Torsion points and the Lattes family

We give a dynamical proof of a result of Masser and Zannier [MZ2, MZ3] about torsion points on the Legendre family of elliptic curves. Our methods also treat points of small height. A key ingredient is the arithmetic equidistribution theorem on $\mathbb{P}^1$ of Baker-Rumely, Chambert-Loir, and Favre-Rivera-Letelier. Torsion points on the elliptic curve coincide with preperiodic points for the degree-4 Lattes family of rational functions. Our main new results concern properties of the bifurcation measures for this Lattes family associated to marked points.Comment: Theorem 1.3 now states the strongest form of the main theorem, the result of combining our methods with the conclusions of Masser-Zannier, for rational points with complex coefficients. To appear, American Journal of Mat

Iterative forcing and hyperimmunity in reverse mathematics

The separation between two theorems in reverse mathematics is usually done by constructing a Turing ideal satisfying a theorem P and avoiding the solutions to a fixed instance of a theorem Q. Lerman, Solomon and Towsner introduced a forcing technique for iterating a computable non-reducibility in order to separate theorems over omega-models. In this paper, we present a modularized version of their framework in terms of preservation of hyperimmunity and show that it is powerful enough to obtain the same separations results as Wang did with his notion of preservation of definitions.Comment: 15 page

Are health facilities well equipped to provide basic quality childbirth services under the free maternal health policy? Findings from rural Northern Ghana

© 2018 The Author(s). Background: Basic inputs and infrastructure including drugs, supplies, equipment, water and electricity are required for the provision of quality care. In the era of the free maternal health policy in Ghana, it is unclear if such basic inputs are readily accessible in health facilities. The study aimed to assess the availability of basic inputs including drugs, supplies, equipment and emergency transport in health facilities. Women and health providers' views on privacy and satisfaction with quality of care were also assessed. Methods: The study used a convergent parallel mixed methods in one rural municipality in Ghana, Kassena-Nankana. A survey among facilities (n = 14) was done. Another survey was carried out among women who gave birth in health facilities only (n = 353). A qualitative component involved focus group discussions (FGDs) with women (n = 10) and in-depth interviews (IDIs) with midwives and nurses (n = 25). Data were analysed using descriptive statistics for the quantitative study, while the qualitative data were recorded, transcribed, read and coded using themes. Results: The survey showed that only two (14%) out of fourteen facilities had clean water, and five (36%) had electricity. Emergency transport for referrals was available in only one (7%) facility. Basic drugs, supplies, equipment and infrastructure especially physical space were inadequate. Rooms used for childbirth in some facilities were small and used for multiple purposes. Eighty-nine percent (n = 314) of women reported lack of privacy during childbirth and this was confirmed in the IDIs. Despite this, 77% of women (n = 272) were very satisfied or satisfied with quality of care for childbirth which was supported in the FGDs. Reasons for women's satisfaction included the availability of midwives to provide childbirth services and to have follow-up homes visits. Some midwives were seen to be patient and empathetic. Providers were not satisfied due to health system challenges. Conclusion: Government should dedicate more resources to the provision of essential inputs for CHPS compounds providing maternal health services. Health management committees should also endeavour to play an active role in the management of health facilities to ensure efficiency and accountability. These would improve quality service provision and usage, helping to achieve universal health coverage

The implementation of the free maternal health policy in rural Northern Ghana: Synthesised results and lessons learnt

© 2018 The Author(s). Objective: A free maternal health policy was implemented under Ghana's National Health Insurance Scheme to promote the use of maternal health services. Under the policy, women are entitled to free services throughout pregnancy and at childbirth. A mixed methods study involving women, providers and insurance managers was carried out in the Kassena-Nankana municipality of Ghana. It explored the affordability, availability, acceptability and quality of services. In this manuscript, we present synthesised results categorised as facilitators and barriers to access as well as lessons learnt (implications). Results: Reasonable waiting times, cleanliness of facilities as well as good interpersonal relationships with providers were the facilitators to access. Barriers included out of pocket payments, lack of, or inadequate supply of drugs and commodities, equipment, water, electricity and emergency transport. Four lessons (implications) were identified. Firstly, out of pocket payments persisted. Secondly, the health system was not strengthened before implementing the free maternal health policy. Thirdly, lower level facilities were poorly resourced. Finally, the lack of essential inputs and infrastructure affected quality of care and therefore, access to care. It is suggested that the Government of Ghana, the Health Insurance Scheme and other stakeholders improve the provision of resources to facilities

The operations of the free maternal care policy and out of pocket payments during childbirth in rural Northern Ghana

© 2017, The Author(s). Background: To promote skilled attendance at births and reduce maternal deaths, the government of Ghana introduced the free maternal care policy under the National Health Insurance Scheme (NHIS) in 2008. The objective is to eliminate financial barriers associated with the use of services. But studies elsewhere showed that out of pocket (OOP) payments still exist in the midst of fee exemptions. The aim of this study was to estimate OOP payments and the financial impact on women during childbirth in one rural and poor area of Northern Ghana; the Kassena-Nankana municipality. Costs were taken from the perspective of women. Methods: Quantitative and qualitative data collection techniques were used in a convergent parallel mixed methods study. The study used structured questionnaire (n = 353) and focus group discussions (FGDs =7) to collect data from women who gave birth in health facilities. Quantitative data from the questionnaire were analysed, using descriptive statistics. Qualitative data from the FGDs were recorded, transcribed and analysed to determine common themes. Results: The overall mean OOP payments during childbirth was GH¢33.50 (US$17), constituting 5.6% of the average monthly household income. Over one-third (36%, n = 145) of women incurred OOP payments which exceeded 10% of average monthly household income (potentially catastrophic). Sixty-nine percent (n = 245) of the women perceived that the NHIS did not cover all expenses incurred during childbirth; which was confirmed in the FGDs. Both survey and FGDs demonstrated that women made OOP payments for drugs and other supplies. The FGDs showed women bought disinfectants, soaps, rubber pads and clothing for newborns as well. Seventy-five percent (n = 264) of the women used savings, but 19% had to sell assets to finance the payments; this was supported in the FGDs. Conclusion: The NHIS policy has not eliminated financial barriers associated with childbirth which impacts the welfare of some women. Women continued to make OOP payments, largely as a result of a delay in reimbursement by the NHIS. There is need to re-examine the reimbursement system in order to prevent shortage of funding to health facilities and thus encourage skilled attendance for the reduction of maternal deaths as well as the achievement of universal health coverage

Has the free maternal health policy eliminated out of pocket payments for maternal health services? Views of women, health providers and insurance managers in Northern Ghana

© 2018 Dalinjong et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Introduction The free maternal health policy was implemented in Ghana in 2008 under the National Health Insurance Scheme (NHIS). The policy sought to eliminate out of pocket (OOP) payments and enhance the utilisation of maternal health services. It is unclear whether the policy had altered OOP payments for services. The study explored views on costs and actual OOP payments during pregnancy. The source of funding for payments was also explored. Methods A convergent parallel mixed methods design, involving quantitative and qualitative data collection approaches. The study was set in the Kassena-Nankana municipality, a rural area in Ghana. Women (n = 406) who utilised services during pregnancy were surveyed. Also, 10 focus groups discussions (FGDs) were held with women who used services during pregnancy as well as 28 in-depth interviews (IDIs) with midwives/nurses (n = 25) and insurance managers/directors (n = 3). The survey was analysed using descriptive statistics, focussing on costs from the women’s perspective. Qualitative data were audio recorded, transcribed and translated verbatim into English where necessary. The transcripts were read and coded into themes and sub-themes. Results The NHIS did not cover all expenses in relation to maternal health services. The overall mean for OOP cost during pregnancy was GH¢17.50 (US$8.60). Both FGDs and IDIs showed that women especially paid for drugs and ultrasound scan services. Sixty-five percent of the women used savings, whilst twenty-two percent sold assets to meet the OOP cost. Some women were unable to afford payments due to poverty and had to forgo treatment. Participants called for payments to be eliminated and for the NHIS to absorb the cost of emergency referrals. All participants admitted the benefits of the policy. Conclusion Women needed to make payments despite the policy. Measures should be put in place to eliminate payments to enable all women to receive services and promote universal health coverage

Fast, Non-Contact, Wafer-Scale, Atomic Layer Resolved Imaging of 2D Materials by Ellipsometric Contrast Micrography

Adequate characterisation and quality control of atomically thin layered materials (2DM) has become a serious challenge particularly given the rapid advancements in their large area manufacturing and numerous emerging industrial applications with different substrate requirements. Here, we focus on ellipsometric contrast micrography (ECM), a fast intensity mode within spectroscopic imaging ellipsometry, and show that it can be effectively used for non-contact, large area characterisation of 2DM to map coverage, layer number, defects and contamination. We demonstrate atomic layer resolved, quantitative mapping of chemical vapour deposited graphene layers on Si/SiO2-wafers, but also on rough Cu catalyst foils, highlighting that ECM is applicable to all application relevant substrates. We discuss the optimisation of ECM parameters for high throughput characterisation. While the lateral resolution can be less than 1 µm, we particularly explore fast scanning and demonstrate imaging of a 4’’ graphene wafer in 47 min at 10 µm lateral resolution, i.e. an imaging speed of 1.7 cm2/min. Furthermore, we show ECM of mono-layer hexagonal BN (h-BN) and of h-BN/graphene bilayers, highlighting that ECM is applicable to a wide range of 2D layered structures that have previously been very challenging to characterise and thereby fills an important gap in 2DM metrology

Steady dark solitary flexural gravity waves

The nonlinear Schrödinger (NLS) equation describes the modulational limit of many surface water wave problems. Dark solitary waves of the NLS equation asymptote to a constant in the far field and have a localized decrease to zero amplitude at the origin, corresponding to water wave solutions that asymptote to a uniform periodic Stokes wave in the far field and decreasing oscillations near the origin. It is natural to ask whether these dark solitary waves can be found in the irrotational Euler equations. In this paper, we find such solutions in the context of flexural-gravity waves, which are often used as a model for waves in ice-covered water. This is a situation in which the NLS equation predicts steadily travelling dark solitons. The solution branches of dark solitons are continued, and one branch leads to fully localized solutions at large amplitudes

STORMy Interactions: Gaze and the Modulation of Mimicry in Adults on the Autism Spectrum

Mimicry involves unconsciously imitating the actions of others and is a powerful and ubiquitous behavior in social interactions. There has been a long debate over whether mimicry is abnormal in people with autism spectrum conditions (ASC) and what the causes of any differences might be. Wang and Hamilton's (2012) social top-down response modulation (STORM) model proposed that people with ASC can and do mimic but, unlike neurotypical participants, fail to modulate their mimicry according to the social context. This study used an established mimicry paradigm to test this hypothesis. In neurotypical participants, direct gaze specifically enhanced congruent hand actions as previously found; in the ASC sample, direct gaze led to faster reaction times in both congruent and incongruent movements. This result shows that mimicry is intact in ASC, but is not socially modulated by gaze, as predicted by STORM

Electrostatic Turbulence and Debye-scale Structures in Collisionless Shocks

We present analysis of more than 100 large-amplitude bipolar electrostatic structures in a quasi-perpendicular supercritical Earth's bow shock crossing, measured by the Magnetospheric Multiscale spacecraft. The occurrence of the bipolar structures is shown to be tightly correlated with magnetic field gradients in the shock transition region. The bipolar structures have negative electrostatic potentials and spatial scales of a few Debye lengths. The bipolar structures propagate highly oblique to the shock normal with velocities (in the plasma rest frame) of the order of the ion-acoustic velocity. We argue that the bipolar structures are ion phase space holes produced by the two-stream instability between incoming and reflected ions. This is the first identification of the ion two-stream instability in collisionless shocks