[Prognostic value of skeletal muscle measured by CT at the T4 level in advanced EGFR-positive non-small cell lung cancer patients treated with ecotinib]

Objective: To investigate the prognostic value of skeletal muscle measured by CT at the level of the fourth thoracic vertebra (T4) in advanced epidermal growth factor receptor (EGFR)-positive non-small cell lung cancer (NSCLC) patients treated with ecotinib. Methods: The study retrospectively reviewed clinical and pathological characteristics of 176 patients with advanced EGFR-positive NSCLC who received ecotinib and underwent chest CT scans at Wuhan Union Hospital between January 2017 and October 2020. Among them, 70 were male and 106 were female, with ages ranging from 27 to 80 (58.6±10.6) years. As of August 21, 2021, the median follow-up duration was 19.2 months (95%CI: 15.3 to 23.7 months). The optimal cut-off value of skeletal muscle density (T4-SMD) on CT images at the T4 level were determined using X-tile software. Kaplan-Meier analysis and log-rank test were used to plot progression-free survival curves. Cox proportional hazards regression models were employed to analyze factors influencing 1-year progression-free survival (PFS), and a nomogram prognostic model was constructed accordingly. Receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA) were utilized to evaluate the predictive value of the nomogram. Results: The T4-SMD [M (Q1,Q3)] of 176 patients was 42.56 (37.05, 45.93) HU. Patients were divided into low T4-SMD group (n=122) and high T4-SMD group (n=54) based on the cut-off value (The values for males and females were 49.44 and 41.41 HU, respectively) of T4-SMD. The median PFS time and 1-year PFS rate in the low T4-SMD group were significantly lower than those in the high T4-SMD group [10.4 (95%CI: 9.3-11.8) vs 13.7 (95%CI: 11.1-18.5) months, 36.1% vs 59.3%, respectively, P=0.034]. Eastern Cooperative Oncology Group performance status (HR=3.308, 95%CI: 1.183-9.247, P=0.023), lactate dehydrogenase level (HR=1.852, 95%CI: 1.037-3.307, P=0.037), systemic immune-inflammation index (HR=1.772, 95%CI: 1.019-3.080, P=0.043), and T4-SMD (HR=0.563, 95%CI: 0.325-0.974, P=0.040) were prognostic factors for 1-year PFS in advanced EGFR-positive NSCLC patients treated with ecotinib. A nomogram for predicting 1-year PFS of advanced EGFR-positive NSCLC patients treated with ecotinib was constructed based on the four indicators selected by multivariate Cox regression analysis. The area under the ROC curve of the nomogram was 0.775 (95%CI: 0.676-0.874). The calibration curve showed good consistency between the predicted and actual 1-year PFS. DCA demonstrated good clinical prediction effectiveness of the nomogram. Conclusion: Low T4-SMD is a prognostic risk factor for patients with advanced EGFR-positive NSCLC receiving icotinib therapy.

Targeted metabolomic profiles of serum amino acids are independently correlated with malnutrition in older adults

BACKGROUND

Malnutrition is a common geriatric syndrome that is closely associated with adverse clinical outcomes and poses significant harm to older adults. Early assessment of nutritional status plays a crucial role in preventing and intervening in cases of malnutrition. However, there is currently a lack of measurable methods and biomarkers to evaluate malnutrition in older adults accurately. The aim of this study is to investigate the independent correlation between serum levels of amino acids and malnutrition in older adults, and to identify effective metabolomics biomarkers that can aid in the early detection of geriatric malnutrition.

METHODS

A total of 254 geriatric medical examination participants from Beijing Hospital were included in the study, consisting of 182 individuals with normal nutritional status (Normal group) and 72 patients at risk of malnutrition or already malnourished (MN group). Malnutrition was assessed using the Mini-Nutritional Assessment Short-Form (MNA-SF). Demographic data were collected, and muscle-related and lipid indexes were determined. Serum amino acid concentrations were measured using isotope dilution liquid chromatography-tandem mass spectrometry (LC-MS/MS). The correlation between serum amino acid levels and malnutrition was analyzed using non-parametric tests, partial correlation analysis, linear regression, and logistic regression.

RESULTS

The geriatric MN group exhibited significantly lower serum aromatic amino acid levels (P < 0.05) compared to the normal group. A positive correlation was observed between serum aromatic amino acid levels and the MNA-SF score (P = 0.002), as well as with known biomarkers of malnutrition such as body mass index (BMI) (P < 0.001) and hemoglobin (HGB) (P = 0.005). Multivariable logistic or linear regression analyses showed that aromatic amino acid levels were negatively correlated with MN and positively correlated with the MNA-SF score, after adjusting for some confounding factors, such as age, gender, BMI, smoking status, history of dyslipidemia, diabetes mellitus and frailty. Stratified analyses revealed that these trends were more pronounced in individuals without a history of frailty compared to those with a history of frailty, and there was an interaction between aromatic amino acid levels and frailty history (P = 0.004).

CONCLUSION

Our study suggests that serum aromatic amino acids are independently associated with malnutrition in older adults. These results have important implications for identifying potential biomarkers to predict geriatric malnutrition or monitor its progression and severity, as malnutrition can result in poor clinical outcomes.

Xylan-directed cell wall assembly in grasses

Xylan is the most abundant hemicellulosic polysaccharide in the cell walls of grasses and is pivotal for the assembly of distinct cell wall structures that govern various cellular functions. Xylan also plays a crucial role in regulating biomass recalcitrance, ultimately affecting the utilization potential of lignocellulosic materials. Over the past decades, our understanding of the xylan biosynthetic machinery and cell wall organization has substantially improved due to the innovative application of multiple state-of-the-art techniques. Notably, novel xylan-based nanostructures have been revealed in the cell walls of xylem vessels, promoting a more extensive exploration of the role of xylan in the formation of cell wall structures. This Update summarizes recent achievements in understanding xylan biosynthesis, modification, modeling, and compartmentalization in grasses, providing a brief overview of cell wall assembly regarding xylan. We also discuss the potential for tailoring xylan to facilitate the breeding of elite energy and feed crops.

Design of Single-Atom Catalysts for E lectrocatalytic Nitrogen Fixation

The Electrochemical nitrogen reduction reaction (ENRR) can be used to solve environmental problems as well as energy shortage. However, ENRR still faces the problems of low NH3 yield and low selectivity. The NH3 yield and selectivity in ENRR are affected by multiple factors such as electrolytic cells, electrolytes, and catalysts, etc. Among these catalysts are at the core of ENRR research. Single-atom catalysts (SACs) with intrinsic activity have become an emerging technology for numerous energy regeneration, including ENRR. In particular, regulating the microenvironment of SACs (hydrogen evolution reaction inhibition, carrier engineering, metal-carrier interaction, etc.) can break through the limitation of intrinsic activity of SACs. Therefore, this Review first introduces the basic principles of NRR and outlines the key factors affecting ENRR. Then a comprehensive summary is given of the progress of SACs (precious metals, non-precious metals, non-metallic) and diatomic catalysts (DACs) in ENRR. The impact of SACs microenvironmental regulation on ENRR is highlighted. Finally, further research directions for SACs in ENRR are discussed.

A system dynamics simulation-based strategic analysis of integrated water resources utilization and management in Shenzhen city

As one of the most rapidly developing cities in China, Shenzhen grapples with an increasing challenge in managing water resources due to escalating conflicts with its soaring water demand. This study established a system dynamics (SD) model based on a causal loop diagram to explore the intricate interconnections within the urban water resources system. Through simulating water supply and demand in Shenzhen from 2021 to 2035, the model identified key sensitive factors and examined various utilization scenarios for multiple water resources. Results indicated that water scarcity posed a significant obstacle to Shenzhen's development. To tackle this challenge, several effective measures should be implemented, including enhancing water conservation capabilities, developing seawater resources, promoting water reuse, optimizing the economic structure, and managing population growth. Prioritizing water conservation efforts and maximizing the utilization of seawater resources were regarded as the most impactful strategies in alleviating the water crisis. Furthermore, the relationship between water conservation capabilities and seawater utilization scale was analyzed using the SD model, contributing to the development of a comprehensive water resources management strategy. The findings from this study would provide insights into robust methods for allocating water resources, thereby enhancing sustainable water management strategies applicable to regions facing similar challenges.

Construction of an instrument to enable the assessment of the risk of falls in older outpatients: A quantitative methodological study

OBJECTIVES

To develop an instrument to facilitate the risk assessment of falls in older outpatients.

DESIGN

A quantitative methodological study using the cross-sectional data.

METHODS

This study enrolled 1988 older participants who underwent comprehensive geriatric assessment (CGA) in an outpatient clinic from May 2020 to November 2022. The history of any falls (≥1 falls in a year) and recurrent falls (≥2 falls in a year) were investigated. Potential risk factors of falls were selected by stepwise logistic regression, and a screening tool was constructed based on nomogram. The tool performance was compared with two reference tools (Fried Frailty Phenotype; CGA with 10 items, CGA-10) by using receiver operating curves, sensitivity (Sen), specificity (Spe), and area under the curve (AUC).

RESULTS

Age, unintentional weight loss, depression measured by the Patient Health Questionnaire-2, muscle strength measured by the five times sit-to-stand test, and stand balance measured by semi- and full-tandem standing were the most important risk factors for falls. A fall risk screening tool was constructed with the six measurements (FRST-6). FRST-6 showed the best AUC (Sen, Spe) of 0.75 (Sen = 0.72, Spe = 0.69) for recurrent falls and 0.65 (Sen = 0.74, Spe = 0.48) for any falls. FRST-6 was comparable to CGA-10 and outperformed FFP in performance.

CONCLUSIONS

Age, depression, weight loss, gait, and balance were important risk factors of falls. The FRST-6 tool based on these factors showed acceptable performance in risk stratification.

IMPACT

Performing a multifactorial assessment in primary care clinics is urgent for falls prevention. The FRST-6 provides a simple and practical way for falls risk screening. With this tool, healthcare professionals can efficiently identify patients at risk of falling and make appropriate recommendations in resource-limited settings.

PATIENT OR PUBLIC CONTRIBUTION

No patient or public contribution was received, due to our study design.

Ligand Defect-Induced Active Sites in Ni-MOF-74 for Efficient Photocatalytic CO2 Reduction to CO

The conversion of CO2 into valuable carbon-based products using clean and renewable solar energy has been a significant challenge in photocatalysis. It is of paramount importance to develop efficient photocatalysts for the catalytic conversion of CO2 using visible light. In this study, the Ni-MOF-74 material is successfully modified to achieve a highly porous structure (Ni-74-Am) through temperature and solvent modulation. Compared to the original Ni-MOF-74, Ni-74-Am contains more unsaturated Ni active sites resulting from defects, thereby enhancing the performance of CO2 photocatalytic conversion. Remarkably, Ni-74-Am exhibits outstanding photocatalytic performance, with a CO generation rate of 1380 µmol g-1 h-1 and 94% CO selectivity under visible light, significantly surpassing the majority of MOF-based photocatalysts reported to date. Furthermore, experimental characterizations reveal that Ni-74-Am has significantly higher efficiency of photogenerated electron-hole separation and faster carrier migration rate for photocatalytic CO2 reduction. This work enriches the design and application of defective MOFs and provides new insights into the design of MOF-based photocatalysts for renewable energy and environmental sustainability. The findings of this study hold significant promise for developing efficient photocatalysts for CO2 reduction under visible-light conditions.

Autonomous State Estimation and Observability Analysis for the Taiji Formation Using High-Precision Optical Sensors

In certain observation periods of navigation missions for the Taiji formation, ground observation stations are unable to observe the spacecraft, while the state of the spacecraft can be estimated through the utilization of dynamic equations simulated on prior knowledge. However, this method cannot accurately track the spacecraft. In this paper, we focus on appropriately selecting the available onboard measurement to estimate the state of the spacecraft of the Taiji formation. We design two schemes to explore the performance of the state estimation based on the interspacecraft interferometry measurements and the measurements obtained from the Sun sensor and the radial velocity sensor. The observability of the system is numerically analyzed using the singular value decomposition method. Furthermore, we analyze error covariance propagation using the cubature Kalman filter. The results show that using high-precision interspacecraft angle measurement can improve significantly the observability of the system. The absolute position and velocity of the spacecraft can be estimated respectively with an accuracy of about 3.1 km and 0.14 m/s in the first scheme, where the prior information of the precision of the position and velocity is respectively 100 km and 1 m/s. When the measurement from the radial velocity sensor is used in the second scheme, the estimation accuracy of the velocity can be improved about 18 times better than that in the first scheme.

A Physics-Informed Automatic Neural Network Generation Framework for Emerging Device Modeling

With the rapid development of semiconductor technology, traditional equation-based modeling faces challenges in accuracy and development time. To overcome these limitations, neural network (NN)-based modeling methods have been proposed. However, the NN-based compact model encounters two major issues. Firstly, it exhibits unphysical behaviors such as un-smoothness and non-monotonicity, which hinder its practical use. Secondly, finding an appropriate NN structure with high accuracy requires expertise and is time-consuming. In this paper, we propose an Automatic Physical-Informed Neural Network (AutoPINN) generation framework to solve these challenges. The framework consists of two parts: the Physics-Informed Neural Network (PINN) and the two-step Automatic Neural Network (AutoNN). The PINN is introduced to resolve unphysical issues by incorporating physical information. The AutoNN assists the PINN in automatically determining an optimal structure without human involvement. We evaluate the proposed AutoPINN framework on the gate-all-around transistor device. The results demonstrate that AutoPINN achieves an error of less than 0.05%. The generalization of our NN is promising, as validated by the test error and the loss landscape. The results demonstrate smoothness in high-order derivatives, and the monotonicity can be well-preserved. We believe that this work has the potential to accelerate the development and simulation process of emerging devices.

[A conceptual framework for dynamics of cccDNA in hepatitis B virus]

The resolution of the hepatitis C issue has raised expectations for a chronic hepatitis B cure, driving the industry to expand investment in research and development efforts to strengthen functional cure strategies. These strategies have a wide variety of types, and the published research findings are heterogeneous. The theoretical analysis of these strategies is of great significance for determining prioritized research orientations as well as sensibly allocating research and development resources. However, due to a paucity of necessary conceptual models, current theoretical analysis has not been able to unify various therapeutic strategies into a proper theoretical framework. In view of the fact that the decrease in the quantity of cccDNA is an inevitable core event accompanied by the process of functional cure, this paper intends to analyze several chronic hepatitis B cure strategies using cccDNA dynamics as a framework. Furthermore, there are currently few studies on the dynamics of the cccDNA field, hoping that this article can promote recognition and research in this field.

Reconstructing the earliest known composite-tiled roofs from the Chinese Loess Plateau

The origins of composite tiles, one of the oldest forms of roofing, are still unclear. This study is based on a set of over 5000 clay tile fragments excavated from a single context in the Qiaocun site on the Chinese Loess Plateau, dated to ~ 2400-2200 BCE (Early Longshan Period). By combining morphological measurement statistics, 3D modeling, computer-based simulations, and reference to historical and archaeological records, we reconstruct the earliest known composite-tile roofing techniques and demonstrate that tile production was under a low-level standardization, with manual control forming a key agent during the roofing process. The quantitative study of the composite roof tiles from Qiaocun was then placed in its archaeological context and compared with other sites on the Loess Plateau. It was found that tile-roofed buildings were, by necessity, community projects. Such structures served as nodes in larger social communication networks; additionally, their appearance was linked to intensified social complexity in public affairs during the Longshan Period. The invention of clay tiles was associated with the inception of thick rammed-earth walls which had sufficient strength to serve as load-bearing structures for heavy tiled roofs. The roof tiles excavated from Qiaocun site indicate that the Loess Plateau was a key center for the origin and spread of composite tiles and related roofing and construction methods, suggesting a Longshan-Western Zhou tradition of roofing techniques in East Asia.

Dppa3 Improves the Germline Competence of Pluripotent Stem Cells

BACKGROUND

Chimera formation and germline competence are critical features of mouse pluripotent stem cells (PSCs). However, the factors that contribute to germline competence in the chimeras remain to be understood.

METHODS

To determine the role of Dppa3 in PSCs, we first constructed Dppa3 knockout (Dppa3 KO) and Dppa3 overexpression (Dppa3 OE) PSCs, respectively. Using Dppa3 KO and Dppa3 OE PSCs, we then investigated the role of Dppa3 in PSCs by evaluating the chimera generation, DNA methylation, and pluripotent state conversion.

RESULTS

We show that Dppa3 plays an important role in chimera formation and germline competence of mouse PSCs. PSC lines with high expression of Dppa3 show high germline competence. In contrast, Dppa3 deficiency reduces chimera formation and abrogates the germline transmission capacity of PSCs. Molecularly, Dppa3 facilitates establishing global DNA hypomethylation in PSCs. High levels of Dppa3 in PSCs reduce the expression of Dnmt3a/b and impede Uhrf1-Dnmt1 complex binding to DNA replication forks, maintaining DNA hypomethylation. Additionally, Dppa3 facilitates two-cell-stage (2C) genes expression and promotes conversion to a 2C-like state.

CONCLUSION

These data show that Dppa3 is involved in maintaining DNA hypomethylation homeostasis and is required for high chimera formation and germline competence of PSCs.

[Prevention of adverse prognosis of malignant melanoma from the point of evolution of surgical margin]

Treating malignant melanoma of skin at the early stage depends on wide excision mainly. For the prevention of tumor recurrence, means of acquisition of the safe margin changed from empirical resection to accurate pathological evaluation, and therapeutic target evolved from clearing tumor cells to pursuing the best prognosis. In the future, it would be necessary to combine individualized treatment with evidence-based medicine in the treatment of cutaneous malignant melanoma to prevent adverse outcomes.