One, two, or three stars? An investigation of an unusual eclipsing binary candidate undergoing dramatic period changes

We report our investigation of 1SWASP J234401.81-212229.1, a variable with a 18 461.6 s period. After identification in a 2011 search of the SuperWASP archive for main-sequence eclipsing binary candidates near the distribution's short-period limit of ~0.20 d, it was measured to be undergoing rapid period decrease in our earlier work, though later observations supported a cyclic variation in period length. Spectroscopic data obtained in 2012 with the Southern African Large Telescope did not, however, support the interpretation of the object as a normal eclipsing binary. Here, we consider three possible explanations consistent with the data: a single-star oblique rotator model in which variability results from stable cool spots on opposite magnetic poles; a two-star model in which the secondary is a brown dwarf; and a three-star model involving a low-mass eclipsing binary in a hierarchical triple system. We conclude that the latter is the most likely model

Effects of Particle Shape on Growth Dynamics at Edges of Evaporating Colloidal Drops

We study the influence of particle shape on growth processes at the edges of evaporating drops. Aqueous suspensions of colloidal particles evaporate on glass slides, and convective flows during evaporation carry particles from drop center to drop edge, where they accumulate. The resulting particle deposits grow inhomogeneously from the edge in two-dimensions, and the deposition front, or growth line, varies spatio-temporally. Measurements of the fluctuations of the deposition front during evaporation enable us to identify distinct growth processes that depend strongly on particle shape. Sphere deposition exhibits a classic Poisson like growth process; deposition of slightly anisotropic particles, however, belongs to the Kardar-Parisi-Zhang (KPZ) universality class, and deposition of highly anisotropic ellipsoids appears to belong to a third universality class, characterized by KPZ fluctuations in the presence of quenched disorder

Helical Packings and Phase Transformations of Soft Spheres in Cylinders

The phase behavior of helical packings of thermoresponsive microspheres inside glass capillaries is studied as a function of volume fraction. Stable packings with long-range orientational order appear to evolve abruptly to disordered states as particle volume fraction is reduced, consistent with recent hard sphere simulations. We quantify this transition using correlations and susceptibilities of the orientational order parameter psi_6. The emergence of coexisting metastable packings, as well as coexisting ordered and disordered states, is also observed. These findings support the notion of phase transition-like behavior in quasi-1D systems.Comment: 5 pages, with additional 4 pages of supplemental material, accepted to Physical Review E: Rapid Communication

Elasticity-Dependent Self-assembly of Micro-Templated Chromonic Liquid Crystal Films

We explore micropatterned director structures of aqueous lyotropic chromonic liquid crystal (LCLC) films created on square lattice cylindrical-micropost substrates. The structures are manipulated by modulating the LCLC mesophases and their elastic properties via concentration through drying. Nematic LCLC films exhibit preferred bistable alignment along the diagonals of the micropost lattice. Columnar LCLC films, dried from nematics, form two distinct director and defect configurations: a diagonally aligned director pattern with local squares of defects, and an off-diagonal configuration with zig-zag defects. The formation of these states appears to be tied to the relative splay and bend free energy costs of the initial nematic films. The observed nematic and columnar configurations are understood numerically using a Landau-de Gennes free energy model. Among other attributes, the work provide first examples of quasi-2D micropatterning of LC films in the columnar phase and lyotropic LC films in general, and it demonstrates alignment and configuration switching of typically difficult-to-align LCLC films via bulk elastic properties.Comment: 9 pages; 9 figures; accepted for publication in Soft Matte

Cervical preparation for first trimester surgical abortion.

BACKGROUND: Preparing the cervix prior to surgical abortion is intended to make the procedure both easier and safer. Options for cervical preparation include osmotic dilators and pharmacologic agents. Many formulations and regimens are available, and recommendations from professional organizations vary for the use of preparatory techniques in women of different ages, parity or gestational age of the pregnancy. OBJECTIVES: To determine whether cervical preparation is necessary in the first trimester, and if so, which preparatory agent is preferred. SEARCH STRATEGY: We searched Cochrane, Popline, Embase, Medline and Lilacs databases for randomised controlled trials investigating the use of cervical preparatory techniques prior to first trimester surgical abortion. In addition, we hand-searched key references and contacted authors to locate unpublished studies or studies not identified in the database searches. SELECTION CRITERIA: Randomised controlled trials investigating any pharmacologic or mechanical method of cervical preparation, with the exception of nitric oxide donors (the subject of another Cochrane review), administered prior to first trimester surgical abortion were included. Outcome measures must have included the amount of cervical dilation achieved, the procedure duration or difficulty, side-effects, patient satisfaction or adverse events to be included in this review. DATA COLLECTION AND ANALYSIS: Trials under consideration were evaluated by considering whether inclusion criteria were met as well as methodologic quality. Fifty-one studies were included, resulting in 24 different cervical preparation comparisons. Results are reported as odds ratios (OR) for dichotomous outcomes and weighted mean differences for continuous data. MAIN RESULTS: When compared to placebo, misoprostol (400-600 microg given vaginally or sublingually), gemeprost, mifepristone (200 or 600 mg), prostaglandin E and F(2alpha) (2.5 mg administered intracervically) demonstrated larger cervical preparation effects. When misoprostol was compared to gemeprost, misoprostol was more effective in preparing the cervix and was associated with fewer gastrointestinal side-effects. For vaginal administration, administration 2 hours prior was less effective than administration 3 hours prior to the abortion. Compared to oral misoprostol administration, the vaginal route was associated with significantly greater initial cervical dilation and lower rates of side-effects; however, sublingual administration 2-3 hours prior to the procedure demonstrated cervical effects superior to vaginal administration.When misoprostol (600 microg oral or 800 microg vaginal) was compared to mifepristone (200 mg administered 24 hours prior to procedure), misoprostol had inferior cervical preparatory effects. Compared to day-prior laminaria tents, 200 or 400 microg vaginal misoprostol showed no differences in the need for further mechanical dilation or length of the procedure; similarly, the osmotic dilators Lamicel and Dilapan showed no differences in cervical ripening when compared to gemeprost, although gemeprost had cervical effects which were superior to laminaria tents. Older prostaglandin regimens (sulprostone, prostaglandin E(2) andF(2alpha)) were associated with high rates of gastrointestinal side-effects and unplanned pregnancy expulsions. Few studies reported women's satisfaction with cervical preparatory techniques. AUTHORS' CONCLUSIONS: Modern methods of cervical ripening are generally safe, although efficacy and side-effects between methods vary. Reports of adverse events such as cervical laceration or uterine perforation are uncommon overall in this body of evidence and no published study has investigated whether cervical preparation impacts these rare outcomes. Cervical preparation decreases the length of the abortion procedure; this may become increasingly important with increasing gestational age, as mechanical dilation at later gestational ages takes longer and becomes more difficult. These data do not suggest a gestational age where the benefits of cervical dilation outweigh the side-effects, including pain, that women experience with cervical ripening procedures or the prolongation of the time interval before procedure completion. Mifepristone 200 mg, osmotic dilators and misoprostol, 400microg administered either vaginally or sublingually, are the most effective methods of cervical preparation

Medical abortion with mifepristone and vaginal misoprostol between 64 and 70 days' gestation.

ObjectiveTo evaluate outcomes with mifepristone 200 mg orally followed 24-48 h later by misoprostol 800 mcg vaginally for medical abortion at 64-70 days of gestation.Study designWe reviewed electronic databases and medical records for medical abortion cases at 64-70 days' gestation at British Pregnancy Advisory Service clinics in England and Wales from May 2015 through October 2016. Women selected in-office follow-up or self-evaluation of abortion outcome using a checklist along with low-sensitivity urine pregnancy testing. We excluded cases in which we could not locate records and when women did not proceed with medical abortion, did not use misoprostol following mifepristone if abortion had not occurred and did not attend a scheduled follow-up assessment. We analyzed demographic characteristics, treatment outcomes and significant adverse events. We defined treatment success as complete abortion without surgical evacuation and without continuing pregnancy.ResultsOf 2743 cases identified, we could not locate 40 charts and excluded 30 cases, leaving a final sample of 2673. Overall, 2538 (94.9%, 95% CI 94.1-95.8) women had a successful medical abortion. Reasons for failure included continuing pregnancy (n=90, 3.4%, 95% CI 2.7-4.1), retained nonviable pregnancy (n=2, 0.1%, 95% CI 0-0.2) and incomplete abortion (n=43, 1.6%, 95% CI 1.1-2.1). Of those with continuing pregnancies, 81 underwent a uterine aspiration and 9 opted to continue the pregnancy. Thirty-five (1.3%, 95% CI 0.9-1.7) women had significant adverse events; 16 (0.6%, 95% CI 0.3-0.9) underwent an in-hospital aspiration. Pelvic infection (n=4, 0.2%) and transfusion (n=1, 0.03%) occurred rarely.ConclusionMedical abortion from 64 to 70 days with mifepristone and vaginal misoprostol is effective with a low rate of serious adverse events.ImplicationsMedical abortion between 64 and 70 days of gestation may be offered on an outpatient basis using mifepristone and vaginal misoprostol. Service provision without an in-person follow-up is feasible. Not all women with a continuing pregnancy after medical abortion treatment opt to have an aspiration procedure

Decision and function problems based on boson sampling

Boson sampling is a mathematical problem that is strongly believed to be intractable for classical computers, whereas passive linear interferometers can produce samples efficiently. So far, the problem remains a computational curiosity, and the possible usefulness of boson-sampling devices is mainly limited to the proof of quantum supremacy. The purpose of this work is to investigate whether boson sampling can be used as a resource of decision and function problems that are computationally hard, and may thus have cryptographic applications. After the definition of a rather general theoretical framework for the design of such problems, we discuss their solution by means of a brute-force numerical approach, as well as by means of non-boson samplers. Moreover, we estimate the sample sizes required for their solution by passive linear interferometers, and it is shown that they are independent of the size of the Hilbert space.Comment: Close to the version published in PR