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Global environmental change has influenced lake surface temperatures, a key driver of ecosystem structure and function. Recent studies have suggested significant warming of water temperatures in individual lakes across many different regions around the world. However, the spatial and temporal coherence associated with the magnitude of these trends remains unclear. Thus, a global data set of water temperature is required to understand and synthesize global, long-term trends in surface water temperatures of inland bodies of water. We assembled a database of summer lake surface temperatures for 291 lakes collected in situ and/or by satellites for the period 1985-2009. In addition, corresponding climatic drivers (air temperatures, solar radiation, and cloud cover) and geomorphometric characteristics (latitude, longitude, elevation, lake surface area, maximum depth, mean depth, and volume) that influence lake surface temperatures were compiled for each lake. This unique dataset offers an invaluable baseline perspective on global-scale lake thermal conditions as environmental change continues.

Influenza virus poses a difficult challenge for protective immunity. This virus is adept at altering its surface proteins, the proteins that are the targets of neutralizing antibody. Consequently, each year a new vaccine must be developed to combat the current recirculating strains. A universal influenza vaccine that primes specific memory cells that recognise conserved parts of the virus could prove to be effective against both annual influenza variants and newly emergent potentially pandemic strains. Such a vaccine will have to contain a safe and effective adjuvant that can be used in individuals of all ages. We examine protection from viral challenge in mice vaccinated with the nucleoprotein from the PR8 strain of influenza A, a protein that is highly conserved across viral subtypes. Vaccination with nucleoprotein delivered with a universally used and safe adjuvant, composed of insoluble aluminium salts, provides protection against viruses that either express the same or an altered version of nucleoprotein. This protection correlated with the presence of nucleoprotein specific CD8 T cells in the lungs of infected animals at early time points after infection. In contrast, immunization with NP delivered with alum and the detoxified LPS adjuvant, monophosphoryl lipid A, provided some protection to the homologous viral strain but no protection against infection by influenza expressing a variant nucleoprotein. Together, these data point towards a vaccine solution for all influenza A subtypes.

Primary production (PP) in Lake Peipsi-Pihkva, the tripartite borderwaterbody between Estonia and Russia, was first measured in 1965-1966. Since 1970 there exists a continuous timeseries of monthly PP measurements from May to October. Detailed investigations of the seasonaland daily dynamics as well as the vertical distribution of PP were carried out in 1985-1987. The long-term average values of integral PP (PP{sub}int{end}) in Lakes Peipsi and Pihkva were equal (0.8 g C m{sup}-2{end} d{sup}-1{end}), although the values per cubic metre (PP{sub}max{end},) differed more than twofold and characterized L. Pihkva asa eutrophic lake and L. Peipsi as a transition type between meso- and eutrophic lakes. The years from 1973 to 1980, 1987 and 1991 were oflow productivity, while in 1971, 1983, 1988 and 1990 PP peaks occurred in both lakes. In the seasonal pattern PP{sub}int{end} had peaks in May and July. In June, after the spring bloom, PP as well as the chlorophyll a (Chl) and ATP content were low. The high Chl peak in autumn was probably built up by the degradation products of chlorophyll, as neither PP nor ATP increased. Seasonal changes in integral PP in L. peipsi could be well described R{sup}2{end} = 0.91) by an empiricalmodel relating PP{sub}int{end} to PP{sub}max{end}, Secchi depth (S) and total solar radiation (Q). In mixed conditions prevailing in bothlakes, PP was inhibited in the surface layer and its maximum was located at a depth of 0.25 ... 0.5 S. The threshold total solar radiation level for the onset of inhibition was between 1200 and 2000 kJ m{sup}-2{end} h{sup}-1{end} in May and July, and decreased to less than500 kJ m{sup}-2{end} h{sup}-1{end} in October. As a rule, inhibitionstarted in the morning at a higher irradiance than necessary for keeping it up during evening hours . When compared with PP{sub}max{end} , photosynthesis in the surface layer at noon was suppressed by 56 percent in May, by 45 percent in July and by 40 percent in October. [ABSTRACT FROM AUTHOR]

Lake Peipsi-Pihkva (3555 km{sup}2{end} , mean depth 8.3 m), consisting of three parts, (L. Peipsi, L. Pihkva, L. Lammijarv) is located onthe border of Estonia and Russia. L. Peipsi belongs to unstratified eutrophic lakes with mesotrophic features, L. Lammijarv has some dyseutrophic features, while L. Pihkva is strongly eutrophic. The total annual nutrient load is 15.57 tons N km{sup}-2{end} and 327 kgP km{sup}-2{end} with 74 percent of N and 39 percent of P originating from agriculture. The mean concentrations of total N and P in the lake are 876 mg m{sup}-3{end} -3 and 46 mg m{sup}-3{end} , respectively, both being the highest in L. Pihkva and the lowest in the northern part of L. Peipsi. Average pH is 8.14 and Secchi disk transparency 1.63 m. Diatoms and blue-green algae prevail in phytoplankton biomass. The blue-greens Gloeotrichia echinulata and Aphanizomenon flos-aquae dominatein summer causing the water-blooms. The concentration of Chla was the lowest in the northern part of L. Peipsi (mean 14.7 mg m{sup}-3{end} ) and the highest in the southern part of L. Pihkva (mean 47.9 mg m{sup}-3{end} , median 16.3 mg m{sup}-3{end} ). An increase of Chla and decrease of Secchi depth could be noticed in 1983-1988, while in 1988-1994 the tendency was opposite. The long-term average primary production is 0.8 g C m{sup}-2{end} d{sup}-1{end} . Zooplankton is remarkably rich in species, the average biomass in the vegetative period being 2-3 g m{sup}-3{end} and production 22 g C m{sup}- 2{end}. The role of rotifers in production is 53 percent followed by that of cladocerans (30 percent), copepods (16 percent) and Dreissena polymorpha larvae (1 percent). The total count of bacteria is 1-9 million cells perml. Chironomus plumosus and Potamothrix hammoniensis are dominating in the profundal. The average abundance of macrozoobenthos (without big molluscs) 2617 ind. m{sup}-2{end} , and their biomass 12.34 g m{sup}-2{end} are considered to be the highest among the large lakes of Nort [ABSTRACT FROM AUTHOR]