A simple mechanistic model for predicting cancer induction after fractionated radiotherapy is developed. The model is based upon the linear-quadratic model. The inductions of carcinomas and sarcomas ...are modeled separately. The linear-quadratic model of cell kill is applied to normal tissues which are unintentionally irradiated during a cancer treatment with radiotherapy. Tumor induction is modeled such that each transformation process results in a tumor cell. The microscopic transformation parameter was chosen such that in the limit of low dose and acute exposure, the parameters of the linear-no-threshold model for tumor induction were approached. The differential equations describing carcinoma and sarcoma inductions can be solved analytically. Cancer induction in this model is a function of treatment dose, the cell kill parameters
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α
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, the tumor induction variable
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μ
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, and the repopulation parameter
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. Carcinoma induction shows a bell shaped behavior as long as cell repopulation is small. Assuming large cell repopulation rates, a plateaulike function is approached. In contrast, sarcoma induction is negligible for low doses and increases with increasing dose up to a constant value. The proposed model describes carcinoma and sarcoma inductions after fractionated radiotherapy as an analytical function of four parameters. In the limit of low dose and for an instant irradiation it reproduces the results of the linear-no-threshold model. The obtained dose-response curves for cancer induction can be implemented with other models such as the organ-equivalent dose model to predict second cancers after radiotherapy.
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Farmers’ willingness and ability to adapt agricultural systems depend on their knowledge about changes in climate and perceived risks of extreme events. Using cross-sectional data of 450 farmers ...collected from three agro-ecological zones of Punjab, Pakistan, this study investigates farmer perceptions of climate change and their agreement with observed climatic trends. In addition, this study explores the correlation between different adaptation stages (perceptions, intentions, and adaptation) and their key drivers using a Multivariate Probit Model. This study also explores the adaptation measures adopted by farmers. The results of the study show that the perceptions of increasing mean temperature match well with locally recorded data. However, a discrepancy is found in some cases between farmer perceptions of rainfall changes and local climate records. Moreover, education, experience, land tenure, land holdings, extension, cooperation, access to weather forecasting, and marketing information are the factors influencing the three adaptation stages. A strong association is found among the three adaptation stages. Particularly, the study confirms the hypothesis that accurate perceptions lead to stronger adaptation intentions compared to underestimated or no perceptions. Further, farmers prefer basic adaptation measures including changing crop varieties, input use and planting dates over advanced measures, such as planting shade trees, soil conservation, and crop diversification. The study recommends providing farmers, especially small landholders and tenants, easy access to information, institutional services and training on the use of advanced measures to reduce negative impacts of climate change at the farm level.
The first catalytic use of Ga(0) in organic synthesis has been developed by using a Ag(I) cocatalyst, crownether ligation, and ultrasonic activation. Ga(I)-catalyzed C–C bond formations between ...allyl or allenyl boronic esters and acetals, ketals, or aminals have proceeded in high yields with essentially complete regio- and chemoselectivity. NMR spectroscopic analyses have revealed novel transient Ga(I) catalytic species, formed in situ through partial oxidation of Ga(0) and B–Ga transmetalation, respectively. The possibility of asymmetric Ga(I) catalysis has been demonstrated.
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Recently, an active debate has emerged around greenhouse gas emissions due to indirect land use change (iLUC) of expanding agricultural areas dedicated to biofuel production. In this paper we provide ...a detailed analysis of the iLUC effect, and further address the issues of deforestation, irrigation water use, and crop price increases due to expanding biofuel acreage. We use GLOBIOM – an economic partial equilibrium model of the global forest, agriculture, and biomass sectors with a bottom-up representation of agricultural and forestry management practices. The results indicate that second generation biofuel production fed by wood from sustainably managed existing forests would lead to a negative iLUC factor, meaning that overall emissions are 27% lower compared to the “No biofuel” scenario by 2030. The iLUC factor of first generation biofuels global expansion is generally positive, requiring some 25 years to be paid back by the GHG savings from the substitution of biofuels for conventional fuels. Second generation biofuels perform better also with respect to the other investigated criteria; on the condition that they are not sourced from dedicated plantations directly competing for agricultural land. If so, then efficient first generation systems are preferable. Since no clear technology champion for all situations exists, we would recommend targeting policy instruments directly at the positive and negative effects of biofuel production rather than at the production itself.
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The catalytic use of a sodium amide has been exploited for formal allylic C(sp3)–H bond activation of alkenes under mild conditions. Subsequent C–C bond formations with imines have proceeded in high ...yields with complete regioselectivity and excellent geometric selectivity. Aromatic cyano, chloro, and bromo functionalities are tolerated by the transition metal-free catalyst. Complex amines bearing a CC double bond and distinct heteroaromatic units have been prepared in a single step. The critical importance of sodium versus other s-, p-, d-, and f-block metals as well as metal-free systems has been revealed. In addition, two catalytically active sodium-based intermediates were detected by NMR and HRMS analyses.
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In developed countries, more than half of all cancer patients receive radiotherapy at some stage in the management of their disease. However, a radiation-induced secondary malignancy can be the price ...of success if the primary cancer is cured or at least controlled. Therefore, there is increasing concern regarding radiation-related second cancer risks in long-term radiotherapy survivors and a corresponding need to be able to predict cancer risks at high radiation doses. Of particular interest are second cancer risk estimates for new radiation treatment modalities such as intensity modulated radiotherapy, intensity modulated arc-therapy, proton and heavy ion radiotherapy. The long term risks from such modern radiotherapy treatment techniques have not yet been determined and are unlikely to become apparent for many years, due to the long latency time for solid tumor induction. Most information on the dose-response of radiation-induced cancer is derived from data on the A-bomb survivors who were exposed to γ-rays and neutrons. Since, for radiation protection purposes, the dose span of main interest is between zero and one Gy, the analysis of the A-bomb survivors is usually focused on this range. With increasing cure rates, estimates of cancer risk for doses larger than one Gy are becoming more important for radiotherapy patients. Therefore in this review, emphasis was placed on doses relevant for radiotherapy with respect to radiation induced solid cancer. Simple radiation protection models should be used only with extreme care for risk estimates in radiotherapy, since they are developed exclusively for low dose. When applied to scatter radiation, such models can predict only a fraction of observed second malignancies. Better semi-empirical models include the effect of dose fractionation and represent the dose-response relationships more accurately. The involved uncertainties are still huge for most of the organs and tissues. A major reason for this is that the underlying processes of the induction of carcinoma and sarcoma are not well known. Most uncertainties are related to the time patterns of cancer induction, the population specific dependencies and to the organ specific cancer induction rates. For radiotherapy treatment plan optimization these factors are irrelevant, as a treatment plan comparison is performed for a patient of specific age, sex, etc. If a treatment plan is compared relative to another one only the shape of the dose-response curve (the so called risk-equivalent dose) is of importance and errors can be minimized.
This study estimates the risks of agricultural pesticides on non-target organisms and the environment by combining detailed pesticide application data for 2015 with the Danish risk indicator ...Pesticide Load. We quantify and map the pesticide load of 59 pesticides on 28 crops and pastures in the EU. Furthermore, we investigate how recent bans on 14 pesticides in the EU could reduce pesticide use and load. Key findings show that the highest pesticide loads per hectare occur in Cyprus and the Netherlands due to high application rates and a high proportion of vegetable production. Chlorpyrifos caused the highest pesticide load per hectare on more than half of the assessed crops before its ban. The ban of 14 pesticides between 2018 and 2023 potentially reduced pesticide loads by 94%, but unobserved substitution effects could offset pesticide load reductions. Although bans on active substances are justified to control certain endpoint risks, our results highlight the potential weaknesses of bans that merely shift risks. These findings contribute to the ongoing scientific and societal discourse on efficiently mitigating pesticides' impacts on non-target organisms and the environment. However, to improve the evaluation of pesticide use, it is vital to enhance the reporting on detailed pesticide use for individual crop-pesticide combinations.
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•Quantified pesticide-related risks in the EU with the Pesticide Load•The cultivation of vegetables incurs the highest pesticide load per hectare•Ban of pesticides decreased pesticide load substantially•The substitution of banned pesticides could offset reduction of pesticide load
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The Convention on Biological Diversity's (CBD) strategic plan will expire in 2020, but biodiversity loss is ongoing. Scientists call for more ambitious targets in the next agreement. The ...nature‐needs‐half movement, for example, has advocated conserving half of Earth to solve the biodiversity crisis, which has been translated to protecting 50% of each ecoregion. We evaluated current protection levels of ecoregions in the territory of one of the CBD's signatories, the European Union (EU). We also explored the possible enlargement of the Natura 2000 network to implement 30% or 50% ecoregion coverage in the EU member states’ protected area (PA) network. Based on the most recent land‐use data, we examined whether ecoregions have enough natural area left to reach such high coverage targets. We used a spatially explicit mixed integer programing model to estimate the least‐cost expansion of the PA network based on 3 scenarios that put different emphasis on total conservation cost, ecological representation of ecosystems, or emphasize an equal share of the burden among member states. To realize 30% and 50% ecoregion coverage, the EU would need to add 6.6% and 24.2%, respectively, of its terrestrial area to its PA network. For all 3 scenarios, the EU would need to designate most recommended new PAs in seminatural forests and other semi‐ or natural ecosystems. Because 15 ecoregions did not have enough natural area left to implement the ecoregion‐coverage targets, some member states would also need to establish new PAs on productive land, allocating the largest share to arable land. Thirty percent ecoregion coverage was met by protecting remaining natural areas in all ecoregions except 3, where productive land would also need to be included. Our results support discussions of higher ecoregions protection targets for post‐2020 biodiversity frameworks.
Evaluación y Expansión de la Red de Áreas Protegidas de la Unión Europea hacia Objetivos Potenciales de Cobertura Post 2020
Resumen
El plan estratégico del Convenio sobre la Diversidad Biológica (CBD) expirará en 2020, pero la pérdida de la biodiversidad continúa. Los científicos exigen objetivos más ambiciosos para el siguiente acuerdo. Por ejemplo, la corriente la‐naturaleza‐necesita‐la‐mitad ha abogado por la conservación de la mitad del planeta para resolver la crisis de la biodiversidad, lo que se ha traducido a la protección del 50% de cada ecoregión. Evaluamos los niveles actuales de protección de las ecoregiones en el territorio de uno de los signatarios de la CBD, la Unión Europea (UE). También exploramos el posible crecimiento de la red Natura 2000 para implementar una cobertura del 30% o 50% de las ecoregiones en la red de áreas protegidas (AP) de los estados miembros de la UE. Con base en los datos más recientes de uso de suelo, examinamos si las ecoregiones todavía tienen suficiente área natural como para alcanzar tales objetivos tan altos de cobertura. Usamos un modelo de programación entera mixta espacialmente explícito para estimar la expansión más asequible de la red de AP con base en tres escenarios que colocan un énfasis diferente sobre el costo total de la conservación, la representación ecológica de los ecosistemas o que enfaticen un porcentaje equitativo de la carga entre los estados miembros. Para alcanzar una cobertura del 30% y 50% de las ecoregiones, la UE necesitaría añadir 6.6% y 24.2%, respectivamente, de su área terrestre a la red de AP. Para los tres escenarios, la UE necesitaría designar la mayoría de las nuevas AP recomendadas en bosques seminaturales y en otros ecosistemas semi‐ o totalmente naturales. Debido a que 15 ecoregiones no tenían ya suficiente área natural para implementar los objetivos de cobertura de ecoregiones, algunos estados miembros también necesitarían establecer nuevas AP en suelo productivo, asignando la proporción mayor al suelo arable. La cobertura del 30% de las ecoregiones se alcanzó con la protección de las áreas naturales permanecientes en todas las ecoregiones salvo tres, en donde el suelo productivo también necesitaría estar incluido. Nuestros resultados respaldan las discusiones sobre objetivos más altos de protección de ecoregiones para los marcos de trabajo post 2020 para la biodiversidad.
摘要
《生物多样性公约》的战略计划将于 2020 年到期, 但生物多样性丧失仍在继续。科学家们呼吁, 应在下一份协议中制定更宏伟的目标。例如, “自然需要一半” 运动主张保护半个地球以解决生物多样性危机, 这已经转化为保护每个生态区的 50%。本研究评估了《生物多样性公约》签署方之一的欧盟境内目前的生态区保护水平, 并探讨了将 Natura 2000 网络扩大到覆盖欧盟成员国保护区网络中 30% 或 50% 的生态区的可能性。根据最近的土地使用数据, 我们评估了各个生态区是否有足够的自然面积来实现如此之高的覆盖率目标。我们利用空间显式混合整数规划模型, 基于三种分别强调总保护成本、生态系统的生态代表性和成员国之间的责任均分的不同情景, 估计了保护地网络成本最低的扩张情况。为实现 30% 和 50% 的生态区覆盖率, 欧盟分别需要将其陆地面积的 6.6% 和 24.2% 纳入保护地网络中。在三种情景中, 欧盟最好都应在半天然林或其他半自然生态系统中建立新的保护区。由于有 15 个生态区没有足够的自然面积来实现生态区覆盖目标, 一些成员国还需要在生产土地上建立新的保护区, 将最大承担份额分给了耕地。所有生态区都可以通过保护剩余自然区域来实现 30% 的生态区覆盖率, 但有三个生态区除外, 它们仍需要将生产土地纳入保护地。我们的结果支持为 2020 后生物多样性框架制定更高的生态区保护目标的讨论。 【翻译: 胡怡思; 审校: 聂永刚】
Article impact statement: Greater ecoregion‐protection targets for post‐2020 biodiversity frameworks warrant discussion.
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Nature-Based Solutions (NBS) have been gaining importance in many European cities to reduce floods' impacts. However, evidence of their effectiveness in reducing the impacts of droughts in rural ...areas are scarce. Besides, ignoring future climate conditions or the specific socio-economic context in which NBS is applied could decrease their long-term effectiveness. This study aims to stress the importance of developing scientifically-based and customised information on climate change impacts as a precondition for designing and implementing NBS. For that, a System Dynamic model was developed to analyse and understand the dynamic behaviour of NBS responding to different scenarios of climate change and socio-economic contexts. This article recognises the proactive involvement at all societal levels as an essential component to enhance and maintain ecosystem resilience and, therefore, NBS11MGWB: Medina del Campo Groundwater BodySD: System DynamicsRCP: Representative Concentration PathwaysGW: GroundwaterQSDM: Qualitative System Dynamics ModelGM: Group modelGMB: Group Model BuildingSC: Soil conservationETP: Potential EvapotranspirationEQ: Environmental QualityNJEO: New Jobs and economic opportunitiesSDM: System Dynamics ModelBAU: Business as usual scenarioNBS-NCA: Nature Based Solutions without citizens awareness scenarioeffectiveness. Thus, participatory modelling activities were carried out to engage stakeholders in the model development process to obtain relevant bottom-up information and organise stakeholders' collective knowledge in a graphical structure that captures the system's main dynamics. The Medina del Campo Groundwater Body was used as a frame for the analysis. The study results highlight the need for developing scientifically-based and customised information on the impacts of climate change on NBS as an essential precondition to maintain their long-term effectiveness.
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•Nature-Based Solutions are inherently multidimensional.•Stakeholders knowledge should have real impact on the NBS assessment process.•NBS may not be sufficient to adapt to an intense climate change scenario.•Climate information is an essential precondition to design adaptable NBS.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Genetic testing has familial implications. Counsellors find themselves in (moral) conflict between medical confidentiality (towards the patient) and a potential right or even duty to warn at-risk ...relatives. Legal regulations vary between countries. English literature about German law is scarce. We reviewed the literature of relevant legal cases, focussing on German law, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. This article aims to familiarise counsellors with their responsibilities, compare the situation between countries and point out legally unresolved areas.According to the German Genetic Diagnostics Act (Gendiagnostikgesetz) in case of an 'avoidable or treatable' genetic disorder, geneticists ought to confine themselves to the obligated advice to the patient. Whether a breach of the duty of confidentiality can be justified in exceptional cases by 'necessity as justification' for actively informing relatives at risk remains legally unclear. In case of a 'neither avoidable nor treatable' genetic disease, geneticists should also refrain from actively informing relatives as the justifiable state of emergency does not permit to break the duty of confidentiality.
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