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Stem cells give rise to the entirety of cells within an organ. Maintaining stem cell identity and coordinately regulating stem cell divisions is crucial for proper development. In plants, mobile proteins, such as WUSCHEL-RELATED HOMEOBOX 5 (WOX5) and SHORTROOT (SHR), regulate divisions in the root stem cell niche. However, how these proteins coordinately function to establish systemic behaviour is not well understood. We propose a non-cell autonomous role for WOX5 in the cortex endodermis initial (CEI) and identify a regulator, ANGUSTIFOLIA (AN3)/GRF-INTERACTING FACTOR 1, that coordinates CEI divisions. Here, we show with a multi-scale hybrid model integrating ordinary differential equations (ODEs) and agent-based modeling that quiescent center (QC) and CEI divisions have different dynamics. Specifically, by combining continuous models to describe regulatory networks and agent-based rules, we model systemic behaviour, which led us to predict cell-type-specific expression dynamics of SHR, SCARECROW, WOX5, AN3 and CYCLIND6;1, and experimentally validate CEI cell divisions. Conclusively, our results show an interdependency between CEI and QC divisions.
The southern pine beetle, Dendroctonus frontalis Zimmermann (Coleoptera: Curculionidae: Scolytinae), is among the most destructive bark beetle pests of pines (Pinaceae) of the southeast and mid-Atlantic United States of America, Mexico, and Central America. Numerous volatile compounds can stimulate or reduce attraction of the beetle, but efforts to incorporate these into effective, practical technologies for pest management have yielded mixed results. Attractants have been incorporated into lures used in monitoring traps that are employed operationally to forecast outbreaks and detect emerging populations. The attraction inhibitor, verbenone, shows efficacy for suppressing southern pine beetle infestations but has not yet been adopted operationally. No effective semiochemical tree protectant has been developed for the beetle. We discuss complexities in the chemical ecology of the beetle that likely have impeded research and development of semiochemical management tools, and we describe basic science gaps that may hinder further progress if not addressed. We also report some supporting, original experimental data indicating (1) that a verbenone device can inhibit the beetle’s response to sources of attractant in a radius of at least several metres, (2) similar olfactory responses by the beetle to both enantiomers of verbenone, and (3) that pheromone background can cause conflicting results in semiochemical field tests.
Optical tracking systems typically trade off between astrometric precision and field of view. In this work, we showcase a networked approach to optical tracking using very wide field-of-view imagers that have relatively low astrometric precision on the scheduled OSIRIS-REx slingshot manoeuvre around Earth on 22 Sep 2017. As part of a trajectory designed to get OSIRIS-REx to NEO 101955 Bennu, this flyby event was viewed from 13 remote sensors spread across Australia and New Zealand to promote triangulatable observations. Each observatory in this portable network was constructed to be as lightweight and portable as possible, with hardware based off the successful design of the Desert Fireball Network. Over a 4-h collection window, we gathered 15 439 images of the night sky in the predicted direction of the OSIRIS-REx spacecraft. Using a specially developed streak detection and orbit determination data pipeline, we detected 2 090 line-of-sight observations. Our fitted orbit was determined to be within about 10 km of orbital telemetry along the observed 109 262 km length of OSIRIS-REx trajectory, and thus demonstrating the impressive capability of a networked approach to Space Surveillance and Tracking.
Gravitational waves from coalescing neutron stars encode information about nuclear matter at extreme densities, inaccessible by laboratory experiments. The late inspiral is influenced by the presence of tides, which depend on the neutron star equation of state. Neutron star mergers are expected to often produce rapidly rotating remnant neutron stars that emit gravitational waves. These will provide clues to the extremely hot post-merger environment. This signature of nuclear matter in gravitational waves contains most information in the 2–4 kHz frequency band, which is outside of the most sensitive band of current detectors. We present the design concept and science case for a Neutron Star Extreme Matter Observatory (NEMO): a gravitational-wave interferometer optimised to study nuclear physics with merging neutron stars. The concept uses high-circulating laser power, quantum squeezing, and a detector topology specifically designed to achieve the high-frequency sensitivity necessary to probe nuclear matter using gravitational waves. Above 1 kHz, the proposed strain sensitivity is comparable to full third-generation detectors at a fraction of the cost. Such sensitivity changes expected event rates for detection of post-merger remnants from approximately one per few decades with two A+ detectors to a few per year and potentially allow for the first gravitational-wave observations of supernovae, isolated neutron stars, and other exotica.
Solidification processing offers the first opportunity to control microstructure, properties, and performance in metallic alloy components. Until recently, microstructural evaluations were limited to post-solidification characterization by destructive methods. We review the development of time-resolved, in situ imaging techniques capable of capturing solid–liquid interfacial evolution in metallic alloys with high spatial and temporal resolution under diverse solidification conditions relevant for applications ranging from conventional directional solidification, crystal growth, and casting, to welding and additive manufacturing. These experiments enable direct visualization of transient behaviors that would otherwise remain unknown, uniquely providing insights into the physics that impact microstructure and defect development, and strategies for microstructural control and defect mitigation. Understanding microstructural evolution and the characteristics that form under various solidification conditions is essential for the development of multiscale, experimentally informed predictive modeling. This is highlighted by solidification simulations that utilize in situ measurements of solidification dynamics from state-of-the-art experimental techniques.
Out-of-network air ambulance bills are a pernicious and financially devastating type of surprise medical bill. Courts have broadly interpreted the Airline Deregulation Act to preempt most state attempts to regulate air ambulance billing abuses, so a federal solution is ultimately needed. However, in the absence of a federal fix, states have experimented with a variety of approaches that may survive preemption and provide some protections for their citizens
Advanced imaging techniques are enhancing research capacity focussed on the developmental origins of adult health and disease (DOHaD) hypothesis, and consequently increasing awareness of future health risks across various subareas of DOHaD research themes. Understanding how these advanced imaging techniques in animal models and human population studies can be both additively and synergistically used alongside traditional techniques in DOHaD-focussed laboratories is therefore of great interest. Global experts in advanced imaging techniques congregated at the advanced imaging workshop at the 2019 DOHaD World Congress in Melbourne, Australia. This review summarizes the presentations of new imaging modalities and novel applications to DOHaD research and discussions had by DOHaD researchers that are currently utilizing advanced imaging techniques including MRI, hyperpolarized MRI, ultrasound, and synchrotron-based techniques to aid their DOHaD research focus.
Inflammation is a major cause of chronic diseases. Several studies have investigated the effects of soya intake on inflammatory biomarkers; however, the results are equivocal. The aim of this study was to conduct a systematic review and meta-analysis of clinical trials that evaluated the effect of soya consumption on inflammatory biomarkers. Medline, Scopus, ISI Web of Science and Google Scholar were systematically searched, up to and including May 2020, for clinical trials that evaluated the effects of soya and soya products on TNF-α, IL-6, IL-2, IL-1β and interferon γ (IFN-γ) in adults. A random effects method was used to calculate overall effects, and subgroup analyses were performed to discern probable sources of inter-study heterogeneity. A total of twenty-eight clinical trials were included. Although soya consumption reduced TNF-α (Hedges’ g = –0·28; 95 % CI –0·49, –0·07), it had no significant effect on IL-6 (Hedges’ g = 0·07, 95 % CI –0·14, 0·28), IL-2 (mean difference (MD) = –1·38 pg/ml; 95 % CI –3·07, 0·31), IL-1β (MD = –0·02 pg/ml; 95 % CI –0·08, 0·03) and IFN-γ (MD = 1685·82 pg/ml; 95 % CI –1604·86, 4976·50). Subgroup analysis illustrated a reduction in TNF-α in parallel designed studies, at dosages ≥100 mg of isoflavones, and in unhealthy subjects. The present study showed that high doses of isoflavones in unhealthy subjects may yield beneficial effects on TNF-α.
Over the ages, clinicians have tried to decipher the mysteries of the human body by exploiting natural openings to examine the internal aspects of organs. Since as far back as Hippocrates, a variety of instruments have been employed to achieve this. The simplest form of instrument is a speculum, used to augment natural openings and allow ambient light to illuminate the inner aspect of organs for inspection by the naked eye. While this may be helpful for examining the nostrils or the vagina, for example, it is not an adequate approach for a well-concealed organ such as the uterus. Accurate endoscopic examination of the endometrial cavity, i.e. hysteroscopy, requires the transmission of light into and out of a cavity. Since the endometrial cavity is a potential space, collapsed in the natural state, a distension medium is required to expand the field of vision.
Endometrial ablation (EA) is a minimally invasive surgical intervention that aims to reduce heavy menstrual bleeding (HMB) by destroying functionally active endometrial glands within the endometrium and the superficial myometrium, including the deep basal glands. To prevent regeneration and stop menstruation this destruction should be to a depth of 5 mm. In the past, destruction of the endometrium required an operating hysteroscope. Endometrial tissue was either removed using an electrical cutting loop or destroyed by applying thermal energy to induce necrosis using an electrical ‘rollerball’ or laser fibre. These first-generation techniques have largely been superseded by second-generation techniques that comprise semi-automated global ablative systems using a variety of energy sources to thermally ablate the endometrium. These systems require less operator skill, are less likely to require general anaesthesia, are quicker to perform and offer enhanced safety with no loss in effectiveness.
Endometrial polyps are localised overgrowths of endometrial tissue that can occur anywhere in the uterine cavity. They contain variable amounts of glands, stroma and blood vessels that are covered by a layer of endometrium. Most commonly they are attached to the uterus by an elongated pedicle (pedunculated), but they may also have a large flat base (sessile). They range in size from a few millimetres to several centimetres (Figure 10.1).
Uterine fibroids or leiomyomas are solid, invariably benign tumours of uterine smooth muscle and connective tissue. The prevalence varies according to the population studied, but is estimated to be 25% in a general female population of reproductive age, although rates of up to 70% have also been reported [1–6]. Fibroids that encroach beyond the myometrium into the uterine cavity are referred to as submucosal, submucous or intracavity, and may account for up to 10% of all fibroids . They are thought to be associated with abnormal uterine bleeding and reproductive failure. The development of endoscopy has allowed removal of submucosal fibroids under direct vision, hysteroscopic myomectomy, which avoids the need for laparotomy or crude, blind intrauterine techniques.
This chapter covers the process of performing hysteroscopy, paying close attention to optimising patient comfort and maximising the effectiveness of the procedure. Tips are provided for successfully inserting the device and visualising the entire uterine cavity. The possible settings for performing a hysteroscopic investigation are outlined, with suggestions as to which setting may suit an individual patient. Oral anticoagulants have changed in recent years and the effect they may have on patients attending hysteroscopy clinics is discussed, with advice about how to avoid and manage excessive vaginal bleeding.
Heinrich Fritsch reported the first case of intrauterine adhesions (IUAs) at the end of the nineteenth century. Since 1948, a series of papers on this condition have been published by Joseph G. Asherman, which describe the frequency, aetiology and symptoms of IUA
Hysteroscopy is safe and effective and can greatly reduce morbidity and enhance recovery compared with conventional open procedures. Furthermore, it can minimise the inherent risks of general anaesthesia and hospital admissions because many hysteroscopic procedures can now be delivered in non-anaesthetised women in an outpatient setting. The overall complication rate of hysteroscopic intervention is estimated to be less than 1% [1, 2], of which half is due to serious complications, namely fluid overload, uterine perforation and upper genital tract haemorrhage. Complications occur during access and entry into the uterine cavity or during the diagnostic or operative procedure. Complication rates are higher with operative hysteroscopy (0.95%) compared with purely diagnostic procedures (0.13%) . These risks are highest with more complex hysteroscopic surgery such as myomectomy and adhesiolysis and lowest with purely diagnostic procedures.
Hysteroscopy can be used to diagnose endometrial and structural cavity pathologies associated with abnormal uterine bleeding (AUB) and reproductive failure. Optimal interpretation of hysteroscopic findings requires an understanding of the limitations of the technology and incorporation of information obtained from the preceding clinical history and examination. Ideally, hysteroscopy should be avoided during the menstrual period, as the obtained views are likely to be compromised. Although normal endometrial appearances during the secretory phase could potentially be misinterpreted (e.g. as polyps or hyperplastic endometrium), with experience the likelihood of this is small, and so timing the procedure to coincide with the proliferative phase of the menstrual cycle is not necessary or indeed practical
One of the fundamental maxims of surgery is to work with excellent visualisation of the operative field. The dark, inaccessible nature of the uterine cavity has led to procedures in this environment being conducted ‘blindly’, flying in the face of the surgical axiom of good visualisation. Dilatation and curettage, or ‘D&C’, was the defining procedure of gynaecology for the diagnosis and treatment of abnormal uterine bleeding and miscarriage.