The induction of natural competence adapts staphylococcal metabolism to infection

A central question concerning natural competence is why orthologs of competence genes are conserved in non-competent bacterial species, suggesting they have a role other than in transformation. Here we show that competence induction in the human pathogen Staphylococcus aureus occurs in response to ROS and host defenses that compromise bacterial respiration during infection. Bacteria cope with reduced respiration by obtaining energy through fermentation instead. Since fermentation is energetically less efficient than respiration, the energy supply must be assured by increasing the glycolytic flux. The induction of natural competence increases the rate of glycolysis in bacteria that are unable to respire via upregulation of DNA- and glucose-uptake systems. A competent-defective mutant showed no such increase in glycolysis, which negatively affects its survival in both mouse and Galleria infection models. Natural competence foster genetic variability and provides S. aureus with additional nutritional and metabolic possibilities, allowing it to proliferate during infection

Search for muon neutrinos from gamma-ray bursts with the ANTARES neutrino telescope using 2008 to 2011 data

9 pages, 8 figures; added Fig. 1 with effective area, updated Fig. 8 (b) according to arXiv:1204.4219 ; Références publication Astron Astrophys 559 (2013) A9International audienceAims. We search for muon neutrinos in coincidence with GRBs with the ANTARES neutrino detector using data from the end of 2007 to 2011. Methods. Expected neutrino fluxes were calculated for each burst individually. The most recent numerical calculations of the spectra using the NeuCosmA code were employed, which include Monte Carlo simulations of the full underlying photohadronic interaction processes. The discovery probability for a selection of 296 GRBs in the given period was optimised using an extended maximum-likelihood strategy. Results. No significant excess over background is found in the data, and 90% confidence level upper limits are placed on the total expected flux according to the model

Exploring Attitudes Toward “Sugar Relationships” Across 87 Countries: A Global Perspective on Exchanges of Resources for Sex and Companionship

The current study investigates attitudes toward one form of sex for resources: the so-called sugar relationships, which often involve exchanges of resources for sex and/or companionship. The present study examined associations among attitudes toward sugar relationships and relevant variables (e.g., sex, sociosexuality, gender inequality, parasitic exposure) in 69,924 participants across 87 countries. Two self-report measures of Acceptance of Sugar Relationships (ASR) developed for younger companion providers (ASR-YWMS) and older resource providers (ASR-OMWS) were translated into 37 languages. We tested cross-sex and cross-linguistic construct equivalence, cross-cultural invariance in sex differences, and the importance of the hypothetical predictors of ASR. Both measures showed adequate psychometric properties in all languages (except the Persian version of ASR-YWMS). Results partially supported our hypotheses and were consistent with previous theoretical considerations and empirical evidence on human mating. For example, at the individual level, sociosexual orientation, traditional gender roles, and pathogen prevalence were significant predictors of both ASR-YWMS and ASR-OMWS. At the country level, gender inequality and parasite stress positively predicted the ASR-YWMS. However, being a woman negatively predicted the ASR-OMWS, but positively predicted the ASR-YWMS. At country-level, ingroup favoritism and parasite stress positively predicted the ASR-OMWS. Furthermore, significant cross-subregional differences were found in the openness to sugar relationships (both ASR-YWMS and ASR-OMWS scores) across subregions. Finally, significant differences were found between ASR-YWMS and ASR-OMWS when compared in each subregion. The ASR-YWMS was significantly higher than the ASR-OMWS in all subregions, except for Northern Africa and Western Asia

Predictors of Enhancing Human Physical Attractiveness: Data from 93 Countries

People across the world and throughout history have gone to great lengths to enhance their physical appearance. Evolutionary psychologists and ethologists have largely attempted to explain this phenomenon via mating preferences and strategies. Here, we test one of the most popular evolutionary hypotheses for beauty-enhancing behaviors, drawn from mating market and parasite stress perspectives, in a large cross-cultural sample. We also test hypotheses drawn from other influential and non-mutually exclusive theoretical frameworks, from biosocial role theory to a cultural media perspective. Survey data from 93,158 human participants across 93 countries provide evidence that behaviors such as applying makeup or using other cosmetics, hair grooming, clothing style, caring for body hygiene, and exercising or following a specific diet for the specific purpose of improving ones physical attractiveness, are universal. Indeed, 99% of participants reported spending \u3e10 min a day performing beauty-enhancing behaviors. The results largely support evolutionary hypotheses: more time was spent enhancing beauty by women (almost 4 h a day, on average) than by men (3.6 h a day), by the youngest participants (and contrary to predictions, also the oldest), by those with a relatively more severe history of infectious diseases, and by participants currently dating compared to those in established relationships. The strongest predictor of attractiveness-enhancing behaviors was social media usage. Other predictors, in order of effect size, included adhering to traditional gender roles, residing in countries with less gender equality, considering oneself as highly attractive or, conversely, highly unattractive, TV watching time, higher socioeconomic status, right-wing political beliefs, a lower level of education, and personal individualistic attitudes. This study provides novel insight into universal beauty-enhancing behaviors by unifying evolutionary theory with several other complementary perspectives

3D Elements for Phased-Array Systems: Analysis and Design

In recent years, radar systems and satellite communications require phased array antennas that are capable of incorporating frequency and angular selectivity while maintaining a low profile. Active phased array antennas must comply with stringent requirements in terms of sensitivity to interference caused by other nearby radiating systems, especially in complex platforms, where a multitude of sensors and radiating systems need to co-exist. In such environments, antennas working at different frequencies can interfere with each other and the implementation of frequency filtering functions with a good out-of-band rejection are needed. Moreover, the interference between different systems can be mitigated by reducing the radiation in the direct path between them. For this purpose, angular filtering functions for pattern shaping can be beneficial. However, standard planar printed circuit board technology puts constraints on the possible antenna elements that can be realized to achieve frequency and angular selectivity. Thus, using new methods such as additive manufacturing technology and 3D printing can provide more degrees of freedom to fabricate complex geometries with a desired operation. For these reasons, this work focuses on studying new solutions for frequency selectivity with rejection of higher order harmonics, developing a spectral method of moment to study antennas to achieve angular shaping and finding the guidelines needed to design such antennas, and testing additive manufacturing technology to find its suitability at high frequencies for phased array antennas. A bandpass miniaturize-element frequency selective surface with harmonic rejection properties has been designed and manufactured. The design is based on an equivalent circuit model, taking a 3-pole Chebyshev bandpass filter as a starting point, where the inter-layer interaction is only described with a single transmission line representing the fundamental Floquet wave. The prototype consists of five metallic layers, interdigitated patches and grids, separated by dielectric slabs and exhibiting good stability over a wide conical incidence range. A practical case to estimate the effects of placing the FSS in the proximity of a wide-scanning wideband connected array of dipoles has been performed. The performance of the array combined with the FSS has been experimentally characterized, defining the optimal distance between FSS and array to avoid the propagation of surface waves between both structures, showing a good response within the FSS bandwidth and a good frequency rejection outside of this bandwidth. A spectral method of moments for tilted elements in free space and in the presence of a backing reflector for infinite and finite arrays has been derived. Such method allows to study dipole and stacked dipole elements and find the guidelines needed to design, in a future, a phased array antenna with an undesired angular range where suppression of gain is intended. The parametric study concluded that the main parameters that shapes the pattern are the inter-element distance between elements and the tilt angle of the elements. The requirements to achieve an asymmetric radiation pattern are a directive element and an inter-elements distance higher than half wavelength, while the tilt of the elements allows to shape the gain levels in the suppressed angular region. To validate this study a linear arrays consisting of tilted dipoles loaded with artificial dielectric layers has been fabricated. The prototype shows a good comparison with simulations and measurements. A simple design of a dipole antenna has been derived and fabricated using Stereolithography process as an additive manufacturing method. The polymer and metal paste used in the process have been characterized and results have been discussed. A good agreement between simulations and measurements has been achieved after including the geometric deviations found in the fabricated antenna. The fabrication process for high frequencies appears to be prone to systematic errors and the challenges related to the use of additive manufacturing technology for high frequency RF antennas and components has been discussed.Tera-Hertz Sensin

3D Array Element Design for Pattern Shaping

In this work, antenna arrays with tilted dipoles are investigated in terms of radiation and impedance properties. A spectral method of moments (MoM) was developed for the analysis of doubly-periodic arrays (i.e. periodic in both x and ydirections)with arbitrarily tilted dipole elements, in free space or in the presence of a backing reflector. By the aid of this analysis method, the radiation characteristics of arrays of stacked dipoles over a ground plane are studied, highlighting the variation of thepatterns as a function of the inter-element distance and the angle of inclination of the elements

Theory and design of an array of skewed stacked dipoles

We propose a systematic approach to describe planar slot antennas, embedded in generic stratified media. An equivalent transmission line model for the slot is proposed, based on a spectral domain analysis. First, we introduce a method of moments solution to model semi-infinite slots, fed by a deltagap excitation. The solution entails only two basis functions, one located at the feed and the other at the termination. The latter basis function is chosen to properly account for the field diffractive behavior at the antenna end point. An approximate circuit model is then introduced, which describes the main mode propagating along the slot as an equivalent transmission line. Lumped impedances are extracted to accurately describe the source and the end point. This procedure can be used to derive the input impedance of planar antennas with arbitrary length in generic layered media or the interaction between multiple feeds within the same slot

On the radiation properties of array of skewed stacked dipoles

Antenna arrays located on airplanes or other mobile platforms for satellite communication applications are typically required to support very large scan angles (close to end-_re). How- ever, planar antenna arrays are typically characterized by scan loss. To increase the scan range conformal arrays and multi-panel configuration can be found in literature, but the height of the structures is still too large to be installed on airplanes without significant impact on the aircraft drag. To obtain wide-scan capability while still maintaining a low antenna profile, hybrid scanning mechanism are currently implemented (F. Tiezzi et al., Eu- CAP, 2010). The idea is to scan the beam electronically from broadside to a positive, as high as possible, angle and then to achieve the full coverage by mechanical rotation of the array along the azimuth. In this work we present a study to determine the parameters affecting the power radiated in specific directions by antenna arrays with tilted elements. We developed an efficient Method of Moments (MoM) for the analysis of linear arrays with arbitrarily tilted dipole elements, in free space or in the presence of a backing reflector. By using this analysis method, we study the radiation characteristics of arrays of stacked dipoles over a ground plane, highlighting the variation of the patterns as a function of the inter-element distance and the angle of inclination of the element. For half wavelength inter-element distance the array pattern is rather symmetric even for tilted elements, as expected from the Floquet theory (A.K. Bhattacharyya et al., IEEE TAP, 51, 1572-1581, 2003). However, when the elements are tilted by positive angles and for inter-element distance larger than half wavelength, a null and a reduction in directivity in the radiation pattern is achieved for negative scanning angles. Grating lobes in the visible region are weighted by element pattern. The minimum of the radiation pattern is not necessarily aligned with the dipole axis but, due to mutual coupling, it can move to different angles depending on the combination of inclination angle and distance. The array directivity is almost at for positive angles up to very large scanning directions, and decreases rapidly at specific negative angles that change with the inter-element distance. Moreover, it is shown that, for large arrays (i.e. with more than 10 elements), the shape of the active element pattern does not change significantly as a function of the number of elements. At the conference considerations concerning the effects on the active element pattern of mutual coupling and of the onset of grating lobes for a given grid size/tilt angle will be presented. Moreover, a linear array design with selective pattern characteristics will be presented

Financial Impact of COVID-19 on Dental Care for Pediatric Patients: a Dental Claims Review

Purpose: The purpose of this study was to quantify the impact of the COVID-19 pandemic on private dental insurance claims for pediatric dental care. Methods: Commercial dental insurance claims for patients in the United States ages 18 and younger were obtained and analyzed. The claims dates ranged from January 1, 2019, to August 31, 2020. Total claims paid, average paid amount per visit, and the number of visits were compared between provider specialties and patient age groups from 2019 to 2020. Results: Total paid claims and total number of visits per week were significantly lower in 2020 compared to 2019 from mid-March to mid-May (P0.15), except for significantly lower total paid claims and visits per week for "other" specialists in 2020 (P<0.005). The average paid amount per visit was significantly higher during the COVID shutdown period for 0-5 year-olds (P<0.001) but significantly lower for all other ages. Conclusions: Dental care was greatly reduced during the COVID shutdown period and was slower to recover for "other" specialties. Younger patients ages zero to five years had more expensive dental visits during the shutdown period

Theory and design of an array of skewed stacked dipoles

We propose a systematic approach to describe planar slot antennas, embedded in generic stratified media. An equivalent transmission line model for the slot is proposed, based on a spectral domain analysis. First, we introduce a method of moments solution to model semi-infinite slots, fed by a deltagap excitation. The solution entails only two basis functions, one located at the feed and the other at the termination. The latter basis function is chosen to properly account for the field diffractive behavior at the antenna end point. An approximate circuit model is then introduced, which describes the main mode propagating along the slot as an equivalent transmission line. Lumped impedances are extracted to accurately describe the source and the end point. This procedure can be used to derive the input impedance of planar antennas with arbitrary length in generic layered media or the interaction between multiple feeds within the same slot.Tera-Hertz Sensin