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We describe a high-performance molecular iodine optical frequency reference that is referenced to the R(56)32-0: a1 hyperfine transition of molecular iodine based on modulation transfer spectroscopy. We design an unsaturated iodine vapor cell with a gas pressure equivalent to the saturation pressure at −17 °C. Using this cell, we developed a compact, frequency-stabilized laser. The iodine cell operates at room temperature and is not actively temperature stabilized. We demonstrate a laser with fractional frequency instability of 1.4 × 10−14 at 1 s and 1.7 × 10−15 at 104 s. To our knowledge, the level of frequency instability at 104 s is comparable to the previously reported best results for an iodine stabilized laser. These results suggest that using an unsaturated iodine vapor cell is a valid approach for the development of long-term, stable iodine-based optical references. [ABSTRACT FROM AUTHOR]

Many space based gravity missions require frequency stabilized lasers with stringent requirements. Toward those requirements, we develop a compact frequency-stabilized laser which is referenced to the R(56)32−0: a1 transition of molecular iodine based on the modulation transfer spectroscopy technique. The stability of the laser is limited by the beam pointing noise, the electronic servo noise, and the residual amplitude modulation (RAM) noise. To improve the beam pointing stability, the system is constructed by gluing most components of the optical system on an ultra-low expansion glass base. We use a pre-amplifier to suppress the electronic servo noise, and use a wedged electro-optic phase modulator to suppress the RAM noise. The fractional frequency instability of the system is evaluated to be 3.3 × 10−15 at 2 s and 4 s averaging time, and is lower than 6 × 10−15 at averaging times from 1 s to 10 000 s. To our knowledge, this is the best short-term (1–4 s) instability reported so far for an iodine stabilized laser. The stability fully meets the requirements of next generation gravity mission and laser interferometer space antenna mission. [ABSTRACT FROM AUTHOR]

Net ecosystem productivity ( NEP) represents the carbon sequestration capacity of a regional ecosystem. Based on the Google Earth Engine ( GEE) platform, this study analyzed the temporal and spatial variations in the NEP of the Three - River Headwaters Region ( TRHR) from 2001 to 2020 based on the Moderate Resolution Imaging Spectrometer ( MODIS) and meteorological data and revealed their relationships with climate factors. The results are as follows; 1 The TRHR had an important carbon sink function, with carbon sink areas accounting for 99. 89% ; The carbon source areas in the TRHR were primarily distributed in the northwest, accounting for only 0. 11%. The NEP of the TRHR decreased gradually from the southeast to the northwest and differed significantly among different ecological areas; 2 The NEP of the TRHR showed an upward trend overaU in the past 20 years, with an annual increasing rate of 1. 13 gC/(m ² • a), indicating huge carbon sequestration potential; 3 The area of zones whose NEP showed an upward trend accounted for 95. 05% of the total area. Ecological engineering construction significantly improved the NEP of vegetation. As a result, the carbon sink function gradually increased and was highly stable; 4 The TRHR had an annual average NEP of 120. 93 gC/( m ² • a), and the NEP was positively correlated with the annual precipitation but negatively correlated with average annual temperature and annual solar radiation. The warm, humid climate and the ecological engineering construction contributed to the carbon sink function of vegetation in the TRHR. This is of great significance for improving the carbon sink value of the terrestrial ecosystem and achieving the peak carbon dioxide emissions and carbon neutrality of China. [ABSTRACT FROM AUTHOR]

Carbonyl iron powder–polymer coating is one of the effective microwave absorption systems, which can be widely used as medium temperature structural materials in the aerospace industry. However, the significant mismatch of the coefficient of thermal expansion (CTE) between coatings and the titanium alloy substrates will cause serious cracking and peeling problems in practical applications. Thus, we designed to introduce Y2Mo3O12 (YMO) with negative CET into the carbonyl iron powder–boron-modified phenolic (BP) resin coating to reduce the CET of coating. The result showed that the CTE of the coatings is significantly decreased by the addition of Y2Mo3O12. The YMO/CIP/BP coating of 8 wt% YMO - 67 wt% CIP - 25 wt% BP shows a CTE of 21.1 × 10–6 ℃−1, which is 68% smaller than that of CIP/BP coating. The minimum RL (maximum of microwave absorption) of 8 wt% YMO - 67 wt% CIP - 25 wt% BP is – 12.3 dB at the thickness of 1.4 mm, which makes it an excellent candidate for the microwave absorptions applied on the titanium alloy surfaces. [ABSTRACT FROM AUTHOR]

Purpose: The genomic characteristics of uterine sarcomas have not been fully elucidated. This study aimed to explore the genomic landscape of the USs., Materials and Methods: Comprehensive genomic analysis through RNA-sequencing was conducted. Gene fusion, differentially expressed genes (DEGs), signaling pathway enrichment, immune cell infiltration, and prognosis were analyzed. A deep learning model was constructed to predict the survival of US patients., Results: A total of 71 US samples were examined, including 47 endometrial stromal sarcomas (ESS), 18 uterine leiomyosarcomas (uLMS), 3 adenosarcomas, 2 carcinosarcomas, and 1 uterine tumor resembling an ovarian sex-cord tumor (UTROSCT). ESS (including high-grade ESS and low-grade ESS) and uLMS showed distinct gene fusion signatures; a novel gene fusion site, MRPS18A - PDC-AS1 could be a potential diagnostic marker for the pathology differential diagnosis of uLMS and ESS; 797 and 477 uDEGs were identified in the ESS vs. uLMS and HGESS vs. LGESS groups, respectively. The uDEGs were enriched in multiple pathways. Fifteen genes including LAMB4 were confirmed with prognostic value in USs; immune infiltration analysis revealed the prognositic value of myeloid dendritic cells, plasmacytoid dendritic cells, natural killer cells, macrophage M1, monocytes and hematopoietic stem cells in USs; the deep learning model named MMN-MIL showed satisfactory performance in predicting the survival of US patients, with the area under the receiver operating curve curve reached 0.909 and accuracy achieved 0.804., Conclusion: USs harbored distinct gene fusion characteristics and gene expression features between HGESS, LGESS, and uLMS. The MMN-MIL model could effectively predict the survival of US patients.

Background: Capsule-preserving hydrodilatation is a common treatment for adhesive capsulitis (AC), and ultrasound (US) has recently become the most popular adjuvant tool for image-guided glenohumeral joint injection. However, traditional US is hardly adequate to assess extracapsular fluid leakage, which may decide the treatment outcomes. In this study, we explored the value of contrast-enhanced ultrasound (CEUS) guided capsule-preserving hydrodilatation with steroids and ultrasonic contrast agents for treatment of AC., Methods: A total of 40 consecutive patients with AC were prospectively enrolled and received CEUS-guided capsule-preserving hydrodilatation. The number of injection attempts, injection volume, and fluid leakage were recorded, and the correlations with clinical features were analyzed by Pearson or Spearman correlation coefficients. Outcome measures including visual analog scale (VAS) score, passive range of motion (ROM), and shoulder pain and disability index (SPADI) score were evaluated at baseline and 4 weeks after treatment. Comparisons between patients with good and poor clinical outcomes were performed with independent t -test, Mann-Whitney U test, and chi-square test. Logistic regression was used to identify predictors of good clinical outcomes. A P value <0.05 defined significance., Results: Access to the glenohumeral joint was successful in 87.5% patients on the first attempt. The infused fluid volume was 21.0±3.40 mL. Longer symptom duration (r=-0.676, P<0.001), greater SPADI (r=-0.148, P=0.007), and decreased ROM in abduction (r=0.38, P=0.016) were associated with a decreased volume of infused fluid. CEUS detected massive fluid leakage in 5 (12.5%) patients, with 4 capsule ruptures confirmed by magnetic resonance imaging (MRI). Longer symptom duration (r=0.485, P=0.001), decreased ROM in the direction of abduction (r=-0.33, P=0.037), and external rotation (r=-0.34, P=0.032) were correlated with an increased incidence of massive fluid leakage. Moreover, patients with good outcomes had significantly shorter symptom duration (5.7±2.09 vs . 11.2±3.89 months, P=0.002) and greater initial VAS score (6.9±1.04 vs . 6.3±0.50, P=0.022) than those with poor outcomes. Absence of massive fluid leakage was an independent predictor of clinical good outcomes at 4 weeks after treatment [odd ratio (OR) =0.05, 95% confidential interval (CI): 0.003-0.882, P=0.041]., Conclusions: CEUS-guided capsule-preserving hydrodilatation allows real-time visualization of capsule dilatation, accurate detection of extracapsular fluid leakage, and identification of risks for capsule rupture. It provides an effective treatment for AC, and is useful to predict patients' clinical outcomes., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://qims.amegroups.com/article/view/10.21037/qims-24-39/coif). The authors have no conflicts of interest to declare., (2024 Quantitative Imaging in Medicine and Surgery. All rights reserved.)

In this work, we experimentally perform time delay interferometry by using a transfer oscillator, which is capable of reducing the laser frequency noise and the clock noise simultaneously in the post processing. The iodine frequency reference is coherently downconverted to the microwave frequency using a laser frequency comb. The residual noise of the downconversion network is 5 × 10 -6 Hz/Hz 1/2 at 0.7 mHz, and 4 × 10 -6 Hz/Hz 1/2 at 0.1 Hz, indicating high homology between the optical frequency and the microwave frequency. We carry out time delay interferometry with the aid of the electrical delay module, which can introduce large time delays. The results show that the laser frequency noise and the clock noise can be reduced simultaneously by ten and three orders of magnitude, respectively, in the frequency band from 0.1 mHz to 0.1 Hz. The performance of the noise reduction can reach 6 × 10 -8 Hz/Hz 1/2 at 0.1 mHz, and 7 × 10 -7 Hz/Hz 1/2 at 1 mHz, meeting the requirements of the space-borne gravitational wave detection. Our work will be able to offer an alternative method for the frequency comb-based time delay interferometry in the future space-borne gravitational wave detectors.

The detection of biomolecular analytes is of great importance in clinical, environmental, and argo-food areas, among which the electrochemical methodology is attracting much attention. In particular, screen-printed electrode (SPE)-based sensing applications have exhibited potential possibility for on-site detection, especially for fast clinical biomarker detection, since they provide a miniaturized but robust and portable electrode detection system. In this context, we focused on the modification of SPE with functional antibodies to improve the electrochemical detection performance in versatile sensing applications, particularly for COVID-19 detection. These antibodies were immobilized onto the electrode surface via various methodologies, through which the powerful potential from the modification of SPE was revealed. Finally, more novel and excellent works on the biomolecular modification of SPE and the prospects of this technology from its state-of-art status to commercialization are previewed and future perspectives in this field are mentioned.