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This paper reports on the accuracy of new test methods developed to measure the air and water permeability of high-performance concretes (HPCs). Five representative HPC and one normal concrete (NC) mixtures were tested to estimate both repeatability and reliability of the proposed methods. Repeatability acceptance was adjudged using values of signal-noise ratio (SNR) and discrimination ratio (DR), and reliability was investigated by comparing against standard laboratory-based test methods (i.e., the RILEM gas permeability test and BS EN water penetration test). With SNR and DR values satisfying recommended criteria, it was concluded that test repeatability error has no significant influence on results. In addition, the research confirmed strong positive relationships between the proposed test methods and existing standard permeability assessment techniques. Based on these findings, the proposed test methods show strong potential to become recognized as international methods for determining the permeability of HPCs. [ABSTRACT FROM AUTHOR]

Objective: Anecdotal reports suggest that application of a cool device to the back of the neck at the onset of a hot flush can afford symptomatic relief. The effects of a novel handheld mechanical cooling device in a population of perimenopausal women with moderate-to-severe vasomotor symptoms were evaluated.Methods: In this randomized, double-blind, sham-controlled pilot study, 40 perimenopausal women experiencing ≥ 7 moderate-to-severe hot flushes per day were recruited at a single university site. Women were randomized to the active (n = 20) or sham (n = 20) device, which was applied to the back of the neck with each hot flush over the 4-week treatment period. Hot flush scores were calculated based on frequency and severity of symptoms. The Carpenter Hot Flash Related Daily Interference Scale and Zung Anxiety Scale were used to evaluate impact on quality of life. At study end, participants completed an open-ended questionnaire to assess the degree of unblinding and overall subjective improvement in symptoms with use of the device.Results: No statistically significant differences were observed between the effects of the active and sham device. However, thematic analysis of the open-ended questionnaire revealed that 12/17 women (70.6%) in the active group, compared to 4/18 (22.2%) women in the sham group felt the device provided some symptomatic relief.Conclusions: Although the majority of women using the active device acknowledged that its cooling effect afforded a degree of symptomatic relief, the symptom scores chosen for this pilot study did not reflect a beneficial effect. [ABSTRACT FROM AUTHOR]

Cassini Ion Neutral Mass Spectrometer (INMS) measurements from roughly a hundred Titan encounters over the Cassini mission yield neutral and ion densities systematically lower, by factors approximately 2 to 3, than estimates from several other spacecraft systems, including the Attitude and Articulation Control System, and Navigation system. In this paper we present a new INMS instrument sensitivity model, obtained by re-analyzing (1) the capture and transmission of neutral gas through the instrument, and (2) the detector gain reduction during pre-launch testing. By correcting for an under-estimation of gas leakage out of the instrument into space by the original calibration model, and adjusting for the gain change, the new model brings INMS densities into much closer agreement with the other Cassini systems. Accordingly, the INMS ion densities are revised upward by a constant detector sensitivity correction factor of 1.55±21 %, while the neutral sensitivities have a complex instrument pointing direction dependence, due (mostly) to the effect of the INMS vent and antechamber-to-closed source tube. In the special case of on-ram pointing the neutral densities are revised upward by a constant factor of 2.2±23 %. The corrected neutral and ion sensitivities given here are applicable to all previously published INMS results at Titan, Enceladus and elsewhere in the Saturn system. The new model gives reliable densities at high ram angles, in some cases above 90 degrees, thereby expanding the list of Titan flybys from which INMS densities may be extracted. We apply the model to obtain accurate densities from several off-ram Titan flybys which gave unusual neutral density vs. altitude profiles, or unreasonably high densities, with the original calibration. [ABSTRACT FROM AUTHOR]

The non-destructive evaluation of the water permeability of concrete structures is a long standing challenge, principally due to the difficulty of achieving a uni-direction flow for computing the water permeability coefficient. The use of a guard ring (GR) was originally proposed for the in situ sorptivity test, but little information can be found for the water permeability test. In this study, the effect of a GR was carefully examined through the flow simulation, which was verified by carrying out experiments. It was observed that the GR can confine the flow near the surface, but cannot achieve a uni-directional flow across the whole depth of flow. To achieve a better performance, it is essential to consider the effects of the size of the inner seal and the GR and the significant interaction between these two. The analysis of the experimental data has indicated that the GR influences the flow for porous concretes, but there is no significant effect for dense concretes. Further investigation, validated using the flow-net theory, has shown a strong correlation between the water permeability coefficients obtained with the GR ( K) and without it ( K), suggesting that one dimensional flow is not essential for interpreting data for site tests. Another practical issue was that more than 30 % of the tests with GR failed due to the difficulty of achieving a good seal between the inner and the outer chambers. Based on the work reported in this paper, a new water permeability test is proposed. [ABSTRACT FROM AUTHOR]

Jets of water ice from surface fractures near the south pole of Saturn’s icy moon Enceladus produce a plume of gas and particles. The source of the jets may be a liquid water region under the ice shell—as suggested most recently by the discovery of salts in E-ring particles derived from the plume—or warm ice that is heated, causing dissociation of clathrate hydrates. Here we report that ammonia is present in the plume, along with various organic compounds, deuterium and, very probably, 40Ar. The presence of ammonia provides strong evidence for the existence of at least some liquid water, given that temperatures in excess of 180 K have been measured near the fractures from which the jets emanate. We conclude, from the overall composition of the material, that the plume derives from both a liquid reservoir (or from ice that in recent geological time has been in contact with such a reservoir) as well as from degassing, volatile-charged ice. [ABSTRACT FROM AUTHOR]

Ion-neutral chemistry in Titan's upper atmosphere (~ 1000 km altitude) is an unexpectedly prodigious source of hydrocarbon-nitrile compounds. We report observations from the Cassini Ion Neutral Mass Spectrometer (INMS; Waite et al. 2004) and Cassini Plasma Spectrometer (CAPS; Young et al. 2004) that allow us to follow the formation of the organic material from the initial ionization and dissociation of nitrogen and methane driven by several free energy sources (extreme ultraviolet radiation and energetic ions and electrons) to the formation of negative ions with masses exceeding 10,000 amu. [ABSTRACT FROM PUBLISHER]

Trastuzumab is an effective treatment for patients with metastatic breast cancer (MBC) that overexpresses HER-2. A high incidence of brain metastases (BM) has been noted in patients receiving trastuzumab. A retrospective chart review was conducted of 100 patients commencing trastuzumab for metastatic breast cancer from July 1999 to December 2002, at the Christie Hospital. Seven patients were excluded; five patients developed central nervous system metastases prior to starting trastuzumab, and inadequate data were available for two. Out of the remaining 93 patients, 23 (25%) have developed BM to date. In all, 46 patients have died, and of these 18 (39%) have been diagnosed with BM prior to death. Of the 23 patients developing BM, 18 (78%) were hormone receptor negative and 18 (78%) had visceral disease. Univariate analysis showed a significant association between the development of cerebral disease and both hormone receptor status and the presence of visceral disease. In conclusion, a high proportion of patients with MBC treated with trastuzumab develop symptomatic cerebral metastases. HER-2-positive breast cancer may have a predilection for the brain, or trastuzumab therapy may change the disease pattern by prolonging survival. New strategies to address this problem require investigation in this group of patients. [ABSTRACT FROM AUTHOR]

We present the diploid genome sequence of the fungal pathogen Candida albicans. Because C. albicans has no known haploid or homozygous form, sequencing was performed as a whole-genome shotgun of the heterozygous diploid genome in strain SC5314, a clinical isolate that is the parent of strains widely used for molecular analysis. We developed computational methods to assemble a diploid genome sequence in good agreement with available physical mapping data. We provide a whole-genome description of heterozygosity in the organism. Comparative genomic analyses provide important clues about the evolution of the species and its mechanisms of pathogenesis. [ABSTRACT FROM AUTHOR]

Purpose: To investigate whether transforming growth factor beta-1 (TGFβ1) single nucleotide polymorphisms were associated with the susceptibility of breast cancer patients to severe radiationinduced normal tissue damage. Materials and methods: PCR-RFLP assays were performed for TGFβ1 gene polymorphisms on DNA obtained from 103 breast cancer patients who received radiotherapy. The G-800A, C-509T, T + 869C and G + 915C polymorphic sites were examined, and genotype and allele frequencies of two subgroups of patients were calculated and compared. Results: The less prevalent -509T and +869C alleles were significantly associated with a subgroup of patients who developed severe radiation-induced normal tissue fibrosis (n = 15) when compared with those who did not (n = 88) (odds ratio = 3.4, p = 0.0036, and 2.37, p = 0.035, respectively). Furthermore, patients with the -509TT or +869CC genotypes were between seven and 15 times more likely to develop severe fibrosis. Conclusions: These findings imply a role for the -509T and +869C alleles in the pathobiological mechanisms underlying susceptibility to radiation-induced fibrosis. Their predictive value would be limited to patients who are -509TT or +869CC, but if 'fibrosis-associated' polymorphic sites in other genes could be identified, it may be possible to detect fibrosis prone individuals before radiotherapy with greater certainty. [ABSTRACT FROM AUTHOR]

Summary Candida albicans is the single, most frequently isolated human fungal pathogen. As with most fungal pathogens, the factors which contribute to pathogenesis in C. albicans are not known, despite more than a decade of molecular genetic analysis. Candida albicans was thought to be asexual until the discovery of the MTL loci homologous to the mating type (MAT ) loci in Saccharomyces cerevisiae led to the demonstration that mating is possible. Using Candida albicans mutants in genes likely to be involved in mating, we analysed the process to determine its similarity to mating in Saccharomyces cerevisiae . We examined disruptions of three of the genes in the MAPK pathway which is involved in filamentous growth in both S. cerevisiae and C. albicans and is known to control pheromone response in the former fungus. Disruptions in HST7 and CPH1 blocked mating in both MTL a and MTL α strains, whereas disruptions in STE20 had no effect. A disruption in KEX2 , a gene involved in processing the S. cerevisiae pheromone Mfα, prevented mating in MTL α but not MTL a cells, whereas a disruption in HST6, the orthologue of the STE6 gene which encodes an ABC transporter responsible for secretion of the Mfa pheromone, prevented mating in MTL a but not in MTL α cells. Disruption of two cell wall genes, ALS1 and INT1 , had no effect on mating, even though ALS1 was identified by similarity to the S. cerevisiae sexual agglutinin, SAG1 . The results reveal that these two diverged yeasts show a surprising similarity in their mating processes. [ABSTRACT FROM AUTHOR]

A correction to the article "Liquid water on Enceladus from observations of ammonia and 40Ar in the plume" that was published in the previous issue is presented.

A letter to the editor is presented in response to the article "Combined Screening With Ultrasound and Mammography vs Mammography Alone in Women at Elevated Risk of Breast Cancer," by Dr. W.A. Berg and colleagues in a previous 2008 issue.