A New Insight on the Preparation of Stabilized Alpha-Nickel Hydroxide Nanoparticles

Nickel hydroxide can provide an outstanding cathode material in alkaline secondary batteries, however the progressive decrease of the charge capacity as a function of the number of oxidation/reduction cycles is a challenging problem to be solved. New improvements on the electrochemical properties of electrode materials can be achieved by exploiting the much better performance of alpha-nickel hydroxide. Such materials were obtained in a stable form by sol-gel method and characterized by thermogravimetric analyses, UV-Vis spectroscopy, X-ray diffractometry, scanning and transmission electron microscopy, cyclic voltammetry and electrochemical quartz crystal microbalance techniques. The results revealed not only the formation of the alpha-Ni(OH)(2) phase, but also a much better electrochemical reversibility and stability as compared with similar materials obtained by electrochemical precipitation method.

Using Polycarbonate Membranes as Templates for the Preparation of Au Nanostructures for Surface-Enhanced Raman Scattering

Polycarbonate membranes (PCM) of various pores sizes (400, 200, 100 and 50 nm) were used as templates for gold deposition. The electrodeposition from gold ions resulted in the formation of gold nanotubes when large pores size PCMs (400 and 200 nm) were used. On the other hand, gold nanowires were predominant for the PCMs with smaller pores size (100 and 50 nm). Surface-enhanced Raman scattering (SERS) from the probe molecule 4-mercaptopyridine (4-MPy) was obtained from all these nanostructures. The SERS efficiency of the substrates produced using the PC M templates were compared to two commonly used SERS platforms: a roughened gold electrode and gold nanostructures electrodeposited through organized polystyrene spheres (PSS). The SERS signal of the probe molecule increased as the pore diameter of the PCM template decreased. Moreover, the SERS efficiency from the nanostructures produced using 50 nm PCM templates was four and two times better than the signal from the roughened gold electrode and the PSS template, respectively. The SERS substrates prepared using PCM templates were more homogenous over a larger area (ca. 1 cm(2)), presented better spatial and sample to sample reproducibility than the other substrates. These results show that SERS substrates prepared using PCM templates are promising for the fabrication of planar SERS platforms for analytical/bioanalytical applications.

Mild mitochondrial uncoupling in mice affects energy metabolism, redox balance and longevity

Caloric restriction is the most effective non-genetic intervention to enhance lifespan known to date. A major research interest has been the development of therapeutic strategies capable of promoting the beneficial results of this dietary regimen. In this sense, we propose that compounds that decrease the efficiency of energy conversion, such as mitochondrial uncouplers, can be caloric restriction mimetics. Treatment of mice with low doses of the protonophore 2,4-dinitrophenol promotes enhanced tissue respiratory rates, improved serological glucose, triglyceride and insulin levels, decrease of reactive oxygen species levels and tissue DNA and protein oxidation, as well as reduced body weight. Importantly, 2,4-dinitrophenol-treated animals also presented enhanced longevity. Our results demonstrate that mild mitochondrial uncoupling is a highly effective in vivo antioxidant strategy, and describe the first therapeutic intervention capable of effectively reproducing the physiological, metabolic and lifespan effects of caloric restriction in healthy mammals.

Kolerahanteringen i Falun år 1834 & 1853 : En studie av sundhetsnämndens agerande

Syftet med uppsatsen är att undersöka vilka åtgärder som Falu stad, genom sundhetsnämnden, vidtog när farsoten kolera spreds i Sverige år 1834 respektive år 1853 samt om dessa åtgärder skiljer sig över tid. Frågeställningarna som används är: Vilka förebyggande åtgärder mot kolera vidtog staden genom sundhetsnämnden år 1834 och år 1853? Hur agerade läkarna i Falun mot kolerahotet? Skiljer sig Falu sundhetsnämnds åtgärder i jämförelse med andra städers sundhetsnämnder? Skiljer sig sundhetsnämndens åtgärder mellan åren 1834 och 1853? Materialet som används består av sundhetsnämndens mötesprotokoll från åren 1834 och år 1853, kolerakungörelser från de båda tidpunkterna, stadsläkare- och gruvläkarapporter samt utdrag från Tidning för Falu län och stad. Resultatet visar, att Falun vid båda tillfällena spärrades av genom att vaktstationer upprättades vid vägarna och vid stadens gräns. En karantänsstation upprättades vid stadens hälsobrunn för att ta om hand personer som inte vistats på kolerafri ort de 10 senaste dagarna. Staden delades in i tio distrikt som bemannades med en distriktschef samt några uppsyningsmän, som kontrollerade att staden hölls ren och att invånarna var rena. Stadens läkare var väldigt aktiva under sundhetsnämndens möten år 1834 och gav flera förslag på vad som behövdes göras medan de år 1853 intog en mer passiv roll. Åtgärderna i Stockholm år 1834 är snarlika de åtgärder som genomfördes i Falun samma år, huvudstaden delades också in i distrikt och det tillsattes även distriktschefer och uppsyningsmän. En annan likhet är att både Falun och Stockholm beställde färdiga likkistor för att ha i beredskap. Såväl sundhetsnämnderna i Karlskrona, Ystad och Arboga liksom Falun år 1853 vidtog i stort sett samma åtgärder som gjordes redan år 1834 t ex spärrningsåtgärder, karantänsskydd, införandet av kolerasjukhus och extra insatser för de mest utsatta i samhället.

On the problem of algebraic completeness for the invariants of the Riemann tensor. III.

We study the set CZ of invariants [Zakhary and Carminati, J. Math. Phys. 42, 1474 (2001)] for the class of space-times whose Ricci tensors possess a null eigenvector. We show that all cases are maximally backsolvable, in terms of sets of invariants from CZ, but that some cases are not completely backsolvable and these all possess an alignment between an eigenvector of the Ricci tensor with a repeated principal null vector of the Weyl tensor. We provide algebraically complete sets for each canonically different space-time and hence conclude with these results and those of a previous article [Carminati, Zakhary, and McLenaghan, J. Math. Phys. 43, 492 (2002)] that the CZ set is determining or maximal.

Avoiding the Fog of Crisis: A Protocol for the Proper Domestic Use of the Military

Failure to contemplate and define an appropriate role for the armed forces of the national government in domestic crises of this sort is a serious problem. It is all the more serious now as these potential crises seem to multiply in character and scope. This thesis will explore the history of this problem and its recent implications. It will argue the need for a comprehensive, operational framework, codified in law, which defines the various alternative uses of all emergency services, both civilian and military, and is applicable to “all hazards.” I will attempt to provide a blue-print for what such a framework should look like.

What drives long-distance movements in the nomadic Grey Teal Anas gracilis in Australia?

In contrast to northern temperate environments, where day length and temperature changes are obvious proximate cues for movement to resource-rich breeding habitats, the cues for movement used by birds in an often resource-poor, stochastic environment are less obvious. We recorded long-distance movements of 23 Grey Teal Anas gracilis using satellite telemetry for up to 879 days and examined the relationship between those movements and environmental factors, such as heavy rainfall and flooding, at the destination site. We identified 32 long-distance [> 150 km) movements that met our criterion for minimally interrupted flight between origin and destination. Thirteen of these flights coincided with rainfall and/or flooding events up to 1050 km from the origin. However, some ducks moved without any clear beneficial conditions at the destination onto small wetlands in regions with little surface water. The data suggest that there are two types of long-distance movement - ranging and directed. These flights occurred over distances up to 1200 km across the arid inland. The rates and distances of movement suggest that long-distance movements of Grey Teal entail high energy costs as in waterfowl elsewhere. We conclude that the proximate controls of directIn contrast to northern temperate environments, where day length and temperature changes are obvious proximate cues for movement to resource-rich breeding habitats, the cues for movement used by birds in an often resource-poor, stochastic environment are less obvious. We recorded long-distance movements of 23 Grey Teal Anas gracilis using satellite telemetry for up to 879 days and examined the relationship between those movements and environmental factors, such as heavy rainfall and flooding, at the destination site. We identified 32 long-distance (> 150 km) movements that met our criterion for minimally interrupted flight between origin and destination. Thirteen of these flights coincided with rainfall and/or flooding events up to 1050 km from the origin. However, some ducks moved without any clear beneficial conditions at the destination onto small wetlands in regions with little surface water. The data suggest that there are two types of long-distance movement – ranging and directed. These flights occurred over distances up to 1200 km across the arid inland. The rates and distances of movement suggest that long-distance movements of Grey Teal entail high energy costs as in waterfowl elsewhere. We conclude that the proximate controls of directed movements need not be very different from those of their temperate counterparts.ed movements need not be very different from those of their temperate counterparts.

On the problem of algebraic completeness for the invariants of the Riemann tensor. II

We study the set of invariants CZ [E. Zakhary and J. Carminati, J. Math. Phys. 42, 1474 (2001)] for the class of space-times whose Ricci tensors do not possess a null eigenvector. We show that all cases are completely backsolvable in terms of sets of invariants from CZ. We provide algebraically complete sets for each canonically different space-time.

Storage of stones by Jays Garrulus glandarius

The aims of this study were to test whether or not Jays Garrulus glandarius store stones and, if so, to examine the conditions under which they store stones. By directly observing the behaviour of five captive jays that were housed individually in flight cages, we found that stones were stored only in the absence of food items or when food items were no longer available to store and that there was a strong preference for storing stones that resembled acorns in both size and appearance (in terms of colour, shape and smoothness of the surface) and were undamaged rather than heavily chipped. These results are discussed in terms of Tinbergen's classic ethological model in which animals respond selectively to certain key features and ignore other features of the stimulus.

The functional significance of multiple nest-building in the Australian Reed Warbler Acrocephalus australis

The vast majority of bird species build a nest in which to breed. Some species build more than one nest, but the function of most multiple nest-building remains unclear. Here we describe the unusual nest-building behaviour of the Australian Reed Warbler Acrocephalus australis, and test experimentally the hypotheses that multiple nest-building is related to individual condition or territory quality, and plays a role in mate assessment. Australian Reed Warblers built two types of nest structures: 'type I' nests, which were used for eggs and nestlings, and 'type II' nests, which were structurally distinct from type I nests, did not support eggs, nestlings or adults and were not essential for successful breeding. The number of type II nests built in each territory varied. Type II nests were only built before breeding had commenced in a territory and females were not observed participating in their construction, supporting a role in female mate choice. Birds provided with supplementary food built significantly more type II nests than control birds. However, supplementary-fed birds did not have greater pairing success, and the addition of further type II nests to territories did not increase the pairing rate or type II nest construction in those territories. There was no relationship between the presence of type II nests and either reproductive success or likelihood of nest predation. We discuss the implications of these results in light of previous suggestions regarding the function of multiple nest-building in birds.