The role of the pod in seed development: strategies for manipulating yield

Pods play a key role in encapsulating the developing seeds and protecting them from pests and pathogens. In addition to this protective function, it has been shown that the photosynthetically active pod wall contributes assimilates and nutrients to fuel seed growth. Recent work has revealed that signals originating from the pod may also act to coordinate grain filling and regulate the reallocation of reserves from damaged seeds to those that have retained viability. In this review we consider the evidence that pods can regulate seed growth and maturation, particularly in members of the Brassicaceae family, and explore how the timing and duration of pod development might be manipulated to enhance either the quantity of crop yield or its nutritional properties.

The timing of anthropogenic emergence in simulated climate extremes

Determining the time of emergence of climates altered from their natural state by anthropogenic influences can help inform the development of adaptation and mitigation strategies to climate change. Previous studies have examined the time of emergence of climate averages. However, at the global scale, the emergence of changes in extreme events, which have the greatest societal impacts, has not been investigated before. Based on state-of-the-art climate models, we show that temperature extremes generally emerge slightly later from their quasi-natural climate state than seasonal means, due to greater variability in extremes. Nevertheless, according to model evidence, both hot and cold extremes have already emerged across many areas. Remarkably, even precipitation extremes that have very large variability are projected to emerge in the coming decades in Northern Hemisphere winters associated with a wettening trend. Based on our findings we expect local temperature and precipitation extremes to already differ significantly from their previous quasi-natural state at many locations or to do so in the near future. Our findings have implications for climate impacts and detection and attribution studies assessing observed changes in regional climate extremes by showing whether they will likely find a fingerprint of anthropogenic climate change.

The effects of uncertainty about the timing of deals on consumer behavior

I examine the effects of uncertainty about the timing of de aIs (i.e. temporary price cuts or sales) on consumer behavior in a dynamic inventory model of consumer choice. I derive implications for purchase behavior and test them empirically, using two years of scanner data for soft drinks. I fmd that loyal consumers' decisions, both about the allocation of their purchases over time and the quantity to be purchased in a particular deal, are affected by the uncertainty about the timing of the deal for the product. Loyal consumers buy a higher fraction of their overall purchases during de ais as the uncertainty decreases. This effect increases with an increase in the product' s share of a given consumer' s purchase in the same category or if the consumer stockpiles (i.e., is a shopper). During a particular deal, loyal shoppers increase the quantity they purchase the more time that has passed since the previous de aI, and the higher the uncertainty about the deals' timing. For the non-Ioyal consumers these effects are not significant. These results hold for products that are frequently purchased, like soft-drinks and yogurt, but do not hold for less frequentIy purchased products, such as laundry detergents. The fmdings suggest that manufacturers and retailers should incorporate the effects of deals' timing on consumers' purchase' decisions when deriving optimal pricing strategies.

Is rainfall seasonality important for reproductive strategies in viviparous Neotropical pit vipers? A case study with Bothrops leucurus from the Brazilian Atlantic Forest

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

IMPROVING STARTABILITY AND REDUCING EMISSIONS IN FLEXFUEL SPARK IGNITION DIRECT INJECTION VARIABLE CAM TIMING ENGINE

Experimental work and analysis was done to investigate engine startup robustness and emissions of a flex-fuel spark ignition (SI) direct injection (DI) engine. The vaporization and other characteristics of ethanol fuel blends present a challenge at engine startup. Strategies to reduce the enrichment requirements for the first engine startup cycle and emissions for the second and third fired cycle at 25°C ± 1°C engine and intake air temperature were investigated. Research work was conducted on a single cylinder SIDI engine with gasoline and E85 fuels, to study the effect on first fired cycle of engine startup. Piston configurations that included a compression ratio change (11 vs 15.5) and piston geometry change (flattop vs bowl) were tested, along with changes in intake cam timing (95,110,125) and fuel pressure (0.4 MPa vs 3 MPa). The goal was to replicate the engine speed, manifold pressure, fuel pressure and testing temperature from an engine startup trace for investigating the first fired cycle for the engine. Results showed bowl piston was able to enable lower equivalence ratio engine starts with gasoline fuel, while also showing lower IMEP at the same equivalence ratio compared to flat top piston. With E85, bowl piston showed reduced IMEP as compression ratio increased at the same equivalence ratio. A preference for constant intake valve timing across fuels seemed to indicate that flattop piston might be a good flex-fuel piston. Significant improvements were seen with higher CR bowl piston with high fuel pressure starts, but showed no improvement with low fuel pressures. Simulation work was conducted to analyze initial three cycles of engine startup in GT-POWER for the same set of hardware used in the experimentations. A steady state validated model was modified for startup conditions. The results of which allowed an understanding of the relative residual levels and IMEP at the test points in the cam phasing space. This allowed selecting additional test points that enable use of higher residual levels, eliminating those with smaller trapped mass incapable of producing required IMEP for proper engine turnover. The second phase of experimental testing results for 2nd and 3rd startup cycle revealed both E10 and E85 prefer the same SOI of 240°bTDC at second and third startup cycle for the flat top piston and high injection pressures. E85 fuel optimal cam timing for startup showed that it tolerates more residuals compared to E10 fuel. Higher internal residuals drives down the Ø requirement for both fuels up to their combustion stability limit, this is thought to be direct benefit to vaporization due to increased cycle start temperature. Benefits are shown for an advance IMOP and retarded EMOP strategy at engine startup. Overall the amount of residuals preferred by an engine for E10 fuel at startup is thought to be constant across engine speed, thus could enable easier selection of optimized cam positions across the startup speeds.

Evaluating the optimal timing of surgical antimicrobial prophylaxis: study protocol for a randomized controlled trial

BACKGROUND Surgical site infections are the most common hospital-acquired infections among surgical patients. The administration of surgical antimicrobial prophylaxis reduces the risk of surgical site infections . The optimal timing of this procedure is still a matter of debate. While most studies suggest that it should be given as close to the incision time as possible, others conclude that this may be too late for optimal prevention of surgical site infections. A large observational study suggests that surgical antimicrobial prophylaxis should be administered 74 to 30 minutes before surgery. The aim of this article is to report the design and protocol of a randomized controlled trial investigating the optimal timing of surgical antimicrobial prophylaxis.Methods/design: In this bi-center randomized controlled trial conducted at two tertiary referral centers in Switzerland, we plan to include 5,000 patients undergoing general, oncologic, vascular and orthopedic trauma procedures. Patients are randomized in a 1:1 ratio into two groups: one receiving surgical antimicrobial prophylaxis in the anesthesia room (75 to 30 minutes before incision) and the other receiving surgical antimicrobial prophylaxis in the operating room (less than 30 minutes before incision). We expect a significantly lower rate of surgical site infections with surgical antimicrobial prophylaxis administered more than 30 minutes before the scheduled incision. The primary outcome is the occurrence of surgical site infections during a 30-day follow-up period (one year with an implant in place). When assuming a 5 surgical site infection risk with administration of surgical antimicrobial prophylaxis in the operating room, the planned sample size has an 80% power to detect a relative risk reduction for surgical site infections of 33% when administering surgical antimicrobial prophylaxis in the anesthesia room (with a two-sided type I error of 5%). We expect the study to be completed within three years. DISCUSSION The results of this randomized controlled trial will have an important impact on current international guidelines for infection control strategies in the hospital. Moreover, the results of this randomized controlled trial are of significant interest for patient safety and healthcare economics.Trial registration: This trial is registered on ClinicalTrials.gov under the identifier NCT01790529.

A study of the association between timing of solid food introduction in infants and overweight and obesity in pre-school aged children in NHANES 2003-2008

Background. Previous studies suggest an association between timing of introduction of solid food and increased risk of obesity in pre-school aged children, but no study included a representative sample of US children. We sought to examine whether there was any association between the timing of solid food introduction and overweight/obesity in pre-school aged children. Design/methods. Cross-sectional study of a nationally representative sample (N=2050) of US children aged 2 to 5 years with information on infant feeding practices and measured weight and height from the National Health and Nutrition Examination Survey 2003–2008. The main outcome measure was BMI for age and sex ≥ 85th percentile. The main exposure was timing of solid food introduction at < 4, 4–5, or ≥ 6 months of age. Binomial logistic regression was used in the analysis controlling for child's sex, birth weight and breastfeeding status as well as maternal age at birth, smoking status and socio-demographic variables. Results. Two thousand and fifty children were included in the sample; 51% male and 49% female; 57.1% Non-Hispanic White, 21.9% Hispanic, 14.0% Non-Hispanic Black, and 7% other race/ethnicity. Twenty-two percent of the children were overweight or obese. Sixty-nine percent were breastfed or fed breast milk at birth and 36% continued breastfeeding for ≥ six months. Solid foods were introduced before 4 months of age for 11.2% of the children; 30.3% received solid foods between 4 to 5 months; with 58.6% receiving solid foods at 6 months or later. Timing of solid food introduction was not associated with weight status (OR= 1.36, 95% CI [0.83–2.24]). Formula-fed infants and infants breastfed for < 4 months had increased odds of overweight and obesity (OR=1.54, 95% CI [1.05–2.27] and OR= 1.60, 95% CI [1.05–2.44], respectively) when compared to infants breastfed for ≥ 6 months. Conclusion. Timing of solid food introduction was not associated with weight status in a national sample of US children ages 2 to 5 years. More focus should be placed on promoting breastfeeding and healthy infant feeding practices as strategies to prevent obesity in children. ^

Stochastic dynamic programming for election timing: A game theory approach

In this paper, we consider dynamic programming for the election timing in the majoritarian parliamentary system such as in Australia, where the government has a constitutional right to call an early election. This right can give the government an advantage to remain in power for as long as possible by calling an election, when its popularity is high. On the other hand, the opposition's natural objective is to gain power, and it will apply controls termed as "boosts" to reduce the chance of the government being re-elected by introducing policy and economic responses. In this paper, we explore equilibrium solutions to the government, and the opposition strategies in a political game using stochastic dynamic programming. Results are given in terms of the expected remaining life in power, call and boost probabilities at each time at any level of popularity.

Az euróövezet bővítése és euróbevezetési stratégiák (Euro-area enlargement and euro adoption strategies)

Tanulmányunk azokat a kockázatokat és kihívásokat vizsgálja, amelyekkel az új EU tagállamok szembesülnek az euróhoz vezető úton, valamint elemzi az euró bevezetésével és a bevezetés időzítésével kapcsolatos stratégiákat is. Megvizsgáljuk a reál- és nominálkonvergencia kapcsolatát az euróövezetbe csatlakozás szemszögéből. Véleményünk szerint a gazdaság egy főre jutó jövedelemben mért kezdeti fejlettségi szintje, valamint a reálkonvergencia sebessége kihatnak a követendő stratégiákra és a belépés időzítésére. Minél alacsonyabb ugyanis egy ország egy főre jutó jövedelme, annál nagyobb az árszínvonalbeli lemaradása (amit be kell hoznia), és az új tagok jelenlegi helyzetét figyelembe véve annál nagyobb a veszélye annak, hogy a hitelek növekedése túlzottá, a gazdaság túlfűtötté válik. Úgy gondoljuk, hogy az inflációkövetés lebegő árfolyam mellett megfelelőbb az árszínvonal felzárkózási folyamatának kezelésére, mint valamilyen merev árfolyamrögzítés. Elemezzük a maastrichti kritériumokat az új EU-tagállamok gazdasági jellemzőinek szempontjából, és az inflációs kritérium módosítását javasoljuk, amely jelenlegi formájában elvesztette közgazdasági értelmét. JEL kód: E31, E52, E60, F30. /===/ This paper commissioned by DG ECFIN from the EU Commission as part of the EMU@10 project and published in Hungarian by the permission of the EU Commission. The origi-nal English version is available at http://ec.europa.eu/economy_finance/publications/ publication_summary12103_en.htm. The paper discusses the risks and challenges faced by new members on the road to the euro and the strategies and timing of euro adoption. It investigates the real/nominal convergence nexus from the perspective of euro-area entry, arguing that the initial level of economic development, as measured by per capita income, and the speed of real convergence have a bearing on the strategies to follow and the timing of entry into the euro area, for the lower per capita income is, the larger is the price-level gap to close and the greater the danger of credit booms and overheating. It is argued argue that inflation targeting with floating rates is better suited than hard pegs to managing the price-level catch-up process. A suggestion is made for modifying the Maastricht inflation criterion, which as currently defined has lost its economic logic.

Endogenous Timing of Moves in Bertrand-Edgeworth Triopolies

We determine the endogenous order of moves in which the firms set their prices in the framework of a capacity-constrained Bertrand-Edgeworth triopoly. A three-period timing game that determines the period in which the firms announce their prices precedes the price-setting stage. We show for the non-trivial case (in which the Bertrand-Edgeworth triopoly has only an equilibrium in non-degenerated mixed-strategies) that the firm with the largest capacity sets its price first, while the two other firms set their prices later. Our result extends a finding by Deneckere and Kovenock (1992) from duopolies to triopolies. This extension was made possible by Hirata's (2009) recent advancements on the mixed-strategy equilibria of Bertrand-Edgeworth games.

The Impact of Proactive Strategies on Market Performance in Economic Downturn: the Case of Hungary

Recession in 2008/09 affected almost all the European countries seriously but some of them were hurt to greater extent. The timing of economic downturns can never be appropriate but it found Hungary at the time when it was in a vulnerable condition leading to a prolong struggle to find the way out. However, each company’s own experience and approach in crisis can differ from what the whole economy would explain. This study aims to contribute to the emerging research field regarding the concept of proactive marketing. We investigated the relationship between approach to crisis as an opportunity and market performance. Based on a survey of 173 companies we demonstrated that proactive marketing can lead to better performance but larger companies have the advantage of implementing this strategy more successfully.

Satellite tracking derived insights into migration and foraging strategies of male loggerhead turtles in the eastern Atlantic

[EN] In recent years, information about the movements and timing of migration by male sea turtles has begun to be unraveled. Here, we present the first satellite tracking of male loggerhead sea turtles (Caretta caretta) in the eastern Atlantic. Satellite linked transmitters were attached to five adult males, captured in the near shore waters off Boavista, Republic of Cape Verde. This archipelago hosts the single most important breeding site of loggerhead turtles in the eastern Atlantic.

Of sets of offsets: Cumulative impacts and strategies for compensatory restoration

Biodiversity offsets are increasingly advocated as a flexible approach to managing the ecological costs of economic development. Arguably, however, this remains an area where policy-making has run ahead of science. A growing number of studies identify limitations of offsets in achieving ecologically sustainable outcomes, pointing to ethical and implementation issues that may undermine their effectiveness. We develop a novel system dynamic modelling framework to analyze the no net loss objective of development and biodiversity offsets. The modelling framework considers a marine-based example, where resource abundance depends on a habitat that is affected by a sequence of development projects, and biodiversity offsets are understood as habitat restoration actions. The model is used to explore the implications of four alternative offset management strategies for a regulator, which differ in how net loss is measured, and whether and how the cumulative impacts of development are considered. Our results confirm that, when it comes to offsets as a conservation tool, the devil lies in the details. Approaches to determining the magnitude of offsets required, as well as their timing and allocation among multiple developers, can result in potentially complex and undesired sets of economic incentives, with direct impacts on the ability to meet the overall objective of ecologically sustainable development. The approach and insights are of direct interest to conservation policy design in a broad range of marine and coastal contexts.

The timing and interval of mate encounter affects investment during mating

The benefits obtained from mating are usually condition-dependent, favouring the evolution of flexible investment during copulation, for instance, in terms of invested time, energy, or sperm. Flexible investment strategies are predicted to depend on the likelihood of acquiring alternative mates and therefore they should depend on the timing of mate encounter. However, scarce experimental evidence for this hypothesis exists. Here we manipulated the time delay until first mating and the interval between first and second mating in the polygynandrous common lizard, Zootoca vivipara. We determined treatment effects on fertilisation success and copulation duration, the latter being a proxy for investment in mating and for quantity of transferred sperm. The duration of the second copulation decreased with increasing inter-mating interval and depended on the fertilisation success of first mates. The former provides evidence for time-dependent investment strategies, most likely resulting from the progression of the female's reproductive cycle. Fertilisation success of first mates increased with increasing inter-mating interval and was higher when females were closer to ovulation, showing that flexible investment strategies significantly affected male reproductive success. This points to fertilisation assurance, which may mitigate negative effects of low population density on reproductive success, e.g. Allee effects.

Timing versus caloric goal in nutritional therapy for critically ill patients

Introduction: Enteral nutrition is an important therapy for severely critically ill patients. The timing and amount of energy have been highly debated. Objective: The aim of the present study was to directly compare the timing and the caloric targets in critically ill patients. Methods: Retrospective cohort study conducted at a single center, comparing timing and caloric goal for critically ill patients. Patients were stratified according to the start of nutritional therapy (24, 48, or more than 48 h) and the amount of energy delivered (target adequacy of previously calculated percentage in the first week). Statistical analysis was performed using parametric and non-parametric tests for independent samples and logistic regression. The results were expressed as mean ± standard deviation or incidence and percentage. Results and discussion: There were no differences in major clinical outcomes in relation to the achievement of percentage of caloric goal at the end of the first week of the study. The beginning of caloric intake on the first day of hospitalization was associated with reduced mortality in the intensive care unit, but not with hospital mortality. The strategy of an early and limited amount of calories seems to be associated with a better outcome. Prospective studies evaluating and comparing these strategies are recommended.