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Universal control of multiple qubits-the ability to entangle qubits and to perform arbitrary individual qubit operations1-is a fundamental resource for quantum computing2, simulation3 and networking4. Qubits realized in trapped atomic ions have shown the highest-fidelity two-qubit entangling operations5-7 and single-qubit rotations8 so far. Universal control of trapped ion qubits has been separately demonstrated using tightly focused laser beams9-12 or by moving ions with respect to laser beams13-15, but at lower fidelities. Laser-free entangling methods16-20 may offer improved scalability by harnessing microwave technology developed for wireless communications, but so far their performance has lagged the best reported laser-based approaches. Here we demonstrate high-fidelity laser-free universal control of two trapped-ion qubits by creating both symmetric and antisymmetric maximally entangled states with fidelities of [Formula: see text] and [Formula: see text], respectively (68 per cent confidence level), corrected for initialization error. We use a scheme based on radiofrequency magnetic field gradients combined with microwave magnetic fields that is robust against multiple sources of decoherence and usable with essentially any trapped ion species. The scheme has the potential to perform simultaneous entangling operations on multiple pairs of ions in a large-scale trapped-ion quantum processor without increasing control signal power or complexity. Combining this technology with low-power laser light delivered via trap-integrated photonics21,22 and trap-integrated photon detectors for qubit readout23,24 provides an opportunity for scalable, high-fidelity, fully chip-integrated trapped-ion quantum computing.
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A range of abnormalities may acutely affect the upper limb (UL) extremity vasculature including trauma, peripheral vascular disease, and inflammatory conditions. Significant technical advances in computed tomography angiography (CTA) have led to the widespread adoption of this noninvasive modality for rapid evaluation of UL arterial abnormalities in the emergency department setting. A key advantage of CTA over traditional digital subtraction angiography (DSA) is the ability to evaluate concurrent osseous and soft tissue injuries. Accurate identification of pathology requires knowledge of normal UL arterial anatomy in addition to a high-quality study, which may be achieved with a robust CTA protocol. We describe the spectrum of imaging findings on upper limb CTA associated with various acute presentations. Traumatic vascular injuries may occur secondary to penetrating and blunt aetiologies appearing on CTA as contrast extravasation, pooling, pseudoaneurysm, occlusion, and arteriovenous fistula. Peripheral vascular disease manifests as atherosclerotic plaques with thready downstream opacification, and these may precipitate acute thromboembolic events. Inflammatory conditions affecting the UL vasculature includes large and small vessel vasculitides characterised by arterial mural thickening. The use of modalities, including ultrasound and magnetic resonance angiography (MRA), should be considered for further characterisation where appropriate.
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Angiografía por Tomografía Computarizada , Servicio de Urgencia en Hospital , Extremidad Superior , Humanos , Angiografía por Tomografía Computarizada/métodos , Extremidad Superior/irrigación sanguínea , Extremidad Superior/diagnóstico por imagenRESUMEN
BACKGROUND: Blepharoptosis may result in an unattractive appearance and vision problems. According to the severity of ptosis, patients may undergo correction surgery using upper eyelid retractors. The conventional incision for surgical procedures was the double-eyelid incision, potentially resulting in an obvious and unnatural scar or long-lasting edema and prolonged recovery time. OBJECTIVES: The aim of this study was to introduce a supraciliary incision as an alternative to the double-eyelid incision for blepharoptosis correction that creates a scarless, natural appearance with a quick recovery time. METHODS: From June 2019 to June 2021, 32 patients (36 eyelids) underwent blepharoptosis correction through a supraciliary incision. MRD1, the height of the eyelid fissure, and the patient's satisfaction with the shape and scar as well as postoperative complications (eyelid insufficiency, conjunctival prolapse, inadequate correction of ptosis, and excessive correction of ptosis). RESULTS: All 32 patients (36 eyelids) were followed up for 6 to 18 months, with an average follow-up of 11.6 months. The postoperative satisfaction rate was 96.43%. There was no overcorrection, but one patient (1 eyelid, 2.8%) was under correction that required secondary correction. One patient (1 eyelid, 2.8%) experienced conjunctival prolapse. Sixteen patients showed lagophthalmos early after surgery, in which one patient experienced early-stage keratitis and completely recovered within two months. CONCLUSION: Blepharoptosis correction via supraciliary incision allows for broader indications and fewer surgical scars without disrupting eyelid integrity, resulting in quick recovery after surgery. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
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Blefaroplastia , Blefaroptosis , Humanos , Pueblo Asiatico , Blefaroplastia/métodos , Blefaroptosis/cirugía , Cicatriz/cirugía , Estudios de Cohortes , Estética , Satisfacción del Paciente , Estudios Retrospectivos , Resultado del Tratamiento , Complicaciones PosoperatoriasRESUMEN
The phenomenon of world aging is not foreign to indigenous communities. In the last few years, research about these communities around the world has increased, but aging in indigenous towns still has not been studied widely. The purpose of this research is to interpret the meaning of old age in two indigenous communities from the Colombian Andean-Amazon region (the Inga and Kamëntsa) to reinforce the relevance of the local sociocultural context within the configuration of the meaning of old age and to emphasize the importance of considering particular regional characteristics for the design of policies and interventions aiming to recognize and integrate indigenous populations. This is a qualitative study with an interactionism-symbolism approach. In total, six indigenous people older than 60 years from two ancestral communities from the Colombian Andean-Amazon region participated in the in-depth interviews. Data analysis was carried out in three moments: discovery, coding, and relativization of the information. The results show that old age means wisdom, "I am wise," which is supported in the cosmology and the trajectory of life, reinforces the identity and autonomy, and allows them to be agents in the dynamics of their communities from the "I do," in other words, their roles as builders of the family-society and as guards of ancestral knowledge. The loss of this knowledge and the elements that it is composed of uproot them and put them at risk of disappearing as individuals and as a collective. In conclusion, the meaning of old age in these communities is not centered on a determinate age; you are not old, you are wise, and as such, they play a central role in their communities. Moreover, wisdom is built in parallel with their cosmology and assigns them the task of safekeeping ancestral knowledge. In order to do this, they use oral tradition as a tool, words that are born in their territories, travel in a nonlinear timeline, and get strengthened by the community while also protecting it and building it. Knowing what aging means for Indigenous communities can facilitate to the development of policies and initiatives and to provide culturally appropriate and effective programs.
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Envejecimiento , Indígenas Sudamericanos , Pueblos Indígenas , Investigación Cualitativa , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Envejecimiento/etnología , Colombia/etnología , Entrevistas como AsuntoRESUMEN
The unique diffraction geometry of ESRF beamline ID06-LVP offers continuous static 2D or azimuthally resolving data collections over all accessible solid angles available to the tooling geometry. The system is built around a rotating custom-built Pilatus3 CdTe 900k-W detector from Dectris, in a configuration equivalent to three butted 300k devices. As a non-standard geometry, here the method of alignment, correction and subsequent integration for any data collected over all solid angles accessible, or over any azimuthal range contained therein, are provided and illustrated by parameterizing and extending existing pyFAI routines. At 1° integrated intervals, and typical distances (2.0â m), the system covers an area of near 2.5â m2 (100â Mpx square equivalent), to 0.65â Å resolution, at 53â keV from a total dataset of some 312â Mpx. Standard FWHMs of SRM660a LaB6 vary from 0.005° to 0.01°, depending on beam size, energy and sample dimensions, and are sampled at an elevated rate. The azimuthal range per static frame ranges from <20° to â¼1° over the full range of the detector surface. A full 2θ-intensity data collection at static azimuth takes 1-3â s typically, and can be reduced to ms-1 rates for measurements requiring time-rate determination. A full solid-angle collection can be completed in a minute. Sample detector distances are accessible from 1.6â m to 4.0â m.
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BACKGROUND: The extracellular matrix (ECM) is a complex tridimensional scaffold that actively participates in physiological and pathological events. The objective of this study was to test whether structural proteins of the ECM and glycosaminoglycans (GAGs) may favor the retention of human apolipoprotein A-I (apoA-I) variants associated with amyloidosis and atherosclerosis. METHODS: Biopolymeric matrices containing collagen type I (Col, a main macromolecular component of the ECM) with or without heparin (Hep, a model of GAGs) were constructed and characterized, and used to compare the binding of apoA-I having the native sequence (Wt) or Arg173Pro, a natural variant inducing cardiac amyloidosis. Protein binding was observed by fluorescence microscopy and unbound proteins quantified by a colorimetric assay. RESULTS: Both, Wt and Arg173Pro bound to the scaffolds containing Col, but the presence of Hep diminished the binding efficiency. Col-Hep matrices retained Arg173Pro more than the Wt. The retained protein was only partially removed from the matrices with saline solutions, indicating that electrostatic interactions may occur but are not the main driving force. Using in addition thermodynamic molecular simulations and size exclusion chromatography approaches, we suggest that the binding of apoA-I variants to the biopolymeric matrices is driven by many low affinity interactions. CONCLUSIONS: Under this scenario Col-Hep scaffolds contribute to the binding of Arg173Pro, as a cooperative platform which could modify the native protein conformation affecting protein folding. GENERAL SIGNIFICANCE: We show that the composition of the ECM is key to the protein retention, and well characterized biosynthetic matrices offer an invaluable in vitro model to mimic the hallmark of pathologies with interstitial infiltration such as cardiac amyloidosis.
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Amiloidosis , Heparina , Humanos , Amiloidosis/metabolismo , Apolipoproteína A-I/genética , Apolipoproteína A-I/química , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Heparina/metabolismoRESUMEN
BACKGROUND: To support interventions to prevent mother-to-child transmission of hepatitis B and fill gaps in surveillance, the Enhanced Surveillance of Antenatal Hepatitis B (ESAHB) programme was implemented in London from 2008 to 2018 to collect demographic information on women who tested positive for hepatitis B during antenatal screening. We describe the epidemiology of hepatitis B in pregnancy, as reported to ESAHB. METHODS: The characteristics of pregnant women living with hepatitis B were described and rates were calculated by year, local authority and residence deprivation decile (1 being most deprived). Poisson regression tested the association between pregnant women living with hepatitis B and deprivation decile. RESULTS: Between 2008 and 2018, 8879 women living with hepatitis B in London (0.35 per 1000 women) reported 11 193 pregnancies. Annual hepatitis B rates remained stable, but there was strong evidence for an inverse association between rate and deprivation decile (P < 0.001). The majority of women in the cohort presented late to antenatal care, were born outside the UK in a hepatitis B endemic area or required an interpreter for consultations. CONCLUSIONS: ESAHB provided important data to inform service quality improvements for women living with hepatitis B. This analysis highlights the link between deprivation and hepatitis B.
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Hepatitis B , Complicaciones Infecciosas del Embarazo , Femenino , Embarazo , Humanos , Atención Prenatal , Complicaciones Infecciosas del Embarazo/diagnóstico , Complicaciones Infecciosas del Embarazo/epidemiología , Londres/epidemiología , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Hepatitis B/epidemiologíaRESUMEN
BACKGROUND: Socioeconomically disadvantaged children are disproportionately affected by oral disease. Mobile dental services help underserved communities overcome barriers to accessing health care, including time, geography, and trust. The NSW Health Primary School Mobile Dental Program (PSMDP) is designed to provide diagnostic and preventive dental services to children at their schools. The PSMDP is mainly targeted toward high-risk children and priority populations. This study aims to evaluate the program's performance across five local health districts (LHDs) where the program is being implemented. METHODS: The evaluation will use routinely collected administrative data, along with other program-specific data sources, from the district public oral health services to conduct a statistical analysis that determines the reach and uptake of the program, its effectiveness, and the associated costs and cost-consequences. The PSMDP evaluation program utilises data from Electronic Dental Records (EDRs) and other data sources, including patient demographics, service mix, general health, oral health clinical data and risk factor information. The overall design includes cross-sectional and longitudinal components. The design combines comprehensive output monitoring across the five participating LHDs and investigates the associations between socio-demographic factors, service patterns and health outcomes. Time series analysis using difference-in-difference estimation will be conducted across the four years of the program, involving services, risk factors, and health outcomes. Comparison groups will be identified via propensity matching across the five participating LHDs. An economic analysis will estimate the costs and cost-consequences for children who participate in the program versus the comparison group. DISCUSSION: The use of EDRs for oral health services evaluation research is a relatively new approach, and the evaluation works within the limitations and strengths of utilising administrative datasets. The study will also provide avenues to improve the quality of data collected and system-level improvements to better enable future services to be aligned with disease prevalence and population needs.
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Salud Bucal , Instituciones Académicas , Niño , Humanos , Nueva Gales del Sur , Estudios Transversales , Gobierno Estatal , AustraliaRESUMEN
OBJECTIVE: The aim of this study was to elucidate the vital role of anterior-only osteotomies for rigid cervical kyphosis causing stretch myelopathy by using illustrative cases and high-definition intraoperative videos. METHODS: The authors describe 4 select patients who underwent anterior-only osteotomies within a 2-year time frame and demonstrate the nuances of each case with unique operative videos. RESULTS: Outcomes for each of the cases demonstrated marked improvement in cervical spine alignment relative to preoperative conditions. Postoperative CT scans and upright radiographs for case 1 at 8 months demonstrated complete reduction of the kyphotic deformity and restoration of the C2 slope. In case 2, the 2-year postoperative radiographs showed significant realignment of the cervical spine, and the patient made significant neurological improvement since the operation, specifically in hand dexterity, balance, neck pain, and the ability to comfortably achieve and maintain a horizontal gaze. For case 3, postoperative upright radiographs revealed marked improvement in the patient's cervical sagittal alignment. The 4-month follow-up was also notable for substantial improvement in postural neck pain, bilateral upper extremity strength, and continued improvements in dexterity. Case 4 also demonstrated an excellent outcome with unkinking of the patient's spinal cord and correction of her sagittal plane deformity, as shown on her 5-month postoperative upright radiographs. CONCLUSIONS: Deformity-associated cervical spondylotic stretch myelopathy often leads to devastating neurological decline and can significantly decrease quality of life. Carefully selected cases of circumferentially rigid cervical kyphosis can be successfully corrected with anterior-only osteotomies followed by posterior fixation while avoiding back-front-back operations.
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Cifosis , Enfermedades de la Médula Espinal , Humanos , Femenino , Dolor de Cuello , Calidad de Vida , Enfermedades de la Médula Espinal/complicaciones , Enfermedades de la Médula Espinal/diagnóstico por imagen , Enfermedades de la Médula Espinal/cirugía , Vértebras Cervicales/diagnóstico por imagen , Vértebras Cervicales/cirugía , Cifosis/diagnóstico por imagen , Cifosis/etiología , Cifosis/cirugíaRESUMEN
OBJECTIVES: This study aimed to (1) provide a comprehensive overview of contraceptive methods self-reported by men in England, over 5 years, focusing on condoms in comparison to any male method; and (2) explore condom as a contraceptive method by region and ethnicity. STUDY DESIGN: Data were from the Sexual and Reproductive Health Services (Contraception) England census data set from 2014/15 to 2018/19. Once missing data were removed, this left a total of 365,292 men. Two binomial logistic regression models were performed. Model 1 examined ethnicity, region, and time on condom as a method of contraception; and Model 2 examined ethnicity, region, and time by any male contraceptive. Descriptive statistics were run for natural family planning and spermicide. RESULTS: Model 1 revealed a significant model, χ2 (15) = 30,976, P < 0.001, and predicted that condoms as a method decreased in London with a greater decrease in Midlands. London saw the lowest rate of decline among the non-White ethnic group, whereas North and South regions increased probability over time. The North started at a higher probability and the South at the lowest. Model 2 also revealed a significant model, χ2 (15) = 32,472, P < 0.001, with a similar pattern to Model 1. Contingency tables showed natural family planning and spermicide were the least reported methods and decreased over time. CONCLUSIONS: As any male contraceptive method appears to be decreasing in both models, reproductive health promotion is required. This study has implications for commissioning funds and for identifying regional areas of further investigation.
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Condones , Espermicidas , Femenino , Masculino , Humanos , Anticonceptivos , Métodos Naturales de Planificación Familiar , Anticoncepción/métodosRESUMEN
OBJECTIVES: The aim of this study was to describe the epidemiology of COVID-19 cases at universities in England (October 2020-February 2022) and investigate factors associated with rates of COVID-19 among students during autumn/winter of 2021/22. STUDY DESIGN: The study was an observational retrospective study using routine contact tracing data. METHODS: Estimates of COVID-19 cases among students and staff at universities were described. Student cases aged 18-24 years were calculated as a percentage of all cases within that age group. Count regression was used to explore university characteristics associated with case numbers. RESULTS: We identified 102,382 cases among students and 28,639 among staff. Student cases reflected trends in the wider population of the same age group, but the observed fraction aged 18-24 years who were students was consistently below the expected level (32%). Phased reopening of universities in March-May 2021 was associated with small peaks but low absolute numbers. Russell group membership, campus universities, and higher student proportions in halls of residence were all associated with increased case numbers. CONCLUSIONS: COVID-19 case numbers among students in England varied considerably. At no time were the observed case numbers as high as expected from community prevalence. Characteristics of universities associated with higher case rates can inform future guidance for higher education settings.
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OBJECTIVE: Most respiratory virus surveillance relies on medically attended respiratory illness, but an understanding of the true patterns of infection independent of care-seeking behaviour would enhance clinical and public health responses to respiratory virus outbreaks. We evaluated the potential of decedent surveillance by estimating the burden of respiratory virus infection in decedents in a large, urban medical examiner's office. STUDY DESIGN: Observational. METHODS: In 2020-2022, we tested nasopharyngeal swabs from 4121 decedents in Detroit, Michigan for 15 respiratory viruses, including SARS-CoV-2, respiratory syncytial virus, and influenza virus A and B. We analysed infection prevalence over time and by age, sex, race/ethnicity, and manner of death. RESULTS: Of 4113 valid tests, 30.2% were positive for at least one virus, and 6.1% were positive for multiple viruses. All viruses were detected except for influenza A/H1N1 and influenza B. The most prevalent viruses were SARS-CoV-2 (15.7%), rhinovirus (11.2%), and adenovirus (4.9%), which were detected in all months. Most viruses exhibited decreasing prevalence with age, higher prevalence among Black and Hispanic than among White decedents and lower prevalence among deaths from natural causes; SARS-CoV-2 was a notable exception to the patterns by age and manner of death, instead reflecting community trends in catchment counties. CONCLUSIONS: There was high prevalence and diversity of respiratory viruses in decedents entering a large, urban medical examiner's office. Decedent surveillance could offer a clearer picture of the true underlying burden of infection, motivating public health priorities for intervention and vaccine development, and augmenting data for real-time response to respiratory virus outbreaks.
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OBJECTIVES: Integrated disease surveillance (IDS) offers the potential for better use of surveillance data to guide responses to public health threats. However, the extent of IDS implementation worldwide is unknown. This study sought to understand how IDS is operationalized, identify implementation challenges and barriers, and identify opportunities for development. STUDY DESIGN: Synthesis of qualitative studies undertaken in seven countries. METHODS: Thirty-four focus group discussions and 48 key informant interviews were undertaken in Pakistan, Mozambique, Malawi, Uganda, Sweden, Canada, and England, with data collection led by the respective national public health institutes. Data were thematically analysed using a conceptual framework that covered governance, system and structure, core functions, finance and resourcing requirements. Emerging themes were then synthesised across countries for comparisons. RESULTS: None of the countries studied had fully integrated surveillance systems. Surveillance was often fragmented, and the conceptualization of integration varied. Barriers and facilitators identified included: 1) the need for clarity of purpose to guide integration activities; 2) challenges arising from unclear or shared ownership; 3) incompatibility of existing IT systems and surveillance infrastructure; 4) workforce and skills requirements; 5) legal environment to facilitate data sharing between agencies; and 6) resourcing to drive integration. In countries dependent on external funding, the focus on single diseases limited integration and created parallel systems. CONCLUSIONS: A plurality of surveillance systems exists globally with varying levels of maturity. While development of an international framework and standards are urgently needed to guide integration efforts, these must be tailored to country contexts and guided by their overarching purpose.
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Salud Pública , Humanos , Grupos Focales , Investigación Cualitativa , Uganda/epidemiología , Recolección de DatosRESUMEN
Paper-based electrochemical analytical devices (ePADs) have gained significant interest as promising analytical units in recent years because they can be fabricated in simple ways, are low-cost, portable, and disposable platforms that can be applied in various fields. In this sense, paper-based electrochemical biosensors are attractive analytical devices since they can promote diagnose several diseases and potentially allow decentralized analysis. Electrochemical biosensors are versatile, as the measured signal can be improved by using mainly molecular technologies and nanomaterials to attach biomolecules, resulting in an increase in their sensitivity and selectivity. Additionally, they can be implemented in microfluidic devices that drive and control the flow without external pumping and store reagents, and improve the mass transport of analytes, increasing sensor sensitivity. In this review, we focus on the recent developments in electrochemical paper-based devices for viruses' detection, including COVID-19, Dengue, Zika, Hepatitis, Ebola, AIDS, and Influenza, among others, which have caused impacts on people's health, especially in places with scarce resources. Also, we discuss the advantages and disadvantages of the main electrode's fabrication methods, device designs, and biomolecule immobilization strategies. Finally, the perspectives and challenges that need to be overcome to further advance paper-based electrochemical biosensors' applications are critically presented.
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Técnicas Biosensibles , COVID-19 , Nanoestructuras , Infección por el Virus Zika , Virus Zika , Humanos , COVID-19/diagnóstico , Nanoestructuras/química , Técnicas Biosensibles/métodos , Dispositivos Laboratorio en un Chip , Prueba de COVID-19RESUMEN
Dermoid cysts are slowly growing benign lesions of ectodermal tissue that often occur in the anterior fontanelle. Clinicians often rely on a negative transillumination test to begin the process of correctly diagnosing a dermoid cyst. However, here the authors present a case of a 7-month-old girl who presents with a transilluminating dermoid cyst.
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Fontanelas Craneales , Quiste Dermoide , Neoplasias Craneales , Transiluminación , Fontanelas Craneales/diagnóstico por imagen , Fontanelas Craneales/patología , Fontanelas Craneales/cirugía , Quiste Dermoide/diagnóstico por imagen , Quiste Dermoide/cirugía , Humanos , Femenino , Niño , Neoplasias Craneales/diagnóstico por imagen , Neoplasias Craneales/cirugía , Imagen por Resonancia Magnética , Resultado del TratamientoRESUMEN
Detecting microevolutionary responses to natural selection by observing temporal changes in individual breeding values is challenging. The collection of suitable datasets can take many years and disentangling the contributions of the environment and genetics to phenotypic change is not trivial. Furthermore, pedigree-based methods of obtaining individual breeding values have known biases. Here, we apply a genomic prediction approach to estimate breeding values of adult weight in a 35-year dataset of Soay sheep (Ovis aries). Comparisons are made with a traditional pedigree-based approach. During the study period, adult body weight decreased, but the underlying genetic component of body weight increased, at a rate that is unlikely to be attributable to genetic drift. Thus cryptic microevolution of greater adult body weight has probably occurred. Genomic and pedigree-based approaches gave largely consistent results. Thus, using genomic prediction to study microevolution in wild populations can remove the requirement for pedigree data, potentially opening up new study systems for similar research.
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Genoma , Genómica , Animales , Peso Corporal , Genotipo , Modelos Genéticos , Linaje , Fenotipo , OvinosRESUMEN
Key sources of information on the nature of early terrestrial ecosystems are the fossilized remains of plants and associated organic encrustations, which are interpreted as either biofilms, biological soil crusts or lichens. The hypothesis that some of these encrustations might be the remains of the thalloid gametophytes of embryophytes provided the stimulus for this investigation. Fossils preserved in charcoal were extracted from Devonian Period (Lochkovian Stage, c. 410-419 Myr old) sediments at a geological site in Shropshire (UK). Scanning electron micrographs (SEMs) of the fossils were compared with new and published SEMs of extant bryophytes and tracheophytes, respectively. One specimen was further prepared and imaged by transmission electron microscopy. Fossils of thalloid morphology were composed almost entirely of cells with labyrinthine ingrowths; these also were present in fossils of axial morphology where they were associated with putative food-conducting cells. Comparison with modern embryophytes demonstrates that these distinctive cells are transfer cells (TCs). Our fossils provide by far the earliest geological evidence of TCs. They also show that some organic encrustations are the remains of thalloid land plants and that these are possibly part of the life cycle of a newly recognized group of plants called the eophytes.
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Evolución Biológica , Embryophyta , Ecosistema , Fósiles , PlantasRESUMEN
Chemical reactions and phase stabilities in the Si-Te system at high pressures were explored using in situ angle-dispersive synchrotron powder diffraction in a large-volume multianvil press together with density functional theory-based calculations. Cubic and rhombohedrally distorted clathrates, with the general formula Te8@(Si38Te8) and wide compositional range, preceded by a hexagonal phase with the composition Si0.14Te, are formed for different mixtures of Si and Te as starting materials. Si0.14Te, with the structural formula Te2(Te0.74Si0.26)3(Te0.94Si0.06)3, is the very first chalcogenide with the Mn5Si3-type structure. Silicon sesquitelluride α-Si2Te3 decomposes into a mixture of phases that includes the clathrate and hexagonal phases at high pressures and high temperatures. The higher the pressure, the lower the temperature for the two phases to occur. Regardless of the starting compositions, only the clathrate is quenched to atmospheric conditions, while the hexagonal phase amorphizes on decompression. The rhombohedral clathrates Te8@(Si38Te8) form on quenching of the cubic phases to ambient conditions. There is a high degree of interchangeability of Si and Te not only in the clathrates but also in the Mn5Si3-type structure. The theoretical calculations of enthalpies indicate that the reported decomposition of α-Si2Te3 is energetically favorable over its transformation to another polymorph of the A2X3 type at extreme conditions.
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BACKGROUND: Pharmacological pain management options can relieve women's pain during labour and birth. Trials of these interventions have used a wide variety of outcomes, complicating meaningful comparisons of their effects. To facilitate better assessment of the effectiveness of labour pain management in trials and meta-analyses, consensus about key outcomes and the development of a core outcome set is essential. OBJECTIVE: To identify all outcomes used in studies of pharmacological pain management interventions during labour and birth. DESIGN: A review of systematic reviews and their included randomised controlled trials was undertaken. SEARCH STRATEGY: Cochrane CENTRAL was searched to identify all Cochrane systematic reviews describing pharmacological pain management options for labour and birth. Search terms included 'pain management', 'labour' and variants, with no limits on year of publication or language. SELECTION CRITERIA: Cochrane reviews and randomised controlled trials contained within these reviews were included, provided they compared a pharmacological intervention with other pain management options, placebo or no treatment. DATA COLLECTION AND ANALYSIS: All outcomes reported by reviews or trials were extracted and tabulated, with frequencies of individual outcomes reported. MAIN RESULTS: Nine Cochrane reviews and 227 unique trials were included. In total, 146 unique outcomes were identified and categorised into maternal, fetal, neonatal, child, health service, provider's perspective or economic outcome domains. CONCLUSIONS: Outcomes of pharmacological pain management interventions during labour and birth vary widely between trials. The standardisation of trial outcomes would permit the assessment of meta-analyses for best clinical practice. TWEETABLE ABSTRACT: Outcomes to measure pharmacological pain management options during labour are highly variable and require standardisation.
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Dolor de Parto , Trabajo de Parto , Femenino , Humanos , Recién Nacido , Dolor de Parto/tratamiento farmacológico , Manejo del Dolor , Parto , Embarazo , Ensayos Clínicos Controlados Aleatorios como Asunto , Revisiones Sistemáticas como AsuntoRESUMEN
Microvascular imaging (MVI) is an advanced Doppler ultrasound technique, permitting detailed evaluation of microvessel architecture without the need for contrast agents. The clinical applications of the technology are broad, with a growing body of evidence suggesting a potential role for MVI in the characterisation of benign and malignant focal liver lesions (FLLs). This review discusses the current evidence regarding the use of MVI in the assessment of FLLs, with a proposed algorithmic approach to radiological work-up of FLLs based on MVI features. Ongoing research and future directions in the field are highlighted.