C. albicans
cells communicate in the host microbiota to regulate the transition between commensal and pathogenic growth states.
CLE-CLAVATA1 peptide-receptor signaling module regulates the expansion of plant root systems in a nitrogen-dependent manner
Authors: Araya Takao , Miyamoto Mayu , Wibowo Juliarni , Suzuki Akinori , Kojima Soichi , Tsuchiya Yumiko N. , Sawa Shinichiro , Fukuda Hiroo , von Wirén Nicolaus , Takahashi Hideki
Published: January 2014

Significance

Morphological adjustment is an important strategy for survival of living organisms in challenging environments. Plasticity of the root system architecture is critical for nutrient acquisition in plants. Among the essential elements, nitrogen (N) strongly affects root development. This article uncovers a key signaling mechanism regulating the outgrowth of lateral roots and expansion of plant root systems. The mechanism demonstrated in this study suggests an important morphological strategy for plant survival in N-poor environments.
Detection of solar wind-produced water in irradiated rims on silicate minerals
Authors: Bradley John P. , Ishii Hope A. , Gillis-Davis Jeffrey J. , Ciston James , Nielsen Michael H. , Bechtel Hans A. , Martin Michael C.
Published: January 2014

Significance

Whether water is produced by solar wind (SW) radiolysis has been debated for more than four decades. In this paper, we exploit the high spatial resolution of electron microscopy and sensitivity of valence electron energy-loss spectroscopy to detect water (liquid or vapor) in vesicles within (SW-produced) space-weathered rims on interplanetary dust particle (IDP) surfaces. Water in the rims has implications for the origin of water on airless bodies like the Moon and asteroids, the delivery of water to the surfaces of terrestrial planets, and the production of water in other astrophysical environments. In particular, water and organic carbon were likely delivered simultaneously by the high flux of IDPs accreted by the early Earth and other terrestrial planets.
Paternally induced transgenerational inheritance of susceptibility to diabetes in mammals
Authors: Wei Yanchang , Yang Cai-Rong , Wei Yan-Ping , Zhao Zhen-Ao , Hou Yi , Schatten Heide , Sun Qing-Yuan
Published: January 2014

Significance

Increasing evidence suggests that certain acquired traits can be transmitted to the next generation. However, controversy over the inheritance of acquired traits remains, as the exact molecular and mechanistic basis for these observations remains largely unclear. In this study, using a nongenetic prediabetes mouse model, we have shown that environmentally induced epigenetic alterations in sperm can be inherited to the next generation. Paternal prediabetic conditions affect epigenetic marks in offspring and can be inherited for several generations. This finding provides a molecular basis for the inheritance of acquired traits and may have implications in explaining the prevalence of obesity, type 2 diabetes, and other chronic metabolic diseases.
Spatiotemporal separation of PER and CRY posttranslational regulation in the mammalian circadian clock
Authors: St. John Peter C. , Hirota Tsuyoshi , Kay Steve A. , Doyle Francis J.
Published: January 2014

Significance

Maintaining robust circadian rhythms has been linked to longevity and metabolic health. Because these rhythms are disturbed by factors such as jet lag, shift work, and high-fat diets, there is interest in developing pharmacological control strategies to modulate circadian function. The design of therapeutic strategies is currently limited by the lack of a clear mechanistic understanding of interactions between posttranslational regulators, as efficient control of clock behavior will likely require several simultaneous modulations. Here we show fundamentally different clock responses from the manipulation of two clock regulators previously thought to act via similar mechanisms. Using mathematical modeling, we provide a mechanistic interpretation for the relationship between these two regulators, lending insight into circadian regulation and potential pharmacological control.
Structure and mechanism of a eukaryotic transmembrane ascorbate-dependent oxidoreductase
Authors: Lu Peilong , Ma Dan , Yan Chuangye , Gong Xinqi , Du Mingjian , Shi Yigong
Published: January 2014

Significance

Vitamin C (also known as ascorbate), an essential nutrient for humans, plays an important role in protection against oxidative stress. The ascorbate-dependent oxidoreductase cytochrome b
561
(Cyt b
561
) is a family of highly conserved, multipass transmembrane enzymes found only in eukaryotes. Cyt b
561
plays a key role in ascorbate recycling and many other important physiological processes, such as iron absorption. The atomic structure and functional mechanism of Cyt b
561
remain unknown. In this study, we report the high-resolution crystal structures of Cyt b
561
in both ascorbate-free and ascorbate-bound states. Our structural and biochemical analyses identify a general functional mechanism for the Cyt b
561
family.
Variants of mouse DNA polymerase κ reveal a mechanism of efficient and accurate translesion synthesis past a benzo[
a
]pyrene dG adduct
Authors: Liu Yang , Yang Yeran , Tang Tie-Shan , Zhang Hui , Wang Zhifeng , Friedberg Errol , Yang Wei , Guo Caixia
Published: January 2014

Significance

Polycyclic aromatic hydrocarbons (PAHs) constitute a class of well-characterized environmental pollutants. Benzo[
a
]pyrene (BP), a typical and extensively studied PAH, can be metabolically converted to mutagenic reactive intermediates in vivo to form the major 10
S
(+)-
trans
-
anti
-BP diol epoxide (BPDE)-
N
2
-dG (BPDE-dG) lesions and thus impede DNA replication and enhance mutagenesis. DNA polymerase κ (Polκ) is the only known DNA polymerase in mouse or human cells that can bypass the BPDE-dG adduct in an error free manner, thereby reducing mutation risk. Here we show that a structural gap and the N-clasp of Polκ are essential for accurate translesion synthesis of the bulky adduct.
Black Pod Syndrome ofLupinus angustifoliusIs Caused by Late Infection withBean yellow mosaic virus
Authors: Kehoe M. A. , Buirchell B. J. , Coutts B. A. , Jones R. A. C.
Published: January 2014

Black pod syndrome (BPS) causes devastating losses in Lupinus angustifolius (narrow-leafed lupin) crops in Australia, and infection with Bean yellow mosaic virus (BYMV) was suggested as a possible cause. In 2011, an end-of-growing-season survey in which L. angustifolius plants with BPS were collected from six locations in southwestern Australia was done. Tissue samples from different positions on each of these symptomatic plants were tested for BYMV and generic potyvirus by enzyme-linked immunosorbent assay and reverse-transcription polymerase chain reaction (RT-PCR). Detection was most reliable when RT-PCR with generic potyvirus primers was used on tissue taken from the main stem of the plant just below the black pods. Partial coat protein nucleotide sequences from eight isolates from BPS-symptomatic L. angustifolius plants all belonged to the BYMV general phylogenetic group. An initial glasshouse experiment revealed that mechanical inoculation of L. angustifolius plants with BYMV after pods had formed caused pods to turn black. This did not occur when the plants were inoculated before this growth stage (at first flowering) because BYMV infection caused plant death. A subsequent experiment in which plants were inoculated at eight different growth stages confirmed that BPS was only induced when L. angustifolius plants were inoculated after first flowering, when pods had formed. Thus, BYMV was isolated from symptomatic L. angustifolius survey samples, inoculated to and maintained in culture hosts, inoculated to healthy L. angustifolius test plants inducing BPS, and then successfully reisolated from them. As such, Koch's postulates were fulfilled for the hypothesis that late infection with BYMV causes BPS in L. angustifolius plants.
Isoniazid Pharmacokinetics in the Presence of Ofloxacin and Norfloxacin Antibiotics
Authors: Anusiem Chikere A. , Brown Sinyeofori A. , Ezejiofor Ndidi A. , Barikpoar Ebenezer , Orisakwe Orish E.
Published: January 2014

The in vivo effects of norfloxacin (NXC) and ofloxacin (OXC) on isoniazid (INH) pharmacokinetics were investigated in 5 apparently healthy volunteers aged 18–39 years after an informed consent. The study was carried out in 3 phases with an interval drug wash out period of at least 1 week in between the phases. In phase 1 (INH alone), subject received 300 mg (usual adult dose) of INH. In phase 2 (INH + OXC), 300 mg of INH was coadministered with 200 mg of OXC, and in phase 3 (INH + NXC) each received 300 mg of INH together with 400 mg of NXC after 1-week drug wash period. Drugs were taken orally with 350 mL of water after an overnight fast, and the subject fasted 3 hours after drug. Plasma, saliva, and urine concentration of INH were predetermined at zero hour, then hourly until the eighth hour, 12 hours, 24 hours, and finally at 48 hours. The urine samples were further collected at 72 hours after drug(s) administration using validated methods. Various pharmacokinetics parameters were calculated. Various pharmacokinetic parameters of INH significantly differed when administered alone or in combination with OXC or with NXC. The mean saliva to plasma ratio of INH concentration was 0.14. The bioavailability indices of INH in the saliva and plasma were similar in all the groups. NXC and OXC reduced the extent and rate of absorption of INH. The determination of INH levels in saliva may be useful in therapeutic drug monitoring and pharmacokinetic studies.
Spatio-temporal skin strain distributions evoke low variability spike responses in cuneate neurons
Authors: Hayward Vincent , Terekhov Alexander V. , Wong Sheng-Chao , Geborek Pontus , Bengtsson Fredrik , Jörntell Henrik
Published: January 2014

A common method to explore the somatosensory function of the brain is to relate skin stimuli to neurophysiological recordings. However, interaction with the skin involves complex mechanical effects. Variability in mechanically induced spike responses is likely to be due in part to mechanical variability of the transformation of stimuli into spiking patterns in the primary sensors located in the skin. This source of variability greatly hampers detailed investigations of the response of the brain to different types of mechanical stimuli. A novel stimulation technique designed to minimize the uncertainty in the strain distributions induced in the skin was applied to evoke responses in single neurons in the cat. We show that exposure to specific spatio-temporal stimuli induced highly reproducible spike responses in the cells of the cuneate nucleus, which represents the first stage of integration of peripheral inputs to the brain. Using precisely controlled spatio-temporal stimuli, we also show that cuneate neurons, as a whole, were selectively sensitive to the spatial and to the temporal aspects of the stimuli. We conclude that the present skin stimulation technique based on localized differential tractions greatly reduces response variability that is exogenous to the information processing of the brain and hence paves the way for substantially more detailed investigations of the brain's somatosensory system.