Deep Membrane Proteome Profiling Reveals Overexpression of Prostate-Specific Membrane Antigen (PSMA) in High-Risk Human Paraganglioma and Pheochromocytoma,Suggesting New Theranostic Opportunity

Pheochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumors arising from chromaffin cells of adrenal medulla or sympathetic or parasympathetic paraganglia, respectively. To identify new therapeutic targets, we performed a detailed membrane-focused proteomic analysis of five human paraganglioma (PGL) samples. Using the Pitchfork strategy, which combines specific enrichments of glycopeptides, hydrophobic transmembrane segments, and non-glycosylated extra-membrane peptides, we identified over 1800 integral membrane proteins (IMPs). We found 45 “tumor enriched” proteins, i.e., proteins identified in all five PGLs but not found in control chromaffin tissue. Among them, 18 IMPs were predicted to be localized on the cell surface, a preferred drug targeting site, including prostate-specific membrane antigen (PSMA), a well-established target for nuclear imaging and therapy of advanced prostate cancer. Using specific antibodies, we verified PSMA expression in 22 well-characterized human PPGL samples. Compared to control chromaffin tissue, PSMA was markedly overexpressed in high-risk PPGLs belonging to the established Cluster 1, which is characterized by worse clinical outcomes, pseudohypoxia, multiplicity, recurrence, and metastasis, specifically including SDHB, VHL, and EPAS1 mutations. Using immunohistochemistry, we localized PSMA expression to tumor vasculature. Our study provides the first direct evidence of PSMA overexpression in PPGLs which could translate to therapeutic and diagnostic applications of anti-PSMA radio-conjugates in high-risk PPGLs.     

Free-Standing Black Phosphorus Foils for Energy Storage and Catalysis

Few-layered black phosphorus (BP) is a two-dimensional material that has attracted intensive attention for applications in energy storage and catalysis due to its large surface area and good electrical and thermal conductivity. Herein, a comparable study of BP electrochemical exfoliation in various solutions of tetrabutylammonium salts (TBAX; X is PF₆⁻, BF₄⁻, and ClO₄⁻) in DMSO is reported. Based on morphological and structural analyses, it is shown that TBAPF₆/DMSO medium was specifically appropriate for the production of high-quality BP nanosheets with micrometer lateral size and a thickness of about 2.4 nm. TBAPF₆/DMSO-processed, few-layered BP exhibits enhanced hydrogen evolution reaction (HER) catalytic activity compared with that of samples exfoliated with the assistance of BF₄⁻ and ClO₄⁻ ions. Finally, the fabrication of flexible, free-standing BP films and their performance in an all-solid-state supercapacitor device are demonstrated.     

Alkali Metal Arenides as a Universal Synthetic Tool for Layered 2D Germanene Modification

The rediscovery of graphene in 2004 has started an enormous chase in the research of 2D materials. A new family of layered 2D materials consisting of the 14th group elements beyond carbon has already been reported. Here, a new methodology in germanene chemistry is presented using germanane (Ge₆H₆) as a stable and easily accessible starting material for effective synthesis of novel germanene derivatives. The modification procedure utilizing strong bases—alkali metal arenides—for deprotonation of germanane and its subsequent functionalization with p‐nitrobenzyl bromide is described. Functionalization of germanene is confirmed by FT‐IR, Raman, and XPS spectroscopy as well as by X‐ray diffraction analysis.     

Transitional Metal/Chalcogen Dependant Interactions of Hairpin DNA with Transition Metal Dichalcogenides,MX2

Owing to the attractive properties that transition metal dichalcogenides (TMDs) display, they have found recent application in the fabrication of biosensing devices. These devices involve the immobilization of a recognition element such as DNA onto the surface of TMDs. Therefore, it is imperative to examine the interactions between TMDs and DNA. Herein, we explore the effect of different transition metals (Mo and W) and chalcogens (S and Se) on the interactions between hairpin DNA and TMDs of both bulk and t‐BuLi exfoliated forms. We discovered that the interactions are strongly dependent on the metal/chalcogen composition in TMDs.     

Fluorinated Nanocarbons Cytotoxicity

As the research in nanotechnology progresses, there will eventually be an influx in the number of commercial products containing different types of nanomaterials. This phenomenon might damage our health and environment if the nanomaterials used are found to be toxic and they are released into the waters when the products degrade. In this study, we investigated the cytotoxicity of fluorinated nanocarbons (CXFs), a group of nanomaterials which can find applications in solid lubricants and lithium primary batteries. Our cell viability findings indicated that the toxicological effects induced by the CXF are dependent on the dose, size, shape, and fluorine content of the CXF. In addition, we verified that CXFs have insignificant interactions with the cell viability assays—methylthiazolyldiphenyl‐tetrazolium bromide (MTT) and water‐soluble tetrazolium salt (WST‐8), thus suggesting that the cytotoxicity data obtained are unlikely to be affected by CXF‐induced artifacts and the results will be reliable.     

Layered Post‐Transition‐Metal Dichalcogenides (X−M−M−X) and Their Properties

A^IIIB^VI chalcogenides are an interesting group of layered semiconductors with several attractive properties, such as tunable band gaps and the formation of solid solutions. Unlike the typically sandwiched structure of transition‐metal dichalcogenides, A^IIIB^VI layered chalcogenides with hexagonal symmetry are stacked through the X?M?M?X motif, in which M is gallium and indium, and X is sulfur, selenium, and tellurium. In view of the inadequate study of the electrochemical properties and great interest in layered materials towards energy‐related research, herein the inherent electrochemistry of GaS, GaSe, GaTe, and InSe has been studied, as well as the exploration of their potential as hydrogen evolution reaction (HER) electrocatalysts. All four materials show redox peaks during cyclic voltammetry measurements. Furthermore, insights into catalysis of the HER are provided; these indicate the conductivity and number of active sites of the materials. All of these findings have important implications on their possible applications.     

Partial Charge Transfer in the Shortest Possible Metallofullerene Peapod,La@C82⊂[11]Cycloparaphenylene

[11]Cycloparaphenylene ([11]CPP) selectively encapsulates La@C₈₂ to form the shortest possible metallofullerene–carbon nanotube (CNT) peapod, La@C₈₂?[11]CPP, in solution and in the solid state. Complexation in solution was affected by the polarity of the solvent and was 16 times stronger in the polar solvent nitrobenzene than in the nonpolar solvent 1,2‐dichlorobenzene. Electrochemical analysis revealed that the redox potentials of La@C₈₂ were negatively shifted upon complexation from free La@C₈₂. Furthermore, the shifts in the redox potentials increased with polarity of the solvent. These results are consistent with formation of a polar complex, (La@C₈₂)^δ??[11]CPP^δ+, by partial electron transfer from [11]CPP to La@C₈₂. This is the first observation of such an electronic interaction between a fullerene pea and CPP pod. Theoretical calculations also supported partial charge transfer (0.07) from [11]CPP to La@C₈₂. The structure of the complex was unambiguously determined by X‐ray crystallographic analysis, which showed the La atom inside the C₈₂ near the periphery of the [11]CPP. The dipole moment of La@C₈₂ was projected toward the CPP pea, nearly perpendicular to the CPP axis. The position of the La atom and the direction of the dipole moment in La@C₈₂?[11]CPP were significantly different from those observed in La@C₈₂?CNT, thus indicating a difference in orientation of the fullerene peas between fullerene–CPP and fullerene–CNT peapods. These results highlight the importance of pea–pea interactions in determining the orientation of the metallofullerene in metallofullerene–CNT peapods.     

Viscoelasticity of a surfactant and its drag-reducing ability

There is considerable interest in the use of viscoelastic cationic surfactant-counterion mixtures in district heating and cooling systems to reduce pressure losses. A recent field test in a secondary system near Prague showed a 30+% reduction in pumping energy requirements.We have studied a number of commercial surfactants and we report here results of rheological, drag reduction and turbulence measurements on Arquad 18–50 (octadecyl trimethyl ammonium chloride (AR 18)) with an excess of sodium salicylate (NA). The concentration studied was 1.6 mM AR 18 and 4.0 mM NA which is about one third the concentration for excellent drag reduction in this surfactant's effective temperature range 30–90°C.Viscosity, , vs. shear rate,D, first normal stress difference,N ₁, vs. shear rate, drag reduction (as pressure drop,i=P/1) vs. average velocity,U _ave, in a 39.4 mm tube for AR 18, and turbulence intensity data for three drag reducing surfactants are reported.Of particular interest are the generally low turbulence intensities in all three directions which correspond to reduced heat, mass and momentum transfer rates compared to water, and the existence of large normal stress differences at 20°C for AR 18, a temperature at which no drag reduction occurs with this surfactant, indicating that normal stress effects do not correlate directly with drag reduction.The effect of time of pumping on increasing drag reduction demonstrates that this factor overwhelms the expected increase in drag reduction as temperature is raised from 18–19°C to 40.5°C.     

世贸大厦坍塌的原因——————简要分析

对2001年9月11日纽约世贸中心大厦整体坍塌的原因作了简化的 近似分析.分析表明：如果大厦某一层大部分支柱在持续高温作用下失去 了承载能力，则整个大厦就会彻底坍塌.尽管采用了一些对承载能力有利 的简化假设，但仍发现其结构抗力比实际所需的承载能力低一个数量级.