Violation of critical universality at the antiferromagnetic phase transition of YbRh2Si2

We report on precise low-temperature specific-heat measurements, C(T), of YbRh2Si2 in the vicinity of the antiferromagnetic phase transition on a single crystal of superior quality (RRR 150). We observe a very sharp peak at T_N=72mK with absolute values as high as C/T=8J/molK^2. A detailed analysis of the critical exponent \alpha around T_N reveals \alpha=0.38 which differs significantly from those of the conventional universality classes in the Ginzburg-Landau theory, where \alpha<0.11. Thermal-expansion measurements corroborate this large positive critical exponent. These results provide insight into the nature of the critical magnetic fluctuations at a temperature-driven phase transition close to a quantum critical point.Comment: Accepted for PR

Evidence of continued transmission of Wuchereria bancrofti and associated factors despite nine rounds of ivermectin and albendazole mass drug administration in Rufiji district, Tanzania

Background: In most sub-Saharan Africa, the National Lymphatic Filariasis Elimination Programme (NLFEP) is based on annual mass drug administration (MDA) with ivermectin and albendazole. In order to interrupt transmission, 4–6 rounds of MDA are required with at least 60–70% minimum effective coverage. Children born since the introduction of the MDA programme are recommended for assessing the interruption of transmission. The objective of this study was lymphatic filariasis transmission status after nine rounds of MDA in Rufiji district, Tanzania.Methods: This cross sectional survey involved 270 heads of household. Parents or guardians were interviewed on behalf of the schoolchildren about their participation in MDA programme. Status of LF prevalence was assessed by measuring Wuchereria bancrofti circulating filarial antigens (CFA) in blood samples from standard one school children (6 – 9 years)   using immunochromatographic test cards.Results: A total of 413 standard one schoolchildren were tested for CFA; 59 (14.3%) had CFA. Two thirds (66.8%) of the children did not participate in 2011 MDA round. Prevalence of CFA was significantly lower in younger (6.4%) than older children (40.4%) (p&lt;0.05). Participation in the last (2011) MDA did not significantly change the prevalence W. bancrofti CFA (χ2 = 0.723, p=0.4). The recorded MDA coverage for 5 years including 2011 was above the 60–70 % minimum effective coverage. The community reported coverage was 40.4% for last MDA (2011), for previous MDAs was 53.0%; being far below the minimum effective coverage. Though the large majority (97.0%) of households had heard of LF, only about half (57.0%) knew it was transmitted by mosquitoes. Less than a half (43.6%) of households were aware of the adverse effects of LF, therefore motivated to participate in MDA.Conclusion: The findings indicate that LF transmission has continued in Rufiji district despite nine rounds of MDA. Low compliance to MDAs due to community and programmatic factors were responsible for the continued LF transmission. Detailed entomological studies are required to establish LF transmission dynamics and the programmatic factors associated with MDA implementation in the area

Finding a state in a haystack

We consider the problem to single out a particular state among $2^n$ orthogonal pure states. As it turns out, in general the optimal strategy is not to measure the particles separately, but to consider joint properties of the $n$-particle system. The required number of propositions is $n$. There exist $2^n!$ equivalent operational procedures to do so. We enumerate some configurations for three particles, in particular the Greenberger-Horne-Zeilinger (GHZ)- and W-states, which are specific cases of a unitary transformation For the GHZ-case, an explicit physical meaning of the projection operators is discussed.Comment: 11 page

Electronic newsstand : design of an intelligent interface to a variety of news sources in several media

Thesis (M.S.V.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1986.MICROFICHE COPY AVAILABLE IN ARCHIVES AND ROTCH.Includes bibliographical references (leaves 58-63).The personal computer. as an intermediary between mass communications systems and the individual viewer, can filter incoming news, eliminating irrelevant and redundant stories and highlighting items of interest. However, important information can be lost by removing an article from the context of its original publication. Knowing the identity of the source helps the viewer judge the reliability and objectivity of the account. Seeing the article as originally presented among a number of other stories indicates to the viewer the significance of the story and its relationship to other current events. A program has been designed and implemented which presents news articles within the context of their original publication. It provides a uniform interface to a number of electronically distributed publications, both text and video. A two level display accommodates both casual browsing and attentive viewing. The first level, which shows several articles simultaneously , preserves the information encoded in the original layout. The second level. which displays a single article, is designed to provide the best environment for viewing that article. The program can be used to create special interest compilations. Topics of interest may be defined by marking keywords. All available sources are searched for pertinent articles. These are collected in a "synthetic" journal. The same interface is used to peruse ·an original publication and a user-specified synthetic journal.by Judith S. Donath.M.S.V.S

miR-30 Regulates Mitochondrial Fission through Targeting p53 and the Dynamin-Related Protein-1 Pathway

miRNAs participate in the regulation of apoptosis. However, it remains largely unknown as to how miRNAs are integrated into the apoptotic program. Mitochondrial fission is involved in the initiation of apoptosis. It is not yet clear whether miRNAs are able to regulate mitochondrial fission. Here we report that miR-30 family members are able to regulate apoptosis by targeting the mitochondrial fission machinery. Our data show that miR-30 family members can inhibit mitochondrial fission and the consequent apoptosis. In exploring the underlying molecular mechanism, we identified that miR-30 family members can suppress p53 expression. In response to the apoptotic stimulation, the expression levels of miR-30 family members were reduced, whereas p53 was upregulated. p53 transcriptionally activated the mitochondrial fission protein, dynamin-related protein-1 (Drp1). The latter conveyed the apoptotic signal of p53 by initiating the mitochondrial fission program. miR-30 family members inhibited mitochondrial fission through suppressing the expression of p53 and its downstream target Drp1. Our data reveal a novel model in which a miRNA can regulate apoptosis through targeting the mitochondrial fission machinery

A tilted grating interferometer for full vector field differential x-ray phase contrast tomography

We report on a setup for differential x-ray phase-contrast imaging and tomography, that measures the full 2D phase-gradient information. The setup uses a simple one-dimensional x-ray grating interferometer, in which the grating structures of the interferometer are oriented at a tilt angle with respect to the sample rotation axis. In such a configuration, the differential phase images from opposing tomography projections can be combined to yield both components of the gradient vector. We show how the refractive index distribution as well as its x, y, and z gradient components can be reconstructed directly from the recorded projection data. The method can equally well be applied at conventional x-ray tube sources, to analyzer based x-ray imaging or neutron imaging. It is demonstrated with measurements of an x-ray phantom and a rat brain using synchrotron radiation

Trolling in asynchronous computer-mediated communication: From user discussions to academic definitions

Whilst computer-mediated communication (CMC) can benefit users by providing quick and easy communication between those separated by time and space, it can also provide varying degrees of anonymity that may encourage a sense of impunity and freedom from being held accountable for inappropriate online behaviour. As such, CMC is a fertile ground for studying impoliteness, whether it occurs in response to perceived threat (flaming), or as an end in its own right (trolling). Currently, first and secondorder definitions of terms such as im/politeness (Brown and Levinson 1987; Bousfield 2008; Culpeper 2008; Terkourafi 2008), in-civility (Lakoff 2005), rudeness (Beebe 1995, Kienpointner 1997, 2008), and etiquette (Coulmas 1992), are subject to much discussion and debate, yet the CMC phenomenon of trolling is not adequately captured by any of these terms. Following Bousfield (in press), Culpeper (2010) and others, this paper suggests that a definition of trolling should be informed first and foremost by user discussions. Taking examples from a 172-million-word, asynchronous CMC corpus, four interrelated conditions of aggression, deception, disruption, and success are discussed. Finally, a working definition of trolling is presented