Possibility of Using a Satellite-Based Detector for Recording Cherenkov Light from Ultrahigh-Energy Extensive Air Showers Penetrating into the Ocean Water

We have estimated the reflected component of Cherenkov radiation, which arises in developing of an extensive air shower with primary energy of 10^20 eV over the ocean surface. It has been shown that, under conditions of the TUS experiment, a flash of the reflected Cherenkov photons at the end of the fluorescence track can be identified in showers with zenith angles up to 20 degrees.Comment: 5 pages, 3 figures. This preprint corrects errors which appeared in the English version of the article published in Bull. Rus. Acad. Sci. Phys., 2011, Vol. 75, No. 3, p. 381. The original russian text was published in Izv. RAN. Ser. Fiz., 2011, Vol. 75, No. 3, p. 41

Complementary vertices and adjacency testing in polytopes

Our main theoretical result is that, if a simple polytope has a pair of complementary vertices (i.e., two vertices with no facets in common), then it has at least two such pairs, which can be chosen to be disjoint. Using this result, we improve adjacency testing for vertices in both simple and non-simple polytopes: given a polytope in the standard form {x \in R^n | Ax = b and x \geq 0} and a list of its V vertices, we describe an O(n) test to identify whether any two given vertices are adjacent. For simple polytopes this test is perfect; for non-simple polytopes it may be indeterminate, and instead acts as a filter to identify non-adjacent pairs. Our test requires an O(n^2 V + n V^2) precomputation, which is acceptable in settings such as all-pairs adjacency testing. These results improve upon the more general O(nV) combinatorial and O(n^3) algebraic adjacency tests from the literature.Comment: 14 pages, 5 figures. v1: published in COCOON 2012. v2: full journal version, which strengthens and extends the results in Section 2 (see p1 of the paper for details

The Impact of Human Immunodeficiency Virus and Human Papillomavirus Co-Infection on HPV Genotype Distribution and Cervical Lesion Grade in a Semi-Urban Population in Tigoni, Kenya

1. IntroductionCervical cancer is an important global public healthproblem and a common cause of death among women,and it is attributable to human papillomavirus (HPV)(Walboomers et al, 1999; Parkin et al, 2008). In a largeseries of invasive cervical cancer from around theworld, HPV-DNA was detected in 99.7% of the tumors,leading to the conclusion that HPV was a necessarycause of cervical cancer (Bosch et al, 1995; Walboomerset al, 1999; Bosch et al, 2007). The identification ofHPV’s role in cervical cancer has led to importantadvances in primary prevention through vaccinationand diagnosis through HPV detection (Stanley et al,2008; Bosch et al, 2008). However, tangible reductionin the incidence of cervical cancer and the impact onglobal public health will probably take decades. As HPVtypes are divergent, efficacy of current vaccines is typerestricted,and therefore development of the nextgeneration of HPV vaccines will require inclusion ofrelevant antigens from several HPV types (Lowy, 2008).Geographical profiling of HPV type distribution will beimportant in making vaccines more relevant for targetpopulations.Most women will be infected with HPV sometime intheir lifetime. Results from large meta-analyses studiesindicate that at any given point in time, 10.4% (95%confidence interval (CI) 10.2-10.7) of womenworldwide are positive for cervical HPV DNA (Bosch etal, 2008). The prevalence of HPV is higher in lessdeveloped regions (13.4%; 95% CI: 13.1-13.7) than inthe more developed regions (8.4%; 95% CI: 8.3-8.6)(Bosch et al, 2008). The same studies indicate thatAfrican women at 22.1% (95% CI: 20.9-23.4) and EastAfrican women in particular, have the highest HPVprevalence rates (31.6%; 95% CI: 29.5-33.8) (Bosch etal, 2008). HPV type 16 is the most common in allcontinents, with an estimated point prevalence of 2.6%(95% CI: 2.5-2.8) worldwide, and HPV type 18 thesecond most frequently detected type (Clifford et al,2005). Regional differences are thought to be related togeographical and immunogenetic factors, such asdefects in cellular immunity through chronic cervicalinflammation, malnutrition and more recently, HIVinfection; Type 16 though appears to be less influencedby immune impairment than other types (Clifford et al,2005).Although many women get infected with HPV, most donot develop cervical cancer. Several co-factors arepostulated to influence the disease process. Thepotential co-factors include exogenous factors such astobacco smoking, hormonal contraceptives, and coinfectionswith other sexually transmitted infections(Munoz et al, 2006). In addition, viral co-factors, suchspecific HPV types, viral load, and viral integration, aswell as host co-factors such as endogenous hormones,genetic factors, and factors related to the immuneresponse may variably influence the course of HPVinfection (Munoz et al, 2006).Women with HIV infection have been shown to be morelikely not only to have a concurrent HPV infection butalso to have an increased risk for a high grade cervicalsquamous intraepithelial lesion (La Ruche et al, 1998;Temmerman et al, 1999; Womack et al, 2000; Baay et al,2004; Hawes et al, 2006; Didelot-Rousseau et al, 2006;Ngándwe et al, 2007). HPV is the commonest sexuallytransmitted infection, with more than 75% of sexuallyactive adults acquiring one or more genotypes in theirlifetime (Bosch et al, 2008). However, by age 30 years,most women clear the infection due to an effective cellmediatedimmune response, and only a small numberthereafter are diagnosed with a HPV-associated lesion(Schiffman, 1992). It is thought that it is through itseffect on CD4+ cells and regulation of immuneresponses to a variety of antigens that HIV attenuatesthe systemic response to HPV (Palefsky, 2006).The prevalence of HIV among adult Kenyan women was13% in 2003 with trends reported to have decreased to5.1% by 2006 (KDHS, 2003). The high prevalence ofHIV may increase the incidence of cervical pre-cancerand potentially, of cervical cancer. Gichangi et al (2002),however, demonstrated that a two to three-foldincrease in HIV prevalence did not translate to aproportionate increment in incidence of cervical cancer.They hypothesized that HIV-infected women die fromHIV-related opportunistic infections before theydevelop invasive cervical cancer. The mean survivaltime for women with HIV in 2008 was reported to be 5years (Yamada et al, 2008) while typically more than 10years elapse before the development of cervical cancerafter HPV infection. Yamada et al (2008) also advancedthe possibility that sub-clinical cervical cancer may bemissed in many women dying prematurely from AIDSrelatedopportunistic infections.This study was carried out to establish whether the coinfectionof HIV and HPV has an influence on HPVgenotype distribution and on the prevalence and gradeof cervical neoplasia

The Impact of Human Immunodeficiency Virus and Human Papillomavirus Co-Infection on HPV Genotype Distribution and Cervical Lesion Grade in a Semi-Urban Population in Tigoni, Kenya

1. IntroductionCervical cancer is an important global public healthproblem and a common cause of death among women,and it is attributable to human papillomavirus (HPV)(Walboomers et al, 1999; Parkin et al, 2008). In a largeseries of invasive cervical cancer from around theworld, HPV-DNA was detected in 99.7% of the tumors,leading to the conclusion that HPV was a necessarycause of cervical cancer (Bosch et al, 1995; Walboomerset al, 1999; Bosch et al, 2007). The identification ofHPV’s role in cervical cancer has led to importantadvances in primary prevention through vaccinationand diagnosis through HPV detection (Stanley et al,2008; Bosch et al, 2008). However, tangible reductionin the incidence of cervical cancer and the impact onglobal public health will probably take decades. As HPVtypes are divergent, efficacy of current vaccines is typerestricted,and therefore development of the nextgeneration of HPV vaccines will require inclusion ofrelevant antigens from several HPV types (Lowy, 2008).Geographical profiling of HPV type distribution will beimportant in making vaccines more relevant for targetpopulations.Most women will be infected with HPV sometime intheir lifetime. Results from large meta-analyses studiesindicate that at any given point in time, 10.4% (95%confidence interval (CI) 10.2-10.7) of womenworldwide are positive for cervical HPV DNA (Bosch etal, 2008). The prevalence of HPV is higher in lessdeveloped regions (13.4%; 95% CI: 13.1-13.7) than inthe more developed regions (8.4%; 95% CI: 8.3-8.6)(Bosch et al, 2008). The same studies indicate thatAfrican women at 22.1% (95% CI: 20.9-23.4) and EastAfrican women in particular, have the highest HPVprevalence rates (31.6%; 95% CI: 29.5-33.8) (Bosch etal, 2008). HPV type 16 is the most common in allcontinents, with an estimated point prevalence of 2.6%(95% CI: 2.5-2.8) worldwide, and HPV type 18 thesecond most frequently detected type (Clifford et al,2005). Regional differences are thought to be related togeographical and immunogenetic factors, such asdefects in cellular immunity through chronic cervicalinflammation, malnutrition and more recently, HIVinfection; Type 16 though appears to be less influencedby immune impairment than other types (Clifford et al,2005).Although many women get infected with HPV, most donot develop cervical cancer. Several co-factors arepostulated to influence the disease process. Thepotential co-factors include exogenous factors such astobacco smoking, hormonal contraceptives, and coinfectionswith other sexually transmitted infections(Munoz et al, 2006). In addition, viral co-factors, suchspecific HPV types, viral load, and viral integration, aswell as host co-factors such as endogenous hormones,genetic factors, and factors related to the immuneresponse may variably influence the course of HPVinfection (Munoz et al, 2006).Women with HIV infection have been shown to be morelikely not only to have a concurrent HPV infection butalso to have an increased risk for a high grade cervicalsquamous intraepithelial lesion (La Ruche et al, 1998;Temmerman et al, 1999; Womack et al, 2000; Baay et al,2004; Hawes et al, 2006; Didelot-Rousseau et al, 2006;Ngándwe et al, 2007). HPV is the commonest sexuallytransmitted infection, with more than 75% of sexuallyactive adults acquiring one or more genotypes in theirlifetime (Bosch et al, 2008). However, by age 30 years,most women clear the infection due to an effective cellmediatedimmune response, and only a small numberthereafter are diagnosed with a HPV-associated lesion(Schiffman, 1992). It is thought that it is through itseffect on CD4+ cells and regulation of immuneresponses to a variety of antigens that HIV attenuatesthe systemic response to HPV (Palefsky, 2006).The prevalence of HIV among adult Kenyan women was13% in 2003 with trends reported to have decreased to5.1% by 2006 (KDHS, 2003). The high prevalence ofHIV may increase the incidence of cervical pre-cancerand potentially, of cervical cancer. Gichangi et al (2002),however, demonstrated that a two to three-foldincrease in HIV prevalence did not translate to aproportionate increment in incidence of cervical cancer.They hypothesized that HIV-infected women die fromHIV-related opportunistic infections before theydevelop invasive cervical cancer. The mean survivaltime for women with HIV in 2008 was reported to be 5years (Yamada et al, 2008) while typically more than 10years elapse before the development of cervical cancerafter HPV infection. Yamada et al (2008) also advancedthe possibility that sub-clinical cervical cancer may bemissed in many women dying prematurely from AIDSrelatedopportunistic infections.This study was carried out to establish whether the coinfectionof HIV and HPV has an influence on HPVgenotype distribution and on the prevalence and gradeof cervical neoplasia

Inflation Physics from the Cosmic Microwave Background and Large Scale Structure

Fluctuations in the intensity and polarization of the cosmic microwave background (CMB) and the large-scale distribution of matter in the universe each contain clues about the nature of the earliest moments of time. The next generation of CMB and large-scale structure (LSS) experiments are poised to test the leading paradigm for these earliest moments---the theory of cosmic inflation---and to detect the imprints of the inflationary epoch, thereby dramatically increasing our understanding of fundamental physics and the early universe. A future CMB experiment with sufficient angular resolution and frequency coverage that surveys at least 1 of the sky to a depth of 1 uK-arcmin can deliver a constraint on the tensor-to-scalar ratio that will either result in a 5-sigma measurement of the energy scale of inflation or rule out all large-field inflation models, even in the presence of foregrounds and the gravitational lensing B-mode signal. LSS experiments, particularly spectroscopic surveys such as the Dark Energy Spectroscopic Instrument, will complement the CMB effort by improving current constraints on running of the spectral index by up to a factor of four, improving constraints on curvature by a factor of ten, and providing non-Gaussianity constraints that are competitive with the current CMB bounds

The delivery of personalised, precision medicines via synthetic proteins

Introduction: The design of advanced drug delivery systems based on synthetic and su-pramolecular chemistry has been very successful. Liposomal doxorubicin (Caelyx®), and liposomal daunorubicin (DaunoXome®), estradiol topical emulsion (EstrasorbTM) as well as soluble or erodible polymer systems such as pegaspargase (Oncaspar®) or goserelin acetate (Zoladex®) represent considerable achievements. The Problem: As deliverables have evolved from low molecular weight drugs to biologics (currently representing approximately 30% of the market), so too have the demands made of advanced drug delivery technology. In parallel, the field of membrane trafficking (and endocytosis) has also matured. The trafficking of specific receptors i.e. material to be recycled or destroyed, as well as the trafficking of protein toxins has been well characterized. This, in conjunction with an ability to engineer synthetic, recombinant proteins provides several possibilities. The Solution: The first is using recombinant proteins as drugs i.e. denileukin diftitox (Ontak®) or agalsidase beta (Fabrazyme®). The second is the opportunity to use protein toxin architecture to reach targets that are not normally accessible. This may be achieved by grafting regulatory domains from multiple species to form synthetic proteins, engineered to do multiple jobs. Examples include access to the nucleocytosolic compartment. Herein the use of synthetic proteins for drug delivery has been reviewed

Measurement of the splashback feature around SZ-selected Galaxy clusters with DES, SPT, and ACT

We present a detection of the splashback feature around galaxy clusters selected using the Sunyaev–Zel’dovich (SZ) signal. Recent measurements of the splashback feature around optically selected galaxy clusters have found that the splashback radius, rsp, is smaller than predicted by N-body simulations. A possible explanation for this discrepancy is that rsp inferred from the observed radial distribution of galaxies is affected by selection effects related to the optical cluster-finding algorithms. We test this possibility by measuring the splashback feature in clusters selected via the SZ effect in data from the South Pole Telescope SZ survey and the Atacama Cosmology Telescope Polarimeter survey. The measurement is accomplished by correlating these cluster samples with galaxies detected in the Dark Energy Survey Year 3 data. The SZ observable used to select clusters in this analysis is expected to have a tighter correlation with halo mass and to be more immune to projection effects and aperture-induced biases, potentially ameliorating causes of systematic error for optically selected clusters. We find that the measured rsp for SZ-selected clusters is consistent with the expectations from simulations, although the small number of SZ-selected clusters makes a precise comparison difficult. In agreement with previous work, when using optically selected redMaPPer clusters with similar mass and redshift distributions, rsp is ∼2σ smaller than in the simulations. These results motivate detailed investigations of selection biases in optically selected cluster catalogues and exploration of the splashback feature around larger samples of SZ-selected clusters. Additionally, we investigate trends in the galaxy profile and splashback feature as a function of galaxy colour, finding that blue galaxies have profiles close to a power law with no discernible splashback feature, which is consistent with them being on their first infall into the cluster

The SPTPoL extended cluster survey

We describe the observations and resultant galaxy cluster catalog from the 2770 deg2 SPTpol Extended Cluster Survey (SPT-ECS). Clusters are identified via the Sunyaev-Zel'dovich (SZ) effect and confirmed with a combination of archival and targeted follow-up data, making particular use of data from the Dark Energy Survey (DES). With incomplete follow-up we have confirmed as clusters 244 of 266 candidates at a detection significance ξ ≥ 5 and an additional 204 systems at 4 4 threshold, and 10% of their measured SZ flux. We associate SZ-selected clusters, from both SPT-ECS and the SPT-SZ survey, with clusters from the DES redMaPPer sample, and we find an offset distribution between the SZ center and central galaxy in general agreement with previous work, though with a larger fraction of clusters with significant offsets. Adopting a fixed Planck-like cosmology, we measure the optical richness-SZ mass (l - M) relation and find it to be 28% shallower than that from a weak-lensing analysis of the DES data-a difference significant at the 4σ level-with the relations intersecting at λ = 60. The SPT-ECS cluster sample will be particularly useful for studying the evolution of massive clusters and, in combination with DES lensing observations and the SPT-SZ cluster sample, will be an important component of future cosmological analyses

Remediation of fluency: Word specific or generalised training effects?

The present study examines whether reading fluency benefits more from repeated reading of a limited set of words or from practicing reading with many different words. A group of 37 reading delayed Dutch children repeatedly read the same 20 words with limited exposure duration, whereas another group of 37 poor readers received the same reading exercises with 400 different words. Results demonstrated that improvements in accuracy and speed of trained words were larger for the repeated reading group than for the children who had only practiced with these words once. No difference in generalisation of effects to untrained neighbour and control words was found between the two conditions. Furthermore, rapid naming skill was unrelated to improvements in reading fluency and transfer effects in both training conditions. Results demonstrate that the practical value of repeated reading lies in its word specific training effects. © Springer 2006