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1.
J Synchrotron Radiat ; 31(Pt 3): 432-437, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38587895

RESUMO

At-wavelength metrology of X-ray optics plays a crucial role in evaluating the performance of optics under actual beamline operating conditions, enabling in situ diagnostics and optimization. Techniques utilizing a wavefront random modulator have gained increasing attention in recent years. However, accurately mapping the measured wavefront slope to a curved X-ray mirror surface when the modulator is downstream of the mirror has posed a challenge. To address this problem, an iterative method has been developed in this study. The results demonstrate a significant improvement compared with conventional approaches and agree with offline measurements obtained from optical metrology. We believe that the proposed method enhances the accuracy of at-wavelength metrology techniques, and empowers them to play a greater role in beamline operation and optics fabrication.

2.
J Synchrotron Radiat ; 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39078691

RESUMO

In situ wavefront sensing plays a critical role in the delivery of high-quality beams for X-ray experiments. X-ray speckle-based techniques stand out among other in situ techniques for their easy experimental setup and various data acquisition modes. Although X-ray speckle-based techniques have been under development for more than a decade, there are still no user-friendly software packages for new researchers to begin with. Here, we present an open-source Python package, spexwavepy, for X-ray wavefront sensing using speckle-based techniques. This Python package covers a variety of X-ray speckle-based techniques, provides plenty of examples with real experimental data and offers detailed online documentation for users. We hope it can help new researchers learn and apply the speckle-based techniques for X-ray wavefront sensing to synchrotron radiation and X-ray free-electron laser beamlines.

3.
J Synchrotron Radiat ; 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39120915

RESUMO

A state-of-the-art multilayer deposition system with a 4200 mm-long linear substrate translator housed within an ultra-high vacuum chamber has been developed. This instrument is engineered to produce single and multilayer coatings, accommodating mirrors up to 2000 mm in length through the utilization of eight rectangular cathodes. To ensure the quality and reliability of the coatings, the system incorporates various diagnostic tools for in situ thickness uniformity and stress measurement. Furthermore, the system features an annealing process capable of heating up to 700°C within the load-lock chamber. The entire operation, including pump down, deposition and venting processes, is automated through user-friendly software. In addition, all essential log data, power of sputtering source, working pressure and motion positions are automatically stored for comprehensive data analysis. Preliminary commissioning results demonstrate excellent lateral film thickness uniformity, achieving 0.26% along the translation direction over 1500 mm in dynamic mode. The multilayer deposition system is poised for use in fabricating periodic, lateral-graded and depth-graded multilayers, specifically catering to the beamlines for diverse scientific applications at Diamond Light Source.

4.
J Synchrotron Radiat ; 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39088402

RESUMO

Multilayer gratings are increasingly popular optical elements at X-ray beamlines, as they can provide much higher photon flux in the tender X-ray range compared with traditional single-layer coated gratings. While there are several proprietary software tools that provide the functionality to simulate the efficiencies of such gratings, until now the X-ray community has lacked an open-source alternative. Here MLgrating is presented, a program for simulating the efficiencies of both multilayer gratings and single-layer coated gratings for X-ray applications. MLgrating is benchmarked by comparing its output with that of other software tools and plans are discussed for how the program could be extended in the future.

5.
J Synchrotron Radiat ; 31(Pt 4): 655-669, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38771776

RESUMO

Synchrotron light sources require X-ray optics with extremely demanding accuracy for the surface profile, with less than 100 nrad slope errors and sub-nanometre height errors. Such errors are challenging to achieve for aspheres using traditional polishing methods. However, post-polishing error correction can be performed using techniques such as ion beam figuring (IBF) to improve optics to the desired quality. This work presents a brief overview of the history of IBF, introduces some of the challenges for obtaining such demanding figure errors, and highlights the work done at several in-house IBF facilities at synchrotron light sources worldwide to obtain state-of-the-art optical quality.

6.
J Synchrotron Radiat ; 31(Pt 4): 706-715, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38904938

RESUMO

Ion beam figuring (IBF) is a powerful technique for figure correction of X-ray mirrors to a high accuracy. Here, recent technical advancements in the IBF instrument developed at Diamond Light Source are presented and experimental results for figuring of X-ray mirrors are given. The IBF system is equipped with a stable DC gridded ion source (120 mm diameter), a four-axis motion stage to manipulate the optic, a Faraday cup to monitor the ion-beam current, and a camera for alignment. A novel laser speckle angular measurement instrument also provides on-board metrology. To demonstrate the IBF system's capabilities, two silicon X-ray mirrors were processed. For 1D correction, a height error of 0.08 nm r.m.s. and a slope error of 44 nrad r.m.s. were achieved. For 2D correction over a 67 mm × 17 mm clear aperture, a height error of 0.8 nm r.m.s. and a slope error of 230 nrad r.m.s. were obtained. For the 1D case, this optical quality is comparable with the highest-grade, commercially available, X-ray optics.

7.
Med Sci Monit ; 30: e943126, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38704632

RESUMO

BACKGROUND Severe anemia caused by hemorrhoidal hematochezia is typically treated preoperatively with reference to severe anemia treatment strategies from other etiologies. This retrospective cohort study included 128 patients with hemorrhoidal severe anemia admitted to 3 hospitals from September 1, 2018, to August 1, 2023, and aimed to evaluate preoperative blood transfusion requirements. MATERIAL AND METHODS Of 5120 patients with hemorrhoids, 128 (2.25%; male/female: 72/56) experienced hemorrhoidal severe anemia, transfusion, and Milligan-Morgan surgery. Patients were categorized into 2 groups based on their preoperative hemoglobin (PHB) levels after transfusion: PHB ≥70 g/L as the liberal-transfusion group (LG), and PHB <70 as the restrictive-threshold group (RG). The general condition, bleeding duration, hemoglobin level on admission, transfusion volume, length of stay, immune transfusion reaction, surgical duration, and hospitalization cost were compared between the 2 groups. RESULTS Patients with severe anemia (age: 41.07±14.76) tended to be younger than those with common hemorrhoids (age: 49.431±15.59 years). The LG had a significantly higher transfusion volume (4.77±2.22 units), frequency of immune transfusion reactions (1.22±0.58), and hospitalization costs (16.69±3.31 thousand yuan) than the RG, which had a transfusion volume of 3.77±2.09 units, frequency of immune transfusion reactions of 0.44±0.51, and hospitalization costs of 15.00±3.06 thousand yuan. Surgical duration in the LG (25.69±14.71 min) was significantly lower than that of the RG (35.24±18.72 min). CONCLUSIONS Patients with hemorrhoids with severe anemia might require a lower preoperative transfusion threshold than the currently recognized threshold, with an undifferentiated treatment effect and additional benefits.


Assuntos
Anemia , Transfusão de Sangue , Hemorroidas , Cuidados Pré-Operatórios , Humanos , Masculino , Feminino , Estudos Retrospectivos , Anemia/terapia , Anemia/etiologia , Transfusão de Sangue/métodos , Pessoa de Meia-Idade , Adulto , Hemorroidas/cirurgia , Hemorroidas/complicações , Cuidados Pré-Operatórios/métodos , Hemoglobinas/análise , Hemoglobinas/metabolismo , Tempo de Internação , Hemorragia Gastrointestinal/cirurgia , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/terapia , Idoso
8.
Aging (Albany NY) ; 16(10): 8822-8842, 2024 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-38771142

RESUMO

The role of inflammation is increasingly understood to have a central influence on therapeutic outcomes and prognosis in lung adenocarcinoma (LUAD). However, the detailed molecular divisions involved in inflammatory responses are yet to be fully elucidated. Our study identified two main inflammation-oriented LUAD grades: the inflammation-low (INF-low) and the inflammation-high (INF-high) subtypes. Both presented with unique clinicopathological features, implications for prognosis, and distinctive tumor microenvironment profiles. Broadly, the INF-low grade, marked by its dominant immunosuppressive tumor microenvironment, was accompanied by less favorable prognostic outcomes and a heightened prevalence of oncogenic mutations. In contrast, the INF-high grade exhibited more optimistic clinical trajectories, underscored by its immune-active environment. In addition, our efforts led to the conceptualization and empirical validation of an inflammation-centric predictive model with considerable predictive potency. Our study paves the way for a refined inflammation-centric LUAD classification and fosters a deeper understanding of tumor microenvironment intricacies.


Assuntos
Adenocarcinoma de Pulmão , Inflamação , Neoplasias Pulmonares , Microambiente Tumoral , Humanos , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/imunologia , Adenocarcinoma de Pulmão/patologia , Inflamação/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/imunologia , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia , Feminino , Masculino , RNA-Seq , Pessoa de Meia-Idade , Prognóstico , Análise de Célula Única , Idoso , Regulação Neoplásica da Expressão Gênica , Análise da Expressão Gênica de Célula Única
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