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Subcellular organelle-targeted photosensitizers have recently reported to be effective photodynamic therapy (PDT) agents. In this work, three porphyrin-derived photosensitizers, containing one, two or four triphenylphosphonium targeting groups, were synthesized and characterized by NMR, HRMS, UV-vis and fluorescence spectroscopy. These photosensitizers showed similar photophysical properties to classical porphyrins and exhibited excellent [Formula: see text]O[Formula: see text] quantum yields in acetonitrile. Subcellular colocalization indicated that all three photosensitizers specifically stain the mitochondria of HeLa cells. Photosensitizer mito-dp, containing two triphenylphosphonium cations was found to be the most uptaken by cells and exhibited the best PDT effect with an effective phototoxicity (IC[Formula: see text] (light) [Formula: see text] 12.4 nM), suggestive of a higher practicable potential of mitochondria-targeted PDT agents in cancer therapy.

Bayberry is an important fruit tree native to the subtropical regions of China. However, a systematic twig blight disease caused by Pestalotiopsis versicolor and P. microspora, resulted in the death of the whole tree of bayberry. The main variety Dongkui is highly sensitive to the twig blight disease, but the variety Zaojia is very highly resistant to the disease. Therefore, it is very necessary to clear the difference between resistant and susceptible varieties in response to the fungal infection. In this paper, we investigated the response of resistant and susceptible bayberry cultivars to infection of twig blight pathogen by histological observation and gibberellin signaling pathway-related genes expression. Microscopic observation revealed the difference in the infection process between resistant and susceptible varieties. The results of frozen scanning electron microscopy showed that the Pestalotiopsis conidia were shrunk, the mycelium was shriveled and did not extend into the cells of resistant cultivars, while the conidia were full and the top was extended, the mycelia was normal and continued to extend to the cells of a susceptible cultivar. Indeed, the medulla cells were almost intact in resistant cultivar, but obviously damaged in susceptible cultivar after inoculation of the main fungal pathogen P. versicolor conidia, which is earlier germinated on sterile glass slide than that of a hard plastic slide. The quantitative real-time PCR results showed a significant difference between resistant and susceptible cultivars in the expression of gibberellin signaling pathway-related genes in leaves and stems of bayberry, which is closely related to infection time, the type of genes and varieties. Overall, this study provides a clue for our understanding of the resistance mechanism of bayberry against the twig blight disease.

A new reaction-based, colorimetric fluorescent sensor of BODIPY derivative ( 1 ) for cysteine (Cys) has been designd and synthesized. This probe shows highly selective detection of Cys over homocysteine (Hcy), glutathione (GSH) as well as other amino acids with a dramatic color change from wine red to fluorescence green because of the significant increase of the visible light excitable fluorescence intensity with the addition of Cys, due to their different reaction rates of the Michael addition reaction. The detection limit for Cys was 8.57 × 10 −7 M. Possible mechanism for sensing of Cys by BODIPY 1 was studied by NMR and HRMS. Probe 1 has been successfully applied to the biological imaging of Cys in living cells.

In the shale gas extraction, drilling and hydrofracturing bring large amounts of water-based working fluid into shale reservoirs, which much affects the wellbore stability and gas production rate. To investigate the effect of water-based working fluid imbibition on static and dynamic compressive properties of anisotropic shale, the INSTRONG 1346 electro-hydraulic servo system and a modified Split Hopkinson pressure bar test system were used to perform the static and dynamic compressive tests on the dry and water-saturated shale specimens with bedding plane inclinations of 0°, 30°, 45°, 60° and 90°. Results reveal that the water imbibition process can be divided into three stages, and the chemical water-shale interaction may occur at the second stage. Under static and dynamic compressive loading, water imbibition can seriously weaken the strength and elastic modulus of specimens with the five different bedding plane inclinations, but increase the failure strain. Under the two loading forms, the relationship between compressive parameters of water-saturated specimens and the bedding plane inclination shows the same evolution trend as that of dry specimens, and the compressive parameters are affected the greatest by water imbibition when the bedding plane inclination is 45° or 60°. Furthermore, the mechanism of strength deterioration and the quantitative evaluation on anisotropy of dry and water-saturated specimens under the static and dynamic compressive tests are analyzed and discussed.

The number of cells in tissues is under strict genetic control, and research on the determination of cell number is of great importance to understand the growth and development of organs. Bmsage, a bHLH transcription factor, is involved in the development of the silk gland during the embryonic stage in Bombyx mori. However, the mechanism by which it influences silk gland development is unclear. In the present study, we determined via immunofluorescence staining during the embryonic stage of Bombyx mori that Bmsage is expressed in silk gland cells from the beginning of development of the silk gland until its complete formation. By comparing different silkworm strains, we found that Bmsage expression is positively correlated with the number of silk gland cells. Bmsage knockdown by RNAi resulted in shorter silk glands and lower cell numbers, especially in the posterior silk gland. The silk gland lumen also shriveled, and the silk protein content was significantly lower than that in the control. Further investigation revealed that all cyclins decreased after knock down of Bmsage, and cyclin B and cyclin 3 were significantly down-regulated. Bmsage may be involved in the regulation of the cyclin pathway to control silk gland development. Taken together, it can be concluded from our results that Bmsage is involved in the determination of cell number in silk glands. Our results help clarify the process of cell number determination in silk gland and identify a potential target for silkworm breeding.

By taking advantage of “turn off” or “turn on” fluorescence of visible light excitable BODIPYs, a selective fluorescent and colorimetric “naked eye” sensing of cysteine (Cys) and/or homocysteine (Hcy) in methanol-HEPES buffer (45 mM, pH = 7.2, v/v = 1/1) solution over various common amino acids and related thiol-containing compounds has been achieved based on the reaction of the formyl groups on α- and β-formyl BODIPYs 1 and 3 with Cys/Hcy. β-FormylBODIPY 1 showed a selective response for both Cys and Hcy over the other analytes, with an apparent color change from green to light brown due to a dramatic quenching of the fluorescence intensity. In contrast, α-formylBODIPY 3 gave “naked eye” discrimination between Cys and Hcy, with a dramatic color change from light orange to yellowish green because of a significant increase of the green fluorescence intensity with the addition of Cys. The possible mechanism for sensing of Cys and/or Hcy by BODIPYs 1 and 3 was studied by NMR, HRMS and DFT calculations. α-FormylBODIPY 3 has been applied to the biological imaging of Cys in living cells.

Selective fluorescent and colorimetric sensing of cysteine in methanol-HEPES buffer (45 mM, pH [Formula: see text] 7.2, v/v [Formula: see text] 1/1) solution over various common amino acids and related thiol containing compounds has been achieved based on the cyclization reaction between the formyl group on 3-formylBODIPYs and cysteine/homocystein. Upon addition of cysteine/homocystein, 3-formylBODIPYs exhibited greatly enhanced fluorescence intensity as well as an abvious red-shift of the absorption peak (20–30 nm). The detection limits for cysteine were in the range of 1.18–2.73 [Formula: see text]10[Formula: see text] M. The detection mechanism was studied by nuclear magnetic resonance and theoretical calculation.

The key technology issue in deep hole drilling of hot dry rock (HDR) for geothermal energy exploitation is the stability of the surrounding rock. The temperature and in situ stress of the borehole play a significant role in its deformation and instability under high-pressure and high-temperature conditions. Based on the occurrence conditions of the granite reservoir of the Yangbajing geothermal field in Tibet, a research was conducted by means of experimental study, numerical simulation, and theoretical analysis, from which the following conclusions were drawn. (1) The deformation and failure laws of borehole are based on the physical experiment on granite specimen under high-temperature and high-pressure conditions. (2) The Weibull distribution of the thermal expansion coefficient is used for establishing rock heterogeneity, and the COMSOL software is used to reproduce the temperature and stress distribution of the borehole during physical experiment, thus demonstrating the distribution of the temperature field, stress field, and displacement field under thermo-mechanical coupling (TMC) condition. (3) Based on the complete analysis of the temperature field and stress field, combined with the conclusions of the deformation and failure of granite specimen under high-temperature and high-pressure conditions, the failure laws of borehole under the TMC condition were analyzed, as well as the critical conditions of borehole instability during deep hole drilling of HDR. (4) With the critical conditions of borehole instability during deep hole drilling of HDR, which the relation between the in situ stress σ and temperature T is σ = 241.9–0.3998 T. These conclusions have practical guiding significance to the stability control of the surrounding rocks of borehole in relation to projects such as geothermal energy exploitation from HDR, deep oil and gas resource extraction, and deep hole drilling in mainland China.

50 MW heat release rate fire is the most representative in tunnel fire. The paper has a systematic study on the temperature distribution and thermal damage of the maximum temperature section with a heat release of 50 MW by means of theoretical analysis, numerical simulation and experimental investigations. Research results show that with the increase of ventilation velocity, the maximum temperature point of tunnel lining distributes within the range of 5 m of the upper and lower reaches of the fire source. The surface temperature of cross section lining lies in the maximum temperature section showing a continuous decrease trend from the vault to the side wall. The threshold temperature value of strength damage is 400 °C when the fire temperature lowers than 700 °C. The heat causes serious damage in the tunnel vault for concrete lining with a thickness of 35 cm whose heat damage could be 9.80 cm. Also, the damage region distributes within the range of 5 m of the upper and lower reaches of the fire source and shows a continuous decrease trend from the vault to the side wall. The results can provide reference for the stability and safety assessment of tunnel lining and the repair of tunnel lining damage after fire.

The Internet reserves numerous potential path diversity among densely connected autonomous systems (ASes). However, the Internet routing is controlled by Border Gateway Protocol (BGP), which has limitations in the path diversity expression and cooperation between ASes. The emergence of software defined networking (SDN) scheme provides flexible control over networks. In this paper, we leverage the programmability of SDN, and propose a new routing control plane, named RCS. It can support flexible inter-domain forwarding control, and enable network functions chaining along inter-domain paths. In RCS, network functions are abstracted and disseminated between SDN ASes. Customer networks can set up their desired routing paths for particular applications, such as multipath routing. RCS can be deployed incrementally to apply SDN to current inter-domain settings. In our primary analysis based on BGP data, the provision of customizable forwarding control at only a few ASes can lead to a large of potential path diversity.

Three for one: Pyrrolyldipyrromethenes having different functional groups were efficiently synthesized from POCl(3)-promoted condensations between 5-chloro-2-formylpyrrole or isoindole derivatives and suitable pyrrole or indole fragments through a novel nucleophilic aromatic substitution of the initially formed protonated azafulvene rings.

Formylation has been performed on pyrrole-unsubstituted dipyrromethanes 1 and boron–dipyrrin (BODIPY) dyes 4 based on a Vilsmeier–Haack reaction. It is highly regioselective and complementary and occurs exclusively at the α- and β-position, respectively, for pyrrole-unsubstituted dipyrromethanes 1 and BODIPY dyes 4. This regioselective formylation enables the syntheses of a variety of α- and β-substituted BODIPY dyes. The installation of formyl groups affects the electronic properties of the BODIPY chromophore, resulting in red- and blueshifts of the absorption and emission maxima, respectively, for the α- and β-formylatedBODIPYs 3 and 5.

A series of asymmetrical benzo-fused BODIPY dyes were synthesized from the Sonogashira coupling and nucleophilic substitution reactions on the 3-halogenated benzo-fused BODIPY, generated from readily available 3-halogeno-1-formylisoindoles in a two-step synthetic procedure. This novel BODIPY platform provides an easy path for the linking of BODIPY fluorophore to various desired functionalities as demonstrated in this work. Most of the resulting BODIPY dyes show long-wavelength absorption and fluorescence emission, with good fluorescence quantum yields and long fluorescence lifetimes.

One- and two-step reactions for the construction of the target compounds from halo(acetyl)-substituted pyrroles or isoindoles and pyrroles are given.

A weakly fluorescent nitroolefin functionalized BODIPY 1 was prepared and rapidly reacted with thiols through an unexpected conjugated addition to the azafulvene ring of BODIPY to generate highly fluorescent BODIPYs 4 and 5. This reaction was applied for the highly selective and sensitive detection of Cys in living cells.

Charger has a great impact on the performance and service life of battery and charging regime is significant for intelligent charger. Researchers usually combine two or three charging methods to get a good performance charging regime, but the effect is still less than satisfactory and cannot charge and renovate the battery at the same time. This article studies on charging regime of intelligent charger based on normal charging methods character analysis of VRLA battery and references to some charger products regimes, and gives a seven phases regime including Resonant composite pulse charging, soft start, bulk charge, absorption, battery test, recondition and float. From the result shown in experiments, this charging regime resolves the problem of failing to charge and renovate batteries simultaneously, implementing a high performance charging.