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The intracellular distribution and transportation process are essential for maintaining PD‐L1 (programmed death‐ligand 1) expression, and intervening in this cellular process may provide promising therapeutic strategies. Here, through a cell‐based high content screening, it is found that the ABCB1 (ATP binding cassette subfamily B member 1) modulator zosuquidar dramatically suppresses PD‐L1 expression by triggering its autophagic degradation. Mechanistically, ABCB1 interacts with PD‐L1 and impairs COP II‐mediated PD‐L1 transport from ER (endoplasmic reticulum) to Golgi apparatus. The treatment of zosuquidar enhances ABCB1‐PD‐L1 interaction and leads the ER retention of PD‐L1, which is subsequently degraded in the SQSTM1‐dependent selective autophagy pathway. In CT26 mouse model and a humanized xenograft mouse model, zosuquidar significantly suppresses tumor growth and accompanies by increased infiltration of cytotoxic T cells. In summary, this study indicates that ABCB1 serves as a negative regulator of PD‐L1, and zosuquidar may act as a potential immunotherapy agent by triggering PD‐L1 degradation in the early secretory pathway. [ABSTRACT FROM AUTHOR]

Circular RNAs (circRNAs) are implicated in the progression of breast cancer (BC). However, the explorations on circRNA IQ motif containing H (circIQCH) in BC progression remain limited. Functional experiments were conducted using in vitro and murine xenograft model assays, respectively. Dual‐luciferase reporter assay and RIP assay detected the associations among circIQCH, miR‐139‐5p, and nuclear factor IB (NFIB). CircIQCH was upregulated in BC, and the silencing of circIQCH repressed BC cell growth, metastasis, and autophagy, arrested cell cycle, promoted cell apoptosis in vitro, and blocked tumor growth in vivo. CircIQCH positively modulated NFIB expression by sponging miR‐139‐5p. Moreover, the deletion of miR‐139‐5p abated the action of circIQCH deficiency on BC cell malignant behaviors. Overexpression of miR‐139‐5p repressed the malignant characteristics of BC cells, while these impacts were abolished by elevating NFIB. Collectively, CircIQCH functioned as an oncogene in BC through upregulating NFIB expression by sponging miR‐139‐5p. [ABSTRACT FROM AUTHOR]

Organic semiconductors are promising candidates for next‐generation photodetectors owing to their unique properties including large absorption coefficient and intrinsic mechanical flexibility. However, limited by high defect density, large exciton binding energy, and short exciton diffusion length, many challenges remain for fabricating high‐performance organic photodetectors, especially for scenarios where weak light sensing and high‐speed imaging are required. Herein, by coupling single‐crystal pentacene with monolayer graphene, a vertical organic phototransistor with excellent zero‐bias photon detecting capacity is demonstrated. Under self‐powered weak light condition, the responsivity and specific detectivity are 2.86 AW−1 and 3.3 × 1011 Jones (based on experiment spectral noise density), respectively. It is demonstrated that weak light down to 25 nWcm−2 can be detected. When operating with an external bias, the responsivity of the device increases dramatically (up to 105 AW−1), and a better 3 dB bandwidth (≈74 kHz) is obtained. Finally, imaging functionality is demonstrated by employing this vertical transistor as a single‐sensing pixel. This work suggests organic single crystals exhibit enormous potential in advanced optoelectronic systems, and may provide a viable route for weak light detecting and high‐speed imaging. [ABSTRACT FROM AUTHOR]

The Poisson ridge estimator (PRE) is a commonly used parameter estimation method to address multicollinearity in Poisson regression (PR). However, PRE shrinks the parameters toward zero, contradicting the real association. In such cases, PRE tends to become an insufficient solution for multicollinearity. In this work, we proposed a new estimator called the Poisson average maximum likelihood‐centered penalized estimator (PAMLPE), which shrinks the parameters toward the weighted average of the maximum likelihood estimators. We conducted a simulation study and case study to compare PAMLPE with existing estimators in terms of mean squared error (MSE) and predictive mean squared error (PMSE). These results suggest that PAMLPE can obtain smaller MSE and PMSE (i.e., more accurate estimates) than the Poisson ridge estimator, Poisson Liu estimator, and Poisson K‐L estimator when the true β$$ \beta $$s have the same sign and small variation. Therefore, we recommend using PAMLPE to address multicollinearity in PR when the signs of the true β$$ \beta $$s are known to be identical in advance. [ABSTRACT FROM AUTHOR]

We examine how a CEO's family life affects their corporate decisions. Specifically, we investigate whether a CEO's spouse's professional status affects the CEO's risk‐taking behavior. Using a sample of S&P 500 firms from the 2010 to 2012 period, we find evidence that CEOs with spouses who are professionals, defined as working spouses, spouses holding graduate degrees, or spouses graduated from Ivy League schools, tend to adopt riskier corporate policies. Our evidence suggests that firms led by CEOs with professional spouses exhibit higher accounting return volatility, make more aggressive financial reporting decisions, and invest more in risky assets. We do not find a significant association between professional spouses and firms' market return volatility. Our results are consistent with the indirect channel theory, which suggests that CEOs with professional spouses might be inclined to undertake higher risks, potentially stemming from heightened conflicts between family and work commitments or improved wealth diversification attributed to their spouses' professional standing. [ABSTRACT FROM AUTHOR]

Freeze‐dried (FD) fruit and vegetable materials with a large amount of sugar are unstable. With the aim to understand the structure formation of FD products, the effects of fructose content on the texture and microstructure of FD matrix were investigated by using pectin–cellulose cryogel model. Cryogels containing fructose of 0–40% were produced using freeze‐drying at three different primary drying temperatures of −40, −20, and 20°C. The resultant cryogels were characterized by texture profile analyzer, scanning electron microscope, and μCT. Results indicated that at drying temperature of −40°C, increasing fructose concentration promoted the hardness of the cryogels, and cryogels of 16% fructose obtained maximum hardness. Excessive fructose (≥20%) weakened the described hardness, while exhibiting stronger springiness and resilience. The microstructure showed that dense pores and increased wall thickness due to fructose aggregation were critical factors responsible for increased hardness. The porous structure as well as relatively large pore size were necessary for crispness, in addition, rigid pore wall with certain strength were also required. At the drying temperature of 20°C, large hetero‐cavities dominated the microstructure of cryogels with 30% and 40% fructose, caused by melting inside during FD process. In this situation, lower Tm (−15.48 and −20.37°C) were responsible for cryogels' melting In conclusion, if possible, regulating fructose content and state may enable the precision texture design of FD fruit and vegetable foods. [ABSTRACT FROM AUTHOR]

Organic semiconductor crystals herald new opportunities for fabricating high‐performance optoelectronic devices, due to their intrinsic properties including outstanding charge transport properties, long exciton lifetime, and diffusion length. Despite remarkable progress in key figures of merit, the cut‐off frequency and responsivity are still lagging behind for most currently reported organic devices. Here, a high‐performance broadband vertical phototransistor based on rubrene single crystal, whose response covers the UV to visible range (300–650 nm) is reported. It shows a record‐high −3 dB bandwidth of ≈18 kHz and a maximum photoresponsivity of 105 A W−1. Due to the asymmetric Schottky contact and excellent light absorption of organic crystal, the device exhibits excellent zero‐bias photoresponse even under ultralow light illumination (≈114 fW). In particular, such organic vertical phototransistor holds good air stability and environmental robustness, and even without any form of encapsulation, no degradation of performance is observed for 2 months continuous operating. In addition, several single‐pixel imaging to show its potential for practical applications are demonstrated. The results provide a promising strategy to fabricate ultrafast and sensitive organic photodetectors for future video‐frame‐rate imaging. [ABSTRACT FROM AUTHOR]

Organic materials exhibit efficient light absorption and low‐temperature, large‐scale processability, and have stimulated enormous research efforts for next‐generation optoelectronics. While, high‐performance organic devices with fast speed and high responsivity still face intractable challenges, due to their intrinsic limitations including finite carrier mobility and high exciton binding energy. Here an ultrafast and highly sensitive broadband phototransistor is demonstrated by integrating high‐quality pentacene single crystal with monolayer graphene. Encouragingly, the −3 dB bandwidth can reach up to 26 kHz, which is a record‐speed for such sensitized organic phototransistors. Enormous absorption, long exciton diffusion length of pentacene crystal, and efficient interfacial charge transfer enable a high responsivity of >105 A W−1 and specific detectivity of >1011 Jones. Moreover, self‐powered weak‐light detection is realized using a simple asymmetric configuration, and the obvious zero‐bias photoresponses can be displayed even under 750 nW cm−2 light intensity. Excellent response speed and photoresponsivity enable high‐speed image sensor capability in UV‐Vis ranges. The results offer a practical strategy for constructing high‐performance self‐powered organic hybrid photodetectors, with strong applicability in wireless, weak‐light detection, and video‐frame‐rate imaging applications. [ABSTRACT FROM AUTHOR]

The production of hydrogen via electrochemical water splitting has the potential to enable the utilization of hydrogen‐powered fuel cells on a large scale. However, to realize this technology, inexpensive, noble metal‐free electrocatalysts possessing high performances for the hydrogen evolution reaction (HER) are needed. Mo2C nanoparticles recently receive much attention as alternative noble metal‐free electrocatalysts because their electronic structures are akin to that of Pt. However, the synthesis of Mo2C at nanoscale with high catalytic activity for HER remains a great challenge. Moreover, although efforts have been made to prevent their aggregation, the particles coalesce during high temperature carbonization, which is typically used to produce such transition metal carbides. Here, the synthesis of Mo2C nanodots that are well‐dispersed within 3D cage‐like carbon microparticles using rationally designed Mo‐based xerogels, which are prepared via the sol–gel process as precursors, is reported. During their pyrolysis, the xerogels maintain their structures while the Mo species in them transform into well‐dispersed Mo2C nanodots in situ. The as‐synthesized Mo2C nanodots exhibit excellent electrocatalytic activity for HER, in both alkaline and acidic media, while remaining largely stable. The work also demonstrates a promising synthetic route and procedure to other well‐dispersed yet stable nanocatalysts. [ABSTRACT FROM AUTHOR]

Molybdenum carbide possessing a Pt‐like d‐band electronic structure is considered as one of potential candidates of electrocatalysts and it shows intrinsic catalytic property. However, a high carbonizing temperature easily leads to the coalescence of nanoparticles (NPs). Here, we propose a simple sol‐gel route to achieve high dispersity of carbide NPs by designing a Mo‐involved xerogel. The results show that molybdenum carbide NPs are dispersed and anchored on the nitrogen‐doped carbon nanosheets (Mo2C@NC). Ultrathin carbon layers resemble graphene and the network structures act as a support of carbide NPs, which can hinder NPs' coalescence effectively. Nanpoparticles cross‐coupled on network‐structure nanosheets display the grid shapes. Electrochemical studies indicate that Mo2C@NC material exhibits outstanding hydrogen evolution performance in alkaline electrolyte. [ABSTRACT FROM AUTHOR]

This study proposed a GAN‐based reconstruction method‐cascaded data consistency generative adversarial network (CDCGAN) to recover high‐quality PET images from filtered back projection PET images with streaking artifacts and high noise. First, the authors embed defined data consistency layer (DC layer) in their generator network to constrain the reconstruction process and adjust accurately generated faked PET images. Second, to improve the accuracy of reconstruction on average, their generator network was built iteratively to achieve better performance with simple structures. They observed that the proposed CDCGAN allows the preservation of fine anomalous features while eliminating the streaking artifacts and noise. Experimental results show that the reconstructed PET images by their methods perform well comparably to other state‐of‐the‐art methods but at a faster speed. A clinical experiment was also performed to show the validity of the CDCGAN for artifacts reduction. [ABSTRACT FROM AUTHOR]

Positron emission tomography (PET) image reconstruction from low‐count projection data and physical effects is challenging because the inverse problem is ill‐posed and the resultant image is usually noisy. Recently, generative adversarial networks (GANs) have also shown their superior performance in many computer vision tasks and attracted growing interests in medical imaging. In this work, the authors proposed a novel model [deep residual generative adversarial network (DRGAN)] based on GANs for the reduction of streaking artefacts and the improvement of PET image quality. An innovative feature of the proposed method is that the authors trained a generator to produce 'residual PET map' (RPM) for image representation, rather than generate PET images directly. DRGAN used two discriminators (critics) to enforce anatomically realistic PET images and RPM. To better boost the contextual information, the authors designed residual dense connections followed with pixel shuffle operations (RDPS blocks) that encourage feature reuse and prevent losing resolution. Both simulation data and real clinical PET data are used to evaluate the proposed method. Compared with other state‐of‐the‐art methods, the quantification results show that DRGAN can achieve better performance in bias–variance trade‐off and provide comparable image quality. Their results were rigorously evaluated by one radiologist at the Shanxi Cancer Hospital. [ABSTRACT FROM AUTHOR]

Electrochemical water splitting has been considered as a promising method for large‐scale hydrogen production. However, the development of high‐performance and low‐cost noble metal‐free electrocatalysts for hydrogen evolution reaction (HER) remains a great challenge. Transition metal carbides (such as molybdenum carbide) are one of the most potential substitutes for noble metal as electrocatalysts for HER. One of the effective measures for further enhancing their performances is to hinder the coalescence of nanoparticles. Here we demonstrate a two‐dimensional ultrafine molybdenum carbide‐coupled mesoporous structured meshlike carbon nanolayers synthesized vis facile route based on holes in the carbon nanolayer structures blocking nanoparticle agglomeration. Molybdenum carbide clusters dispersed on the carbon nanolayers are successfully prepared by carbonization of molybdate‐polyvinylpyrrolidone precursor as a proof of concept, which exhibits excellent electrocatalytic activity for the HER and high stability in basic medium. The present study provides some references for the design and synthesis of nanostructured electrocatalysts utilizing 2D meshlike materials to prevent nanoparticles from agglomerating. [ABSTRACT FROM AUTHOR]

Transition metal carbide such as molybdenum carbide is most potential alternative to Pt catalysts for the hydrogen evolution reaction (HER). A high effective non‐noble metal electrocatalyst synthesized by the facile route isurgently needed. Herein, we designed a facile approach to synthesize molybdenum carbide nanocrystal dispersed on hexagonal carbon nanotablets possessing mesoporous structures. The electrocatalytic activities for HER were studied. The results show that as‐synthesized molybdenum carbide nanocomposites exhibit a superior HER activity and stability, with an overpotential of 176 mV to drive j=10 mA cm−2 in basic solution and a smaller Tafel slope of 52 mV dec−1in acidic medium, implying molybdenum carbide hexagonal nanotablets have a promising application as Pt‐free electrocatalysts for HER. This strategy also opens a new way to fast synthesize other non‐noble metal electrocatalysts for various applications. [ABSTRACT FROM AUTHOR]

The PPAR coactivator‐1α (PGC1α) is an important transcriptional co‐activator in control of fatty acid metabolism. Mitochondrial fatty acid oxidation (FAO) is the primary pathway for the degradation of fatty acids and promotes NADPH and ATP production. Our previous study demonstrated that upregulation of carnitine palmitoyl transferase 1 A (CPT1A), the key regulator of FAO, promotes radiation resistance of nasopharyngeal carcinoma (NPC). In this study, we found that high expression of PGC1α is associated with poor overall survival in NPC patients after radiation treatment. Targeting PGC1α could sensitize NPC cells to radiotherapy. Mechanically, PGC1α binds to CCAAT/enhancer binding protein β (CEBPB), a member of the transcription factor family of CEBP, to promote CPT1A transcription, resulting in activation of FAO. Our results revealed that the PGC1α/CEBPB/CPT1A/FAO signaling axis promotes radiation resistance of NPC. These findings indicate that the expression of PGC1α could be a prognostic indicator of NPC, and targeting FAO in NPC with high expression of PGC1α might improve the therapeutic efficacy of radiotherapy. [ABSTRACT FROM AUTHOR]

Carbonized Tree-Like Furry Magnolia Fruit-Based Evaporator Replicating the Feat of Plant Transpiration (Global Challenges 10/2019) Keywords: magnolia fruits; thermal management; tree-like evaporators; water purification Magnolia fruits, thermal management, tree-like evaporators, water purification, water purification. [Extracted from the article]

Given the global challenges of water scarcity, solar‐driven vapor generation has become a renewed topic as an energy‐efficient way for clean water production. Here, it is revealed that bamboo, as a natural hierarchical cellular material, can be an excellent 3D solar vapor‐generation device by a simple carbonization progress. A floating carbonized bamboo sample evaporates water with an extremely high vapor‐generation rate of 3.13 kg m−2 h−1 under 1 sun illumination. The high evaporation rate is achieved by the unique natural structure of bamboos. The inner wall of bamboo recovers the diffuse light energy and the thermal radiation heat loss from the 3D bamboo bottom, and the outer wall captures energy from the warmer environment. The high evaporation rate is also attributed to reduced vaporization enthalpy of water confined in the bamboo mesh. Such bamboo‐based high‐performance, low‐cost, self‐cleaning, solid durable, and scalable 3D vapor‐generation device has attractive applications in desalination as well as industrial and domestic wastewater abatement. [ABSTRACT FROM AUTHOR]