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I-line stepper is widely used in large scale device manufacturing with limited achievable critical dimension by itself. With the aid of the spacer sidewall, the critical dimension can be further shrunk down. Spacer sidewall aided process necessitates an additional deposition-etching process, which inevitably results in process related damage under the gate. This paper proposes an optimized spacer sidewall aided gate patterning procedure for 0.15 μm GaN High Electron Mobility Transistors (HEMTs) fabrication. The process is proved to be effective in improving device performance compared to conventional sidewall process by keeping first Si-rich SiN passivation layer integrity at the gate edge. Interface trap density (Dit) and mobility were extracted for both conventional sidewall process and the optimized one with different passivation layers at the gate edge, demonstrating a lower Dit and higher mobility using the optimized process with enhanced device performances, such as higher current, breakdown voltage, and stress state characteristics, compared to the conventional process, which is promising for mass production of 0.15 μm GaN HEMTs. [ABSTRACT FROM AUTHOR]

We investigate the dynamics of Landau–Zener (LZ) transitions in an anisotropic, dissipative three-level LZ model (3-LZM) using the numerically accurate multiple Davydov D2Ansatz in the framework of the time-dependent variational principle. It is demonstrated that a non-monotonic relationship exists between the Landau–Zener transition probability and the phonon coupling strength when the 3-LZM is driven by a linear external field. Under the influence of a periodic driving field, phonon coupling may induce peaks in contour plots of the transition probability when the magnitude of the system anisotropy matches the phonon frequency. The 3-LZM coupled to a super-Ohmic phonon bath and driven by a periodic external field exhibits periodic population dynamics in which the period and amplitude of the oscillations decrease with the bath coupling strength. [ABSTRACT FROM AUTHOR]

Breast tumor‐initiating cells (BTICs) of triple‐negative breast cancer (TNBC) tissues actively repair DNA and are resistant to treatments including chemotherapy, radiotherapy, and targeted therapy. Herein, it is found that a previously reported secreted protein, sclerostin domain containing 1 (SOSTDC1), is abundantly expressed in BTICs of TNBC cells and positively correlated with a poor patient prognosis. SOSTDC1 knockdown impairs homologous recombination (HR) repair, BTIC maintenance, and sensitized bulk cells and BTICs to Olaparib. Mechanistically, following Olaparib treatment, SOSTDC1 translocates to the nucleus in an importin‐α dependent manner. Nuclear SOSTDC1 interacts with the N‐terminus of the nucleoprotein, chromatin helicase DNA‐binding factor (CHD1), to promote HR repair and BTIC maintenance. Furthermore, nuclear SOSTDC1 bound to β‐transducin repeat‐containing protein (β‐TrCP) binding motifs of CHD1 is found, thereby blocking the β‐TrCP‐CHD1 interaction and inhibiting β‐TrCP‐mediated CHD1 ubiquitination and degradation. Collectively, these findings identify a novel nuclear SOSTDC1 pathway in regulating HR repair and BTIC maintenance, providing insight into the TNBC therapeutic strategies. [ABSTRACT FROM AUTHOR]

Mn/TiO2 and Fe–Mn/TiO2 catalysts were prepared using the impregnation method to explore the effect of iron doping at low temperature on the catalytic oxidation of high concentration NO by manganese-based catalysts and the catalytic reaction mechanism. This study reveals that the Fe–Mn/TiO2 catalyst performed exceptionally well in catalyzing high concentration NO smelting flue gas within a temperature range of 30–170 °C. At 150 °C, the denitrification efficiency of Fe–Mn/TiO2 (0.3) catalyst was 97.7%. Characterization analysis revealed that the incorporation of iron increased the ratio of high valence manganese and surface chemisorbed oxygen, which promoted the dispersion of surface-active substances, ultimately leading to an increase in the specific surface area of the catalyst. These factors facilitated the adsorption and activation of NH3 as well as the oxidation of NO to NO2, thus increasing the low-temperature redox capacity of the catalyst. Meanwhile, the ammonia selective catalytic reduction (NH3-SCR) denitrification mechanism over Fe–Mn/TiO2 catalysts was consistent with the Eley–Rideal (E–R) and Langmuir–Hinshelwood (L–H) mechanisms under low-temperature reaction conditions. [ABSTRACT FROM AUTHOR]

Tumor-resident microbiota in breast cancer promotes cancer initiation and malignant progression. However, targeting microbiota to improve the effects of breast cancer therapy has not been investigated in detail. Here, we evaluated the microbiota composition of breast tumors and found that enterotoxigenic Bacteroides fragilis (ETBF) was highly enriched in the tumors of patients who did not respond to taxane-based neoadjuvant chemotherapy. ETBF, albeit at low biomass, secreted the toxic protein BFT-1 to promote breast cancer cell stemness and chemoresistance. Mechanistic studies showed that BFT-1 directly bound to NOD1 and stabilized NOD1 protein. NOD1 was highly expressed on ALDH+ breast cancer stem cells (BCSCs) and cooperated with GAK to phosphorylate NUMB and promote its lysosomal degradation, thereby activating the NOTCH1-HEY1 signaling pathway to increase BCSCs. NOD1 inhibition and ETBF clearance increase the chemosensitivity of breast cancer by impairing BCSCs. [ABSTRACT FROM AUTHOR]

Phosphorus (P) is a non-renewable resource, therefore ensuring global food and environmental security depends upon sustainable P management. To achieve this goal, sustainable P management in the upstream and downstream sectors of agriculture from mineral extraction to food consumption must be addressed systematically. The innovation and feasibility of P sustainability are highlighted from the perspective of the whole P-based chain, including the mining and processing of P rock, production of P fertilizers, soil and rhizosphere processes involving P, absorption and utilization of P by plants, P in livestock production, as well as flow and management of P at the catchment scale. The paper also emphasizes the importance of recycling P and the current challenges of P recovery. Finally, sustainable solutions of holistic P management are proposed from the perspective of technology improvement with policy support.

Landau‐Zener (LZ) transitions in the three‐level bow‐tie model (3L‐BTM) in a dissipative environment are investigated by using the numerically accurate method of multiple Davydov D2$\mathrm{D}_{2}$ Ansätze. The 3L‐BTM coupled to a single harmonic mode is first considered, and evolutions of transition probabilities for selected values of model parameters are studied and interpreted with the aid of the energy diagram method. Then the 3L‐BTM coupled to a boson bath of a continuum spectral density is explored. The simulations demonstrate that sub‐Ohmic, Ohmic and super‐Ohmic boson baths have substantially different influences on the 3L‐BTM dynamics, which cannot be grasped by the standard phenomenological Markovian single‐rate descriptions. Novel bath‐induced phenomena are also described, which are absent in two‐level LZ systems. [ABSTRACT FROM AUTHOR]

The Sanggan River Basin in the loess hill and gully area is the primary water source for the establishment of the capital water conservation function area and the ecological environment support zone. Against the backdrop of global warming, population growth, and accelerated urbanization, water consumption in the Sanggan River Basin has persistently increased in recent years, leading to a series of issues, such as river pollution, surface streamflow reduction, groundwater over-exploitation, soil erosion, and decreased vegetation coverage. In this research, we employed the DMC approach, SWAT model, InVEST model, and CA-Markov model to quantitatively analyze the correlation between alterations in streamflow and sediment within this area and three influential factors: climate variations, LUCC, and other human interventions. Furthermore, we clarified the relative contributions of climate factor elements, land-use types, and human activities to streamflow and sediment in this region. The findings indicate a decline in the annual streamflow and sediment quantities observed within this region from 1960 to 2020, with reduction rates of 1.27 × 108 m3/10 a and 129.07 × 104 t/10 a, respectively, and an abrupt change year in 1983 and 1982. Compared to the annual streamflow, the annual sediment volume demonstrates more substantial variation. Based on the constructed model, three scenario simulation periods: P0 (1962–1981/1982), P1 (1983/1982–1999), and P2 (2000–2020) were set. Compared with P0, the respective contribution rates of climatic variation, land use, and other human intervention to streamflow (sediment volume) were 15.247% (19.601%), −0.03% (−1.349%), and 84.783% (81.748%) in P1. In P2, the contribution rates of these three factors on streamflow (sediment volume) were 9.160% (9.128%), 0.211% (3.053%), and 90.629% (84.818%), respectively. Through a quantitative analysis of climatic factors on streamflow and sediment, we found a positive correlation between precipitation and both streamflow and sediment. Additionally, there is an inverse relationship between temperature and streamflow, but streamflow will increase when temperature rises by 10%. Under three different future land-use scenarios, the variations in streamflow and sediment exhibited as ecological protection scenario < urban expansion scenario < natural development scenario. Changes in streamflow in this region are primarily caused by human intervention that alters the underlying surface. The increase in check dams and silted land could lead the runoff and sediment to decrease. Moreover, compared with the increase in industrial and agricultural water consumption, the increase in urban water consumption is the main factor for human water consumption. [ABSTRACT FROM AUTHOR]

The InAlN/GaN HEMT has been identified as a promising alternative to conventional AlGaN/GaN HEMT due to its enhanced polarization effect contributing to higher 2DEG in the GaN channel. However, the InAlN barrier usually suffers from high leakage and therefore low breakdown voltage. In this paper, we propose an asymmetrical GaN HEMT structure which is composed of an InAlN barrier at the source side and an AlGaN barrier at the drain side. This novel device combines the advantages of high 2DEG density at the source side and low electrical-field crowding at the drain side. According to the TCAD simulation, the proposed asymmetric device exhibits better drain current and transconductance compared to AlGaN/GaN HEMT, and enhanced breakdown voltage compared to InAlN/GaN HEMT. The current collapse effects have also been evaluated from the process-related point of view. Possible higher interface traps related to the two-step epitaxial growth for the asymmetric structure fabrication will not exacerbate the current collapse and reliability. [ABSTRACT FROM AUTHOR]

In this letter, molybdenum nitride (MoN) gate AlGaN/GaN HEMT has been investigated with MoN developed in various physical vapour deposition (PVD) conditions. The Schottky gate is studied through forward and reverse characteristics with different processed MoN, which is compared with the standard Ni gate. Similar DC and radio frequency (RF) performances are obtained with MoN and Ni gate, while MoN demonstrated higher reliability than Ni gate through RF aging test. [ABSTRACT FROM AUTHOR]

The family of aldehyde dehydrogenases (ALDHs) contains 19 isozymes and is involved in the oxidation of endogenous and exogenous aldehydes to carboxylic acids, which contributes to cellular and tissue homeostasis. ALDHs play essential parts in detoxification, biosynthesis, and antioxidants, which are of important value for cell proliferation, differentiation, and survival in normal body tissues. However, ALDHs are frequently dysregulated and associated with various diseases like Alzheimer's disease, Parkinson's disease, and especially solid tumors. Notably, the involvement of the ALDHs in tumor progression is responsible for the maintenance of the stem‐cell‐like phenotype, triggering rapid and aggressive clinical progressions. ALDHs have captured increasing attention as biomarkers for disease diagnosis and prognosis. Nevertheless, these require further longitudinal clinical studies in large populations for broad application. This review summarizes our current knowledge regarding ALDHs as potential biomarkers in tumors and several non‐tumor diseases, as well as recent advances in our understanding of the functions and underlying molecular mechanisms of ALDHs in disease development. Finally, we discuss the therapeutic potential of ALDHs in diseases, especially in tumor therapy with an emphasis on their clinical implications. [ABSTRACT FROM AUTHOR]

Healing of full-thickness skin wounds remains a major challenge. Recently, human umbilical cord mesenchymal stem cells (hUC-MSCs) were shown to possess an extraordinary potential to promote skin repair in clinical settings. However, their low survival rate after transplantation limits their therapeutic efficiency in treating full-thickness skin wounds. Hydrogels are considered an ideal cell transplantation vector owing to their three-dimensional mesh structure, good biosafety, and biodegradation. The objective of this study was to investigate the skin wound healing effect of a fibrin hydrogel scaffold loaded with hUC-MSCs. We found that the fibrin hydrogel had a three-dimensional mesh structure and low cytotoxicity and could prolong the time of cell survival in the peri-wound area. The number of green fluorescent protein (GFP)-labeled hUC-MSCs was higher in the full-thickness skin wound of mice treated with hydrogel-hUC-MSCs than those of mice treated with cell monotherapy. In addition, the combination therapy between the hydrogel and hUC-MSCs speed up wound closure, its wound healing rate was significantly higher than those of phosphate-buffered saline (PBS) therapy, hydrogel monotherapy, and hUC-MSCs monotherapy. Furthermore, the results showed that the combination therapy between hydrogel and hUCMSCs increased keratin 10 and keratin 14 immunofluorescence staining, and upregulated the relative gene expressions of epidermal growth factor (EGF), transforming growth factor-ß1 (TGF-ß1), and vascular endothelial growth factor A (VEGFA), promoting epithelial regeneration and angiogenesis. In conclusion, the fibrin hydrogel scaffold provides a relatively stable sterile environment for cell adhesion, proliferation, and migration, and prolongs cell survival at the wound site. The hydrogel-hUC-MSCs combination therapy promotes wound closure, re-epithelialization, and neovascularization. It exhibits a remarkable therapeutic effect, being more effective than the monotherapy with hUC-MSCs or hydrogel. [ABSTRACT FROM AUTHOR]