bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessing vegetation structure and ANPP dynamics in a grassland–shrubland Chihuahuan ecotone using NDVI–rainfall relationships
Authors: Moreno-de las Heras M. , Díaz-Sierra R. , Turnbull L. , Wainwright J.
Published: May 2015

Abstract. Climate change and the widespread alteration of natural habitats are major drivers of vegetation change in drylands. In the Chihuahuan Desert, large areas of grasslands dominated by perennial grass species have transitioned over the last 150 years to shrublands dominated by woody species, accompanied by accelerated water and wind erosion. Multiple mechanisms drive the shrub-encroachment process, including precipitation variations, land-use change, and soil erosion–vegetation feedbacks. In this study, using a simple ecohydrological modelling framework, we show that herbaceous (grasses and forbs) and shrub vegetation in drylands have different responses to antecedent precipitation due to functional differences in plant-growth and water-use patterns. Therefore, shrub encroachment may be reflected in the analysis of landscape-scale vegetation–rainfall relationships. We analyse the structure and dynamics of vegetation at an 18 km2 grassland–shrubland ecotone in the northern edge of the Chihuahuan Desert (McKenzie Flats, Sevilleta National Wildlife Refuge, NM, USA) by investigating the relationship between decade-scale (2000–2013) records of remotely sensed vegetation greenness (MODIS NDVI) and antecedent rainfall. NDVI–rainfall relationships show a high sensitivity to spatial variations on dominant vegetation types across the grassland–shrubland ecotone, and provide biophysical criteria to (a) classify landscape types as a function of the spatial distribution of dominant vegetation and to (b) decompose the NDVI signal into partial components of annual net primary production (ANPP) for herbaceous vegetation and shrubs. Analysis of remotely sensed ANPP dynamics across the study site indicates that plant growth for herbaceous vegetation is particularly synchronized with monsoonal summer rainfall. For shrubs, ANPP is better explained by winter plus summer precipitation, overlapping the monsoonal period (June–September) of rain concentration. Our results suggest that shrub encroachment was not particularly active in this Chihuahuan ecotone for the period 2000–2013. However, future changes in the amount and temporal pattern of precipitation (i.e. reductions in monsoonal summer rainfall and/or increases in winter precipitation) may enhance the shrub-encroachment process, particularly in the face of expected upcoming increases in aridity for desert grasslands of the southwestern USA.
Seasonal dynamics of organic carbon and metals in thermokarst lakes from the discontinuous permafrost zone of western Siberia
Authors: Manasypov R. M. , Vorobyev S. N. , Loiko S. V. , Kritzkov I. V. , Shirokova L. S. , Shevchenko V. P. , Kirpotin S. N. , Kulizhsky S. P. , Kolesnichenko L. G. , Zemtzov V. A. , Sinkinov V. V. , Pokrovsky O. S.
Published: May 2015

Abstract. Despite relatively good knowledge of the biogeochemistry of Siberian thermokarst lakes during summer base flow, their seasonal dynamics remains almost unexplored. This work describes the chemical composition of ~130 thermokarst lakes ranging in size from a few m2 to several km2, located in the discontinuous permafrost zone. Lakes were sampled during spring flood, just after the ice break (early June), the end of summer (August), the beginning of ice formation (October) and during the full freezing season in winter (February). The lakes larger than 1000 m2 did not exhibit any statistically significant control of the lake size on dissolved organic carbon (DOC), the major and trace element concentrations over three major open water seasons. On the annual scale, the majority of dissolved elements including organic carbon increased their concentration from 30 to 500%, with a statistically significant (p < 0.05) trend from spring to winter. The concentrations of most trace elements (TEs) increased in the order spring > summer > autumn > winter. The ice formation in October included several stages: first, surface layer freezing followed by crack (fissure) formation with unfrozen water from the deeper layers spreading over the ice surface. This water was subsequently frozen and formed layered ice rich in organic matter. As a result, the DOC and metal (Mn, Fe, Ni, Cu, Zn, As, Ba and Pb) concentrations were highest near the surface of the ice column (0 to 20 cm) and decreased by a factor of 2 towards the bottom. The main implications of discovered freeze-driven solute concentrations in thermokarst lake waters are enhanced colloidal coagulation and removal of dissolved organic matter and associated insoluble metals from the water column to the sediments. The measured distribution coefficients of a TE between amorphous organo-ferric coagulates and lake water (<0.45 μm) were similar to those reported earlier for Fe-rich colloids and low molecular weight (<1 kDa, or <1–2 nm) fractions of thermokarst lake waters, suggesting massive co-precipitation of TE with amorphous Fe oxyhydroxide stabilized by organic matter. Although the concentration of most elements was lowest in spring, this period of maximal water coverage of land created a significant reservoir of DOC and soluble metals in the water column that can be easily mobilized to the hydrological network. The highest DOC concentration observed in the smallest (<100 m2) water bodies in spring suggests their strongly heterotrophic status and, therefore, a potentially elevated CO2 flux from the lake surface to the atmosphere.
Radiocarbon isotopic evidence for assimilation of atmospheric CO2 by the seagrass Zostera marina
Authors: Watanabe K. , Kuwae T.
Published: May 2015

Abstract. Submerged aquatic vegetation assimilates dissolved inorganic carbon (DIC) in the water column as a carbon source across its thin cuticle layer. However, it is expected that marine macrophytes also use atmospheric CO2 when exposed to the air during low tide, although assimilation of atmospheric CO2 has never been quantitatively evaluated. Using the radiocarbon isotopic signatures (Δ14C) of the seagrass Zostera marina and DIC, we show quantitatively that Z. marina takes up and assimilates atmospheric modern CO2 in a shallow coastal ecosystem. The Δ14C values of the seagrass (−36 to −8‰) were significantly higher than those of aquatic DIC (−45 to −18‰), indicating that the seagrass uses a 14C-rich carbon source (atmospheric CO2, +17‰). A carbon-source mixing model indicated that the seagrass assimilated ~ 46% (mean: 22%) of its inorganic carbon as atmospheric CO2. CO2 exchange between the air and the seagrass may be enhanced by the presence of a very thin water film over the air-exposed leaves during low tide. Our radiocarbon isotope analysis, showing assimilation of atmospheric modern CO2 as an inorganic carbon source, offers better understanding of the role of seagrass meadows in coastal carbon dynamics.
Seasonal hydrology drives rapid shifts in the flux and composition of dissolved and particulate organic carbon and mercury in the Fraser River, Canada
Authors: Voss B. M. , Peucker-Ehrenbrink B. , Eglinton T. I. , Spencer R. G. M. , Bulygina E. , Galy V. , Lamborg C. H. , Ganguli P. M. , Montluçon D. B. , Marsh S. , Gillies S. L. , Fanslau J. , Epp A. , Luymes R.
Published: May 2015

Abstract. Rapid changes in the volume and sources of discharge during the spring freshet lead to pronounced variations in biogeochemical properties in snowmelt-dominated river basins. We used daily sampling during the onset of the freshet in the Fraser River (southwestern Canada) in 2013 to identify rapid changes in the flux and composition of dissolved material, with a focus on dissolved organic matter (DOM) and mercury (Hg) dynamics. Previous time series sampling (at twice monthly frequency) of dissolved inorganic species in the Fraser River has revealed smooth seasonal transitions in concentrations of major elements and tracers of water and dissolved load sources between freshet and base flow periods. In contrast, daily sampling reveals a significant increase in dissolved organic carbon (DOC) concentration (200 to 550 μmol L−1) occurring over a matter of days, accompanied by a shift in DOM optical properties, indicating a transition towards higher molecular weight, more aromatic DOM composition. Comparable changes in DOM composition, but not concentration, occur at other times of year, underscoring the role of seasonal climatology in DOM cycling. Concentrations of total and dissolved Hg also varied during the spring freshet period, although dissolved Hg dynamics appear to be driven by factors beyond DOM as characterized here. The time series records of DOC and particulate organic carbon (POC) concentrations indicate that the Fraser River exports 0.25–0.35% of its annual basin net primary productivity.
Distribution of intermediate water masses in the subtropical northeast Atlantic
Authors: Bashmachnikov I. , Nascimento Â. , Neves F. , Menezes T.
Published: May 2015

Abstract. This work presents the quantitative study of climatological distributions of mid-depth Source Water Types in the NE Atlantic by the Optimum Multiparameter analysis (OMP), merging a~number of regional results from particular synoptic sections. The cores of the Mediterranean Water (MW), the modified Antarctic Intermediate Water (mAAIW) and the Subarctic Intermediate Water (SAIW) are detected and spatial variations of their depth/density are obtained: as expected, spreading of the source water types is predominantly isopycnic and follows the major mid-depth circulation patterns. In some areas the turbulent transport should also be considered. The MW in the Atlantic spreads as 3 cores of different density: the upper MW core (northwest of the first transition line between 28° W, 35° N and 14° W, 44° N) is found in the neutral density range of 27.65–27.70 kg m−3 and depths of 900–1000 m; the main MW core (northwest of the second transition line between 35° W, 28° N and 10° W, 37° N) has neutral density around 27.75 kg m−3 and is found at 1000–1100 m; the lower MW core (southeast of the second transition) has neutral density around 27.80 kg m−3 and is found at 1250–1350 m. The upper MW core has comparatively low MW contents (below 30%) and is speculated to be transported by the mean flow from the northern Iberian Peninsula and the Bay of Biscay to the northern Azores. The main MW core contains the most of the MW. It primarily originates from the MUC between Cape St. Vincent and Estremadura Promontory, where the strongest local decrease of the topographic β-effect is detected and is transported west by a flow at around 39° N. The lower MW core originates in the Gulf of Cadiz and is translated southwestwards by dominating flows. The SAIW (the core between 27.70 and 27.75 kg m−3) is found to spread south along both slopes of the MAR. The SAIW east of the MAR mixes with the upper and the main MW cores and re-circulates in a cyclonic gyre at 15–25° W and 34–39° N as far south as the Azores Current. The northernmost spreading limit of the mAAIW (the core between 27.60 and 27.65 kg m−3) is at 25–29° N, but its influence reaches 32° N east and west of the Canary Islands. Its maximum concentration is found south of the Canaries, from where the mAAIW is transported westwards, parallel to the westward transport of the deep fraction of the MW.
On the modulation of the periodicity of the Faroe Bank Channel overflow instabilities
Authors: Darelius E. , Fer I. , Rasmussen T. , Guo C. , Larsen K. M. H.
Published: May 2015

Abstract. The Faroe Bank Channel (FBC) is one of the major pathways where dense, cold water formed in the Nordic Seas flows southward towards the north Atlantic. The plume region downstream of the FBC sill is characterized by high mesoscale variability, quasi-regular oscillations and intense mixing. Here, one year-long time series of velocity and temperature from eight moorings deployed in May 2012 in the plume region is analyzed to describe variability in the strength and period of the oscillations. The eddy kinetic energy (EKE) associated with the oscillations is modulated with a factor of ten during the year and the dominant period of the oscillations changes between three to four and six days, where the shorter period oscillations are more energetic. The dense water is observed on a wider portion of the slope (both deeper and shallower) during periods with energetic, short period oscillations. The observations are complemented by results from a regional, high resolution model that shows a similar variability in EKE and a gradual change in oscillation period between three and four days. The observed variability in oscillation period is directly linked to changes in the volume transport across the sill: the oscillation period decreases with about six days Sv−1 both in the observations and in the model. This is in agreement with results from linear instability analysis which suggests that the period and growth rate decrease for decreased plume thickness. The changes in oscillation period can partly be explained by variability in the upper layer, background flow and advection of the oscillations past the stationary moorings, but the changes in the fraction of the EKE that is derived from the cross isobath motion suggests that the intrinsic period of the instability is modulated. It is further shown that about 50% of the transport variability across the sill is explained by changes in the local barotropic forcing, which is obtained from satellite altimetry.
Does Jatropha curcas L. show resistance to drought in the Sahelian zone of West Africa? A case study from Burkina Faso
Authors: Bayen P. , Sop T. K. , Lykke A. M. , Thiombiano A.
Published: May 2015

Abstract. Land degradation is an environmental problem which weakens agro-sylvo-pastoral productivity in sub-Saharan Africa. The most common manifestation of land degradation is the appearance of denuded land. We carried out an experiment to test the effect of three soil and water conservation techniques on survival and growth of Jatropha curcas seedlings transplanted onto two completely denuded lands in the Sahelian and Sudanian zones of Burkina Faso. We implemented an experimental design with three replicates per restoration technique. A total of 174 seedlings were planted in each study site. The results showed that the soil water content varied according to the restoration technique used (df = 2; F = 53.21; p < 0.00) as well as according to study site (df = 1; F = 74.48; p < 0.00). Soil water content was significantly lower in the Sahel than in the Sudanian zone. Seedling survival rate varied significantly according to technique used (df = 2; F = 8.91; p = 0.000) and study site (df = 1; F = 9.74; p = 0.003). Survival rate, diameter and seedling height were highest at the Sudanian site. At the Sahelian site, all seedlings died 2 years after establishment. These results suggest that J. curcas is unsuited to denuded land in the Sahelian zone. Most of the plants died in the Sahel between April and May, which is the peak of the dry season; this may be an indication that J. curcas may not be as drought-resistant as suggested by the prolific literature which has reported on diverse claims surrounding this plant.
Stress field sensitivity analysis in a sedimentary sequence of the Alpine foreland, northern Switzerland
Authors: Hergert T. , Heidbach O. , Reiter K. , Giger S. B. , Marschall P.
Published: May 2015

Abstract. The stress field at depth is a relevant parameter for the design of subsurface constructions and reservoir management. Yet the distortion of the regional stress field due to local-scale features such as sedimentary and tectonic structures or topography is often poorly constrained. We conduct a stress sensitivity analysis using 3-D numerical geomechanical modelling with an elasto-plastic material law to explore the impact of such site-specific features on the stress field in a sedimentary sequence of the Swiss Alpine foreland. The model's dimensions are 14 × 14 × 3 km3 and it contains 10 units with different mechanical properties, intersected by two regional fault zones. An initial stress state is established involving a semi-empirical relationship between the ratio of horizontal to vertical stress and the overconsolidation ratio of argillaceous sediments. The model results indicate that local topography can affect the stress field significantly to depths greater than the relief contrasts at the surface, especially in conjunction with horizontal tectonic loading. The complexity and frictional properties of faults are also relevant. The greatest variability of the stress field arises across the different sedimentary units. Stress magnitudes and stress anisotropy are much larger in stiffer formations such as massive limestones than in softer argillaceous formations. The stiffer formations essentially carry the load of the far-field forces and are therefore more sensitive to changes of the boundary conditions. This general characteristic of stress distribution in the stiff and soft formations is broadly maintained also with progressive loading towards the plastic limit. The stress field in argillaceous sediments within a stack of formations with strongly contrasting mechanical properties like in the Alpine foreland appears to be relatively insensitive to changes in the tectonic boundary conditions and is largely controlled by the maximum stiffness contrast with respect to the load-bearing formations.
The Marrakesh Treaty For Visually Impaired Persons: Why A Treaty Was Preferable To Soft Law
Authors: Kaminski Margot E. , Yanisky-Ravid Shlomit
Published: May 2015

This paper addresses the debates leading up to the recently adopted international treaty on copyright exceptions for the visually impaired, the Marrakesh International Treaty to Facilitate Access to Published Works for Persons Who Are Blind, Visually Impaired, or Otherwise Print Disabled. This treaty was successfully adopted by the World Intellectual Property Organization (WIPO) in June 2013. Leading up to the negotiation of this instrument, multiple UN member states pushed for the instrument to be negotiated as soft law instead of a treaty. We argue that making this instrument soft law would have precluded its success. WIPO thus correctly chose to make this international instrument a treaty rather than a joint recommendation. This paper explains the international need for this instrument, to solve a global “book famine” and protect the access rights of visually impaired people. It then outlines the debate that occurred leading up to adoption over whether the instrument should be hard law or soft law. This debate illuminates that discussions of hard versus soft law need to be situated in context. We explore both related human rights law and other international copyright law to explain how they altered the hard law-soft law calculation in this case.The concluded treaty reflects WIPO’s recognition of related copyright law that had been established in other forums. By creating a binding instrument, WIPO has encouraged developing countries to implement the new treaty, towards the goal of assisting those visually impaired persons most in need of an international solution.
An efficient method for modelling tourists’ length of stay
Authors: Santos Glauber Eduardo de Oliveira
Published: May 2015

Modelling tourists’ length of stay imposes relevant challenges to researchers. The log-linear ordinary least squares (OLS) regression is a simple but limited statistical technique due to its log-normal distributional assumption. Duration models allow more flexible distributional assumptions, but they create unnecessary statistical complexity. Considering these limitations, a third and most efficient alternative that joins statistical simplicity and distributional flexibility is examined in this article. Generalized linear models (GLMs) are used to explain tourists’ length of stay at each of 100 Brazilian destinations. The log-gamma distribution is shown generally to fit data better than the log-normal alternative, indicating that GLMs outperform the log-linear OLS without requiring the complexity of duration models.
Field Trip #2 Aljustrel and the Central Iberian Pyrite Belt
Authors: Silva José B. , Oliveira Vítor , Matos João , Leitão José C.
Published: May 2015

During the morning, after a short introductory explanation, a visit to the Moinho mine is scheduled, depending on the situation of the mining company at the time. An alternative observation of representative drill cores from both the Moinho and Feitais deposits will take place as well as a surface cross section in the Moinho mine area. During the afternoon an overall cross section on the Aljustrel Anticlinorium will show the main geological features of this mining area.

A cross section at level 200 showing the major geological setting of the deposit will be seen (Figure 2.1). This will require a 500m walk; for all other courses a transport will be available. The massive sulfide mineralization will be observed in a more detail in the stopes of level 304 (Figure 2.2).

Stop 1 The reversed limb of the Southwest Anticline at level 200.

The Paraíso Siliceous Formation includes black shales, violet and green tuffitic shales, cherts and jaspers. The first folding phase axial plane schistose cleavage and the second phase axial plane crenulation cleavage and its intersection lineation are clear, as well as second phase folds.

Stop 2 Core of the Southwest Anticline at level 200.

Most of the different lithologies of the Felsitic Facies — Mine Tuff suite are observable, including: volcanic breccias with blocks up to 1m size, different tuff lithologies, ignimbritic (?) rocks and black shales interbedded.

Stop 3 Core of the S. João Syncline at level 200.

The mineralized level is repeated by folding.
FIELD TRIP #3 Eastern Iberian Pyrite Belt (Spain)
Authors: Almodóvar Gabriel R. , Pascual Emilio , Sáez Reinaldo , Toscano Manuel
Published: May 2015

The Spanish part of the Iberian Pyrite Belt embraces a number of supergiant massive sulfide deposits, as well as a great number of small-sized ones, altogether showing a wide variety of contrasted geological and metallogenic features. This makes the zone important, not only for its present-day economic status, but also from a historic point of view. On the other hand, some key geological features to understanding the geology and ore genesis in the IPB are better represented in its eastern part. Therefore, this field trip will be devoted to give an overview of the geological features of the IPB, together with the visit of three world-class massive sulfide deposits: Tharsis, Riotinto and Aznalcóllar (Figure 3.1). Also included is a historical approach to the importance of mining in the region through time, including a visit to the Riotinto Mining Museum.

The first day will be devoted to recognizing some geological features of the Puebla de Guzmán anticlinorium relevant to understanding the geological context where massive sulfides were deposited. A guided visit to the Filón Norte mine (Tharsis district), emphasizing the geologic and metallogenetic aspects, will enable debate over some peculiar features of the IPB massive sulfide deposits.

The second day will be spent around the Riotinto district, which is world famous as representative of the Iberian Pyrite Belt. At present mining in Riotinto is on gossan (Au-Ag) and stockwork (Cu) mineralizations, it is difficult to have a detailed run into places where massive sulfides are exposed. Nevertheless, it is worthwhile to
How are healthcare institutions using Facebook to interact with online communities? Results from a case study in Central Pennsylvania
Authors: R. George Daniel , Kime Lauren , D. Riley Timothy
Published: May 2015

Social media tools and applications are increasingly being integrated into modern medicine. However, little is known about how healthcare institutions are interacting online with their populations. In this case study, we identified a convenience sample of 11 institutions in Central Pennsylvania with Facebook Pages and evaluated their interactions with online communities. From May-June 2013, we noted type of healthcare institution (e.g. hospital, family practice); number of overall “likes” accrued by the healthcare facility; number of overall posts and “likes”, “comments”, and “content shares” associated with those posts; as well as number of location check-ins by “followers”. We thematically categorized each institutional post. Average number of Facebook Page “likes” was 2,261, and average number of overall posts was 28.9, or about one post every three days. On average, each post generated 16 “likes”, 1 comment, and 2.4 shares. Average number of location “check-ins” by visiting patients was 6,348. Most commonly published content across all Pages was advertisements (89%) and institutional news (89%). Patient populations in Central Pennsylvania are seeking out healthcare institutions on Facebook, although most communication appears unidirectional and involves institutional advertising and promotion. There are opportunities for institutions to focus on health promotion and undertake “social” preventive health strategies using social media.
Factors Affecting Response to Infertility Treatment: Case of Iran
Authors: Peyromusavi Fatemeh , Barouni Mohsen , Naderi Tayebeh , Shahravan Arash
Published: May 2015

INTRODUCTION: Infertility affects both women and men in all the countries. Infertility often has profound long-term or short-term impacts on the people involved and puts them at risk of familial and social pressures. According to WHO estimates, between 8% and 12% of all the couples worldwide experience some form of infertility during their reproductive life, i.e. 50‒80 million people are affected. The aim of this study was to evaluate the response to infertility treatment by taking into account factors such as age, hirsutism, menstruation and galactose among women in Kerman.

METHODOLOGY: Of a total of 300 patient files evaluated 220 cases were flawless, of which the study factors were recorded. These data were estimated by Logit model. The dependent variable was the response to treatment (0 and 1) and the independent variables included age of men and women, hirsutism, menstruation, galactose, duration of the period no preventive measures were used and body mass index. After entering the data, model output was analyzed by using the STATA software.

RESULTS: The results showed that of all the model variables, female age (prob=0.0065), menstruation (prob=0.04), hirsutism (prob=0.02), marriage age (in months) (prob=0.02) and BMI were significant and other variables were not significant. McFadden analysis for goodness of fit was 0.92.

CONCLUSION: The study results showed that women should pay more attention to variables such as BMI, menstruation quality (regular and irregular) and aging because clinical disregard of any of the above can have a significant impact on the individual’s fertility.
Kansen en barrières voor implementatie van de landelijke Handreiking Gezonde Gemeente in de GGD-organisatie
Authors: Kuunders Theo J.M. , van de Goor Ien A.M. , Paulussen Theo G.W.M. , van Bon-Martens Marja J.H. , van Oers Hans A.M.
Published: May 2015

De Handreiking Gezonde Gemeente, een landelijk instrument voor verbetering van integraal gemeentelijk gezondheidsbeleid, wordt volgens de Gezondheidsinspectie onvoldoende gebruikt. Deze studie onderzoekt mogelijkheden voor verbeterde implementatie van de handreiking in de GGD-organisatie.

Diverse GGD-disciplines, gemeenteambtenaren en externe respondenten zijn geïnterviewd over ervaringen en opvattingen aangaande de handreiking.

Naast een positieve inhoudelijke waardering is er een sterke roep om concrete vertaling naar het ‘hoe’ van het gebruik. De directe voordelen van het instrument voor betrokken professionals en managers binnen en buiten de GGD-en zijn onvoldoende geëxploreerd.

Als GGD-en het als taak zien om het gebruik van de handreiking door professionals, gemeenten en partners te stimuleren, dan zullen zij eerst de voordelen ervan moeten expliciteren. Bereidheid bij GGD-managers om professionals te sturen en faciliteren op het gebruik van instrumenten lijkt hiervoor een belangrijke randvoorwaarde.
Composiciones metafóricas: Richardson, Sullivan y Wright
Authors: Díez Barreñada Rafael
Published: May 2015

Aunque brevemente, y aunque ya ha sido señalada anteriormente, vamos a insistir en la relación existente entre tres maestros de la arquitectura americana, ya que ciertos aspectos de su obra nos ayudarán a entender una conexión entre el pensamiento arquitectónico y lo que llamamos artesanía, pues introducen en sus edificios la reflexión sobre la manipulación de la materia como metáfora formal capaz de configurar visualmente un edificio.

We insist on the relationship between three Masters of American architecture. Certain aspects of his work help us to understand the importance in the architectural thought of materiality as a formal metaphor capable of introducing visual order to a building.

The relationship between the latter two is well known. Wright, in his writings, described Sullivan as a master, from who inherited the use of the word organic. But, to a large extent, organic refers to a formal quality that made Sullivan appreciated the work of Richardson above his other contemporaries, and which the author himself would call, in his few writings, as living architecture: one that without being monotonous stands out for its tranquility and simplicity. Sullivan perceives that the main characteristic of the buildings of Richardson is their unity. Is to this complex unity, as that of a living being, that the other two refer to with the term organic.

Richardson was very subtle formally. At the Marshall Field building, classical tripartition (beginning, development and end) is resolved with a very complex modulation, which creates subtle visual tensions that link parts among themselves, not only by position but by also by affinity. The building, thanks to his series of horizontal bands, is three and four, and their different groupings and intersections, which creates vertical stresses that unify it.

What in Richardson is accomplished by the tension between elements, at Sullivan is reduced to the continuity of all elements, which are nothing more than one, tour around by a plant line that twists on itself. It is the metaphor as an visual image.

Wright picks up the formal model of the libraries of Richardson, and reformulates the principle that governs them. A building, to have unity, rather than the pure physical continuity, needs to establish a law that links different parts. That is the beginning of his famous “breaking” the box, the classical building as a single volume. He establishes a system of verticals and horizontals, whose unity is not secured by the establishment of precise limits but because they criss-cross and their complementary nature.

If those lines, in Richardson, are strains of a composition sculpted on a solid, which prompted Sullivan to identify unity with the own solid and its limits, at Wright these lines become volumetric elements governed by a compositional law, not abstract but metaphorical. The organic is no longer applied motiv, ornament, but constructed metaphor.
Centre Cívic El Roure i Biblioteca La Ginesta
Authors: Calderón Pilar , Folch Marc , Sarsanedas Pol
Published: May 2015

El Centre Cívic El Roure i Biblioteca La Ginesta és un equipament cultural mixt que engloba un centre cívic amb teatre polivalent i una biblioteca municipal fruit d’un procés de treball comú entre tècnics,  administració i ciutadans. Plenament integrat al seu entorn, el centre és un catalitzador social i cultural que revalora un espai natural amb la recuperació paisatgística de la Riera Fonda de Begues i d’un exemplar de roure martinenc que dona nom al centre.
Drought: A Gamechanger In Texas?
Authors: Shaw Kristi
Published: May 2015

Large sections of Texas experienced exceptional or extreme drought from 2010 through early 2015, straining water supplies for all uses. Further, climate change complicates projecting future water supply and demand. Vigorous drought mitigation and resiliency planning is an essential element of the state's sustainable water resources management.
Biological Pretreatment Extends Membrane Service Life
Authors: Weng Shengtao , Miller Scott , Suthaker Supramaniam
Published: May 2015

During the past 12 years, six small water treatment systems in Western Canada have used biological filtration as a pretreatment process for reverse osmosis membranes.
A new family of StART domain proteins at membrane contact sites has a role in ER-PM sterol transport
Authors: Gatta Alberto T , Wong Louise H , Sere Yves Y , Calderón-Noreña Diana M , Cockcroft Shamshad , Menon Anant K , Levine Tim P
Published: May 2015

Sterol traffic between the endoplasmic reticulum (ER) and plasma membrane (PM) is a fundamental cellular process that occurs by a poorly understood non-vesicular mechanism. We identified a novel, evolutionarily diverse family of ER membrane proteins with StART-like lipid transfer domains and studied them in yeast. StART-like domains from Ysp2p and its paralog Lam4p specifically bind sterols, and Ysp2p, Lam4p and their homologs Ysp1p and Sip3p target punctate ER-PM contact sites distinct from those occupied by known ER-PM tethers. The activity of Ysp2p, reflected in amphotericin-sensitivity assays, requires its second StART-like domain to be positioned so that it can reach across ER-PM contacts. Absence of Ysp2p, Ysp1p or Sip3p reduces the rate at which exogenously supplied sterols traffic from the PM to the ER. Our data suggest that these StART-like proteins act in trans to mediate a step in sterol exchange between the PM and ER.
Structure of a type IV pilus machinery in the open and closed state
Authors: Gold Vicki AM , Salzer Ralf , Averhoff Beate , Kühlbrandt Werner
Published: May 2015

Proteins of the secretin family form large macromolecular complexes, which assemble in the outer membrane of Gram-negative bacteria. Secretins are major components of type II and III secretion systems and are linked to extrusion of type IV pili (T4P) and to DNA uptake. By electron cryo-tomography of whole Thermus thermophilus cells, we determined the in situ structure of a T4P molecular machine in the open and the closed state. Comparison reveals a major conformational change whereby the N-terminal domains of the central secretin PilQ shift by ∼30 Å, and two periplasmic gates open to make way for pilus extrusion. Furthermore, we determine the structure of the assembled pilus.
Storm‐enhanced plasma density and polar tongue of ionization development during the 15 May 2005 superstorm
Authors: Horvath Ildiko , Lovell Brian C.
Published: May 2015

We investigate the ionosphere's global response to the 15 May 2005 superstorm in terms of storm evolution and ionospheric electrodynamics. Our aim is to study the global distribution of plasma and the resultant large‐scale ionospheric features including the equatorial ionization anomaly (EIA), storm‐enhanced density (SED), and polar tongue of ionization (TOI). We have combined multi‐instrument ionospheric data, solar and terrestrial magnetic data, and polar convection maps. Results reveal the prompt penetration of the interplanetary electric field to the polar region and then to the equator with a dusk‐to‐dawn polarity during the initial phase and with a dawn‐to‐dusk polarity during the main phase. This drove during the initial phase a weak eastward equatorial electrojet (EEJ) in the American sector at nighttime and a weak westward EEJ in the Indian‐Australian sector at daytime. During the main phase, these EEJs intensified and changed polarities. SED and polar TOI development was observed prior to and during the initial phase at evening‐premidnight hours over North America and during the main phase in the south at afternoon‐evening hours in the Australian sector. During the main phase and early in the recovery phase, the EIA‐SED structure was well formed in the Asian longitude sector. Then, polar TOI development was absent in the north because of the long distance from the magnetic pole but was supported in the south because of the closeness of daytime cusp and magnetic pole. Thus, the EIA‐SED‐TOI structure developed twice but each time in a different longitude sector and with different characteristics.
Ring of impact from the mega‐urbanization of Beijing between 2000 and 2009
Authors: Jacobson Mark Z. , Nghiem Son V. , Sorichetta Alessandro , Whitney Natasha
Published: May 2015

The transient climate, soil, and air quality impacts of the rapid urbanization of Beijing between 2000 and 2009 are investigated with three‐dimensional computer model simulations. The simulations integrate a new satellite data set for urban extent and a geolocated crowd‐sourced data set for road surface area and consider differences only in urban land cover and its physical properties. The simulations account for changes in meteorologically driven natural emissions but do not include changes in anthropogenic emissions resulting from urbanization and road network variations. The astounding urbanization, which quadrupled Beijing urban extent between 2000 and 2009 in terms of physical infrastructure change, created a ring of impact that decreased surface albedo, increased ground and near‐surface air temperatures, increased vertical turbulent kinetic energy, and decreased the near‐surface relative humidity and wind speed. The meteorological changes alone decreased near‐surface particulate matter, nitrogen oxides (NOx), and many other chemicals due to vertical dilution but increased near‐surface ozone due to the higher temperature and lower NO. Vertical dilution and wind stagnation increased elevated pollution layers and column aerosol extinction. In sum, the ring of impact around Beijing may have increased urban heating, dried soil, mixed pollutants vertically, aggravated air stagnation, and increased near‐surface oxidant pollution even before accounting for changes in anthropogenic emissions.
Spectral properties of Titan's impact craters imply chemical weathering of its surface
Authors: Neish C. D. , Barnes J. W. , Sotin C. , MacKenzie S. , Soderblom J. M. , Le Mouélic S. , Kirk R. L. , Stiles B. W. , Malaska M. J. , Le Gall A. , Brown R. H. , Baines K. H. , Buratti B. , Clark R. N. , Nicholson P. D.
Published: May 2015

We examined the spectral properties of a selection of Titan's impact craters that represent a range of degradation states. The most degraded craters have rims and ejecta blankets with spectral characteristics that suggest that they are more enriched in water ice than the rims and ejecta blankets of the freshest craters on Titan. The progression is consistent with the chemical weathering of Titan's surface. We propose an evolutionary sequence such that Titan's craters expose an intimate mixture of water ice and organic materials, and chemical weathering by methane rainfall removes the soluble organic materials, leaving the insoluble organics and water ice behind. These observations support the idea that fluvial processes are active in Titan's equatorial regions.
From connected pathway flow to ganglion dynamics
Authors: Rücker M. , Berg S. , Armstrong R. T. , Georgiadis A. , Ott H. , Schwing A. , Neiteler R. , Brussee N. , Makurat A. , Leu L. , Wolf M. , Khan F. , Enzmann F. , Kersten M.
Published: May 2015

During imbibition, initially connected oil is displaced until it is trapped as immobile clusters. While initial and final states have been well described before, here we image the dynamic transient process in a sandstone rock using fast synchrotron‐based X‐ray computed microtomography. Wetting film swelling and subsequent snap off, at unusually high saturation, decreases nonwetting phase connectivity, which leads to nonwetting phase fragmentation into mobile ganglia, i.e., ganglion dynamics regime. We find that in addition to pressure‐driven connected pathway flow, mass transfer in the oil phase also occurs by a sequence of correlated breakup and coalescence processes. For example, meniscus oscillations caused by snap‐off events trigger coalescence of adjacent clusters. The ganglion dynamics occurs at the length scale of oil clusters and thus represents an intermediate flow regime between pore and Darcy scale that is so far dismissed in most upscaling attempts.
Earthward and tailward flows in the plasma sheet
Authors: Zhang L. Q. , Wang J. Y. , Baumjohann W. , Rème H. , Dunlop M. W.
Published: May 2015

Utilizing C3/Cluster satellite observations from the year of 2001 to 2006, we investigated the earthward flow (EF) and tailward flow (TF) at Bz > 0 in the plasma sheet. We found that the EF and the TF have similar spatial distributions. Both characteristics are independent of the distance beyond 14 RE. Both flows are deflected while closer to the Earth. Statistical results further showed that the EF/TF occur in the central plasma sheet as well as the plasma sheet boundary layer and can be observed during quiet times and periods of geomagnetic activity. A typical event reveals that the EF and the TF have different plasma population. A transition region (TR) can be formed at the interface between the EF and TF. Very significant duskward components appeared in bulk velocities for both populations. It appears that the vortical‐like structure can be formed near the TR. The magnetic field within the TR is twisted and strongly fluctuates. No clear magnetic flux pileups are observed inside the TR.
Solar zenith angle‐dependent asymmetries in Venusian bow shock location revealed by Venus Express
Authors: Chai Lihui , Wan Weixing , Fraenz Markus , Zhang Tielong , Dubinin Eduard , Wei Yong , Li Yi , Rong Zhaojin , Zhong Jun , Han Xiuhong , Futaana Yoshifumi
Published: May 2015

It has been long known that the Venusian bow shock (BS) location is asymmetric from the observations of the long‐lived Pioneer Venus Orbiter mission. The Venus Express (VEX) mission crossed BS near perpendicularly not only in the terminator region but also in the near‐subsolar and tail regions. Taking the advantage of VEX orbit geometry, we examined a large data set of BS crossings observed during the long‐lasting solar minimum between solar cycles 23 and 24 and found that the Venusian BS asymmetries exhibit dependence of solar zenith angle. In the terminator and tail regions, both the magnetic pole‐equator and north‐south asymmetries are observed in Venusian BS location, which is similar to the Pioneer Venus Orbiter (PVO) observation near terminator. However, in the near‐subsolar region, only the magnetic north‐south is observed; i.e., the BS shape is indented inward over magnetic south pole and bulged outward over magnetic north pole. The absence of the magnetic pole‐equator asymmetry in the near‐subsolar region suggests that the magnetic pole‐equator asymmetry is mainly caused by the asymmetric wave propagation rather than the ion pickup process. The evident magnetic north‐south asymmetry in solar minimum, which is not observed by PVO, suggests that even during the low long‐lasting solar minimum, the ion pickup process is very important in Venusian space environment.
Mechanical instability induced by water weakening in laboratory fluid injection tests
Authors: David C. , Dautriat J. , Sarout J. , Delle Piane C. , Menéndez B. , Macault R. , Bertauld D.
Published: May 2015

To assess water‐weakening effects in reservoir rocks, previous experimental studies have focused on changes in the failure envelopes derived from mechanical tests conducted on rocks fully saturated either with water or with inert fluids. So far, little attention has been paid to the mechanical behavior during fluid injection under conditions similar to enhanced oil recovery operations. We studied the effect of fluid injection on the mechanical behavior of the weakly consolidated Sherwood sandstone in laboratory experiments. Our specimens were instrumented with 16 ultrasonic P wave transducers for both passive and active acoustic monitoring during loading and fluid injection to record the acoustic signature of fluid migration in the pore space and the development of damage. Calibration triaxial tests were conducted on three samples saturated with air, water, or oil. In a second series of experiments, water and inert oil were injected into samples critically loaded up to 80% or 70% of the dry or oil‐saturated compressive strength, respectively, to assess the impact of fluid migration on mechanical strength and elastic properties. The fluids were injected with a low back pressure to minimize effective stress variations during injection. Our observations show that creep takes place with a much higher strain rate for water injection compared to oil injection. The most remarkable difference is that water injection in both dry and oil‐saturated samples triggers mechanical instability (macroscopic failure) within half an hour whereas oil injection does not after several hours. The analysis of X‐ray computed tomography images of postmortem samples revealed that the mechanical instability was probably linked to loss of cohesion in the water‐invaded region.
Modeling flood dynamics along the superelevated channel belt of the Yellow River over the last 3000 years
Authors: Chen Yunzhen , Overeem Irina , Kettner Albert J. , Gao Shu , Syvitski James P. M.
Published: May 2015

The Yellow River, China, experienced >1000 levee breaches during the last 3000 years. A reduced‐complexity model is developed in this study to explore the effects of climate change and human activity on flood levels, levee breaches, and river avulsions. The model integrates yearly morphological change along a channel belt with daily river fluxes and hourly evolution of levee breaches. Model sensitivity analysis reveals that under natural conditions, superelevation of the channel belt dominates flood frequency. When there is significant human‐accelerated basin erosion and breach repair, the dominant factors shift to a combination of mean annual precipitation, superelevation, critical shear stress of weak channel banks, and the time interval between breach initiation and its repair. The effect of precipitation on flood frequency is amplified by land use changes in the hinterland, particularly in the erodible Loess Plateau. Uncertainty analysis estimates the most likely values of the dominant factors for six historical periods between 850 B.C. and A.D. 1839, which are used to quantitatively reconstruct flood dynamics. During 850 B.C. to A.D. 1839, when the sediment load increased fourfold, the breach recurrence interval was shortened from more than 500 years to less than 6 years, and the breach outflow rate increased ~27 times. River management practices during A.D. 1579 to A.D. 1839 focused on levees and triggered a severe positive feedback of increased levee heights and flood hazard exacerbation. Raising the levee heights proved to be ineffective for sustainable flood management.