Search

Aim In Japan, the criteria of the latent and active phases of the first stage of labor have not been decided. The Japan Society of Obstetrics and Gynecology (JSOG) Perinatal Committee conducted a study to construct a spontaneous labor curve in order to determine the point of onset of the active phase. Methods The participants were women who had spontaneous deliveries at four health facilities in Japan between September 1, 2011, and September 31, 2019. Spontaneous delivery was defined as the spontaneous onset of labor at term (37 weeks, 0 days to 41 weeks, 6 days) with vaginal delivery of a mature fetus in a cephalic position without uterotonic agents or epidural analgesia. The time points for each "cm" of dilation were collected starting from the time of full dilation retrogradely. The relationship between time since labor onset and cervical dilation was expressed as a curve using a smoothing B-spline. Results A total of 4215 primiparous and 5266 multiparous women were included in this study. The spontaneous labor curve showed that in both primiparous and multiparous women, labor progress was slow until 5 cm cervical dilation, accelerating between 5 and 6 cm dilation, and steadily progressed after 6 cm dilation. Conclusion We propose that the active phase of the first stage of labor be defined as starting at 5 cm dilation of the cervix, and that it be divided into an acceleration phase (5-6 cm dilation) and a maximal phase (>6 cm dilation).

OBJECTIVE To compare, in terms of anatomical, functional, and sexual aspects, two types of treatment for women with vaginal agenesis: progressive dilation or surgical neovaginoplasty. METHODS Women with vaginal agenesis underwent either dilation treatment using the Frank method or surgical treatment using the modified Abbe-McIndoe technique with oxidized cellulose. Patients were evaluated 3-6 months after treatment for a follow-up including medical history, physical examination, general satisfaction, clinical aspect of the vagina, Female Sexual Function Index, and three-dimensional pelvic floor ultrasound. RESULTS In total, 20 women with vaginal agenesis were included in the present study; nine in the dilation group and 11 in the surgical group. A comparison between the groups (vaginal dilation and surgical neovaginoplasty) showed efficacy in neovagina formation after both treatments, with a statistically significant difference between the pre- and post-treatment periods (P value pre- × post-dilation group

Objectives The primary goal of this study was to examine how well findings of cervical esophageal stenosis on modified barium swallow (MBS) and esophagram correlate with clinical improvement following dilation in patients with a history of head and neck (H&N) cancer. Methods A retrospective review was performed at an academic hospital. The study population included H&N cancer patients with a history of neck dissection surgery who underwent esophageal dilation from 2010 to2018. Pre and postdilation swallowing function was assessed. The Functional Outcomes Swallowing Scale (FOSS) and Functional Oral Intake Scale (FOIS) were used as outcome measures. Results The 95 patients were included. All patients had imaging prior to dilation. Post‐dilation FOSS and FOIS scores were significantly improved (P, The aim of this study was to determine the ability of the modified barium swallow (MBS) and esophagram to accurately predict cervical esophageal stenosis in patients with history of head and neck cancer that would benefit from esophageal dilation. A retrospective review was performed at an academic hospital of patients who had previous neck dissection surgery for cancer and underwent esophageal dilation from 2010‐2018. These imaging studies appear to have mixed reliability as predictors of response to esophageal dilation in this population that is high risk for cervical esophageal stenosis.

We study the space of all $d$-tuples of unitaries $u=(u_1,\ldots, u_d)$ using dilation theory and matrix ranges. Given two $d$-tuples $u$ and $v$ generating C*-algebras $\mathcal A$ and $\mathcal B$, we seek the minimal dilation constant $c=c(u,v)$ such that $u\prec cv$, by which we mean that $u$ is a compression of some $*$-isomorphic copy of $cv$. This gives rise to a metric \[ d_D(u,v)=\log\max\{c(u,v),c(v,u)\} \] on the set of equivalence classes of $*$-isomorphic tuples of unitaries. We also consider the metric \[ d_{HR}(u,v)=\inf\left\{\|u'-v'\|:u',v'\in B(H)^d, u'\sim u\textrm{ and } v'\sim v\right\}, \] and we show the inequality \[ d_{HR}(u,v)\leq K d_D(u,v)^{1/2}. \] Let $u_\Theta$ be the universal unitary tuple $(u_1,\ldots,u_d)$ satisfying $u_\ell u_k=e^{i\theta_{k,\ell}} u_k u_\ell$, where $\Theta=(\theta_{k,\ell})$ is a real antisymmetric matrix. We find that $c(u_\Theta, u_{\Theta'})\leq e^{\frac{1}{4}\|\Theta-\Theta'\|}$. From this we recover the result of Haagerup-Rordam and Gao that there exists a map $\Theta\mapsto U(\Theta)\in B(H)^d$ such that $U(\Theta)\sim u_\Theta$ and \[ \|U(\Theta)-U({\Theta'})\|\leq K\|\Theta-\Theta'\|^{1/2}. \] Of special interest are: the universal $d$-tuple of noncommuting unitaries ${\mathrm u}$, the $d$-tuple of free Haar unitaries $u_f$, and the universal $d$-tuple of commuting unitaries $u_0$. We obtain the bounds \[ 2\sqrt{1-\frac{1}{d}}\leq c(u_f,u_0)\leq 2\sqrt{1-\frac{1}{2d}}. \] From this, we recover Passer's upper bound for the universal unitaries $c({\mathrm u},u_0)\leq\sqrt{2d}$. In the case $d=3$ we obtain the new lower bound $c({\mathrm u},u_0)\geq 1.858$ improving on the previously known lower bound $c({\mathrm u},u_0)\geq\sqrt{3}$., Comment: 31 pages. A few minor corrections have been made and a new appendix (Appendix B) has been added. To appear in Journal of the London Mathematical Society

It is necessary to hold the scope in the optimum position when performing endoscopy, especially when performing treatments such as interventional endoscopy. During interventional endoscopic ultrasound (EUS) such as EUS-guided biliary drainage, it is important to keep the scope position from the time of puncture so as to maintain a good position where the force is most easily transmitted to the devices during puncture route dilation or stent insertion.

The vascular endothelium plays a crucial role to regulate vascular tone. Severe acute respiratory syndrome coronavirus‐2 (SARS‐CoV‐2) infection is known to cause vascular endothelial dysfunction. However, the long‐term effects of SARS‐CoV‐2 in resistance vessels remains unknown. This study is designed to test whether endothelium‐dependent vasodilation in human arterioles remains impaired after clearance of SARS‐CoV‐2 virus. Fresh human adipose tissues were obtained as discarded surgical specimens from control subjects (n=15, no SARS‐CoV‐2 exposure, 46.7±4 years) and previously SARS‐CoV‐2 positive subjects (PSPSs: n=8, 35.8±3.8 years). Among PSPSs, the time between positive and negative SARS‐CoV‐2 test results was ≤3 months (n=6) or 8 months (n=2). Isolated arterioles (100‐200 µm) were cannulated under 60 mmHg and examined for diameter changes to acetylcholine (ACh; 10−9 to 10−5 M) and sodium nitroprusside (SNP: 10−9 to 10−4 M) using videomicroscopy. Flow‐mediated dilation (FMD) was recorded at steady‐state during graded increases in intraluminal pressure gradients (5‐100 cm H2O). Dilation to ACh and FMD in arterioles from PSPSs was significantly reduced (ACh max. dilation at 10−5 M: 60±6% vs. 92.8±3.9% in control, n=7‐8, P

We present a completely new structure theoretic approach to the dilation theory of linear operators. Our main result is the following theorem: if $X$ is a super-reflexive Banach space and $T$ is contained in the weakly closed convex hull of all invertible isometries on $X$, then $T$ admits a dilation to an invertible isometry on a Banach space $Y$ with the same regularity as $X$. The classical dilation theorems of Sz.-Nagy and Akcoglu-Sucheston are easy consequences of our general theory.

We consider the stochastic, single-machine earliness/tardiness problem (SET), with the sequence of processing of the jobs and their due-dates as decisions and the objective of minimizing the sum of the expected earliness and tardiness costs over all the jobs. In a recent paper, Baker (2014) shows the optimality of the Shortest-Variance-First (SVF) rule under the following two assumptions: (a) The processing duration of each job follows a normal distribution. (b) The earliness and tardiness cost parameters are the same for all the jobs. In this study, we consider problem SET under assumption (b). We generalize Baker's result by establishing the optimality of the SVF rule for more general distributions of the processing durations and a more general objective function. Specifically, we show that the SVF rule is optimal under the assumption of dilation ordering of the processing durations. Since convex ordering implies dilation ordering (under finite means), the SVF sequence is also optimal under convex ordering of the processing durations. We also study the effect of variability of the processing durations of the jobs on the optimal cost. An application of problem SET in surgical scheduling is discussed.

Summary Hyper-star graph HS(2n,n) was introduced to be a competitive model to both hypercubes and star graphs. In this paper, we study its properties by (1) giving a closed form solution to the surface area of HS(2n,n), (2) discussing its Hamiltonicity by establishing an isomorphism between the graph and the well-known middle levels problem, and (3) showing that full binary trees can be embedded into HS(2n,n) with dilation 1. We also develop a single-port optimal neighbourhood broadcasting algorithm for HS(2n,n). Copyright © 2015 John Wiley & Sons, Ltd.

In some longitudinal studies the initiation time of the process is not clearly defined, yet it is important to make inference or do predictions about the longitudinal process. The application of interest in this article is to provide a framework for modeling individualized labor curves (longitudinal cervical dilation measurements) where the start of labor is not clearly defined. This is a well-known problem in obstetrics where the benchmark reference time is often chosen as the end of the process (individuals are fully dilated at 10 cm) and time is run backwards. This approach results in valid and efficient inference unless subjects are censored before the end of the process, or if we are focused on prediction. Providing dynamic individualized predictions of the longitudinal labor curve prospectively (where backwards time is unknown) is of interest to aid obstetricians to determine if a labor is on a suitable trajectory. We propose a model for longitudinal labor dilation that uses a random-effects model with unknown time-zero and a random change point. We present a maximum likelihood approach for parameter estimation that uses adaptive Gaussian quadrature for the numerical integration. Further, we propose a Monte Carlo approach for dynamic prediction of the future longitudinal dilation trajectory from past dilation measurements. The methodology is illustrated with longitudinal cervical dilation data from the Consortium of Safe Labor Study.

In this paper, the irreducible p, q-representations of the Lie algebras and are discussed. We prove two theorems that classify certain irreducible p, q-representations of these Lie algebras and construct their one variable models in terms of p, q-derivative and dilation operators. As an application, we derive a p, q-special function identity based on one such model.

Ensemble forecasts of (u,v)-wind are of crucial importance for a number of decision-making problems related to e.g. air traffic control, ship routeing and energy management. The skill of these ensemble forecasts as generated by NWP-based models can be maximised by correcting for their lack of sufficient reliability. The original framework introduced here allows for an adaptive bivariate calibration of these ensemble forecasts. The originality of this methodology lies in the fact that calibrated ensembles still consist of a set of (space–time) trajectories, after translation and dilation. In parallel, the parameters of the models employed for improving the stochastic properties of the generating processes involved are adaptively and recursively estimated to accommodate smooth changes in the process characteristics and to lower computational costs. The approach is applied and evaluated based on the adaptive calibration of ECMWF ensemble forecasts of (u,v)-wind at 10 m above ground level over Europe over a three-year period between December 2006 and December 2009. Substantial improvements in (bivariate) reliability and in various deterministic/probabilistic scores are observed. Finally, the maps of translation and dilation factors are discussed. Copyright © 2012 Royal Meteorological Society

Fractal geometry can be used for determining the morphological boundaries of metropolitan areas. A two-step method is proposed here: (1) Minkowski's dilation is applied to detect any multiscale spatial discontinuity and (2) a distance threshold is located on the dilation curve corresponding to a major change in its behavior. We therefore measure the maximum curvature of the dilation curve. The method is tested on theoretical urban patterns and on several European cities to identify their morphological boundaries and to track boundary changes over space and time. Results obtained show that cities characterized by comparable global densities may exhibit different distance thresholds. The less the distance separating buildings differ between an urban agglomeration and its surrounding built landscape, the greater the distance threshold. The few the buildings that are connected across scales, the greater the distance threshold.

Some Bayesians have suggested that beliefs based on ambiguous or incomplete evidence are best represented by families of probability functions. I spend the first half of this essay outlining one version of this imprecise model of belief, and spend the second half defending the model against recent objections, raised by Roger White and others, which concern the phenomenon of probabilistic dilation. Dilation occurs when learning some definite fact forces a person‟s beliefs about an event to shift from a sharp, point-valued subjective probability to an imprecise spread of probabilities. Some commentators find dilation disturbing, both from an epistemic and a decision-theoretic perspective, and place the blame on the use of sets of probabilities to model opinion. These reactions are based on an overly narrow conception of imprecise belief states, which assumes that we know everything there is to know about a person‟s doxastic attitudes once we have identified the spreads of values for her imprecise credences. Once we recognize that the imprecise model has the resources to characterize a much richer family of doxastic attitudes than this, we will see that White‟s charges of epistemological and decision theoretic incoherence are unfounded.

Color-space metrics are considered and three main aspects are analyzed: (1) the distinction between small and large color differences; (2) the relation between space metrics and color-difference formulae; (3) the color-scale comparison between CIE 1931 and CIE 1964 observers.The analysis, based on daylight adaptation, is made for the 2° visual field on a chromaticity diagram with uniform scales according with the MacAdam ellipses1 and, for the 10° visual field, on the OSA-UCS.2,3 The conclusions are: (i) the main difference between 2° and 10° observers is a proper dilation of the chromaticity scales; (ii) the chroma scale of the Munsell system is uniform for the 10° visual field; (iii) the scales of the Munsell system are in good agreement with those of OSA-UCS; (iv) the usual color-difference formulae (CMC, CIE94) represented on the OSA-UCS space show a distortion that seems due to their definition in the CIELAB space; the BFD formula shows a lower distortion. © 2001 John Wiley & Sons, Inc. Col Res Appl, 26, 351–361, 2001

The uniqueness up to translation of the characterization of random compact sets in Euclidean space by their dilation volumes is shown. The unique correspondence is shown to be a homeomorphism with respect to suitable topologies. If set differences of volume zero are neglected, dilations by three-point sets are sufficient to determine a non-random compact set and the correspondence is again a homeomorphism with respect to vague topologies.