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Background: Many instructors transitioned their courses from face‐to‐face environments to computer‐mediated learning environments (CMLEs) following the onset of the coronavirus disease 2019 (COVID‐19) pandemic. However, little was known about how teleconferencing platforms and their corresponding functions affect student learning when the COVID‐19 pandemic began. Objectives: The aim of this study was to provide more clarity on the conditions through which online teleconferencing platforms influence student achievement. More specifically, this study investigated how displaying lecture‐relevant and lecture‐irrelevant messages in a chat box during a video lecture delivered via the Zoom teleconferencing platform affected student learning and note taking. Methods: Participants viewed the video lecture either with (relevant or irrelevant) or without messages appearing in the chat box of the Zoom window. Participants completed a learning test immediately following the lecture. Results and Conclusions: No difference regarding student achievement was observed between the three groups. However, results revealed that students in the relevant‐lecture messages group reported a higher extraneous cognitive load than the other groups even if they reported positive attitudes about the messages appearing on the chat box. Students in the lecture‐relevant group also recorded more notes during the lecture compared to the two other groups, but this result did not reach significance. This study extends previous research that investigated how messaging influences learning in classroom settings. Findings suggest that allowing relevant discussions is not the best strategy to promote learning in CMLEs as this information seems to compete with the other relevant information being presented during the ongoing lecture. Lay Description: What is already known about this topic: In video lectures, the chat box has been identified as the function most often used to support students' learning.Responding to lecture‐relevant messages can enhance students' learning.However, it remains unknown how simply reading, but not responding to, lecture‐relevant and lecture‐irrelevant messages can affect learning and note taking. What this paper adds: In previous studies, researchers examined how messaging affects learning in a classroom setting, but not within a computer‐mediated lecture environment.The present study extends previous research that investigated how messaging influences learning in classroom settings.This study provides more clarity on the conditions through which online teleconferencing platforms affect student learning and note taking.Findings suggest that allowing relevant discussions is not the best strategy to promote learning in CMLEs as this information seems to compete with the other relevant information being presented during the ongoing lecture. Implications for practitioners: The features of video lectures are critical factors, as they influence students' learning and should therefore be taken into account when designing educational materials.Instructors should not allow students to engage in lecture‐relevant and irrelevant messaging and discussion during video lectures as it competes with the other relevant information being presented. [ABSTRACT FROM AUTHOR]

In this paper, the analytical investigation of non‐Newtonian fluid flow through a turbine disc with a heat generation effect is considered. The flow mechanics through the turbine disc is modeled using a coupled system of higher‐order partial equations, which are transformed into ordinary order utilizing proper similarity transforms. Governing models are analyzed using the variation iteration and homotopy perturbation analytical methods. As observed from the results, the study shows enhancement of heat generation for non‐Newtonian fluid flow through turbine disc, reveals abating thermal distribution. More so, the graphical expression shows that heat generation improves up till mid‐disc. Thereafter, an increasing trend toward the fluid injection surface is observed. Validation of analytical solutions with numerical analysis boosts confidence in this study, which may be used to provide further insights into the engineering science of non‐Newtonian flow of hydraulic/lube oil in practical applications, such as hydraulic couplings. [ABSTRACT FROM AUTHOR]

Thinning of semi‐arid forests to reduce wildfire risk is believed to improve forest health by increasing soil moisture. Increased snowpack, reduced transpiration and reduced rainfall interception are frequently cited mechanisms by which reduced canopy density may increase soil moisture. However, the relative importance of these factors has not been rigorously evaluated in field studies. We measured snow depth, snow water equivalent (SWE) and the spatial and temporal variation in soil moisture at four experimental paired treatment‐control thinning sites in high elevation ponderosa pine forest northern Arizona, USA. We compared snow and soil moisture measurements with forest structure metrics derived from aerial imagery and 3‐dimensional lidar data to determine the relationship between vegetation structure, snow and soil moisture throughout the annual hydrologic cycle. Soil moisture was consistently and significantly higher in thinned forest plots, even though the treatments were performed 8–11 years before this study. However, we did not find evidence that SWE was higher in thinned forests across a range of snow conditions. Regression tree analysis of soil moisture and vegetation structure data provided some evidence that localized differences in transpiration and interception of precipitation influence the spatial pattern of soil moisture at points in the annual hydrologic cycle when the system is becoming increasingly water limited. However, vegetation structure explained a relatively low amount of the spatial variance (R2 < 0.23) in soil moisture. Continuous measurements of soil moisture in depth profiles showed stronger attenuation of soil moisture peaks in thinned sites, suggesting differences in infiltration dynamics may explain the difference in soil moisture between treatments as opposed to overlying vegetation alone. Our results show limited support for commonly cited relationships between vegetation structure, snow and soil moisture and indicate that future research is needed to understand how reduction in tree density alters soil hydraulic properties. [ABSTRACT FROM AUTHOR]

Enhance spring and aquifer information management, for example, by linking biological, cultural, and management values and characteristics to data on the geographic distribution, functional and ecological integrity, and vulnerability to human impacts of springs and aquifers. In recent decades, for example, aquifer overdraft related to rapid human population growth and agricultural irrigation dewatered 195 of 861 known springs in Jordan: total annual spring discharge decreased from 250 × 10 SP 6 sp m SP 3 sp in 1970 to 135 × 10 SP 6 sp m SP 3 sp today (Fig. Springs are natural discharge points from aquifers and the origin of diverse surface-water systems (Glazier 2014; Junghans et al. 2016) (Fig. Among these, the Habitat Directive (Annex I) of the European Union (EU) recognizes only one major spring habitat type, namely Limestone Precipitating Springs (EU-Code 7220); all other types are not considered worthy of protection. [Extracted from the article]

Springs ecosystems are globally abundant, geomorphologically diverse, and bio‐culturally productive, but are highly imperiled by anthropogenic activities. More than a century of scientific discussion about the wide array of ecohydrological factors influencing springs has been informative, but has yielded little agreement on their classification. This lack of agreement has contributed to the global neglect and degradation of springs ecosystems by the public, scientific, and management communities. Here we review the historical literature on springs classification variables, concluding that site‐specific source geomorphology remains the most diagnostic approach. We present a conceptual springs ecosystem model that clarifies the central role of geomorphology in springs ecosystem development, function, and typology. We present an illustrated dichotomous key to terrestrial (non‐marine) springs ecosystem types and subtypes, and describe those types. We identify representative reference sites, although data limitations presently preclude selection of continentally or globally representative reference springs of each type. We tested the classification key using data from 244 randomly selected springs of 13 types that were inventoried in western North America. The dichotomous key correctly identified springs type in 87.5% of the cases, with discrepancies primarily due to differentiation of primary vs. secondary typology, and insufficient inventory team training. Using that information, we identified sources of confusion and clarified the key. Among the types that required more detailed explanation were hypocrenes, springs in which groundwater is expressed through phreatophytic vegetation. Overall, springs biodiversity and ecosystem complexity are due, in part, to the co‐occurrence of multiple intra‐springs microhabitats. We describe microhabitats that are commonly associated with different springs types, reporting at least 13 microhabitats, each of which can support discrete biotic assemblages. Interdisciplinary agreement on basic classification is needed to enhance scientific understanding and stewardship of springs ecosystems, the loss and degradation of which constitute a global conservation crisis. [ABSTRACT FROM AUTHOR]

Biometric authentication technology are being increasingly used for many applications. Since such technology requires high level human interaction, effective implementation and acceptability of such system depends on users' perception, particularly, in the area of system safety and privacy. This study was conducted using a survey design accomplished through the use of a descriptive rating, Likert‐type survey instrument. Quantitative data were collected from participants in four tertiary academic institutions and Statistical Package for Social Science version 23 was used for data analysis. The survey focuses on three universities and a polytechnic situated in Kaduna metropolis. Deliberate sampling technique was used in selecting the four academic institutions, stratified random sampling technique was used in administering the survey instrument to 50 respondents from each institutions. The survey sampled 200 participants. Result from the study revealed the importance of considering users' perception before the implementation of biometric system. Major factors that significantly influence perception in this study are users' knowledge of biometric system and gender. Furthermore, 99.5% of the respondents show that public enlightenment and formulation of appropriate legal guidelines to back the use of biometric information will instil confidence in users of biometric technology. [ABSTRACT FROM AUTHOR]

Natural springs in water‐limited landscapes are biodiversity hotspots and keystone ecosystems that have a disproportionate influence on surrounding landscapes despite their usually small size. Some springs served as evolutionary refugia during previous climate drying, supporting relict species in isolated habitats. Understanding whether springs will provide hydrologic refugia from future climate change is important to biodiversity conservation but is complicated by hydrologic variability among springs, data limitations, and multiple non‐climate threats to groundwater‐dependent ecosystems. We present a conceptual framework for categorizing springs as potentially stable, relative, or transient hydrologic refugia in a drying climate. Clues about the refugial capacity of springs can be assembled from various approaches, including citizen‐science‐powered ecohydrologic monitoring, remote sensing, landowner interviews, and environmental tracer analysis. Managers can integrate multiple lines of evidence to predict which springs may become future refugia for species of concern, strengthening the long‐term effectiveness of their conservation and restoration, and informing climate adaptation for terrestrial and freshwater species. [ABSTRACT FROM AUTHOR]

Terrestrial laser scanners (TLSs) provide a tool to assess and monitor forest structure across forest landscapes. We present TLS methods, suggestions, and mapped guidelines for planning TLS acquisitions at varying scales and forest densities. We examined rates of point‐density decline with distance from two TLS that acquire data at relatively high and low point density and found that the rates were nearly identical between scanners (p value <0.01), suggesting that our findings are applicable to a range of TLS types. Using unique, TLS‐adapted processing methods, we determined the relative accuracy of TLS‐derived plot‐scale estimates of tree height, diameter‐at‐breast‐height, height‐to‐canopy, tree counts, as well as treatment‐scale tree density and patch metrics, using both high point density and low point density TLS among thinned and nonthinned forest treatments. The high‐density TLS consistently provides more accurate estimates of plot‐level metrics (R2 = 0.46 to 0.87) than the low‐density TLS (R2 = −0.14 to 0.53). At treatment scales, tree density estimates are similar among scanners (R2 = 0.95 vs. 0.71), as are canopy cover and patch metrics. We develop and present the normalized density‐distance index (NDDI), which can account for up to 59% of the variance in estimate error and can be used to guide TLS‐data acquisition plans. This index indicates whether a given location has generally higher point density (higher NDDI) relative to the distance from the scanner and can be used as a proxy for uncertainty. Using NDDI as a guide for fair comparison between scanners, both plot‐ and treatment‐scale estimates improved. Plain Language Summary: We compared two ground‐based lidar instruments, an expensive unit that captures dense data and a constructed, inexpensive unit that produces relatively low‐density data. We wanted to understand how well these units capture forest structure, including tree heights, diameters, and canopy cover as well as how to better place these scanners on a landscape to capture better data. We found that the more expensive lidar better captures forest attributes at small landscape scales, but the difference between the two diminishes as you reach larger spatial scales. We also found that the rate at which the point density declines is approximately the same between the two lidars, suggesting that these findings are applicable across a range of ground‐based lidar instruments. Finally, we came up with suggestions and some mapped guidelines on how to best arrange lidar instruments across a landscape in which the density of trees is variable. The methods we use here are applicable many types of forest‐related questions, including biomass, carbon capture, and growth through time. Key Points: TLS can provide accurate forest structure metrics below the canopy across a range of spatial extentsHigh‐density TLS is needed for most metrics, while low‐density TLS provides reasonable estimates of canopy height and tree densityMultiple lines of evidence are used to determine optimal scanner‐location schemes for data collection among variable forest density [ABSTRACT FROM AUTHOR]

Abstract: Climate change and wildfire are interacting to drive vegetation change and potentially reduce water quantity and quality in the southwestern United States, Forest restoration is a management approach that could mitigate some of these negative outcomes. However, little information exists on how restoration combined with climate change might influence hydrology across large forest landscapes that incorporate multiple vegetation types and complex fire regimes. We combined spatially explicit vegetation and fire modeling with statistical water and sediment yield models for a large forested landscape (335,000 ha) on the Kaibab Plateau in northern Arizona, USA. Our objective was to assess the impacts of climate change and forest restoration on the future fire regime, forest vegetation, and watershed outputs. Our model results predict that the combination of climate change and high‐severity fire will drive forest turnover, biomass declines, and compositional change in future forests. Restoration treatments may reduce the area burned in high‐severity fires and reduce conversions from forested to non‐forested conditions. Even though mid‐elevation forests are the targets of restoration, the treatments are expected to delay the decline of high‐elevation spruce–fir, aspen, and mixed conifer forests by reducing the occurrence of high‐severity fires that may spread across ecoregions. We estimate that climate‐induced vegetation changes will result in annual runoff declines of up to 10%, while restoration reduced or reversed this decline. The hydrologic model suggests that mid‐elevation forests, which are the targets of restoration treatments, provide around 80% of runoff in this system and the conservation of mid‐ to high‐elevation forests types provides the greatest benefit in terms of water conservation. We also predict that restoration treatments will conserve water quality by reducing patches of high‐severity fire that are associated with high sediment yield. Restoration treatments are a management strategy that may reduce undesirable outcomes for multiple ecosystem services. [ABSTRACT FROM AUTHOR]

The increasing frequency and severity of landscape‐scale wildfire poses new challenges for forested watershed management. The Schultz Fire burned 6,100 ha on the steep slopes of San Francisco Mountain near Flagstaff, AZ, USA in 2010. Within a month of the wildfire, summer monsoon rains created flooding and debris flows 1–2 orders of magnitude greater than prewildfire rainfall events. We estimate a hedonic property model to determine the loss in house prices from the wildfire and postwildfire flooding. While several studies examine the effects of wildfires and flooding on housing prices separately, to our knowledge, no study has determined the effects of postwildfire flooding in a fire‐adapted watershed. Most hedonic property models estimating impacts of wildfire or flooding use regression analysis to predict impacts. We also contribute to the hedonic property model literature by using nonparametric matching techniques. We find a negative and statistically significant average treatment effect of wildfire and post‐wildfire flooding. The treatment effect, however, differs relative to distance to wildfire perimeter and distance to flood zones. For example, houses located within 5 km of the Schultz Fire perimeter have an estimated 31% loss, while houses within 20 km have an estimated 6% loss. In addition, prices for houses located within 100 m of the 5‐year flood drop by 10% after the flood, whereas prices for houses within 2 km drop by 5%. Our results indicate that careful consideration of the impacts of both wildfire and postwildfire flooding is essential for understanding the net benefits of forested watershed restoration. Plain Language Summary: Wildfires are increasing in severity and frequency, resulting in significant economic losses from both the wildfire event and postwildfire flooding. The Schultz Fire burned 6,100 ha on the steep slopes of San Francisco Mountain near Flagstaff, AZ, USA in 2010. Within a month of the wildfire, summer monsoon rains created flooding and debris flows 1–2 orders of magnitude greater than prewildfire rainfall events. Our work contributes to the current hedonic property literature in two ways. First, to our knowledge, no other research uses changes in house prices to estimate impacts of postwildfire flooding. Second, we apply a unique, rarely used statistical method. We find that house prices decrease postwildfire and flood, indicating that careful consideration of the impacts of both wildfire and postwildfire flooding is essential for understanding the net benefits of forested watershed restoration. Key Points: Wildfires are increasing in severity and frequency, causing changes in landscapes and catastrophic postwildfire floodingWe use a matching approach to estimate the impact of wildfire and post‐wildfire flooding on house prices, including flood risk covariatesHouse prices decrease postwildfire and flood [ABSTRACT FROM AUTHOR]

The phenotypic and genotypic diversity of natural populations of Lotus corniculatus from three locations in northern Greece was investigated. The collection locations were about 100-140 km apart at altitudes ranging from 50 to 900 m and therefore differed in bioclimatic conditions. The collected plants were transplanted and maintained under the same conditions before their phenotypic and genetic assessment. Plants from high altitudes differed from the low- or moderate-altitude plants in terms of leaf characteristics (smaller leaf area: 1.1 cm2 compared to 1.5 cm2 from the low and moderate altitudes) and internode length (shorter internodes: 2.7 cm compared to 3.2 and 13.1 cm from the low and moderate altitudes respectively). At the genetic level, application of the Inter-Specific Simple Sequence Repeats ( ISSR) molecular markers led to distinct placement of the three populations into different clades of a dendrogram, thus revealing regional diversity. The phytogeographic distinction was also supported by principal components analysis. The results showed that even though phenotypic characters could be close, or even indistinguishable, as in the case of plants from the low and middle altitudes, the genetic background could be different. Therefore, assessment of the natural diversity of L. corniculatus requires a combined and integrative approach involving morphological description and molecular characterization. The natural populations of L. corniculatus constitute valuable germplasm for the development of improved and adapted cultivars. [ABSTRACT FROM AUTHOR]

Aims /Introduction Gestational diabetes mellitus ( GDM) is defined as 'carbohydrate intolerance of varying degrees of severity with onset or first recognition during pregnancy,' and is associated with increased fetal and maternal risks. The aims of the present study were to investigate the prevalence of GDM in Scotland over 32 years (1981-2012), and using the data from 2012, to assess how GDM related to maternal body mass index, maternal age, parity, smoking, Scottish Index of Multiple Deprivation, infant gender and macrosomia status. Materials and Methods GDM prevalence along with anthropometric, obstetric and demographic data were collected on a total of 1,891,097 women with a delivery episode between 1 January 1981 and 31 December 2012 using data extracted from the Scottish Morbidity Record 02. Univariate and multivariate logistic regression analysis was undertaken to investigate their association with GDM. Results A ninefold increase in GDM prevalence was observed from 1981 to 2012 ( P < 0.001). GDM prevalence in 2012 was 1.9%. Maternal body mass index, age, parity status, Scottish index of multiple deprivation and fetal macrosomia were positively associated with GDM. Reported smoking status at booking was inversely associated with GDM. Multivariable analysis showed that fetal macrosomia was not associated with GDM status. Conclusions The present study confirmed that the reporting of GDM is low in Scotland, and that GDM is associated with maternal body mass index, maternal age, multiparity and social deprivation. GDM was negatively associated with smoking and requires further investigation. The lack of association between GDM and macrosomia (following multivariate analysis) might reflect the screening processes undertaken in Scotland. [ABSTRACT FROM AUTHOR]

The recharge location for many springs is unknown because they can be sourced from proximal, shallow, atmospheric sources or long-traveled, deep, regional aquifers. The stable isotope ( 18O and 2H) geochemistry of springs water can provide cost-effective indications of relative flow path distance without the expense of drilling boreholes, conducting geophysical studies, or building groundwater flow models. Locally sourced springs generally have an isotopic signature similar to local precipitation for that region and elevation. Springs with a very different isotopic composition than local meteoric inputs likely have non-local recharge, representing a regional source. We tested this local vs. regional flow derived hypothesis with data from a new, large springs isotopic database from studies across Western North America in Arizona, Nevada, and Alberta. The combination of location-specific precipitation data with stable isotopic groundwater data provides an effective method for flow path determination at springs. We found springs in Arizona issue from a mix of regional and local recharge sources. These springs have a weak elevation trend across 1588 m of elevation where higher elevation springs are only slightly more depleted than low elevation springs with a δ18O variation of 5.9‰. Springs sampled in Nevada showed a strong elevation-isotope relationship with high-elevation sites discharging depleted waters and lower elevation springs issuing enriched waters; only a 2.6‰ difference exists in 18O values over an elevation range of more than 1500 m. Alberta's springs are mostly sourced from local flow systems and show a moderate elevation trend of 1200 m, but the largest range in δ18O, 7.1‰. [ABSTRACT FROM AUTHOR]

The article discusses how wildfire and climate change are interacting to drive change in vegetation and reduce quality and quantity of water and mentions that the forest restoration helps to mitigate negative outcomes.

Background The Improving Access to Psychological Therapies (IAPT) service was established to address common mental health problems among the English population in a timely manner in order to counter the social and economic disadvantage accompanying such difficulties. Using the concept of candidacy, we examined how the legitimacy of claims by people with intellectual disabilities to use this service is facilitated or impeded. Method We used a sequential mixed methods design. We completed 21 interviews with a range of stakeholders, including people with intellectual disabilities and their carers. Themes from the interviews were used to design an online survey questionnaire that was returned by 452 staff from IAPT and specialist intellectual disability services. Results Using the candidacy framework, we noted that eligibility and access to IAPT were achieved through dynamic and iterative processes of negotiation involving people with intellectual disabilities and their supporters on one side and IAPT staff and service structures on the other. Barriers and facilitators were apparent throughout the seven dimensions of candidacy (identification, navigation, permeability of services, appearances, adjudications, offers and resistance and operating conditions) and were linked to discourses relating to the character and purpose of IAPT and specialist intellectual disability services. Conclusions Opportunities exist for some people with intellectual disabilities to assert their candidacy for IAPT input, although there are barriers at individual, professional, organisational and structural levels. More attention needs to be paid to how principles of inclusiveness are operationalised within IAPT teams and to the mental health facilitation role of specialist intellectual disability staff. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Opportunities for unlocking the potential of genomics for African trees."

Evapotranspiration (ET) comprises a major portion of the water budget in forests, yet few studies have measured or estimated ET in semi-arid, high-elevation ponderosa pine forests of the south-western USA or have investigated the capacity of models to predict ET in disturbed forests. We measured actual ET with the eddy covariance (eddy) method over 4 years in three ponderosa pine forests near Flagstaff, Arizona, that differ in disturbance history (undisturbed control, wildfire burned, and restoration thinning) and compared these measurements (415-510 mm year−1 on average) with actual ET estimated from five meteorological models [Penman-Monteith (P-M), P-M with dynamic control of stomatal resistance (P-M-d), Priestley-Taylor (P-T), McNaughton-Black (M-B), and Shuttleworth-Wallace (S-W)] and from the Moderate Resolution Imaging Spectroradiometer (MODIS) ET product. The meteorological models with constant stomatal resistance (P-M, M-B, and S-W) provided the most accurate estimates of annual eddy ET (average percent differences ranged between 11 and −14%), but their accuracy varied across sites. The P-M-d consistently underpredicted ET at all sites. The more simplistic P-T model performed well at the control site (18% overprediction) but strongly overpredicted annual eddy ET at the restoration sites (92%) and underpredicted at the fire site (−26%). The MODIS ET underpredicted annual eddy ET at all sites by at least 51% primarily because of underestimation of leaf area index. Overall, we conclude that with accurate parameterization, micrometeorological models can predict ET within 30% in forests of the south-western USA and that remote sensing-based ET estimates need to be improved through use of higher resolution products. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

We studied the role of ecological and anthropogenic impact gradients on ecosystem structure and composition of 56 freshwater springs among mountain, foothills, and prairie ecoregions in southern Alberta, Canada. A random stratified site selection from 2008 to 2012 was based on representation of characteristic springs types across elevation, ecoregions, and land use histories. Springs emergence varied over geomorphic contexts and was dominated by hillslope (28), helocrene (marsh, 13), and rheocrene (stream channel, seven) types, with fewer limnocrene (pool, four), cave (two), gushet (one), and hanging garden (one) springs. Among these springs, specific conductance of non-geothermal springs water was negatively related to elevation and groundwater temperature ( R2 = 0.343 and 0.336 respectively). Plant species richness was positively related to habitat area ( R2 = 0.328) and weakly to geomorphic diversity ( R2 = 0.135) and total alkalinity and specific conductance ( R2 < 0.181). We detected at least 444 higher native plant taxa on only 3.82 ha of springs habitat, equalling 25% of Alberta's flora on <0.001% of the provincial land area. Non-native plant species density was positively related to that of native plants ( R2 = 0.36). Human impacts on springs included livestock production and domestic water supplies, while beaver and other wildlife commonly influenced ecosystem function on protected lands. We conclude that the springs of Alberta are ecologically important but are understudied and inadequately protected, especially with increasing demand for groundwater as a result of extensive allocation and use of surface water in southern Alberta. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The purpose of this study was to develop an interpretive groundwater-flow model to assess the impacts that planned forest restoration treatments and anticipated climate change will have on large regional, deep (>400 m), semi-arid aquifers. Simulations were conducted to examine how tree basal area reductions impact groundwater recharge from historic conditions to 2099. Novel spatial analyses were conducted to determine areas and rates of potential increases in groundwater recharge. Changes in recharge were applied to the model by identifying zones of basal area reduction from planned forest restoration treatments and applying recharge-change factors to these zones. Over a 10-year period of forest restoration treatment, a 2.8% increase in recharge to one adjacent groundwater basin (the Verde Valley sub-basin) was estimated, compared to conditions that existed from 2000 to 2005. However, this increase in recharge was assumed to quickly decline after treatment due to regrowth of vegetation and forest underbrush and their associated increased evapotranspiration. Furthermore, simulated increases in groundwater recharge were masked by decreases in water levels, stream baseflow, and groundwater storage resulting from surface water diversions and groundwater pumping. These results indicate that there is an imbalance between water supply and demand in this regional, semi-arid aquifer. Current water management practices may not be sustainable into the far future and comprehensive action should be taken to minimize this water budget imbalance. [ABSTRACT FROM AUTHOR]

The article focuses on rejection of the names Aloe perfoliata, Aloe obscura, Aloe picta and Aloe perfoliata including Aloe perfoliata being the first name under Aloe L. that is being listed by botanist Carl Linnaeus, use of A. perfoliata as being an old name for A. mitriformis if not rejected.

Declining forest health, climate change, and development threaten the sustainability of water supplies in the western United States. While forest restoration may buffer threats to watershed services, funding shortfalls for landscape-scale restoration efforts limit management action. The hydrologic response and reduction in risk to watersheds following forest restoration treatments could create significant nonmarket benefits for downstream water users. Historic experimental watershed studies indicate a significant and positive response from forest thinning by a reallocation of water from evapotranspiration to surface-water yield. In this study, we estimate the willingness to pay (WTP) for improved watershed services for one group of downstream users, irrigators, following forest restoration activities. We find a positive and statistically significant WTP within our sample of $183.50 per household, at an aggregated benefit of more than $400,000 annually for 2181 irrigators. Our benefit estimate provides evidence that downstream irrigators may be willing to invest in landscape-scale forest restoration to maintain watershed services. [ABSTRACT FROM AUTHOR]

Production and nutritive value of forage in silvopastural systems can be improved by introducing shade- tolerant grass and legume species in appropriate mixtures. The management of these systems can present a challenge regarding the selection of the proper grass and legume species as well as the maintenance of the optimum balance between the two species in the grass-legume stand. The objectives of the present study were to evaluate the performance of pure stands and mixtures (75:25, 50:50, 25:75) of Dactylis glomerata:Trifolium subterraneum under full sun, 60% shade and 90% shade. Dry matter production of D. glomerata was not affected by shading, while that of T. subterraneum was drastically reduced. Shading increased the crude protein (CP) and acid detergent lignin content, but did not affect the acid detergent fibre and neutral detergent fibre content. The dry matter production of the 75:25 and 25:75 mixtures was higher compared to the one of the 50:50 mixture, while the CP content of the 75:25 mixture was the highest under moderate shading. However, relative yield, aggressivity index and competitive balance index indicated higher competitive ability for D. glomerata compared with T. subterraneum especially under shade. Therefore, the 25:75 mixture is suggested as the most suitable under moderate shade (60%), to perpetuate the stand and avoid the frequent re-sowing of T. subterraneum. [ABSTRACT FROM AUTHOR]

The arguments towards resolving the Acacia nomenclatural controversy put forth by Thiele & al. (2011) are reviewed and rebutted. We argue that a truly pragmatic and, moreover, defensible and equitable alternative to accepting the retypification of Acacia Mill. with a conserved type would be to have the 2006 International Code of Botanical Nomenclature, excluding this retypification, serve as the basis for discussions at the Nomenclature Section of the Melbourne International Botanical Congress in 2011. We, and a large component of the international taxonomic community, and beyond, remain convinced that the minority rule voting procedure used at Vienna on Acacia was inappropriate, resulting in animosity that will without any doubt linger until this situation is rectified. Such a minority rule procedure has never in the history of Nomenclature Sections been implemented before. Exclusion of the Acacia retypification can be achieved through a democratic process by objecting to its inclusion when the printed (2006) Code comes up for adoption at the start of the Nomenclature Section. This is perfectly within the established process that has been used in past Section meetings. The integrity of the Code will suffer permanent damage if the retypification of Acacia Mill. with a conserved type is not removed from the ICBN, especially as it ended up there through a minority decision. [ABSTRACT FROM AUTHOR]

This paper briefly reports on the developments surrounding the Acacia name conservation controversy since the Nomenclature Section meeting at the Seventeenth International Botanical Congress at Vienna in 2005. Actions taken at Vienna led to the listing of Acacia Mill. with a conserved type in Appendix lii (p. 286) of the current printed version of the International code of botanical nomenclature. While decisions taken at Nomenclature Sections generally tend to resolve nomenclatural disputes, the actions taken in Vienna with regard to Acacia-i.e., treating the proposal to conserve the name Acacia with a conserved type as approved even though the majority of the votes cast were opposed to the proposal-has only resulted in increased controversy. Today, the Acacia listing in the Code continues to be met with considerable resistance from the global plant taxonomic community and beyond. We believe the "minority rule" approach used in Vienna was contrary to the procedural rules established in Vienna. As a result, an objection to the acceptance of the Vienna Code as currently printed with the Acacia listing will be raised at the Nomenclature Section meeting during the Eighteenth International Botanical Congress in Melbourne in 2011. A procedure is outlined for handling this objection that we hope will allow the botanical community to finally resolve this matter. [ABSTRACT FROM AUTHOR]

Nematodes play an important role in ecosystem processes, yet the relevance of nematode species diversity to ecology is unknown. Because nematode identification of all individuals at the species level using standard techniques is difficult and time-consuming, nematode communities are not resolved down to the species level, leaving ecological analysis ambiguous. We assessed the suitability of massively parallel sequencing for analysis of nematode diversity from metagenomic samples. We set up four artificial metagenomic samples involving 41 diverse reference nematodes in known abundances. Two samples came from pooling polymerase chain reaction products amplified from single nematode species. Two additional metagenomic samples consisted of amplified products of DNA extracted from pooled nematode species. Amplified products involved two rapidly evolving ~400-bp sections coding for the small and large subunit of rRNA. The total number of reads ranged from 4159 to 14771 per metagenomic sample. Of these, 82% were > 199 bp in length. Among the reads > 199 bp, 86% matched the referenced species with less than three nucleotide differences from a reference sequence. Although neither rDNA section recovered all nematode species, the use of both loci improved the detection level of nematode species from 90 to 97%. Overall, results support the suitability of massively parallel sequencing for identification of nematodes. In contrast, the frequency of reads representing individual species did not correlate with the number of individuals in the metagenomic samples, suggesting that further methodological work is necessary before it will be justified for inferring the relative abundances of species within a nematode community. [ABSTRACT FROM AUTHOR]

The genetic manipulation of mosquito vectors is an alternative strategy in the fight against malaria. It was previously shown that bee venom phospholipase A2 (PLA2) inhibits ookinete invasion of the mosquito midgut although mosquito fitness was reduced. To maintain the PLA2 blocking ability without compromising mosquito biology, we mutated the protein-coding sequence to inactivate the enzyme while maintaining the protein's structure. DNA encoding the mutated PLA2 (mPLA2) was placed downstream of a mosquito midgut-specific promoter ( Anopheles gambiae peritrophin protein 1 promoter, AgPer1) and this construct used to transform Aedes fluviatilis mosquitoes. Four different transgenic lines were obtained and characterized and all lines significantly inhibited Plasmodium gallinaceum oocyst development (up to 68% fewer oocysts). No fitness cost was observed when this mosquito species expressed the mPLA2. [ABSTRACT FROM AUTHOR]

Normal migration of the gonadotrophin-releasing hormone (GnRH) neurones during early development, from the olfactory region to the hypothalamus, is crucial for reproductive development in all vertebrates. The establishment of the GnRH system includes tangential migration of GnRH perikarya as well as extension of GnRH fibres to various areas of the central nervous system (CNS). The exact spatio-temporal nature of this process, as well as the factors governing it, are not fully understood. We studied the development of the GnRH system and the effects of GnRH knockdown using a newly developed GnRH3:EGFP transgenic zebrafish line. We found that enhanced green fluorescent protein is specifically and robustly expressed in GnRH3 neurones and fibres. GnRH3 fibres in zebrafish began to extend as early as 26 h post-fertilisation and by 4–5 days post-fertilisation had developed into an extensive network reaching the optic tract, telencephalon, hypothalamus, midbrain tegmentum and hindbrain. GnRH3 fibres also innervated the retina and projected into the trunk via the spinal cord. GnRH3 perikarya were observed migrating along their own fibres from the olfactory region to the preoptic area (POA) via the terminal nerve ganglion and the ventral telencephalon. GnRH3 cells were also observed in the trigeminal ganglion. The establishment of the GnRH3 fibre network was disrupted by morpholino-modified antisense oligonucleotides directed against GnRH3 causing abnormal fibre development and pathfinding, as well as anomalous GnRH3 perikarya localisation. These findings support the hypothesis that GnRH3 neurones migrate from the olfactory region to the POA and caudal hypothalamus. Novel data regarding the early development of the GnRH3 fibre network in the CNS and beyond are described. Moreover we show, in vivo, that GnRH3 is an important factor regulating GnRH3 fibre pathfinding and neurone localisation in an autocrine fashion. [ABSTRACT FROM AUTHOR]

The author reflects on evolutionary versus phylogenetic approaches concerning plant classification. He claims that evolutionary classification is based on the evolution and phylogeny of organisms. He mentions that phylogenetic approach is an ordering system in which the branches of a cladogram are positioned with reference on the principle of holophyly. An overview of observations that defend paraphyletic groups from the point-of-view of an end-user of plant classifications is presented.

The ontogeny of gonadotropin-releasing hormone (GnRH) mRNA-producing neurons was studied in developing hybrid striped bass (white bass Morone chrysops female × striped bass Morone saxatilis male), 1–55 days post-fertilization (dpf), by whole-mount in situ hybridization. Neurons that produce salmon (s) GnRH were first detected at 32 h post-fertilization in the olfactory placodes. These neurons migrated posteriorly during development and reached their final position at the olfactory bulbs-telencephalon boundary, possibly the terminal nerve ganglion (TNg) by 11 dpf. First signal of chicken (c) GnRH-II neurons appeared in the midbrain 2 dpf and remained there throughout development. A signal of seabream (sb) GnRH mRNA was first detected at 21 dpf in the preoptic area (POA) and as a bilateral continuum along the ventral telencephalon at 32–55 dpf. The expression of all three forms of GnRH increased throughout development. These results suggest that cGnRH-II neurons originate in the mid-brain, and that sGnRH neurons originate in the olfactory placodes and migrate caudally to the TNg. Neurons that express sbGnRH seem to originate at the preoptic area and then to migrate anteriorly along the ventral telencephalon. An olfactory placodal origin of these neurons, however, cannot be ruled out. [ABSTRACT FROM AUTHOR]

Springs along the south rim of the Grand Canyon, Arizona, are important ecological and cultural resources in Grand Canyon National Park and are discharge points for regional and local aquifers of the Coconino Plateau. This study evaluated the applicability of electrical resistance (ER) sensors for measuring diffuse, low-stage (<1.0 cm) intermittent and ephemeral flow in the steep, rocky spring-fed tributaries of the south rim. ER sensors were used to conduct a baseline survey of spring flow timing at eight sites in three spring-fed tributaries in Grand Canyon. Sensors were attached to a nearly vertical rock wall at a spring outlet and were installed in alluvial and bedrock channels. Spring flow timing data inferred by the ER sensors were consistent with observations during site visits, with flow events recorded with collocated streamflow gauging stations and with local precipitation gauges. ER sensors were able to distinguish the presence of flow along nearly vertical rock surfaces with flow depths between 0.3 and 1.0 cm. Laboratory experiments confirmed the ability of the sensors to monitor the timing of diffuse flow on impervious surfaces. A comparison of flow patterns along the stream reaches and at springs identified the timing and location of perennial and intermittent flow, and periods of increased evapotranspiration. [ABSTRACT FROM AUTHOR]

One of the largest and rarest Bebb willow ( Salix bebbiana) communities in the United States occurs at Hart Prairie, Arizona. Low recruitment of the willow over the past several decades has been linked to inadequate soil water content for seed germination and seedling establishment. We tested a hypothesis that a prescribed burn would reduce biomass of and evapotranspiration by herbaceous plants, thereby increasing soil water content. Three treatments (unburned control, early-growing season burned, late-growing season burned) were applied in year 2001 to replicated plots in fern- and grass-dominated herbaceous communities. Soil water content (0–30 cm) was measured weekly in plots during the 2001, 2002, and 2003 growing seasons. Both early- and late-season burning reduced herbaceous biomass in the fern-dominated community in 2002 and 2003 and reduced biomass in the grass-dominated community in 2002 but not in 2003. Soil water content increased for approximately four weeks in 2001 following the early-season burn, but the early-season and late-season burns reduced soil water content in both communities over much of the 2002 and 2003 growing seasons. Thus, early-season burning may benefit willow seed germination by increasing soil water content immediately following burning but be detrimental to germination in the second and third growing seasons after burning because of drier soil. Large temporal variation in the effect of prescribed burning on soil water content will complicate the use of fire as a restoration tool to manage soil water available for threatened plants such as Bebb willow and for recharge of groundwater. [ABSTRACT FROM AUTHOR]

Gymnosporia (Wight & Am.) Hook. f. (Celastraceae) is an Old World genus of about 99 species and 19 infra-specific taxa. A historical review of the genus and its conserved status are given. Sectional subdivision of Gymnosporia into eight sections is based mainly on characters from fruit morphology and leaf anatomy. Taxonomically useful characters at section level include: presence or absence of leaf and fruit indumentum, number of valves in the fruit, aril colour and the degree to which it covers the seed. Diagnostic leaf anatomical characters are epidermis cell size, presence or absence of a hypodermis, uni- or multi-seriate epidermis, dorsiventral or isobilateral mesophyll and presence or absence of trichomes or papillae. The newly described sections (species/infraspecific taxa in brackets) are Buxifoliae (29); Capitatae (I); Gymnosporia (6/3); Mossambicenses (11/4); VaccinifoIiae (1/2); Pubescentes (I); Putterlickioides (1/2) and Tenuispinae (49/8). A key to the sections and a list of species in each section are provided. Morphological as well as leaf anatomical characters to assist in the identification of sections are tabulated. Eleven new name combinations, three new ranks and two new names are proposed. [ABSTRACT FROM AUTHOR]

Hart Prairie, Arizona, has the largest Bebb willow ( Salix bebbiana) community in the United States; however, greater than 95% of willows are older than 80 years and regeneration by seed is not occurring. This study examined the evapotranspiration of two herbaceous communities that dominate the Hart Prairie watershed: (1) a mixture of bracken fern ( Pteridium aquilinum) and graminoids and (2) dominantly graminoids. Transpiration during premonsoon and postmonsoon dry periods of 2000, 2001, and 2002 was estimated for each community by the difference in volumetric soil-water content (0-30 cm soil depth) between replicated plots that were clipped of all vegetation and control, unclipped plots. Transpiration rates estimated under conditions of minimal soil drainage varied between 0.63 and 2.4 mm/d for the fern-graminoid community and 0.57 and 1.1 mm/d for the graminoid community over the study. The fern-graminoid community produced more biomass than the graminoid community in all years, but generally had lower transpiration rates. Severe drought in year 2002 reduced growth and transpiration of the fern-graminoid community more than the graminoid community. Evaporation rates were estimated by temporal changes in soil-water content in clipped plots during dry periods, and were 54 to 474% of transpiration rates estimated under conditions of minimal soil drainage because of the dry and windy conditions that occur at the study site. Based on this study and a study of transpiration of scattered trees invading the meadow, transpiration by the herbaceous understory was higher than transpiration by trees during similar seasons. [ABSTRACT FROM AUTHOR]

An improved knowledge of iron biogeochemistry is needed to better understand key controls on the functioning of high-nitrate low-chlorophyll (HNLC) oceanic regions. Iron budgets for HNLC waters have been constructed using data from disparate sources ranging from laboratory algal cultures to ocean physics. In summer 2003 we conducted FeCycle, a 10-day mesoscale tracer release in HNLC waters SE of New Zealand, and measured concurrently all sources (with the exception of aerosol deposition) to, sinks of iron from, and rates of iron recycling within, the surface mixed layer. A pelagic iron budget (timescale of days) indicated that oceanic supply terms (lateral advection and vertical diffusion) were relatively small compared to the main sink (downward particulate export). Remote sensing and terrestrial monitoring reveal 13 dust or wildfire events in Australia, prior to and during FeCycle, one of which may have deposited iron at the study location. However, iron deposition rates cannot be derived from such observations, illustrating the difficulties in closing iron budgets without quantification of episodic atmospheric supply. Despite the threefold uncertainties reported for rates of aerosol deposition (Duce et al., 1991), published atmospheric iron supply for the New Zealand region is ∼50-fold (i.e., 7- to 150-fold) greater than the oceanic iron supply measured in our budget, and thus was comparable (i.e., a third to threefold) to our estimates of downward export of particulate iron. During FeCycle, the fluxes due to short term (hours) biological iron uptake and regeneration were indicative of rapid recycling and were tenfold greater than for new iron (i.e. estimated atmospheric and measured oceanic supply), giving an "fe" ratio (uptake of new iron/uptake of new + regenerated iron) of 0.17 (i.e., a range of 0.06 to 0.51 due to uncertainties on aerosol iron supply), and an "Fe" ratio (biogenic Fe export/uptake of new + regenerated iron) of 0.09 (i.e., 0.03 to 0.24). [ABSTRACT FROM AUTHOR]

TheAnopheles gambiaeadult peritrophic matrix protein 1 (AgAper1) regulatory elements were used to drive the expression of phospholipase A2 (PLA2), a protein known to disrupt malaria parasite development in mosquitoes. TheseAgAper1regulatory elements were sufficient to promote the accumulation of PLA2 in midgut epithelial cells before a blood meal and its release into the lumen upon blood ingestion.Plasmodium bergheioocyst formation was reduced by∼80% (74–91% range) in transgenic mosquitoes. Blood-seeking behaviour and survival ofAgAper1-PLA2 transgenic mosquitoes were comparable to sibling wild-type mosquitoes, while fertility was substantially lower. Ultrastructural studies suggest that decreased fitness is a consequence of internal damage to midgut epithelial cells. [ABSTRACT FROM AUTHOR]

The article discusses the environmental aspects of a controlled flood from the Glen Canyon Dam in Colorado into the Colorado River. It states that impact of river restoration through controlled flood on aquatic and terrestrial ecosystems, and mentions that the flood restored sandbars throughout the river corridor. It notes translocation of a number of endangered Kanab ambersnail, and cites impact of the flood on ethnobotanical resources.

The taxonomy, distribution and cultivation requirements of Crassula tetragona L. subsp. acutifolia (Lam.) Tölken (Crassulaceae), a common but inconspicuous miniature and mat‐forming succulent from the Eastern Cape Province of South Africa, are discussed and a full description of the subspecies is provided. [ABSTRACT FROM AUTHOR]

Presents information on a study which determined the temporal and spatial variability of the hydraulic conductivity of reattachment bar aquifers in the Grand Canyon of the Colorado River. Methods used; Results; Implications for nutrient spiraling and backwater rejuvenation.

The taxonomy, distribution and cultivation requirements of Gasteria baylissiana Rauh (Aloaceae), a rare miniature succulent from the Eastern Cape Province of South Africa, are discussed. Notes on the history and conservation status of this popular collector's item are included and a full description of the species is provided, accompanied by a water-colour illustration. [ABSTRACT FROM AUTHOR]