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Finding an explicit solution to the widely used Green–Ampt (G–A) one‐dimensional infiltration model has been subject of efforts for more than half a century. We derived an explicit semiempirical approach that combines accuracy with simplicity, a concept that has been generally neglected in previous studies. The equation is F=Kst(0.70635+0.324151+9.43456(S2Ks2t))$F\; = {K_s}\;t\;({0.70635 + 0.32415\sqrt {1 + 9.43456({\frac{{{S^2}}}{{{K_s}^2t}}})} })$, with F (L), Ks (L/T), S (L/T0.5) and t (T) being cumulative infiltration, saturated hydraulic conductivity, sorptivity, and time, respectively. Relative errors (ɛ) by the application of this equation generally do not exceed ±0.3% in most applied infiltration problems faced by water resources engineering today. We show both numerically and mathematically that │ɛ│> 0.3% could only occur if Kst/F > 0.904, a criterion that could apply to sand and loamy sand soils (i.e., coarse texture) and if they experience infiltration rates for over 6 h and 19 h, respectively. Hence, we also derived a simple linear adjustment in the model as Fadj ≅ 0.9796 F + 0.335 S2/Ks to address these longer infiltration rates, and to assure that ɛ remains within the expected ±0.3% range of uncertainty. A linearized regression technique was also developed to accurately estimate S and Ks when the G–A model is used. We numerically demonstrated that our fitting method could be used even when the G–A approach is less valid (diffusive soils), provided that the actual value of the capillary length (λ) is initially known. An added benefit of our approach is that by setting λ equal to 1/3 and 2/3, it can significantly limit the range of initializing, unknown, a priori values of S and Ks, as these two parameters are estimated through the inverse solution of implicit infiltration models. Due to the model's simplicity and accuracy, our solution should find application among hydrologists, natural resource scientists, and engineers who wish to easily derive accurate estimations from the G–A infiltration approach and/or estimate sorptivity and hydraulic conductivity without encountering divergence problems. Core Ideas: A new explicit form of the one‐dimensional Green–Ampt infiltration model was developed.This model combined simplicity, accuracy, and computational efficiency.A new linearized regression solution was derived to estimate sorptivity and hydraulic conductivity.This linearized fitting method can eliminate the risk of convergence associated with other numerical approaches. [ABSTRACT FROM AUTHOR]

The need to develop and provide integrated observation systems to better understand and manage global and regional environmental change is one of the major challenges facing Earth system science today. In 2008, the German Helmholtz Association took up this challenge and launched the German research infrastructure TERrestrial ENvironmental Observatories (TERENO). The aim of TERENO is the establishment and maintenance of a network of observatories as a basis for an interdisciplinary and long‐term research program to investigate the effects of global environmental change on terrestrial ecosystems and their socio‐economic consequences. State‐of‐the‐art methods from the field of environmental monitoring, geophysics, remote sensing, and modeling are used to record and analyze states and fluxes in different environmental disciplines from groundwater through the vadose zone, surface water, and biosphere, up to the lower atmosphere. Over the past 15 years we have collectively gained experience in operating a long‐term observing network, thereby overcoming unexpected operational and institutional challenges, exceeding expectations, and facilitating new research. Today, the TERENO network is a key pillar for environmental modeling and forecasting in Germany, an information hub for practitioners and policy stakeholders in agriculture, forestry, and water management at regional to national levels, a nucleus for international collaboration, academic training and scientific outreach, an important anchor for large‐scale experiments, and a trigger for methodological innovation and technological progress. This article describes TERENO's key services and functions, presents the main lessons learned from this 15‐year effort, and emphasizes the need to continue long‐term integrated environmental monitoring programmes in the future. Plain Language Summary: This paper discusses the importance of creating comprehensive environmental observation systems to better understand and address global and regional environmental changes. In 2008, a German research infrastructure named Terrestrial Environmental Observatories (TERENO) was established to build and maintain a network of observatories. The goal is to conduct interdisciplinary, long‐term research on the impacts of global environmental changes on terrestrial ecosystems and their socio‐economic effects. The TERENO network employs advanced methods from environmental monitoring, geophysics, remote sensing, and modeling to study various environmental aspects. Over the past 15 years, four observatories have been part of this network, contributing to valuable experience in overcoming challenges and exceeding expectations. Today, TERENO is a crucial component for environmental modeling and forecasting in Germany, serving as an information hub for practitioners and policymakers. It also fosters international collaboration, supports large‐scale experiments, and drives methodological and technological advancements. The article highlights key lessons learned from this 15‐year effort and emphasizes the importance of continuing such integrated environmental monitoring programs in the future. Key Points: Integrated observatories ensure a holistic Earth Systems perspective, offering data for current and future ecological challengesThe scientific and societal value of observatories is invaluable, but their design, construction and operation require considerable effortFor assured long‐term data collection, research infrastructure must have flexible design for adapting to changing research needs [ABSTRACT FROM AUTHOR]

Background: Lip investigations and characterizations in the literature are less prevalent than for skin, particularly on the topic of color diversity. However, as the consumer demand increases for a nude lip makeup result, that is, shades close to the bare lip color, the identification and modification of lip color is essential for the cosmetic industry. Objective: The objective was to highlight lip color diversity among three ethnicities (Caucasian, African and Hispanic), through the use of a spectral color measurement device especially adapted to the lip area, and to consider lip color ethnic specificities and overlaps. Materials and Methods: The inferior natural lip color was measured with a full‐face hyperspectral imaging system, SpectraFace (Newtone Technologies, Lyon, France), on 410 healthy women aged 19 to 68 (Caucasian French, Caucasian American, African American, and Hispanic American women). A hierarchical ascending classification, was deployed to determine clusters based on the lip colorimetric parameters along two strategies to identify the best statistical analysis to preserve the lip color diversity. Results: Lip color is a continuous color space, with great intra‐ethnic and inter‐ethnic diversity, especially for African American women in terms of chroma and lightness. Among the two strategies of data analysis, our two‐step statistical clustering analysis yielded 11 groups (i.e., 11 lip tones), revealing an accurate representation of the scope of diversity, but also of the overlaps. Conclusion: The 11 lip tones/colors could potentially serve as target shades for the development of a more diverse and inclusive range of lip cosmetics, such as nude lipsticks. [ABSTRACT FROM AUTHOR]

Copyright of African Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: The lips are of significant interest among the facial features for self‐perception and social interactions. Such perceptions could rely in part upon the contrast in color between the lips and the surrounding skin. In contrast to skin color, lip color ethnic diversity measurement provides a challenge and is less documented in the literature, most likely due primarily to challenges in measurement based upon the lip characteristics of size and contour. Accurate measurement and reproduction of lip color are essential to build strong cross‐sectional knowledge about lip color. Objective: This preliminary experiment of a large‐scale project on lip and skin color was designed to assess accuracy in lip color measurement and recommend instruments and protocols for good measurement practice. Methods: The study involved 19 healthy French Caucasian women. Their inferior and superior natural lip color was measured twice with three devices in order to extract the standard colorimetric parameters of lightness (L*), chroma (C*), and hue (h): the VISIA‐CR® (high‐resolution digital camera, Canfield Scientific Inc.); the spectrophotometer VS3200 (45°:0° spectrophotometer, MetaVue™ VS3200, X‐Rite Inc.); and the SpectraFace® (new hyperspectral imaging system, Newtone Technologies). The intercomparison and color distribution between the different instruments and the measurement repeatability of each one were assessed. Results: Our results showed a reliable and equivalent repeatability for the three tested instruments. Moreover, the three tools led to the same conclusion regarding lip color heterogeneity (lighter, redder, less yellow and more saturated inferior lip versus superior lip). Agreement between the SpectraFace® and the spectrophotometer measurements was higher, and the SpectraFace® allowed to identify three separated lip color typologies. Conclusion: In conclusion, the combination of imaging technology and hyperspectral measurement makes the SpectraFace® a useful tool to investigate lip color characterization and establish a large‐scale cross‐sectional knowledge study about lip color. [ABSTRACT FROM AUTHOR]

The increasing demand for plant‐derived bioenergy is projected to expand tree plantations with intensive silviculture and improved tree genetics. These silvicultural practices result in faster stand development and canopy closure, which may also influence the systems' water dynamics. Here, we studied the evapotranspiration (ET) of a young (5 years old) intensively managed loblolly pine (Pinus taeda) stand and investigated the components of ET to determine its contribution to overall water use. We also compared ET with plantations that received less intensive management to determine whether our stand used more water. We used the eddy covariance method to estimate ecosystem‐level total ET (ETEC), while plot‐level estimates of ET (ETP) were obtained via soil lysimeters, sap flow sensors, and throughfall collectors, enabling measurement of the components of ET. Soil evaporation (Es) was the largest component of ETP (36%) over the course of the study, while transpiration and canopy interception accounted for 27% and 22%, respectively. Es decreased with stand development, while transpiration and canopy interception increased. Leaf area index (LAI) and precipitation were the most significant factors controlling ET and its components. Compared to previous studies in different sites that have similar age but lower LAI, our stand had higher water use. This high water use in the early stages of stand development was primarily due to high Es before the canopy was fully developed. While there are potential sources of uncertainty when comparing ETEC and the component fluxes in ETP, results from the two methods were not significantly different. This study had the advantage of using multiple methods to understand and verify the component processes that contribute to ET. Therefore, we recommend that multiple measurement techniques be used in the long‐term observation of ET, and in particular for the evaluation of the impact that intensively managed forests have on water resources in the southeastern United States. [ABSTRACT FROM AUTHOR]

The development of several large‐, "continental"‐scale ecosystem research infrastructures over recent decades has provided a unique opportunity in the history of ecological science. The Global Ecosystem Research Infrastructure (GERI) is an integrated network of analogous, but independent, site‐based ecosystem research infrastructures (ERI) dedicated to better understand the function and change of indicator ecosystems across global biomes. Bringing together these ERIs, harmonizing their respective data and reducing uncertainties enables broader cross‐continental ecological research. It will also enhance the research community capabilities to address current and anticipate future global scale ecological challenges. Moreover, increasing the international capabilities of these ERIs goes beyond their original design intent, and is an unexpected added value of these large national investments. Here, we identify specific global grand challenge areas and research trends to advance the ecological frontiers across continents that can be addressed through the federation of these cross‐continental‐scale ERIs. Plain Language Summary: The development of several large‐, "continental"‐scale ecosystem research infrastructures over recent decades has provided a unique opportunity in the history of ecological science. By bringing together these research infrastructures and harmonizing their respective data will more broadly enable cross‐continental ecological research. It will also improve the capabilities of the research community to anticipate and address future global scale ecological challenges to the planet. Moreover, increasing the international capabilities of these research infrastructures goes beyond their original design intent, and is an unexpected added value of these large national investments. Here, we identify specific global grand challenge areas and research trends to advance the ecological frontiers across continents that can be addressed through the federation of these cross‐continental‐scale ecosystem research infrastructures. Key Points: For the first time in history, we are able to bring together continental‐scale Ecosystem Research Infrastructures globallyThis effort enables macrosystem ecologists to ask research questions from continent‐to‐continent in ways not available beforeThis effort provides baseline data to tackle current and future unknown ecological challenges that society will face [ABSTRACT FROM AUTHOR]

Microgels are soft colloids that show responsive behavior and are easy to functionalize for applications. They are considered key components for future smart colloidal material systems. However, so far microgel systems have almost exclusively been studied in classical responsive switching settings using external triggers, while internally organized, autonomous control mechanisms as found in supramolecular chemistry and DNA nanotechnology relying on fuel‐driven out‐of‐equilibrium concepts have not been implemented into microgel systems. Here, we introduce chemically fueled transient volume phase transitions (VPTs) for poly(methacrylic acid) (PMAA) microgels, where the collapsed hydrophobic state can be programmed using the fuel concentration in a cyclic reaction network. We discuss details of the system behavior as a function of pH and fuel amount, unravel kinetically trapped regions and showcase transient encapsulation and time‐programmed release as a first application. [ABSTRACT FROM AUTHOR]

There exists a critical need in biomedical molecular imaging and diagnostics for molecular sensors that report on slight changes to their local microenvironment with high spatial fidelity. Herein, a modular fluorescent probe, termed StyPy, is rationally designed which features i) an enormous and tunable Stokes shift based on twisted intramolecular charge transfer (TICT) processes with no overlap, a broad emission in the far‐red/near‐infrared (NIR) region of light and extraordinary quantum yields of fluorescence, ii) a modular applicability via facile para‐fluoro‐thiol reaction (PFTR), and iii) a polarity‐ and viscosity‐dependent emission. This renders StyPy as a particularly promising molecular sensor. Based on the thorough characterization on the molecular level, StyPy reports on the viscosity change in all‐DNA microspheres and indicates the hydrophilic and hydrophobic compartments of hybrid DNA‐based mesostructures consisting of latex beads embedded in DNA microspheres. Moreover, the enormous Stokes shift of StyPy enables one to detect multiple fluorophores, while using only a single laser line for excitation in DNA protocells. The authors anticipate that the presented results for multiplexing information are of direct importance for advanced imaging in complex soft matter and biological systems. [ABSTRACT FROM AUTHOR]

Nanostructures derived from amphiphilic DNA–polymer conjugates have emerged prominently due to their rich self‐assembly behavior; however, their synthesis is traditionally challenging. Here, we report a novel platform technology towards DNA–polymer nanostructures of various shapes by leveraging polymerization‐induced self‐assembly (PISA) for polymerization from single‐stranded DNA (ssDNA). A "grafting from" protocol for thermal RAFT polymerization from ssDNA under ambient conditions was developed and utilized for the synthesis of functional DNA–polymer conjugates and DNA–diblock conjugates derived from acrylates and acrylamides. Using this method, PISA was applied to manufacture isotropic and anisotropic DNA–polymer nanostructures by varying the chain length of the polymer block. The resulting nanostructures were further functionalized by hybridization with a dye‐labelled complementary ssDNA, thus establishing PISA as a powerful route towards intrinsically functional DNA–polymer nanostructures. [ABSTRACT FROM AUTHOR]

Wir stellen zweiwertige 3D‐DNA‐Origami‐Quader als monodisperse Kolloide vor und nutzen ihre Fähigkeit der molekularen Erkennung, um räumlich genau angeordnete Interaktionsmuster und eine definierte Anzahl supramolekularer Bindungsmotive zu erzeugen. Wir zeigen, dass Adamantan/β‐Cyclodextrin‐Wirt/Gast‐Einschlusskomplexe mit mäßiger Assoziationsstärke eine effiziente suprakolloidale Fibrillierung selbst bei hoher Verdünnung der 3D‐DNA‐Origami aufgrund kooperativer Multivalenz ermöglichen. Details der Assemblierung von Janus‐ und Nicht‐Janus‐3D‐DNA‐Origami zu suprakolloidalen Homo‐ und Heterofibrillen in Bezug auf Multivalenzeffekte, elektrostatische Abstoßung und Stöchiometrie werden aufgezeigt. Wir schlagen vor, dass die Vereinigung von 3D‐DNA‐Origami mit kolloidaler Selbstorganisation und supramolekularen Motiven neue Synergien an der Schnittstelle dieser Disziplinen bietet, um Multivalenzeffekte besser zu verstehen, strukturelle Komplexität zu fördern und die DNA‐Nanowissenschaften um Mechanismen zu erweitern, die Nicht‐DNA‐Assemblierung und Schaltung ergänzen. [ABSTRACT FROM AUTHOR]

We introduce divalent 3D DNA origami cuboids as truly monodisperse colloids and harness their ability for precision functionalization with defined patches and defined numbers of supramolecular binding motifs. We demonstrate that even adamantane/β‐cyclodextrin host/guest inclusion complexes of moderate association strength can induce efficient supracolloidal fibrillization at high dilution of the 3D DNA Origami as a result of cooperative multivalency. We show details on the assembly of Janus and non‐Janus 3D DNA origami into supracolloidal homo‐ and heterofibrils with respect to multivalency effects, electrostatic screening, and stoichiometry. We believe that the merger of 3D DNA origami with colloidal self‐assembly and supramolecular motifs provides new synergies at the interface of these disciplines to better understand multivalency effects, to promote structural complexity, and add non‐DNA assembling and switching mechanisms to DNA nanoscience. [ABSTRACT FROM AUTHOR]

Titin is a giant elastic protein expressed in the contractile units of striated muscle cells, including the sarcomeres of cardiomyocytes. The last decade has seen enormous progress in our understanding of how titin molecular elasticity is modulated in a dynamic manner to help cardiac sarcomeres adjust to the varying hemodynamic demands on the heart. Crucial events mediating the rapid modulation of cardiac titin stiffness are post‐translational modifications (PTMs) of titin. In this review, we first recollect what is known from earlier and recent work on the molecular mechanisms of titin extensibility and force generation. The main goal then is to provide a comprehensive overview of current insight into the relationship between titin PTMs and cardiomyocyte stiffness, notably the effect of oxidation and phosphorylation of titin spring segments on titin stiffness. A synopsis is given of which type of oxidative titin modification can cause which effect on titin stiffness. A large part of the review then covers the mechanically relevant phosphorylation sites in titin, their location along the elastic segment, and the protein kinases and phosphatases known to target these sites. We also include a detailed coverage of the complex changes in phosphorylation at specific titin residues, which have been reported in both animal models of heart disease and in human heart failure, and their correlation with titin‐based stiffness alterations. Knowledge of the relationship between titin PTMs and titin elasticity can be exploited in the search for therapeutic approaches aimed at softening the pathologically stiffened myocardium in heart failure patients. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Geophysical Research. Biogeosciences is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Common bean (Phaseolus vulgaris L.) is a nutritious crop grown around the world, a staple that provides high levels of protein and iron in the diets of Central and South Americans and East Africans. Heat stress negatively affects common bean seed yields and prevents cultivation in certain areas. Furthermore, under field conditions, heat stress often coincides with and exacerbates drought stress effects. Breeding more heat-tolerant cultivars would stabilize seed yield and open new regions to field production. To support these efforts, we examined a variety of methods for screening large numbers of bean germplasm exposed to heat stress at the vegetative growth stage as opposed to the reproductive stage, which would prolong the screening process. Tepary bean (P. acutifolius A. Gray), a closely related species to common bean, was used as a heatstress- tolerant check. Plants exposed to day/ night temperatures of 45/36°C for 2 d showed measurable signs of heat stress, but tepary bean outperformed the common beans on all stress tolerance measures. Gas exchange, chlorophyll fluorescence, and oxidative stress were only affected by this high temperature and not by temperatures below 45/36°C. Heat stress measurements also correlated well with visual signs of leaf tissue damage. Gradually raising temperatures was useful for screening large number of entries for heat tolerance, but this heat tolerance was only partially related to drought tolerance in the field. Plant breeders can use some of these methods to supplement field data and to further characterize the stress tolerance of bean lines. [ABSTRACT FROM AUTHOR]

Abstract: Die Herstellung Gerüst‐basierter, Gitter‐konstruierter 3D‐DNA‐Origami‐Strukturen ist eine aufstrebende, leistungsfähige und vielseitige Technik für die rationale Entwicklung nahezu beliebig strukturierter und monodisperser DNA‐basierter 3D‐Nanoobjekte. Basierend auf der unübertroffenen molekularen Programmierbarkeit der Sequenz‐spezifischen DNA‐Hybridisierung wird hierbei ein langer DNA‐Einzelstrang (Gerüststrang) mit vielen kurzen Einzelstrang‐Oligomeren (Faltungssträngen) zusammengefügt, die den Gerüststrang in einem Schritt zu einem 3D‐Gitter organisieren und so zu nanopartikulären 3D‐Strukturen führen. Die Zahl der Anwendungen von 3D‐DNA‐Origami nimmt stetig zu und steht mit zahlreichen Gebieten der Wissenschaft in Verbindung, z. B. mit anisometrisch strukturierten oder anisotrop funktionalisierten Nanopartikeln, grundlegenden Untersuchungen zur Überstrukturbildung, der Biomedizin und (Bio‐)Physik sowie mit der Sensorik und der Gestaltung optischer Materialien. Dieser Kurzaufsatz diskutiert die Grundlagen und jüngsten Fortschritte, von der Strukturbildung bis zu ausgewählten Anwendungen, und legt dabei den Fokus auf die Förderung eines interdisziplinären Austausches. [ABSTRACT FROM AUTHOR]

Abstract: Scaffold‐based lattice‐engineered 3D DNA origami is a powerful and versatile technique for the rational design and build‐up of arbitrarily structured and monodisperse DNA‐based 3D nanoobjects. Relying on the unsurpassed molecular programmability of sequence‐specific DNA hybridization, a long DNA single strand (termed scaffold) is assembled with many short single‐stranded oligomers (termed staples), which organize the scaffold into a 3D lattice in a single step, thereby leading to 3D nanoparticulate structures of the highest precision in high yields. Applications of 3D DNA origami are increasingly wide‐spread and interface with numerous fields of sciences, for example, anisometric or anisotropically functionalized nanoparticles, fundamental investigations of superstructure formation, biomedicine, (bio)physics, sensors, and optical materials. This Minireview discusses the fundamentals and recent advances from structure formation to selected applications, with a mission to promote cross‐disciplinary exchange. [ABSTRACT FROM AUTHOR]

Abstract: Reducing crop losses due to abiotic stresses is a major target of agricultural biotechnology that will increase with climate change and global population growth. Concerns, however, have been raised about potential ecological impacts if transgenes become established in wild populations and cause increased competitiveness of weedy or invasive species. Potential risks will be a function of transgene movement, population sizes, and fitness effects on the recipient population. While key components influencing gene flow have been extensively investigated, there have been few studies on factors subsequent to transgene movement that can influence persistence and competitiveness. Here, we performed multiyear, multigenerational, assessment to examine fitness effects and persistence of three mechanistically different abiotic stress tolerance genes: C‐repeat binding factor 3/drought responsive element binding factor 1a (CBF3/DREB1a); Salt overly sensitive 1 (SOS1); and Mannose‐6‐phosphate reductase (M6PR). Transgenic Arabidopsis thaliana overexpressing these genes were grown in pure populations and in competition with wild‐type (WT) parents for six generations spanning a range of field environment conditions. Growth, development, biomass, seed production, and transgene frequency were measured at each generation. Seed planted for each generation was obtained from the previous generation as would occur during establishment of a new genotype in the environment. The three transgenes exhibited different fitness effects and followed different establishment trajectories. In comparison with pure populations, CBF3 lines exhibited reduced dry weight, seed yield, and viable seed yield, relative to WT background. In contrast, overexpression of SOS1 and M6PR did not significantly impact productivity measures in pure populations. In competition with WT, negative fitness effects were magnified. Transgene frequencies were significantly reduced for CBF3 and SOS1 while frequencies of M6PR appeared to be subject to genetic drift. These studies demonstrate the importance of fitness effects and intergenotype competition in influencing persistence of transgenes conferring complex traits. [ABSTRACT FROM AUTHOR]

Core Ideas: We present a semiautomated framework for large‐scale calibration of capacitance soil moisture sensors.Soil‐specific calibrations are needed for accurate moisture measurements in nearly all soil types.Transparent, traceable, and complete uncertainty estimates provided for entire approach. Technological advances have allowed in situ monitoring of soil water content in an automated manner. These advances, along with an increase in large‐scale networks monitoring soil water content, stress the need for a robust calibration framework that ensures that soil water content measurements are accurate and reliable. We have developed an approach to make consistent and comparable soil water content sensor calibrations across a continental‐scale network in a production framework that incorporates a thorough accounting of uncertainties. More than 150 soil blocks of varying characteristics from 33 locations across the United States were used to generate soil‐specific calibration coefficients for a capacitance sensor. We found that the manufacturer's nominal calibration coefficients poorly fit the data for nearly all soil types. This resulted in negative (91% of samples) and positive (5% of samples) biases and a mean root mean square error (RMSE) of 0.123 cm3 cm−3 (1σ) relative to reference standard measurements. We derived soil‐specific coefficients, and when used with the manufacturer's nominal function, the biases were corrected and the mean RMSE dropped to ±0.017 cm3 cm−3 (±1σ). A logistic calibration function further reduced the mean RMSE to ±0.016 cm3 cm−3 (±1σ) and increased the range of soil moistures to which the calibration applied by 18% compared with the manufacturer's function. However, the uncertainty of the reference standard was notable (±0.022 cm3 cm−3), and when propagated in quadrature with RMSE estimates, the combined uncertainty of the calibrated volumetric soil water content values increased to ±0.028 cm3 cm−3 regardless of the calibration function used. [ABSTRACT FROM AUTHOR]

Changes in tropical forest carbon sink strength during El Niño Southern Oscillation ( ENSO) events can indicate future behavior under climate change. Previous studies revealed ˜6 Mg C ha−1 yr−1 lower net ecosystem production ( NEP) during ENSO year 1998 compared with non- ENSO year 2000 in a Costa Rican tropical rainforest. We explored environmental drivers of this change and examined the contributions of ecosystem respiration ( RE) and gross primary production ( GPP) to this weakened carbon sink., For 1998-2000, we estimated RE using chamber-based respiration measurements, and we estimated GPP in two ways: using (1) the canopy process model MAESTRA, and (2) combined eddy covariance and chamber respiration data. MAESTRA-estimated GPP did not statistically differ from GPP estimated using approach 2, but was ˜ 28% greater than published GPP estimates for the same site and years using eddy covariance data only., A 7% increase in RE (primarily increased soil respiration) and a 10% reduction in GPP contributed equally to the difference in NEP between ENSO year 1998 and non- ENSO year 2000., A warming and drying climate for tropical forests may yield a weakened carbon sink from both decreased GPP and increased RE. Understanding physiological acclimation will be critical for the large carbon stores in these ecosystems. [ABSTRACT FROM AUTHOR]

Common bean (Phaseolus vulgaris L.) is an important food crop, especially in East Africa and Central and South America. Subsistence farmer yields in these areas are limited by the many common bean cultivars that are drought sensitive. Consequently, a major goal of breeding programs is to improve drought tolerance. Our objective was to identify and compare physiological components of drought stress among common bean genotypes varying in stress tolerance. We also included the closely related and highly stress-tolerant tepary bean (P. acutifolius A. Gray). Compositional parameters often related to drought tolerance revealed no drought effect on free proline, but malate, glucose, fructose, inositol, and raffinose all increased, sometimes enough to osmotically adjust leaf tissues. Abscisic acid (ABA) was especially drought responsive. Although geno-typic differences were unrelated to tolerance, grafting revealed that shoot identity controlled ABA levels in stressed roots and that root identity had little or no effect on stomatal behavior. Photosynthetic parameters derived from photosynthesis versus intercellular CO2 concentration curves were not related to drought tolerance, but some traits were related to productivity. Stomatal control and low conductance were clearly associated with tolerance, conserving water during stress, and increasing water use efficiencies. This study should provide guidance in selection of traits associated with enhanced drought tolerance in common bean. [ABSTRACT FROM AUTHOR]

Background Cerebral hemiatrophy syndromes can present with variable neurological symptoms. In childhood epilepsy, mental retardation and neuropsychiatric disorders are common while in adults movement disorders, such as highly asymmetric parkinsonism or hemidystonia as well as neuropsychiatric problems have been reported. Methods Here, we present three adult patients with features that expand the clinical spectrum and give an overview of the most common clinical signs associated with this rare condition. Results All three patients had prominent neuropsychiatric symptoms such as mood swings and increased irritability. Furthermore, one patient developed hemichorea which can be a rare presentation of cerebral hemiatrophy. Conclusions Cerebral hemiatrophy syndromes are a heterogeneous group of disorders that may also present with neuropsychiatric symptoms or hemichorea. [ABSTRACT FROM AUTHOR]

The article discusses the engagement and planning model for the operation of the National Ecological Observatory Network (NEON) infrastructure project which was funded by the National Science Foundation (NSF). Topics discussed include the advocacy of National Academy of Science on environmental science, biogeochemistry, and climate change, the expenditures and budget for NEON, and the engagement of research, scientific and educational communities to the NEON programs.

Visible-light-mediated photoredox-catalyzed aldimine-aniline and aldehyde-aniline couplings have been realized. The reductive single electron transfer (SET) umpolung of various carbonyl derivatives enabled the generation of intermediary ketyl and α-amino radical anions, which were utilized for the synthesis of unsymmetrically substituted 1,2-diamines and amino alcohols. [ABSTRACT FROM AUTHOR]

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Ketyl radical and amino radical anions, valuable reactive intermediates for CC bond-forming reactions, are accessible through a CO/CNR umpolung. However, their utilization in catalysis remains largely underdeveloped owing to the high reduction potential of carbonyl compounds and imines. In the context of photoredox catalysis, tertiary amines are commonly employed as sacrificial co-reducing agents. Herein, an additional role of the amine is proposed, in which it is essential for the organocatalytic substrate activation. The combination of photoredox catalysis and carbonyl/imine activation enables the reductive coupling of aldehydes, ketones, and imines under mild reaction conditions. [ABSTRACT FROM AUTHOR]

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Net CO2 exchange data of legume crops at 17 flux tower sites in North America and three sites in Europe representing 29 site-years of measurements were partitioned into gross photosynthesis and ecosystem respiration by using the nonrectangular hyperbolic light-response function method. The analyses produced net CO2 exchange data and new ecosystem-scale ecophysiological parameter estimates for legume crops determined at diurnal and weekly time steps. Dynamics and annual totals ofgross photosynthesis, ecosystem respiration, and net ecosystem production were calculated by gap filling with multivariate nonlinear regression. Comparison with the data from grain crops obtained with the same method demonstrated that CO2 exchange rates and ecophysiological parameters of legumes were lowerthan those of maize (ZeamaysL.) but higherthanforwheat (TriticumaestipumL.) crops. Year-round annuallegume crops demonstrated a broad range of net ecosystem production, from sinks of 760 g CO2 m-2 yr-1 to sources of -2100 g CO2 m-2 yr-1, with an average of -330 g CO2 m-2 yr-1, indicating overall moderate CO2-source activity related to a shorter period of photosynthetic uptake and metabolic costs of N2 fixation. Perennial legumes (alfalfa, Medicago sativa L.) were strong sinks for atmospheric CO2, with an average net ecosystem production of 980 (range 550-1200) g CO2 m-2 yr-1. [ABSTRACT FROM AUTHOR]

Newly developed perennial cereals have been developed as alternatives to annual food crops. These provide novel contexts in which to study source vs. sink limitations of plant productivity. This is one of the first investigations of source:sink effects on photosynthesis, seed size, and regrowth in perennial cereal crops as well as in the commercially important annual rye (Secale cereale L.). Through experimental manipulations of field-grown plants, we studied the effect of manipulations of source:sink ratio (25% decreases and 100% increases) on photosynthetic rate in perennial wheat [Triticum aestivum L. × Thinopyrum elongatum (Host) D. R. Dewey], perennial rye [S. cereale × Secale strictum (C. Presl) C. Presl subsp. strictum (syn. Secale montanum Guss.)], annual wheat (Triticum aestivum L.), and annual rye. We measured carbohydrate pools, seed size, and regrowth as further indices of source vs. sink limitation. Perennial wheat showed sink limitation throughout. Annual and perennial rye appeared to be colimited. Low source:sink ratios in perennial wheat and rye were associated with up to 25% higher photosynthetic rates while high source:sink ratios led to up to 20% decreases. Seed size showed more stability under source:sink manipulation in perennials than in annuals while regrowth of perennials was not affected by source sink ratio, and all three species showed more stability of seed size in response to source:sink manipulation than annual wheat. Our results are consistent with perennial cereals operating below their maximum photosynthetic capacity, in contrast to annual wheat, and following a conservative reproductive strategy. By selecting for greater sink strength in perennial wheat, breeders may be able to achieve higher rates of photosynthesis and support higher yields in this new crop. [ABSTRACT FROM AUTHOR]

Purpose We systematically reviewed current literature on parent role modeling of healthy eating and physical activity as a strategy to influence healthy weight of middle school-age African American children. Conclusions The evidence for parent role modeling is low to average. Most studies did not target African American participants or middle school-age children. Practice Implications Nurses can begin to remedy deficient knowledge of parent role modeling by assessing parent attitudes, beliefs, and healthy behaviors, as well as the children's. Existing dietary and physical activity guidelines are not specific to African Americans but can be a starting point for educating parents. [ABSTRACT FROM AUTHOR]

ABSTRACT Introduction Echinacea preparations are among the most popular herbal remedies worldwide. Although it is generally assigned immune enhancement activities, the effectiveness of Echinacea is highly dependent on the Echinacea species, part of the plant used, the age of the plant, its location and the method of extraction. Objective The aim of this study was to investigate the capacity of an artificial neural network (ANN) to analyse thin-layer chromatography (TLC) chromatograms as fingerprint patterns for quantitative estimation of three phenylpropanoid markers (chicoric acid, chlorogenic acid and echinacoside) in commercial Echinacea products. Material and methods By applying samples with different weight ratios of marker compounds to the system, a database of chromatograms was constructed. One hundred and one signal intensities in each of the TLC chromatograms were correlated to the amounts of applied echinacoside, chlorogenic acid and chicoric acid using an ANN. Results The developed ANN correlation was used to quantify the amounts of three marker compounds in Echinacea commercial formulations. The minimum quantifiable level of 63, 154 and 98 ng and the limit of detection of 19, 46 and 29 ng were established for echinacoside, chlorogenic acid and chicoric acid respectively. Conclusion A novel method for quality control of herbal products, based on TLC separation, high-resolution digital plate imaging and ANN data analysis has been developed. The method proposed can be adopted for routine evaluation of the phytochemical variability in Echinacea formulations available in the market. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The southeastern United States is an economically important agricultural region, yet its role in the regional C budget is not fully understood. There is concern that climate change, particularly altered precipitation patterns, may induce a shift in how crops exchange CO2 with the atmosphere. This study examined the seasonal and interannual variation in net ecosystem exchange (NEE) of a winter wheat cover crop (Triticum aestivum L.) and soybean [Glycine max (L.) Merr.] using the eddy covariance (EC) method. This was conducted at Winfred Thomas Agricultural Research Station, Hazel Green, AL (2007-2009). Annual C balance ranged from a source in 2007 (NEE = 100 g C m-2 yr-1 ) to a sink (-20 g C m-2 yr-1) in 2009. Annual ecosystem respiration (RJ ranged between 750 and 1013 g C m-2 yr-1, while gross ecosystem productivity was between 650 and 1034 g C m-2 yr-1. Seasonal NEE for soybean ranged between 42 and -66 g C m-2 . The uptake rates from the cover crop (NEE = -80.0, -80.4, and -40.0 g C m-2 for 2007, 2008, and 2009, respectively) suggested the importance of winter C uptake offsetting C losses caused by summer droughts. The Re varied between 286 and 542 g C m-2 for soybean and between 160 and 313 g C m-2 for the cover crop. Annual variations in NEE and Re were primarily due to precipitation and air temperature, respectively, indicating a tight coupling between biophysical factors and C uptake. Our results were compared with those from other reported NEE crop estimates using EC. [ABSTRACT FROM AUTHOR]

Summary Engineered abiotic stress resistance is an important target for increasing agricultural productivity. There are concerns, however, regarding possible ecological impacts of transgenic crops. In contrast to the first wave of transgenic crops, many abiotic stress resistance genes can initiate complex downstream changes. Transcriptome profiling has been suggested as a comprehensive non-targeted approach to examine the secondary effects. We compared phenotypic and transcriptomic effects of constitutive expression of genes intended to confer salt stress tolerance by three different mechanisms: a transcription factor, CBF3/DREB1a; a metabolic gene, M6PR, for mannitol biosynthesis; and the Na+/H+ antiporter, SOS1. Transgenic CBF3, M6PR and SOS1 Arabidopsis thaliana were grown together in the growth chamber, greenhouse and field. In the absence of salt, M6PR and SOS1 lines performed comparably with wild type; CBF3 lines exhibited dwarfing as reported previously. All three transgenes conferred fitness advantage when subjected to 100 m m NaCl in the growth chamber. CBF3 and M6PR affected transcription of numerous abiotic stress-related genes as measured by Affymetrix microarray analysis. M6PR additionally modified expression of biotic stress and oxidative stress genes. Transcriptional effects of SOS1 in the absence of salt were smaller and primarily limited to redox-related genes. The extent of transcriptome change, however, did not correlate with the effects on growth and reproduction. Thus, the magnitude of global transcriptome differences may not predict phenotypic differences upon which environment and selection act to influence fitness. These observations have implications for interpretation of transcriptome analyses in the context of risk assessment and emphasize the importance of evaluation within a phenotypic context. [ABSTRACT FROM AUTHOR]

Planted pine forests (plantations) in the southeastern United States are an important component of the continent's carbon balance. Forest carbon dynamics are affected by a range of factors including climatic variability. Multiyear droughts have affected the region in the past, and an increase in the frequency of drought events has been predicted. How this increased climatic variability will affect the capacity of the region's pine plantations to sequester carbon is not known. We used eddy covariance and biometric approaches to measure carbon dynamics over nine years in two slash pine plantations (Pinus elliottii var elliottii Englm) in north Florida, consisting of a newly planted and a mid-rotation stand. During this time, the region experienced two multiyear droughts (1999--2002 and 2006--2008), separated by a three-year wet period. Net ecosystem carbon accumulation measured using both approaches showed the same trends and magnitudes during plantation development. The newly planted site released 15.6 Mg C/ha during the first three years after planting, before becoming a carbon sink in year 4. Increases in carbon uptake during the early stages of stand development were driven by the aggrading leaf area index (LAI). After canopy closure, both sites were continuous carbon sinks with net carbon uptake (NEE) fluctuating between 4 and ~8Mg C⋅ha-1⋅yr-1, depending on environmental conditions. Drought reduced NEE by ~25% through its negative effects on both LAI and radiation-use efficiency, which resulted in a larger impact on gross ecosystem carbon exchange than on ecosystem respiration. While results indicate that responses to drought involved complex interactions among water availability, LAI, and radiation-use efficiency, these ecosystems remain carbon sinks under current management strategies and climatic variability. Variation within locations is primarily due to major disturbances, such as logging in the current study and, to a much lesser extent, local environmental fluctuations. When data from this study are compared to flux data from a broad range of forests worldwide, these ecosystems fill a data gap in the warm-temperate zone and support a broad maximum NEE (for closed-canopy forests) between 8°C and 20°C mean annual temperature. [ABSTRACT FROM AUTHOR]

Purpose: Little is known about the skin cancer detection skills of advanced practice nurses (APNs). This systematic review of published literature seeks to describe (a) barriers to APNs' performance of skin examination, (b) APNs' ability to recognize suspicious skin lesions, and (c) APNs' skin cancer detection training activities. Data sources: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement guided the literature search (OVID Medline, Web of Science, and CINAHL databases) and interpretation of findings. Of the 136 articles meeting criteria for selection, 12 pertaining to the purpose were selected for further review. Conclusions: Barriers to skin examination by APNs have been infrequently and inconsistently measured. Limited time to conduct skin examination is the most consistent barrier. APNs' ability to recognize and refer suspicious and benign lesions is inconsistent, but shows improvement after training. Few skin cancer training programs are available for APNs. Implications: Larger and more rigorously designed studies are needed to better determine APNs' barriers and facilitators to skin cancer assessment and their ability to recognize and appropriately refer potentially malignant skin lesions with a high level of sensitivity and specificity. Training to increase these skills needs to be targeted to APNs and occur at a much higher volume than current efforts. [ABSTRACT FROM AUTHOR]

Microsurgical repair of transected peripheral nerves is compromised by the formation of scar tissue and the development of a neuroma, thereby limiting the success of regeneration. The aim of this study was to quantify histomorphometrically the structural changes in neural tissue that result from repair, and determine the effect of mannose-6-phosphate (M6P), a scar-reducing agent previously shown to enhance regeneration. In anaesthetised C57-black-6 mice, the left sciatic nerve was sectioned and repaired using four epineurial sutures. Either 100 μL of 600 m m M6P (five animals) or 100 μL of phosphate-buffered saline (placebo controls, five animals) was injected into and around the nerve repair site. A further group acted as sham-operated controls. After recovery for 6 weeks, the nerve was harvested for analysis using light and electron microscopy. Analysis revealed that when compared with sham controls, myelinated axons had smaller diameters both proximal and distal to the repair. Myelinated axon counts, axonal density and size all decreased across the repair site. There were normal numbers and densities of non-myelinated axons both proximal and distal to the repair. However, there were more Remak bundles distal to the repair site, and fewer non-myelinated axons per Remak bundle. Application of M6P did not affect any of these parameters. [ABSTRACT FROM AUTHOR]

The landscape surface of the Barrow Peninsula of Alaska is a mosaic of small ponds, thaw lakes, different aged vegetated drained thaw-lake basins (VDTLBs), and interstitial tundra which have been dynamically formed by both short- and long-term processes. We used a combination of tower- and aircraft-based eddy covariance measurements to characterize the spatial and temporal patterns of CO2, latent, and sensible heat fluxes along with MODIS NDVI, and were able to scale the aircraft-based CO2 fluxes to the 1802 km2 Barrow Peninsula region. During typical 2006 summer conditions, the midday hourly CO2 flux over the region was −2.04 × 105 kg CO2 h−1. The CO2 fluxes among the interstitial tundra, Ancient, and Old VDTLBs, as well as between the Medium and Young VDTLBs were not significantly different. Combined, the interstitial tundra and Old and Ancient VDTLBs represent∼67% of the Barrow Peninsula surface area, accounting for ∼59% of the regional flux signal. Although the Medium and Young VDTLBs represent ∼11% of the surface area, they account for a large portion, ∼35%, of the total regional flux. The remaining ∼22% of the surface area are lakes and contributed the remaining ∼6% of the total regional flux. Previous studies treated vegetated areas of the region as a single surface type with measurements from a few study sites; doing so could underestimate the regional flux by ∼22%. Here, we demonstrate that aircraft-based systems have the ability to cover large spatial scales while measuring the turbulent fluxes across a number of surfaces and combined with ground- and satellite-based measurements provide a valuable tool for both scaling and validation of regional-scale fluxes. [ABSTRACT FROM AUTHOR]

Tropical vegetation is a major source of global land surface evapotranspiration, and can thus play a major role in global hydrological cycles and global atmospheric circulation. Accurate prediction of tropical evapotranspiration is critical to our understanding of these processes under changing climate. We examined the controls on evapotranspiration in tropical vegetation at 21 pan-tropical eddy covariance sites, conducted a comprehensive and systematic evaluation of 13 evapotranspiration models at these sites, and assessed the ability to scale up model estimates of evapotranspiration for the test region of Amazonia. Net radiation was the strongest determinant of evapotranspiration (mean evaporative fraction was 0.72) and explained 87% of the variance in monthly evapotranspiration across the sites. Vapor pressure deficit was the strongest residual predictor (14%), followed by normalized difference vegetation index (9%), precipitation (6%) and wind speed (4%). The radiation-based evapotranspiration models performed best overall for three reasons: (1) the vegetation was largely decoupled from atmospheric turbulent transfer (calculated from Ω decoupling factor), especially at the wetter sites; (2) the resistance-based models were hindered by difficulty in consistently characterizing canopy (and stomatal) resistance in the highly diverse vegetation; (3) the temperature-based models inadequately captured the variability in tropical evapotranspiration. We evaluated the potential to predict regional evapotranspiration for one test region: Amazonia. We estimated an Amazonia-wide evapotranspiration of 1370 mm yr−1, but this value is dependent on assumptions about energy balance closure for the tropical eddy covariance sites; a lower value (1096 mm yr−1) is considered in discussion on the use of flux data to validate and interpolate models. [ABSTRACT FROM AUTHOR]

Interannual variation of carbon fluxes can be attributed to a number of biotic and abiotic controls that operate at different spatial and temporal scales. Type and frequency of disturbance, forest dynamics, and climate regimes are important sources of variability. Assessing the variability of carbon fluxes from these specific sources can enhance the interpretation of past and current observations. Being able to separate the variability caused by forest dynamics from that induced by climate will also give us the ability to determine if the current observed carbon fluxes are within an expected range or whether the ecosystem is undergoing unexpected change. Sources of interannual variation in ecosystem carbon fluxes from three evergreen ecosystems, a tropical, a temperate coniferous, and a boreal forest, were explored using the simulation model STANDCARB. We identified key processes that introduced variation in annual fluxes, but their relative importance differed among the ecosystems studied. In the tropical site, intrinsic forest dynamics contributed ∼30% of the total variation in annual carbon fluxes. In the temperate and boreal sites, where many forest processes occur over longer temporal scales than those at the tropical site, climate controlled more of the variation among annual fluxes. These results suggest that climate-related variability affects the rates of carbon exchange differently among sites. Simulations in which temperature, precipitation, and radiation varied from year to year (based on historical records of climate variation) had less net carbon stores than simulations in which these variables were held constant (based on historical records of monthly average climate), a result caused by the functional relationship between temperature and respiration. This suggests that, under a more variable temperature regime, large respiratory pulses may become more frequent and high enough to cause a reduction in ecosystem carbon stores. Our results also show that the variation of annual carbon fluxes poses an important challenge in our ability to determine whether an ecosystem is a source, a sink, or is neutral in regard to CO2 at longer. timescales. In simulations where climate change negatively affected ecosystem carbon stores, there was a 20% chance of committing Type II error, even with 20 years of sequential data. [ABSTRACT FROM AUTHOR]

Axonal regeneration at a site of peripheral nerve repair can be impeded by the formation of scar tissue, which creates a mechanical barrier and initiates the development of multiple branched axonal sprouts that form a neuroma. We have investigated the hypothesis that the application of a scar-reducing agent to the nerve repair site would permit better axonal regeneration. In anaesthetised C57 Black-6 mice, the left sciatic nerve was sectioned and immediately re-approximated using four epineurial sutures. In five groups of eight mice, we injected transforming growth factor-β3 (50 or 500 ng), interleukin-10 (IL-10) (125 or 500 ng), or saline into and around the repair site, both before and after the nerve section. Another group of eight animals acted as sham-operated controls. After 6 weeks, the outcome was assessed by recording compound action potentials (CAPs), measuring collagen levels using picrosirius red staining, and counting the number of myelinated axons proximal and distal to the repair. CAPs evoked by electrical stimulation distal to the repair were significantly smaller in all repair groups except for the low-dose IL-10 group, where they were not significantly different from that in controls. The area of staining for collagen had significantly increased in all repair groups except for the low-dose IL-10 group, which was not significantly different from that in controls. The myelinated fibre counts were always higher distal to the repair site, but there were no significant differences between groups. We conclude that administration of a low-dose of IL-10 to a site of sciatic nerve repair reduces scar formation and permits better regeneration of the damaged axons. [ABSTRACT FROM AUTHOR]