Molecular gas in high redshift QSOs

We review cm and mm observations of thermal molecular line emission from high redshift QSOs. These observations reveal the massive gas reservoirs (10^{10} to 10^{11} M_sun) required to fuel star formation at high rates. We discuss evidence for active star formation in QSO host galaxies, and we show that these high redshift, FIR-luminous QSOs follow the non-linear trend of increasing L_{FIR}/L'(CO) with increasing L_{FIR}. We conclude with a brief discussion of the recent CO detection of the most distant QSO at z=6.42, and its implications for cosmic reionization.Comment: To appear in: Multiwavelength AGN Surveys, eds. Maiolino and Mujica (World Scientific), 8 page

Chemical ecology of animal and human pathogen vectors in a changing global climate.

Infectious diseases affecting livestock and human health that involve vector-borne pathogens are a global problem, unrestricted by borders or boundaries, which may be exacerbated by changing global climate. Thus, the availability of effective tools for control of pathogen vectors is of the utmost importance. The aim of this article is to review, selectively, current knowledge of the chemical ecology of pathogen vectors that affect livestock and human health in the developed and developing world, based on key note lectures presented in a symposium on "The Chemical Ecology of Disease Vectors" at the 25th Annual ISCE meeting in Neuchatel, Switzerland. The focus is on the deployment of semiochemicals for monitoring and control strategies, and discusses briefly future directions that such research should proceed along, bearing in mind the environmental challenges associated with climate change that we will face during the 21st century

Anti-protozoal activity of aporphine and protoberberine alkaloids from Annickia kummeriae (Engl. & Diels) Setten & Maas (Annonaceae)

BACKGROUND: Malaria, trypanosomiasis and leishmaniasis have an overwhelming impact in the poorest countries in the world due to their prevalence, virulence and drug resistance ability. Currently, there is inadequate armory of drugs for the treatment of malaria, trypanosomiasis and leishmaniasis. This underscores the continuing need for the discovery and development of new anti-protozoal drugs. Consequently, there is an urgent need for research aimed at the discovery and development of new effective and safe anti-plasmodial, anti-trypanosomal and anti-leishmanial drugs. METHODS: Bioassay-guided chromatographic fractionation was employed for the isolation and purification of antiprotozoal alkaloids. RESULTS: The methanol extract from the leaves of Annickia kummeriae from Tanzania exhibited a strong anti-plasmodial activity against the multi-drug resistant Plasmodium falciparum K1 strain (IC50 0.12 +/- 0.01 mug/ml, selectivity index (SI) of 250, moderate activity against Trypanosoma brucei rhodesiense STIB 900 strain (IC50 2.50 +/- 0.19 mug/ml, SI 12) and mild activity against Leishmania donovani axenic MHOM-ET-67/82 strain (IC50 9.25 +/- 0.54 mug/ml, SI 3.2). Bioassay-guided chromatographic fractionation led to the isolation of four pure alkaloids, lysicamine (1), trivalvone (2), palmatine (3), jatrorrhizine (4) and two sets of mixtures of jatrorrhizine (4) with columbamine (5) and palmatine (3) with (-)-tetrahydropalmatine (6). The alkaloids showed low cytotoxicity activity (CC50 30 - <90 mug/ml), strong to moderate anti-plasmodial activity (IC50 0.08 +/-

Landing response of <i>G. f. quanzensis</i> on an E-target baited with natural host odours or carbon dioxide dispensed inside a tent.

<p>The landing response is the number of tsetse caught landing on the target expressed as a percentage of the total (landing+circling) catch.</p

Effect of mammalian (A) and lizard (A & B) host odours on trap efficiency.

<p>Trap efficiency was gauged by expressing the mean catch of <i>G. f. fuscipes</i> caught in a trap alone as a percentage of the total catch from the trap+flanking E-net.</p

Landing response of <i>G. f. fuscipes</i> on a large (1×1 m) E-target baited with either (A) mammalian host odours or (B) carbon dioxide dispensed outside a tent, or on a small (0.5 m high×1 m wide) E-target baited with (C) lizard or (D) mammalian host odours.

<p>The landing response is the number of tsetse caught landing on the target expressed as a percentage of the total (landing+circling) catch.</p

Detransformed mean daily catches (transformed mean and standard error of the difference (SED) shown in brackets) of <i>G. f. fuscipes</i> caught over <i>n</i> days from odour-baited devices at various locations in western Kenya.

<p>Carbon dioxide was dispensed within (‘in’) or outside (‘out’) the tent. The detransformed mean daily catch of each odour-baited devices is expressed as a proportion (Index) of that from an unbaited device; asterisks indicate that the index is significantly different from unity at the P<0.05 (*), P<0.01 (**) or P<0.001 (***) levels of probability. Treatments with the same experiment number (Expt.) were incorporated into the same Latin square.</p