Hasil untuk "astro-ph.SR"

Sumit Kumar, A. K. Meshram, A. Astro et al.

Technical advancements and experimental works for the integration of 5G and Non-Terrestrial Networks (NTN) have gained significant traction over the past few years. NTN components have been officially included in the 5G ecosystem by 3GPP in the latest Release-17. 5G-NTN research is ongoing and it is desirable to have a platform that facilitates quick prototyping of the proof-of-concept methods. OpenAirInterface(OAI) is an open-source experimental yet 3GPP standard-compliant Software Defined Radio (SDR) based protocol stack that has been widely known for implementing 4G/5G technologies. Due to its proven capabilities and flexibility, OAI is currently in the developmental process of integrating adaptations for the 5G-NTN. In this work, we discuss the peculiar features of OAI which are shaping it towards becoming a preferred tool for research and experimentation related to 5G-NTN. We provide details of completed/ongoing 5G-NTN projects leveraging OAI to achieve their objectives. In particular, we discuss 5G-GOA and 5G-LEO where critical adaptations in OAI are being done to support 5G-NTN use-cases. Such adaptations enable direct-access between UE and gNB via transparent payload Geostationary (5G-GOA) and Non-geostationary satellites (5G-LEO). Both projects have closely followed 3GPP discussions over 5G-NTN and the adaptations are compliant with the currently frozen 3GPP Release-17. OAI adaptations from both projects will be merged into the main development branch of OAI. We also provide a future roadmap of OAI towards 5G-NTN development. We believe that the pioneering steps taken in the course of the aforementioned projects will establish OAI as a preferred tool for 5G-NTN research and experimentations.

J. Landercasper, D. Attai, D. Atisha et al.

BackgroundMultiple recent reports have documented significant variability of reoperation rates after initial lumpectomy for breast cancer. To address this issue, a multidisciplinary consensus conference was convened during the American Society of Breast Surgeons 2015 annual meeting.MethodsThe conference mission statement was to “reduce the national reoperation rate in patients undergoing breast conserving surgery for cancer, without increasing mastectomy rates or adversely affecting cosmetic outcome, thereby improving value of care.” The goal was to develop a toolbox of recommendations to reduce the variability of reoperation rates and improve cosmetic outcomes. Conference participants included providers from multiple disciplines involved with breast cancer care, as well as a patient representative. Updated systematic reviews of the literature and invited presentations were sent to participants in advance. After topic presentations, voting occurred for choice of tools, level of evidence, and strength of recommendation.ResultsThe following tools were recommended with varied levels of evidence and strength of recommendation: compliance with the SSO-ASTRO Margin Guideline; needle biopsy for diagnosis before surgical excision of breast cancer; full-field digital diagnostic mammography with ultrasound as needed; use of oncoplastic techniques; image-guided lesion localization; specimen imaging for nonpalpable cancers; use of specialized techniques for intraoperative management, including excisional cavity shave biopsies and intraoperative pathology assessment; formal pre- and postoperative planning strategies; and patient-reported outcome measurement.ConclusionsA practical approach to performance improvement was used by the American Society of Breast Surgeons to create a toolbox of options to reduce lumpectomy reoperations and improve cosmetic outcomes.

V. Astro, A. Adamo

The raising worldwide prevalence of Type 1 and Type 2 diabetes mellitus (T1DM and T2DM) solicits the derivation of in vitro methods yielding mature and fully functional β-cells to be used in regenerative medicine. Several protocols to differentiate human embryonic stem cells (hESCs) and induced pluripotent stem cells (iPSCs) into human pancreatic β-like cells have recently been developed. These methods, coupled with a bioengineering approach using biocompatible encapsulating devices, have recently led to experimental clinical trials showing great promises to ultimately end the battle of diabetic patients for managing hyperglycemia. However, in vitro differentiation protocols face the challenge of achieving homogenous population of mono-hormonal insulin-secreting mature β-cells. Major epigenetic events such as DNA methylation, post-translational modification of histones and non-coding RNAs expression, orchestrate physiological endocrine pancreas specification into α-, β-, γ-, and δ-cells, both in vivo and in vitro. The dysregulation of such epigenetic processes is associated to multiple pancreatic disorders including diabetes. Understanding the epigenomic and transcriptomic landscape underlying endocrine pancreas development could, therefore, improve in vitro differentiation methods. In this review, we summarize the most effective protocols for in vitro differentiation of hESCs/hiPSCs toward pancreatic β-cells and we discuss the current limitations in the derivation of functional glucose-responsive, insulin-releasing β-cells. Moreover, we focus on the main transcriptional and epigenetic events leading to pancreatic specification and on the applicative potential of novel epigenetic drugs for the establishment of innovative pharmacological therapeutic approaches.

G. D. Croon, P. K. Gerke, I. Sprinkhuizen-Kuyper

K. Ishimura, K. Minesugi, T. Kawano et al.

Moira K. Christoudias, Abigail E. Collett, T. S. Stull et al.

The American Society for Radiation Oncology (ASTRO) consensus statement (CS) provides guidelines for patient selection for accelerated partial breast irradiation (APBI) following breast conserving surgery. The purpose of this study was to evaluate recurrence rates based on ASTRO CS groupings. A single institution review of 238 early stage breast cancer patients treated with balloon-based APBI via balloon based brachytherapy demonstrated a 4-year actuarial ipsilateral breast tumor recurrence (IBTR) rate of 5.1%. There were no significant differences in the 4-year actuarial IBTR rates between the “suitable,” “cautionary,” and “unsuitable” ASTRO categories (0%, 7.2%, and 4.3%, resp., P = 0.28). ER negative tumors had higher rates of IBTR than ER positive tumors. The ASTRO groupings are poor predictors of patient outcomes. Further studies evaluating individual clinicopathologic features are needed to determine the safety of APBI in higher risk patients.

F. Lascaux, E. Masciadri, L. Fini

This article is the second of a series of articles aiming at proving the feasibility of the forecast of all the most relevant classical atmospherical parameters for astronomical applications (wind speed and direction, temperature, relative humidity) and the optical turbulence (C N and the derived astro-climatic parameters like seeing ε, isoplanatic angle θ0, wavefront coherence time τ0...). This study is done in the framework of the MOSE project, and focused above the two ESO ground-bases sites of Cerro Paranal and Cerro Armazones. In this paper we present the results related to the Meso-Nh model ability in reconstructing the surface layer atmospherical parameters (wind speed intensity, wind direction and absolute temperature, [0-30] m a. g. l.). The model reconstruction of all the atmospherical parameters in the surface layer is very satisfactory. For the temperature, at all levels, the RMSE (Root Mean Square Error) is inferior to 1◦C. For the wind speed, it is ∼2 m·s, and for the wind direction, it is in the range [38-46◦], at all levels, that corresponds to a RMSErelative in a range [21-26%]. If a filter is applied for the wind direction (the winds inferior to 3 m·s are discarded from the computations), the wind direction RMSE is in the range [3041◦], i.e. a RMSErelative in the range [17-23%]. The model operational forecast of the surface layer atmospherical parameters is suitable for different applications, among others: thermalization of the dome using the reconstructed temperature, hours in advance, of the beginning the night; knowing in advance the main direction which the strong winds will come from during the night could allow the astronomer to anticipate the occurrence of a good/bad seeing night, and plan the observations accordingly; preventing adaptive secondary mirrors shake generated by the wind speed.

K. Begeman, A. Belikov, D. Boxhoorn et al.

M. Rioja, R. Dodson, J. Malarecki et al.

J. Steinbeck, E. Ricketts, R. Astro

P. Serlemitsos, Y. Soong, T. Okajima et al.

E. Prather, G. Brissenden

L. Baresi, Sam Guinea, R. Kazhamiakin et al.

W. Blair, K. Long, O. Vancura et al.

A. Witt, J. Petersohn, R. Bohlin et al.

F. Porter, M. D. Audley, P. Beiersdorfer et al.

V. Petegnief, Josep Saura, D. Dewar et al.

M. Şengoz, U. Abacioglu, İ. Çetin et al.

Scott G. Williams, Gillian M. Duchesne, N. Gogna et al.

H. Kamaya, J. Silk

We study the prospects for observing H2 emission during the assembly of primordial molecular cloud kernels. The primordial molecular cloud cores, which resemble those at the present epoch, can emerge around 1þ z , 20 according to recent numerical simulations. The kernels form inside the cores, and the first stars will appear inside the kernels. A kernel typically contracts to form one of the first generation stars with an accretion rate that is as large as ,0.01 M( yr. This occurs owing to the primordial abundances, which result in a kernel temperature of order 1000 K, and the collapsing kernel emits H2 line radiation at a rate ,10 erg s. Predominantly J 1⁄4 5 2 3 ðv 1⁄4 0Þ rotational emission of H2 is expected. At redshift 1þ z , 20, the expected flux is ,0.01mJy for a single kernel. While an individual object is not observable by any facilities available in the near future, the expected assembly of primordial star clusters on subgalactic scales can result in fluxes at the sub-mJy level. This is marginally observable with ASTRO-F and ALMA. We also examine the rotational J 1⁄4 2 2 0 ðv 1⁄4 0Þ and vibrational dv 1⁄4 1 emission lines. The former may possibly be detectable with