Two-In-One: A Design Space for Mapping Unimanual Input into Bimanual Interactions in VR for Users with Limited Movement

Virtual Reality (VR) applications often require users to perform actions with two hands when performing tasks and interacting with objects in virtual environments. Although bimanual interactions in VR can resemble real-world interactions—thus increasing realism and improving immersion—they can also pose significant accessibility challenges to people with limited mobility, such as for people who have full use of only one hand. An opportunity exists to create accessible techniques that take advantage of users’ abilities, but designers currently lack structured tools to consider alternative approaches. To begin filling this gap, we propose Two-in-One, a design space that facilitates the creation of accessible methods for bimanual interactions in VR from unimanual input. Our design space comprises two dimensions, bimanual interactions and computer assistance, and we provide a detailed examination of issues to consider when creating new unimanual input techniques that map to bimanual interactions in VR. We used our design space to create three interaction techniques that we subsequently implemented for a subset of bimanual interactions and received user feedback through a video elicitation study with 17 people with limited mobility. Our findings explore complex tradeoffs associated with autonomy and agency and highlight the need for additional settings and methods to make VR accessible to people with limited mobility.

Ten facts about land systems for sustainability

Land use is central to addressing sustainability issues, including biodiversity conservation, climate change, food security, poverty alleviation, and sustainable energy. In this paper, we synthesize knowledge accumulated in land system science, the integrated study of terrestrial social-ecological systems, into 10 hard truths that have strong, general, empirical support. These facts help to explain the challenges of achieving sustainability in land use and thus also point toward solutions. The 10 facts are as follows: 1) Meanings and values of land are socially constructed and contested; 2) land systems exhibit complex behaviors with abrupt, hard-to-predict changes; 3) irreversible changes and path dependence are common features of land systems; 4) some land uses have a small footprint but very large impacts; 5) drivers and impacts of land-use change are globally interconnected and spill over to distant locations; 6) humanity lives on a used planet where all land provides benefits to societies; 7) land-use change usually entails trade-offs between different benefits-"win-wins" are thus rare; 8) land tenure and land-use claims are often unclear, overlapping, and contested; 9) the benefits and burdens from land are unequally distributed; and 10) land users have multiple, sometimes conflicting, ideas of what social and environmental justice entails. The facts have implications for governance, but do not provide fixed answers. Instead they constitute a set of core principles which can guide scientists, policy makers, and practitioners toward meeting sustainability challenges in land use.

Invited review: Intergovernmental Panel on Climate Change, agriculture, and food-A case of shifting cultivation and history

Since 1990, the Intergovernmental Panel on Climate Change (IPCC) has produced five Assessment Reports (ARs), in which agriculture as the production of food for humans via crops and livestock have featured in one form or another. A constructed database of the ca. 2,100 cited experiments and simulations in the five ARs was analyzed with respect to impacts on yields via crop type, region, and whether adaptation was included. Quantitative data on impacts and adaptation in livestock farming have been extremely scarce in the ARs. The main conclusions from impact and adaptation are that crop yields will decline, but that responses have large statistical variation. Mitigation assessments in the ARs have used both bottom-up and top-down methods but need better to link emissions and their mitigation with food production and security. Relevant policy options have become broader in later ARs and included more of the social and nonproduction aspects of food security. Our overall conclusion is that agriculture and food security, which are two of the most central, critical, and imminent issues in climate change, have been dealt with an unfocussed and inconsistent manner between the IPCC five ARs. This is partly a result of not only agriculture spanning two IPCC working groups but also the very strong focus on projections from computer crop simulation modeling. For the future, we suggest a need to examine interactions between themes such as crop resource use efficiencies and to include all production and nonproduction aspects of food security in future roles for integrated assessment models.

Effects and relationships of grazing intensity on multiple ecosystem services in the Inner Mongolian steppe

Grassland ecosystems are one of the most important terrestrial ecosystems in the world, producing essential both goods and ecosystem services (ES) for human beings. The Inner Mongolian steppe is a major grassland ecosystem in Northern China, covering 13.5% of the northern Chinese grassland area, and playing important ecological roles for the adjacent region of the capital Beijing-Tianjin-Hebei. Quantification of grassland ES under the different utilization patterns is vital for the maintenance of multiple ES and mitigation against ES loss in this region. We made a manipulative experiment with four grazing intensities (grazing exclusion, GE; light grazing intensity, LG; medium grazing intensity, MG; heavy grazing intensity, HG). We then quantified the intensities of eight different grassland ES (1. herbage intake, HT; 2. biodiversity conservation, BI; 3. soil nutrient retention, SN; 4 soil carbon stocks SC; 5. soil erosion prevention, SEP; 6. soil water storage, SWC; 7. potential nutrient recycling, PNC; 8. carbon sequestration from atmosphere. CS) and total ES via a series of field measurements. Pearson coefficients and trade-offs index were used to access the above ES relationships and degree of trade-offs between ES. Grazing intensities significantly (p < 0.05) affected the grassland intensities of 'regulating', 'culture' and 'provisioning' services, but the 'supporting' services. We found three types of relationships (trade-offs, synergy or neutral) have been found in this study. Trade-offs occurred between 'provisioning' and 'regulating' services. Although GE management presented significantly higher intensity of total ES (0.64) than LG (0.52), LG management significantly weakened the trade-offs between 'provisioning' and 'regulating' services (Trade-offs index 0.22) in comparison with GE (Trade-offs index 11.02). Our study suggests, therefore, that LG is the most suitable grassland utilization practice in the Inner Mongolian steppe.

Global wheat production with 1.5 and 2.0°C above pre-industrial warming

Efforts to limit global warming to below 2°C in relation to the pre-industrial level are under way, in accordance with the 2015 Paris Agreement. However, most impact research on agriculture to date has focused on impacts of warming >2°C on mean crop yields, and many previous studies did not focus sufficiently on extreme events and yield interannual variability. Here, with the latest climate scenarios from the Half a degree Additional warming, Prognosis and Projected Impacts (HAPPI) project, we evaluated the impacts of the 2015 Paris Agreement range of global warming (1.5 and 2.0°C warming above the pre-industrial period) on global wheat production and local yield variability. A multi-crop and multi-climate model ensemble over a global network of sites developed by the Agricultural Model Intercomparison and Improvement Project (AgMIP) for Wheat was used to represent major rainfed and irrigated wheat cropping systems. Results show that projected global wheat production will change by -2.3% to 7.0% under the 1.5°C scenario and -2.4% to 10.5% under the 2.0°C scenario, compared to a baseline of 1980-2010, when considering changes in local temperature, rainfall, and global atmospheric CO₂ concentration, but no changes in management or wheat cultivars. The projected impact on wheat production varies spatially; a larger increase is projected for temperate high rainfall regions than for moderate hot low rainfall and irrigated regions. Grain yields in warmer regions are more likely to be reduced than in cooler regions. Despite mostly positive impacts on global average grain yields, the frequency of extremely low yields (bottom 5 percentile of baseline distribution) and yield inter-annual variability will increase under both warming scenarios for some of the hot growing locations, including locations from the second largest global wheat producer-India, which supplies more than 14% of global wheat. The projected global impact of warming <2°C on wheat production is therefore not evenly distributed and will affect regional food security across the globe as well as food prices and trade.

Enspara: Modeling molecular ensembles with scalable data structures and parallel computing

Markov state models (MSMs) are quantitative models of protein dynamics that are useful for uncovering the structural fluctuations that proteins undergo, as well as the mechanisms of these conformational changes. Given the enormity of conformational space, there has been ongoing interest in identifying a small number of states that capture the essential features of a protein. Generally, this is achieved by making assumptions about the properties of relevant features-for example, that the most important features are those that change slowly. An alternative strategy is to keep as many degrees of freedom as possible and subsequently learn from the model which of the features are most important. In these larger models, however, traditional approaches quickly become computationally intractable. In this paper, we present enspara, a library for working with MSMs that provides several novel algorithms and specialized data structures that dramatically improve the scalability of traditional MSM methods. This includes ragged arrays for minimizing memory requirements, message passing interface-parallelized implementations of compute-intensive operations, and a flexible framework for model construction and analysis.

Climate change impact and adaptation for wheat protein

Wheat grain protein concentration is an important determinant of wheat quality for human nutrition that is often overlooked in efforts to improve crop production. We tested and applied a 32-multi-model ensemble to simulate global wheat yield and quality in a changing climate. Potential benefits of elevated atmospheric CO₂ concentration by 2050 on global wheat grain and protein yield are likely to be negated by impacts from rising temperature and changes in rainfall, but with considerable disparities between regions. Grain and protein yields are expected to be lower and more variable in most low-rainfall regions, with nitrogen availability limiting growth stimulus from elevated CO₂ . Introducing genotypes adapted to warmer temperatures (and also considering changes in CO₂ and rainfall) could boost global wheat yield by 7% and protein yield by 2%, but grain protein concentration would be reduced by -1.1 percentage points, representing a relative change of -8.6%. Climate change adaptations that benefit grain yield are not always positive for grain quality, putting additional pressure on global wheat production.

Simulation of Soil Organic Carbon Effects on Long-Term Winter Wheat (Triticum aestivum) Production Under Varying Fertilizer Inputs

Soil organic carbon (SOC) has a vital role to enhance agricultural productivity and for mitigation of climate change. To quantify SOC effects on productivity, process models serve as a robust tool to keep track of multiple plant and soil factors and their interactions affecting SOC dynamics. We used soil-plant-atmospheric model viz. DAISY, to assess effects of SOC on nitrogen (N) supply and plant available water (PAW) under varying N fertilizer rates in winter wheat (Triticum aestivum) in Denmark. The study objective was assessment of SOC effects on winter wheat grain and aboveground biomass accumulation at three SOC levels (low: 0.7% SOC; reference: 1.3% SOC; and high: 2% SOC) with five nitrogen rates (0-200 kg N ha^-1) and PAW at low, reference, and high SOC levels. The three SOC levels had significant effects on grain yields and aboveground biomass accumulation at only 0-100 kg N ha^-1 and the SOC effects decreased with increasing N rates until no effects at 150-200 kg N ha^-1. PAW had significant positive correlation with SOC content, with high SOC retaining higher PAW compared to low and reference SOC. The mean PAW and SOC correlation was given by PAW% = 1.0073 × SOC% + 15.641. For the 0.7-2% SOC range, the PAW increase was small with no significant effects on grain yields and aboveground biomass accumulation. The higher winter wheat grain and aboveground biomass was attributed to higher N supply in N deficient wheat production system. Our study suggested that building SOC enhances agronomic productivity at only 0-100 kg N ha^-1. Maintenance of SOC stock will require regular replenishment of SOC, to compensate for the mineralization process degrading SOC over time. Hence, management can maximize realization of SOC benefits by building up SOC and maintaining N rates in the range 0-100 kg N ha^-1, to reduce the off-farm N losses depending on the environmental zones, land use and the production system.

Baby Steps Text: Feasibility Study of an SMS-Based Tool for Tracking Children's Developmental Progress

To help reach populations of children without consistent Internet access or medical care, we designed and implemented Baby Steps Text, an automated text message-based screening tool. We conducted preliminary user research via storyboarding and prototyping with target populations and then developed a fully functional system. In a one-month deployment study, we evaluated the feasibility of Baby Steps Text with fourteen families. During a one-month study, 13 out of 14 participants were able to learn and use the response structure (yielding 2.88% error rate) and complete a child development screener entirely via text messages. All post-study survey respondents agreed Baby Steps Text was understandable and easy to use, which was also confirmed through post-study interviews. Some survey respondents expressed liking Baby Steps Text because it was easy, quick, convenient to use, and delivered helpful, timely information. Our initial deployment study shows text messaging is a feasible tool for supporting parents in tracking and monitoring their child's development.

Circulating Microvesicles Are Elevated Acutely following Major Burns Injury and Associated with Clinical Severity

Microvesicles are cell-derived signaling particles emerging as important mediators and biomarkers of systemic inflammation, but their production in severe burn injury patients has not been described. In this pilot investigation, we measured circulating microvesicle levels following severe burns, with severe sepsis patients as a comparator group. We hypothesized that levels of circulating vascular cell-derived microvesicles are elevated acutely following burns injury, mirroring clinical severity due to the early onset and prevalence of systemic inflammatory response syndrome (SIRS) in these patients. Blood samples were obtained from patients with moderate to severe thermal injury burns, with severe sepsis, and from healthy volunteers. Circulating microvesicles derived from total leukocytes, granulocytes, monocytes, and endothelial cells were quantified in plasma by flow cytometry. All circulating microvesicle subpopulations were elevated in burns patients on day of admission (day 0) compared to healthy volunteers (leukocyte-microvesicles: 3.5-fold, p = 0.005; granulocyte-microvesicles: 12.8-fold, p<0.0001; monocyte-microvesicles: 20.4-fold, p<0.0001; endothelial- microvesicles: 9.6-fold, p = 0.01), but decreased significantly by day 2. Microvesicle levels were increased with severe sepsis, but less consistently between patients. Leukocyte- and granulocyte-derived microvesicles on day 0 correlated with clinical assessment scores and were higher in burns ICU non-survivors compared to survivors (leukocyte MVs 4.6 fold, p = 0.002; granulocyte MVs 4.8 fold, p = 0.003). Mortality prediction analysis of area under receiver operating characteristic curve was 0.92 (p = 0.01) for total leukocyte microvesicles and 0.85 (p = 0.04) for granulocyte microvesicles. These findings demonstrate, for the first time, acute increases in circulating microvesicles following burns injury in patients and point to their potential role in propagation of sterile SIRS-related pathophysiology.

The toxin biliatresone causes mouse extrahepatic cholangiocyte damage and fibrosis through decreased glutathione and SOX17

Biliary atresia, the most common indication for pediatric liver transplantation, is a fibrotic disease of unknown etiology affecting the extrahepatic bile ducts of newborns. The recently described toxin biliatresone causes lumen obstruction in mouse cholangiocyte spheroids and represents a new model of biliary atresia. The goal of this study was to determine the cellular changes caused by biliatresone in mammalian cells that ultimately lead to biliary atresia and extrahepatic fibrosis. We treated mouse cholangiocytes in three-dimensional (3D) spheroid culture and neonatal extrahepatic duct explants with biliatresone and compounds that regulate glutathione (GSH). We examined the effects of biliatresone on SOX17 levels and determined the effects of Sox17 knockdown on cholangiocytes in 3D culture. We found that biliatresone caused disruption of cholangiocyte apical polarity and loss of monolayer integrity. Spheroids treated with biliatresone had increased permeability as shown by rhodamine efflux within 5 hours compared with untreated spheroids, which retained rhodamine for longer than 12 hours. Neonatal bile duct explants treated with the toxin showed lumen obstruction with increased subepithelial staining for α-smooth muscle actin and collagen, consistent with fibrosis. Biliatresone caused a rapid and transient decrease in GSH, which was both necessary and sufficient to mediate its effects in cholangiocyte spheroid and bile duct explant systems. It also caused a significant decrease in cholangiocyte levels of SOX17, and Sox17 knockdown in cholangiocyte spheroids mimicked the effects of biliatresone.

CONCLUSION

Biliatresone decreases GSH and SOX17 in mouse cholangiocytes. In 3D cell systems, this leads to cholangiocyte monolayer damage and increased permeability; in extrahepatic bile duct explants, it leads to disruption of the extrahepatic biliary tree and subepithelial fibrosis. This mechanism may be important in understanding human biliary atresia. (Hepatology 2016;64:880-893).

Glutathione antioxidant pathway activity and reserve determine toxicity and specificity of the biliary toxin biliatresone in zebrafish

Biliatresone is an electrophilic isoflavone isolated from Dysphania species plants that has been causatively linked to naturally occurring outbreaks of a biliary atresia (BA)-like disease in livestock. Biliatresone has selective toxicity for extrahepatic cholangiocytes (EHCs) in zebrafish larvae. To better understand its mechanism of toxicity, we performed transcriptional profiling of liver cells isolated from zebrafish larvae at the earliest stage of biliatresone-mediated biliary injury, with subsequent comparison of biliary and hepatocyte gene expression profiles. Transcripts encoded by genes involved in redox stress response, particularly those involved in glutathione (GSH) metabolism, were among the most prominently up-regulated in both cholangiocytes and hepatocytes of biliatresone-treated larvae. Consistent with these findings, hepatic GSH was depleted at the onset of biliary injury, and in situ mapping of the hepatic GSH redox potential using a redox-sensitive green fluorescent protein biosensor showed that it was significantly more oxidized in EHCs both before and after treatment with biliatresone. Pharmacological and genetic manipulation of GSH redox homeostasis confirmed the importance of GSH in modulating biliatresone-induced injury given that GSH depletion sensitized both EHCs and the otherwise resistant intrahepatic cholangiocytes to the toxin, whereas replenishing GSH level by N-acetylcysteine administration or activation of nuclear factor erythroid 2-like 2 (Nrf2), a transcriptional regulator of GSH synthesis, inhibited EHC injury.

CONCLUSION

These findings strongly support redox stress as a critical contributing factor in biliatresone-induced cholangiocyte injury, and suggest that variations in intrinsic stress responses underlie the susceptibility profile. Insufficient antioxidant capacity of EHCs may be critical to early pathogenesis of human BA. (Hepatology 2016;64:894-907).

Food and nutritional security requires adequate protein as well as energy, delivered from whole-year crop production

Human food security requires the production of sufficient quantities of both high-quality protein and dietary energy. In a series of case-studies from New Zealand, we show that while production of food ingredients from crops on arable land can meet human dietary energy requirements effectively, requirements for high-quality protein are met more efficiently by animal production from such land. We present a model that can be used to assess dietary energy and quality-corrected protein production from various crop and crop/animal production systems, and demonstrate its utility. We extend our analysis with an accompanying economic analysis of commercially-available, pre-prepared or simply-cooked foods that can be produced from our case-study crop and animal products. We calculate the per-person, per-day cost of both quality-corrected protein and dietary energy as provided in the processed foods. We conclude that mixed dairy/cropping systems provide the greatest quantity of high-quality protein per unit price to the consumer, have the highest food energy production and can support the dietary requirements of the highest number of people, when assessed as all-year-round production systems. Global food and nutritional security will largely be an outcome of national or regional agroeconomies addressing their own food needs. We hope that our model will be used for similar analyses of food production systems in other countries, agroecological zones and economies.

Reactivity of Biliatresone, a Natural Biliary Toxin, with Glutathione, Histamine, and Amino Acids

In our previous work, we identified a natural toxin, biliatresone, from Dysphania glomulifera and D. littoralis, endemic plants associated with outbreaks of biliary atresia in Australian neonatal livestock. Biliatresone is a very rare isoflavonoid with an α-methylene ketone between two phenyls, 1,2-diaryl-2-propenone, along with methylenedioxy, dimethoxyl, and hydroxyl functional groups, that causes extrahepatic biliary toxicity in zebrafish. The toxic core of biliatresone is a methylene in the α-position relative to the ketone of 1,2-diaryl-2-propenone that serves as an electrophilic Michael acceptor. The α-methylene of biliatresone spontaneously conjugated with water and methanol (MeOH), respectively, via Michael addition in a reverse phase high-performance liquid chromatography (RP-HPLC) analysis. We here report the reactivity of biliatresone toward glutathione (GSH), several amino acids, and other thiol- or imidazole-containing biomolecules. LC-MS and HPLC analysis of the conjugation reaction showed the reactivity of biliatresone to be in the order histidine > N-acetyl-d-cysteine (D-NAC) = N-acetyl-l-cysteine (L-NAC) > histamine > glutathione ≥ cysteine ≫ glycine > glutamate > phenylalanine, while serine and adenine had no reactivity due to intramolecular hydrogen bonding in the protic solvents. The reactivity of ethyl vinyl ketone (EVK, 1-penten-3-one), an example of a highly reactive α,ß-unsaturated ketone, toward GSH gave a 6.7-fold lower reaction rate constant than that of biliatresone. The reaction rate constant of synthetic 1,2-diaryl-2-propen-1-one (DP), a core structure of the toxic molecule, was 10-fold and 1.5-fold weaker in potency compared to the reaction rate constants of biliatresone and EVK, respectively. These results demostrated that the methylenedioxy, dimethoxyl, and hydroxyl functional groups of biliatresone contribute to the stronger reactivity of the Michael acceptor α-methylene ketone toward nucleophiles compared to that of DP and EVK.

Identification of a plant isoflavonoid that causes biliary atresia

Biliary atresia (BA) is a rapidly progressive and destructive fibrotic disorder of unknown etiology affecting the extrahepatic biliary tree of neonates. Epidemiological studies suggest that an environmental factor, such as a virus or toxin, is the cause of the disease, although none have been definitively established. Several naturally occurring outbreaks of BA in Australian livestock have been associated with the ingestion of unusual plants by pregnant animals during drought conditions. We used a biliary secretion assay in zebrafish to isolate a previously undescribed isoflavonoid, biliatresone, from Dysphania species implicated in a recent BA outbreak. This compound caused selective destruction of the extrahepatic, but not intrahepatic, biliary system of larval zebrafish. A mutation that enhanced biliatresone toxicity mapped to a region of the zebrafish genome that has conserved synteny with an established human BA susceptibility locus. The toxin also caused loss of cilia in neonatal mouse extrahepatic cholangiocytes in culture and disrupted cell polarity and monolayer integrity in cholangiocyte spheroids. Together, these findings provide direct evidence that BA could be initiated by perinatal exposure to an environmental toxin.

Decoupling of greenhouse gas emissions from global agricultural production: 1970-2050

Since 1970 global agricultural production has more than doubled; contributing ~1/4 of total anthropogenic greenhouse gas (GHG) burden in 2010. Food production must increase to feed our growing demands, but to address climate change, GHG emissions must decrease. Using an identity approach, we estimate and analyse past trends in GHG emission intensities from global agricultural production and land-use change and project potential future emissions. The novel Kaya-Porter identity framework deconstructs the entity of emissions from a mix of multiple sources of GHGs into attributable elements allowing not only a combined analysis of the total level of all emissions jointly with emissions per unit area and emissions per unit product. It also allows us to examine how a change in emissions from a given source contributes to the change in total emissions over time. We show that agricultural production and GHGs have been steadily decoupled over recent decades. Emissions peaked in 1991 at ~12 Pg CO2 -eq. yr(-1) and have not exceeded this since. Since 1970 GHG emissions per unit product have declined by 39% and 44% for crop- and livestock-production, respectively. Except for the energy-use component of farming, emissions from all sources have increased less than agricultural production. Our projected business-as-usual range suggests that emissions may be further decoupled by 20-55% giving absolute agricultural emissions of 8.2-14.5 Pg CO2 -eq. yr(-1) by 2050, significantly lower than many previous estimates that do not allow for decoupling. Beyond this, several additional costcompetitive mitigation measures could reduce emissions further. However, agricultural GHG emissions can only be reduced to a certain level and a simultaneous focus on other parts of the food-system is necessary to increase food security whilst reducing emissions. The identity approach presented here could be used as a methodological framework for more holistic food systems analysis.

An Isoflavone from Leiophyllum buxifolium and Its Antiproliferative Effect

A new C-methylisoflavone, isosideroxylin (1), and a known C-methylflavone, sideroxylin (2), were isolated from the EtOAc extract of the leaves of Leiophyllum buxifolium. The two compounds were evaluated with the sulforhodamine B assay for their antiproliferative effects against ER(-) MDA-MB-231 and ER(+) MCF-7 breast cancer cell lines and the NIH3T3 mouse fibroblast cell line. Isosideroxylin (1) displayed a selective antiproliferative effect against MDA-MB-231 cells.

Biliatresone, a Reactive Natural Toxin from Dysphania glomulifera and D. littoralis: Discovery of the Toxic Moiety 1,2-Diaryl-2-Propenone

We identified a reactive natural toxin, biliatresone, from Dysphania glomulifera and D. littoralis collected in Australia that produces extrahepatic biliary atresia in a zebrafish model. Three additional isoflavonoids, including the known isoflavone betavulgarin, were also isolated. Biliatresone is in the very rare 1,2-diaryl-2-propenone class of isoflavonoids. The α-methylene of the 1,2-diaryl-2-propenone of biliatresone spontaneously reacts via Michael addition in the formation of water and methanol adducts. The lethal dose of biliatresone in a zebrafish assay was 1 μg/mL, while the lethal dose of synthetic 1,2-diaryl-2-propen-1-one was 5 μg/mL, suggesting 1,2-diaryl-2-propenone as the toxic Michael acceptor.

Relationship between C:N/C:O stoichiometry and ecosystem services in managed production systems

Land use and management intensity can influence provision of ecosystem services (ES). We argue that forest/agroforestry production systems are characterized by relatively higher C:O/C:N and ES value compared to arable production systems. Field investigations on C:N/C:O and 15 ES were determined in three diverse production systems: wheat monoculture (C_wheat), a combined food and energy system (CFE) and a beech forest in Denmark. The C:N/C:O ratios were 194.1/1.68, 94.1/1.57 and 59.5/1.45 for beech forest, CFE and C_wheat, respectively. The economic value of the non-marketed ES was also highest in beech forest (US$ 1089 ha^-1 yr^-1) followed by CFE (US$ 800 ha^-1 yr^-1) and C_wheat (US$ 339 ha^-1 yr^-1). The combined economic value was highest in the CFE (US$ 3143 ha^-1 yr^-1) as compared to the C_wheat (US$ 2767 ha^-1 yr^-1) and beech forest (US$ 2365 ha^-1 yr^-1). We argue that C:N/C:O can be used as a proxy of ES, particularly for the non-marketed ES, such as regulating, supporting and cultural services. These ES play a vital role in the sustainable production of food and energy. Therefore, they should be considered in decision making and developing appropriate policy responses for land use management.

Significance and value of non-traded ecosystem services on farmland

Background. Ecosystem services (ES) generated within agricultural landscapes, including field boundaries, are vital for the sustainable supply of food and fibre. However, the value of ES in agriculture has not been quantified experimentally and then extrapolated globally. Methods. We quantified the economic value of two key but contrasting ES (biological control of pests and nitrogen mineralisation) provided by non-traded non-crop species in ten organic and ten conventional arable fields in New Zealand using field experiments. The arable crops grown, same for each organic and conventional pair, were peas (Pisum sativum), beans (Phaseolus vulgaris), barley (Hordeum vulgare), and wheat (Triticum aestivum). Organic systems were chosen as comparators not because they are the only forms of sustainable agriculture, but because they are subject to easily understood standards. Results. We found that organic farming systems depended on fewer external inputs and produced outputs of energy and crop dry matter generally less than but sometimes similar to those of their conventional counterparts. The economic values of the two selected ES were greater for the organic systems in all four crops, ranging from US$ 68-200 ha(-1) yr(-1) for biological control of pests and from US$ 110-425 ha(-1)yr(-1) for N mineralisation in the organic systems versus US$ 0 ha(-1)yr(-1) for biological control of pests and from US$ 60-244 ha(-1)yr(-1) for N mineralisation in the conventional systems. The total economic value (including market and non-market components) was significantly greater in organic systems, ranging from US$ 1750-4536 ha(-1)yr(-1), with US$ 1585-2560 ha(-1)yr(-1) in the conventional systems. The non-market component of the economic value in organic fields was also significantly higher than those in conventional fields. Discussion. To illustrate the potential magnitude of these two ES to temperate farming systems and agricultural landscapes elsewhere, we then extrapolate these experimentally derived figures to the global temperate cropping area of the same arable crops. We found that the extrapolated net value of the these two services provided by non-traded species could exceed the combined current global costs of pesticide and fertiliser inputs, even if utilised on only 10% of the global arable area. This approach strengthens the case for ES-rich agricultural systems, provided by non-traded species to global agriculture.

Novel production of terpenoids in Escherichia coli and activities against breast cancer cell lines

Metabolic engineering of heterologous pathways has allowed the production of therapeutically important compounds in microbial systems. Here, we report the engineering of a monoterpenoid biosynthetic pathway into Escherichia coli. Five genes encoding sequential enzymes for perillyl alcohol biosynthesis from the precursors isopentenyl pyrophosphate (IPP) and dimethylallyl pyrophosphate (DMAPP) were engineered into E. coli. Expression of these genes allowed the production of the intermediate limonene, but the downstream monoterpenoid, perillyl alcohol, was not detected. A new compound was detected but could not be identified based on the data obtained. Only 1.6 μg/ml of the compound was being produced from the engineered E. coli strain, but, when these cultures were fed limonene as a substrate, the production was nearly 250 μg/ml. This unknown compound inhibited the cell proliferation of MCF-7 and MDA-MB-231 breast cancer cells in 48-h treatment experiments. This compound may have potential benefits in breast cancer treatment. This is the first report showing the production of a monoterpenoid in engineered E. coli and its antiproliferative effects in breast cancer cells.

Temperatures and the growth and development of maize and rice: a review

Because of global land surface warming, extreme temperature events are expected to occur more often and more intensely, affecting the growth and development of the major cereal crops in several ways, thus affecting the production component of food security. In this study, we have identified rice and maize crop responses to temperature in different, but consistent, phenological phases and development stages. A literature review and data compilation of around 140 scientific articles have determined the key temperature thresholds and response to extreme temperature effects for rice and maize, complementing an earlier study on wheat. Lethal temperatures and cardinal temperatures, together with error estimates, have been identified for phenological phases and development stages. Following the methodology of previous work, we have collected and statistically analysed temperature thresholds of the three crops for the key physiological processes such as leaf initiation, shoot growth and root growth and for the most susceptible phenological phases such as sowing to emergence, anthesis and grain filling. Our summary shows that cardinal temperatures are conservative between studies and are seemingly well defined in all three crops. Anthesis and ripening are the most sensitive temperature stages in rice as well as in wheat and maize. We call for further experimental studies of the effects of transgressing threshold temperatures so such responses can be included into crop impact and adaptation models.

Deconstructing crop processes and models via identities

This paper is part review and part opinion piece; it has three parts of increasing novelty and speculation in approach. The first presents an overview of how some of the major crop simulation models approach the issue of simulating the responses of crops to changing climatic and weather variables, mainly atmospheric CO2 concentration and increased and/or varying temperatures. It illustrates an important principle in models of a single cause having alternative effects and vice versa. The second part suggests some features, mostly missing in current crop models, that need to be included in the future, focussing on extreme events such as high temperature or extreme drought. The final opinion part is speculative but novel. It describes an approach to deconstruct resource use efficiencies into their constituent identities or elements based on the Kaya-Porter identity, each of which can be examined for responses to climate and climatic change. We give no promise that the final part is 'correct', but we hope it can be a stimulation to thought, hypothesis and experiment, and perhaps a new modelling approach.

Pressor responses to ephedrine are not impaired in dopamine beta-hydroxylase knockout mice

BACKGROUND AND PURPOSE

Ephedrine and amphetamine can cause substantial increases in systemic arterial pressure. However, the role of endogenous noradrenaline release in mediating the pressor response to ephedrine is controversial. Studies using pharmacologic agents to decrease the synthesis, storage, and release of catecholamines have supported both a direct and an indirect mechanism of action for ephedrine. The purpose of the present study was to determine if endogenous noradrenaline release is required for cardiovascular responses to ephedrine and amphetamine using a genetic mouse model.

EXPERIMENTAL APPROACH

Increases in systemic arterial pressure and heart rate in response to ephedrine and amphetamine were investigated and compared in dopamine beta-hydroxylase knockout (Dbh -/-) mice that cannot synthesize noradrenaline. Dbh +/- littermates have normal noradrenaline and adrenaline tissue levels, and served as controls in all experiments.

KEY RESULTS

In Dbh -/- mice the increases in systemic arterial pressure and heart rate in response to i.v. injections of ephedrine were not impaired whereas responses to amphetamine were markedly reduced, when compared with responses in Dbh +/- mice. The pressor response to tyramine was abolished whereas pressor responses to noradrenaline, phenylephrine, dopamine, and angiotensin II were similar in Dbh -/- and Dbh +/- mice.

CONCLUSIONS AND IMPLICATIONS

The present results in Dbh -/- mice provide support for the hypothesis that pressor responses to ephedrine are directly mediated whereas responses to amphetamine are dependent on the release of noradrenaline and suggest that Dbh +/- and Dbh -/- mice are useful for the study of direct and indirect mechanisms.

Asian MODY: are we missing an important diagnosis?

AIMS

Maturity onset diabetes of the young (MODY) is a monogenic form of diabetes where correct diagnosis alters treatment, prognosis and genetic counselling. The first UK survey of childhood MODY identified 20 White, but no Asian children with MODY. We hypothesized that MODY causes diabetes in UK Asians, but is underdiagnosed.

METHODS

Children with dominant family histories of diabetes were recruited. Direct sequencing for mutations in the two most common MODY genes; HNF1A (TCF1) and GCK was performed in autoantibody-negative probands. We also compared MODY testing data for Asian and White cases from the Exeter MODY database, to 2001 UK census data.

RESULTS

We recruited 30 families and identified three Asian families with MODY gene mutations (two HNF1A, one GCK) and three White UK families (two HNF1A, one GCK). Heterozygous MODY phenotypes were similar in Asians and Whites. Only eight (0.5%) of 1369 UK referrals for MODY testing were known to be Asian, but in 2001 Asians represented 4% of the English/Welsh population and have a higher prevalence of diabetes.

CONCLUSIONS

We identified three cases of childhood MODY in UK Asians and demonstrated reduced rates of MODY testing in Asians, which has negative implications for treatment. It is unclear why this is. MODY should be considered in autoantibody-negative Asian diabetes patients lacking evidence of insulin resistance.

Three new diterpenes and the biological activity of different extracts of Jasonia montana

Three new diterpenes, namely jasonin-a (1), jasonin-b (2), and jasonin-c (3) were isolated from the aerial parts of Jasonia montana (Asteraceae). Their structures were elucidated on the basis of spectral data as [(1E)-2-((2S)-1,2,5-trimethylbicyclo[3.2.l]octan-8-yl)vinyl] benzene-3-carboxylic acid (1), [3-((2S, 5S)-1,2, 5-trimethylcycloheptanyl)propyl]benzene-3-carboxylic acid (2), and [(1E)-3-((7R)-1,7-dimethy-4-methylenecycloheptanyl)prop-1-enyl] benzene-3-carboxylic acid (3). In addition, the previously reported 5,7,3'-trihydroxy-3,6,4'-trimethoxy flavone designated as centaureidin (4), was also isolated and characterized from this source. The different extracts of the plant were also screened for hypoglycemic, antidiabetic, and antimicrobial activities, wherein the petroleum ether and ethanolic extracts exhibited hypoglycemic and antidiabetic activity, and the petroleum ether and chloroform extracts showed antimicrobial activity.

Syndromic obesity and diabetes: changes in body composition with age and mutation analysis of ALMS1 in 12 United Kingdom kindreds with Alstrom syndrome

CONTEXT

Alström syndrome (AS) is a monogenic form of infancy-onset obesity and insulin resistance, caused by ALMS1 mutations. The natural history of the insulin resistance is unknown, in particular how this relates to changes in body composition. It is also unclear how ALMS1 mutations relate to the characteristic phenotype.

OBJECTIVES

Our objectives were to characterize body composition and metabolic parameters, to establish ALMS1 mutation spectrum of United Kingdom AS patients, and to determine whether a genotype-phenotype correlation exists.

DESIGN AND PATIENTS

We conducted a cross-sectional cohort study of 12 unrelated subjects with AS. Age-standardized body composition was assessed by anthropometry and dual-energy x-ray absorptiometry and insulin sensitivity by homeostasis model assessment. The exons and intron-exon boundaries of ALMS1 were directly sequenced.

SETTING

The study was performed during the annual Alström Syndrome UK multidisciplinary screening clinic.

RESULTS

AS patients have early-onset obesity, but body mass index, waist circumference, and body fat from dual-energy x-ray absorptiometry were negatively correlated with age (r = -0.37, P = 0.2; r = -0.84, P = 0.002; and r = -0.6, P = 0.05). Despite this, insulin resistance increased, demonstrated by raised fasting insulin and fall in homeostasis model assessment insulin sensitivity with age (r = -0.64, P = 0.02). ALMS1 mutations were identified in 10 of 12 patients, with a potential founder mutation in exon 16 present in five [np 10775del (C); Del3592fs/ter3597]. No genotype-phenotype correlation was observed.

CONCLUSIONS

We identified mutations in ALMS1 in more than 80% of patients with no genotype-phenotype correlation. In AS, severe childhood obesity, waist circumference, and body fat decrease with age, whereas insulin resistance increases. The abdominal obesity, insulin resistance, diabetes, hypertriglyceridemia, and hypertension suggest that AS could represent a monogenic model for the metabolic syndrome.

Endophyte fungal isolates from Podophyllum peltatum produce podophyllotoxin

The lignan podophyllotoxin (1) is highly valued as the precursor to clinically useful anticancer drugs. Substantial drug development of this compound class continues, including potential new use for inflammatory disease. We have isolated two endophyte fungi, both strains of Phialocephala fortinii, from rhizomes of the plant Podophyllum peltatum. The fungi were identified through DNA sequencing and morphology. Both strains of fungi are slow-growing and produce 1 at low but measurable amounts in broth culture. The compound was confirmed through matching HPLC retention times, absorption spectra, and MS data to authentic 1. The yield of 1 has ranged from 0.5 to 189 microg/L in 4 weeks of culture. These fungi have implications for the sustained production of 1 independent of wild populations of the source plants.

Information literacy in biology education: an example from an advanced cell biology course

Information literacy skills are critically important for the undergraduate biology student. The ability to find, understand, evaluate, and use information, whether from the scientific literature or from Web resources, is essential for a good understanding of a topic and for the conduct of research. A project in which students receive information literacy instruction and then proceed to select, update, and write about a current research topic in an upper-level cell biology course is described. Students research the chosen topic using paper and electronic resources, generate a list of relevant articles, prepare abstracts based on papers read, and, finally, prepare a "state-of-the-art" paper on the topic. This approach, which extends over most of one semester, has resulted in a number of well-researched and well-written papers that incorporate some of the latest research in cell biology. The steps in this project have also led to students who are prepared to address future projects on new and complex topics. The project is part of an undergraduate course in cell biology, but parts of the assignments can be modified to fit a variety of subject areas and levels.

Crop responses to climatic variation

The yield and quality of food crops is central to the well being of humans and is directly affected by climate and weather. Initial studies of climate change on crops focussed on effects of increased carbon dioxide (CO2) level and/or global mean temperature and/or rainfall and nutrition on crop production. However, crops can respond nonlinearly to changes in their growing conditions, exhibit threshold responses and are subject to combinations of stress factors that affect their growth, development and yield. Thus, climate variability and changes in the frequency of extreme events are important for yield, its stability and quality. In this context, threshold temperatures for crop processes are found not to differ greatly for different crops and are important to define for the major food crops, to assist climate modellers predict the occurrence of crop critical temperatures and their temporal resolution. This paper demonstrates the impacts of climate variability for crop production in a number of crops. Increasing temperature and precipitation variability increases the risks to yield, as shown via computer simulation and experimental studies. The issue of food quality has not been given sufficient importance when assessing the impact of climate change for food and this is addressed. Using simulation models of wheat, the concentration of grain protein is shown to respond to changes in the mean and variability of temperature and precipitation events. The paper concludes with discussion of adaptation possibilities for crops in response to drought and argues that characters that enable better exploration of the soil and slower leaf canopy expansion could lead to crop higher transpiration efficiency.

Need for multidisciplinary research towards a second green revolution

Despite recent achievements in conventional plant breeding and genomics, the rate of increase of crop yields is declining and thus there is a need for a second green revolution. Advances within single disciplines, alone, cannot solve the challenges of increasing yield. As scientific disciplines have become increasingly diversified, a more complete understanding of the mechanisms by which genetic and environmental variation modify grain yield and composition is needed, so that specific quantitative and quality targets can be identified. To achieve this aim, the expertise of plant genomics, physiology and agronomy, as well as recently developed plant modelling techniques, must be combined. There has been recent progress in these individual disciplines, but multidisciplinary approaches must be implemented to tackle drought stress and salinity as major constraints to achieving sufficient grain yield in the future.

Effects of MDMA administration on scopolamine-induced disruptions of learning and performance in rats

Functional deficits following short-course high-dose administration of 3,4-methylenedioxymethamphetamine (MDMA) have been difficult to characterize despite evidence indicating that MDMA is neurotoxic in several species. Therefore, the present research used rats trained to respond under a complex behavioral procedure (i.e., a multiple schedule of repeated acquisition and performance of response chains), pharmacological challenge with scopolamine and neurotransmitter assays to examine the effects of MDMA neurotoxicity on learning. Prior to MDMA administration, 0.032-0.32 mg/kg of scopolamine produced dose-dependent rate-decreasing and error-increasing effects in both components of the multiple schedule. Administration of 10 mg/kg of MDMA twice per day for 4 days also produced rate-decreasing and error-increasing effects on these days, but responding returned to baseline levels several days after the final injection. In contrast to the recovery of responding, this regimen of MDMA in untrained rats significantly reduced levels of both serotonin and its major metabolite, 5-hydroxyindoleacetic acid (5-HIAA), for 13-14 days. Furthermore, the rate-decreasing and error-increasing effects of scopolamine were significantly attenuated after MDMA treatment. These results indicate that certain complex operant behaviors rapidly recover from the effects of short-course high-dose MDMA administration, despite the reduced levels of serotonin in the central nervous system (CNS), and that this MDMA-induced loss of serotonin may affect cholinergic transmission.