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Dans les latitudes tempérées élevées, les ongulés donnent généralement naissance dans une fenêtre temporelle étroite lorsque les conditions sont optimales pour la survie de la progéniture au printemps ou au début de l'été, et utilisent une photopériode changeante pour les conceptions temporelles afin d'anticiper ces conditions. Cependant, dans les basses latitudes tropicales, la variation de la durée du jour est minime et la variation des précipitations rend le cycle saisonnier moins prévisible. Néanmoins, plusieurs espèces d'ongulés conservent des pics de naissance étroits dans de telles conditions, tandis que d'autres montrent que les naissances se propagent assez largement tout au long de l'année. Nous avons étudié comment la variation des précipitations d'une année à l'autre et d'une année à l'autre a influencé le moment de la reproduction de quatre espèces d'ongulés montrant ces modèles contrastés dans la région de Masai Mara au Kenya. Les quatre espèces présentaient des pics de naissance au cours de la période optimale putative au début de la saison humide. Pour le hartebeest et l'impala, le pic de naissance est diffus et la progéniture naît tout au long de l'année. En revanche, le topi et le phacochère ont montré une concentration saisonnière étroite de naissances, avec des conceptions supprimées une fois que les précipitations mensuelles sont tombées en dessous d'un seuil. Les fortes précipitations de la saison précédente et les fortes pluies précoces de l'année en cours ont amélioré la survie au stade juvénile de toutes les espèces, à l'exception de l'impala. Nos résultats révèlent comment la variation des précipitations affectant la croissance des graminées et donc la nutrition des herbivores peut régir la phénologie reproductive des ongulés dans les latitudes tropicales où la variation de la longueur du jour est minime. Le mécanisme sous-jacent semble être la suppression des conceptions une fois que les gains nutritionnels deviennent insuffisants. En réagissant de manière proximale à la variation des précipitations au cours de l'année, les ongulés de la savane tropicale sont moins susceptibles d'être affectés négativement par les conséquences du réchauffement climatique sur la phénologie de la végétation que les ongulés du Nord montrant un contrôle photopériodique plus rigide sur le moment de la reproduction. En latitudes templadas altas, los ungulados generalmente dan a luz dentro de una ventana de tiempo estrecha cuando las condiciones son óptimas para la supervivencia de la descendencia en primavera o principios del verano, y utilizan conceptos cambiantes de fotoperíodo a tiempo para anticipar estas condiciones. Sin embargo, en latitudes tropicales bajas, la variación de la duración del día es mínima, y la variación de las precipitaciones hace que el ciclo estacional sea menos predecible. Sin embargo, varias especies de ungulados conservan picos de nacimiento estrechos en tales condiciones, mientras que otras muestran nacimientos muy extendidos a lo largo del año. Investigamos cómo la variación interanual de las precipitaciones influyó en el tiempo reproductivo de cuatro especies de ungulados que muestran estos patrones contrastantes en la región de Masai Mara en Kenia. Las cuatro especies exhibieron picos de nacimiento durante el periodo óptimo putativo en la estación húmeda temprana. Para hartebeest e impala, el pico de nacimiento era difuso y las crías nacían durante todo el año. Por el contrario, topi y jabalí mostraron una estrecha concentración estacional de nacimientos, con concepciones suprimidas una vez que las precipitaciones mensuales cayeron por debajo de un nivel umbral. Las altas precipitaciones en la temporada anterior y las altas lluvias tempranas en el año en curso mejoraron la supervivencia en la etapa juvenil para todas las especies, excepto los impalas. Nuestros hallazgos revelan cómo la variación de la precipitación que afecta el crecimiento de la hierba y, por lo tanto, la nutrición de los herbívoros, puede gobernar la fenología reproductiva de los ungulados en latitudes tropicales donde la variación de la duración del día es mínima. El mecanismo subyacente parece ser la supresión de las concepciones una vez que las ganancias nutricionales se vuelven insuficientes. Al responder proximalmente a la variación de las precipitaciones dentro del año, es menos probable que los ungulados de la sabana tropical se vean afectados negativamente por las consecuencias del calentamiento global para la fenología de la vegetación que los ungulados del norte que muestran un control fotoperiódico más rígido sobre el tiempo reproductivo. In high temperate latitudes, ungulates generally give birth within a narrow time window when conditions are optimal for offspring survival in spring or early summer, and use changing photoperiod to time conceptions so as to anticipate these conditions. However, in low tropical latitudes day length variation is minimal, and rainfall variation makes the seasonal cycle less predictable. Nevertheless, several ungulate species retain narrow birth peaks under such conditions, while others show births spread quite widely through the year. We investigated how within-year and between-year variation in rainfall influenced the reproductive timing of four ungulate species showing these contrasting patterns in the Masai Mara region of Kenya. All four species exhibited birth peaks during the putative optimal period in the early wet season. For hartebeest and impala, the birth peak was diffuse and offspring were born throughout the year. In contrast, topi and warthog showed a narrow seasonal concentration of births, with conceptions suppressed once monthly rainfall fell below a threshold level. High rainfall in the previous season and high early rains in the current year enhanced survival into the juvenile stage for all the species except impala. Our findings reveal how rainfall variation affecting grass growth and hence herbivore nutrition can govern the reproductive phenology of ungulates in tropical latitudes where day length variation is minimal. The underlying mechanism seems to be the suppression of conceptions once nutritional gains become insufficient. Through responding proximally to within-year variation in rainfall, tropical savanna ungulates are less likely to be affected adversely by the consequences of global warming for vegetation phenology than northern ungulates showing more rigid photoperiodic control over reproductive timing. في خطوط العرض المعتدلة العالية، تلد ذوات الحوافر عمومًا في غضون فترة زمنية ضيقة عندما تكون الظروف مثالية لبقاء النسل في الربيع أو أوائل الصيف، وتستخدم تغيير الفترة الضوئية إلى مفاهيم زمنية لتوقع هذه الظروف. ومع ذلك، في خطوط العرض الاستوائية المنخفضة، يكون تباين طول اليوم ضئيلًا، ويجعل تباين هطول الأمطار الدورة الموسمية أقل قابلية للتنبؤ. ومع ذلك، فإن العديد من الأنواع ذوات الحوافر تحتفظ بقمم ولادة ضيقة في ظل هذه الظروف، في حين أن البعض الآخر يظهر أن الولادات تنتشر على نطاق واسع خلال العام. لقد حققنا في كيفية تأثير التباين في هطول الأمطار خلال العام وبين الأعوام على التوقيت التكاثري لأربعة أنواع من ذوات الحوافر تظهر هذه الأنماط المتناقضة في منطقة ماساي مارا في كينيا. أظهرت جميع الأنواع الأربعة قمم ولادة خلال الفترة المثلى المفترضة في موسم الأمطار المبكر. بالنسبة لحيوان النحل والامبالا، كانت ذروة الولادة منتشرة وولدت ذرية على مدار العام. على النقيض من ذلك، أظهر التوبي والخنزير الحربي تركيزًا موسميًا ضيقًا للولادات، مع قمع المفاهيم بمجرد انخفاض هطول الأمطار الشهري إلى ما دون مستوى العتبة. عزز ارتفاع هطول الأمطار في الموسم السابق وارتفاع الأمطار المبكرة في العام الحالي البقاء على قيد الحياة في مرحلة الشباب لجميع الأنواع باستثناء الإمبالا. تكشف النتائج التي توصلنا إليها كيف أن تباين هطول الأمطار الذي يؤثر على نمو العشب وبالتالي تغذية الحيوانات العاشبة يمكن أن يحكم الفينولوجيا الإنجابية لذوات الحوافر في خطوط العرض الاستوائية حيث يكون تباين طول اليوم ضئيلًا. يبدو أن الآلية الأساسية هي قمع المفاهيم بمجرد أن تصبح المكاسب الغذائية غير كافية. من خلال الاستجابة القريبة من التباين في هطول الأمطار خلال العام، فإن ذوات الحوافر في السافانا الاستوائية أقل عرضة للتأثر سلبًا بعواقب الاحترار العالمي على فينولوجيا الغطاء النباتي من ذوات الحوافر الشمالية التي تظهر تحكمًا دوريًا ضوئيًا أكثر صرامة في توقيت التكاثر.

This article makes the central argument that basic democratic values such as justice, autonomy and participation run the risk of being neglected when designing ‘nudges’ (i.e., indirect suggestions to influence individual behaviour) for sustainable behaviour change in the context of food governance, potentially complicating a democratisation of the food system. ‘Nudges’ uphold freedom of choice while simultaneously advocating a non-coercive soft force of paternalism to help people realise their preferences, maximise societal well-being and meet macro-sustainability goals. While the promises of the ‘nudge’ approach are widely echoed, nudging is also being contested because of its possible anti-democratic effects, such as individualisation, depoliticization and the emphasis of the status of citizens as ‘consumer-citizens.’ From a food democracy perspective, these dangers may undermine efforts to organise collective political action and impede alternative visions of a future food system. Empirically, the article examines specifically how behavioural-economic approaches imagine transitions to a more sustainable food system. By using the “COOP Supermarket of the Future” as a case study, the following analysis will illustrate how private actors are increasingly involved in steering consumer choice towards socially desirable actions. The analysis suggests that the design of choice environments may under specific circumstances increase the susceptibility of individuals to the influence of corporate preferences and simultaneously decrease the prospects for democratic legitimation and decision-making. The article therefore critically assesses whether reforming the food system by altering consumers’ choice-sets and the attribution of personal responsibility, may in fact point towards implicit anti-democratic tenets underlying the ‘will to nudge’ citizens.

Sustainability of agro-food supply chains has recently become the subject of greater interest from consumers, firms, governmental organizations and academia as the environment continues to deteriorate. One of the most critical factors influencing the sustainability of an agro-food supply chain is its network design. A particularly challenging aspect in this context is the broad range of influencing indicators associated with the Triple Bottom Line (TBL) of sustainability that need to be considered. However, many of these indicators could not be fully integrated or measured by single-step optimization problems. This paper presents a critical literature review of operational research methods for the design of sustainable supply chains. A novel two-stage hybrid solution methodology is proposed. In the first stage, a partner selection is performed using a hybrid multi criteria decision making based on Analytic Hierarchy Process (AHP) method and the Ordered Weighted Averaging (OWA) aggregation method. The result obtained in the first stage is used in the second stage to develop a multi-objective mathematical model to optimize the design of the supply chain network. This approach allows the simultaneous consideration of all three dimensions of sustainability including carbon footprint, water footprint, number of jobs created and the total cost of the supply chain design. The proposed approach generates a Pareto frontier to aid users in making decisions. Numerical experiments are completed utilizing data from an agro-food company to demonstrate the efficiency and effectiveness of the proposed solution methodology. The analyzes of the numerical results provide important organizational, practical and policy insights on (1) the impact of financial and environmental sustainability on supply chain network design (2) the tradeoff analysis between environmental emission, water footprint, societal implications and associated cost for making informed decision on supply chain investment.

The ‘4 per mille Soils for Food Security and Climate’ was launched at the COP21 with an aspiration to increase global soil organic matter stocks by 4 per 1000 (or 0.4 %) per year as a compensation for the global emissions of greenhouse gases by anthropogenic sources. This paper surveyed the soil organic carbon (SOC) stock estimates and sequestration potentials from 20 regions in the world (New Zealand, Chile, South Africa, Australia, Tanzania, Indonesia, Kenya, Nigeria, India, China Taiwan, South Korea, China Mainland, United States of America, France, Canada, Belgium, England & Wales, Ireland, Scotland, and Russia). We asked whether the 4 per mille initiative is feasible for the region. The outcomes highlight region specific efforts and scopes for soil carbon sequestration. Reported soil C sequestration rates globally show that under best management practices, 4 per mille or even higher sequestration rates can be accomplished. High C sequestration rates (up to 10 per mille) can be achieved for soils with low initial SOC stock (topsoil less than 30 t C ha− 1), and at the first twenty years after implementation of best management practices. In addition, areas which have reached equilibrium will not be able to further increase their sequestration. We found that most studies on SOC sequestration only consider topsoil (up to 0.3 m depth), as it is considered to be most affected by management techniques. The 4 per mille number was based on a blanket calculation of the whole global soil profile C stock, however the potential to increase SOC is mostly on managed agricultural lands. If we consider 4 per mille in the top 1m of global agricultural soils, SOC sequestration is between 2-3 Gt C year− 1, which effectively offset 20–35% of global anthropogenic greenhouse gas emissions. As a strategy for climate change mitigation, soil carbon sequestration buys time over the next ten to twenty years while other effective sequestration and low carbon technologies become viable. The challenge for cropping farmers is to find disruptive technologies that will further improve soil condition and deliver increased soil carbon. Progress in 4 per mille requires collaboration and communication between scientists, farmers, policy makers, and marketeers.

The developmental and behavioral effects of prenatal exposure to cocaine and/or ethanol were examined in rats. Pregnant rats received ethanol (E; 2 g/kg, b.i.d.) orally, cocaine (C; 6 mg/kg/day, IV), or both (C/E) on gestational days 8-20. Controls consisted of pair-fed (PF) and untreated (UNT) groups. Offspring were weighed and examined for developmental markers beginning postnatal day one (PD1). On PD21 pups were individually observed in an open-field following either an injection of cocaine (10 mg/kg, IP), an injection of saline, or no treatment. Drug-treated and PF dams ate less food and gained less weight than the UNT dams. C and E litters had slightly increased mortality rates. Pups from both the C and E groups appeared less sensitive to the locomotor stimulant effect of cocaine. Pups from the E group engaged in significantly less spontaneous stereotypic locomotion than UNT and PF pups, while male pups from the C group exhibited a decrease in spontaneous exploratory behavior. Thus, prenatal exposure to C or E altered spontaneous and/or cocaine-induced behavior in weanling-aged rats, while the C/E combination did not augment either effect.