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OBJECTIVE: To determine whether we can safely and successfully transplant an ovary tissue allograft from a non-identical donor to her Turner syndrome sister. DESIGN: Transplantation of cryopreserved ovary tissue, as well as fresh transplantation of ovarian tissue between identical twins, is now well established with numerous reported successful cases. However there have not yet been any ovary transplants between non-identical women requiring immunosuppression (ovary allotransplant). This could be a much more common indication for ovary tissue transplantation if safe and reliable immunosuppression were available. SUBJECTS: A 20 year old amenorrheic woman with non-mosaic 45-XO Turner syndrome requested ovary tissue transplantation from her fertile 22 year old 46-XX sister. They were an HLA match but were ABO incompatible, a well known contra-indication to solid tissue or organ transplantation. The Turner syndrome sister strongly preferred to be able to become pregnant naturally without donor egg IVF, and to avoid HRT (hormone replacement therapy). In her religious group, that would also be important for finding a marital match. Despite the poor prognosis associated with ABO incompatibility, an ovary from her 22 year old non-identical fertile sister was transplanted to her employing the immunosuppression protocol now used for kidney transplant patients in our centers at Washington University and Johns Hopkins. MAIN OUTCOME MEASURES: Post-operatively at 5 months she developed normal monthly menstrual ovarian function, and she became spontaneously pregnant with a normal baby girl. The relation between her post-op FSH and AMH levels continues to support the theory that tissue pressure controls primordial follicle recruitment. The fact that ABO incompatibility did not prevent success suggests that diffusion and not revascularization may be all that is required for successful long term ovarian cortex transplant survival with spontaneous pregnancy. RESULTS: Ovary allotransplantation with safe immunosuppression allows natural conception, and also normal hormone function obviates the need for HRT. Orthotopic placement of the graft and surgical technique is critical for natural conception and a higher pregnancy rate. CONCLUSION: Allotransplantation requiring safe immunosuppression, if successful, may be a much more commonly used indication for ovary transplantation in the future than frozen ovary grafts or grafts between identical twins.
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We demonstrate the transfer of a cesium frequency standard steered to UTC(NIST) over 20 km of dark telecom optical fiber. Our dissemination scheme uses an active stabilization technique with a phase-locked voltage-controlled oscillator. Out-of-loop characterization of the optical fiber link performance is done with dual-fiber and single-fiber transfer schemes. We observe a fractional frequency instability of 1.5 × 10-12 and 2 × 10-15 at averaging intervals of 1 s and 105 s, respectively, for the link. Both schemes are sufficient to transfer the cesium clock reference without degrading the signal, with nearly an order of magnitude lower fractional frequency instability than the cesium clocks over all time scales. The simplicity of the two-fiber technique may be useful in future long-distance applications where higher stability requirements are not paramount, as it avoids technical complications involved with the single-fiber scheme.
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BACKGROUND: Remote delivery of multi-component weight management interventions results in clinically meaningful weight loss in adults without intellectual disabilities (ID), but the effectiveness of remotely delivered weight management interventions in adults with ID has not previously been evaluated. OBJECTIVE: To determine if a weight management intervention delivered remotely could achieve weight loss (kg) at 6 months that is non-inferior to in-person visits in adults with ID and overweight or obesity (BMI ≥25 kg/m2). METHODS: Participants were randomized to a 24-mo. trial (6 mos weight loss,12 mos weight maintenance, 6 mos. no-contact follow up) to compare weight loss achieved with the same multicomponent intervention delivered to individual participants in their home either remotely (RD) or during face-to-face home visits (FTF). RESULTS: One hundred twenty adults with ID (â¼32 years of age, 53 % females) were randomized to the RD (n = 60) or the FTF arm (n = 60). Six-month weight loss in the RD arm (-4.9 ± 7.8 kg) was superior to 6-month weight loss achieved in the FTF arm (-2.1 ± 6.7 kg, p = 0.047). However, this may be partially attributed to the COVID-19 pandemic, since weight loss in the FTF arm was greater in participants who completed the intervention entirely pre-COVID (n = 33,-3.2 %) compared to post-COVID (n = 22, -0.61 %). Weight loss across did not differ significantly between intervention arms at 18 (p = 0.33) or 24 months (p = 0.34). CONCLUSION: Our results suggest that remote delivery is a viable option for achieving clinically relevant weight loss and maintenance in adults with ID. NCT REGISTRATION: NCT03291509.
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Personas con Discapacidad , Discapacidad Intelectual , Adulto , Femenino , Humanos , Persona de Mediana Edad , Masculino , Discapacidad Intelectual/complicaciones , Pandemias , Obesidad/terapia , Obesidad/epidemiología , Pérdida de PesoRESUMEN
This paper will review a remarkable new approach to in vitro maturation "IVM" of oocytes from ovarian tissue, based on our results with in vitro oogenesis from somatic cells. As an aside benefit we also have derived a better understanding of ovarian longevity from ovary transplant. We have found that primordial follicle recruitment is triggered by tissue pressure gradients. Increased pressure holds the follicle in meiotic arrest and prevents recruitment. Therefore recruitment occurs first in the least dense inner tissue of the cortico-medullary junction. Many oocytes can be obtained from human ovarian tissue and mature to metaphase 2 in vitro with no need for ovarian stimulation. Ovarian stimulation may only be necessary for removing the oocyte from the ovary, but this can also be accomplished by simple dissection at the time of ovary tissue cryopreservation. By using surgical dissection of the removed ovary, rather than a needle stick, we can obtain many oocytes from very small follicles not visible with ultrasound. A clearer understanding of ovarian function has come from in vitro oogenesis experiments, and that explains why IVM has now become so simple and robust. Tissue pressure (and just a few "core genes" in the mouse) direct primordial follicle recruitment and development to mature oocyte, and therefore also control ovarian longevity. There are three distinct phases to oocyte development both in vitro and in vivo: in vitro differentiation "IVD" which is not gonadotropin sensitive (the longest phase), in vitro gonadotropin sensitivity "IVG" which is the phase of gonadotropin stimulation to prepare for meiotic competence, and IVM to metaphase II. On any given day 35% of GVs in ovarian tissue have already undergone "IVD" and "IVG" in vivo, and therefore are ready for IVM.
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Técnicas de Maduración In Vitro de los Oocitos , Oogénesis , Ovario , Femenino , Animales , Oogénesis/fisiología , Humanos , Ovario/fisiología , Oocitos/fisiología , Folículo Ovárico/fisiología , RatonesRESUMEN
[This corrects the article DOI: 10.3389/fnagi.2023.1285333.].
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Residual time delays in time transfer systems such as two-way satellite time and frequency transfer (TWSTFT), or GPS carrier phase (GPSCP) change over time. A double difference such as TWSTFT-GPSCP provides information on the changes in the relative time delays of the two systems. These changes are referred to as aging or time dispersion. A first difference statistic, RMS time interval error, TIERMS, provides the RMS time dispersion. The time deviation statistic (TDEV) or a variation on the Allan deviation (ADEV), referred to here as ADEVS, provide information on the nature of the random fluctuations in aging. This paper describes analytical and Monte Carlo techniques used to estimate the aging (time dispersion) from TDEV or ADEVS statistics, and finds that the aging can be more than a factor of four larger than TDEV or ADEVS. The use of ADEVS is recommended over TDEV since it is sensitive to time drift.
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X-ray inspection systems are critical in medical, non-destructive testing, and security applications, with systems typically measuring attenuation along straight-line paths connecting sources and detectors. Computed tomography (CT) systems can provide higher-quality images than single- or dual-view systems, but the need to measure many projections leads to greater system cost and complexity. Typically, off-angle Compton scattered photons are treated as noise during tomographic inversion. We seek to maximize the image quality of limited-view systems by combining attenuation data with measurements of Compton-scattered photons, exploiting the fact that the broken-ray paths followed by scattered photons provide additional geometric sampling of the scene. We describe a single-scatter forward model for Compton-scatter data measured with energy-resolving detectors, and demonstrate a reconstruction algorithm for density that combines both attenuation and scatter measurements. The experimental results suggest that including Compton-scattered data in the reconstruction process can improve image quality for density reconstruction using limited-view systems.
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Los estudiantes que se preparan ahora para desarrollar su carrera en empresas, hallan que el estudio de este libro proporcionará un respaldo de comprensión que será valioso en los puestos a cargo de dirección en todos los niveles. Sin embargo, las funciones de recursos humanos son efectadas también por los gerentes y supervisores de línea. De muchos modos estos funcionarios tienen una mayor oportunidad de contribuir a la organización por la forma en que implementan las políticas y procedimientos relacionados con la administración de los recursos humanos. En todo este libro se examinan en detalle las importantes funciones de gerente y supervisor, así como las de los administradores de recursos humanos
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Administración de PersonalRESUMEN
En este libro más de la mitad del texto se dedica a las ciencias del comportamiento, entérminos tanto teóricos como de aplicación. Así pues, las ciencias de la conducta están consideradas en el contexto del manejo de los recursos humanos en una organización como parte del sistema administrativo total. También se dideca más atención a los procesos básicos de personal implicados en la adquisición, desarrollo y mantenimiento de estos recursos humanos, incluyendo los relativos a la selección, entrenamiento, motivación y remuneración de los empleados y en la conservación de las relaciones con sus sindicatos. Estos procesos se discuten no sólo bajo el punto de vista de la investigación y de la experiencia en el campo administrativo, sino también en términos de lo que se considera ser una práctia efectiva a la luz de teorías contemporáneas de las ciencias del comportamiento
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Administración de PersonalRESUMEN
O maior desafio à psicologia experimental está nas áreas onde o comportamento dos indivíduos é assunto de preocupações (educação, comportamento anormal, treino industrial, etc.). O estudo de organismos individuais requer a eliminação da variabilidade não controlada e o desenvolvimento de linhas bases comportamentais estáveis. As linhas bases comportamentais requerem, por seu turno, que o experimentador construa o repertório de respostas de seu sujeito experimental. Isto é um afastamento dos procedimentos usuais da psicologia experimental. Não há melhor teste para a dequação de uma posição teórica do que a responsabilidade de construir uma linha base comportamental (AU)