Absorption in quantum electrodynamics cavities in terms of a quantum jump operator

We describe the absorption by the walls of a quantum electrodynamics cavity as a process during which the elementary excitations (photons) of an internal mode of the cavity exit by tunneling through the cavity walls. We estimate by classical methods the survival time of a photon inside the cavity and the quality factor of its mirrors

Weakly convex sets and modulus of nonconvexity

We consider a definition of a weakly convex set which is a generalization of the notion of a weakly convex set in the sense of Vial and a proximally smooth set in the sense of Clarke, from the case of the Hilbert space to a class of Banach spaces with the modulus of convexity of the second order. Using the new definition of the weakly convex set with the given modulus of nonconvexity we prove a new retraction theorem and we obtain new results about continuity of the intersection of two continuous set-valued mappings (one of which has nonconvex images) and new affirmative solutions of the splitting problem for selections. We also investigate relationship between the new definition and the definition of a proximally smooth set and a smooth set

Ancestral genome estimation reveals the history of ecological diversification in Agrobacterium

Horizontal gene transfer (HGT) is considered as a major source of innovation in bacteria, and as such is expected to drive adaptation to new ecological niches. However, among the many genes acquired through HGT along the diversification history of genomes, only a fraction may have actively contributed to sustained ecological adaptation. We used a phylogenetic approach accounting for the transfer of genes (or groups of genes) to estimate the history of genomes in Agrobacterium biovar 1, a diverse group of soil and plant-dwelling bacterial species. We identified clade-specific blocks of cotransferred genes encoding coherent biochemical pathways that may have contributed to the evolutionary success of key Agrobacterium clades. This pattern of gene coevolution rejects a neutral model of transfer, in which neighboring genes would be transferred independently of their function and rather suggests purifying selection on collectively coded acquired pathways. The acquisition of these synapomorphic blocks of cofunctioning genes probably drove the ecological diversification of Agrobacterium and defined features of ancestral ecological niches, which consistently hint at a strong selective role of host plant rhizospheres

First high-resolution look at the quiet Sun with ALMA at 3 mm

We present an overview of high resolution quiet Sun observations, from disk center to the limb, obtained with the Atacama Large mm and sub-mm Array (ALMA) at 3 mm. Seven quiet Sun regions were observed with resolution of up to 2.5" by 4.5". We produced both average and snapshot images by self-calibrating the ALMA visibilities and combining the interferometric images with full disk solar images. The images show well the chromospheric network, which, based on the unique segregation method we used, is brighter than the average over the fields of view of the observed regions by $\sim 305$ K while the intranetwork is less bright by $\sim 280$ K, with a slight decrease of the network/intranetwork contrast toward the limb. At 3 mm the network is very similar to the 1600 \AA\ images, with somewhat larger size. We detected for the first time spicular structures, rising up to 15" above the limb with a width down to the image resolution and brightness temperature of $\sim$ 1800 K above the local background. No trace of spicules, either in emission or absorption, was found on the disk. Our results highlight ALMA's potential for the study of the quiet chromosphere.Comment: Astronomy and Astrophysics (Letters), in pres

Using SIMCTS framework to model determinants of customer satisfaction: a case in an ISP

In this paper we describe a call center simulation case study that uses real data obtained from an Internet Service Provider (ISP). The case study is conducted using SIMCTS (Simulation Modelling and Analysis of Customer Satisfaction Patterns for Telecommunication Service Providers) framework [25]. The applicability of this framework to model ISP business scenario is discussed in detail. The simulation case study reveal that the dimensions of service quality have huge impact on customer satisfaction and also provide valuable insight in to gap analysis of customer perception and expectation. Various key satisfaction variables in relation to call center are modelled using SIMAN simulation language and ARENA simulation software. The simulation case study investigates service quality dimension, technical (or) functional service quality and their role in evaluation of overall satisfaction judgment. The simulation model collects transient performance measures which can be used to make competitive marketing decisions

Comparison of pelvic floor dysfunction 6 years after uncomplicated vaginal versus elective cesarean deliveries: a cross-sectional study.

Clinicians and patients have traditionally believed that elective cesarean section may protect against certain previously ineluctable consequences of labor, including a plethora of urinary, anorectal and sexual dysfunctions. We aimed to evaluate fecal, urinary and sexual symptoms 6 years postpartum, comparing uncomplicated vaginal delivery and elective cesarean delivery, and to assess their impact on quality of life. We conducted a cross-sectional study to compare perineal functional symptomatology between women having singleton elective cesarean deliveries (eCS) and singleton uncomplicated vaginal deliveries (uVD). Women who delivered 6 years before this study were chosen randomly from our hospital database. This database includes demographic, labor, and delivery information, as well as data regarding maternal and neonatal outcomes, all of which is collected at the time of delivery by the obstetrician. Four validated self-administrated questionnaires were sent by post to the participants: the short forms of the Urogenital Distress Inventory, Incontinence Impact Questionnaire, Wexner fecal incontinence scale, and Female Sexual Function Index. Current socio-demographic details, physical characteristics, obstetrical history and mode of delivery at subsequent births were also registered using a self-reported questionnaire. A total of 309 women with uVD and 208 with eCS returned postal questionnaires. The response rate was 49%. Socio-demographic characteristics and fecal incontinence were similar between groups. After eCS, women reported significantly less urgency urinary incontinence (adjusted Relative Risk 0.55; 95% confidence interval 0.34-0.88) and stress incontinence (adjusted Relative Risk 0.53; 95% confidence interval 0.35-0.80) than after uVD. No difference in total Incontinence Impact Questionnaire score was found between both modes of delivery. Lower abdominal or genital pain (adjusted Relative Risk 1.58; 95% confidence interval 1.01-2.49) and pain related to sexual activity (adjusted Relative Risk 2.50; 95% confidence interval 1.19-5.26) were significantly more frequent after eCS than uVD. Six years postpartum, uVD is associated with urinary incontinence, while eCS is associated with sexual and urination pain

Microscale Structures on the Quiet Sun and Coronal Heating

We present some results concerning transient brightenings on the quiet Sun, based on data from the Extreme-Ultraviolet Imaging Telescope on board the Solar and Heliospheric Observatory. Histograms of intensity are found to be well fitted by χ2 distributions for small values of the intensity, while at high intensities power-law distributions are always observed. Also, the emission presents the same statistical properties when the resolution is downgraded by local averaging; i.e., it appears to be self-similar down to the resolution scale of the instruments. These properties are characteristic of the emission from a forced turbulent system whose dissipation scale is much smaller than the pixel dimension. On the basis of the data presented as well as other published results and our present theoretical understanding of MHD turbulence, we discuss the realism of the nanoflare scenario of coronal heating

Measuring latency distribution of transcallosal fibers using transcranial magnetic stimulation

Background: Neuroimaging technology is being developed to enable non-invasive mapping of the latency distribution of cortical projection pathways in white matter, and correlative clinical neurophysiological techniques would be valuable for mutual verification. Interhemispheric interaction through the corpus callosum can be measured with interhemispheric facilitation and inhibition using transcranial magnetic stimulation. Objective: To develop a method for determining the latency distribution of the transcallosal fibers with transcranial magnetic stimulation. Methods: We measured the precise time courses of interhemispheric facilitation and inhibition with a conditioning-test paired-pulse magnetic stimulation paradigm. The conditioning stimulus was applied to the right primary motor cortex and the test stimulus was applied to the left primary motor cortex. The interstimulus interval was set at 0.1 ms resolution. The proportions of transcallosal fibers with different conduction velocities were calculated by measuring the changes in magnitudes of interhemispheric facilitation and inhibition with interstimulus interval. Results: Both interhemispheric facilitation and inhibition increased with increment in interstimulus interval. The magnitude of interhemispheric facilitation was correlated with that of interhemispheric inhibition. The latency distribution of transcallosal fibers measured with interhemispheric facilitation was also correlated with that measured with interhemispheric inhibition. Conclusions: The data can be interpreted as latency distribution of transcallosal fibers. Interhemispheric interaction measured with transcranial magnetic stimulation is a promising technique to determine the latency distribution of the transcallosal fibers. Similar techniques could be developed for other cortical pathways