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Soil and water conservation in semi-arid Kenya
Sub-Saharan Africa is beset by an increasing population putting stringent demands on a declining resource base. Soil and water conservation (S&WC) is often seen as the primary means to arrest the inevitable decline in soil quality and maintain the productivity of farming systems upon which the majority of the populace rely for their precarious living standards. Yet S&WC programmes have a patchy record: in humid areas they may be relatively successful, but in semi-arid areas there is neither evidence of widespread adoption of S&WC nor increased production. These marginal areas, economically and climatically present the most intractable challenge to natural resource managers. This study investigates the performance of S&WC in rainfed cropping in the drier parts of Kenya, paying particular emphasis to the yield benefits and economic viability of crop production systems for the small scale and most vulnerable of the rural land users. Results are based upon a series of experiments conducted over three crop growing seasons on three soils, testing 10 S&WC based crop production systems with a monocrop of 75-day (short-season) maize (Zea mays L.: var. Makueni composite). The S&WC measures range from physical techniques of contour tillage, tied ridging and terraces to a partly biological technique of trashlines. Hand tillage was taken as the control. In this marginal environment (agro-climatic zones IV and V), the typical situation of smallscale farmers adding no fertilizer was compared with currently recommended levels of application of fertilizer and manure
Fungal Origins of the Bicyclo[2.2.2]diazaoctane Ring System of Prenylated Indole Alkaloids
Over eight different families of natural products, consisting of nearly seventy secondary metabolites, which contain the bicyclo[2.2.2]diazaoctane ring system, have been isolated from various Aspergillus, Penicillium, and Malbranchea species. Since 1968, these secondary metabolites have been the focus of numerous biogenetic, synthetic, taxonomic, and biological studies, and, as such, have made a lasting impact across multiple scientific disciplines. This review covers the isolation, biosynthesis, and biological activity of these unique secondary metabolites containing the bridging bicyclo[2.2.2]diazaoctane ring system. Furthermore, the diverse fungal origin of these natural products is closely examined and, in many cases, updated to reflect the currently accepted fungal taxonomy
Inhibition of Dihydrotestosterone Synthesis in Prostate Cancer by Combined Frontdoor and Backdoor Pathway Blockade
Androgen deprivation therapy (ADT) is palliative and prostate cancer (CaP) recurs as lethal castration-recurrent/resistant CaP (CRPC). One mechanism that provides CaP resistance to ADT is primary backdoor androgen metabolism, which uses up to four 3α-oxidoreductases to convert 5α-androstane-3α,17β-diol (DIOL) to dihydrotestosterone (DHT). The goal was to determine whether inhibition of 3α-oxidoreductase activity decreased conversion of DIOL to DHT. Protein sequence analysis showed that the four 3α-oxidoreductases have identical catalytic amino acid residues. Mass spectrometry data showed combined treatment using catalytically inactive 3α-oxidoreductase mutants and the 5α-reductase inhibitor, dutasteride, decreased DHT levels in CaP cells better than dutasteride alone. Combined blockade of frontdoor and backdoor pathways of DHT synthesis provides a therapeutic strategy to inhibit CRPC development and growth
How Biology Became Social and What It Means for Social Theory
In this paper I first offer a systematic outline of a series of conceptual novelties in
the life-sciences that have favoured, over the last three decades, the emergence of a
more social view of biology. I focus in particular on three areas of investigation: (1)
technical changes in evolutionary literature that have provoked a rethinking of the
possibility of altruism, morality and prosocial behaviours in evolution; (2) changes
in neuroscience, from an understanding of the brain as an isolated data processor to
the ultrasocial and multiply connected social brain of contemporary neuroscience;
and (3) changes in molecular biology, from the view of the gene as an autonomous
master of development to the ‘reactive genome’ of the new emerging field of
molecular epigenetics. In the second section I reflect on the possible implications for
the social sciences of this novel biosocial terrain and argue that the postgenomic
language of extended epigenetic inheritance and blurring of the nature/nurture
boundaries will be as provocative for neo-Darwinism as it is for the social sciences
as we have known them. Signs of a new biosocial language are emerging in several
social-science disciplines and this may represent an exciting theoretical novelty for
twenty-first social theory
Who Sets the Agenda? Analyzing Key Actors and Dynamics of Economic Diversification in Kazakhstan Throughout 2011–2016
This contribution attempts to answer the key question: Who sets the agenda for economic diversification in the context of Kazakhstan? This question remains critical in current scholarly debates. Although Kazakhstan, a young post-Soviet developing nation, has received fair scholarly attention with regard to the agenda setting stage of the policy cycle, the existing literature has yet failed to (1) empirically establish who actually sets the agenda for a certain policy issue and (2) employ the Internet research methods. This paper seeks to fill these gaps. The literature review of Kazakh-specific agenda setting publications suggests that among the major actors, the government tends to exert predominant influence, though other actors may also play a role, for example, media and academia. This research is driven by Internet penetration rate data and focuses on the period from January 2011 until December 2016. The findings lead to two key conclusions. First, think tanks seem to set the government agenda for economic diversification policy in Kazakhstan. Second, the government, while exhibiting the larger agenda setting magnitude vis-à-vis the other actors, shapes the subsequent debates as measured by the number of relevant references in media, think tanks, and academic publications. This research seeks to contribute to existing agenda setting theories in the Internet era by defining the most important actor(s), specifically in the Kazakh context based on longitudinal dynamics in attention
Ideological cultures and media discourses on scientific knowledge: re-reading news on climate change
Focusing on the representation of climate change in the British “quality press,” this article argues that the discursive (re)construction of scientific claims in the media is strongly entangled with ideological standpoints. Understood here as a set of ideas and values that legitimate a program of action vis-à-vis a given social and political order, ideology works as a powerful selection device in deciding what is scientific news, i.e. what the relevant “facts” are, and who are the authorized “agents of definition” of science matters. The representation of scientific knowledge has important implications for evaluating political programs and assessing the responsibility of both governments and the public in addressing climate change
Collaboration and knowledge exchange between scholars in Britain and the empire, 1830–1914
In recent years there has been a growing interest among historians in the British Empire as a space of knowledge production and circulation. Much of this work assumes that scholarly cooperation and collaboration between individuals and institutions within the Empire had the effect (and often also the aim) of strengthening both imperial ties and the idea of empire. This chapter argues, however, that many examples of scholarly travel, exchange, and collaboration were undertaken with very different goals in mind. In particular, it highlights the continuing importance of an ideal of scientific internationalism, which stressed the benefits of scholarship for the whole of humanity and prioritized the needs and goals of individual academic and scientific disciplines. As the chapter shows, some scholars even went on to develop nuanced critiques of the imperial project while using the very structures of empire to further their own individual, disciplinary and institutional goals
Two Genetic Determinants Acquired Late in Mus Evolution Regulate the Inclusion of Exon 5, which Alters Mouse APOBEC3 Translation Efficiency
Mouse apolipoprotein B mRNA-editing enzyme catalytic polypeptide-like editing complex 3 (mA3), an intracellular antiviral factor, has 2 allelic variations that are linked with different susceptibilities to beta- and gammaretrovirus infections among various mouse strains. In virus-resistant C57BL/6 (B6) mice, mA3 transcripts are more abundant than those in susceptible BALB/c mice both in the spleen and bone marrow. These strains of mice also express mA3 transcripts with different splicing patterns: B6 mice preferentially express exon 5-deficient (Δ5) mA3 mRNA, while BALB/c mice produce exon 5-containing full-length mA3 mRNA as the major transcript. Although the protein product of the Δ5 mRNA exerts stronger antiretroviral activities than the full-length protein, how exon 5 affects mA3 antiviral activity, as well as the genetic mechanisms regulating exon 5 inclusion into the mA3 transcripts, remains largely uncharacterized. Here we show that mA3 exon 5 is indeed a functional element that influences protein synthesis at a post-transcriptional level. We further employed in vitro splicing assays using genomic DNA clones to identify two critical polymorphisms affecting the inclusion of exon 5 into mA3 transcripts: the number of TCCT repeats upstream of exon 5 and the single nucleotide polymorphism within exon 5 located 12 bases upstream of the exon 5/intron 5 boundary. Distribution of the above polymorphisms among different Mus species indicates that the inclusion of exon 5 into mA3 mRNA is a relatively recent event in the evolution of mice. The widespread geographic distribution of this exon 5-including genetic variant suggests that in some Mus populations the cost of maintaining an effective but mutagenic enzyme may outweigh its antiviral function
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