The Impact of Agricultural Research in Tropical Africa: A Study of the Collaboration between the International and National Research Systems

CGIAR Study Paper on the problems and opportunities of international agricultural research in Sub Saharan Africa, and the impact of CGIAR Centers on African national agricultural research systems and on agricultural production and food security in Africa. Written by Hans E. Jahnke, Dieter Kirschke, and Johannes Lagermann and published as CGIAR Study Paper No. 21, part of the series comprising the CGIAR Impact Study of the 1980s

Quantitative Indicators for Priorities in International Agricultural Research

FAO commissioned study by the German consulting firm Gesellschaft fur Agrarprojekte on the selection and use of quantitative indicators for establishing priorities in international agricultural research. The paper discusses the problems of research policy evaluation and the complexities of selecting suitable priority indicators. It describes the uses and limitations of commodity-oriented, resource-oriented, agroecological, and development indicators. Agenda document, TAC 32nd Meeting, October 1983

Effekte der Dünger-N-Form auf das Wurzelwachstum von Winterweizen (Triticum aestivum L.) unter Freilandbedin-gungen auf einem Schwarzerrde-Standort

Auf einem Schwarzerde-Standort konnten in den drei Versuchsjahren 2014–2016 keine eindeutigen Effekte verschiedener Dünger-N-Formen auf die Wurzelentwicklung von Winterweizen erfasst werden. Tendenziell förderte eine NH4+ basierende N Düngung das Wurzelwachstum während des Schossens (BBCH 37), wohingegen sich eine NO3- betonte N-Düngung positiv auf die Wurzelentwicklung zwischen dem Schossen (BBCH 37) und der Blüte (BBCH 65) der Pflanzen auswirkte. Ein Verzicht auf N-Dünger erhöhte im Trend die Durchwurzelung zu Beginn des Schossens (BBCH 32), führte jedoch zu einem teilweise statistisch abgesicherten geringen Wurzelwachstum im Vegetationsverlauf

Entscheidungsunterstützung bei der Gestaltung von Agrarumweltprogrammen

In dem Beitrag wird dargelegt, wie in Zusammenarbeit von Wissenschaft, Politik und Verwaltung kon­krete Entscheidungsunterstützung für die Politikgestaltung in komplexen Systemen geleistet werden kann. Zur Anwendung kommt ein interaktiver PC-gestützter Programmierungsansatz, dessen Möglichkeiten für die Verbesserung von Agrarumweltprogrammen in Sachsen-Anhalt genutzt werden. Gemeinsam mit den betroffenen Akteuren wird auf der Grundlage interaktiv durchgeführter Simulationsrechungen unter Einbeziehung verschiedener Einflussfaktoren (Zielgewichtung, Kofinanzierungssätze und Budgetumfang) eine Strategie zur Verbesserung des Agrarumweltprogramms entwickelt.Peer Reviewe

Retrospective Analysis of Radiological Recurrence Patterns in Glioblastoma, Their Prognostic Value And Association to Postoperative Infarct Volume

Recent studies suggested that postoperative hypoxia might trigger invasive tumor growth, resulting in diffuse/multifocal recurrence patterns. Aim of this study was to analyze distinct recurrence patterns and their association to postoperative infarct volume and outcome. 526 consecutive glioblastoma patients were analyzed, of which 129 met our inclusion criteria: initial tumor diagnosis, surgery, postoperative diffusion-weighted imaging and tumor recurrence during follow-up. Distinct patterns of contrast-enhancement at initial diagnosis and at first tumor recurrence (multifocal growth/progression, contact to dura/ventricle, ependymal spread, local/distant recurrence) were recorded by two blinded neuroradiologists. The association of radiological patterns to survival and postoperative infarct volume was analyzed by uni-/multivariate survival analyses and binary logistic regression analysis. With increasing postoperative infarct volume, patients were significantly more likely to develop multifocal recurrence, recurrence with contact to ventricle and contact to dura. Patients with multifocal recurrence (Hazard Ratio (HR) 1.99, P = 0.010) had significantly shorter OS, patients with recurrent tumor with contact to ventricle (HR 1.85, P = 0.036), ependymal spread (HR 2.97, P = 0.004) and distant recurrence (HR 1.75, P = 0.019) significantly shorter post-progression survival in multivariate analyses including well-established prognostic factors like age, Karnofsky Performance Score (KPS), therapy, extent of resection and patterns of primary tumors. Postoperative infarct volume might initiate hypoxia-mediated aggressive tumor growth resulting in multifocal and diffuse recurrence patterns and impaired survival

Structure-based development of specific inhibitors for individual cathepsins and their medical applications

Specific inhibitors for individual cathepsins have been developed based on their tertiary structures of X-ray crystallography. Cathepsin B-specific inhibitors, CA-074 and CA-030, and cathepsin L specific inhibitors, CLIK-148 and CLIK-195, were designed as the epoxysuccinate derivatives. Cathepsin S inhibitor, CLIK-060, and cathepsin K inhibitor, CLIK-166, were synthesized. These inhibitors can use in vitro and also in vivo, and show no toxicity for experimental animals by the amounts used as the cathepsin inhibitor

Mapping interactions with the chaperone network reveals factors that protect against tau aggregation.

A network of molecular chaperones is known to bind proteins ('clients') and balance their folding, function and turnover. However, it is often unclear which chaperones are critical for selective recognition of individual clients. It is also not clear why these key chaperones might fail in protein-aggregation diseases. Here, we utilized human microtubule-associated protein tau (MAPT or tau) as a model client to survey interactions between ~30 purified chaperones and ~20 disease-associated tau variants (~600 combinations). From this large-scale analysis, we identified human DnaJA2 as an unexpected, but potent, inhibitor of tau aggregation. DnaJA2 levels were correlated with tau pathology in human brains, supporting the idea that it is an important regulator of tau homeostasis. Of note, we found that some disease-associated tau variants were relatively immune to interactions with chaperones, suggesting a model in which avoiding physical recognition by chaperone networks may contribute to disease

Role of regional wetland emissions in atmospheric methane variability

Atmospheric methane (CH4) accounts for ~20% of the total direct anthropogenic radiative forcing by long-lived greenhouse gases. Surface observations show a pause (1999-2006) followed by a resumption in CH4 growth, which remain largely unexplained. Using a land surface model, we estimate wetland CH4 emissions from 1993 to 2014 and study the regional contributions to changes in atmospheric CH4. Atmospheric model simulations using these emissions, together with other sources, compare well with surface and satellite CH4 data. Modelled global wetland emissions vary by ±3%/yr (σ=4.8 Tg), mainly due to precipitation-induced changes in wetland area, but the integrated effect makes only a small contribution to the pause in CH4 growth from 1999 to 2006. Increasing temperature, which increases wetland area, drives a long-term trend in wetland CH4 emissions of +0.2%/yr (1999 to 2014). The increased growth post-2006 was partly caused by increased wetland emissions (+3%), mainly from Tropical Asia, Sourthern Africa and Australia

Rising atmospheric methane: 2007-2014 growth and isotopic shift

From 2007 to 2013, the globally averaged mole fraction of methane in the atmosphere increased by 5.7±1.2ppb yr$^{-1}$. Simultaneously, $\delta^{13}$C$_\text{CH4}$ (a measure of the $^{13}$C/$^{12}$C isotope ratio in methane) has shifted to significantly more negative values since 2007. Growth was extreme in 2014, at 12.5±0.4ppb, with a further shift to more negative values being observed at most latitudes. The isotopic evidence presented here suggests that the methane rise was dominated by significant increases in biogenic methane emissions, particularly in the tropics, for example, from expansion of tropical wetlands in years with strongly positive rainfall anomalies or emissions from increased agricultural sources such as ruminants and rice paddies. Changes in the removal rate of methane by the OH radical have not been seen in other tracers of atmospheric chemistry and do not appear to explain short-term variations in methane. Fossil fuel emissions may also have grown, but the sustained shift to more $^{13}$C-depleted values and its significant interannual variability, and the tropical and Southern Hemisphere loci of post-2007 growth, both indicate that fossil fuel emissions have not been the dominant factor driving the increase. A major cause of increased tropical wetland and tropical agricultural methane emissions, the likely major contributors to growth, may be their responses to meteorological change.This work was supported by the UK Natural Environment Research Council projects NE/N016211/1 The Global Methane Budget, NE/M005836/1 Methane at the edge, NE/K006045/1 The Southern Methane Anomaly and NE/I028874/1 MAMM. We thank the UK Meteorological Office for flask collection and hosting the continuous measurement at Ascension, the Ascension Island Government for essential support, and Thumeka Mkololo for flask collection in Cape Tow