Reply to "Comment on `Quenches in quantum many-body systems: One-dimensional Bose-Hubbard model reexamined' ''

In his Comment [see preceding Comment, Phys. Rev. A 82, 037601 (2010)] on the paper by Roux [Phys. Rev. A 79, 021608(R) (2009)], Rigol argued that the energy distribution after a quench is not related to standard statistical ensembles and cannot explain thermalization. The latter is proposed to stem from what he calls the eigenstate thermalization hypothesis and which boils down to the fact that simple observables are expected to be smooth functions of the energy. In this Reply, we show that there is no contradiction or confusion between the observations and discussions of Roux and the expected thermalization scenario discussed by Rigol. In addition, we emphasize a few other important aspects, in particular the definition of temperature and the equivalence of ensemble, which are much more difficult to show numerically even though we believe they are essential to the discussion of thermalization. These remarks could be of interest to people interested in the interpretation of the data obtained on finite-size systems.Comment: 3 page

Fast inactivation in Shaker K+ channels. Properties of ionic and gating currents.

Fast inactivating Shaker H4 potassium channels and nonconducting pore mutant Shaker H4 W434F channels have been used to correlate the installation and recovery of the fast inactivation of ionic current with changes in the kinetics of gating current known as "charge immobilization" (Armstrong, C.M., and F. Bezanilla. 1977. J. Gen. Physiol. 70:567-590.). Shaker H4 W434F gating currents are very similar to those of the conducting clone recorded in potassium-free solutions. This mutant channel allows the recording of the total gating charge return, even when returning from potentials that would largely inactivate conducting channels. As the depolarizing potential increased, the OFF gating currents decay phase at -90 mV return potential changed from a single fast component to at least two components, the slower requiring approximately 200 ms for a full charge return. The charge immobilization onset and the ionic current decay have an identical time course. The recoveries of gating current (Shaker H4 W434F) and ionic current (Shaker H4) in 2 mM external potassium have at least two components. Both recoveries are similar at -120 and -90 mV. In contrast, at higher potentials (-70 and -50 mV), the gating charge recovers significantly more slowly than the ionic current. A model with a single inactivated state cannot account for all our data, which strongly support the existence of "parallel" inactivated states. In this model, a fraction of the charge can be recovered upon repolarization while the channel pore is occupied by the NH2-terminus region

The impact of emigration on population estimates of deep-sea red crab Chaceon maritae off Namibia

Underwater photography and tag-recapture methods have previously been found to be the most accurate means of assessing the size of the population of Chaceon maritae off southern Africa. However, recent population estimates made by the tag-recapture method appear to be too high. Sources of bias in the estimate that led to violations of assumptions of the Petersen method were investigated. Females migrate into Angola and tend to travel farther than males. Population estimates that used information for males only or that accounted for emigration to Angolan waters are therefore too high. Another source of bias included under-reporting of tag recaptures in 1993.Keywords: emigration, population estimate, red crab, tag-recapture African Journal of Marine Science 2001, 23: 61–6

A study of local government HIV/AIDS projects in South Africa

The primary goal of this study was to survey local government HIV/AIDS projects in South Africa.A total of 240 questionnaires were sent to local municipalities nationally between May and July 2002.A total of 44 municipalities returned their questionnaires, covering 53 projects. Most projects focused on prevention and awareness and the majority had awareness/prevention/information as part of their objectives as well as their activities. Home/community-based care was also prominent. It seems that in the future the focus of programme development will shift in this direction. Major constraints were a lack of funds, transport and trained personnel. Future emphasis must thus be put on these components. In addition government needs to put more resources into local government HIV/AIDS programmes since this tier will be the nodal point for national combatting of the HIV/AIDS epidemic. SAHARA-J (2004) 1(2): 99-106 Keywords: local government, HIV/AIDS, home/community-based care, Department of Social Development. RÉSUMÉ Le but principal de cette étude fut de sonder des projets du VIH/SIDA dans le gouvernement local en Afrique du Sud. Deux cents quarante questionnaires ont été envoyés aux municipalités locales du pays à partir du mois de mai jusqu'au mois de juillet 2002. Au total, 44 municipalités ont renvoyé leurs questionnaires. Ce derniers couvrent 53 projets. La plupart de projets se sont concentrés sur la prévention et la prise de conscience alors que la majorité de projets incluent la prise de conscience, la prévention et l'information parmi leurs objectif et leurs activités. Les soins à domicile ou dans la communauté étaient également saillants. Il semble que dans l'avenir le développement de programme se focalisera vers cette direction. Les contraintes majeures furent le manque de fonds, du transport et du personnel qualifié. De ce fait, dans l'avenir l'accent doit être mis sur ces facteurs. De plus, le gouvernement doit procurer davantage des ressources pour les programmes du VIH/SIDA au gouvernement local vu que cette étape sera le centre d'intérêt vis-à-vis le combat national contre l'épidémie du VIH/SIDA. SAHARA-J (2004) 1(2): 99-106 Mots clés: le gouvernement local, le VIH/SIDA, les soins à domicile ou dans la communauté, le Département de Développement Social

Characteristics of Wetting-Induced Bacteriophage Blooms in Biological Soil Crust.

Biological soil crusts (biocrusts) are photosynthetic "hot spots" in deserts and cover ∼12% of the Earth's terrestrial surface, and yet they face an uncertain future given expected shifts in rainfall events. Laboratory wetting of biocrust communities is known to cause a bloom of Firmicutes which rapidly become dominant community members within 2 days after emerging from a sporulated state. We hypothesized that their bacteriophages (phages) would respond to such a dramatic increase in their host's abundance. In our experiment, wetting caused Firmicutes to bloom and triggered a significant depletion of cyanobacterial diversity. We used genome-resolved metagenomics to link phage to their hosts and found that the bloom of the genus Bacillus correlated with a dramatic increase in the number of Caudovirales phages targeting these diverse spore-formers (r = 0.762). After 2 days, we observed dramatic reductions in the relative abundances of Bacillus, while the number of Bacillus phages continued to increase, suggestive of a predator-prey relationship. We found predicted auxiliary metabolic genes (AMGs) associated with sporulation in several Caudovirales genomes, suggesting that phages may influence and even benefit from sporulation dynamics in biocrusts. Prophage elements and CRISPR-Cas repeats in Firmicutes metagenome-assembled genomes (MAGs) provide evidence of recent infection events by phages, which were corroborated by mapping viral contigs to their host MAGs. Combined, these findings suggest that the blooming Firmicutes become primary targets for biocrust Caudovirales phages, consistent with the classical "kill-the-winner" hypothesis.IMPORTANCE This work forms part of an overarching research theme studying the effects of a changing climate on biological soil crust (biocrust) in the Southwestern United States. To our knowledge, this study was the first to characterize bacteriophages in biocrust and offers a view into the ecology of phages in response to a laboratory wetting experiment. The phages identified here represent lineages of Caudovirales, and we found that the dynamics of their interactions with their Firmicutes hosts explain the collapse of a bacterial bloom that was induced by wetting. Moreover, we show that phages carried host-altering metabolic genes and found evidence of proviral infection and CRISPR-Cas repeats within host genomes. Our results suggest that phages exert controls on population density by lysing dominant bacterial hosts and that they further impact biocrust by acquiring host genes for sporulation. Future research should explore how dominant these phages are in other biocrust communities and quantify how much the control and lysis of blooming populations contributes to nutrient cycling in biocrusts

Cointegration between energy commodities and the South African financial market

Abstract: The long-run relationship between three energy commodities, namely crude oil, jet kerosene and natural gas; and the FTSE/JSE Top 40 Index will be examined. A second relationship between the three commodities and the FTSE/JSE Top 40 Index against the South African Rand (versus the United States Dollar) will also be explored to determine the impact of the variables on the ZAR. The analysis of the variables will include correlation, regression, vector autoregression and the Johansen cointegration test to determine linear interdependencies among the variables. The results indicate that there is a cointegrating relationship between the both relationships investigated