bluuebunny/crossref_metadata_2025 huggingface dataset:
Population Genetic and Admixture Analyses of Culex pipiens Complex (Diptera: Culicidae) Populations in California, United States
Authors: Kothera Linda , Nelms Brittany M. , Reisen William K. , Savage Harry M.
Published: August 2013

Microsatellite markers were used to genetically characterize 19 Culex pipiens complex populations from California. Two populations showed characteristics of earlier genetic bottlenecks. The overall FST value and a neighbor-joining tree suggested moderate amounts of genetic differentiation. Analyses using Structure indicated K = 4 genetic clusters: Cx. pipiens form pipiens L., Cx. quinquefasciatus Say, Cx. pipiens form molestus Forskäl, and a group of genetically similar individuals of hybrid origin. A Discriminant Analysis of Principal Components indicated that the latter group is a mixture of the other three taxa, with form pipiens and form molestus contributing somewhat more ancestry than Cx. quinquefasciatus. Characterization of 56 morphologically autogenous individuals classified most as Cx. pipiens form molestus, and none as Cx. pipiens form pipiens or Cx. quinquefasciatus. Comparison of California microsatellite data with those of Cx. pipiens pallens Coquillett from Japan indicated the latter does not contribute significantly to genotypes in California.
Emotions, Sanctions, and Cooperation
Authors: Joffily Mateus , Masclet David , Noussair Charles N , Villeval Marie Claire
Published: August 2013

We use skin conductance responses and self‐reported hedonic valence to study the emotional basis of cooperation and punishment in a social dilemma. We argue that the availability of sanctions sets in motion a “virtuous emotional circle” that accompanies cooperation. Emotional reaction to free riding leads cooperators to apply sanctions. In response, and in addition to the monetary consequences of receiving sanctions, the negative emotions experienced by the free‐riders when punished lead them to increase their subsequent level of cooperation. The outcome is an increased level of cooperation that becomes a new norm. Therefore, emotions sustain both the use of altruistic punishment and cooperation.
An Empirical Study of Suicide Terrorism: A Global Analysis
Authors: Santifort-Jordan Charlinda , Sandler Todd
Published: August 2013

This paper provides the first venue‐based empirical investigation of the number and lethality of suicide terrorist attacks on a global scale. For 1998–2010, we assemble a data set of 2448 suicide terrorist incidents, drawn from the three main terrorist event databases, i.e., International Terrorism: Attributes of Terrorist Events (ITERATE), the Global Terrorism Database (GTD), and RAND. Our data set distinguishes between domestic and transnational suicide terrorist missions. For the quantity of suicide terrorism, we apply zero‐inflated negative binomial panel (country‐year) estimation for country‐specific variables and negative binomial panel estimation for attack‐specific variables. We also present linear regression panel estimations for the impact of suicide terrorism in terms of casualties per attack. Economic, political, and military variables, at times, differentially influenced the two kinds of suicide terrorism. A host of policy conclusions are drawn from the empirical findings.
Multi-model mean nitrogen and sulfur deposition from the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP): evaluation of historical and projected future changes
Authors: Lamarque J.-F. , Dentener F. , McConnell J. , Ro C.-U. , Shaw M. , Vet R. , Bergmann D. , Cameron-Smith P. , Dalsoren S. , Doherty R. , Faluvegi G. , Ghan S. J. , Josse B. , Lee Y. H. , MacKenzie I. A. , Plummer D. , Shindell D. T. , Skeie R. B. , Stevenson D. S. , Strode S. , Zeng G. , Curran M. , Dahl-Jensen D. , Das S. , Fritzsche D. , Nolan M.
Published: August 2013

Abstract. We present multi-model global datasets of nitrogen and sulfate deposition covering time periods from 1850 to 2100, calculated within the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP). The computed deposition fluxes are compared to surface wet deposition and ice core measurements. We use a new dataset of wet deposition for 2000–2002 based on critical assessment of the quality of existing regional network data. We show that for present day (year 2000 ACCMIP time slice), the ACCMIP results perform similarly to previously published multi-model assessments. For this time slice, we find a multi-model mean deposition of approximately 50 Tg(N) yr−1 from nitrogen oxide emissions, 60 Tg(N) yr−1 from ammonia emissions, and 83 Tg(S) yr−1 from sulfur emissions. The analysis of changes between 1980 and 2000 indicates significant differences between model and measurements over the United States but less so over Europe. This difference points towards a potential misrepresentation of 1980 NH3 emissions over North America. Based on ice core records, the 1850 deposition fluxes agree well with Greenland ice cores, but the change between 1850 and 2000 seems to be overestimated in the Northern Hemisphere for both nitrogen and sulfur species. Using the Representative Concentration Pathways (RCPs) to define the projected climate and atmospheric chemistry related emissions and concentrations, we find large regional nitrogen deposition increases in 2100 in Latin America, Africa and parts of Asia under some of the scenarios considered. Increases in South Asia are especially large, and are seen in all scenarios, with 2100 values more than double their 2000 counterpart in some scenarios and reaching > 1300 mg(N) m−2 yr−1 averaged over regional to continental-scale regions in RCP 2.6 and 8.5, ~ 30–50% larger than the values in any region currently (circa 2000). However, sulfur deposition rates in 2100 are in all regions lower than in 2000 in all the RCPs. The new ACCMIP multi-model deposition dataset provides state-of-the-science, consistent and evaluated time slice (spanning 1850–2100) global gridded deposition fields for use in a wide range of climate and ecological studies.
Effects of stratospheric ozone recovery on tropospheric chemistry and air quality
Authors: Zhang H. , Wu S. , Wang Y.
Published: August 2013

Abstract. The stratospheric ozone has decreased greatly since 1980 due to ozone depleting substances (ODSs). As a result of the implementation of the Montreal Protocol and its amendments and adjustments, stratospheric ozone is expected to recover towards its pre-1980 level in the coming decades. We examine the implications of stratospheric ozone recovery for the tropospheric chemistry and ozone air quality with a global chemical transport model (GEOS-Chem). Significant decreases in surface ozone photolysis rates due to stratospheric ozone recovery are simulated. Increases in ozone lifetime by up to 7% are calculated in the troposphere. The global average OH decreases by 1.74% and the global burden of tropospheric ozone increases by 0.78%. The perturbations to tropospheirc ozone and surface ozone show large seasonal and spatial variations. General increases in surface ozone are calculated for each season, with increases by up to 5% for some regions.
Statistical modelling of collocation uncertainty in atmospheric thermodynamic profiles
Authors: Fassò A. , Ignaccolo R. , Madonna F. , Demoz B. B.
Published: August 2013

Abstract. The uncertainty of important atmospheric parameters is a key factor for assessing the uncertainty of global change estimates given by numerical prediction models. One of the critical points of the uncertainty budget is related to the collocation mismatch in space and time among different observations. This is particularly important for vertical atmospheric profiles obtained by radiosondes or LIDAR. In this paper we consider a statistical modelling approach to understand at which extent collocation uncertainty is related to environmental factors, height and distance between the trajectories. To do this we introduce a new statistical approach, based on the heteroskedastic functional regression (HFR) model which extends the standard functional regression approach and allows us a natural definition of uncertainty profiles. Moreover, using this modelling approach, a five-folded uncertainty decomposition is proposed. Eventually, the HFR approach is illustrated by the collocation uncertainty analysis of relative humidity from two stations involved in GCOS reference upper-air network (GRUAN).
Microphytobenthos and benthic macroalgae determine sediment organic matter composition in shallow photic sediments
Authors: Hardison A. K. , Canuel E. A. , Anderson I. C. , Tobias C. R. , Veuger B. , Waters M. N.
Published: August 2013

Abstract. Microphytobenthos and benthic macroalgae play an important role in system metabolism within shallow coastal bays. However, their independent and interactive influences on sediment organic matter (SOM) are not well understood. We investigated the influence of macroalgae and microphytobenthos on SOM quantity and quality in an experimental mesocosm system using bulk and molecular level (total hydrolyzable amino acids, THAA; phospholipid linked fatty acids, PLFA; pigment) analyses. Our experiment used an incomplete factorial design made up of two factors, each with two levels: (1) light (ambient vs. dark) and (2) macroalgae (presence vs. absence of live macroalgae). Over the course of the 42-day experiment, total organic carbon (TOC) and total nitrogen (TN) increased under ambient light by 173 ± 14 and 141 ± 7%, respectively, compared to in the dark (78 ± 29 and 39 ± 22%). THAA comprised a substantial fraction of SOM (~ 16% of TOC, 35% of TN) and followed TOC and TN accumulation patterns. Mole percent composition of the THAA pool indicated that SOM was composed of more labile organic material (e.g., L-glutamic acid, phenylalanine) under ambient light conditions while SOM in dark treatments was more degraded, with higher proportions of glycine and D-alanine. PLFA content, which represents viable biomass, made up ~ 1% of TOC and contained high levels of algal fatty acids in the light, particularly PLFA derived from diatoms. In the presence of microphytobenthos (i.e., light and macroalgae treatments), SOM lability increased, resulting in the observed increases in bacterial PLFA concentrations. Macroalgae, which were added to half of the light treatments, decreased SOM accumulation compared to light treatments without macroalgae, with TOC and TN increasing by only 130 ± 32 and 94 ± 24%, respectively. This decrease likely resulted from shading by macroalgae, which reduced production of microphytobenthos. The presence of macroalgae decreased SOM lability as well, which resulted in diminished buildup of bacterial biomass. By the final day of the experiment, principal component analysis revealed that sediment composition in treatments with macroalgae was more similar to dark treatments and less similar to light treatments without macroalgae. Overall, microphytobenthos and benthic macroalgae fundamentally altered SOM quality and quantity, which may have notable ecological consequences for shallow-water systems such as increased hypoxia/anoxia, sulfide accumulation, enhanced mineralization and/or stimulated denitrification.
River restoration: morphological, hydrological, biogeochemical and ecological changes and challenges
Authors: Schirmer M. , Luster J. , Linde N. , Perona P. , Mitchell E. A. D. , Barry D. A. , Cirpka O. A. , Schneider P. , Vogt T. , Durisch-Kaiser E.
Published: August 2013

Abstract. River restoration is essential as a means to enhance river dynamics, environmental heterogeneity and biodiversity. The underlying processes governing the dynamic changes need to be understood thoroughly to ensure that restoration projects meet their goals. In particular, we need to understand quantitatively how hydromorphological variability relates to ecosystem functioning and services, biodiversity and (ground)water quality in restored river corridors. Here, we provide a short overview on the literature and present a study of a restored river corridor in Switzerland combining physical, chemical, and biological observations with modeling. The results show complex spatial patterns of bank infiltration, habitat-type, biotic communities and biogeochemical processes. In particular, we found an increase in taxonomic and functional diversity for earthworms, testate amoebae and bacteria in the restored part of the river. This complexity is driven by river hydrology and morphodynamics, which are in turn actively coupled to riparian vegetation processes. Given this complexity and the multiple constraints on the uses and management of floodplains, a multi-disciplinary approach is needed to monitor the success of restoration measures and to make recommendations for future restoration projects.
Generalized combination equations for canopy evaporation under dry and wet conditions
Authors: Lhomme J. P. , Montes C.
Published: August 2013

Abstract. The formulation of canopy evaporation is investigated on the basis of the combination equation derived from the Penman equation. All the elementary resistances (surface and boundary layer) within the canopy are taken into account and the exchange surfaces are assumed to be subject to the same vapour pressure deficit at canopy source height. This development leads to generalized combination equations: one for completely dry canopies and the other for partially wet canopies. These equations are rather complex because they involve the partitioning of available energy within the canopy and between the wet and dry surfaces. By making some assumptions and approximations, they can provide simpler equations similar to the common Penman–Monteith model. One of the basic assumptions of this down-grading process is to consider that the available energy intercepted by the different elements making up the canopy is uniformly distributed and proportional to their respective area. Despite the somewhat unrealistic character of this hypothesis, it allows one to retrieve the simple formulations commonly and successfully used up to now. Numerical simulations are carried out by means of a simple one-dimensional model of the vegetation–atmosphere interaction to compare the complete formulations with the simpler ones and to assess the concept of excess resistance.
Changes in ventilation of the Mediterranean Sea during the past 25 yr
Authors: Schneider A. , Tanhua T. , Roether W. , Steinfeldt R.
Published: August 2013

Abstract. The Mediterranean Sea has a fast overturning circulation and the deep water masses are well ventilated in comparison to the deep waters of the world ocean. Significant changes in the overturning circulation has been observed during the last few decades, the most prominent phenomena being the Eastern Mediterranean Transient (EMT) in the early 1990s and the Western Mediterranean Transit (WMT) near the mid of the decade following. During both of these events unusually large amounts of deep water were formed, and in the case of the EMT, the deep water formation area shifted from the Adriatic to the Aegean Sea. This variability is important to understand and to monitor, because ventilation is the main process to propagate surface perturbations, such as uptake of anthropogenic CO2, into the ocean interior. Here we synthesize a unique collection of transient tracer (CFC-12, SF6 and tritium) data from nine cruises conducted between 1987 and 2011 and use these data to determine temporal variability of Mediterranean ventilation. We also discuss biases and technical problems with transient tracer-based ages arising from their different input histories over time; particularly in the case of time-dependent ventilation. We observe a period of stagnation in the deep eastern (Levantine) basin after it was ventilated by the EMT so that the age of the deep water is increasing with time. In the Ionian Sea, on the other hand, we see evidence of increased ventilation after year 2001, indicating the restarted deep water formation in the Adriatic Sea. This is also reflected in the increasing age of the Cretan Sea deep water and decreasing age of Adriatic Sea deep water since the end of the 1980s. In the western Mediterranean deep basin we see the massive input of recently ventilated waters during the WMT. This signal is not yet apparent in the Tyrrhenian Sea, where the ventilation seems to be fairly constant since the EMT. Also the western Alboran Sea does not show any temporal trends in ventilation.
Spectral reflectance of solar light from dirty snow: a simple theoretical model and its validation
Authors: Kokhanovsky A.
Published: August 2013

Abstract. A simple analytical equation for the snow albedo as the function of snow grain size, soot concentration, and soot mass absorption coefficient is presented. This simple equation can be used in climate models to assess the influence of snow pollution on snow albedo. It is shown that the squared logarithm of the albedo (in the visible) is directly proportional to the soot concentration. A new method of the determination of the soot mass absorption coefficient in snow is proposed. The equations derived are applied to a dusty snow layer as well.
Dialogue-based teaching: The art museum as a learning space
Authors: Clarkin-Phillips Jeanette
Published: August 2013

Book review: Olga Dysthe, Nana Bernhardt & Line Esbjørn (2013). Dialogue-based teaching. The art museum as a learning space. Copenhagen, Denmark: Skoletjenesten.
Los “Demetrios”: ¿trotskistas, peronistas, nazis?
Authors: Denaday Juan Pedro
Published: August 2013

O “Encuadramiento” da Juventude Peronista foi um dos grupos políticos mais importantes dos jovens ativistas em fervimento durante a segunda metade da década de 1960 e a primeira de 1970. Uma experiência política e intelectual ausente na maior parte da historiografia do período, a partir de meados de 2012 surgiram os primeiros estudos. Os "Demetrios" definiam suas ações no que eles chamaram de "lealdade objetiva e doutrinária" ao General Perón, fato que nos permite localizá-los dentro do peronismo "ortodoxo" num caminho semelhante ao da Guarda de Ferro. No entanto, os seus origens e formulações teórico-políticas fizeram com que receberam apelidos tão diferentes, que no jargão militante, escutávam-se alguns tais como "trotskistas" até "hitlerianos". Neste trabalho analizamos essa trajetória política enfocando nos aspectos ideológicos. Para isso, estudamos suas origens nessa transição do trotskismo ao peronismo, suas considerações próprias sobre o fenômeno nazista e sua localização política e ideológica em 1973. Esse ano foi um momento chave de definições dentro da Juventude Peronista, que incluiu uma discussão e uma disputa com a Tendência Revolucionária sobre o significado do "socialismo nacional" avalizado publicamente por Perón anos antes.
A historiografia isidoriana: teologia e política
Authors: Feldman Sergio Alberto
Published: August 2013

Isidoro de Sevilha é um bispo visigodo da Antiguidade Tardia, autor de vasta obra exegética, teológica e também historiográfica. Este artigo visa a entender a função e o objetivo da obra historiográfica isidoriana, no contexto da evangelização da Península Ibérica e da busca de legitimação e fortalecimento da Monarquia católica, como aliada da Igreja. A escrita da história em Isidoro tem motivações diversas, sendo moldada a partir de interpretações teológicas e pretendendo gerar modelos comportamentais aos reis, aos nobres e clérigos, e aos demais setores sociais. O sentido pedagógico se sobressai, junto com a visão teleológica.
Sobre os meios e modos de fazer jornalismo na Primeira República: Lima Barreto entre a história e a ficção
Authors: Botelho Denilson
Published: August 2013

Este artigo consiste na análise de um conto de Lima Barreto (1881-1922), intitulado “O jornalista”, publicado na revista Souza Cruz, em 1921, a partir do qual se discute e examina os meios e modos de fazer jornalismo na Primeira República. Tomando a literatura como fonte e como um tipo de documento, investiga-se o significado dessa publicação, bem como sua relação com outros textos do autor, a fim de perceber o quanto são capazes de revelar sobre as lutas travadas no universo da imprensa. Trata-se de resultados parciais de pesquisa desenvolvida no campo da história social da cultura, tendo como referenciais teóricos as contribuições de E. P. Thompson e Raymond Williams.
The Importance of Consumers’ Knowledge About Food Quality, Labeling and Safety in Food Choice
Authors: Grujic Slavica , Grujic Radoslav , Petrovic Dorde , Gajic Jelena
Published: August 2013

With the aim to investigate existence of difference between responses of selected groups of young consumers representatives toward information associated with knowledge about food quality, labeling, safety and conditions of the product use, the results of survey were analyzed crossing the groups of consumers regarding: (1) education and (2) gender, with the other variables: (i) information related to food quality, labeling and food safety; (ii) information related to food safety; (iii) information associated with individual experience in food purchasing, preparing and consuming. The questionnaire offered answers with three grade of importance. Our research showed that groups of students formed on the basis of their education and gender, in our survey considered as representatives of young adults, had different interest for selected set of information included in the statements connected with food quality, safety and food choice. The results showed that there is a need for better informing and education of consumers about food quality and safety, labels and labeling, and how to use and interpret labels content. The results of research represent a qualitative set of information related to the food preference, which could be useful for creation and development guidelines for consumers’ better informing and education.
An Application of Gröbner Basis in Differential Equations of Physics
Authors: Chaharbashloo Mohammad Saleh , Basiri Abdolali , Rahmany Sajjad , Zarrinkamar Saber
Published: August 2013

We apply the Gröbner basis to the ansatz method in quantum mechanics to obtain the energy eigenvalues and the wave functions in a very simple manner. There are important physical potentials such as the Cornell interaction which play significant roles in particle physics and can be treated via this technique. As a typical example, the algorithm is applied to the semi-relativistic spinless Salpeter equation under the Cornell interaction. Many other applications of the idea in a wide range of physical fields are listed as well.
Exotic Resonant States for One-Dimensional Twin Complex Square Potentials
Authors: Grama Cornelia , Grama Nicolae , Zamfirescu Ioan , Hulubei Horia
Published: August 2013

The natural modes for one-dimensional (1D) twin square potentials of complex strength g are studied. A global analysis of the natural modes based on the construction of the Riemann surfaces RI
g and RII
g of the multiple valued function k = k(g), where k(g) defines the poles of the transmission coefficient, is done. To each nonradiative or radiative mode a sheet of the Riemann surface is associated. All the natural modes of the system are identified and treated in a unified way. New classes of resonant state poles with exotic properties are identified on the k-plane images of the sheets of RI
g and RII
g and the properties of the exotic modes are studied. The traversal time through the 1D twin square potentials is analysed. Subluminal and superluminal traversal times are evidenced. An approximate formula for the frequencies k for which the maximal superluminal velocities are gained as a function of the potential parameters is given.
The privacy implications of online bonding, bridging and boundary crossing: An experimental study using emoticons in a social network map
Authors: Guan Xiaoyi , Tate Mary
Published: August 2013

This paper describes a study of privacy behaviour in situations of strong (bonding), weak and latent (bridging) and “boundary-crossing” relationships in online social network sites (SNS). An experimental study was conducted utilising screen capture, diaries, and a final interview. An innovative aspect of the experiment was the use of emoticons in a social network visualisation tool to represent emotional status. The contribution of the study is two-fold. We extend previous research with a more nuanced understanding of privacy concerns and behaviours in SNS in the context of different social ties. We also demonstrate an innovative research design using a social network visualization tool, and show the value of SNS visualization for researchers and social network users.
Can e-mentoring take the "gender" out of mentoring?
Authors: Rockwell Brittany V. , Leck Joanne D. , Elliott Catherine J.
Published: August 2013

Mentoring has been identified as a key strategy for career development and organizational advancement, and has been argued to be indispensable for women to succeed. E-mentoring has increased in popularity as a means of reducing some of the challenges associated with being mentored by men. Numerous studies conducted on formal mentoring programs have concluded that there are serious implications to consider in traditional cross-gendered mentoring schemes. A sample of six mentees and seven mentors (three female and four male) were interviewed after a year-long e-mentoring program was created to promote women to leadership roles within the Information Technology (IT) sector. The paper explores whether gender-biases encountered in traditional mentoring schemes are transcended when using an e-mentoring platform. Results from this qualitative study suggest that mentor gender still impacts the mentoring relationship even in a virtual environment. The study’s findings indicated male mentors tended to be more methodological in solving problems with their mentees, unlike female mentors who took a more indirect approach. Further, female mentors improved their mentee’s confidence through encouragement and relating to their mentee on a more personal level, a practice often avoided by their male counterparts. A summary of these findings is provided below, followed by a detailed discussion of the results and a section offering possible future research avenues to explore.
Delays in the Regulatory Schedule From Budgets and Others
Authors: Roberson J. Alan
Published: August 2013

There isn't much of the year left ‐ just four months ‐ so I'm recommending patience from the water community through some delays and uncertainties. At this point in 2013, it appears that the following four regulatory actions initially thought to be coming out in 2013 are going to be delayed until at least 2014: preliminary third regulatory determination, proposed Long Term Lead and Copper Rule (LT‐LCR) revisions, proposed Perchlorate Rule, and proposed carcinogenic Volatile Organic Compound (cVOC) Rule.
Cities of the Future: Where Will the Water Come From?
Authors: Richter Brian
Published: August 2013

Thousands of cities around the world are experiencing water shortages on a regular basis. These water‐stressed cities are finding it extremely difficult and expensive to secure the additional water supplies needed to support their growth. Their best hope might be to form partnerships with farmers; by helping to reduce water consumption on farms, water can be freed up for use in the city. Urban water conservation is important as well.
Utility's Award‐Winning Initiative Unites Workforce and Community
Authors: Weindorf Blake
Published: August 2013

The Little Rock area in Arkansas has a history of overcoming cultural challenges, such as the racial integration of Little Rock's Central High School in 1957. In the same spirit, when the Little Rock and North Little Rock water utilities merged in 2001, inclusiveness and integration were priorities, and a new page in Arkansas water history was written.
Potable reuse: Developing a new source of water for san Diego
Authors: Steirer Marsi A. , Thorsen Danielle
Published: August 2013

Although much work lies ahead, San Diego, Calif., is on the path toward developing a new, local, and reliable source of water through potable reuse.
Introducing Volume 19: Developing Mathematical Thinkers
Authors: Wohlhuter Kay A.
Published: August 2013

Introductory remarks by the MTMS Editorial Panel launch the 2013–2014 volume year.
Informing Practice: I-THINK I Can Problem Solve
Authors: Lynch Sararose D. , Lynch Jeremy M. , Bolyard Johnna
Published: August 2013

Students access the THINK framework that involves prompts exploring talk, how, identify, notice, and keep.
Mathematical Explorations: Understanding Geometry and Measurement through Service-Learning
Authors: Gillmor Susan C. , Rabinowicz Samantha A.
Published: August 2013

A service-learning activity that is tied to geometry concludes with a donation to a community food drive.
Math for Real: Now We're Cooking
Authors: Chandler Brendan
Published: August 2013

A recipe-costing sheet provides the real-life tie-in to this computation activity.
La construction discursive de l’identité francophone en Acadie ou « comment être francophone à partir des marges » ?
Authors: Arrighi Laurence , Boudreau Annette
Published: August 2013

L’article met l’accent sur l’apport des discours « d’autorité » dans la construction de l’idéologie du français unique, très présent dans la francophonie. Émanant des « centres » linguistiques et souvent considérés comme référence et source légitime du savoir, ces discours « savants » jouent un rôle fondamental dans la construction des représentations et idéologies linguistiques, notamment dans les milieux minoritaires, où l’examen théorique et épistémologique des « objets » minoritaires est souvent négligé au profit d’études plus empiriques. L’article interroge notamment le rôle que joue le linguiste en milieu minoritaire étant donné que ce dernier contribue parfois, à son insu, à stéréotyper certaines pratiques des francophones.
ATP-dependent chromatin assembly is functionally distinct from chromatin remodeling
Authors: Torigoe Sharon E , Patel Ashok , Khuong Mai T , Bowman Gregory D , Kadonaga James T
Published: August 2013

Chromatin assembly involves the combined action of ATP-dependent motor proteins and histone chaperones. Because motor proteins in chromatin assembly also function as chromatin remodeling factors, we investigated the relationship between ATP-driven chromatin assembly and chromatin remodeling in the generation of periodic nucleosome arrays. We found that chromatin remodeling-defective Chd1 motor proteins are able to catalyze ATP-dependent chromatin assembly. The resulting nucleosomes are not, however, spaced in periodic arrays. Wild-type Chd1, but not chromatin remodeling-defective Chd1, can catalyze the conversion of randomly-distributed nucleosomes into periodic arrays. These results reveal a functional distinction between ATP-dependent nucleosome assembly and chromatin remodeling, and suggest a model for chromatin assembly in which randomly-distributed nucleosomes are formed by the nucleosome assembly function of Chd1, and then regularly-spaced nucleosome arrays are generated by the chromatin remodeling activity of Chd1. These findings uncover an unforeseen level of specificity in the role of motor proteins in chromatin assembly.
Assembly, remodelled
Authors: Bouazoune Karim , Kingston Robert E
Published: August 2013

Biochemical assays reveal that nucleosome maturation and chromatin remodelling by the motor protein Chd1 are distinct, separable enzymatic activities.
Characterization of Arabidopsis aldolases AtFBA4, AtFBA5, and their inhibition by morin and interaction with calmodulin
Authors: Symonds Kyle , Smith Milena A. , Esme Oona , Plaxton William C. , Snedden Wayne A.
Published: July 2024

Fructose bisphosphate aldolases (FBAs) catalyze the reversible cleavage of fructose 1,6‐bisphosphate into dihydroxyacetone phosphate and glyceraldehyde 3‐phosphate. We analyzed two previously uncharacterized cytosolic Arabidopsis FBAs, AtFBA4 and AtFBA5. Based on a recent report, we examined the interaction of AtFBA4 with calmodulin (CaM)‐like protein 11 (AtCML11). AtFBA4 did not bind AtCML11; however, we found that CaM bound AtFBA5 in a Ca2+‐dependent manner with high specificity and affinity (KD ~ 190 nm) and enhanced its stability. AtFBA4 and AtFBA5 exhibited Michaelis–Menten kinetics with Km and Vmax values of 180 μm and 4.9 U·mg−1 for AtFBA4, and 6.0 μm and 0.30 U·mg−1 for AtFBA5, respectively. The flavonoid morin inhibited both isozymes. Our study suggests that Ca2+ signaling and flavanols may influence plant glycolysis/gluconeogenesis.
Hypoxic–Normoxic Crosstalk Activates Pro‐Inflammatory Signaling in Human Cardiac Fibroblasts and Myocytes in a Post‐Infarct Myocardium on a Chip
Authors: Khalil Natalie N. , Rexius‐Hall Megan L. , Gupta Divya , McCarthy Liam , Verma Riya , Kellogg Austin C. , Takamoto Kaelyn , Xu Maryann , Nejatpoor Tiana , Parker Sarah J. , McCain Megan L.
Published: July 2024

Myocardial infarctions locally deprive myocardium of oxygenated blood and cause immediate cardiac myocyte necrosis. Irreparable myocardium is then replaced with a scar through a dynamic repair process that is an interplay between hypoxic cells of the infarct zone and normoxic cells of adjacent healthy myocardium. In many cases, unresolved inflammation or fibrosis occurs for reasons that are incompletely understood, increasing the risk of heart failure. Crosstalk between hypoxic and normoxic cardiac cells is hypothesized to regulate mechanisms of repair after a myocardial infarction. To test this hypothesis, microfluidic devices are fabricated on 3D printed templates for co‐culturing hypoxic and normoxic cardiac cells. This system demonstrates that hypoxia drives human cardiac fibroblasts toward glycolysis and a pro‐fibrotic phenotype, similar to the anti‐inflammatory phase of wound healing. Co‐culture with normoxic fibroblasts uniquely upregulates pro‐inflammatory signaling in hypoxic fibroblasts, including increased secretion of tumor necrosis factor alpha (TNF‐α). In co‐culture with hypoxic fibroblasts, normoxic human induced pluripotent stem cell (hiPSC)‐derived cardiac myocytes also increase pro‐inflammatory signaling, including upregulation of interleukin 6 (IL‐6) family signaling pathway and increased expression of IL‐6 receptor. Together, these data suggest that crosstalk between hypoxic fibroblasts and normoxic cardiac cells uniquely activates phenotypes that resemble the initial pro‐inflammatory phase of post‐infarct wound healing.
Copper‐Based Composites Nanoparticles Improve Triple‐Negative Breast Cancer Treatment with Induction of Apoptosis‐Cuproptosis and Immune Activation
Authors: Wang Ning , Liu Yichao , Peng Dezhou , Zhang Qiyu , Zhang Zhibo , Xu Lina , Yin Lianhong , Zhao Xuerong , Lu Zhi , Peng Jinyong
Published: July 2024

The synergistic effect of apoptosis and cuproptosis, along with the activation of the immune system, presents a promising approach to enhance the efficacy against triple‐negative breast cancer (TNBC). Here, two prodrugs are synthesized: a reactive oxygen species (ROS)‐responsive prodrug PEG‐TK‐DOX and a glutathione (GSH)‐responsive prodrug PEG‐DTPA‐SS‐CPT. These prodrugs are self‐assembled and chelated Cu2+ to prepare nanoparticle PCD@Cu that simultaneously loaded doxorubicin (DOX), camptothecin (CPT), and Cu2+. The elevated levels of ROS and GSH in TNBC cells disrupted the PCD@Cu structure, leading to the release of Cu+, DOX, and CPT and the depletion of GSH. DOX and CPT triggered apoptosis with immunogenic cell death (ICD) in TNBC cells. Simultaneously, PCD@Cu downregulated the expression of copper transporting ATPase 2 (ATP7B), causing a significant accumulation of copper ions in TNBC cells. This further induced the aggregation of lipoylated dihydrolipoamide S‐acetyltransferase (DLAT) and downregulation of iron‐sulfur (Fe‐S) cluster proteins, ultimately leading to cuproptosis and ICD in TNBC. In vitro and in vivo experiments confirmed that PCD@Cu induced apoptosis and cuproptosis in TNBC and activated the immune system, demonstrating strong anti‐tumor capabilities. Moreover, PCD@Cu exhibited an excellent biosafety profile. Overall, this study provides a promising strategy for effective TNBC therapy.
Infrared‐Transparent Semiconductor Membranes for Electromagnetic Interference Shielding of Millimeter Waves
Authors: Renteria Emma J. , Heileman Grant D. , Neely Jordan P. , Addamane Sadhvikas J. , Rotter Thomas J. , Balakrishnan Ganesh , Christodoulou Christos G. , Cavallo Francesca
Published: July 2024

It is demonstrated that single‐crystalline and highly doped GaAs membranes are excellent candidates for realizing infrared‐transparent shields of electromagnetic interference at millimeter frequencies. Measured optical transmittance spectra for the semiconductor membranes show resonant features between 750 and 2500 nm, with a 100% maximum transmittance. The shielding effectiveness of the membranes is extracted from measured scattering parameters between 65 and 85 GHz. Selected GaAs membranes and membranes/polyamide films exhibit shielding effectiveness ranging from 22 to 40 dB, which are suitable values to ensure the safe operation of infrared devices for commercial applications. Theoretical calculations based on a plane wave model show that the interplay of primary reflection and multiple internal reflections of the radio‐frequency waves results in broadband shielding capabilities of the membrane between 10 and 300 GHz.
Anomalous Radiative Transfer in Heterogeneous Media
Authors: Tommasi Federico , Pattelli Lorenzo , Cavalieri Stefano , Fini Lorenzo , Paolucci Michela , Pini Ernesto , Sassaroli Angelo , Martelli Fabrizio
Published: July 2024

Monte Carlo (MC) simulations are the gold standard for describing various transport phenomena and have largely contributed to the understanding of these processes. However, while their implementation for classical transport governed by exponential step‐length distributions is well‐established, widely accepted approaches are still lacking for the more general class of anomalous transport phenomena. In this work, a set of rules for performing MC simulations in anomalous diffusion media is identified, which is also applicable in the case of finite‐size geometries and/or heterogeneous inclusions. The results are presented in the context of radiative transfer, however their implications extend to all types of anomalous transport. The proposed set of rules exhibits full compatibility with the pathlength invariance property for random trajectories, and with the important radiometric concept of fluence. Additionally, it reveals the counter‐intuitive possibility of introducing interfaces between independent subdomains with identical properties, which arise from the fact that non‐exponential step‐length distributions have a “memory” that can in principle be reset when traversing a boundary. These results have far‐reaching consequences not just for the physical interpretation of the corrections required to handle these discontinuities, but also for their experimental verification, due to their expected effects on the observable pathlength distributions.
Unraveling the Roles of Switching and Relaxation Times in Volatile Electrochemical Memristors to Mimic Neuromorphic Dynamical Features
Authors: Dutta Mrinmoy , Brivio Stefano , Spiga Sabina
Published: July 2024

Computing through ensembles of interacting dynamical elements is the next frontier of the diverse field of neuromorphic computing. Spiking neural networks are one of the possible examples. Computation through dynamics and through time requires the development of novel technologies for devices with rich dynamics. Among the various candidates, the most promising ones are volatile electrochemical memristive systems that switch from high to low resistance state by voltage application and self‐recover the high resistance state after a tunable relaxation time. Such devices can perform a wide variety of computational primitives. However, a clear comprehensive picture of their possible dynamics and their physical interpretation is still missing. In the present manuscript, prototypical electrochemical silver/silicon oxide/platinum (Ag/SiOx/Pt) memristive devices are characterized to identify dynamical aspects, like integrative effects and stochastic switching. Integrative effects are evidenced both in high and low resistance states, associated to wake‐up phase and cumulative switching. All the dynamical aspects are related to characteristic switching times and relaxation times, and with reference to the electrochemical and physical processes involved in device operation. The various dynamical aspects are linked to short‐term memory effects and basic temporal processing functions based on paired‐pulse effects that are relevant for neuromorphic applications.
Striking genetic homogeneity in the widespread South American bracken
Authors: Yañez Agustina , Kinosian Sylvia P. , Ponce M. Mónica , Gutierrez Diego G. , Schwartsburd Pedro B. , Sundue Michael , Wolf Paul G.
Published: July 2024

Premise

Bracken (Pteridium, Dennstaedtiaceae) is a cosmopolitan genus of aggressive disturbance colonizers that are toxic to agricultural livestock. The taxonomy of Pteridium has been treated in multiple schemes, ranging from one to six species worldwide, with numerous subspecies and varieties. Recent work has focused on the worldwide distribution and systematics of the bracken fern, but South America has been poorly represented. We present the first continent‐wide sampling and analysis of Pteridium esculentum, a Southern Hemisphere diploid species.

Methods

Within South America, P. esculentum has several morphotypes, distinguished into subspecies by variation in indument and lamina architecture. We used double digest restriction site‐associated DNA sequencing (ddRADSeq) to assess the phylogenetic relationships of P. esculentum subspecies.

Results

We found a striking genetic homogeneity in the species, being able to support only two morphotypes from molecular data: P. e. arachnoideum and P. e. campestre. We had high confidence for shallow and deep phylogenetic relationships, but less support for relationships among crown groups.

Conclusions

We describe an east‐west geographic pattern that would explain the relationships between populations; and, in contrast to previous studies, we detected differences with P. esculentum from Australia. These results will lay the foundations for studying variations in this species' behavior as a weed, as well as its impact on the production of agricultural livestock in South America.
Inequalities in accelerated cognitive decline: Resolving observational window bias using nested non‐linear regression
Authors: Clouston Sean A. P. , Hanes Douglas W. , Smith Dylan M. , Richmond Lauren L. , Richards Marcus , Link Bruce
Published: July 2024

INTRODUCTION

Limited observational windows lead to conflicting results in studies examining educational differences in Alzheimer's disease and related dementias (ADRD) risk, due to observational window bias relative to onset of accelerated cognitive decline. This study tested a novel model to address observational window bias and tested for the presence and sources of disparities in accelerated cognitive declines due to ADRD.

METHODS

The sample examined 167,314 cognitive assessments from 32,441 Health and Retirement Study participants. We implemented a parametric non‐linear nested longitudinal regression and reported multivariable‐adjusted nodal incidence ratios (aNIR).

RESULTS

University degrees were associated with lower incidence (aNIR = 0.253, 95% confidence interval [CI] = [0.221 to 0.289], p < 0.001), while black participants had a higher incidence (aNIR = 1.995, [1.858 to 2.141], p < 0.001) of accelerated cognitive decline, adjusting for demographic, sociobehavioral, and medical risk factors. Sex‐stratified analyses identified diminished educational returns for women and increased incidence among minoritized women.

DISCUSSION

Addressing observational window bias reveals large social inequalities in the onset of accelerated cognitive declines indicative of ADRD.

Highlights

This study identifies observational window bias as a source of conflicting results among previous studies of educational achievement in Alzheimer's disease and related dementias (ADRD) disparities.

The study locates preclinical accelerated cognitive decline, which is indicative of ADRD while occurring 10+ years prior to symptom onset, as a site to study ADRD disparities that mitigates observational window bias.

A novel method, nested non‐linear regression, is developed to test for differences in the onset of accelerated cognitive decline.

Educational and racial/ethnic disparities are demonstrated in the onset of accelerated cognitive decline, as are their intersecting differences with sex/gender.
Assessing cognitive impairment and disability in older adults through the lens of whole brain white matter patterns
Authors: Roh Hyun Woong , Chauhan Nishant , Seo Sang Won , Choi Seong Hye , Kim Eun‐Joo , Cho Soo Hyun , Kim Byeong C. , Choi Jin Wook , An Young‐Sil , Park Bumhee , Lee Sun Min , Moon So Young , Nam You Jin , Hong Sunhwa , Son Sang Joon , Hong Chang Hyung , Lee Dongha
Published: July 2024

INTRODUCTION

This study aimed to explore the potential of whole brain white matter patterns as novel neuroimaging biomarkers for assessing cognitive impairment and disability in older adults.

METHODS

We conducted an in‐depth analysis of magnetic resonance imaging (MRI) and amyloid positron emission tomography (PET) scans in 454 participants, focusing on white matter patterns and white matter inter‐subject variability (WM‐ISV).

RESULTS

The white matter pattern ensemble model, combining MRI and amyloid PET, demonstrated a significantly higher classification performance for cognitive impairment and disability. Participants with Alzheimer's disease (AD) exhibited higher WM‐ISV than participants with subjective cognitive decline, mild cognitive impairment, and vascular dementia. Furthermore, WM‐ISV correlated significantly with blood‐based biomarkers (such as glial fibrillary acidic protein and phosphorylated tau‐217 [p‐tau217]), and cognitive function and disability scores.

DISCUSSION

Our results suggest that white matter pattern analysis has significant potential as an adjunct neuroimaging biomarker for clinical decision‐making and determining cognitive impairment and disability.

Highlights

The ensemble model combined both magnetic resonance imaging (MRI) and amyloid positron emission tomography (PET) and demonstrated a significantly higher classification performance for cognitive impairment and disability.

Alzheimer's disease (AD) revealed a notably higher heterogeneity compared to that in subjective cognitive decline, mild cognitive impairment, or vascular dementia.

White matter inter‐subject variability (WM‐ISV) was significantly correlated with blood‐based biomarkers (glial fibrillary acidic protein and phosphorylated tau‐217 [p‐tau217]) and with the polygenic risk score for AD.

White matter pattern analysis has significant potential as an adjunct neuroimaging biomarker for clinical decision‐making processes and determining cognitive impairment and disability.
Efficient and Stable NIR‐II Phosphorescence of Metallophilic Molecular Oligomers for In Vivo Single‐Cell Tracking and Time‐Resolved Imaging
Authors: Shi Ben , Zhang Lu , Yan Kui , Ming Jiang , Chen Zi‐Han , Chen Ying , He Haisheng , Zhang Hongxin , Wang Lixin , Wang Shangfeng , Zhang Fan
Published: July 2024

Molecular phosphorescence in the second near‐infrared window (NIR‐II, 1000–1700 nm) holds promise for deep‐tissue optical imaging with high contrast by overcoming background fluorescence interference. However, achieving bright and stable NIR‐II molecular phosphorescence suitable for biological applications remains a formidable challenge. Herein, we report a new series of symmetric isocyanorhodium(I) complexes that could form oligomers and exhibit bright, long‐lived (7–8 μs) phosphorescence in aqueous solution via metallophilic interaction. Ligand substituents with enhanced dispersion attraction and electron‐donating properties were explored to extend excitation/emission wavelengths and enhanced stability. Further binding the oligomers with fetal bovine serum (FBS) resulted in NIR‐II molecular phosphorescence with high quantum yields (up to 3.93 %) and long‐term stability in biological environments, enabling in vivo tracking of single‐macrophage dynamics and high‐contrast time‐resolved imaging. These results pave the way for the development of highly‐efficient NIR‐II molecular phosphorescence for biomedical applications.