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Nitric oxide is one of the atmospheric pollutants and an important gas messenger molecule in the human body, involved in many physiological and pathological processes. Therefore, detecting nitric oxide rapidly and accurately has been one of the popular topics in recent decades. In this study, we synthesized CuCo-PTC MOF materials using a solvothermal method based on the mechanism of triazole ring formation from o-phenylenediamine (OPD) and nitric oxide. The synthesized CuCo-PTC MOF materials show high sensitivity and good selectivity for detecting nitric oxide in vitro and in cell lysates. The results indicate the potential for applying this sensing strategy to detect nitric oxide in the internal environment.

Aluminum gallium nitride (AlGaN) high electron mobility transistors (HEMTs) are candidates for next-generation power conversion and radio frequency (RF) applications. AlxGa1-xN channel HEMT devices (x = 0.3, x = 0.7) were investigated using multiple in-situ thermal characterization methods and electro-thermal simulation. The thermal conductivity, contact resistivity, and channel mobility were characterized as a function of temperature to understand and compare the heat generation profile and electro-thermal transport within these devices. In contrast to GaN-based HEMTs, the electrical output characteristics of Al0.70Ga0.30 N channel HEMTs exhibit remarkably lower sensitivity to the ambient temperature rise. Also, during 10kHz pulsed operation, the difference in peak temperature between the AlGaN channel HEMTs and GaN HEMTs reduced significantly.

Rationale: CD47 plays a vital role in the immune escape of tumor cells, but its role in regulating immune-unrelated biological processes such as proliferation and metastasis remains unclear. We seek to explore the immune-independent functions of CD47 in colorectal cancer (CRC). Methods: The expression of CD47 in CRC was determined by immunohistochemistry. The biological effect of CD47 signaling on tumor cell proliferation and metastasis was evaluated in vitro and in vivo. RNA sequencing analysis was performed to identify pivotal signaling pathways modulated by CD47. The interaction between CD47 and ENO1 was verified by co-immunoprecipitation (co-IP). The effect of CD47 on glycolytic metabolites was analyzed by seahorse XF and targeted metabolomics. Results: The expression of CD47 was upregulated and correlated to poor prognosis in CRC patients. Functional assays revealed that CD47 promoted CRC cell growth and metastasis in vitro and in vivo. Our mechanistic investigations demonstrated that CD47 interacted with ENO1 and protected it from ubiquitin-mediated degradation, subsequently promoting glycolytic activity and phosphorylation of ERK in CRC cells. Inhibition of ENO1 diminished CD47-mediated cell growth and migration. Clinically, the combined expression of CD47 and ENO1 provided reliable predictive biomarkers for the prognosis of CRC patients. Conclusions: CD47 is overexpressed in CRC, and its expression is associated with poor prognosis. Through stabilizing ENO1, CD47 enhances the aerobic glycolysis and ERK activity in CRC cells, thereby promoting the progression of CRC. Our studies reveal an unconventional role of CD47, suggesting that targeting the CD47-ENO1 axis may provide a novel therapeutic avenue for CRC.

AlN thin films are enabling significant progress in modern optoelectronics, power electronics, and microelectromechanical systems. The various AlN growth methods and conditions lead to different film microstructures. In this report, phonon scattering mechanisms that impact the cross-plane (κz; along the c-axis) and in-plane (κr; parallel to the c-plane) thermal conductivities of AlN thin films prepared by various synthesis techniques are investigated. In contrast to bulk single crystal AlN with an isotropic thermal conductivity of ∼330 W/m K, a strong anisotropy in the thermal conductivity is observed in the thin films. The κz shows a strong film thickness dependence due to phonon-boundary scattering. Electron microscopy reveals the presence of grain boundaries and dislocations that limit the κr. For instance, oriented films prepared by reactive sputtering possess lateral crystalline grain sizes ranging from 20 to 40 nm that significantly lower the κr to ∼30 W/m K. Simulation results suggest that the self-heating in AlN film bulk acoustic resonators can significantly impact the power handling capability of RF filters. A device employing an oriented film as the active piezoelectric layer shows an ∼2.5× higher device peak temperature as compared to a device based on an epitaxial film.

β-phase gallium oxide (Ga

Heteroepitaxy of β-phase gallium oxide (β-Ga

Water scarcity forms a risk to sustainable development in arid and semi-arid areas. Fog harvesting is a sustainable source for drinking water because of its passive collection, minimal energy requirement, and low maintenance cost. Creatures living in desert areas can survive well because they can extract water directly from the atmosphere usually owing to their hierarchical micro- and nanostructures. Bioinspired structures used to harvest fog have drawn immense attention in recent years. Various bioinspired surfaces for water harvesting are reviewed including plants (cactus, lotus, rice, pitaya, Cotula fallax, Eremopyrum orientale, Salsola crassa, and Gladiolus dalenii) and animals (Stenocara Beetle, spider silk, lizard, cicada wing, earthworms, caterpillars, and mussels) from the aspects of fabrication processes and water collecting efficiency. A comparison table is given with the maximum water collecting efficiency 5300 mg/(cm2 h). Water transportation and collection are also briefly discussed. Inspiration from nature is just a starting point. The ultimate goal is to increase both the efficiency and the amount of fog harvesting in order to practical usage.

Canine mammary cancer is poorly characterized at the genomic level. Dog really can be an appropriate experimental model for human cancers from the genomic and evolutionary perspective or not? Here, we perform a cross-species cancer genomics analysis, independent evolution of cancer from normal tissues, which provide us an excellent opportunity to address an evolutionary perspective of cancer. As, evolutionary theories are critical for understanding tumorigenesis at the level of species as well as at the level of cells and tissues, for the development of effective therapies. Analysis of canine mammary cancer reveals a diversity of histological types as compare to human breast cancer. Our systematic analysis of 24 canine mammary tumors with whole-genome sequences, reveals 185 protein-coding cancer genes carried exonic mutations. Cross-species comparative analysis of 1080 human breast cancers identifies higher median mutation frequency in human breast cancer and canine mammary cancer shows lower across exonic regions (2.67 and 0.187 average no. of mutations per tumor per megabase (Mb), respectively). A comparison of somatic mutations in the PIK3CA gene, reveals common recurrence of the conserved mutations, in both species. However, the Ka/Ks ratio in the human PIK3CA gene 2.37 is higher and 1.43 in dogs is lower. To address the mutation accumulation and antagonistic pleiotropy theory, we investigated Ka/Ks value 237 aging-related genes from human and canine, the aging-related genes do not show selection in canine mammary cancer. It demonstrates new aspects of cancer genes that are evolving in different species instantaneously. These findings may suggest, the same organs in different mammals impose different selective pressures on the same set of genes in cancer. In both species, some genes may experience strong selective pressures, but do not converge genetically or the conserved genes do not show the same selection pressure in both species. However, human breast cancer shows transcriptomic similarity with canine mammary carcinoma but the other subtypes are quite different. We found canine mammary tumor can be used as a model for inter and intra-tumor heterogeneity. These findings provided insight into mammary cancer across species and possessed potential clinical significance. Collectively, these studies suggest a convergence of some genetic changes in mammary cancer between species but also distinctly different paths to tumorigenesis.

Gallium nitride (GaN) has emerged as one of the most attractive base materials for next-generation high-power and high-frequency electronic devices. Recent efforts have focused on realizing vertical power device structures such as in situ oxide, GaN interlayer based vertical trench metal–oxide–semiconductor field-effect transistors (OG-FETs). Unfortunately, the higher-power density of GaN electronics inevitably leads to considerable device self-heating which impacts device performance and reliability. Halide vapor-phase epitaxy (HVPE) is currently the most common approach for manufacturing commercial GaN substrates used to build vertical GaN transistors. Vertical device structures consist of GaN layers of diverse doping levels. Hence, it is of crucial importance to measure and understand how the dopant type (Si, Fe, and Mg), doping level, and crystal quality alter the thermal conductivity of HVPE-grown bulk GaN. In this work, a steady-state thermoreflectance (SSTR) technique was used to measure the thermal conductivity of HVPE-grown GaN substrates employing different doping schemes and levels. Structural and electrical characterization methods including X-ray diffraction (XRD), secondary-ion mass spectrometry (SIMS), Raman spectroscopy, and Hall-effect measurements were used to determine and compare the GaN crystal quality, dislocation density, doping level, and carrier concentration. Using this comprehensive suite of characterization methods, the interrelation among structural/electrical parameters and the thermal conductivity of bulk GaN substrates was investigated. While doping is evidenced to reduce the GaN thermal conductivity, the highest thermal conductivity (201 W/mK) is observed in a heavily Si-doped (1–5.00 × 1018 cm−3) substrate with the highest crystalline quality. This suggests that phonon-dislocation scattering dominates over phonon-impurity scattering in the tested HVPE-grown bulk GaN substrates. The results provide useful information for designing thermal management solutions for vertical GaN power electronic devices.

The β-gallium oxide (Ga 2 O 3 ) material system offers the potential to dramatically improve the electrical performance and cost-effectiveness of next-generation power electronics. This is because of its ultra-wide bandgap (~4.8 eV) and the availability of high-quality single-crystal bulk substrates. However, the low thermal conductivity of Ga 2 O 3 (11-27 W/m-K) implies that significant thermal challenges need to be overcome to commercialize Ga 2 O 3 devices. In the present work, a single crystal (010) Ga 2 O 3 wafer was integrated with a 4H-SiC substrate via fusion bonding to address this concern of poor thermal conductivity. A differential steady-state thermoreflectance method was established to measure the thermal boundary resistance at the Ga 2 O 3 /SiC interface (100 m2K/GW), which has yet to be reported due to the limited probing depth of conventional frequency- and time-domain thermoreflectance techniques.

Under the background of ecological civilization construction, this article aims at the Qingdao Shooting Sports Center project, with the specific technical scheme, and energy consumption calculation adopted in green construction and energy saving. Combining the theoretical knowledge of green buildings with actual projects, through the energy-saving assessment of the project, the type and quantity of energy consumption of the project are grasped, the energy consumption level of the project is analyzed, and the rationality of the energy utilization of the project and the feasibility of energy-saving measures are evaluated. This article provides some reference data and research for preparing the green and energy-saving design and evaluation report of public building projects.

In recent years, with the rapid development of economy, science and technology in China, computer music technology has been gradually applied to the teaching of public music in the information age. In the process of music teaching, computer music technology can enhance the interest and flexibility of solfeggio, harmony and other theoretical courses, but also shorten the distance between music theory and practice, thus arousing students' interest in learning music, and then greatly optimizing the teaching effect and music teaching idea of music theory course in colleges and universities. By studying the status of computer music application in public music class, this paper analyzes the effect of computer music on public music class, to promote the teaching effect of public music class.

Researchers have been extensively studying wide-bandgap (WBG) semiconductor materials such as gallium nitride (GaN) with an aim to accomplish an improvement in size, weight, and power (SWaP) of power electronics beyond current devices based on silicon (Si). However, the increased operating power densities and reduced areal footprints of WBG device technologies result in significant levels of self-heating that can ultimately restrict device operation through performance degradation, reliability issues, and failure. Typically, self-heating in WBG devices is studied using a single measurement technique while operating the device under steady-state direct current (DC) measurement conditions. However, for switching applications, this steady-state thermal characterization may lose significance since high power dissipation occurs during fast transient switching events. Therefore, it can be useful to probe the WBG devices under transient measurement conditions in order to better understand the thermal dynamics of these systems in practical applications. In this work, the transient thermal dynamics of an AlGaN/GaN high electron mobility transistor (HEMT) were studied using thermoreflectance thermal imaging and Raman thermometry. Also, the proper use of iterative pulsed measurement schemes such as thermoreflectance thermal imaging to determine the steady-state operating temperature of devices is discussed. These studies are followed with subsequent transient thermal characterization to accurately probe the self-heating from steady-state down to sub-microsecond pulse conditions using both thermoreflectance thermal imaging and Raman thermometry with temporal resolutions down to 15 ns.

The extremely high concentration of the electric field near the drain corner of the gate is the major cause for premature breakdown and local hotspot formation of AlGaN/GaN high electron mobility transistors (HEMTs). This hotspot negatively impacts the device performance, reliability, lifetime, and limits the operability envelope. Metal field plates have been used to mitigate this electric field concentration. However, it has been proven difficult to reach the theoretical breakdown voltage of GaN using conventional field plate structures. In this work, a novel “resistive field plate” structure based on amorphous indium-gallium-zinc-oxide (a-IGZO) was constructed to minimize the electric field concentration by imposing a linear voltage boundary condition on the device surface, between the drain and source electrodes. Standard electrical testing and state-of-the-art optical thermography techniques were used to understand the electro-thermal interactions behind the improvement in electrical and thermal performance of AlGaN/GaN metal-oxide-semiconductor HEMTs (MOS-HEMTs) employing the a-IGZO resistive field plate. The novel field plated design resulted in ∼25% increase in the device breakdown voltage (V B ) and ∼24% reduction in the channel peak temperature as compared to a control sample employing no field plate structures. Key knowledge obtained from this study provides insight into enhancing the performance and reliability of AlGaN/GaN HEMTs and also suggests a viable solution that may enable the full exploitation of the potential of wide bandgap and ultra-wide bandgap lateral power electronic devices.

In this study, the Raman biaxial stress coefficients KII and strain-free phonon frequencies ω0 have been determined for the E2 (low), E2 (high), and A1 (LO) phonon modes of aluminum nitride, AlN, using both experimental and theoretical approaches. The E2 (high) mode of AlN is recommended for the residual stress analysis of AlN due to its high sensitivity and the largest signal-to-noise ratio among the studied modes. The E2 (high) Raman biaxial stress coefficient of −3.8 cm−1/GPa and strain-free phonon frequency of 656.68 cm−1 were then applied to perform both macroscopic and microscopic stress mappings. For macroscopic stress evaluation, the spatial variation of residual stress was measured across an AlN-on-Si wafer prepared by sputter deposition. A cross-wafer variation in residual stress of ∼150 MPa was observed regardless of the average stress state of the film. Microscopic stress evaluation was performed on AlN piezoelectric micromachined ultrasonic transducers (pMUTs) with submicrometer spatial resolution. These measurements were used to assess the effect of device fabrication on residual stress distribution in an individual pMUT and the effect of residual stress on the resonance frequency. At ∼20 μm directly outside the outer edge of the pMUT electrode, a large lateral spatial variation in residual stress of ∼100 MPa was measured, highlighting the impact of metallization structures on residual stress in the AlN film.

Floquet topological insulators (FTIs) have been used to study the topological features of a dynamic quantum system within the band structure. However, it is difficult to directly observe the dynamic modulation of band structures in FTIs. Here, we implement the dynamic Su–Schrieffer–Heeger model in periodically curved waveguides to explore new behaviors in FTIs using light field evolutions. Changing the driving frequency produces near-field evolutions of light in the high-frequency curved waveguide array that are equivalent to the behaviors in straight arrays. Furthermore, at modest driving frequencies, the field evolutions in the system show boundary propagation, which are related to topological edge modes. Finally, we believe curved waveguides enable profound possibilities for the further development of Floquet engineering in periodically driven systems, which ranges from condensed matter physics to photonics.

The motion of domain walls in lead zirconate titanate (PZT) produces both nonlinearity and hysteresis. While measurements of the resulting self-heating under an electric field drive are well known in bulk ferroelectric ceramics, self-heating effects in PZT films may differ from those in bulk ceramics due to a combination of reduced domain wall motion, differences in heat dissipation associated with substrates or passive elastic layers, and differences in typical drive fields. Here, it is shown that the thermal imaging of the test structures of PZT piezoelectric microelectromechanical systems using techniques such as infrared thermography and thermoreflectance thermal imaging suffers from motion-induced artifacts. These limitations were overcome via nanoparticle-assisted Raman thermometry with a spatial resolution of ∼1 μm. To acquire the local temperature distribution quantitatively, anatase nanoparticles were distributed across the electrodes and actuating PZT diaphragm. The temperature rise of the test structures increased as the operating frequency, voltage amplitude, and slew rate increased. As expected, the largest temperature rises were induced due to self-heating associated with domain switching under bipolar operation. In addition, a higher voltage amplitude testing revealed non-uniform temperature distributions across the piezoelectric actuator, suggesting that AC Joule heating can induce significant heat generation (ΔT ∼ 30 K) under high electric fields (∼390 kV/cm).

Ultra-wide bandgap β-gallium oxide (Ga2O3) devices are of considerable interest with potential applications in both power electronics and radio frequency devices. However, current Ga2O3 device technologies are limited by the material's low intrinsic electron mobility and thermal conductivity. The former problem can be addressed by employing modulation-doped β-(AlxGa1−x)2O3/Ga2O3 heterostructures in the device architecture. In this work, (AlxGa1−x)2O3/Ga2O3 modulation-doped field effect transistors (MODFETs) have been investigated from a thermal perspective. Thermoreflectance thermal imaging was used to characterize the self-heating of the MODFETs. The (Al0.18Ga0.82)2O3 thermal conductivity (3.1–3.6 W/mK) was determined using a frequency domain thermoreflectance technique. Electro-thermal modeling was used to discern the effect of design parameters such as substrate orientation and channel length on the device self-heating behavior. Various thermal management schemes were evaluated using the electro-thermal device model. From an electro-thermal co-design perspective, the improvement in electrical performance followed by the mitigation of self-heating was also studied. For example, by employing a Ga2O3-on-SiC composite wafer, which was fabricated in this work, a 50% increase in power handling capability can be achieved as compared to a homoepitaxial device. Furthermore, flip-chip heterointegration and double-sided cooling approaches can lead to more than 2× improvement in the power handling capability. Using an augmented double-sided cooling design that includes nanocrystalline diamond passivation, a 5× improvement in the power handling capability can be accomplished, indicating the potential of the technology upon implementation of a suitable thermal management scheme.

Improvements in radio frequency and power electronics can potentially be realized with ultrawide bandgap materials such as aluminum gallium nitride (AlxGa1−xN). Multidimensional thermal characterization of an Al0.30Ga0.70N channel high electron mobility transistor (HEMT) was done using Raman spectroscopy and thermoreflectance thermal imaging to experimentally determine the lateral and vertical steady-state operating temperature profiles. An electrothermal model of the Al0.30Ga0.70N channel HEMT was developed to validate the experimental results and investigate potential device-level thermal management. While the low thermal conductivity of this III-N ternary alloy system results in more device self-heating at room temperature, the temperature insensitive thermal and electrical output characteristics of AlxGa1−xN may open the door for extreme temperature applications.

Hematopoietic stem and progenitor cell (HSPC) functions are governed by intricate signaling networks. The tyrosine kinase JAK2 plays an essential role in cytokine signaling during hematopoiesis. The adaptor protein LNK is a critical determinant of this process through its inhibitory interaction with JAK2, thereby limiting HSPC self-renewal. LNK deficiency promotes myeloproliferative neoplasm (MPN) development in mice, and LNK loss-of-function mutations are found in human MPNs, emphasizing its pivotal role in normal and malignant HSPCs. Here, we report the identification of 14-3-3 proteins as LNK binding partners. 14-3-3 interfered with the LNK-JAK2 interaction, thereby alleviating LNK inhibition of JAK2 signaling and cell proliferation. Binding of 14-3-3 required 2 previously unappreciated serine phosphorylation sites in LNK, and we found that their phosphorylation is mediated by glycogen synthase kinase 3 and PKA kinases. Mutations of these residues abrogated the interaction and augmented the growth inhibitory function of LNK. Conversely, forced 14-3-3 binding constrained LNK function. Furthermore, interaction with 14-3-3 sequestered LNK in the cytoplasm away from the plasma membrane-proximal JAK2. Importantly, bone marrow transplantation studies revealed an essential role for 14-3-3 in HSPC reconstitution that can be partially mitigated by LNK deficiency. We believe that, together, this work implicates 14-3-3 proteins as novel and positive HSPC regulators by impinging on the LNK/JAK2 pathway.

Ever since the appearance of woodblock printing in Yangzhou during the Tang Dynasty, the development of Yangzhou woodcut prints has been rapid in Song, Yuan and Ming dynasties, which flourished in the Qing Dynasty. Compared with the previous dynasties, the printing industry of Yangzhou woodcut prints in the Qing Dynasty has more variety a larger scale. As people begin to attach more attention to the artistic value of Yangzhou woodcut prints, therefore this paper carried out an analysis and research on Yangzhou woodcut prints in the Qing Dynasty. Yangzhou has been an important cultural and economic town in Ming and Qing dynasties due to its location at the junction of canal and the Yangtze River. With continuous development of Yangzhou woodcut prints printing technology in the Qing Dynasty, Yangzhou woodcut prints also made a very outstanding achievement, forming a very important part of the history of ancient woodcut prints in China. Yangzhou woodblock printing was renowned throughout the country at that time, the current offset printing in Yangzhou has quite a lot of workshop printing, family printing and official printing copies, on account of its high artistic achievement, it also ranks top in the famous engraving books in our country. Yangzhou is one of the center cities of woodblock printing in Ming and Qing dynasties, also the only city reserving the full range of ancient China's woodblock printing technology. Currently, Yangzhou roughly has a collection of three hundred thousand ancient book copies of Ming and Qing dynasties, in which there are many exquisite woodcut prints. The earliest Yangzhou woodcut prints had a comparatively unique style and remaining quantity, with a relatively distinct artistic style and characteristics, which are possible to well reflect indigenous aesthetic taste.

Abstract 86 Hematopoietic stem and progenitor cell (HSPC) homeostasis is regulated by intricate signaling networks. The tyrosine kinase JAK2 plays an essential role in cytokine signaling during hematopoiesis and its dysregulation can lead to hematologic malignancies. Recently activating mutations in JAK2 were found in a large fraction of patients with myeloproliferative neoplasms (MPNs). We previously demonstrated that lymphocyte adaptor protein (Lnk) binds JAK2 and attenuates its activity, thereby limiting HSPC expansion (Bersenev et al., JCI, 2008;118:2832-2844). We further showed that loss of Lnk accelerates and exacerbates oncogenic JAK2-induced MPNs in mice (Bersenev et al., JCI, 2010;120:2058-2069). Lnk directly inhibits oncogenic JAK2 as well as acting through JAK2- independent pathways to constrain MPN development. Consistently, aged Lnk–/– mice spontaneously developed a CML-like MPN (Bersenev et al., JCI, 2010;120:2058-2069). More importantly, loss-of-function mutations in Lnk are found in human MPN patients (Oh, et. al., Blood, 2010, in press). This work suggests that Lnk plays a pivotal role in regulating both normal and malignant HSPC expansion. However, it remains to be determined how Lnk attenuates JAK2 activity since Lnk itself does not possess any enzymatic activity. Therefore, we began exploring Lnk regulatory mechanisms by identifying novel Lnk partners through protein purification and mass spectrometric analysis. This resulted in the identification of a number of novel Lnk binding proteins, which include the 14-3-3 proteins as the most robust interactors. 14-3-3s are a group of scaffold proteins that regulate many disease-relevant gene products and play important functions in many aspects of cellular processes. We found that Lnk is phosphorylated at two serine residues, which serve as the critical binding sites for 14-3-3. 14-3-3 abrogates the Lnk-JAK2 interaction thereby alleviating Lnk inhibitory function in both JAK2 signaling and cell growth. Furthermore, 14-3-3 binding is necessary and sufficient to maintain Lnk in an inactive state. We also investigated the signals that regulate Lnk phosphorylation, revealing Lnk as a signaling nodal point that integrates multiple signaling pathways in controlling HSPC homeostasis. The physiological significance of the Lnk-14-3-3 interaction in HSPC development will be discussed. Thus, our data implicate previously unappreciated serine phosphorylation events in Lnk-dependent hematopoietic function and regulation of JAK2. In addition, identification of novel signaling molecules that influence hematopoiesis might facilitate stem cell therapies and provide novel therapeutic targets for the treatment of MPNs. Disclosures: No relevant conflicts of interest to declare.