A
bstract
We analytically study phase transitions of holographic charged Rényi entropies in two gravitational systems dual to the
N
= 4 super-Yang-Mills theory at finite density and zero temperature. ...The first system is the Reissner-Nordström-AdS
5
black hole, which has finite entropy at zero temperature. The second system is a charged dilatonic black hole in AdS
5
, which has zero entropy at zero temperature. Hyperbolic black holes are employed to calculate the Rényi entropies with the entangling surface being a sphere. We perturb each system by a charged scalar field, and look for a zero mode signaling the instability of the extremal hyperbolic black hole. Zero modes as well as the leading order of the full retarded Green’s function are analytically solved for both systems, in contrast to previous studies in which only the IR (near horizon) instability was analytically treated.
•Coordinated calcium transport processes produce Ca2+ signatures in plant cells.•Magnesium transporters acquire and distribute Mg2+ throughout the plant.•CBL-CIPK signaling networks link calcium and ...magnesium homeostasis together.
Calcium (Ca2+) and magnesium (Mg2+) are the most abundant divalent cations in plants. As a nutrient and a signaling ion, Ca2+ levels in the cell are tightly controlled by an array of channels and carriers that provide mechanistic basis for Ca2+ homeostasis and the generation of Ca2+ signals. Although a family of CorA-type Mg2+ transporters plays a key role in controlling Mg2+ homeostasis in plants, more components are yet to be identified. Ca2+ and Mg2+ appear to have antagonistic interactions in plant cells, and therefore plants depend on a homeostatic balance between Ca2+ and Mg2+ for optimal growth and development. Maintenance of such a balance in response to changing nutrient status in the soil emerges as a critical feature of plant mineral nutrition. Studies have uncovered signaling mechanisms that perceive nutrient status as a signal and regulate transport activities as adaptive responses. This ‘nutrient sensing’ network is exemplified by the Ca2+-dependent CBL (calcineurin B-like)-CIPK (CBL-interacting protein kinase) pathway that serves as a major link between environmental nutrient status and transport activities. In this review, we analyze the recent literature on Ca2+ and Mg2+ transport systems and their regulation and provide our perspectives on future research.
Calcium (Ca2+) serves as an essential nutrient as well as a signaling agent in all eukaryotes. In plants, calcineurin B-like proteins (CBLs) are a unique group of Ca2+ sensors that decode Ca2+ ...signals by activating a family of plant-specific protein kinases known as CBL-interacting protein kinases (CIPKs). Interactions between CBLs and CIPKs constitute a signaling network that enables information integration and physiological coordination in response to a variety of extracellular cues such as nutrient deprivation and abiotic stresses. Studies in the past two decades have established a unified paradigm that illustrates the functions of CBL–CIPK complexes in controlling membrane transport through targeting transporters and channels in the plasma membrane and tonoplast.
A novel type of Ca2+ sensors, termed as calcineurin B-like proteins (CBLs), were identified in plant cells 20 years ago. They specifically target a family of plant-specific CBL-interacting protein kinases (CIPKs).To decode a Ca2+ signal, CBL binds Ca2+ and interacts with CIPK, leading to activation of the kinase. The CBL–CIPK complex phosphorylates downstream target proteins and changes their biological activities.Most CBL proteins are localized to the cell membranes and, as a result, CBL–CIPK complexes are largely associated with membranes. This unique feature underlies the core function of the CBL–CIPK network in regulating various membrane transport processes in the plasma membrane and the tonoplast, thereby linking Ca2+ signaling to plant nutrient sensing and homeostasis.
A new metal‐free radical 5‐exo‐dig cyclization of phenol‐linked 1,6‐enynes with O2, 2,2,6,6‐tetramethyl‐1‐piperidinyloxy (TEMPO), and tBuONO is described. With this general method, carbonylated ...benzofurans can be accessed through incorporation of two oxygen atoms into the product from O2 and TEMPO through dioxygen activation and oxidative cleavage of the NO bond, respectively.
Benzofurans are obtained by the tBuONO‐initiated radical 5‐exo‐dig cyclization of enynes under mild and metal‐free conditions. The two oxygen atoms that constitute the newly formed carbonyl groups of the benzofuran system originate from O2 and 2,2,6,6‐tetramethyl‐1‐piperidinyloxy (TEMPO), respectively.
State-owned private equity funds in China currently oversee assets worth more than 12 trillion RMB. Due to the uncertainty in the private equity market and the presence of information asymmetry, ...these state-owned private equity firms frequently engage in coinvestments with other private equity firms. The coinvestment strategy allows them to mitigate risks and exchange valuable information and resources. Which types of partners do state-owned private equity firms typically collaborate with? The existing literature built coinvestment partner selection models based on the traditional regression models and ignored the complexity of the network structure. This research analyzes cooperative relationships using exponential random graph models, considering both structural effects and node attributes. The empirical study of 4645 private equity firms operating in the Chinese private equity market shows that state-owned private equities are more likely to collaborate with foreign private equities and domestic private-owned private equities compared to collaborating with other state-owned private equities. Furthermore, in markets characterized by high marketization indexes, state-owned private equities demonstrate greater inclinations to partner with foreign and domestic private-owned private equities. When state-owned private equities allocate their investments to high-tech industries, their likelihood of collaborating with foreign private equities increases.
Sludge disposal is an integral part of wastewater treatment systems, and its cost usually accounts for more than half of the total operation cost. Sludge disposal technology is facing challenges and ...opportunities simultaneously and can still be improved. Sludge dewatering is an essential process in sludge disposal, and it is important for the effective reduction of the final processing cost. Coagulation/flocculation is a relatively mature, cost-effective, user-friendly sludge dewatering technology. In this work, coagulation/flocculation and their combinations with other pretreatments, including dewatering mechanisms, are reviewed. Various coagulants/flocculants used in sludge dewatering, including inorganic coagulants, organic synthetic and natural polymeric flocculants, and bioflocculants, are introduced in detail because coagulants/flocculants are the key in coagulation/flocculation. The different factors that influence the dewatering performance of these coagulants/flocculants are also presented briefly. Moreover, aiming at the complicated composition of sludge and its treatment difficulty, the prospects and technical developments of coagulation/flocculation in sludge dewatering are discussed.
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•Characteristics of different components in sludge and their detection methods.•External and internal factors of coagulation/flocculation on sludge dewatering.•Comparison and assessment of different coagulants/flocculants in sludge dewatering.•Combination of coagulation/flocculation with other techniques and their mechanisms.•Prospects and technical developments of coagulation/flocculation in sludge dewatering.
A chemical vapor deposition method is developed for thickness‐controlled (one to four layers), uniform, and continuous films of both defective gallium(II) sulfide (GaS): GaS0.87 and stoichiometric ...GaS. The unique degradation mechanism of GaS0.87 with X‐ray photoelectron spectroscopy and annular dark‐field scanning transmission electron microscopy is studied, and it is found that the poor stability and weak optical signal from GaS are strongly related to photo‐induced oxidation at defects. An enhanced stability of the stoichiometric GaS is demonstrated under laser and strong UV light, and by controlling defects in GaS, the photoresponse range can be changed from vis‐to‐UV to UV‐discriminating. The stoichiometric GaS is suitable for large‐scale, UV‐sensitive, high‐performance photodetector arrays for information encoding under large vis‐light noise, with short response time (<66 ms), excellent UV photoresponsivity (4.7 A W–1 for trilayer GaS), and 26‐times increase of signal‐to‐noise ratio compared with small‐bandgap 2D semiconductors. By comprehensive characterizations from atomic‐scale structures to large‐scale device performances in 2D semiconductors, the study provides insights into the role of defects, the importance of neglected material‐quality control, and how to enhance device performance, and both layer‐controlled defective GaS0.87 and stoichiometric GaS prove to be promising platforms for study of novel phenomena and new applications.
A chemical vapor deposition method is developed for controlling defects in gallium(II) sulfide (GaS), and their influence on the UV photosensing response in devices is elucidated. Defects in GaS act as sites of photoinduced oxidation and degradation. High‐quality GaS 2D films show uniform UV photodetector response and defect tuning enables selective UV sensing.
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