Structure and magnetism of the triangular lattice material YbBO3.

YbBO3is a member of the orthoborate family of materials which contains a triangular arrangement of Yb3+ions. Here we study the physical properties of YbBO3with neutron diffraction, inelastic neutron scattering, specific heat, and ac susceptibility measurements. The neutron diffraction measurements confirm that our samples of YbBO3crystallize in the monoclinic space groupC2/c(#15) which contains two crystallographically distinct Yb3+sites decorating a slightly distorted triangular lattice. Heat capacity and ac susceptibility measurements indicate a potential transition to magnetic order at 0.4 K. In agreement with these observations, neutron diffraction measurements at 0.044 K observe magnetic Bragg peaks which can be indexed by a propagation vector of (0 0 1). Although determining a unique spin configuration corresponding to the observed magnetic Bragg peaks is not possible, model refinements indicate that the ordered moments are likely in the range of 0.4-0.9 µBand, notably, require moments on both Yb sites. In addition to the magnetic Bragg peaks, diffuse scattering at lowQis observed indicating that the transition does not correspond to complete long range magnetic order. The two-site picture for YbBO3is further evidenced by the number of crystal field excitations observed by inelastic neutron scattering measurements. Together these results show that YbBO3is a two-site triangular lattice material with signatures of long-range order as well as shorter ranged spin correlations.

CHESS: The future direct geometry spectrometer at the second target station.

CHESS, chopper spectrometer examining small samples, is a planned direct geometry neutron chopper spectrometer designed to detect and analyze weak signals intrinsic to small cross sections (e.g., small mass, small magnetic moments, or neutron absorbing materials) in powders, liquids, and crystals. CHESS is optimized to enable transformative investigations of quantum materials, spin liquids, thermoelectrics, battery materials, and liquids. The broad dynamic range of the instrument is also well suited to study relaxation processes and excitations in soft and biological matter. The 15 Hz repetition rate of the Second Target Station at the Spallation Neutron Source enables the use of multiple incident energies within a single source pulse, greatly expanding the information gained in a single measurement. Furthermore, the high flux grants an enhanced capability for polarization analysis. This enables the separation of nuclear from magnetic scattering or coherent from incoherent scattering in hydrogenous materials over a large range of energy and momentum transfer. This paper presents optimizations and technical solutions to address the key requirements envisioned in the science case and the anticipated uses of this instrument.

Uterine artery embolisation or myomectomy for women with uterine fibroids wishing to avoid hysterectomy: a cost-utility analysis of the FEMME trial.

OBJECTIVES: To assess the cost-effectiveness of uterine artery embolisation (UAE) and myomectomy for women with symptomatic uterine fibroids wishing to avoid hysterectomy. DESIGN: Economic evaluation alongside the FEMME randomised controlled trial. SETTING: 29 UK hospitals. POPULATION: Premenopausal women who had symptomatic uterine fibroids amenable to UAE or myomectomy wishing to avoid hysterectomy. 254 women were randomised to UAE (127) and myomectomy (127). METHODS: A within-trial cost-utility analysis was conducted from the perspective of the UK NHS. MAIN OUTCOME MEASURES: Quality-adjusted life years (QALYs) measured using the EuroQoL EQ-5D-3L, combined with costs to estimate cost-effectiveness over 2 and 4 years of follow-up. RESULTS: Over a 2-year time horizon, UAE was associated with higher mean costs (difference £645; 95% CI -1381 to 2580) and lower QALYs (difference -0.09; 95% CI -0.11 to -0.04) when compared with myomectomy. Similar results were observed over the 4-year time horizon. Thus, UAE was dominated by myomectomy. Results of the sensitivity analyses were consistent with the base case results for both years. Over 2 years, UAE was associated with higher costs (difference £456; 95% CI -1823 to 3164) and lower QALYs (difference -0.06; 95% CI -0.11 to -0.02). CONCLUSIONS: Myomectomy is a cost-effective option for the treatment of uterine fibroids. The differences in costs and QALYs are small. Women should be fully informed and have the option to choose between the two procedures. TWEETABLE ABSTRACT: Fully informed women with uterine fibroids should have a choice between uterine artery embolisation or myomectomy.

Van Hove singularity in the magnon spectrum of the antiferromagnetic quantum honeycomb lattice.

In quantum magnets, magnetic moments fluctuate heavily and are strongly entangled with each other, a fundamental distinction from classical magnetism. Here, with inelastic neutron scattering measurements, we probe the spin correlations of the honeycomb lattice quantum magnet YbCl3. A linear spin wave theory with a single Heisenberg interaction on the honeycomb lattice, including both transverse and longitudinal channels of the neutron response, reproduces all of the key features in the spectrum. In particular, we identify a Van Hove singularity, a clearly observable sharp feature within a continuum response. The demonstration of such a Van Hove singularity in a two-magnon continuum is important as a confirmation of broadly held notions of continua in quantum magnetism and additionally because analogous features in two-spinon continua could be used to distinguish quantum spin liquids from merely disordered systems. These results establish YbCl3 as a benchmark material for quantum magnetism on the honeycomb lattice.

Premature ovarian insufficiency: a toolkit for the primary care physician.

Premature ovarian insufficiency (POI) refers to the loss of ovarian activity before the age of 40 years, which leads to hypoestrogenism and amenorrhea. The diagnosis of POI in a young woman has potentially life-changing physical and emotional consequences for both the patient and her family. Therefore, it is very important that the diagnosis is correct and that it is made in a timely manner. Unfortunately, the diagnosis and therefore the effective treatment of POI are often delayed, which underlines the need for education of the broad medical community on the issue. A panel of menopause experts reviewed and critically appraised the literature, and present: (1) the diagnostic approach to POI, (2) the investigation of the etiology of this condition, (3) the therapeutic strategy regarding both hormone replacement therapy and fertility, and (4) the long-term follow-up and management for ensuring quality of life, as well as urogenital, cardiovascular, bone and mental health. The ultimate goal of this article is to provide a complete toolkit for the primary care physician to have easy access to all the information needed for the optimal management of women with POI, in the context of evidence-based and personalized medicine.HIGHLIGHTSPremature ovarian insufficiency occurs in 1% of the female population of reproductive age, yet the diagnosis is often delayed, with severe physical and emotional consequences for the patient.Primary care physicians should be aware of the possibility of premature ovarian insufficiency in young women presenting with menstrual irregularity.Prompt initiation of hormone replacement therapy ensures quality of life and prevents osteoporosis and cardiovascular disease.Women seeking fertility should be referred to specialists to discuss assisted reproduction options.

The cost-effectiveness of progesterone in preventing miscarriages in women with early pregnancy bleeding: an economic evaluation based on the PRISM trial.

OBJECTIVES: To assess the cost-effectiveness of progesterone compared with placebo in preventing pregnancy loss in women with early pregnancy vaginal bleeding. DESIGN: Economic evaluation alongside a large multi-centre randomised placebo-controlled trial. SETTING: Forty-eight UK NHS early pregnancy units. POPULATION: Four thousand one hundred and fifty-three women aged 16-39 years with bleeding in early pregnancy and ultrasound evidence of an intrauterine sac. METHODS: An incremental cost-effectiveness analysis was performed from National Health Service (NHS) and NHS and Personal Social Services perspectives. Subgroup analyses were carried out on women with one or more and three or more previous miscarriages. MAIN OUTCOME MEASURES: Cost per additional live birth at ≥34 weeks of gestation. RESULTS: Progesterone intervention led to an effect difference of 0.022 (95% CI -0.004 to 0.050) in the trial. The mean cost per woman in the progesterone group was £76 (95% CI -£559 to £711) more than the mean cost in the placebo group. The incremental cost-effectiveness ratio for progesterone compared with placebo was £3305 per additional live birth. For women with at least one previous miscarriage, progesterone was more effective than placebo with an effect difference of 0.055 (95% CI 0.014-0.096) and this was associated with a cost saving of £322 (95% CI -£1318 to £673). CONCLUSIONS: The results suggest that progesterone is associated with a small positive impact and a small additional cost. Both subgroup analyses were more favourable, especially for women who had one or more previous miscarriages. Given available evidence, progesterone is likely to be a cost-effective intervention, particularly for women with previous miscarriage(s). TWEETABLE ABSTRACT: Progesterone treatment is likely to be cost-effective in women with early pregnancy bleeding and a history of miscarriage.

Variation in menopausal vasomotor symptoms outcomes in clinical trials: a systematic review.

BACKGROUND: There is substantial variation in how menopausal vasomotor symptoms are reported and measured among intervention studies. This has prevented meaningful comparisons between treatments and limited data synthesis. OBJECTIVES: To review systematically the outcome reporting and measures used to assess menopausal vasomotor symptoms from randomised controlled trials of treatments. SEARCH STRATEGY: We searched MEDLINE, Embase, and Cochrane Central Register of Controlled Trials from inception to May 2018. SELECTION CRITERIA: Randomised controlled trials with a primary outcome of menopausal vasomotor symptoms in women and a sample size of at least 20 women per study arm. DATA COLLECTION AND ANALYSIS: Data about study characteristics, primary vasomotor-related outcomes and methods of measuring them. MAIN RESULTS: The search identified 5591 studies, 214 of which were included. Forty-nine different primary reported outcomes were identified for vasomotor symptoms and 16 different tools had been used to measure these outcomes. The most commonly reported outcomes were frequency (97/214), severity (116/214), and intensity (28/114) of vasomotor symptoms or a composite of these outcomes (68/214). There was little consistency in how the frequency and severity/intensity of vasomotor symptoms were defined. CONCLUSIONS: There is substantial variation in how menopausal vasomotor symptoms have been reported and measured in treatment trials. Future studies should include standardised outcome measures which reflect the priorities of patients, clinicians, and researchers. This is most effectively achieved through the development of a Core Outcome Set. This systematic review is the first step towards development of a Core Outcome Set for menopausal vasomotor symptoms. TWEETABLE SUMMARY: Menopausal hot flushes and night sweats have been reported in 49 different ways in clinical research. A core outcome set is urgently required.

The evolution of the human menopause.

The females of most species die soon after ceasing to reproduce, their purpose in life being to ensure survival of their kin. Human females may live more than one-third of their lives after they cease to reproduce, a property shared by few species, one of which is Orca whales. Orcas have been extensively studied because families live together in stable units or pods and individual whales have distinctive markings, enabling them to be identified. The females survive long after the menopause, one possible reason for this being that the older females provide a survival advantage since they are seen to lead the pods more often than younger females or males, thus providing a survival advantage in times of food shortage. The female lifespan is increasing in most countries worldwide, principally due to decreased infection and maternal mortality. Women are now more active through middle and into older age. Whatever sort of life they wish to lead, women need to be as fit as possible to facilitate healthy aging. Chronic diseases that affect millions of women are cardiovascular disease, osteoporosis, cancer, and dementia. The incidence of all these is increased by obesity, the prevention of which is a major challenge in our society. Hormone therapy may have a place for some women but for many others taking control of their health by lifestyle intervention is a major contributor to disease prevention. It is our duty as doctors to encourage this at every opportunity to help all women live a fruitful and healthy old age.

Tomonaga-Luttinger liquid behavior and spinon confinement in YbAlO3.

Low dimensional quantum magnets are interesting because of the emerging collective behavior arising from strong quantum fluctuations. The one-dimensional (1D) S = 1/2 Heisenberg antiferromagnet is a paradigmatic example, whose low-energy excitations, known as spinons, carry fractional spin S = 1/2. These fractional modes can be reconfined by the application of a staggered magnetic field. Even though considerable progress has been made in the theoretical understanding of such magnets, experimental realizations of this low-dimensional physics are relatively rare. This is particularly true for rare-earth-based magnets because of the large effective spin anisotropy induced by the combination of strong spin-orbit coupling and crystal field splitting. Here, we demonstrate that the rare-earth perovskite YbAlO3 provides a realization of a quantum spin S = 1/2 chain material exhibiting both quantum critical Tomonaga-Luttinger liquid behavior and spinon confinement-deconfinement transitions in different regions of magnetic field-temperature phase diagram.

Behavior of the breathing pyrochlore lattice Ba3Yb2Zn5O11 in applied magnetic field.

The breathing pyrochlore lattice material Ba3Yb2Zn5O11 exists in the nearly decoupled limit, in contrast to most other well-studied breathing pyrochlore compounds. As a result, it constitutes a useful platform to benchmark theoretical calculations of exchange interactions in insulating Yb3+ magnets. Here we study Ba3Yb2Zn5O11 at low temperatures in applied magnetic fields as a further probe of the physics of this model system. Experimentally, we consider the behavior of polycrystalline samples of Ba3Yb2Zn5O11 with a combination of inelastic neutron scattering and heat capacity measurements down to 75 mK and up to fields of 10 T. Consistent with previous work, inelastic neutron scattering finds a level crossing near 3 T, but no significant dispersion of the spin excitations is detected up to the highest applied fields. Refinement of the theoretical model previously determined at zero field can reproduce much of the inelastic neutron scattering spectra and specific heat data. A notable exception is a low temperature peak in the specific heat at ∼0.1 K. This may indicate the scale of interactions between tetrahedra or may reflect undetected disorder in Ba3Yb2Zn5O11.

Abnormal uterine bleeding in perimenopause.

Abnormal uterine bleeding is one of the commonest presenting complaints encountered in a gynecologist's office or primary-care setting. The wider availability of diagnostic tools has allowed prompt diagnosis and treatment of an increasing number of menstrual disorders in an office setting. This White Paper reviews the advantages and disadvantages of transvaginal ultrasound, blind endometrial sampling and diagnostic hysteroscopy. Once a proper diagnosis has been established, appropriate therapy may be embarked upon. Fortunately, only a minority of such patients will have premalignant or malignant disease. When bleeding is sufficient to cause severe anemia or even hypovolemia, prompt intervention is called for. In most of the cases, however, the abnormal uterine bleeding will be disquieting to the patient and significantly affect her 'quality of life'. Sometimes, reassurance and expectant management will be sufficient in such patients. Overall, however, in cases of benign disease, some intervention will be required. The use of oral contraceptive pills especially those with a short hormone-free interval, the insertion of the levonorgestrel intrauterine system, the incorporation of newer medical therapies including antifibrinolytic drugs and selective progesterone receptor modulators and minimally invasive treatments have made outpatient therapy increasingly effective. For others, operative hysteroscopy and endometrial ablation are proven therapeutic tools to provide both long- and short-term relief of abnormal uterine bleeding, thus avoiding, or deferring, hysterectomy.

Spin-Orbit Coupling Controlled J=3/2 Electronic Ground State in 5d

Entanglement of spin and orbital degrees of freedom drives the formation of novel quantum and topological physical states. Here we report resonant inelastic x-ray scattering measurements of the transition metal oxides Ca_{3}LiOsO_{6} and Ba_{2}YOsO_{6}, which reveals a dramatic spitting of the t_{2g} manifold. We invoke an intermediate coupling approach that incorporates both spin-orbit coupling and electron-electron interactions on an even footing and reveal that the ground state of 5d^{3}-based compounds, which has remained elusive in previously applied models, is a novel spin-orbit entangled J=3/2 electronic ground state. This work reveals the hidden diversity of spin-orbit controlled ground states in 5d systems and introduces a new arena in the search for spin-orbit controlled phases of matter.

The menopausal hot flush: a review.

The hot flush is the most characteristic and often the most distressing symptom of the menopause. It is a unique feature and yet the mechanism and health implications are still not fully understood. This review summarizes some of the current thoughts on factors contributing to flushing, the physiological, vascular and neuroendocrine changes associated with flushing and the possible cardiovascular and other health implications for women experiencing hot flushes. Therapy is not discussed.

Vasomotor symptoms resulting from natural menopause: a systematic review and network meta-analysis of treatment effects from the National Institute for Health and Care Excellence guideline on menopause.

BACKGROUND: Vasomotor symptoms (VMSs) are the hallmarks of menopause, occurring in approximately 75% of postmenopausal women in the UK, and are severe in 25%. OBJECTIVES: To identify which treatments are most clinically effective for the relief of VMSs for women in natural menopause without hysterectomy. SEARCH STRATEGY: English publications in MEDLINE, Embase, and The Cochrane Library up to 13 January 2015 were searched. SELECTION CRITERIA: Randomised controlled trials (RCTs) of treatments for women with a uterus for the outcomes of frequency of VMSs (up to 26 weeks), vaginal bleeding, and discontinuation. DATA COLLECTION AND ANALYSIS: Bayesian network meta-analysis (NMA) using mean ratios (MRs) and odd ratios (ORs). MAIN RESULTS: Across the three networks, 47 RCTs of 16 treatment classes (n = 8326 women) were included. When compared with placebo, transdermal estradiol and progestogen (O+P) had the highest probability of being the most effective treatment for VMS relief (69.8%; MR 0.23; 95% credible interval, 95% CrI 0.09-0.57), whereas oral O+P was ranked lower than transdermal O+P, although oral and transdermal O+P were no different for this outcome (MR 2.23; 95% CrI 0.7-7.1). Isoflavones and black cohosh were more effective than placebo, although not significantly better than O+P. Not only were selective serotonin reuptake inhibitors (SSRIs) or serotonin-norepinephrine reuptake inhibitors (SNRIs) found to be ineffective in relieving VMSs, but they also had significantly higher odds of discontinuation than placebo. Limited data were available for bleeding, therefore no conclusions could be made. CONCLUSION: For women who have not undergone hysterectomy, transdermal O+P was the most effective treatment for VMS relief. TWEETABLE ABSTRACT: Which treatment best relieves menopause flushes? Results from the #NICE guideline network meta-analysis.

Anisotropic Exchange within Decoupled Tetrahedra in the Quantum Breathing Pyrochlore Ba_{3}Yb_{2}Zn_{5}O_{11}.

The low energy spin excitation spectrum of the breathing pyrochlore Ba_{3}Yb_{2}Zn_{5}O_{11} has been investigated with inelastic neutron scattering. Several nearly resolution limited modes with no observable dispersion are observed at 250 mK while, at elevated temperatures, transitions between excited levels become visible. To gain deeper insight, a theoretical model of isolated Yb^{3+} tetrahedra parametrized by four anisotropic exchange constants is constructed. The model reproduces the inelastic neutron scattering data, specific heat, and magnetic susceptibility with high fidelity. The fitted exchange parameters reveal a Heisenberg antiferromagnet with a very large Dzyaloshinskii-Moriya interaction. Using this model, we predict the appearance of an unusual octupolar paramagnet at low temperatures and speculate on the development of intertetrahedron correlations.

Spin-orbit-driven magnetic structure and excitation in the 5d pyrochlore Cd2Os2O7.

Much consideration has been given to the role of spin-orbit coupling (SOC) in 5d oxides, particularly on the formation of novel electronic states and manifested metal-insulator transitions (MITs). SOC plays a dominant role in 5d(5) iridates (Ir(4+)), undergoing MITs both concurrent (pyrochlores) and separated (perovskites) from the onset of magnetic order. However, the role of SOC for other 5d configurations is less clear. For example, 5d(3) (Os(5+)) systems are expected to have an orbital singlet with reduced effective SOC. The pyrochlore Cd2Os2O7 nonetheless exhibits a MIT entwined with magnetic order phenomenologically similar to pyrochlore iridates. Here, we resolve the magnetic structure in Cd2Os2O7 with neutron diffraction and then via resonant inelastic X-ray scattering determine the salient electronic and magnetic energy scales controlling the MIT. In particular, SOC plays a subtle role in creating the electronic ground state but drives the magnetic order and emergence of a multiple spin-flip magnetic excitation.

Proximate Kitaev quantum spin liquid behaviour in a honeycomb magnet.

Quantum spin liquids (QSLs) are topological states of matter exhibiting remarkable properties such as the capacity to protect quantum information from decoherence. Whereas their featureless ground states have precluded their straightforward experimental identification, excited states are more revealing and particularly interesting owing to the emergence of fundamentally new excitations such as Majorana fermions. Ideal probes of these excitations are inelastic neutron scattering experiments. These we report here for a ruthenium-based material, α-RuCl3, continuing a major search (so far concentrated on iridium materials) for realizations of the celebrated Kitaev honeycomb topological QSL. Our measurements confirm the requisite strong spin-orbit coupling and low-temperature magnetic order matching predictions proximate to the QSL. We find stacking faults, inherent to the highly two-dimensional nature of the material, resolve an outstanding puzzle. Crucially, dynamical response measurements above interlayer energy scales are naturally accounted for in terms of deconfinement physics expected for QSLs. Comparing these with recent dynamical calculations involving gauge flux excitations and Majorana fermions of the pure Kitaev model, we propose the excitation spectrum of α-RuCl3 as a prime candidate for fractionalized Kitaev physics.